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/netdev_lock.h> 56 #include <net/dst_metadata.h> 57 #include <net/inet_dscp.h> 58 59 MODULE_AUTHOR("Ville Nuorvala"); 60 MODULE_DESCRIPTION("IPv6 tunneling device"); 61 MODULE_LICENSE("GPL"); 62 MODULE_ALIAS_RTNL_LINK("ip6tnl"); 63 MODULE_ALIAS_NETDEV("ip6tnl0"); 64 65 #define IP6_TUNNEL_HASH_SIZE_SHIFT 5 66 #define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT) 67 68 static bool log_ecn_error = true; 69 module_param(log_ecn_error, bool, 0644); 70 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 71 72 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) 73 { 74 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); 75 76 return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT); 77 } 78 79 static int ip6_tnl_dev_init(struct net_device *dev); 80 static void ip6_tnl_dev_setup(struct net_device *dev); 81 static struct rtnl_link_ops ip6_link_ops __read_mostly; 82 83 static unsigned int ip6_tnl_net_id __read_mostly; 84 struct ip6_tnl_net { 85 /* the IPv6 tunnel fallback device */ 86 struct net_device *fb_tnl_dev; 87 /* lists for storing tunnels in use */ 88 struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE]; 89 struct ip6_tnl __rcu *tnls_wc[1]; 90 struct ip6_tnl __rcu **tnls[2]; 91 struct ip6_tnl __rcu *collect_md_tun; 92 }; 93 94 static inline int ip6_tnl_mpls_supported(void) 95 { 96 return IS_ENABLED(CONFIG_MPLS); 97 } 98 99 #define for_each_ip6_tunnel_rcu(start) \ 100 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 101 102 /** 103 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 104 * @net: network namespace 105 * @link: ifindex of underlying interface 106 * @remote: the address of the tunnel exit-point 107 * @local: the address of the tunnel entry-point 108 * 109 * Return: 110 * tunnel matching given end-points if found, 111 * else fallback tunnel if its device is up, 112 * else %NULL 113 **/ 114 115 static struct ip6_tnl * 116 ip6_tnl_lookup(struct net *net, int link, 117 const struct in6_addr *remote, const struct in6_addr *local) 118 { 119 unsigned int hash = HASH(remote, local); 120 struct ip6_tnl *t, *cand = NULL; 121 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 122 struct in6_addr any; 123 124 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 125 if (!ipv6_addr_equal(local, &t->parms.laddr) || 126 !ipv6_addr_equal(remote, &t->parms.raddr) || 127 !(t->dev->flags & IFF_UP)) 128 continue; 129 130 if (link == t->parms.link) 131 return t; 132 else 133 cand = t; 134 } 135 136 memset(&any, 0, sizeof(any)); 137 hash = HASH(&any, local); 138 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 139 if (!ipv6_addr_equal(local, &t->parms.laddr) || 140 !ipv6_addr_any(&t->parms.raddr) || 141 !(t->dev->flags & IFF_UP)) 142 continue; 143 144 if (link == t->parms.link) 145 return t; 146 else if (!cand) 147 cand = t; 148 } 149 150 hash = HASH(remote, &any); 151 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 152 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 153 !ipv6_addr_any(&t->parms.laddr) || 154 !(t->dev->flags & IFF_UP)) 155 continue; 156 157 if (link == t->parms.link) 158 return t; 159 else if (!cand) 160 cand = t; 161 } 162 163 if (cand) 164 return cand; 165 166 t = rcu_dereference(ip6n->collect_md_tun); 167 if (t && t->dev->flags & IFF_UP) 168 return t; 169 170 t = rcu_dereference(ip6n->tnls_wc[0]); 171 if (t && (t->dev->flags & IFF_UP)) 172 return t; 173 174 return NULL; 175 } 176 177 /** 178 * ip6_tnl_bucket - get head of list matching given tunnel parameters 179 * @ip6n: the private data for ip6_vti in the netns 180 * @p: parameters containing tunnel end-points 181 * 182 * Description: 183 * ip6_tnl_bucket() returns the head of the list matching the 184 * &struct in6_addr entries laddr and raddr in @p. 185 * 186 * Return: head of IPv6 tunnel list 187 **/ 188 189 static struct ip6_tnl __rcu ** 190 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p) 191 { 192 const struct in6_addr *remote = &p->raddr; 193 const struct in6_addr *local = &p->laddr; 194 unsigned int h = 0; 195 int prio = 0; 196 197 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 198 prio = 1; 199 h = HASH(remote, local); 200 } 201 return &ip6n->tnls[prio][h]; 202 } 203 204 /** 205 * ip6_tnl_link - add tunnel to hash table 206 * @ip6n: the private data for ip6_vti in the netns 207 * @t: tunnel to be added 208 **/ 209 210 static void 211 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 212 { 213 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); 214 215 if (t->parms.collect_md) 216 rcu_assign_pointer(ip6n->collect_md_tun, t); 217 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 218 rcu_assign_pointer(*tp, t); 219 } 220 221 /** 222 * ip6_tnl_unlink - remove tunnel from hash table 223 * @ip6n: the private data for ip6_vti in the netns 224 * @t: tunnel to be removed 225 **/ 226 227 static void 228 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 229 { 230 struct ip6_tnl __rcu **tp; 231 struct ip6_tnl *iter; 232 233 if (t->parms.collect_md) 234 rcu_assign_pointer(ip6n->collect_md_tun, NULL); 235 236 for (tp = ip6_tnl_bucket(ip6n, &t->parms); 237 (iter = rtnl_dereference(*tp)) != NULL; 238 tp = &iter->next) { 239 if (t == iter) { 240 rcu_assign_pointer(*tp, t->next); 241 break; 242 } 243 } 244 } 245 246 static void ip6_dev_free(struct net_device *dev) 247 { 248 struct ip6_tnl *t = netdev_priv(dev); 249 250 gro_cells_destroy(&t->gro_cells); 251 dst_cache_destroy(&t->dst_cache); 252 } 253 254 static int ip6_tnl_create2(struct net_device *dev) 255 { 256 struct ip6_tnl *t = netdev_priv(dev); 257 struct ip6_tnl_net *ip6n = net_generic(t->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 /* Remove debris left by IPv6 stack. */ 605 memset(IPCB(skb2), 0, sizeof(*IPCB(skb2))); 606 607 skb_dst_drop(skb2); 608 609 skb_pull(skb2, offset); 610 skb_reset_network_header(skb2); 611 eiph = ip_hdr(skb2); 612 if (eiph->version != 4 || eiph->ihl < 5) 613 goto out; 614 615 /* Try to guess incoming interface */ 616 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr, 617 0, 0, 0, IPPROTO_IPIP, 618 eiph->tos & INET_DSCP_MASK, 0); 619 if (IS_ERR(rt)) 620 goto out; 621 622 skb2->dev = rt->dst.dev; 623 ip_rt_put(rt); 624 625 /* route "incoming" packet */ 626 if (rt->rt_flags & RTCF_LOCAL) { 627 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 628 eiph->daddr, eiph->saddr, 0, 0, 629 IPPROTO_IPIP, 630 eiph->tos & INET_DSCP_MASK, 0); 631 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) { 632 if (!IS_ERR(rt)) 633 ip_rt_put(rt); 634 goto out; 635 } 636 skb_dst_set(skb2, &rt->dst); 637 } else { 638 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, 639 ip4h_dscp(eiph), skb2->dev) || 640 skb_dst_dev(skb2)->type != ARPHRD_TUNNEL6) 641 goto out; 642 } 643 644 /* change mtu on this route */ 645 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 646 if (rel_info > dst6_mtu(skb_dst(skb2))) 647 goto out; 648 649 skb_dst_update_pmtu_no_confirm(skb2, rel_info); 650 } 651 652 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 653 654 out: 655 kfree_skb(skb2); 656 return 0; 657 } 658 659 static int 660 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 