1 /* 2 * IPv6 tunneling device 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Ville Nuorvala <vnuorval@tcs.hut.fi> 7 * Yasuyuki Kozakai <kozakai@linux-ipv6.org> 8 * 9 * Based on: 10 * linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c 11 * 12 * RFC 2473 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 */ 20 21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 22 23 #include <linux/module.h> 24 #include <linux/capability.h> 25 #include <linux/errno.h> 26 #include <linux/types.h> 27 #include <linux/sockios.h> 28 #include <linux/icmp.h> 29 #include <linux/if.h> 30 #include <linux/in.h> 31 #include <linux/ip.h> 32 #include <linux/net.h> 33 #include <linux/in6.h> 34 #include <linux/netdevice.h> 35 #include <linux/if_arp.h> 36 #include <linux/icmpv6.h> 37 #include <linux/init.h> 38 #include <linux/route.h> 39 #include <linux/rtnetlink.h> 40 #include <linux/netfilter_ipv6.h> 41 #include <linux/slab.h> 42 #include <linux/hash.h> 43 #include <linux/etherdevice.h> 44 45 #include <linux/uaccess.h> 46 #include <linux/atomic.h> 47 48 #include <net/icmp.h> 49 #include <net/ip.h> 50 #include <net/ip_tunnels.h> 51 #include <net/ipv6.h> 52 #include <net/ip6_route.h> 53 #include <net/addrconf.h> 54 #include <net/ip6_tunnel.h> 55 #include <net/xfrm.h> 56 #include <net/dsfield.h> 57 #include <net/inet_ecn.h> 58 #include <net/net_namespace.h> 59 #include <net/netns/generic.h> 60 #include <net/dst_metadata.h> 61 62 MODULE_AUTHOR("Ville Nuorvala"); 63 MODULE_DESCRIPTION("IPv6 tunneling device"); 64 MODULE_LICENSE("GPL"); 65 MODULE_ALIAS_RTNL_LINK("ip6tnl"); 66 MODULE_ALIAS_NETDEV("ip6tnl0"); 67 68 #define IP6_TUNNEL_HASH_SIZE_SHIFT 5 69 #define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT) 70 71 static bool log_ecn_error = true; 72 module_param(log_ecn_error, bool, 0644); 73 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 74 75 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) 76 { 77 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); 78 79 return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT); 80 } 81 82 static int ip6_tnl_dev_init(struct net_device *dev); 83 static void ip6_tnl_dev_setup(struct net_device *dev); 84 static struct rtnl_link_ops ip6_link_ops __read_mostly; 85 86 static unsigned int ip6_tnl_net_id __read_mostly; 87 struct ip6_tnl_net { 88 /* the IPv6 tunnel fallback device */ 89 struct net_device *fb_tnl_dev; 90 /* lists for storing tunnels in use */ 91 struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE]; 92 struct ip6_tnl __rcu *tnls_wc[1]; 93 struct ip6_tnl __rcu **tnls[2]; 94 struct ip6_tnl __rcu *collect_md_tun; 95 }; 96 97 static struct net_device_stats *ip6_get_stats(struct net_device *dev) 98 { 99 struct pcpu_sw_netstats tmp, sum = { 0 }; 100 int i; 101 102 for_each_possible_cpu(i) { 103 unsigned int start; 104 const struct pcpu_sw_netstats *tstats = 105 per_cpu_ptr(dev->tstats, i); 106 107 do { 108 start = u64_stats_fetch_begin_irq(&tstats->syncp); 109 tmp.rx_packets = tstats->rx_packets; 110 tmp.rx_bytes = tstats->rx_bytes; 111 tmp.tx_packets = tstats->tx_packets; 112 tmp.tx_bytes = tstats->tx_bytes; 113 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 114 115 sum.rx_packets += tmp.rx_packets; 116 sum.rx_bytes += tmp.rx_bytes; 117 sum.tx_packets += tmp.tx_packets; 118 sum.tx_bytes += tmp.tx_bytes; 119 } 120 dev->stats.rx_packets = sum.rx_packets; 121 dev->stats.rx_bytes = sum.rx_bytes; 122 dev->stats.tx_packets = sum.tx_packets; 123 dev->stats.tx_bytes = sum.tx_bytes; 124 return &dev->stats; 125 } 126 127 /** 128 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 129 * @remote: the address of the tunnel exit-point 130 * @local: the address of the tunnel entry-point 131 * 132 * Return: 133 * tunnel matching given end-points if found, 134 * else fallback tunnel if its device is up, 135 * else %NULL 136 **/ 137 138 #define for_each_ip6_tunnel_rcu(start) \ 139 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 140 141 static struct ip6_tnl * 142 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local) 143 { 144 unsigned int hash = HASH(remote, local); 145 struct ip6_tnl *t; 146 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 147 struct in6_addr any; 148 149 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 150 if (ipv6_addr_equal(local, &t->parms.laddr) && 151 ipv6_addr_equal(remote, &t->parms.raddr) && 152 (t->dev->flags & IFF_UP)) 153 return t; 154 } 155 156 memset(&any, 0, sizeof(any)); 157 hash = HASH(&any, local); 158 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 159 if (ipv6_addr_equal(local, &t->parms.laddr) && 160 ipv6_addr_any(&t->parms.raddr) && 161 (t->dev->flags & IFF_UP)) 162 return t; 163 } 164 165 hash = HASH(remote, &any); 166 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 167 if (ipv6_addr_equal(remote, &t->parms.raddr) && 168 ipv6_addr_any(&t->parms.laddr) && 169 (t->dev->flags & IFF_UP)) 170 return t; 171 } 172 173 t = rcu_dereference(ip6n->collect_md_tun); 174 if (t && t->dev->flags & IFF_UP) 175 return t; 176 177 t = rcu_dereference(ip6n->tnls_wc[0]); 178 if (t && (t->dev->flags & IFF_UP)) 179 return t; 180 181 return NULL; 182 } 183 184 /** 185 * ip6_tnl_bucket - get head of list matching given tunnel parameters 186 * @p: parameters containing tunnel end-points 187 * 188 * Description: 189 * ip6_tnl_bucket() returns the head of the list matching the 190 * &struct in6_addr entries laddr and raddr in @p. 191 * 192 * Return: head of IPv6 tunnel list 193 **/ 194 195 static struct ip6_tnl __rcu ** 196 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p) 197 { 198 const struct in6_addr *remote = &p->raddr; 199 const struct in6_addr *local = &p->laddr; 200 unsigned int h = 0; 201 int prio = 0; 202 203 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 204 prio = 1; 205 h = HASH(remote, local); 206 } 207 return &ip6n->tnls[prio][h]; 208 } 209 210 /** 211 * ip6_tnl_link - add tunnel to hash table 212 * @t: tunnel to be added 213 **/ 214 215 static void 216 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 217 { 218 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); 219 220 if (t->parms.collect_md) 221 rcu_assign_pointer(ip6n->collect_md_tun, t); 222 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 223 rcu_assign_pointer(*tp, t); 224 } 225 226 /** 227 * ip6_tnl_unlink - remove tunnel from hash table 228 * @t: tunnel to be removed 229 **/ 230 231 static void 232 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 233 { 234 struct ip6_tnl __rcu **tp; 235 struct ip6_tnl *iter; 236 237 if (t->parms.collect_md) 238 rcu_assign_pointer(ip6n->collect_md_tun, NULL); 239 240 for (tp = ip6_tnl_bucket(ip6n, &t->parms); 241 (iter = rtnl_dereference(*tp)) != NULL; 242 tp = &iter->next) { 243 if (t == iter) { 244 rcu_assign_pointer(*tp, t->next); 245 break; 246 } 247 } 248 } 249 250 static void ip6_dev_free(struct net_device *dev) 251 { 252 struct ip6_tnl *t = netdev_priv(dev); 253 254 gro_cells_destroy(&t->gro_cells); 255 dst_cache_destroy(&t->dst_cache); 256 free_percpu(dev->tstats); 257 } 258 259 static int ip6_tnl_create2(struct net_device *dev) 260 { 261 struct ip6_tnl *t = netdev_priv(dev); 262 struct net *net = dev_net(dev); 263 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 264 int err; 265 266 t = netdev_priv(dev); 267 268 dev->rtnl_link_ops = &ip6_link_ops; 269 err = register_netdevice(dev); 270 if (err < 0) 271 goto out; 272 273 strcpy(t->parms.name, dev->name); 274 275 dev_hold(dev); 276 ip6_tnl_link(ip6n, t); 277 return 0; 278 279 out: 280 return err; 281 } 282 283 /** 284 * ip6_tnl_create - create a new tunnel 285 * @p: tunnel parameters 286 * @pt: pointer to new tunnel 287 * 288 * Description: 289 * Create tunnel matching given parameters. 