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 #include <net/inet_dscp.h> 57 58 MODULE_AUTHOR("Ville Nuorvala"); 59 MODULE_DESCRIPTION("IPv6 tunneling device"); 60 MODULE_LICENSE("GPL"); 61 MODULE_ALIAS_RTNL_LINK("ip6tnl"); 62 MODULE_ALIAS_NETDEV("ip6tnl0"); 63 64 #define IP6_TUNNEL_HASH_SIZE_SHIFT 5 65 #define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT) 66 67 static bool log_ecn_error = true; 68 module_param(log_ecn_error, bool, 0644); 69 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 70 71 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) 72 { 73 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); 74 75 return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT); 76 } 77 78 static int ip6_tnl_dev_init(struct net_device *dev); 79 static void ip6_tnl_dev_setup(struct net_device *dev); 80 static struct rtnl_link_ops ip6_link_ops __read_mostly; 81 82 static unsigned int ip6_tnl_net_id __read_mostly; 83 struct ip6_tnl_net { 84 /* the IPv6 tunnel fallback device */ 85 struct net_device *fb_tnl_dev; 86 /* lists for storing tunnels in use */ 87 struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE]; 88 struct ip6_tnl __rcu *tnls_wc[1]; 89 struct ip6_tnl __rcu **tnls[2]; 90 struct ip6_tnl __rcu *collect_md_tun; 91 }; 92 93 static inline int ip6_tnl_mpls_supported(void) 94 { 95 return IS_ENABLED(CONFIG_MPLS); 96 } 97 98 #define for_each_ip6_tunnel_rcu(start) \ 99 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 100 101 /** 102 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 103 * @net: network namespace 104 * @link: ifindex of underlying interface 105 * @remote: the address of the tunnel exit-point 106 * @local: the address of the tunnel entry-point 107 * 108 * Return: 109 * tunnel matching given end-points if found, 110 * else fallback tunnel if its device is up, 111 * else %NULL 112 **/ 113 114 static struct ip6_tnl * 115 ip6_tnl_lookup(struct net *net, int link, 116 const struct in6_addr *remote, const struct in6_addr *local) 117 { 118 unsigned int hash = HASH(remote, local); 119 struct ip6_tnl *t, *cand = NULL; 120 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 121 struct in6_addr any; 122 123 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 124 if (!ipv6_addr_equal(local, &t->parms.laddr) || 125 !ipv6_addr_equal(remote, &t->parms.raddr) || 126 !(t->dev->flags & IFF_UP)) 127 continue; 128 129 if (link == t->parms.link) 130 return t; 131 else 132 cand = t; 133 } 134 135 memset(&any, 0, sizeof(any)); 136 hash = HASH(&any, local); 137 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 138 if (!ipv6_addr_equal(local, &t->parms.laddr) || 139 !ipv6_addr_any(&t->parms.raddr) || 140 !(t->dev->flags & IFF_UP)) 141 continue; 142 143 if (link == t->parms.link) 144 return t; 145 else if (!cand) 146 cand = t; 147 } 148 149 hash = HASH(remote, &any); 150 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 151 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 152 !ipv6_addr_any(&t->parms.laddr) || 153 !(t->dev->flags & IFF_UP)) 154 continue; 155 156 if (link == t->parms.link) 157 return t; 158 else if (!cand) 159 cand = t; 160 } 161 162 if (cand) 163 return cand; 164 165 t = rcu_dereference(ip6n->collect_md_tun); 166 if (t && t->dev->flags & IFF_UP) 167 return t; 168 169 t = rcu_dereference(ip6n->tnls_wc[0]); 170 if (t && (t->dev->flags & IFF_UP)) 171 return t; 172 173 return NULL; 174 } 175 176 /** 177 * ip6_tnl_bucket - get head of list matching given tunnel parameters 178 * @ip6n: the private data for ip6_vti in the netns 179 * @p: parameters containing tunnel end-points 180 * 181 * Description: 182 * ip6_tnl_bucket() returns the head of the list matching the 183 * &struct in6_addr entries laddr and raddr in @p. 184 * 185 * Return: head of IPv6 tunnel list 186 **/ 187 188 static struct ip6_tnl __rcu ** 189 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p) 190 { 191 const struct in6_addr *remote = &p->raddr; 192 const struct in6_addr *local = &p->laddr; 193 unsigned int h = 0; 194 int prio = 0; 195 196 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 197 prio = 1; 198 h = HASH(remote, local); 199 } 200 return &ip6n->tnls[prio][h]; 201 } 202 203 /** 204 * ip6_tnl_link - add tunnel to hash table 205 * @ip6n: the private data for ip6_vti in the netns 206 * @t: tunnel to be added 207 **/ 208 209 static void 210 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 211 { 212 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); 213 214 if (t->parms.collect_md) 215 rcu_assign_pointer(ip6n->collect_md_tun, t); 216 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 217 rcu_assign_pointer(*tp, t); 218 } 219 220 /** 221 * ip6_tnl_unlink - remove tunnel from hash table 222 * @ip6n: the private data for ip6_vti in the netns 223 * @t: tunnel to be removed 224 **/ 225 226 static void 227 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 228 { 229 struct ip6_tnl __rcu **tp; 230 struct ip6_tnl *iter; 231 232 if (t->parms.collect_md) 233 rcu_assign_pointer(ip6n->collect_md_tun, NULL); 234 235 for (tp = ip6_tnl_bucket(ip6n, &t->parms); 236 (iter = rtnl_dereference(*tp)) != NULL; 237 tp = &iter->next) { 238 if (t == iter) { 239 rcu_assign_pointer(*tp, t->next); 240 break; 241 } 242 } 243 } 244 245 static void ip6_dev_free(struct net_device *dev) 246 { 247 struct ip6_tnl *t = netdev_priv(dev); 248 249 gro_cells_destroy(&t->gro_cells); 250 dst_cache_destroy(&t->dst_cache); 251 } 252 253 static int ip6_tnl_create2(struct net_device *dev) 254 { 255 struct ip6_tnl *t = netdev_priv(dev); 256 struct net *net = dev_net(dev); 257 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 258 int err; 259 260 dev->rtnl_link_ops = &ip6_link_ops; 261 err = register_netdevice(dev); 262 if (err < 0) 263 goto out; 264 265 strcpy(t->parms.name, dev->name); 266 267 ip6_tnl_link(ip6n, t); 268 return 0; 269 270 out: 271 return err; 272 } 273 274 /** 275 * ip6_tnl_create - create a new tunnel 276 * @net: network namespace 277 * @p: tunnel parameters 278 * 279 * Description: 280 * Create tunnel matching given parameters. 281 * 282 * Return: 283 * created tunnel or error pointer 284 **/ 285 286 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 287 { 288 struct net_device *dev; 289 struct ip6_tnl *t; 290 char name[IFNAMSIZ]; 291 int err = -E2BIG; 292 293 if (p->name[0]) { 294 if (!dev_valid_name(p->name)) 295 goto failed; 296 strscpy(name, p->name, IFNAMSIZ); 297 } else { 298 sprintf(name, "ip6tnl%%d"); 299 } 300 err = -ENOMEM; 301 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 302 ip6_tnl_dev_setup); 303 if (!dev) 304 goto failed; 305 306 dev_net_set(dev, net); 307 308 t = netdev_priv(dev); 309 t->parms = *p; 310 t->net = dev_net(dev); 311 err = ip6_tnl_create2(dev); 312 if (err < 0) 313 goto failed_free; 314 315 return t; 316 317 failed_free: 318 free_netdev(dev); 319 failed: 320 return ERR_PTR(err); 321 } 322 323 /** 324 * ip6_tnl_locate - find or create tunnel matching given parameters 325 * @net: network namespace 326 * @p: tunnel parameters 327 * @create: != 0 if allowed to create new tunnel if no match found 328 * 329 * Description: 330 * ip6_tnl_locate() first tries to locate an existing tunnel 331 * based on @parms. If this is unsuccessful, but @create is set a new 332 * tunnel device is created and registered for use. 333 * 334 * Return: 335 * matching tunnel or error pointer 336 **/ 337 338 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 339 struct __ip6_tnl_parm *p, int create) 340 { 341 const struct in6_addr *remote = &p->raddr; 342 const struct in6_addr *local = &p->laddr; 343 struct ip6_tnl __rcu **tp; 344 struct ip6_tnl *t; 345 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 346 347 for (tp = ip6_tnl_bucket(ip6n, p); 348 (t = rtnl_dereference(*tp)) != NULL; 349 tp = &t->next) { 350 if (ipv6_addr_equal(local, &t->parms.laddr) && 351 ipv6_addr_equal(remote, &t->parms.raddr) && 352 p->link == t->parms.link) { 353 if (create) 354 return ERR_PTR(-EEXIST); 355 356 return