661 u8 type, u8 code, int offset, __be32 info) 662 { 663 __u32 rel_info = ntohl(info); 664 int err, rel_msg = 0; 665 u8 rel_type = type; 666 u8 rel_code = code; 667 668 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 669 &rel_msg, &rel_info, offset); 670 if (err < 0) 671 return err; 672 673 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 674 struct rt6_info *rt; 675 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 676 677 if (!skb2) 678 return 0; 679 680 skb_dst_drop(skb2); 681 skb_pull(skb2, offset); 682 skb_reset_network_header(skb2); 683 684 /* Try to guess incoming interface */ 685 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 686 NULL, 0, skb2, 0); 687 688 if (rt && rt->dst.dev) 689 skb2->dev = rt->dst.dev; 690 691 icmpv6_send(skb2, rel_type, rel_code, rel_info); 692 693 ip6_rt_put(rt); 694 695 kfree_skb(skb2); 696 } 697 698 return 0; 699 } 700 701 static int 702 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 703 u8 type, u8 code, int offset, __be32 info) 704 { 705 __u32 rel_info = ntohl(info); 706 int err, rel_msg = 0; 707 u8 rel_type = type; 708 u8 rel_code = code; 709 710 err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code, 711 &rel_msg, &rel_info, offset); 712 return err; 713 } 714 715 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 716 const struct ipv6hdr *ipv6h, 717 struct sk_buff *skb) 718 { 719 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 720 721 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 722 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 723 724 return IP6_ECN_decapsulate(ipv6h, skb); 725 } 726 727 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 728 const struct ipv6hdr *ipv6h, 729 struct sk_buff *skb) 730 { 731 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 732 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 733 734 return IP6_ECN_decapsulate(ipv6h, skb); 735 } 736 737 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 738 const struct ipv6hdr *ipv6h, 739 struct sk_buff *skb) 740 { 741 /* ECN is not supported in AF_MPLS */ 742 return 0; 743 } 744 745 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 746 const struct in6_addr *laddr, 747 const struct in6_addr *raddr) 748 { 749 struct __ip6_tnl_parm *p = &t->parms; 750 int ltype = ipv6_addr_type(laddr); 751 int rtype = ipv6_addr_type(raddr); 752 __u32 flags = 0; 753 754 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 755 flags = IP6_TNL_F_CAP_PER_PACKET; 756 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 757 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 758 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 759 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 760 if (ltype&IPV6_ADDR_UNICAST) 761 flags |= IP6_TNL_F_CAP_XMIT; 762 if (rtype&IPV6_ADDR_UNICAST) 763 flags |= IP6_TNL_F_CAP_RCV; 764 } 765 return flags; 766 } 767 EXPORT_SYMBOL(ip6_tnl_get_cap); 768 769 /* called with rcu_read_lock() */ 770 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 771 const struct in6_addr *laddr, 772 const struct in6_addr *raddr) 773 { 774 struct __ip6_tnl_parm *p = &t->parms; 775 int ret = 0; 776 struct net *net = t->net; 777 778 if ((p->flags & IP6_TNL_F_CAP_RCV) || 779 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 780 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 781 struct net_device *ldev = NULL; 782 783 if (p->link) 784 ldev = dev_get_by_index_rcu(net, p->link); 785 786 if ((ipv6_addr_is_multicast(laddr) || 787 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false, 788 0, IFA_F_TENTATIVE))) && 789 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) || 790 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true, 791 0, IFA_F_TENTATIVE)))) 792 ret = 1; 793 } 794 return ret; 795 } 796 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 797 798 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb, 799 const struct tnl_ptk_info *tpi, 800 struct metadata_dst *tun_dst, 801 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 802 const struct ipv6hdr *ipv6h, 803 struct sk_buff *skb), 804 bool log_ecn_err) 805 { 806 const struct ipv6hdr *ipv6h; 807 int nh, err; 808 809 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.i_flags) != 810 test_bit(IP_TUNNEL_CSUM_BIT, tpi->flags)) { 811 DEV_STATS_INC(tunnel->dev, rx_crc_errors); 812 DEV_STATS_INC(tunnel->dev, rx_errors); 813 goto drop; 814 } 815 816 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.i_flags)) { 817 if (!test_bit(IP_TUNNEL_SEQ_BIT, tpi->flags) || 818 (tunnel->i_seqno && 819 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 820 DEV_STATS_INC(tunnel->dev, rx_fifo_errors); 821 DEV_STATS_INC(tunnel->dev, rx_errors); 822 goto drop; 823 } 824 tunnel->i_seqno = ntohl(tpi->seq) + 1; 825 } 826 827 skb->protocol = tpi->proto; 828 829 /* Warning: All skb pointers will be invalidated! */ 830 if (tunnel->dev->type == ARPHRD_ETHER) { 831 if (!pskb_may_pull(skb, ETH_HLEN)) { 832 DEV_STATS_INC(tunnel->dev, rx_length_errors); 833 DEV_STATS_INC(tunnel->dev, rx_errors); 834 goto drop; 835 } 836 837 skb->protocol = eth_type_trans(skb, tunnel->dev); 838 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 839 } else { 840 skb->dev = tunnel->dev; 841 skb_reset_mac_header(skb); 842 } 843 844 /* Save offset of outer header relative to skb->head, 845 * because we are going to reset the network header to the inner header 846 * and might change skb->head. 847 */ 848 nh = skb_network_header(skb) - skb->head; 849 850 skb_reset_network_header(skb); 851 852 if (skb_vlan_inet_prepare(skb, true)) { 853 DEV_STATS_INC(tunnel->dev, rx_length_errors); 854 DEV_STATS_INC(tunnel->dev, rx_errors); 855 goto drop; 856 } 857 858 /* Get the outer header. */ 859 ipv6h = (struct ipv6hdr *)(skb->head + nh); 860 861 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 862 863 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 864 865 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 866 if (unlikely(err)) { 867 if (log_ecn_err) 868 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 869 &ipv6h->saddr, 870 ipv6_get_dsfield(ipv6h)); 871 if (err > 1) { 872 DEV_STATS_INC(tunnel->dev, rx_frame_errors); 873 DEV_STATS_INC(tunnel->dev, rx_errors); 874 goto drop; 875 } 876 } 877 878 dev_sw_netstats_rx_add(tunnel->dev, skb->len); 879 880 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 881 882 if (tun_dst) 883 skb_dst_set(skb, (struct dst_entry *)tun_dst); 884 885 gro_cells_receive(&tunnel->gro_cells, skb); 886 return 0; 887 888 drop: 889 if (tun_dst) 890 dst_release((struct dst_entry *)tun_dst); 891 kfree_skb(skb); 892 return 0; 893 } 894 895 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 896 const struct tnl_ptk_info *tpi, 897 struct metadata_dst *tun_dst, 898 bool log_ecn_err) 899 { 900 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 901 const struct ipv6hdr *ipv6h, 902 struct sk_buff *skb); 903 904 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate; 905 if (tpi->proto == htons(ETH_P_IP)) 906 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate; 907 908 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 909 log_ecn_err); 910 } 911 