290 * 291 * Return: 292 * created tunnel or error pointer 293 **/ 294 295 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 296 { 297 struct net_device *dev; 298 struct ip6_tnl *t; 299 char name[IFNAMSIZ]; 300 int err = -E2BIG; 301 302 if (p->name[0]) { 303 if (!dev_valid_name(p->name)) 304 goto failed; 305 strlcpy(name, p->name, IFNAMSIZ); 306 } else { 307 sprintf(name, "ip6tnl%%d"); 308 } 309 err = -ENOMEM; 310 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 311 ip6_tnl_dev_setup); 312 if (!dev) 313 goto failed; 314 315 dev_net_set(dev, net); 316 317 t = netdev_priv(dev); 318 t->parms = *p; 319 t->net = dev_net(dev); 320 err = ip6_tnl_create2(dev); 321 if (err < 0) 322 goto failed_free; 323 324 return t; 325 326 failed_free: 327 free_netdev(dev); 328 failed: 329 return ERR_PTR(err); 330 } 331 332 /** 333 * ip6_tnl_locate - find or create tunnel matching given parameters 334 * @p: tunnel parameters 335 * @create: != 0 if allowed to create new tunnel if no match found 336 * 337 * Description: 338 * ip6_tnl_locate() first tries to locate an existing tunnel 339 * based on @parms. If this is unsuccessful, but @create is set a new 340 * tunnel device is created and registered for use. 341 * 342 * Return: 343 * matching tunnel or error pointer 344 **/ 345 346 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 347 struct __ip6_tnl_parm *p, int create) 348 { 349 const struct in6_addr *remote = &p->raddr; 350 const struct in6_addr *local = &p->laddr; 351 struct ip6_tnl __rcu **tp; 352 struct ip6_tnl *t; 353 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 354 355 for (tp = ip6_tnl_bucket(ip6n, p); 356 (t = rtnl_dereference(*tp)) != NULL; 357 tp = &t->next) { 358 if (ipv6_addr_equal(local, &t->parms.laddr) && 359 ipv6_addr_equal(remote, &t->parms.raddr)) { 360 if (create) 361 return ERR_PTR(-EEXIST); 362 363 return t; 364 } 365 } 366 if (!create) 367 return ERR_PTR(-ENODEV); 368 return ip6_tnl_create(net, p); 369 } 370 371 /** 372 * ip6_tnl_dev_uninit - tunnel device uninitializer 373 * @dev: the device to be destroyed 374 * 375 * Description: 376 * ip6_tnl_dev_uninit() removes tunnel from its list 377 **/ 378 379 static void 380 ip6_tnl_dev_uninit(struct net_device *dev) 381 { 382 struct ip6_tnl *t = netdev_priv(dev); 383 struct net *net = t->net; 384 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 385 386 if (dev == ip6n->fb_tnl_dev) 387 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 388 else 389 ip6_tnl_unlink(ip6n, t); 390 dst_cache_reset(&t->dst_cache); 391 dev_put(dev); 392 } 393 394 /** 395 * parse_tvl_tnl_enc_lim - handle encapsulation limit option 396 * @skb: received socket buffer 397 * 398 * Return: 399 * 0 if none was found, 400 * else index to encapsulation limit 401 **/ 402 403 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) 404 { 405 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw; 406 unsigned int nhoff = raw - skb->data; 407 unsigned int off = nhoff + sizeof(*ipv6h); 408 u8 next, nexthdr = ipv6h->nexthdr; 409 410 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 411 struct ipv6_opt_hdr *hdr; 412 u16 optlen; 413 414 if (!pskb_may_pull(skb, off + sizeof(*hdr))) 415 break; 416 417 hdr = (struct ipv6_opt_hdr *)(skb->data + off); 418 if (nexthdr == NEXTHDR_FRAGMENT) { 419 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 420 if (frag_hdr->frag_off) 421 break; 422 optlen = 8; 423 } else if (nexthdr == NEXTHDR_AUTH) { 424 optlen = (hdr->hdrlen + 2) << 2; 425 } else { 426 optlen = ipv6_optlen(hdr); 427 } 428 /* cache hdr->nexthdr, since pskb_may_pull() might 429 * invalidate hdr 430 */ 431 next = hdr->nexthdr; 432 if (nexthdr == NEXTHDR_DEST) { 433 u16 i = 2; 434 435 /* Remember : hdr is no longer valid at this point. */ 436 if (!pskb_may_pull(skb, off + optlen)) 437 break; 438 439 while (1) { 440 struct ipv6_tlv_tnl_enc_lim *tel; 441 442 /* No more room for encapsulation limit */ 443 if (i + sizeof(*tel) > optlen) 444 break; 445 446 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i); 447 /* return index of option if found and valid */ 448 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 449 tel->length == 1) 450 return i + off - nhoff; 451 /* else jump to next option */ 452 if (tel->type) 453 i += tel->length + 2; 454 else 455 i++; 456 } 457 } 458 nexthdr = next; 459 off += optlen; 460 } 461 return 0; 462 } 463 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); 464 465 /** 466 * ip6_tnl_err - tunnel error handler 467 * 468 * Description: 469 * ip6_tnl_err() should handle errors in the tunnel according 470 * to the specifications in RFC 2473. 471 **/ 472 473 static int 474 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 475 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 476 { 477 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 478 struct net *net = dev_net(skb->dev); 479 u8 rel_type = ICMPV6_DEST_UNREACH; 480 u8 rel_code = ICMPV6_ADDR_UNREACH; 481 __u32 rel_info = 0; 482 struct ip6_tnl *t; 483 int err = -ENOENT; 484 int rel_msg = 0; 485 u8 tproto; 486 __u16 len; 487 488 /* If the packet doesn't contain the original IPv6 header we are 489 in trouble since we might need the source address for further 490 processing of the error. */ 491 492 rcu_read_lock(); 493 t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, &ipv6h->saddr); 494 if (!t) 495 goto out; 496 497 tproto = READ_ONCE(t->parms.proto); 498 if (tproto != ipproto && tproto != 0) 499 goto out; 500 501 err = 0; 502 503 switch (*type) { 504 struct ipv6_tlv_tnl_enc_lim *tel; 505 __u32 mtu, teli; 506 case ICMPV6_DEST_UNREACH: 507 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 508 t->parms.name); 509 rel_msg = 1; 510 break; 511 case ICMPV6_TIME_EXCEED: 512 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 513 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 514 t->parms.name); 515 rel_msg = 1; 516 } 517 break; 518 case ICMPV6_PARAMPROB: 519 teli = 0; 520 