t; 357 } 358 } 359 if (!create) 360 return ERR_PTR(-ENODEV); 361 return ip6_tnl_create(net, p); 362 } 363 364 /** 365 * ip6_tnl_dev_uninit - tunnel device uninitializer 366 * @dev: the device to be destroyed 367 * 368 * Description: 369 * ip6_tnl_dev_uninit() removes tunnel from its list 370 **/ 371 372 static void 373 ip6_tnl_dev_uninit(struct net_device *dev) 374 { 375 struct ip6_tnl *t = netdev_priv(dev); 376 struct net *net = t->net; 377 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 378 379 if (dev == ip6n->fb_tnl_dev) 380 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 381 else 382 ip6_tnl_unlink(ip6n, t); 383 dst_cache_reset(&t->dst_cache); 384 netdev_put(dev, &t->dev_tracker); 385 } 386 387 /** 388 * ip6_tnl_parse_tlv_enc_lim - handle encapsulation limit option 389 * @skb: received socket buffer 390 * @raw: the ICMPv6 error message data 391 * 392 * Return: 393 * 0 if none was found, 394 * else index to encapsulation limit 395 **/ 396 397 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) 398 { 399 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw; 400 unsigned int nhoff = raw - skb->data; 401 unsigned int off = nhoff + sizeof(*ipv6h); 402 u8 nexthdr = ipv6h->nexthdr; 403 404 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 405 struct ipv6_opt_hdr *hdr; 406 u16 optlen; 407 408 if (!pskb_may_pull(skb, off + sizeof(*hdr))) 409 break; 410 411 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 412 if (nexthdr == NEXTHDR_FRAGMENT) { 413 optlen = 8; 414 } else if (nexthdr == NEXTHDR_AUTH) { 415 optlen = ipv6_authlen(hdr); 416 } else { 417 optlen = ipv6_optlen(hdr); 418 } 419 420 if (!pskb_may_pull(skb, off + optlen)) 421 break; 422 423 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 424 if (nexthdr == NEXTHDR_FRAGMENT) { 425 struct frag_hdr *frag_hdr = (struct frag_hdr *)hdr; 426 427 if (frag_hdr->frag_off) 428 break; 429 } 430 if (nexthdr == NEXTHDR_DEST) { 431 u16 i = 2; 432 433 while (1) { 434 struct ipv6_tlv_tnl_enc_lim *tel; 435 436 /* No more room for encapsulation limit */ 437 if (i + sizeof(*tel) > optlen) 438 break; 439 440 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i); 441 /* return index of option if found and valid */ 442 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 443 tel->length == 1) 444 return i + off - nhoff; 445 /* else jump to next option */ 446 if (tel->type) 447 i += tel->length + 2; 448 else 449 i++; 450 } 451 } 452 nexthdr = hdr->nexthdr; 453 off += optlen; 454 } 455 return 0; 456 } 457 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); 458 459 /* ip6_tnl_err() should handle errors in the tunnel according to the 460 * specifications in RFC 2473. 461 */ 462 static int 463 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 464 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 465 { 466 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 467 struct net *net = dev_net(skb->dev); 468 u8 rel_type = ICMPV6_DEST_UNREACH; 469 u8 rel_code = ICMPV6_ADDR_UNREACH; 470 __u32 rel_info = 0; 471 struct ip6_tnl *t; 472 int err = -ENOENT; 473 int rel_msg = 0; 474 u8 tproto; 475 __u16 len; 476 477 /* If the packet doesn't contain the original IPv6 header we are 478 in trouble since we might need the source address for further 479 processing of the error. */ 480 481 rcu_read_lock(); 482 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr); 483 if (!t) 484 goto out; 485 486 tproto = READ_ONCE(t->parms.proto); 487 if (tproto != ipproto && tproto != 0) 488 goto out; 489 490 err = 0; 491 492 switch (*type) { 493 case ICMPV6_DEST_UNREACH: 494 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 495 t->parms.name); 496 rel_msg = 1; 497 break; 498 case ICMPV6_TIME_EXCEED: 499 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 500 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 501 t->parms.name); 502 rel_msg = 1; 503 } 504 break; 505 case ICMPV6_PARAMPROB: { 506 struct ipv6_tlv_tnl_enc_lim *tel; 507 __u32 teli; 508 509 teli = 0; 510 if ((*code) == ICMPV6_HDR_FIELD) 511 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 512 513 if (teli && teli == *info - 2) { 514 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 515 if (tel->encap_limit == 0) { 516 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 517 t->parms.name); 518 rel_msg = 1; 519 } 520 } else { 521 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 522 t->parms.name); 523 } 524 break; 525 } 526 case ICMPV6_PKT_TOOBIG: { 527 __u32 mtu; 528 529 ip6_update_pmtu(skb, net, htonl(*info), 0, 0, 530 sock_net_uid(net, NULL)); 531 mtu = *info - offset; 532 if (mtu < IPV6_MIN_MTU) 533 mtu = IPV6_MIN_MTU; 534 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len); 535 if (len > mtu) { 536 rel_type = ICMPV6_PKT_TOOBIG; 537 rel_code = 0; 538 rel_info = mtu; 539 rel_msg = 1; 540 } 541 break; 542 } 543 case NDISC_REDIRECT: 544 ip6_redirect(skb, net, skb->dev->ifindex, 0, 545 sock_net_uid(net, NULL)); 546 break; 547 } 548 549 *type = rel_type; 550 *code = rel_code; 551 *info = rel_info; 552 *msg = rel_msg; 553 554 out: 555 rcu_read_unlock(); 556 return err; 557 } 558 559 static int 560 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 561 u8 type, u8 code, int offset, __be32 info) 562 { 563 __u32 rel_info = ntohl(info); 564 const struct iphdr *eiph; 565 struct sk_buff *skb2; 566 int err, rel_msg = 0; 567 u8 rel_type = type; 568 u8 rel_code = code; 569 struct rtable *rt; 570 struct flowi4 fl4; 571 572 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 573 &rel_msg, &rel_info, offset); 574 if (err < 0) 575 return err; 576 577 if (rel_msg == 0) 578 return 0; 579 580 switch (rel_type) { 581 case ICMPV6_DEST_UNREACH: 582 if (rel_code != ICMPV6_ADDR_UNREACH) 583 return 0; 584 rel_type = ICMP_DEST_UNREACH; 585 rel_code = ICMP_HOST_UNREACH; 586 break; 587 case ICMPV6_PKT_TOOBIG: 588 if (rel_code != 0) 589 return 0; 590 rel_type = ICMP_DEST_UNREACH; 591 rel_code = ICMP_FRAG_NEEDED; 592 break; 593 default: 594 return 0; 595 } 596 597 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 598 return 0; 599 600 skb2 = skb_clone(skb, GFP_ATOMIC); 601 if (!skb2) 602 return 0; 603 604 skb_dst_drop(skb2); 605 606 skb_pull(skb2, offset); 607 skb_reset_network_header(skb2); 608 eiph = ip_hdr(skb2); 609 610 /* Try to guess incoming interface */ 611 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr, 612 0, 0, 0, IPPROTO_IPIP, 613 eiph->tos & INET_DSCP_MASK, 0); 614 if (IS_ERR(rt)) 615 goto out; 616 617 skb2->dev = rt->dst.dev; 618 ip_rt_put(rt); 619 620 /* route "incoming" packet */ 621 if (rt->rt_flags & RTCF_LOCAL) { 622 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 623 eiph->daddr, eiph->saddr, 0, 0, 624 IPPROTO_IPIP, 625 eiph->tos & INET_DSCP_MASK, 0); 626 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) { 627 if (!IS_ERR(rt)) 628 ip_rt_put(rt); 629 goto out; 630 } 631 skb_dst_set(skb2, &rt->dst); 632 } else { 633 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 634 skb2->dev) || 635 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6) 636 goto out; 637 } 638 639 /* change mtu on this route */ 640 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 641 if (rel_info > dst_mtu(skb_dst(skb2))) 642 goto out; 643 644 skb_dst_update_pmtu_no_confirm(skb2, rel_info); 645 } 646 647 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 648 649 out: 650 kfree_skb(skb2); 651 return 0; 652 } 653 654 static int 655 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 656 u8 type, u8 code, int offset, __be32 info) 657 { 658 __u32 rel_info = ntohl(info); 659 int err, rel_msg = 0; 660 u8 rel_type = type; 661 u8 rel_code = code; 662 663 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 664 &rel_msg, &rel_info, offset); 665 if (err < 0) 666 return err; 667 668 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 669 struct rt6_info *rt; 670 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 671 672 if (!skb2) 673 return 0; 674 675 skb_dst_drop(skb2); 676 skb_pull(skb2, offset); 677 