EXPORT_SYMBOL(ip6_tnl_rcv); 912 913 static const struct tnl_ptk_info tpi_v6 = { 914 /* no tunnel info required for ipxip6. */ 915 .proto = htons(ETH_P_IPV6), 916 }; 917 918 static const struct tnl_ptk_info tpi_v4 = { 919 /* no tunnel info required for ipxip6. */ 920 .proto = htons(ETH_P_IP), 921 }; 922 923 static const struct tnl_ptk_info tpi_mpls = { 924 /* no tunnel info required for mplsip6. */ 925 .proto = htons(ETH_P_MPLS_UC), 926 }; 927 928 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 929 const struct tnl_ptk_info *tpi, 930 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 931 const struct ipv6hdr *ipv6h, 932 struct sk_buff *skb)) 933 { 934 struct ip6_tnl *t; 935 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 936 struct metadata_dst *tun_dst = NULL; 937 int ret = -1; 938 939 rcu_read_lock(); 940 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr); 941 942 if (t) { 943 u8 tproto = READ_ONCE(t->parms.proto); 944 945 if (tproto != ipproto && tproto != 0) 946 goto drop; 947 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 948 goto drop; 949 ipv6h = ipv6_hdr(skb); 950 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 951 goto drop; 952 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 953 goto drop; 954 if (t->parms.collect_md) { 955 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 956 957 tun_dst = ipv6_tun_rx_dst(skb, flags, 0, 0); 958 if (!tun_dst) 959 goto drop; 960 } 961 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 962 log_ecn_error); 963 } 964 965 rcu_read_unlock(); 966 967 return ret; 968 969 drop: 970 rcu_read_unlock(); 971 kfree_skb(skb); 972 return 0; 973 } 974 975 static int ip4ip6_rcv(struct sk_buff *skb) 976 { 977 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 978 ip4ip6_dscp_ecn_decapsulate); 979 } 980 981 static int ip6ip6_rcv(struct sk_buff *skb) 982 { 983 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 984 ip6ip6_dscp_ecn_decapsulate); 985 } 986 987 static int mplsip6_rcv(struct sk_buff *skb) 988 { 989 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls, 990 mplsip6_dscp_ecn_decapsulate); 991 } 992 993 struct ipv6_tel_txoption { 994 struct ipv6_txoptions ops; 995 __u8 dst_opt[8]; 996 }; 997 998 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 999 { 1000 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 1001 1002 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 1003 opt->dst_opt[3] = 1; 1004 opt->dst_opt[4] = encap_limit; 1005 opt->dst_opt[5] = IPV6_TLV_PADN; 1006 opt->dst_opt[6] = 1; 1007 1008 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 1009 opt->ops.opt_nflen = 8; 1010 } 1011 1012 /** 1013 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 1014 * @t: the outgoing tunnel device 1015 * @hdr: IPv6 header from the incoming packet 1016 * 1017 * Description: 1018 * Avoid trivial tunneling loop by checking that tunnel exit-point 1019 * doesn't match source of incoming packet. 1020 * 1021 * Return: 1022 * 1 if conflict, 1023 * 0 else 1024 **/ 1025 1026 static inline bool 1027 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 1028 { 1029 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 1030 } 1031 1032 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 1033 const struct in6_addr *laddr, 1034 const struct in6_addr *raddr) 1035 { 1036 struct __ip6_tnl_parm *p = &t->parms; 1037 int ret = 0; 1038 struct net *net = t->net; 1039 1040 if (t->parms.collect_md) 1041 return 1; 1042 1043 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 1044 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 1045 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 1046 struct net_device *ldev = NULL; 1047 1048 rcu_read_lock(); 1049 if (p->link) 1050 ldev = dev_get_by_index_rcu(net, p->link); 1051 1052 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1053 0, IFA_F_TENTATIVE))) 1054 pr_warn_ratelimited("%s xmit: Local address not yet configured!\n", 1055 p->name); 1056 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1057 !ipv6_addr_is_multicast(raddr) && 1058 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1059 true, 0, IFA_F_TENTATIVE))) 1060 pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n", 1061 p->name); 1062 else 1063 ret = 1; 1064 rcu_read_unlock(); 1065 } 1066 return ret; 1067 } 1068 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1069 1070 /** 1071 * ip6_tnl_xmit - encapsulate packet and send 1072 * @skb: the outgoing socket buffer 1073 * @dev: the outgoing tunnel device 1074 * @dsfield: dscp code for outer header 1075 * @fl6: flow of tunneled packet 1076 * @encap_limit: encapsulation limit 1077 * @pmtu: Path MTU is stored if packet is too big 1078 * @proto: next header value 1079 * 1080 * Description: 1081 * Build new header and do some sanity checks on the packet before sending 1082 * it. 1083 * 1084 * Return: 1085 * 0 on success 1086 * -1 fail 1087 * %-EMSGSIZE message too big. return mtu in this case. 1088 **/ 1089 1090 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1091 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1092 __u8 proto) 1093 { 1094 struct ip6_tnl *t = netdev_priv(dev); 1095 struct net *net = t->net; 1096 struct ipv6hdr *ipv6h; 1097 struct ipv6_tel_txoption opt; 1098 struct dst_entry *dst = NULL, *ndst = NULL; 1099 struct net_device *tdev; 1100 int mtu; 1101 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1102 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1103 unsigned int max_headroom = psh_hlen; 1104 __be16 payload_protocol; 1105 bool use_cache = false; 1106 u8 hop_limit; 1107 int err = -1; 1108 1109 payload_protocol = skb_protocol(skb, true); 1110 1111 if (t->parms.collect_md) { 1112 hop_limit = skb_tunnel_info(skb)->key.ttl; 1113 goto route_lookup; 1114 } else { 1115 hop_limit = t->parms.hop_limit; 1116 } 1117 1118 /* NBMA tunnel */ 1119 if (ipv6_addr_any(&t->parms.raddr)) { 1120 if (payload_protocol == htons(ETH_P_IPV6)) { 1121 struct in6_addr *addr6; 1122 struct neighbour *neigh; 1123 int addr_type; 1124 1125 if (!skb_dst(skb)) 1126 goto tx_err_link_failure; 1127 1128 neigh = dst_neigh_lookup(skb_dst(skb), 1129 &ipv6_hdr(skb)->daddr); 1130 if (!neigh) 1131 goto tx_err_link_failure; 1132 1133 addr6 = (struct in6_addr *)&neigh->primary_key; 1134 addr_type = ipv6_addr_type(addr6); 1135 1136 if (addr_type == IPV6_ADDR_ANY) 1137 addr6 = &ipv6_hdr(skb)->daddr; 1138 1139 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1140 neigh_release(neigh); 1141 } else if (payload_protocol == htons(ETH_P_IP)) { 1142 const struct rtable *rt = skb_rtable(skb); 1143 1144 if (!rt) 1145 goto tx_err_link_failure; 1146 1147 if (rt->rt_gw_family == AF_INET6) 1148 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr)); 1149 } 1150 } else if (t->parms.proto != 0 && !