if ((*code) == ICMPV6_HDR_FIELD) 521 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 522 523 if (teli && teli == *info - 2) { 524 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 525 if (tel->encap_limit == 0) { 526 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 527 t->parms.name); 528 rel_msg = 1; 529 } 530 } else { 531 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 532 t->parms.name); 533 } 534 break; 535 case ICMPV6_PKT_TOOBIG: 536 ip6_update_pmtu(skb, net, htonl(*info), 0, 0, 537 sock_net_uid(net, NULL)); 538 mtu = *info - offset; 539 if (mtu < IPV6_MIN_MTU) 540 mtu = IPV6_MIN_MTU; 541 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len); 542 if (len > mtu) { 543 rel_type = ICMPV6_PKT_TOOBIG; 544 rel_code = 0; 545 rel_info = mtu; 546 rel_msg = 1; 547 } 548 break; 549 case NDISC_REDIRECT: 550 ip6_redirect(skb, net, skb->dev->ifindex, 0, 551 sock_net_uid(net, NULL)); 552 break; 553 } 554 555 *type = rel_type; 556 *code = rel_code; 557 *info = rel_info; 558 *msg = rel_msg; 559 560 out: 561 rcu_read_unlock(); 562 return err; 563 } 564 565 static int 566 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 567 u8 type, u8 code, int offset, __be32 info) 568 { 569 __u32 rel_info = ntohl(info); 570 const struct iphdr *eiph; 571 struct sk_buff *skb2; 572 int err, rel_msg = 0; 573 u8 rel_type = type; 574 u8 rel_code = code; 575 struct rtable *rt; 576 struct flowi4 fl4; 577 578 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 579 &rel_msg, &rel_info, offset); 580 if (err < 0) 581 return err; 582 583 if (rel_msg == 0) 584 return 0; 585 586 switch (rel_type) { 587 case ICMPV6_DEST_UNREACH: 588 if (rel_code != ICMPV6_ADDR_UNREACH) 589 return 0; 590 rel_type = ICMP_DEST_UNREACH; 591 rel_code = ICMP_HOST_UNREACH; 592 break; 593 case ICMPV6_PKT_TOOBIG: 594 if (rel_code != 0) 595 return 0; 596 rel_type = ICMP_DEST_UNREACH; 597 rel_code = ICMP_FRAG_NEEDED; 598 break; 599 default: 600 return 0; 601 } 602 603 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 604 return 0; 605 606 skb2 = skb_clone(skb, GFP_ATOMIC); 607 if (!skb2) 608 return 0; 609 610 skb_dst_drop(skb2); 611 612 skb_pull(skb2, offset); 613 skb_reset_network_header(skb2); 614 eiph = ip_hdr(skb2); 615 616 /* Try to guess incoming interface */ 617 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr, 618 0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 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, RT_TOS(eiph->tos), 0); 630 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL) { 631 if (!IS_ERR(rt)) 632 ip_rt_put(rt); 633 goto out; 634 } 635 skb_dst_set(skb2, &rt->dst); 636 } else { 637 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 638 skb2->dev) || 639 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL) 640 goto out; 641 } 642 643 /* change mtu on this route */ 644 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 645 if (rel_info > dst_mtu(skb_dst(skb2))) 646 goto out; 647 648 skb_dst_update_pmtu(skb2, rel_info); 649 } 650 651 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 652 653 out: 654 kfree_skb(skb2); 655 return 0; 656 } 657 658 static int 659 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 660 u8 type, u8 code, int offset, __be32 info) 661 { 662 __u32 rel_info = ntohl(info); 663 int err, rel_msg = 0; 664 u8 rel_type = type; 665 u8 rel_code = code; 666 667 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 668 &rel_msg, &rel_info, offset); 669 if (err < 0) 670 return err; 671 672 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 673 struct rt6_info *rt; 674 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 675 676 if (!skb2) 677 return 0; 678 679 skb_dst_drop(skb2); 680 skb_pull(skb2, offset); 681 skb_reset_network_header(skb2); 682 683 /* Try to guess incoming interface */ 684 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 685 NULL, 0, skb2, 0); 686 687 if (rt && rt->dst.dev) 688 skb2->dev = rt->dst.dev; 689 690 icmpv6_send(skb2, rel_type, rel_code, rel_info); 691 692 ip6_rt_put(rt); 693 694 kfree_skb(skb2); 695 } 696 697 return 0; 698 } 699 700 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 701 const struct ipv6hdr *ipv6h, 702 struct sk_buff *skb) 703 { 704 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 705 706 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 707 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 708 709 return IP6_ECN_decapsulate(ipv6h, skb); 710 } 711 712 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 713 const struct ipv6hdr *ipv6h, 714 struct sk_buff *skb) 715 { 716 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 717 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 718 719 return IP6_ECN_decapsulate(ipv6h, skb); 720 } 721 722 __u32 ip6_tnl_get_cap(struct ip6_tnl *t, 723 const struct in6_addr *laddr, 724 const struct in6_addr *raddr) 725 { 726 struct __ip6_tnl_parm *p = &t->parms; 727 int ltype = ipv6_addr_type(laddr); 728 int rtype = ipv6_addr_type(raddr); 729 __u32 flags = 0; 730 731 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { 732 flags = IP6_TNL_F_CAP_PER_PACKET; 733 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 734 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 735 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 736 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 737 if (ltype&IPV6_ADDR_UNICAST) 738 flags |= IP6_TNL_F_CAP_XMIT; 739 if (rtype&IPV6_ADDR_UNICAST) 740 flags |= IP6_TNL_F_CAP_RCV; 741 } 742 return flags; 743 } 744 EXPORT_SYMBOL(ip6_tnl_get_cap); 745 746 /* called with rcu_read_lock() */ 747 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, 748 const struct in6_addr *laddr, 749 const struct in6_addr *raddr) 750 { 751 struct __ip6_tnl_parm *p = &t->parms; 752 int ret = 0; 753 struct net *net = t->net; 754 755 if ((p->flags & IP6_TNL_F_CAP_RCV) || 756 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 757 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { 758 struct net_device *ldev = NULL; 759 760 if (p->link) 761 ldev = dev_get_by_index_rcu(net, p->link); 762 763 if ((ipv6_addr_is_multicast(laddr) || 764 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false, 765 0, IFA_F_TENTATIVE))) && 766 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) || 767 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true, 768 0, IFA_F_TENTATIVE)))) 769 ret = 1; 770 } 771 return ret; 772 } 773 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); 774 775 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb, 776 const struct tnl_ptk_info *tpi, 777 struct metadata_dst *tun_dst, 778 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 779 const struct ipv6hdr *ipv6h, 780 struct sk_buff *skb), 781 bool log_ecn_err) 782 { 783 struct pcpu_sw_netstats *tstats; 784 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 785 int err; 786 787 if ((!