skb_reset_network_header(skb2); 678 679 /* Try to guess incoming interface */ 680 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 681 NULL, 0, skb2, 0); 682 683 if (rt && rt->dst.dev) 684 skb2->dev = rt->dst.dev; 685 686 icmpv6_send(skb2, rel_type, rel_code, rel_info); 687 688 ip6_rt_put(rt); 689 690 kfree_skb(skb2); 691 } 692 693 return 0; 694 } 695 696 static int 697 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 698 u8 type, u8 code, int offset, __be32 info) 699 { 700 __u32 rel_info = ntohl(info); 701 int err, rel_msg = 0; 702 u8 rel_type = type; 703 u8 rel_code = code; 704 705 err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code, 706 &rel_msg, &rel_info, offset); 707 return err; 708 } 709 710 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 711 const struct ipv6hdr *ipv6h, 712 struct sk_buff *skb) 713 { 714 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 715 716 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 717 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 718 719 return IP6_ECN_decapsulate(ipv6h, skb); 720 } 721 722 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 723 const struct ipv6hdr *ipv6h, 724 struct sk_buff *skb) 725 { 726 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 727 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 728 729 return IP6_ECN_decapsulate(ipv6h, skb); 730 } 731 732 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 733 const struct ipv6hdr *ipv6h, 734 struct sk_buff *skb) 735 { 736 /* ECN is not supported in AF_MPLS */ 737 return 0; 738 } 739 740 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 741 const struct in6_addr *laddr, 742 const struct in6_addr *raddr) 743 { 744 struct __ip6_tnl_parm *p = &t->parms; 745 int ltype = ipv6_addr_type(laddr); 746 int rtype = ipv6_addr_type(raddr); 747 __u32 flags = 0; 748 749 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 750 flags = IP6_TNL_F_CAP_PER_PACKET; 751 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 752 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 753 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 754 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 755 if (ltype&IPV6_ADDR_UNICAST) 756 flags |= IP6_TNL_F_CAP_XMIT; 757 if (rtype&IPV6_ADDR_UNICAST) 758 flags |= IP6_TNL_F_CAP_RCV; 759 } 760 return flags; 761 } 762 EXPORT_SYMBOL(ip6_tnl_get_cap); 763 764 /* called with rcu_read_lock() */ 765 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 766 const struct in6_addr *laddr, 767 const struct in6_addr *raddr) 768 { 769 struct __ip6_tnl_parm *p = &t->parms; 770 int ret = 0; 771 struct net *net = t->net; 772 773 if ((p->flags & IP6_TNL_F_CAP_RCV) || 774 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 775 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 776 struct net_device *ldev = NULL; 777 778 if (p->link) 779 ldev = dev_get_by_index_rcu(net, p->link); 780 781 if ((ipv6_addr_is_multicast(laddr) || 782 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false, 783 0, IFA_F_TENTATIVE))) && 784 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) || 785 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true, 786 0, IFA_F_TENTATIVE)))) 787 ret = 1; 788 } 789 return ret; 790 } 791 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 792 793 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb, 794 const struct tnl_ptk_info *tpi, 795 struct metadata_dst *tun_dst, 796 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 797 const struct ipv6hdr *ipv6h, 798 struct sk_buff *skb), 799 bool log_ecn_err) 800 { 801 const struct ipv6hdr *ipv6h; 802 int nh, err; 803 804 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.i_flags) != 805 test_bit(IP_TUNNEL_CSUM_BIT, tpi->flags)) { 806 DEV_STATS_INC(tunnel->dev, rx_crc_errors); 807 DEV_STATS_INC(tunnel->dev, rx_errors); 808 goto drop; 809 } 810 811 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.i_flags)) { 812 if (!test_bit(IP_TUNNEL_SEQ_BIT, tpi->flags) || 813 (tunnel->i_seqno && 814 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 815 DEV_STATS_INC(tunnel->dev, rx_fifo_errors); 816 DEV_STATS_INC(tunnel->dev, rx_errors); 817 goto drop; 818 } 819 tunnel->i_seqno = ntohl(tpi->seq) + 1; 820 } 821 822 skb->protocol = tpi->proto; 823 824 /* Warning: All skb pointers will be invalidated! */ 825 if (tunnel->dev->type == ARPHRD_ETHER) { 826 if (!pskb_may_pull(skb, ETH_HLEN)) { 827 DEV_STATS_INC(tunnel->dev, rx_length_errors); 828 DEV_STATS_INC(tunnel->dev, rx_errors); 829 goto drop; 830 } 831 832 skb->protocol = eth_type_trans(skb, tunnel->dev); 833 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 834 } else { 835 skb->dev = tunnel->dev; 836 skb_reset_mac_header(skb); 837 } 838 839 /* Save offset of outer header relative to skb->head, 840 * because we are going to reset the network header to the inner header 841 * and might change skb->head. 842 */ 843 nh = skb_network_header(skb) - skb->head; 844 845 skb_reset_network_header(skb); 846 847 if (!pskb_inet_may_pull(skb)) { 848 DEV_STATS_INC(tunnel->dev, rx_length_errors); 849 DEV_STATS_INC(tunnel->dev, rx_errors); 850 goto drop; 851 } 852 853 /* Get the outer header. */ 854 ipv6h = (struct ipv6hdr *)(skb->head + nh); 855 856 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 857 858 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 859 860 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 861 if (unlikely(err)) { 862 if (log_ecn_err) 863 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 864 &ipv6h->saddr, 865 ipv6_get_dsfield(ipv6h)); 866 if (err > 1) { 867 DEV_STATS_INC(tunnel->dev, rx_frame_errors); 868 DEV_STATS_INC(tunnel->dev, rx_errors); 869 goto drop; 870 } 871 } 872 873 dev_sw_netstats_rx_add(tunnel->dev, skb->len); 874 875 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 876 877 if (tun_dst) 878 skb_dst_set(skb, (struct dst_entry *)tun_dst); 879 880 gro_cells_receive(&tunnel->gro_cells, skb); 881 return 0; 882 883 drop: 884 if (tun_dst) 885 dst_release((struct dst_entry *)tun_dst); 886 kfree_skb(skb); 887 return 0; 888 } 889 890 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 891 const struct tnl_ptk_info *tpi, 892 struct metadata_dst *tun_dst, 893 bool log_ecn_err) 894 { 895 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 896 const struct ipv6hdr *ipv6h, 897 struct sk_buff *skb); 898 899 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate; 900 if (tpi->proto == htons(ETH_P_IP)) 901 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate; 902 903 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 904 log_ecn_err); 905 } 906 EXPORT_SYMBOL(ip6_tnl_rcv); 907 908 static const struct tnl_ptk_info tpi_v6 = { 909 /* no tunnel info required for ipxip6. */ 910 .proto = htons(ETH_P_IPV6), 911 }; 912 913 static const struct tnl_ptk_info tpi_v4 = { 914 /* no tunnel info required for ipxip6. */ 915 .proto = htons(ETH_P_IP), 916 }; 917 918 static const struct tnl_ptk_info tpi_mpls = { 919 /* no tunnel info required for mplsip6. */ 920 .proto = htons(ETH_P_MPLS_UC), 921 }; 922 923 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 924 const struct tnl_ptk_info *tpi, 925 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 926 const struct ipv6hdr *ipv6h, 927 struct sk_buff *skb)) 928 { 929 struct ip6_tnl *t; 930 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 931 struct metadata_dst *tun_dst = NULL; 932 int ret = -1; 933 934 rcu_read_lock(); 935 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 936 937 if (t) { 938 u8 tproto = READ_ONCE(t->parms.proto); 939 940 if (tproto != ipproto && tproto != 0) 941 goto drop; 942 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 943 goto drop; 944 ipv6h = ipv6_hdr(skb); 945 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 946 goto drop; 947 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 948 goto drop; 949 if (t->parms.collect_md) { 950 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 951 952 tun_dst = ipv6_tun_rx_dst(skb, flags, 0, 0); 953 if (!tun_dst) 954 goto drop; 955 } 956 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 957 log_ecn_error); 958 } 959 960 rcu_read_unlock(); 961 962 return ret; 963 964 drop: 965 rcu_read_unlock(); 966 kfree_skb(skb); 967 return 0; 968 } 969 970 static int ip4ip6_rcv(struct sk_buff *skb) 971 { 972 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 973 ip4ip6_dscp_ecn_decapsulate); 974 } 975 976 static int ip6ip6_rcv(struct sk_buff *skb) 977 { 978 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 979 ip6ip6_dscp_ecn_decapsulate); 980 } 981 982 static int mplsip6_rcv(struct sk_buff *skb) 983 { 984 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls, 985 mplsip6_dscp_ecn_decapsulate); 986 } 987 988 struct ipv6_tel_txoption { 989 struct ipv6_txoptions ops; 990 __u8 dst_opt[8]; 991 }; 992 993 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 994 { 995 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 996 997 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 998 opt->dst_opt[3] = 1; 999 opt->dst_opt[4] = encap_limit; 1000 opt->dst_opt[5] = IPV6_TLV_PADN; 1001 opt->dst_opt[6] = 1; 1002 1003 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 1004 opt->ops.opt_nflen = 8; 1005 } 1006 1007 /** 1008 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 1009 * @t: the outgoing tunnel device 1010 * @hdr: IPv6 header from the incoming packet 1011 * 1012 * Description: 1013 * Avoid trivial tunneling loop by checking that tunnel exit-point 1014 * doesn't match source of incoming packet. 1015 * 1016 * Return: 1017 * 1 if conflict, 1018 * 0 else 1019 **/ 1020 1021 static inline bool 1022 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 1023 { 1024 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 1025 } 1026 1027 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1028 const struct in6_addr *laddr, 1029 const struct in6_addr *raddr) 1030 { 1031 struct __ip6_tnl_parm *p = &t->parms; 1032 int ret = 0; 1033 struct net *net = t->net; 1034 1035 if (t->parms.collect_md) 1036 return 1; 1037 1038 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1039 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1040 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1041 struct net_device *ldev = NULL; 1042 1043 rcu_read_lock(); 1044 if (p->link) 1045 ldev = dev_get_by_index_rcu(net, p->link); 1046 1047 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1048 0, IFA_F_TENTATIVE))) 1049 pr_warn_ratelimited("%s xmit: Local address not yet configured!\n", 1050 p->name); 1051 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1052 !ipv6_addr_is_multicast(raddr) && 1053 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1054 true, 0, IFA_F_TENTATIVE))) 1055 pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n", 1056 p->name); 1057 else 1058 ret = 1; 1059 rcu_read_unlock(); 1060 } 1061 return ret; 1062 } 1063 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1064 1065 /** 1066 * ip6_tnl_xmit - encapsulate packet and send 1067 * @skb: the outgoing socket buffer 1068 * @dev: the outgoing tunnel device 1069 * @dsfield: dscp code for outer header 1070 * @fl6: flow of tunneled packet 1071 * @encap_limit: encapsulation limit 1072 * @pmtu: Path MTU is stored if packet is too big 1073 * @proto: next header value 1074 * 1075 * Description: 1076 * Build new header and do some sanity checks on the packet before sending 1077 * it. 1078 * 1079 * Return: 1080 * 0 on success 1081 * -1 fail 1082 * %-EMSGSIZE message too big. return mtu in this case. 1083 **/ 1084 1085 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1086 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1087 __u8 proto) 1088 { 1089 struct ip6_tnl *t = netdev_priv(dev); 1090 struct net *net = t->net; 1091 struct ipv6hdr *ipv6h; 1092 struct ipv6_tel_txoption opt; 1093 struct dst_entry *dst = NULL, *ndst = NULL; 1094 struct net_device *tdev; 1095 int mtu; 1096 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1097 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1098 unsigned int max_headroom = psh_hlen; 1099 __be16 payload_protocol; 1100 bool use_cache = false; 1101 u8 hop_limit; 1102 int err = -1; 1103 1104 payload_protocol = skb_protocol(skb, true); 1105 1106 if (t->parms.collect_md) { 1107 hop_limit = skb_tunnel_info(skb)->key.ttl; 1108 goto route_lookup; 1109 } else { 1110 hop_limit = t->parms.hop_limit; 1111 } 1112 1113 /* NBMA tunnel */ 1114 if (ipv6_addr_any(&t->parms.raddr)) { 1115 if (payload_protocol == htons(ETH_P_IPV6)) { 1116 struct in6_addr *addr6; 1117 struct neighbour *neigh; 1118 int addr_type; 1119 1120 if (!skb_dst(skb)) 1121 goto tx_err_link_failure; 1122 1123 neigh = dst_neigh_lookup(skb_dst(skb), 1124 &ipv6_hdr(skb)->daddr); 1125 if (!neigh) 1126 goto tx_err_link_failure; 1127 1128 addr6 = (struct in6_addr *)&neigh->primary_key; 1129 addr_type = ipv6_addr_type(addr6); 1130 1131 if (addr_type == IPV6_ADDR_ANY) 1132 addr6 = &ipv6_hdr(skb)->daddr; 1133 1134 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1135 neigh_release(neigh); 1136 } else if (payload_protocol == htons(ETH_P_IP)) { 1137 const struct rtable *rt = skb_rtable(skb); 1138 1139 if (!rt) 1140 goto tx_err_link_failure; 1141 1142 if (rt->rt_gw_family == AF_INET6) 1143 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr)); 1144 } 1145 } else if (t->parms.proto != 0 && !(t->parms.flags & 1146 (IP6_TNL_F_USE_ORIG_TCLASS | 1147 IP6_TNL_F_USE_ORIG_FWMARK))) { 1148 /* enable the cache only if neither the outer protocol nor the 1149 * routing decision depends on the current inner header value 1150 */ 1151 use_cache = true; 1152 } 1153 1154 if (use_cache) 1155 dst = dst_cache_get(&t->dst_cache); 1156 1157 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1158 goto tx_err_link_failure; 1159 1160 if (!dst) { 1161 route_lookup: 1162 /* add dsfield to flowlabel for route lookup */ 1163 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1164 1165 dst = ip6_route_output(net, NULL, fl6); 1166 1167 if (dst->error) 1168 goto tx_err_link_failure; 1169 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1170 if (IS_ERR(dst)) { 1171 err = PTR_ERR(dst); 1172 dst = NULL; 1173 goto tx_err_link_failure; 1174 } 1175 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1176 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1177 &fl6->daddr, 0, &fl6->saddr)) 1178 goto tx_err_link_failure; 1179 ndst = dst; 1180 } 1181 1182 tdev = dst->dev; 1183 1184 if (tdev == dev) { 1185 DEV_STATS_INC(dev, collisions); 1186 net_warn_ratelimited("%s: Local routing loop detected!\n", 1187 t->parms.name); 1188 goto tx_err_dst_release; 1189 } 1190 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1191 if (encap_limit >= 0) { 1192 max_headroom += 8; 1193 mtu -= 8; 1194 } 1195 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1196 IPV6_MIN_MTU : IPV4_MIN_MTU); 1197 1198 skb_dst_update_pmtu_no_confirm(skb, mtu); 1199 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1200 *pmtu = mtu; 1201 err = -EMSGSIZE; 1202 goto tx_err_dst_release; 1203 } 1204 1205 if (t->err_count > 0) { 1206 if (time_before(jiffies, 1207 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1208 t->err_count--; 1209 1210 dst_link_failure(skb); 1211 } else { 1212 t->err_count = 0; 1213 } 1214 } 1215 1216 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1217 1218 /* 1219 * Okay, now see if we can stuff it in the buffer as-is. 1220 */ 1221 max_headroom += LL_RESERVED_SPACE(tdev); 1222 1223 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1224 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1225 struct sk_buff *new_skb; 1226 1227 new_skb = skb_realloc_headroom(skb, max_headroom); 1228 if (!new_skb) 1229 goto tx_err_dst_release; 1230 1231 if (skb->sk) 1232 skb_set_owner_w(new_skb, skb->sk); 1233 consume_skb(skb); 1234 skb = new_skb; 1235 } 1236 1237 if (t->parms.collect_md) { 1238 if (t->encap.type != TUNNEL_ENCAP_NONE) 1239 goto tx_err_dst_release; 1240 } else { 1241 if (use_cache && ndst) 1242 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1243 } 1244 skb_dst_set(skb, dst); 1245 1246 if (hop_limit == 0) { 1247 if (payload_protocol == htons(ETH_P_IP)) 1248 hop_limit = ip_hdr(skb)->ttl; 1249 else if (payload_protocol == htons(ETH_P_IPV6)) 1250 hop_limit = ipv6_hdr(skb)->hop_limit; 1251 else 1252 hop_limit = ip6_dst_hoplimit(dst); 1253 } 1254 1255 /* Calculate max headroom for all the headers and adjust 1256 * needed_headroom if necessary. 