(t->parms.flags & 1151 (IP6_TNL_F_USE_ORIG_TCLASS | 1152 IP6_TNL_F_USE_ORIG_FWMARK))) { 1153 /* enable the cache only if neither the outer protocol nor the 1154 * routing decision depends on the current inner header value 1155 */ 1156 use_cache = true; 1157 } 1158 1159 if (use_cache) 1160 dst = dst_cache_get(&t->dst_cache); 1161 1162 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1163 goto tx_err_link_failure; 1164 1165 if (!dst) { 1166 route_lookup: 1167 /* add dsfield to flowlabel for route lookup */ 1168 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1169 1170 dst = ip6_route_output(net, NULL, fl6); 1171 1172 if (dst->error) 1173 goto tx_err_link_failure; 1174 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1175 if (IS_ERR(dst)) { 1176 err = PTR_ERR(dst); 1177 dst = NULL; 1178 goto tx_err_link_failure; 1179 } 1180 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1181 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1182 &fl6->daddr, 0, &fl6->saddr)) 1183 goto tx_err_link_failure; 1184 ndst = dst; 1185 } 1186 1187 tdev = dst_dev(dst); 1188 1189 if (tdev == dev) { 1190 DEV_STATS_INC(dev, collisions); 1191 net_warn_ratelimited("%s: Local routing loop detected!\n", 1192 t->parms.name); 1193 goto tx_err_dst_release; 1194 } 1195 mtu = dst6_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1196 if (encap_limit >= 0) { 1197 max_headroom += 8; 1198 mtu -= 8; 1199 } 1200 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1201 IPV6_MIN_MTU : IPV4_MIN_MTU); 1202 1203 skb_dst_update_pmtu_no_confirm(skb, mtu); 1204 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1205 *pmtu = mtu; 1206 err = -EMSGSIZE; 1207 goto tx_err_dst_release; 1208 } 1209 1210 if (t->err_count > 0) { 1211 if (time_before(jiffies, 1212 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1213 t->err_count--; 1214 1215 dst_link_failure(skb); 1216 } else { 1217 t->err_count = 0; 1218 } 1219 } 1220 1221 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1222 1223 /* 1224 * Okay, now see if we can stuff it in the buffer as-is. 1225 */ 1226 max_headroom += LL_RESERVED_SPACE(tdev); 1227 1228 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1229 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1230 struct sk_buff *new_skb; 1231 1232 new_skb = skb_realloc_headroom(skb, max_headroom); 1233 if (!new_skb) 1234 goto tx_err_dst_release; 1235 1236 if (skb->sk) 1237 skb_set_owner_w(new_skb, skb->sk); 1238 consume_skb(skb); 1239 skb = new_skb; 1240 } 1241 1242 if (t->parms.collect_md) { 1243 if (t->encap.type != TUNNEL_ENCAP_NONE) 1244 goto tx_err_dst_release; 1245 } else { 1246 if (use_cache && ndst) 1247 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1248 } 1249 skb_dst_set(skb, dst); 1250 1251 if (hop_limit == 0) { 1252 if (payload_protocol == htons(ETH_P_IP)) 1253 hop_limit = ip_hdr(skb)->ttl; 1254 else if (payload_protocol == htons(ETH_P_IPV6)) 1255 hop_limit = ipv6_hdr(skb)->hop_limit; 1256 else 1257 hop_limit = ip6_dst_hoplimit(dst); 1258 } 1259 1260 /* Calculate max headroom for all the headers and adjust 1261 * needed_headroom if necessary. 1262 */ 1263 max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct ipv6hdr) 1264 + dst->header_len + t->hlen; 1265 ip_tunnel_adj_headroom(dev, max_headroom); 1266 1267 err = ip6_tnl_encap(skb, t, &proto, fl6); 1268 if (err) 1269 return err; 1270 1271 if (encap_limit >= 0) { 1272 init_tel_txopt(&opt, encap_limit); 1273 proto = ipv6_push_frag_opts(skb, &opt.ops, proto); 1274 } 1275 1276 skb_push(skb, sizeof(struct ipv6hdr)); 1277 skb_reset_network_header(skb); 1278 ipv6h = ipv6_hdr(skb); 1279 ip6_flow_hdr(ipv6h, dsfield, 1280 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1281 ipv6h->hop_limit = hop_limit; 1282 ipv6h->nexthdr = proto; 1283 ipv6h->saddr = fl6->saddr; 1284 ipv6h->daddr = fl6->daddr; 1285 ip6tunnel_xmit(NULL, skb, dev, 0); 1286 return 0; 1287 tx_err_link_failure: 1288 DEV_STATS_INC(dev, tx_carrier_errors); 1289 dst_link_failure(skb); 1290 tx_err_dst_release: 1291 dst_release(dst); 1292 return err; 1293 } 1294 EXPORT_SYMBOL(ip6_tnl_xmit); 1295 1296 static inline int 1297 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, 1298 u8 protocol) 1299 { 1300 struct ip6_tnl *t = netdev_priv(dev); 1301 struct ipv6hdr *ipv6h; 1302 const struct iphdr *iph; 1303 int encap_limit = -1; 1304 __u16 offset; 1305 struct flowi6 fl6; 1306 __u8 dsfield, orig_dsfield; 1307 __u32 mtu; 1308 u8 tproto; 1309 int err; 1310 1311 tproto = READ_ONCE(t->parms.proto); 1312 if (tproto != protocol && tproto != 0) 1313 return -1; 1314 1315 if (t->parms.collect_md) { 1316 struct ip_tunnel_info *tun_info; 1317 const struct ip_tunnel_key *key; 1318 1319 tun_info = skb_tunnel_info(skb); 1320 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1321 ip_tunnel_info_af(tun_info) != AF_INET6)) 1322 return -1; 1323 key = &tun_info->key; 1324 memset(&fl6, 0, sizeof(fl6)); 1325 fl6.flowi6_proto = protocol; 1326 fl6.saddr = key->u.ipv6.src; 1327 fl6.daddr = key->u.ipv6.dst; 1328 fl6.flowlabel = key->label; 1329 dsfield = key->tos; 1330 switch (protocol) { 1331 case IPPROTO_IPIP: 1332 iph = ip_hdr(skb); 1333 orig_dsfield = ipv4_get_dsfield(iph); 1334 break; 1335 case IPPROTO_IPV6: 1336 ipv6h = ipv6_hdr(skb); 1337 orig_dsfield = ipv6_get_dsfield(ipv6h); 1338 break; 1339 default: 1340 orig_dsfield = dsfield; 1341 break; 1342 } 1343 } else { 1344 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1345 encap_limit = t->parms.encap_limit; 1346 if (protocol == IPPROTO_IPV6) { 1347 offset = ip6_tnl_parse_tlv_enc_lim(skb, 1348 skb_network_header(skb)); 1349 /* ip6_tnl_parse_tlv_enc_lim() might have 1350 * reallocated skb->head 1351 */ 1352 if (offset > 0) { 1353 struct ipv6_tlv_tnl_enc_lim *tel; 1354 1355 tel = (void *)&skb_network_header(skb)[offset]; 1356 if (tel->encap_limit == 0) { 1357 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB, 1358 ICMPV6_HDR_FIELD, offset + 2); 1359 return -1; 1360 } 1361 encap_limit = tel->encap_limit - 1; 1362 } 1363 } 1364 1365 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1366 fl6.flowi6_proto = protocol; 1367 1368 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1369 fl6.flowi6_mark = skb->mark; 1370 else 1371 fl6.flowi6_mark = t->parms.fwmark; 1372 switch (protocol) { 1373 case IPPROTO_IPIP: 1374 iph = ip_hdr(skb); 1375 orig_dsfield = ipv4_get_dsfield(iph); 1376 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1377 dsfield = orig_dsfield; 1378 else 1379 dsfield = ip6_tclass(t->parms.flowinfo); 1380 break; 1381 case IPPROTO_IPV6: 1382 ipv6h = ipv6_hdr(skb); 1383 orig_dsfield = ipv6_get_dsfield(ipv6h); 1384 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1385 dsfield = orig_dsfield; 1386 else 1387 dsfield = ip6_tclass(t->parms.flowinfo); 1388 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1389 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1390 break; 1391 default: 1392 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo); 1393 break; 1394 } 1395 } 1396 1397 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1398 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield); 1399 1400 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1401 return -1; 1402 1403 skb_set_inner_ipproto(skb, protocol); 1404 1405 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1406 protocol); 1407 if (err != 0) { 1408 /* XXX: send ICMP error even if DF is not set. */ 1409 if (err == -EMSGSIZE) 1410 switch (protocol) { 1411 case IPPROTO_IPIP: 1412 icmp_ndo_send(skb, ICMP_DEST_UNREACH, 1413 ICMP_FRAG_NEEDED, htonl(mtu)); 1414 break; 1415 case IPPROTO_IPV6: 1416 