(tpi->flags & TUNNEL_CSUM) && 788 (tunnel->parms.i_flags & TUNNEL_CSUM)) || 789 ((tpi->flags & TUNNEL_CSUM) && 790 !(tunnel->parms.i_flags & TUNNEL_CSUM))) { 791 tunnel->dev->stats.rx_crc_errors++; 792 tunnel->dev->stats.rx_errors++; 793 goto drop; 794 } 795 796 if (tunnel->parms.i_flags & TUNNEL_SEQ) { 797 if (!(tpi->flags & TUNNEL_SEQ) || 798 (tunnel->i_seqno && 799 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 800 tunnel->dev->stats.rx_fifo_errors++; 801 tunnel->dev->stats.rx_errors++; 802 goto drop; 803 } 804 tunnel->i_seqno = ntohl(tpi->seq) + 1; 805 } 806 807 skb->protocol = tpi->proto; 808 809 /* Warning: All skb pointers will be invalidated! */ 810 if (tunnel->dev->type == ARPHRD_ETHER) { 811 if (!pskb_may_pull(skb, ETH_HLEN)) { 812 tunnel->dev->stats.rx_length_errors++; 813 tunnel->dev->stats.rx_errors++; 814 goto drop; 815 } 816 817 ipv6h = ipv6_hdr(skb); 818 skb->protocol = eth_type_trans(skb, tunnel->dev); 819 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 820 } else { 821 skb->dev = tunnel->dev; 822 } 823 824 skb_reset_network_header(skb); 825 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 826 827 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 828 829 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb); 830 if (unlikely(err)) { 831 if (log_ecn_err) 832 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n", 833 &ipv6h->saddr, 834 ipv6_get_dsfield(ipv6h)); 835 if (err > 1) { 836 ++tunnel->dev->stats.rx_frame_errors; 837 ++tunnel->dev->stats.rx_errors; 838 goto drop; 839 } 840 } 841 842 tstats = this_cpu_ptr(tunnel->dev->tstats); 843 u64_stats_update_begin(&tstats->syncp); 844 tstats->rx_packets++; 845 tstats->rx_bytes += skb->len; 846 u64_stats_update_end(&tstats->syncp); 847 848 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 849 850 if (tun_dst) 851 skb_dst_set(skb, (struct dst_entry *)tun_dst); 852 853 gro_cells_receive(&tunnel->gro_cells, skb); 854 return 0; 855 856 drop: 857 if (tun_dst) 858 dst_release((struct dst_entry *)tun_dst); 859 kfree_skb(skb); 860 return 0; 861 } 862 863 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb, 864 const struct tnl_ptk_info *tpi, 865 struct metadata_dst *tun_dst, 866 bool log_ecn_err) 867 { 868 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, ip6ip6_dscp_ecn_decapsulate, 869 log_ecn_err); 870 } 871 EXPORT_SYMBOL(ip6_tnl_rcv); 872 873 static const struct tnl_ptk_info tpi_v6 = { 874 /* no tunnel info required for ipxip6. */ 875 .proto = htons(ETH_P_IPV6), 876 }; 877 878 static const struct tnl_ptk_info tpi_v4 = { 879 /* no tunnel info required for ipxip6. */ 880 .proto = htons(ETH_P_IP), 881 }; 882 883 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto, 884 const struct tnl_ptk_info *tpi, 885 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 886 const struct ipv6hdr *ipv6h, 887 struct sk_buff *skb)) 888 { 889 struct ip6_tnl *t; 890 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 891 struct metadata_dst *tun_dst = NULL; 892 int ret = -1; 893 894 rcu_read_lock(); 895 t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr); 896 897 if (t) { 898 u8 tproto = READ_ONCE(t->parms.proto); 899 900 if (tproto != ipproto && tproto != 0) 901 goto drop; 902 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 903 goto drop; 904 ipv6h = ipv6_hdr(skb); 905 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) 906 goto drop; 907 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 908 goto drop; 909 if (t->parms.collect_md) { 910 tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0); 911 if (!tun_dst) 912 goto drop; 913 } 914 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate, 915 log_ecn_error); 916 } 917 918 rcu_read_unlock(); 919 920 return ret; 921 922 drop: 923 rcu_read_unlock(); 924 kfree_skb(skb); 925 return 0; 926 } 927 928 static int ip4ip6_rcv(struct sk_buff *skb) 929 { 930 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4, 931 ip4ip6_dscp_ecn_decapsulate); 932 } 933 934 static int ip6ip6_rcv(struct sk_buff *skb) 935 { 936 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6, 937 ip6ip6_dscp_ecn_decapsulate); 938 } 939 940 struct ipv6_tel_txoption { 941 struct ipv6_txoptions ops; 942 __u8 dst_opt[8]; 943 }; 944 945 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 946 { 947 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 948 949 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 950 opt->dst_opt[3] = 1; 951 opt->dst_opt[4] = encap_limit; 952 opt->dst_opt[5] = IPV6_TLV_PADN; 953 opt->dst_opt[6] = 1; 954 955 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt; 956 opt->ops.opt_nflen = 8; 957 } 958 959 /** 960 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 961 * @t: the outgoing tunnel device 962 * @hdr: IPv6 header from the incoming packet 963 * 964 * Description: 965 * Avoid trivial tunneling loop by checking that tunnel exit-point 966 * doesn't match source of incoming packet. 967 * 968 * Return: 969 * 1 if conflict, 970 * 0 else 971 **/ 972 973 static inline bool 974 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 975 { 976 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 977 } 978 979 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, 980 const struct in6_addr *laddr, 981 const struct in6_addr *raddr) 982 { 983 struct __ip6_tnl_parm *p = &t->parms; 984 int ret = 0; 985 struct net *net = t->net; 986 987 if (t->parms.collect_md) 988 return 1; 989 990 if ((p->flags & IP6_TNL_F_CAP_XMIT) || 991 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && 992 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) { 993 struct net_device *ldev = NULL; 994 995 rcu_read_lock(); 996 if (p->link) 997 ldev = dev_get_by_index_rcu(net, p->link); 998 999 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false, 1000 0, IFA_F_TENTATIVE))) 1001 pr_warn("%s xmit: Local address not yet configured!\n", 1002 p->name); 1003 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) && 1004 !ipv6_addr_is_multicast(raddr) && 1005 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev, 1006 true, 0, IFA_F_TENTATIVE))) 1007 pr_warn("%s xmit: Routing loop! Remote address found on this node!