1257 */ 1258 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1259 + dst->header_len + t->hlen; 1260 if (max_headroom > READ_ONCE(dev->needed_headroom)) 1261 WRITE_ONCE(dev->needed_headroom, max_headroom); 1262 1263 err = ip6_tnl_encap(skb, t, &proto, fl6); 1264 if (err) 1265 return err; 1266 1267 if (encap_limit >= 0) { 1268 init_tel_txopt(&opt, encap_limit); 1269 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1270 } 1271 1272 skb_push(skb, sizeof(struct ipv6hdr)); 1273 skb_reset_network_header(skb); 1274 ipv6h = ipv6_hdr(skb); 1275 ip6_flow_hdr(ipv6h, dsfield, 1276 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1277 ipv6h->hop_limit = hop_limit; 1278 ipv6h->nexthdr = proto; 1279 ipv6h->saddr = fl6->saddr; 1280 ipv6h->daddr = fl6->daddr; 1281 ip6tunnel_xmit(NULL, skb, dev); 1282 return 0; 1283 tx_err_link_failure: 1284 DEV_STATS_INC(dev, tx_carrier_errors); 1285 dst_link_failure(skb); 1286 tx_err_dst_release: 1287 dst_release(dst); 1288 return err; 1289 } 1290 EXPORT_SYMBOL(ip6_tnl_xmit); 1291 1292 static inline int 1293 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, 1294 u8 protocol) 1295 { 1296 struct ip6_tnl *t = netdev_priv(dev); 1297 struct ipv6hdr *ipv6h; 1298 const struct iphdr *iph; 1299 int encap_limit = -1; 1300 __u16 offset; 1301 struct flowi6 fl6; 1302 __u8 dsfield, orig_dsfield; 1303 __u32 mtu; 1304 u8 tproto; 1305 int err; 1306 1307 tproto = READ_ONCE(t->parms.proto); 1308 if (tproto != protocol && tproto != 0) 1309 return -1; 1310 1311 if (t->parms.collect_md) { 1312 struct ip_tunnel_info *tun_info; 1313 const struct ip_tunnel_key *key; 1314 1315 tun_info = skb_tunnel_info(skb); 1316 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1317 ip_tunnel_info_af(tun_info) != AF_INET6)) 1318 return -1; 1319 key = &tun_info->key; 1320 memset(&fl6, 0, sizeof(fl6)); 1321 fl6.flowi6_proto = protocol; 1322 fl6.saddr = key->u.ipv6.src; 1323 fl6.daddr = key->u.ipv6.dst; 1324 fl6.flowlabel = key->label; 1325 dsfield = key->tos; 1326 switch (protocol) { 1327 case IPPROTO_IPIP: 1328 iph = ip_hdr(skb); 1329 orig_dsfield = ipv4_get_dsfield(iph); 1330 break; 1331 case IPPROTO_IPV6: 1332 ipv6h = ipv6_hdr(skb); 1333 orig_dsfield = ipv6_get_dsfield(ipv6h); 1334 break; 1335 default: 1336 orig_dsfield = dsfield; 1337 break; 1338 } 1339 } else { 1340 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1341 encap_limit = t->parms.encap_limit; 1342 if (protocol == IPPROTO_IPV6) { 1343 offset = ip6_tnl_parse_tlv_enc_lim(skb, 1344 skb_network_header(skb)); 1345 /* ip6_tnl_parse_tlv_enc_lim() might have 1346 * reallocated skb->head 1347 */ 1348 if (offset > 0) { 1349 struct ipv6_tlv_tnl_enc_lim *tel; 1350 1351 tel = (void *)&skb_network_header(skb)[offset]; 1352 if (tel->encap_limit == 0) { 1353 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB, 1354 ICMPV6_HDR_FIELD, offset + 2); 1355 return -1; 1356 } 1357 encap_limit = tel->encap_limit - 1; 1358 } 1359 } 1360 1361 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1362 fl6.flowi6_proto = protocol; 1363 1364 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1365 fl6.flowi6_mark = skb->mark; 1366 else 1367 fl6.flowi6_mark = t->parms.fwmark; 1368 switch (protocol) { 1369 case IPPROTO_IPIP: 1370 iph = ip_hdr(skb); 1371 orig_dsfield = ipv4_get_dsfield(iph); 1372 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1373 dsfield = orig_dsfield; 1374 else 1375 dsfield = ip6_tclass(t->parms.flowinfo); 1376 break; 1377 case IPPROTO_IPV6: 1378 ipv6h = ipv6_hdr(skb); 1379 orig_dsfield = ipv6_get_dsfield(ipv6h); 1380 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1381 dsfield = orig_dsfield; 1382 else 1383 dsfield = ip6_tclass(t->parms.flowinfo); 1384 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1385 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1386 break; 1387 default: 1388 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo); 1389 break; 1390 } 1391 } 1392 1393 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1394 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield); 1395 1396 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1397 return -1; 1398 1399 skb_set_inner_ipproto(skb, protocol); 1400 1401 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1402 protocol); 1403 if (err != 0) { 1404 /* XXX: send ICMP error even if DF is not set. */ 1405 if (err == -EMSGSIZE) 1406 switch (protocol) { 1407 case IPPROTO_IPIP: 1408 icmp_ndo_send(skb, ICMP_DEST_UNREACH, 1409 ICMP_FRAG_NEEDED, htonl(mtu)); 1410 break; 1411 case IPPROTO_IPV6: 1412 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1413 break; 1414 default: 1415 break; 1416 } 1417 return -1; 1418 } 1419 1420 return 0; 1421 } 1422 1423 static netdev_tx_t 1424 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1425 { 1426 struct ip6_tnl *t = netdev_priv(dev); 1427 u8 ipproto; 1428 int ret; 1429 1430 if (!pskb_inet_may_pull(skb)) 1431 goto tx_err; 1432 1433 switch (skb->protocol) { 1434 case htons(ETH_P_IP): 1435 ipproto = IPPROTO_IPIP; 1436 break; 1437 case htons(ETH_P_IPV6): 1438 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb))) 1439 goto tx_err; 1440 ipproto = IPPROTO_IPV6; 1441 break; 1442 case htons(ETH_P_MPLS_UC): 1443 ipproto = IPPROTO_MPLS; 1444 break; 1445 default: 1446 goto tx_err; 1447 } 1448 1449 ret = ipxip6_tnl_xmit(skb, dev, ipproto); 1450 if (ret < 0) 1451 goto tx_err; 1452 1453 return NETDEV_TX_OK; 1454 1455 tx_err: 1456 DEV_STATS_INC(dev, tx_errors); 1457 DEV_STATS_INC(dev, tx_dropped); 1458 kfree_skb(skb); 1459 return NETDEV_TX_OK; 1460 } 1461 1462 static void ip6_tnl_link_config(struct ip6_tnl *t) 1463 { 1464 struct net_device *dev = t->dev; 1465 struct net_device *tdev = NULL; 1466 struct __ip6_tnl_parm *p = &t->parms; 1467 struct flowi6 *fl6 = &t->fl.u.ip6; 1468 int t_hlen; 1469 int mtu; 1470 1471 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr)); 1472 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1473 1474 /* Set up flowi template */ 1475 fl6->saddr = p->laddr; 1476 fl6->daddr = p->raddr; 1477 fl6->flowi6_oif = p->link; 1478 fl6->flowlabel = 0; 1479 1480 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1481 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1482 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1483 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1484 1485 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1486 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1487 1488 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1489 dev->flags |= IFF_POINTOPOINT; 1490 else 1491 dev->flags &= ~IFF_POINTOPOINT; 1492 1493 t->tun_hlen = 0; 1494 t->hlen = t->encap_hlen + t->tun_hlen; 1495 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1496 1497 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1498 int strict = (ipv6_addr_type(&p->raddr) & 1499 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1500 1501 struct rt6_info *rt = rt6_lookup(t->net, 1502 &p->raddr, &p->laddr, 1503 p->link, NULL, strict); 1504 if (rt) { 1505 tdev = rt->dst.dev; 1506 ip6_rt_put(rt); 1507 } 1508 1509 if (!tdev && p->link) 1510 tdev = __dev_get_by_index(t->net, p->link); 1511 1512 if (tdev) { 1513 dev->needed_headroom = tdev->hard_header_len + 1514 tdev->needed_headroom + t_hlen; 1515 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1516 1517 mtu = mtu - t_hlen; 1518 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1519 mtu -= 8; 1520 1521 if (mtu < IPV6_MIN_MTU) 1522 mtu = IPV6_MIN_MTU; 1523 WRITE_ONCE(dev->mtu, mtu); 1524 } 1525 } 1526 } 1527 1528 /** 1529 * ip6_tnl_change - update the tunnel