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1417 break; 1418 default: 1419 break; 1420 } 1421 return -1; 1422 } 1423 1424 return 0; 1425 } 1426 1427 static netdev_tx_t 1428 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1429 { 1430 struct ip6_tnl *t = netdev_priv(dev); 1431 u8 ipproto; 1432 int ret; 1433 1434 if (!pskb_inet_may_pull(skb)) 1435 goto tx_err; 1436 1437 switch (skb->protocol) { 1438 case htons(ETH_P_IP): 1439 ipproto = IPPROTO_IPIP; 1440 break; 1441 case htons(ETH_P_IPV6): 1442 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb))) 1443 goto tx_err; 1444 ipproto = IPPROTO_IPV6; 1445 break; 1446 case htons(ETH_P_MPLS_UC): 1447 ipproto = IPPROTO_MPLS; 1448 break; 1449 default: 1450 goto tx_err; 1451 } 1452 1453 ret = ipxip6_tnl_xmit(skb, dev, ipproto); 1454 if (ret < 0) 1455 goto tx_err; 1456 1457 return NETDEV_TX_OK; 1458 1459 tx_err: 1460 DEV_STATS_INC(dev, tx_errors); 1461 DEV_STATS_INC(dev, tx_dropped); 1462 kfree_skb(skb); 1463 return NETDEV_TX_OK; 1464 } 1465 1466 static void ip6_tnl_link_config(struct ip6_tnl *t) 1467 { 1468 struct net_device *dev = t->dev; 1469 struct net_device *tdev = NULL; 1470 struct __ip6_tnl_parm *p = &t->parms; 1471 struct flowi6 *fl6 = &t->fl.u.ip6; 1472 int t_hlen; 1473 int mtu; 1474 1475 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr)); 1476 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1477 1478 /* Set up flowi template */ 1479 fl6->saddr = p->laddr; 1480 fl6->daddr = p->raddr; 1481 fl6->flowi6_oif = p->link; 1482 fl6->flowlabel = 0; 1483 1484 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1485 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1486 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1487 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1488 1489 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1490 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1491 1492 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1493 dev->flags |= IFF_POINTOPOINT; 1494 else 1495 dev->flags &= ~IFF_POINTOPOINT; 1496 1497 t->tun_hlen = 0; 1498 t->hlen = t->encap_hlen + t->tun_hlen; 1499 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1500 1501 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1502 int strict = (ipv6_addr_type(&p->raddr) & 1503 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1504 1505 struct rt6_info *rt = rt6_lookup(t->net, 1506 &p->raddr, &p->laddr, 1507 p->link, NULL, strict); 1508 if (rt) { 1509 tdev = rt->dst.dev; 1510 ip6_rt_put(rt); 1511 } 1512 1513 if (!tdev && p->link) 1514 tdev = __dev_get_by_index(t->net, p->link); 1515 1516 if (tdev) { 1517 dev->needed_headroom = tdev->hard_header_len + 1518 tdev->needed_headroom + t_hlen; 1519 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU); 1520 1521 mtu = mtu - t_hlen; 1522 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1523 mtu -= 8; 1524 1525 if (mtu < IPV6_MIN_MTU) 1526 mtu = IPV6_MIN_MTU; 1527 WRITE_ONCE(dev->mtu, mtu); 1528 } 1529 } 1530 } 1531 1532 /** 1533 * ip6_tnl_change - update the tunnel parameters 1534 * @t: tunnel to be changed 1535 * @p: tunnel configuration parameters 1536 * 1537 * Description: 1538 * ip6_tnl_change() updates the tunnel parameters 1539 **/ 1540 1541 static void 1542 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1543 { 1544 t->parms.laddr = p->laddr; 1545 t->parms.raddr = p->raddr; 1546 t->parms.flags = p->flags; 1547 t->parms.hop_limit = p->hop_limit; 1548 t->parms.encap_limit = p->encap_limit; 1549 t->parms.flowinfo = p->flowinfo; 1550 t->parms.link = p->link; 1551 t->parms.proto = p->proto; 1552 t->parms.fwmark = p->fwmark; 1553 dst_cache_reset(&t->dst_cache); 1554 ip6_tnl_link_config(t); 1555 } 1556 1557 static void ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1558 { 1559 struct net *net = t->net; 1560 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1561 1562 ip6_tnl_unlink(ip6n, t); 1563 synchronize_net(); 1564 ip6_tnl_change(t, p); 1565 ip6_tnl_link(ip6n, t); 1566 netdev_state_change(t->dev); 1567 } 1568 1569 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p, 1570 bool strict) 1571 { 1572 /* For the default ip6tnl0 device, allow changing only the protocol 1573 * (the IP6_TNL_F_CAP_PER_PACKET flag is set on ip6tnl0, and all other 1574 * parameters are 0). 1575 */ 1576 if (strict && 1577 (!ipv6_addr_any(&p->laddr) || !ipv6_addr_any(&p->raddr) || 1578 p->flags != t->parms.flags || p->hop_limit || p->encap_limit || 1579 p->flowinfo || p->link || p->fwmark || p->collect_md)) 1580 return -EINVAL; 1581 1582 t->parms.proto = p->proto; 1583 netdev_state_change(t->dev); 1584 return 0; 1585 } 1586 1587 static void 1588 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1589 { 1590 p->laddr = u->laddr; 1591 p->raddr = u->raddr; 1592 p->flags = u->flags; 1593 p->hop_limit = u->hop_limit; 1594 p->encap_limit = u->encap_limit; 1595 p->flowinfo = u->flowinfo; 1596 p->link = u->link; 1597 p->proto = u->proto; 1598 memcpy(p->name, u->name, sizeof(u->name)); 1599 } 1600 1601 static void 1602 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1603 { 1604 u->laddr = p->laddr; 1605 u->raddr = p->raddr; 1606 u->flags = p->flags; 1607 u->hop_limit = p->hop_limit; 1608 u->encap_limit = p->encap_limit; 1609 u->flowinfo = p->flowinfo; 1610 u->link = p->link; 1611 u->proto = p->proto; 1612 memcpy(u->name, p->name, sizeof(u->name)); 1613 } 1614 1615 /** 1616 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace 1617 * @dev: virtual device associated with tunnel 1618 * @ifr: unused 1619 * @data: parameters passed from userspace 1620 * @cmd: command to be performed 1621 * 1622 * Description: 1623 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1624 * from userspace. 1625 * 1626 * The possible commands are the following: 1627 * %SIOCGETTUNNEL: get tunnel parameters for device 1628 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1629 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1630 * %SIOCDELTUNNEL: delete tunnel 1631 * 1632 * The fallback device "ip6tnl0", created during module 1633 * initialization, can be used for creating other tunnel devices. 