\n", 1008 p->name); 1009 else 1010 ret = 1; 1011 rcu_read_unlock(); 1012 } 1013 return ret; 1014 } 1015 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); 1016 1017 /** 1018 * ip6_tnl_xmit - encapsulate packet and send 1019 * @skb: the outgoing socket buffer 1020 * @dev: the outgoing tunnel device 1021 * @dsfield: dscp code for outer header 1022 * @fl6: flow of tunneled packet 1023 * @encap_limit: encapsulation limit 1024 * @pmtu: Path MTU is stored if packet is too big 1025 * @proto: next header value 1026 * 1027 * Description: 1028 * Build new header and do some sanity checks on the packet before sending 1029 * it. 1030 * 1031 * Return: 1032 * 0 on success 1033 * -1 fail 1034 * %-EMSGSIZE message too big. return mtu in this case. 1035 **/ 1036 1037 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, 1038 struct flowi6 *fl6, int encap_limit, __u32 *pmtu, 1039 __u8 proto) 1040 { 1041 struct ip6_tnl *t = netdev_priv(dev); 1042 struct net *net = t->net; 1043 struct net_device_stats *stats = &t->dev->stats; 1044 struct ipv6hdr *ipv6h; 1045 struct ipv6_tel_txoption opt; 1046 struct dst_entry *dst = NULL, *ndst = NULL; 1047 struct net_device *tdev; 1048 int mtu; 1049 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0; 1050 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; 1051 unsigned int max_headroom = psh_hlen; 1052 bool use_cache = false; 1053 u8 hop_limit; 1054 int err = -1; 1055 1056 if (t->parms.collect_md) { 1057 hop_limit = skb_tunnel_info(skb)->key.ttl; 1058 goto route_lookup; 1059 } else { 1060 hop_limit = t->parms.hop_limit; 1061 } 1062 1063 /* NBMA tunnel */ 1064 if (ipv6_addr_any(&t->parms.raddr)) { 1065 if (skb->protocol == htons(ETH_P_IPV6)) { 1066 struct in6_addr *addr6; 1067 struct neighbour *neigh; 1068 int addr_type; 1069 1070 if (!skb_dst(skb)) 1071 goto tx_err_link_failure; 1072 1073 neigh = dst_neigh_lookup(skb_dst(skb), 1074 &ipv6_hdr(skb)->daddr); 1075 if (!neigh) 1076 goto tx_err_link_failure; 1077 1078 addr6 = (struct in6_addr *)&neigh->primary_key; 1079 addr_type = ipv6_addr_type(addr6); 1080 1081 if (addr_type == IPV6_ADDR_ANY) 1082 addr6 = &ipv6_hdr(skb)->daddr; 1083 1084 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr)); 1085 neigh_release(neigh); 1086 } 1087 } else if (t->parms.proto != 0 && !(t->parms.flags & 1088 (IP6_TNL_F_USE_ORIG_TCLASS | 1089 IP6_TNL_F_USE_ORIG_FWMARK))) { 1090 /* enable the cache only if neither the outer protocol nor the 1091 * routing decision depends on the current inner header value 1092 */ 1093 use_cache = true; 1094 } 1095 1096 if (use_cache) 1097 dst = dst_cache_get(&t->dst_cache); 1098 1099 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr)) 1100 goto tx_err_link_failure; 1101 1102 if (!dst) { 1103 route_lookup: 1104 /* add dsfield to flowlabel for route lookup */ 1105 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel); 1106 1107 dst = ip6_route_output(net, NULL, fl6); 1108 1109 if (dst->error) 1110 goto tx_err_link_failure; 1111 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 1112 if (IS_ERR(dst)) { 1113 err = PTR_ERR(dst); 1114 dst = NULL; 1115 goto tx_err_link_failure; 1116 } 1117 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) && 1118 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev, 1119 &fl6->daddr, 0, &fl6->saddr)) 1120 goto tx_err_link_failure; 1121 ndst = dst; 1122 } 1123 1124 tdev = dst->dev; 1125 1126 if (tdev == dev) { 1127 stats->collisions++; 1128 net_warn_ratelimited("%s: Local routing loop detected!\n", 1129 t->parms.name); 1130 goto tx_err_dst_release; 1131 } 1132 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen; 1133 if (encap_limit >= 0) { 1134 max_headroom += 8; 1135 mtu -= 8; 1136 } 1137 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ? 1138 IPV6_MIN_MTU : IPV4_MIN_MTU); 1139 1140 skb_dst_update_pmtu(skb, mtu); 1141 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) { 1142 *pmtu = mtu; 1143 err = -EMSGSIZE; 1144 goto tx_err_dst_release; 1145 } 1146 1147 if (t->err_count > 0) { 1148 if (time_before(jiffies, 1149 t->err_time + IP6TUNNEL_ERR_TIMEO)) { 1150 t->err_count--; 1151 1152 dst_link_failure(skb); 1153 } else { 1154 t->err_count = 0; 1155 } 1156 } 1157 1158 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 1159 1160 /* 1161 * Okay, now see if we can stuff it in the buffer as-is. 1162 */ 1163 max_headroom += LL_RESERVED_SPACE(tdev); 1164 1165 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 1166 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 1167 struct sk_buff *new_skb; 1168 1169 new_skb = skb_realloc_headroom(skb, max_headroom); 1170 if (!new_skb) 1171 goto tx_err_dst_release; 1172 1173 if (skb->sk) 1174 skb_set_owner_w(new_skb, skb->sk); 1175 consume_skb(skb); 1176 skb = new_skb; 1177 } 1178 1179 if (t->parms.collect_md) { 1180 if (t->encap.type != TUNNEL_ENCAP_NONE) 1181 goto tx_err_dst_release; 1182 } else { 1183 if (use_cache && ndst) 1184 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr); 1185 } 1186 skb_dst_set(skb, dst); 1187 1188 if (hop_limit == 0) { 1189 if (skb->protocol == htons(ETH_P_IP)) 1190 hop_limit = ip_hdr(skb)->ttl; 1191 else if (skb->protocol == htons(ETH_P_IPV6)) 1192 hop_limit = ipv6_hdr(skb)->hop_limit; 1193 else 1194 hop_limit = ip6_dst_hoplimit(dst); 1195 } 1196 1197 /* Calculate max headroom for all the headers and adjust 1198 * needed_headroom if necessary. 1199 */ 1200 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) 1201 + dst->header_len + t->hlen; 1202 if (max_headroom > dev->needed_headroom) 1203 dev->needed_headroom = max_headroom; 1204 1205 err = ip6_tnl_encap(skb, t, &proto, fl6); 1206 if (err) 1207 return err; 1208 1209 if (encap_limit >= 0) { 1210 init_tel_txopt(&opt, encap_limit); 1211 ipv6_push_frag_opts(skb, &opt.ops, &proto); 1212 } 1213 1214 skb_push(skb, sizeof(struct ipv6hdr)); 1215 skb_reset_network_header(skb); 1216 ipv6h = ipv6_hdr(skb); 1217 ip6_flow_hdr(ipv6h, dsfield, 1218 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 1219 ipv6h->hop_limit = hop_limit; 1220 ipv6h->nexthdr = proto; 1221 ipv6h->saddr = fl6->saddr; 1222 ipv6h->daddr = fl6->daddr; 1223 ip6tunnel_xmit(NULL, skb, dev); 1224 return 0; 1225 tx_err_link_failure: 1226 stats->tx_carrier_errors++; 1227 dst_link_failure(skb); 1228 tx_err_dst_release: 1229 dst_release(dst); 1230 return err; 1231 } 1232 EXPORT_SYMBOL(ip6_tnl_xmit); 1233 1234 static inline int 1235 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1236 { 1237 struct ip6_tnl *t = netdev_priv(dev); 1238 const struct iphdr *iph; 1239 int encap_limit = -1; 1240 struct flowi6 fl6; 1241 __u8 dsfield; 1242 __u32 mtu; 1243 u8 tproto; 1244 int err; 1245 1246 /* ensure we can access the full inner ip header */ 1247 if (!pskb_may_pull(skb, sizeof(struct iphdr))) 1248 return -1; 1249 1250 iph = ip_hdr(skb); 1251 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 1252 1253 tproto = READ_ONCE(t->parms.proto); 1254 if (tproto != IPPROTO_IPIP && tproto != 0) 1255 return -1; 1256 1257 if (t->parms.collect_md) { 1258 struct ip_tunnel_info *tun_info; 1259 const struct ip_tunnel_key *key; 1260 1261 tun_info = skb_tunnel_info(skb); 1262 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1263 ip_tunnel_info_af(tun_info) != AF_INET6)) 1264 return -1; 1265 key = &tun_info->key; 1266 memset(&fl6, 0, sizeof(fl6)); 1267 fl6.flowi6_proto = IPPROTO_IPIP; 1268 fl6.saddr = key->u.ipv6.src; 1269 fl6.daddr = key->u.ipv6.dst; 1270 fl6.flowlabel = key->label; 1271 dsfield = key->tos; 1272 } else { 1273 