parameters 1530 * @t: tunnel to be changed 1531 * @p: tunnel configuration parameters 1532 * 1533 * Description: 1534 * ip6_tnl_change() updates the tunnel parameters 1535 **/ 1536 1537 static void 1538 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1539 { 1540 t->parms.laddr = p->laddr; 1541 t->parms.raddr = p->raddr; 1542 t->parms.flags = p->flags; 1543 t->parms.hop_limit = p->hop_limit; 1544 t->parms.encap_limit = p->encap_limit; 1545 t->parms.flowinfo = p->flowinfo; 1546 t->parms.link = p->link; 1547 t->parms.proto = p->proto; 1548 t->parms.fwmark = p->fwmark; 1549 dst_cache_reset(&t->dst_cache); 1550 ip6_tnl_link_config(t); 1551 } 1552 1553 static void ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1554 { 1555 struct net *net = t->net; 1556 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1557 1558 ip6_tnl_unlink(ip6n, t); 1559 synchronize_net(); 1560 ip6_tnl_change(t, p); 1561 ip6_tnl_link(ip6n, t); 1562 netdev_state_change(t->dev); 1563 } 1564 1565 static void ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1566 { 1567 /* for default tnl0 device allow to change only the proto */ 1568 t->parms.proto = p->proto; 1569 netdev_state_change(t->dev); 1570 } 1571 1572 static void 1573 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1574 { 1575 p->laddr = u->laddr; 1576 p->raddr = u->raddr; 1577 p->flags = u->flags; 1578 p->hop_limit = u->hop_limit; 1579 p->encap_limit = u->encap_limit; 1580 p->flowinfo = u->flowinfo; 1581 p->link = u->link; 1582 p->proto = u->proto; 1583 memcpy(p->name, u->name, sizeof(u->name)); 1584 } 1585 1586 static void 1587 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1588 { 1589 u->laddr = p->laddr; 1590 u->raddr = p->raddr; 1591 u->flags = p->flags; 1592 u->hop_limit = p->hop_limit; 1593 u->encap_limit = p->encap_limit; 1594 u->flowinfo = p->flowinfo; 1595 u->link = p->link; 1596 u->proto = p->proto; 1597 memcpy(u->name, p->name, sizeof(u->name)); 1598 } 1599 1600 /** 1601 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace 1602 * @dev: virtual device associated with tunnel 1603 * @ifr: unused 1604 * @data: parameters passed from userspace 1605 * @cmd: command to be performed 1606 * 1607 * Description: 1608 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1609 * from userspace. 1610 * 1611 * The possible commands are the following: 1612 * %SIOCGETTUNNEL: get tunnel parameters for device 1613 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1614 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1615 * %SIOCDELTUNNEL: delete tunnel 1616 * 1617 * The fallback device "ip6tnl0", created during module 1618 * initialization, can be used for creating other tunnel devices. 1619 * 1620 * Return: 1621 * 0 on success, 1622 * %-EFAULT if unable to copy data to or from userspace, 1623 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1624 * %-EINVAL if passed tunnel parameters are invalid, 1625 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1626 * %-ENODEV if attempting to change or delete a nonexisting device 1627 **/ 1628 1629 static int 1630 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 1631 void __user *data, int cmd) 1632 { 1633 int err = 0; 1634 struct ip6_tnl_parm p; 1635 struct __ip6_tnl_parm p1; 1636 struct ip6_tnl *t = netdev_priv(dev); 1637 struct net *net = t->net; 1638 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1639 1640 memset(&p1, 0, sizeof(p1)); 1641 1642 switch (cmd) { 1643 case SIOCGETTUNNEL: 1644 if (dev == ip6n->fb_tnl_dev) { 1645 if (copy_from_user(&p, data, sizeof(p))) { 1646 err = -EFAULT; 1647 break; 1648 } 1649 ip6_tnl_parm_from_user(&p1, &p); 1650 t = ip6_tnl_locate(net, &p1, 0); 1651 if (IS_ERR(t)) 1652 t = netdev_priv(dev); 1653 } else { 1654 memset(&p, 0, sizeof(p)); 1655 } 1656 ip6_tnl_parm_to_user(&p, &t->parms); 1657 if (copy_to_user(data, &p, sizeof(p))) 1658 err = -EFAULT; 1659 break; 1660 case SIOCADDTUNNEL: 1661 case SIOCCHGTUNNEL: 1662 err = -EPERM; 1663 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1664 break; 1665 err = -EFAULT; 1666 if (copy_from_user(&p, data, sizeof(p))) 1667 break; 1668 err = -EINVAL; 1669 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1670 p.proto != 0) 1671 break; 1672 ip6_tnl_parm_from_user(&p1, &p); 1673 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1674 if (cmd == SIOCCHGTUNNEL) { 1675 if (!IS_ERR(t)) { 1676 if (t->dev != dev) { 1677 err = -EEXIST; 1678 break; 1679 } 1680 } else 1681 t = netdev_priv(dev); 1682 if (dev == ip6n->fb_tnl_dev) 1683 ip6_tnl0_update(t, &p1); 1684 else 1685 ip6_tnl_update(t, &p1); 1686 } 1687 if (!IS_ERR(t)) { 1688 err = 0; 1689 ip6_tnl_parm_to_user(&p, &t->parms); 1690 if (copy_to_user(data, &p, sizeof(p))) 1691 err = -EFAULT; 1692 1693 } else { 1694 err = PTR_ERR(t); 1695 } 1696 break; 1697 case SIOCDELTUNNEL: 1698 err = -EPERM; 1699 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1700 break; 1701 1702 if (dev == ip6n->fb_tnl_dev) { 1703 err = -EFAULT; 1704 if (copy_from_user(&p, data, sizeof(p))) 1705 break; 1706 err = -ENOENT; 1707 ip6_tnl_parm_from_user(&p1, &p); 1708 t = ip6_tnl_locate(net, &p1, 0); 1709 if (IS_ERR(t)) 1710 break; 1711 err = -EPERM; 1712 if (t->dev == ip6n->fb_tnl_dev) 1713 break; 1714 dev = t->dev; 1715 } 1716 err = 0; 1717 unregister_netdevice(dev); 1718 break; 1719 default: 1720 err = -EINVAL; 1721 } 1722 return err; 1723 } 1724 1725 /** 1726 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1727 * @dev: virtual device associated with tunnel 1728 * @new_mtu: the new mtu 1729 * 1730 * Return: 1731 * 0 on success, 1732 * %-EINVAL if mtu too small 1733 **/ 1734 1735 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1736 { 1737 struct ip6_tnl *tnl = netdev_priv(dev); 1738 int t_hlen; 1739 1740 t_hlen = tnl->hlen + sizeof(struct ipv6hdr); 1741 if (tnl->parms.proto == IPPROTO_IPV6) { 1742 if (new_mtu < IPV6_MIN_MTU) 1743 return -EINVAL; 1744 } else { 1745 if (new_mtu < ETH_MIN_MTU) 1746 return -EINVAL; 1747 } 1748 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1749 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len - t_hlen) 1750 return -EINVAL; 1751 } else { 1752 if (new_mtu > IP_MAX_MTU - dev->hard_header_len - t_hlen) 1753 return -EINVAL; 1754 } 1755 WRITE_ONCE(dev->mtu, new_mtu); 1756 return 0; 1757 } 1758 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1759 1760 int ip6_tnl_get_iflink(const struct net_device *dev) 1761 { 1762 struct ip6_tnl *t = netdev_priv(dev); 1763 1764 return READ_ONCE(t->parms.link); 1765 } 1766 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1767 1768 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1769 unsigned int num) 1770 { 1771 if (num >= MAX_IPTUN_ENCAP_OPS) 1772 return -ERANGE; 1773 1774 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1775 &ip6tun_encaps[num], 1776 NULL, ops) ? 0 : -1; 1777 } 1778 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1779 1780 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1781 unsigned int num) 1782 { 1783 int ret; 1784 1785 if (num >= MAX_IPTUN_ENCAP_OPS) 1786 return -ERANGE; 1787 1788 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1789 &ip6tun_encaps[num], 1790 ops, NULL) == ops) ? 