1634 * 1635 * Return: 1636 * 0 on success, 1637 * %-EFAULT if unable to copy data to or from userspace, 1638 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1639 * %-EINVAL if passed tunnel parameters are invalid, 1640 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1641 * %-ENODEV if attempting to change or delete a nonexisting device 1642 **/ 1643 1644 static int 1645 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 1646 void __user *data, int cmd) 1647 { 1648 int err = 0; 1649 struct ip6_tnl_parm p; 1650 struct __ip6_tnl_parm p1; 1651 struct ip6_tnl *t = netdev_priv(dev); 1652 struct net *net = t->net; 1653 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1654 1655 memset(&p1, 0, sizeof(p1)); 1656 1657 switch (cmd) { 1658 case SIOCGETTUNNEL: 1659 if (dev == ip6n->fb_tnl_dev) { 1660 if (copy_from_user(&p, data, sizeof(p))) { 1661 err = -EFAULT; 1662 break; 1663 } 1664 ip6_tnl_parm_from_user(&p1, &p); 1665 t = ip6_tnl_locate(net, &p1, 0); 1666 if (IS_ERR(t)) 1667 t = netdev_priv(dev); 1668 } else { 1669 memset(&p, 0, sizeof(p)); 1670 } 1671 ip6_tnl_parm_to_user(&p, &t->parms); 1672 if (copy_to_user(data, &p, sizeof(p))) 1673 err = -EFAULT; 1674 break; 1675 case SIOCADDTUNNEL: 1676 case SIOCCHGTUNNEL: 1677 err = -EPERM; 1678 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1679 break; 1680 err = -EFAULT; 1681 if (copy_from_user(&p, data, sizeof(p))) 1682 break; 1683 err = -EINVAL; 1684 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1685 p.proto != 0) 1686 break; 1687 ip6_tnl_parm_from_user(&p1, &p); 1688 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1689 if (cmd == SIOCCHGTUNNEL) { 1690 if (!IS_ERR(t)) { 1691 if (t->dev != dev) { 1692 err = -EEXIST; 1693 break; 1694 } 1695 } else 1696 t = netdev_priv(dev); 1697 if (dev == ip6n->fb_tnl_dev) 1698 ip6_tnl0_update(t, &p1, false); 1699 else 1700 ip6_tnl_update(t, &p1); 1701 } 1702 if (!IS_ERR(t)) { 1703 err = 0; 1704 ip6_tnl_parm_to_user(&p, &t->parms); 1705 if (copy_to_user(data, &p, sizeof(p))) 1706 err = -EFAULT; 1707 1708 } else { 1709 err = PTR_ERR(t); 1710 } 1711 break; 1712 case SIOCDELTUNNEL: 1713 err = -EPERM; 1714 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1715 break; 1716 1717 if (dev == ip6n->fb_tnl_dev) { 1718 err = -EFAULT; 1719 if (copy_from_user(&p, data, sizeof(p))) 1720 break; 1721 err = -ENOENT; 1722 ip6_tnl_parm_from_user(&p1, &p); 1723 t = ip6_tnl_locate(net, &p1, 0); 1724 if (IS_ERR(t)) 1725 break; 1726 err = -EPERM; 1727 if (t->dev == ip6n->fb_tnl_dev) 1728 break; 1729 dev = t->dev; 1730 } 1731 err = 0; 1732 unregister_netdevice(dev); 1733 break; 1734 default: 1735 err = -EINVAL; 1736 } 1737 return err; 1738 } 1739 1740 /** 1741 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1742 * @dev: virtual device associated with tunnel 1743 * @new_mtu: the new mtu 1744 * 1745 * Return: 1746 * 0 on success, 1747 * %-EINVAL if mtu too small 1748 **/ 1749 1750 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1751 { 1752 struct ip6_tnl *tnl = netdev_priv(dev); 1753 int t_hlen; 1754 1755 t_hlen = tnl->hlen + sizeof(struct ipv6hdr); 1756 if (tnl->parms.proto == IPPROTO_IPV6) { 1757 if (new_mtu < IPV6_MIN_MTU) 1758 return -EINVAL; 1759 } else { 1760 if (new_mtu < ETH_MIN_MTU) 1761 return -EINVAL; 1762 } 1763 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1764 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len - t_hlen) 1765 return -EINVAL; 1766 } else { 1767 if (new_mtu > IP_MAX_MTU - dev->hard_header_len - t_hlen) 1768 return -EINVAL; 1769 } 1770 WRITE_ONCE(dev->mtu, new_mtu); 1771 return 0; 1772 } 1773 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1774 1775 int ip6_tnl_get_iflink(const struct net_device *dev) 1776 { 1777 struct ip6_tnl *t = netdev_priv(dev); 1778 1779 return READ_ONCE(t->parms.link); 1780 } 1781 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1782 1783 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1784 unsigned int num) 1785 { 1786 if (num >= MAX_IPTUN_ENCAP_OPS) 1787 return -ERANGE; 1788 1789 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1790 &ip6tun_encaps[num], 1791 NULL, ops) ? 0 : -1; 1792 } 1793 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1794 1795 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1796 unsigned int num) 1797 { 1798 int ret; 1799 1800 if (num >= MAX_IPTUN_ENCAP_OPS) 1801 return -ERANGE; 1802 1803 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1804 &ip6tun_encaps[num], 1805 ops, NULL) == ops) ? 0 : -1; 1806 1807 synchronize_net(); 1808 1809 return ret; 1810 } 1811 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1812 1813 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1814 struct ip_tunnel_encap *ipencap) 1815 { 1816 int hlen; 1817 1818 memset(&t->encap, 0, sizeof(t->encap)); 1819 1820 hlen = ip6_encap_hlen(ipencap); 1821 if (hlen < 0) 1822 return hlen; 1823 1824 t->encap.type = ipencap->type; 1825 t->encap.sport = ipencap->sport; 1826 t->encap.dport = ipencap->dport; 1827 t->encap.flags = ipencap->flags; 1828 1829 t->encap_hlen = hlen; 1830 t->hlen = t->encap_hlen + t->tun_hlen; 1831 1832 return 0; 1833 } 1834 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1835 1836 static int ip6_tnl_fill_forward_path(struct net_device_path_ctx *ctx, 1837 struct net_device_path *path) 1838 { 1839 struct ip6_tnl *t = netdev_priv(ctx->dev); 1840 struct flowi6 fl6 = { 1841 .daddr = t->parms.raddr, 1842 }; 1843 struct dst_entry *dst; 1844 int err; 1845 1846 dst = ip6_route_output(dev_net(ctx->dev), NULL, &fl6); 1847 if (!dst->error) { 1848 path->type = DEV_PATH_TUN; 1849 path->tun.src_v6 = t->parms.laddr; 1850 path->tun.dst_v6 = t->parms.raddr; 1851 path->tun.l3_proto = IPPROTO_IPV6; 1852 path->dev = ctx->dev; 1853 ctx->dev = dst->dev; 1854 } 1855 1856 err = dst->error; 1857 dst_release(dst); 1858 1859 return err; 1860 } 1861 1862 static const struct net_device_ops ip6_tnl_netdev_ops = { 1863 .ndo_init = ip6_tnl_dev_init, 1864 .ndo_uninit = ip6_tnl_dev_uninit, 1865 .ndo_start_xmit = ip6_tnl_start_xmit, 1866 .ndo_siocdevprivate = ip6_tnl_siocdevprivate, 1867 .ndo_change_mtu = ip6_tnl_change_mtu, 1868 .ndo_get_stats64 = dev_get_tstats64, 1869 .ndo_get_iflink = ip6_tnl_get_iflink, 1870 .ndo_fill_forward_path = ip6_tnl_fill_forward_path, 1871 }; 1872 1873 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1874 NETIF_F_FRAGLIST | \ 1875 NETIF_F_HIGHDMA | \ 1876 NETIF_F_GSO_SOFTWARE | \ 1877 NETIF_F_HW_CSUM) 1878 1879 /** 1880 * ip6_tnl_dev_setup - setup virtual tunnel device 1881 * @dev: virtual device associated with tunnel 1882 * 1883 * Description: 1884 * Initialize function pointers and device parameters 1885 **/ 1886 1887 static void ip6_tnl_dev_setup(struct net_device *dev) 1888 { 1889 dev->netdev_ops = &ip6_tnl_netdev_ops; 1890 dev->header_ops = &ip_tunnel_header_ops; 1891 dev->needs_free_netdev = true; 1892 dev->priv_destructor = ip6_dev_free; 1893 1894 dev->type = ARPHRD_TUNNEL6; 1895 dev->flags |= IFF_NOARP; 1896 dev->addr_len = sizeof(struct in6_addr); 1897 dev->lltx = true; 1898 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; 1899 netif_keep_dst(dev); 1900 1901 dev->features |= IPXIPX_FEATURES; 1902 dev->hw_features |= IPXIPX_FEATURES; 1903 1904 /* This perm addr will be used as interface identifier by IPv6 */ 1905 dev->addr_assign_type = NET_ADDR_RANDOM; 1906 eth_random_addr(dev->perm_addr); 1907 } 1908 1909 1910 /** 1911 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1912 * @dev: virtual device associated with tunnel 1913 **/ 1914 1915 static inline int 1916 ip6_tnl_dev_init_gen(struct net_device *dev) 1917 { 1918 struct ip6_tnl *t = netdev_priv(dev); 1919 int ret; 1920 int t_hlen; 1921 1922 t->dev = dev; 1923 1924 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1925 if (ret) 1926 return ret; 1927 1928 ret = gro_cells_init(&t->gro_cells, dev); 1929 if (ret) 1930 goto destroy_dst; 1931 1932 t->tun_hlen = 0; 1933 t->hlen = t->encap_hlen + t->tun_hlen; 1934 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1935 1936 dev->type = ARPHRD_TUNNEL6; 1937 dev->mtu = ETH_DATA_LEN - t_hlen; 1938 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1939 dev->mtu -= 8; 1940 dev->min_mtu = ETH_MIN_MTU; 1941 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len - t_hlen; 1942 1943 netdev_hold(dev, &t->dev_tracker, GFP_KERNEL); 1944 netdev_lockdep_set_classes(dev); 1945 return 0; 1946 1947 destroy_dst: 1948 dst_cache_destroy(&t->dst_cache); 1949 1950 return ret; 1951 } 1952 1953 /** 1954 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1955 * @dev: virtual device associated with tunnel 1956 **/ 1957 1958 static int ip6_tnl_dev_init(struct net_device *dev) 1959 { 1960 struct ip6_tnl *t = netdev_priv(dev); 1961 int err = ip6_tnl_dev_init_gen(dev); 1962 1963 if (err) 1964 return err; 1965 ip6_tnl_link_config(t); 1966 if (t->parms.collect_md) 1967 netif_keep_dst(dev); 1968 return 0; 1969 } 1970 1971 /** 1972 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1973 * @dev: fallback device 1974 * 1975 * Return: 0 1976 **/ 1977 1978 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1979 { 1980 struct ip6_tnl *t = netdev_priv(dev); 1981 struct net *net = dev_net(dev); 1982 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1983 1984 t->net = net; 1985 t->parms.proto = IPPROTO_IPV6; 1986 1987 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1988 return 0; 1989 } 1990 1991 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1992 struct netlink_ext_ack *extack) 1993 { 1994 u8 proto; 1995 1996 if (!data || !data[IFLA_IPTUN_PROTO]) 1997 return 0; 1998 1999 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 2000 if (proto != IPPROTO_IPV6 && 2001 proto != IPPROTO_IPIP && 2002 proto != 0) 2003 return -EINVAL; 2004 2005 return 0; 2006 } 2007 2008 static void ip6_tnl_netlink_parms(struct nlattr *data[], 2009 struct __ip6_tnl_parm *parms) 2010 { 2011 memset(parms, 0, sizeof(*parms)); 2012 2013 if (!data) 2014 return; 2015 2016 if (data[IFLA_IPTUN_LINK]) 2017 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 2018 2019 if (data[IFLA_IPTUN_LOCAL]) 2020 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 2021 2022 if (data[IFLA_IPTUN_REMOTE]) 2023 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 2024 2025 if (data[IFLA_IPTUN_TTL]) 2026 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 2027 2028 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 2029 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 2030 2031 if (data[IFLA_IPTUN_FLOWINFO]) 2032 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 2033 2034 if (data[IFLA_IPTUN_FLAGS]) 2035 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 2036 2037 if (data[IFLA_IPTUN_PROTO]) 2038 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 2039 2040 if (data[IFLA_IPTUN_COLLECT_METADATA]) 2041 parms->collect_md = true; 2042 2043 if (data[IFLA_IPTUN_FWMARK]) 2044 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 2045 } 2046 2047 static int ip6_tnl_newlink(struct net_device *dev, 2048 struct rtnl_newlink_params *params, 2049 struct netlink_ext_ack *extack) 2050 { 2051 struct nlattr **data = params->data; 2052 struct nlattr **tb = params->tb; 2053 struct ip_tunnel_encap ipencap; 2054 struct ip6_tnl_net *ip6n; 2055 struct ip6_tnl *nt, *t; 2056 struct net *net; 2057 int err; 2058 2059 net = params->link_net ? : dev_net(dev); 2060 ip6n = net_generic(net, ip6_tnl_net_id); 2061 nt = netdev_priv(dev); 2062 nt->net = net; 2063 2064 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2065 err = ip6_tnl_encap_setup(nt, &ipencap); 2066 if (err < 0) 2067 return err; 2068 } 2069 2070 ip6_tnl_netlink_parms(data, &nt->parms); 2071 2072 if (nt->parms.collect_md) { 2073 if (rtnl_dereference(ip6n->collect_md_tun)) 2074 return -EEXIST; 2075 } else { 2076 t = ip6_tnl_locate(net, &nt->parms, 0); 2077 if (!IS_ERR(t)) 2078 return -EEXIST; 2079 } 2080 2081 err = ip6_tnl_create2(dev); 2082 if (!err && tb[IFLA_MTU]) 2083 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2084 2085 return err; 2086 } 2087 2088 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2089 struct nlattr *data[], 2090 struct netlink_ext_ack *extack) 2091 { 2092 struct ip6_tnl *t = netdev_priv(dev); 2093 struct __ip6_tnl_parm p; 2094 struct net *net = t->net; 2095 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2096 struct ip_tunnel_encap ipencap; 2097 2098 if (dev == ip6n->fb_tnl_dev) { 2099 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2100 /* iproute2 always sets TUNNEL_ENCAP_FLAG_CSUM6, so 2101 * let's ignore this flag. 2102 */ 2103 ipencap.flags &= ~TUNNEL_ENCAP_FLAG_CSUM6; 2104 if (memchr_inv(&ipencap, 0, sizeof(ipencap))) { 2105 NL_SET_ERR_MSG(extack, 2106 "Only protocol can be changed for fallback tunnel, not encap params"); 2107 return -EINVAL; 2108 } 2109 } 2110 2111 ip6_tnl_netlink_parms(data, &p); 2112 if (ip6_tnl0_update(t, &p, true) < 0) { 2113 NL_SET_ERR_MSG(extack, 2114 "Only protocol can be changed for fallback tunnel"); 2115 return -EINVAL; 2116 } 2117 2118 return 0; 2119 } 2120 2121 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 2122 int err = ip6_tnl_encap_setup(t, &ipencap); 2123 2124 if (err < 0) 2125 return err; 2126 } 2127 ip6_tnl_netlink_parms(data, &p); 2128 if (p.collect_md) 2129 return -EINVAL; 2130 2131 t = ip6_tnl_locate(net, &p, 0); 2132 if (!IS_ERR(t)) { 2133 if (t->dev != dev) 2134 return -EEXIST; 2135 } else 2136 t = netdev_priv(dev); 2137 2138 ip6_tnl_update(t, &p); 2139 return 0; 2140 } 2141 2142 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2143 { 2144 struct net *net = dev_net(dev); 2145 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2146 2147 if (dev != ip6n->fb_tnl_dev) 2148 unregister_netdevice_queue(dev, head); 2149 } 2150 2151 static size_t ip6_tnl_get_size(const struct net_device *dev) 2152 { 2153 return 2154 /* IFLA_IPTUN_LINK */ 2155 nla_total_size(4) + 2156 /* IFLA_IPTUN_LOCAL */ 2157 nla_total_size(sizeof(struct in6_addr)) + 2158 /* IFLA_IPTUN_REMOTE */ 2159 nla_total_size(sizeof(struct in6_addr)) + 2160 /* IFLA_IPTUN_TTL */ 2161 nla_total_size(1) + 2162 /* IFLA_IPTUN_ENCAP_LIMIT */ 2163 nla_total_size(1) + 2164 /* IFLA_IPTUN_FLOWINFO */ 2165 nla_total_size(4) + 2166 /* IFLA_IPTUN_FLAGS */ 2167 nla_total_size(4) + 2168 /* IFLA_IPTUN_PROTO */ 2169 nla_total_size(1) + 2170 /* IFLA_IPTUN_ENCAP_TYPE */ 2171 nla_total_size(2) + 2172 /* IFLA_IPTUN_ENCAP_FLAGS */ 2173 nla_total_size(2) + 2174 /* IFLA_IPTUN_ENCAP_SPORT */ 2175 nla_total_size(2) + 2176 /* IFLA_IPTUN_ENCAP_DPORT */ 2177 nla_total_size(2) + 2178 /* IFLA_IPTUN_COLLECT_METADATA */ 2179 nla_total_size(0) + 2180 /* IFLA_IPTUN_FWMARK */ 2181 nla_total_size(4) + 2182 0; 2183 } 2184 2185 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2186 { 2187 struct ip6_tnl *tunnel = netdev_priv(dev); 2188 struct __ip6_tnl_parm *parm = &tunnel->parms; 2189 2190 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2191 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2192 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2193 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2194 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2195 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2196 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2197 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2198 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2199 goto nla_put_failure; 2200 2201 