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1274 encap_limit = t->parms.encap_limit; 1275 1276 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1277 fl6.flowi6_proto = IPPROTO_IPIP; 1278 1279 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1280 dsfield = ipv4_get_dsfield(iph); 1281 else 1282 dsfield = ip6_tclass(t->parms.flowinfo); 1283 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1284 fl6.flowi6_mark = skb->mark; 1285 else 1286 fl6.flowi6_mark = t->parms.fwmark; 1287 } 1288 1289 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1290 1291 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1292 return -1; 1293 1294 dsfield = INET_ECN_encapsulate(dsfield, ipv4_get_dsfield(iph)); 1295 1296 skb_set_inner_ipproto(skb, IPPROTO_IPIP); 1297 1298 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1299 IPPROTO_IPIP); 1300 if (err != 0) { 1301 /* XXX: send ICMP error even if DF is not set. */ 1302 if (err == -EMSGSIZE) 1303 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 1304 htonl(mtu)); 1305 return -1; 1306 } 1307 1308 return 0; 1309 } 1310 1311 static inline int 1312 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1313 { 1314 struct ip6_tnl *t = netdev_priv(dev); 1315 struct ipv6hdr *ipv6h; 1316 int encap_limit = -1; 1317 __u16 offset; 1318 struct flowi6 fl6; 1319 __u8 dsfield; 1320 __u32 mtu; 1321 u8 tproto; 1322 int err; 1323 1324 if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h)))) 1325 return -1; 1326 1327 ipv6h = ipv6_hdr(skb); 1328 tproto = READ_ONCE(t->parms.proto); 1329 if ((tproto != IPPROTO_IPV6 && tproto != 0) || 1330 ip6_tnl_addr_conflict(t, ipv6h)) 1331 return -1; 1332 1333 if (t->parms.collect_md) { 1334 struct ip_tunnel_info *tun_info; 1335 const struct ip_tunnel_key *key; 1336 1337 tun_info = skb_tunnel_info(skb); 1338 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 1339 ip_tunnel_info_af(tun_info) != AF_INET6)) 1340 return -1; 1341 key = &tun_info->key; 1342 memset(&fl6, 0, sizeof(fl6)); 1343 fl6.flowi6_proto = IPPROTO_IPV6; 1344 fl6.saddr = key->u.ipv6.src; 1345 fl6.daddr = key->u.ipv6.dst; 1346 fl6.flowlabel = key->label; 1347 dsfield = key->tos; 1348 } else { 1349 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 1350 /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */ 1351 ipv6h = ipv6_hdr(skb); 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_send(skb, ICMPV6_PARAMPROB, 1358 ICMPV6_HDR_FIELD, offset + 2); 1359 return -1; 1360 } 1361 encap_limit = tel->encap_limit - 1; 1362 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) { 1363 encap_limit = t->parms.encap_limit; 1364 } 1365 1366 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 1367 fl6.flowi6_proto = IPPROTO_IPV6; 1368 1369 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1370 dsfield = ipv6_get_dsfield(ipv6h); 1371 else 1372 dsfield = ip6_tclass(t->parms.flowinfo); 1373 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1374 fl6.flowlabel |= ip6_flowlabel(ipv6h); 1375 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1376 fl6.flowi6_mark = skb->mark; 1377 else 1378 fl6.flowi6_mark = t->parms.fwmark; 1379 } 1380 1381 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 1382 1383 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6)) 1384 return -1; 1385 1386 dsfield = INET_ECN_encapsulate(dsfield, ipv6_get_dsfield(ipv6h)); 1387 1388 skb_set_inner_ipproto(skb, IPPROTO_IPV6); 1389 1390 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 1391 IPPROTO_IPV6); 1392 if (err != 0) { 1393 if (err == -EMSGSIZE) 1394 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1395 return -1; 1396 } 1397 1398 return 0; 1399 } 1400 1401 static netdev_tx_t 1402 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev) 1403 { 1404 struct ip6_tnl *t = netdev_priv(dev); 1405 struct net_device_stats *stats = &t->dev->stats; 1406 int ret; 1407 1408 switch (skb->protocol) { 1409 case htons(ETH_P_IP): 1410 ret = ip4ip6_tnl_xmit(skb, dev); 1411 break; 1412 case htons(ETH_P_IPV6): 1413 ret = ip6ip6_tnl_xmit(skb, dev); 1414 break; 1415 default: 1416 goto tx_err; 1417 } 1418 1419 if (ret < 0) 1420 goto tx_err; 1421 1422 return NETDEV_TX_OK; 1423 1424 tx_err: 1425 stats->tx_errors++; 1426 stats->tx_dropped++; 1427 kfree_skb(skb); 1428 return NETDEV_TX_OK; 1429 } 1430 1431 static void ip6_tnl_link_config(struct ip6_tnl *t) 1432 { 1433 struct net_device *dev = t->dev; 1434 struct __ip6_tnl_parm *p = &t->parms; 1435 struct flowi6 *fl6 = &t->fl.u.ip6; 1436 int t_hlen; 1437 1438 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1439 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1440 1441 /* Set up flowi template */ 1442 fl6->saddr = p->laddr; 1443 fl6->daddr = p->raddr; 1444 fl6->flowi6_oif = p->link; 1445 fl6->flowlabel = 0; 1446 1447 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1448 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1449 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1450 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1451 1452 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1453 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1454 1455 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1456 dev->flags |= IFF_POINTOPOINT; 1457 else 1458 dev->flags &= ~IFF_POINTOPOINT; 1459 1460 t->tun_hlen = 0; 1461 t->hlen = t->encap_hlen + t->tun_hlen; 1462 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1463 1464 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1465 int strict = (ipv6_addr_type(&p->raddr) & 1466 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1467 1468 struct rt6_info *rt = rt6_lookup(t->net, 1469 &p->raddr, &p->laddr, 1470 p->link, NULL, strict); 1471 1472 if (!rt) 1473 return; 1474 1475 if (rt->dst.dev) { 1476 dev->hard_header_len = rt->dst.dev->hard_header_len + 1477 t_hlen; 1478 1479 dev->mtu = rt->dst.dev->mtu - t_hlen; 1480 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1481 dev->mtu -= 8; 1482 1483 if (dev->mtu < IPV6_MIN_MTU) 1484 dev->mtu = IPV6_MIN_MTU; 1485 } 1486 ip6_rt_put(rt); 1487 } 1488 } 1489 1490 /** 1491 * ip6_tnl_change - update the tunnel parameters 1492 * @t: tunnel to be changed 1493 * @p: tunnel configuration parameters 1494 * 1495 * Description: 1496 * ip6_tnl_change() updates the tunnel parameters 1497 **/ 1498 1499 static int 1500 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 1501 { 1502 t->parms.laddr = p->laddr; 1503 t->parms.raddr = p->raddr; 1504 t->parms.flags = p->flags; 1505 t->parms.hop_limit = p->hop_limit; 1506 t->parms.encap_limit = p->encap_limit; 1507 t->parms.flowinfo = p->flowinfo; 1508 t->parms.link = p->link; 1509 t->parms.proto = p->proto; 1510 t->parms.fwmark = p->fwmark; 1511 dst_cache_reset(&t->dst_cache); 1512 ip6_tnl_link_config(t); 1513 return 0; 1514 } 1515 1516 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1517 { 1518 struct net *net = t->net; 1519 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1520 int err; 1521 1522 ip6_tnl_unlink(ip6n, t); 1523 synchronize_net(); 1524 err = ip6_tnl_change(t, p); 1525 ip6_tnl_link(ip6n, t); 1526 netdev_state_change(t->dev); 1527 return err; 1528 } 1529 1530 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 1531 { 1532 /* for default tnl0 device allow to change only the proto */ 1533 t->parms.proto = p->proto; 1534 netdev_state_change(t->dev); 1535 return 0; 1536 } 1537 1538 static void 1539 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) 1540 { 1541 p->laddr = u->laddr; 1542 p->raddr = u->raddr; 1543 p->flags = u->flags; 1544 p->hop_limit = u->hop_limit; 1545 p->encap_limit = u->encap_limit; 1546 p->flowinfo = u->flowinfo; 1547 p->link = u->link; 1548 p->proto = u->proto; 1549 memcpy(p->name, u->name, sizeof(u->name)); 1550 } 1551 1552 static void 1553 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) 1554 { 1555 u->laddr = p->laddr; 1556 u->raddr = p->raddr; 1557 u->flags = p->flags; 1558 u->hop_limit = p->hop_limit; 1559 u->encap_limit = p->encap_limit; 1560 u->flowinfo = p->flowinfo; 1561 u->link = p->link; 1562 u->proto = p->proto; 1563 memcpy(u->name, p->name, sizeof(u->name)); 1564 } 1565 1566 /** 1567 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1568 * @dev: virtual device associated with tunnel 1569 * @ifr: parameters passed from userspace 1570 * @cmd: command to be performed 1571 * 1572 * Description: 1573 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1574 * from userspace. 1575 * 1576 * The possible commands are the following: 1577 * %SIOCGETTUNNEL: get tunnel parameters for device 1578 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1579 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1580 * %SIOCDELTUNNEL: delete tunnel 1581 * 1582 * The fallback device "ip6tnl0", created during module 1583 * initialization, can be used for creating other tunnel devices. 1584 * 1585 * Return: 1586 * 0 on success, 1587 * %-EFAULT if unable to copy data to or from userspace, 1588 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1589 * %-EINVAL if passed tunnel parameters are invalid, 1590 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1591 * %-ENODEV if attempting to change or delete a nonexisting device 1592 **/ 1593 1594 static int 1595 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1596 { 1597 int err = 0; 1598 struct ip6_tnl_parm p; 1599 struct __ip6_tnl_parm p1; 1600 struct ip6_tnl *t = netdev_priv(dev); 1601 struct net *net = t->net; 1602 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1603 1604 memset(&p1, 0, sizeof(p1)); 1605 1606 switch (cmd) { 1607 case SIOCGETTUNNEL: 1608 if (dev == ip6n->fb_tnl_dev) { 1609 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1610 err = -EFAULT; 1611 break; 1612 } 1613 ip6_tnl_parm_from_user(&p1, &p); 1614 t = ip6_tnl_locate(net, &p1, 0); 1615 if (IS_ERR(t)) 1616 t = netdev_priv(dev); 1617 } else { 1618 memset(&p, 0, sizeof(p)); 1619 } 1620 ip6_tnl_parm_to_user(&p, &t->parms); 1621 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) { 1622 err = -EFAULT; 1623 } 1624 break; 1625 case SIOCADDTUNNEL: 1626 case SIOCCHGTUNNEL: 1627 err = -EPERM; 1628 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1629 break; 1630 err = -EFAULT; 1631 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1632 break; 1633 err = -EINVAL; 1634 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1635 p.proto != 0) 1636 break; 1637 ip6_tnl_parm_from_user(&p1, &p); 1638 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); 1639 if (cmd == SIOCCHGTUNNEL) { 1640 if (!IS_ERR(t)) { 1641 if (t->dev != dev) { 1642 err = -EEXIST; 1643 break; 1644 } 1645 } else 1646 t = netdev_priv(dev); 1647 if (dev == ip6n->fb_tnl_dev) 1648 err = ip6_tnl0_update(t, &p1); 1649 else 1650 err = ip6_tnl_update(t, &p1); 1651 } 1652 if (!IS_ERR(t)) { 1653 err = 0; 1654 ip6_tnl_parm_to_user(&p, &t->parms); 1655 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1656 err = -EFAULT; 1657 1658 } else { 1659 err = PTR_ERR(t); 1660 } 1661 break; 1662 case SIOCDELTUNNEL: 1663 err = -EPERM; 1664 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1665 break; 1666 1667 if (dev == ip6n->fb_tnl_dev) { 1668 err = -EFAULT; 1669 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1670 break; 1671 err = -ENOENT; 1672 ip6_tnl_parm_from_user(&p1, &p); 1673 t = ip6_tnl_locate(net, &p1, 0); 1674 if (IS_ERR(t)) 1675 break; 1676 err = -EPERM; 1677 if (t->dev == ip6n->fb_tnl_dev) 1678 break; 1679 dev = t->dev; 1680 } 1681 err = 0; 1682 unregister_netdevice(dev); 1683 break; 1684 default: 1685 err = -EINVAL; 1686 } 1687 return err; 1688 } 1689 1690 /** 1691 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1692 * @dev: virtual device associated with tunnel 1693 * @new_mtu: the new mtu 1694 * 1695 * Return: 1696 * 0 on success, 1697 * %-EINVAL if mtu too small 1698 **/ 1699 1700 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1701 { 1702 struct ip6_tnl *tnl = netdev_priv(dev); 1703 1704 if (tnl->parms.proto == IPPROTO_IPV6) { 1705 if (new_mtu < IPV6_MIN_MTU) 1706 return -EINVAL; 1707 } else { 1708 if (new_mtu < ETH_MIN_MTU) 1709 return -EINVAL; 1710 } 1711 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) { 1712 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len) 1713 return -EINVAL; 1714 } else { 1715 if (new_mtu > IP_MAX_MTU - dev->hard_header_len) 1716 return -EINVAL; 1717 } 1718 dev->mtu = new_mtu; 1719 return 0; 1720 } 1721 EXPORT_SYMBOL(ip6_tnl_change_mtu); 1722 1723 int ip6_tnl_get_iflink(const struct net_device *dev) 1724 { 1725 struct ip6_tnl *t = netdev_priv(dev); 1726 1727 return t->parms.link; 1728 } 1729 EXPORT_SYMBOL(ip6_tnl_get_iflink); 1730 1731 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, 1732 unsigned int num) 1733 { 1734 if (num >= MAX_IPTUN_ENCAP_OPS) 1735 return -ERANGE; 1736 1737 return !cmpxchg((const struct ip6_tnl_encap_ops **) 1738 &ip6tun_encaps[num], 1739 NULL, ops) ? 0 : -1; 1740 } 1741 EXPORT_SYMBOL(ip6_tnl_encap_add_ops); 1742 1743 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, 1744 unsigned int num) 1745 { 1746 int ret; 1747 1748 if (num >= MAX_IPTUN_ENCAP_OPS) 1749 return -ERANGE; 1750 1751 ret = (cmpxchg((const struct ip6_tnl_encap_ops **) 1752 &ip6tun_encaps[num], 1753 ops, NULL) == ops) ? 