0 : -1; 1791 1792 synchronize_net(); 1793 1794 return ret; 1795 } 1796 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1797 1798 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1799 struct ip_tunnel_encap *ipencap) 1800 { 1801 int hlen; 1802 1803 memset(&t->encap, 0, sizeof(t->encap)); 1804 1805 hlen = ip6_encap_hlen(ipencap); 1806 if (hlen < 0) 1807 return hlen; 1808 1809 t->encap.type = ipencap->type; 1810 t->encap.sport = ipencap->sport; 1811 t->encap.dport = ipencap->dport; 1812 t->encap.flags = ipencap->flags; 1813 1814 t->encap_hlen = hlen; 1815 t->hlen = t->encap_hlen + t->tun_hlen; 1816 1817 return 0; 1818 } 1819 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1820 1821 static const struct net_device_ops ip6_tnl_netdev_ops = { 1822 .ndo_init = ip6_tnl_dev_init, 1823 .ndo_uninit = ip6_tnl_dev_uninit, 1824 .ndo_start_xmit = ip6_tnl_start_xmit, 1825 .ndo_siocdevprivate = ip6_tnl_siocdevprivate, 1826 .ndo_change_mtu = ip6_tnl_change_mtu, 1827 .ndo_get_stats64 = dev_get_tstats64, 1828 .ndo_get_iflink = ip6_tnl_get_iflink, 1829 }; 1830 1831 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1832 NETIF_F_FRAGLIST | \ 1833 NETIF_F_HIGHDMA | \ 1834 NETIF_F_GSO_SOFTWARE | \ 1835 NETIF_F_HW_CSUM) 1836 1837 /** 1838 * ip6_tnl_dev_setup - setup virtual tunnel device 1839 * @dev: virtual device associated with tunnel 1840 * 1841 * Description: 1842 * Initialize function pointers and device parameters 1843 **/ 1844 1845 static void ip6_tnl_dev_setup(struct net_device *dev) 1846 { 1847 dev->netdev_ops = &ip6_tnl_netdev_ops; 1848 dev->header_ops = &ip_tunnel_header_ops; 1849 dev->needs_free_netdev = true; 1850 dev->priv_destructor = ip6_dev_free; 1851 1852 dev->type = ARPHRD_TUNNEL6; 1853 dev->flags |= IFF_NOARP; 1854 dev->addr_len = sizeof(struct in6_addr); 1855 dev->lltx = true; 1856 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; 1857 netif_keep_dst(dev); 1858 1859 dev->features |= IPXIPX_FEATURES; 1860 dev->hw_features |= IPXIPX_FEATURES; 1861 1862 /* This perm addr will be used as interface identifier by IPv6 */ 1863 dev->addr_assign_type = NET_ADDR_RANDOM; 1864 eth_random_addr(dev->perm_addr); 1865 } 1866 1867 1868 /** 1869 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1870 * @dev: virtual device associated with tunnel 1871 **/ 1872 1873 static inline int 1874 ip6_tnl_dev_init_gen(struct net_device *dev) 1875 { 1876 struct ip6_tnl *t = netdev_priv(dev); 1877 int ret; 1878 int t_hlen; 1879 1880 t->dev = dev; 1881 t->net = dev_net(dev); 1882 1883 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1884 if (ret) 1885 return ret; 1886 1887 ret = gro_cells_init(&t->gro_cells, dev); 1888 if (ret) 1889 goto destroy_dst; 1890 1891 t->tun_hlen = 0; 1892 t->hlen = t->encap_hlen + t->tun_hlen; 1893 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1894 1895 dev->type = ARPHRD_TUNNEL6; 1896 dev->mtu = ETH_DATA_LEN - t_hlen; 1897 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1898 dev->mtu -= 8; 1899 dev->min_mtu = ETH_MIN_MTU; 1900 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len - t_hlen; 1901 1902 netdev_hold(dev, &t->dev_tracker, GFP_KERNEL); 1903 netdev_lockdep_set_classes(dev); 1904 return 0; 1905 1906 destroy_dst: 1907 dst_cache_destroy(&t->dst_cache); 1908 1909 return ret; 1910 } 1911 1912 /** 1913 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1914 * @dev: virtual device associated with tunnel 1915 **/ 1916 1917 static int ip6_tnl_dev_init(struct net_device *dev) 1918 { 1919 struct ip6_tnl *t = netdev_priv(dev); 1920 int err = ip6_tnl_dev_init_gen(dev); 1921 1922 if (err) 1923 return err; 1924 ip6_tnl_link_config(t); 1925 if (t->parms.collect_md) 1926 netif_keep_dst(dev); 1927 return 0; 1928 } 1929 1930 /** 1931 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1932 * @dev: fallback device 1933 * 1934 * Return: 0 1935 **/ 1936 1937 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1938 { 1939 struct ip6_tnl *t = netdev_priv(dev); 1940 struct net *net = dev_net(dev); 1941 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1942 1943 t->parms.proto = IPPROTO_IPV6; 1944 1945 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1946 return 0; 1947 } 1948 1949 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1950 struct netlink_ext_ack *extack) 1951 { 1952 u8 proto; 1953 1954 if (!data || !data[IFLA_IPTUN_PROTO]) 1955 return 0; 1956 1957 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1958 if (proto != IPPROTO_IPV6 && 1959 proto != IPPROTO_IPIP && 1960 proto != 0) 1961 return -EINVAL; 1962 1963 return 0; 1964 } 1965 1966 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1967 struct __ip6_tnl_parm *parms) 1968 { 1969 memset(parms, 0, sizeof(*parms)); 1970 1971 if (!data) 1972 return; 1973 1974 if (data[IFLA_IPTUN_LINK]) 1975 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1976 1977 if (data[IFLA_IPTUN_LOCAL]) 1978 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1979 1980 if (data[IFLA_IPTUN_REMOTE]) 1981 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1982 1983 if (data[IFLA_IPTUN_TTL]) 1984 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1985 1986 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1987 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1988 1989 if (data[IFLA_IPTUN_FLOWINFO]) 1990 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1991 1992 if (data[IFLA_IPTUN_FLAGS]) 1993 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1994 1995 if (data[IFLA_IPTUN_PROTO]) 1996 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1997 1998 if (data[IFLA_IPTUN_COLLECT_METADATA]) 1999 parms->collect_md = true; 2000 2001 if (data[IFLA_IPTUN_FWMARK]) 2002 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 2003 } 2004 2005 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 2006 struct nlattr *tb[], struct nlattr *data[], 2007 struct netlink_ext_ack *extack) 2008 { 2009 struct net *net = dev_net(dev); 2010 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2011 struct ip_tunnel_encap ipencap; 2012 struct ip6_tnl *nt, *t; 2013 int err; 2014 2015 nt = netdev_priv(dev); 2016 2017 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2018 err = ip6_tnl_encap_setup(nt, &ipencap); 2019 if (err < 0) 2020 return err; 2021 } 2022 2023 ip6_tnl_netlink_parms(data, &nt->parms); 2024 2025 if (nt->parms.collect_md) { 2026 if (rtnl_dereference(ip6n->collect_md_tun)) 2027 return -EEXIST; 2028 } else { 2029 t = ip6_tnl_locate(net, &nt->parms, 0); 2030 if (!IS_ERR(t)) 2031 return -EEXIST; 2032 } 2033 2034 err = ip6_tnl_create2(dev); 2035 if (!err && tb[IFLA_MTU]) 2036 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2037 2038 return err; 2039 } 2040 2041 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2042 struct nlattr *data[], 2043 struct netlink_ext_ack *extack) 2044 { 2045 struct ip6_tnl *t = netdev_priv(dev); 2046 struct __ip6_tnl_parm p; 2047 struct net *net = t->net; 2048 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2049 struct ip_tunnel_encap ipencap; 2050 2051 if (dev == ip6n->fb_tnl_dev) 2052 return -EINVAL; 2053 2054 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2055 int err = ip6_tnl_encap_setup(t, &ipencap); 2056 2057 if (err < 0) 2058 return err; 2059 } 2060 ip6_tnl_netlink_parms(data, &p); 2061 if (p.collect_md) 2062 return -EINVAL; 2063 2064 t = ip6_tnl_locate(net, &p, 0); 2065 if (!IS_ERR(t)) { 2066 if (t->dev != dev) 2067 return -EEXIST; 2068 } else 2069 t = netdev_priv(dev); 2070 2071 ip6_tnl_update(t, &p); 2072 return 0; 2073 } 2074 2075 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2076 { 2077 struct net *net = dev_net(dev); 2078 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2079 2080 if (dev != ip6n->fb_tnl_dev) 2081 unregister_netdevice_queue(dev, head); 2082 } 2083 2084 static size_t ip6_tnl_get_size(const struct net_device *dev) 2085 { 2086 return 2087 /* IFLA_IPTUN_LINK */ 2088 nla_total_size(4) + 2089 /* IFLA_IPTUN_LOCAL */ 2090 nla_total_size(sizeof(struct in6_addr)) + 2091 /* IFLA_IPTUN_REMOTE */ 2092 nla_total_size(sizeof(struct in6_addr)) + 2093 /* IFLA_IPTUN_TTL */ 2094 nla_total_size(1) + 2095 /* IFLA_IPTUN_ENCAP_LIMIT */ 2096 nla_total_size(1) + 2097 /* IFLA_IPTUN_FLOWINFO */ 2098 nla_total_size(4) + 2099 /* IFLA_IPTUN_FLAGS */ 2100 nla_total_size(4) + 2101 /* IFLA_IPTUN_PROTO */ 2102 nla_total_size(1) + 2103 /* IFLA_IPTUN_ENCAP_TYPE */ 2104 nla_total_size(2) + 2105 /* IFLA_IPTUN_ENCAP_FLAGS */ 2106 nla_total_size(2) + 2107 /* IFLA_IPTUN_ENCAP_SPORT */ 2108 nla_total_size(2) + 2109 /* IFLA_IPTUN_ENCAP_DPORT */ 2110 nla_total_size(2) + 2111 /* IFLA_IPTUN_COLLECT_METADATA */ 2112 nla_total_size(0) + 2113 /* IFLA_IPTUN_FWMARK */ 2114 nla_total_size(4) + 2115 0; 2116 } 2117 2118 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2119 { 2120 struct ip6_tnl *tunnel = netdev_priv(dev); 2121 struct __ip6_tnl_parm *parm = &tunnel->parms; 2122 2123 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2124 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2125 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2126 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2127 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2128 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2129 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2130 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2131 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2132 goto nla_put_failure; 2133 2134 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2135 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2136 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2137 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2138 goto nla_put_failure; 2139 2140 if (parm->collect_md) 2141 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2142 goto nla_put_failure; 2143 2144 return 0; 2145 2146 nla_put_failure: 2147 return -EMSGSIZE; 2148 } 2149 2150 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2151 { 2152 struct ip6_tnl *tunnel = netdev_priv(dev); 2153 2154 return READ_ONCE(tunnel->net); 2155 } 2156 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2157 2158 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2159 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2160 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2161 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2162 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2163 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2164 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2165 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2166 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2167 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2168 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2169 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2170 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2171 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2172 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2173 }; 2174 2175 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2176 .kind = "ip6tnl", 2177 .maxtype = IFLA_IPTUN_MAX, 2178 .policy = ip6_tnl_policy, 2179 .priv_size = sizeof(struct ip6_tnl), 2180 .setup = ip6_tnl_dev_setup, 2181 .validate = ip6_tnl_validate, 2182 .newlink = ip6_tnl_newlink, 2183 .changelink = ip6_tnl_changelink, 2184 .dellink = ip6_tnl_dellink, 2185 .get_size = ip6_tnl_get_size, 2186 .fill_info = ip6_tnl_fill_info, 2187 .get_link_net = ip6_tnl_get_link_net, 2188 }; 2189 2190 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2191 .handler = ip4ip6_rcv, 2192 .err_handler = ip4ip6_err, 2193 .priority = 1, 2194 }; 2195 2196 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2197 .handler = ip6ip6_rcv, 2198 .err_handler = ip6ip6_err, 2199 .priority = 1, 2200 }; 2201 2202 static struct xfrm6_tunnel mplsip6_handler __read_mostly = { 2203 .handler = mplsip6_rcv, 2204 .err_handler = mplsip6_err, 2205 .priority = 1, 2206 }; 2207 2208 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2209 { 2210 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2211 struct net_device *dev, *aux; 2212 int h; 2213 struct ip6_tnl *t; 2214 2215 for_each_netdev_safe(net, dev, aux) 2216 if (dev->rtnl_link_ops == &ip6_link_ops) 2217 unregister_netdevice_queue(dev, list); 2218 2219 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2220 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2221 while (t) { 2222 /* If dev is in the same netns, it has already 2223 * been added to the list by the previous loop. 2224 */ 2225 if (!net_eq(dev_net(t->dev), net)) 2226 unregister_netdevice_queue(t->dev, list); 2227 t = rtnl_dereference(t->next); 2228 } 2229 } 2230 2231 t = rtnl_dereference(ip6n->tnls_wc[0]); 2232 while (t) { 2233 /* If dev is in the same netns, it has already 2234 * been added to the list by the previous loop. 2235 */ 2236 if (!net_eq(dev_net(t->dev), net)) 2237 unregister_netdevice_queue(t->dev, list); 2238 t = rtnl_dereference(t->next); 2239 } 2240 } 2241 2242 static int __net_init ip6_tnl_init_net(struct net *net) 2243 { 2244 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2245 struct ip6_tnl *t = NULL; 2246 int err; 2247 2248 ip6n->tnls[0] = ip6n->tnls_wc; 2249 ip6n->tnls[1] = ip6n->tnls_r_l; 2250 2251 if (!net_has_fallback_tunnels(net)) 2252 return 0; 2253 err = -ENOMEM; 2254 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2255 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2256 2257 if (!ip6n->fb_tnl_dev) 2258 goto err_alloc_dev; 2259 dev_net_set(ip6n->fb_tnl_dev, net); 2260 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2261 /* FB netdevice is special: we have one, and only one per netns. 2262 * Allowing to move it to another netns is clearly unsafe. 2263 */ 2264 ip6n->fb_tnl_dev->netns_local = true; 2265 2266 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2267 if (err < 0) 2268 goto err_register; 2269 2270 err = register_netdev(ip6n->fb_tnl_dev); 2271 if (err < 0) 2272 goto err_register; 2273 2274 t = netdev_priv(ip6n->fb_tnl_dev); 2275 2276 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2277 return 0; 2278 2279 err_register: 2280 free_netdev(ip6n->fb_tnl_dev); 2281 err_alloc_dev: 2282 return err; 2283 } 2284 2285 static void __net_exit ip6_tnl_exit_batch_rtnl(struct list_head *net_list, 2286 struct list_head *dev_to_kill) 2287 { 2288 struct net *net; 2289 2290 ASSERT_RTNL(); 2291 list_for_each_entry(net, net_list, exit_list) 2292 ip6_tnl_destroy_tunnels(net, dev_to_kill); 2293 } 2294 2295 static struct pernet_operations ip6_tnl_net_ops = { 2296 .init = ip6_tnl_init_net, 2297 .exit_batch_rtnl = ip6_tnl_exit_batch_rtnl, 2298 .id = &ip6_tnl_net_id, 2299 .size = sizeof(struct ip6_tnl_net), 2300 }; 2301 2302 /** 2303 * ip6_tunnel_init - register protocol and reserve needed resources 2304 * 2305 * Return: 0 on success 2306 **/ 2307 2308 static int __init ip6_tunnel_init(void) 2309 { 2310 int err; 2311 2312 if (!ipv6_mod_enabled()) 2313 return -EOPNOTSUPP; 2314 2315 err = register_pernet_device(&ip6_tnl_net_ops); 2316 if (err < 0) 2317 goto out_pernet; 2318 2319 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2320 if (err < 0) { 2321 pr_err("%s: can't register ip4ip6\n", __func__); 2322 goto out_ip4ip6; 2323 } 2324 2325 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2326 if (err < 0) { 2327 pr_err("%s: can't register ip6ip6\n", __func__); 2328 goto out_ip6ip6; 2329 } 2330 2331 if (ip6_tnl_mpls_supported()) { 2332 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS); 2333 if (err < 0) { 2334 pr_err("%s: can't register mplsip6\n", __func__); 2335 goto out_mplsip6; 2336 } 2337 } 2338 2339 err = rtnl_link_register(&ip6_link_ops); 2340 if (err < 0) 2341 goto rtnl_link_failed; 2342 2343 return 0; 2344 2345 rtnl_link_failed: 2346 if (ip6_tnl_mpls_supported()) 2347 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS); 2348 out_mplsip6: 2349 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2350 out_ip6ip6: 2351 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2352 out_ip4ip6: 2353 unregister_pernet_device(&ip6_tnl_net_ops); 2354 out_pernet: 2355 return err; 2356 } 2357 2358 /** 2359 * ip6_tunnel_cleanup - free resources and unregister protocol 2360 **/ 2361 2362 static void __exit ip6_tunnel_cleanup(void) 2363 { 2364 rtnl_link_unregister(&ip6_link_ops); 2365 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2366 pr_info("%s: can't deregister ip4ip6\n", __func__); 2367 2368 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2369 pr_info("%s: can't deregister ip6ip6\n", __func__); 2370 2371 if (ip6_tnl_mpls_supported() && 2372 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS)) 2373 pr_info("%s: can't deregister mplsip6\n", __func__); 2374 unregister_pernet_device(&ip6_tnl_net_ops); 2375 } 2376 2377 module_init(ip6_tunnel_init); 2378 module_exit(ip6_tunnel_cleanup); 2379