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2202 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2203 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2204 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2205 goto nla_put_failure; 2206 2207 if (parm->collect_md) 2208 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2209 goto nla_put_failure; 2210 2211 return 0; 2212 2213 nla_put_failure: 2214 return -EMSGSIZE; 2215 } 2216 2217 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2218 { 2219 struct ip6_tnl *tunnel = netdev_priv(dev); 2220 2221 return READ_ONCE(tunnel->net); 2222 } 2223 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2224 2225 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2226 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2227 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2228 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2229 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2230 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2231 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2232 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2233 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2234 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2235 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2236 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2237 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2238 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2239 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2240 }; 2241 2242 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2243 .kind = "ip6tnl", 2244 .maxtype = IFLA_IPTUN_MAX, 2245 .policy = ip6_tnl_policy, 2246 .priv_size = sizeof(struct ip6_tnl), 2247 .setup = ip6_tnl_dev_setup, 2248 .validate = ip6_tnl_validate, 2249 .newlink = ip6_tnl_newlink, 2250 .changelink = ip6_tnl_changelink, 2251 .dellink = ip6_tnl_dellink, 2252 .get_size = ip6_tnl_get_size, 2253 .fill_info = ip6_tnl_fill_info, 2254 .get_link_net = ip6_tnl_get_link_net, 2255 }; 2256 2257 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2258 .handler = ip4ip6_rcv, 2259 .err_handler = ip4ip6_err, 2260 .priority = 1, 2261 }; 2262 2263 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2264 .handler = ip6ip6_rcv, 2265 .err_handler = ip6ip6_err, 2266 .priority = 1, 2267 }; 2268 2269 static struct xfrm6_tunnel mplsip6_handler __read_mostly = { 2270 .handler = mplsip6_rcv, 2271 .err_handler = mplsip6_err, 2272 .priority = 1, 2273 }; 2274 2275 static void __net_exit ip6_tnl_exit_rtnl_net(struct net *net, struct list_head *list) 2276 { 2277 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2278 struct net_device *dev, *aux; 2279 int h; 2280 struct ip6_tnl *t; 2281 2282 for_each_netdev_safe(net, dev, aux) 2283 if (dev->rtnl_link_ops == &ip6_link_ops) 2284 unregister_netdevice_queue(dev, list); 2285 2286 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2287 t = rtnl_net_dereference(net, ip6n->tnls_r_l[h]); 2288 while (t) { 2289 /* If dev is in the same netns, it has already 2290 * been added to the list by the previous loop. 2291 */ 2292 if (!net_eq(dev_net(t->dev), net)) 2293 unregister_netdevice_queue(t->dev, list); 2294 2295 t = rtnl_net_dereference(net, t->next); 2296 } 2297 } 2298 2299 t = rtnl_net_dereference(net, ip6n->tnls_wc[0]); 2300 while (t) { 2301 /* If dev is in the same netns, it has already 2302 * been added to the list by the previous loop. 2303 */ 2304 if (!net_eq(dev_net(t->dev), net)) 2305 unregister_netdevice_queue(t->dev, list); 2306 2307 t = rtnl_net_dereference(net, t->next); 2308 } 2309 } 2310 2311 static int __net_init ip6_tnl_init_net(struct net *net) 2312 { 2313 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2314 struct ip6_tnl *t = NULL; 2315 int err; 2316 2317 ip6n->tnls[0] = ip6n->tnls_wc; 2318 ip6n->tnls[1] = ip6n->tnls_r_l; 2319 2320 if (!net_has_fallback_tunnels(net)) 2321 return 0; 2322 err = -ENOMEM; 2323 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2324 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2325 2326 if (!ip6n->fb_tnl_dev) 2327 goto err_alloc_dev; 2328 dev_net_set(ip6n->fb_tnl_dev, net); 2329 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2330 /* FB netdevice is special: we have one, and only one per netns. 2331 * Allowing to move it to another netns is clearly unsafe. 2332 */ 2333 ip6n->fb_tnl_dev->netns_immutable = true; 2334 2335 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2336 if (err < 0) 2337 goto err_register; 2338 2339 err = register_netdev(ip6n->fb_tnl_dev); 2340 if (err < 0) 2341 goto err_register; 2342 2343 t = netdev_priv(ip6n->fb_tnl_dev); 2344 2345 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2346 return 0; 2347 2348 err_register: 2349 free_netdev(ip6n->fb_tnl_dev); 2350 err_alloc_dev: 2351 return err; 2352 } 2353 2354 static struct pernet_operations ip6_tnl_net_ops = { 2355 .init = ip6_tnl_init_net, 2356 .exit_rtnl = ip6_tnl_exit_rtnl_net, 2357 .id = &ip6_tnl_net_id, 2358 .size = sizeof(struct ip6_tnl_net), 2359 }; 2360 2361 /** 2362 * ip6_tunnel_init - register protocol and reserve needed resources 2363 * 2364 * Return: 0 on success 2365 **/ 2366 2367 static int __init ip6_tunnel_init(void) 2368 { 2369 int err; 2370 2371 if (!ipv6_mod_enabled()) 2372 return -EOPNOTSUPP; 2373 2374 err = register_pernet_device(&ip6_tnl_net_ops); 2375 if (err < 0) 2376 goto out_pernet; 2377 2378 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2379 if (err < 0) { 2380 pr_err("%s: can't register ip4ip6\n", __func__); 2381 goto out_ip4ip6; 2382 } 2383 2384 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2385 if (err < 0) { 2386 pr_err("%s: can't register ip6ip6\n", __func__); 2387 goto out_ip6ip6; 2388 } 2389 2390 if (ip6_tnl_mpls_supported()) { 2391 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS); 2392 if (err < 0) { 2393 pr_err("%s: can't register mplsip6\n", __func__); 2394 goto out_mplsip6; 2395 } 2396 } 2397 2398 err = rtnl_link_register(&ip6_link_ops); 2399 if (err < 0) 2400 goto rtnl_link_failed; 2401 2402 return 0; 2403 2404 rtnl_link_failed: 2405 if (ip6_tnl_mpls_supported()) 2406 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS); 2407 out_mplsip6: 2408 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2409 out_ip6ip6: 2410 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2411 out_ip4ip6: 2412 unregister_pernet_device(&ip6_tnl_net_ops); 2413 out_pernet: 2414 return err; 2415 } 2416 2417 /** 2418 * ip6_tunnel_cleanup - free resources and unregister protocol 2419 **/ 2420 2421 static void __exit ip6_tunnel_cleanup(void) 2422 { 2423 rtnl_link_unregister(&ip6_link_ops); 2424 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2425 pr_info("%s: can't deregister ip4ip6\n", __func__); 2426 2427 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2428 pr_info("%s: can't deregister ip6ip6\n", __func__); 2429 2430 if (ip6_tnl_mpls_supported() && 2431 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS)) 2432 pr_info("%s: can't deregister mplsip6\n", __func__); 2433 unregister_pernet_device(&ip6_tnl_net_ops); 2434 } 2435 2436 module_init(ip6_tunnel_init); 2437 module_exit(ip6_tunnel_cleanup); 2438