0 : -1; 1754 1755 synchronize_net(); 1756 1757 return ret; 1758 } 1759 EXPORT_SYMBOL(ip6_tnl_encap_del_ops); 1760 1761 int ip6_tnl_encap_setup(struct ip6_tnl *t, 1762 struct ip_tunnel_encap *ipencap) 1763 { 1764 int hlen; 1765 1766 memset(&t->encap, 0, sizeof(t->encap)); 1767 1768 hlen = ip6_encap_hlen(ipencap); 1769 if (hlen < 0) 1770 return hlen; 1771 1772 t->encap.type = ipencap->type; 1773 t->encap.sport = ipencap->sport; 1774 t->encap.dport = ipencap->dport; 1775 t->encap.flags = ipencap->flags; 1776 1777 t->encap_hlen = hlen; 1778 t->hlen = t->encap_hlen + t->tun_hlen; 1779 1780 return 0; 1781 } 1782 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); 1783 1784 static const struct net_device_ops ip6_tnl_netdev_ops = { 1785 .ndo_init = ip6_tnl_dev_init, 1786 .ndo_uninit = ip6_tnl_dev_uninit, 1787 .ndo_start_xmit = ip6_tnl_start_xmit, 1788 .ndo_do_ioctl = ip6_tnl_ioctl, 1789 .ndo_change_mtu = ip6_tnl_change_mtu, 1790 .ndo_get_stats = ip6_get_stats, 1791 .ndo_get_iflink = ip6_tnl_get_iflink, 1792 }; 1793 1794 #define IPXIPX_FEATURES (NETIF_F_SG | \ 1795 NETIF_F_FRAGLIST | \ 1796 NETIF_F_HIGHDMA | \ 1797 NETIF_F_GSO_SOFTWARE | \ 1798 NETIF_F_HW_CSUM) 1799 1800 /** 1801 * ip6_tnl_dev_setup - setup virtual tunnel device 1802 * @dev: virtual device associated with tunnel 1803 * 1804 * Description: 1805 * Initialize function pointers and device parameters 1806 **/ 1807 1808 static void ip6_tnl_dev_setup(struct net_device *dev) 1809 { 1810 dev->netdev_ops = &ip6_tnl_netdev_ops; 1811 dev->needs_free_netdev = true; 1812 dev->priv_destructor = ip6_dev_free; 1813 1814 dev->type = ARPHRD_TUNNEL6; 1815 dev->flags |= IFF_NOARP; 1816 dev->addr_len = sizeof(struct in6_addr); 1817 dev->features |= NETIF_F_LLTX; 1818 netif_keep_dst(dev); 1819 1820 dev->features |= IPXIPX_FEATURES; 1821 dev->hw_features |= IPXIPX_FEATURES; 1822 1823 /* This perm addr will be used as interface identifier by IPv6 */ 1824 dev->addr_assign_type = NET_ADDR_RANDOM; 1825 eth_random_addr(dev->perm_addr); 1826 } 1827 1828 1829 /** 1830 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1831 * @dev: virtual device associated with tunnel 1832 **/ 1833 1834 static inline int 1835 ip6_tnl_dev_init_gen(struct net_device *dev) 1836 { 1837 struct ip6_tnl *t = netdev_priv(dev); 1838 int ret; 1839 int t_hlen; 1840 1841 t->dev = dev; 1842 t->net = dev_net(dev); 1843 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1844 if (!dev->tstats) 1845 return -ENOMEM; 1846 1847 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL); 1848 if (ret) 1849 goto free_stats; 1850 1851 ret = gro_cells_init(&t->gro_cells, dev); 1852 if (ret) 1853 goto destroy_dst; 1854 1855 t->tun_hlen = 0; 1856 t->hlen = t->encap_hlen + t->tun_hlen; 1857 t_hlen = t->hlen + sizeof(struct ipv6hdr); 1858 1859 dev->type = ARPHRD_TUNNEL6; 1860 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1861 dev->mtu = ETH_DATA_LEN - t_hlen; 1862 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1863 dev->mtu -= 8; 1864 dev->min_mtu = ETH_MIN_MTU; 1865 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len; 1866 1867 return 0; 1868 1869 destroy_dst: 1870 dst_cache_destroy(&t->dst_cache); 1871 free_stats: 1872 free_percpu(dev->tstats); 1873 dev->tstats = NULL; 1874 1875 return ret; 1876 } 1877 1878 /** 1879 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1880 * @dev: virtual device associated with tunnel 1881 **/ 1882 1883 static int ip6_tnl_dev_init(struct net_device *dev) 1884 { 1885 struct ip6_tnl *t = netdev_priv(dev); 1886 int err = ip6_tnl_dev_init_gen(dev); 1887 1888 if (err) 1889 return err; 1890 ip6_tnl_link_config(t); 1891 if (t->parms.collect_md) { 1892 dev->features |= NETIF_F_NETNS_LOCAL; 1893 netif_keep_dst(dev); 1894 } 1895 return 0; 1896 } 1897 1898 /** 1899 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1900 * @dev: fallback device 1901 * 1902 * Return: 0 1903 **/ 1904 1905 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1906 { 1907 struct ip6_tnl *t = netdev_priv(dev); 1908 struct net *net = dev_net(dev); 1909 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1910 1911 t->parms.proto = IPPROTO_IPV6; 1912 dev_hold(dev); 1913 1914 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1915 return 0; 1916 } 1917 1918 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[], 1919 struct netlink_ext_ack *extack) 1920 { 1921 u8 proto; 1922 1923 if (!data || !data[IFLA_IPTUN_PROTO]) 1924 return 0; 1925 1926 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1927 if (proto != IPPROTO_IPV6 && 1928 proto != IPPROTO_IPIP && 1929 proto != 0) 1930 return -EINVAL; 1931 1932 return 0; 1933 } 1934 1935 static void ip6_tnl_netlink_parms(struct nlattr *data[], 1936 struct __ip6_tnl_parm *parms) 1937 { 1938 memset(parms, 0, sizeof(*parms)); 1939 1940 if (!data) 1941 return; 1942 1943 if (data[IFLA_IPTUN_LINK]) 1944 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1945 1946 if (data[IFLA_IPTUN_LOCAL]) 1947 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]); 1948 1949 if (data[IFLA_IPTUN_REMOTE]) 1950 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]); 1951 1952 if (data[IFLA_IPTUN_TTL]) 1953 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); 1954 1955 if (data[IFLA_IPTUN_ENCAP_LIMIT]) 1956 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); 1957 1958 if (data[IFLA_IPTUN_FLOWINFO]) 1959 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); 1960 1961 if (data[IFLA_IPTUN_FLAGS]) 1962 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); 1963 1964 if (data[IFLA_IPTUN_PROTO]) 1965 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1966 1967 if (data[IFLA_IPTUN_COLLECT_METADATA]) 1968 parms->collect_md = true; 1969 1970 if (data[IFLA_IPTUN_FWMARK]) 1971 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 1972 } 1973 1974 static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[], 1975 struct ip_tunnel_encap *ipencap) 1976 { 1977 bool ret = false; 1978 1979 memset(ipencap, 0, sizeof(*ipencap)); 1980 1981 if (!data) 1982 return ret; 1983 1984 if (data[IFLA_IPTUN_ENCAP_TYPE]) { 1985 ret = true; 1986 ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]); 1987 } 1988 1989 if (data[IFLA_IPTUN_ENCAP_FLAGS]) { 1990 ret = true; 1991 ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]); 1992 } 1993 1994 if (data[IFLA_IPTUN_ENCAP_SPORT]) { 1995 ret = true; 1996 ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]); 1997 } 1998 1999 if (data[IFLA_IPTUN_ENCAP_DPORT]) { 2000 ret = true; 2001 ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]); 2002 } 2003 2004 return ret; 2005 } 2006 2007 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, 2008 struct nlattr *tb[], struct nlattr *data[], 2009 struct netlink_ext_ack *extack) 2010 { 2011 struct net *net = dev_net(dev); 2012 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2013 struct ip_tunnel_encap ipencap; 2014 struct ip6_tnl *nt, *t; 2015 int err; 2016 2017 nt = netdev_priv(dev); 2018 2019 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2020 err = ip6_tnl_encap_setup(nt, &ipencap); 2021 if (err < 0) 2022 return err; 2023 } 2024 2025 ip6_tnl_netlink_parms(data, &nt->parms); 2026 2027 if (nt->parms.collect_md) { 2028 if (rtnl_dereference(ip6n->collect_md_tun)) 2029 return -EEXIST; 2030 } else { 2031 t = ip6_tnl_locate(net, &nt->parms, 0); 2032 if (!IS_ERR(t)) 2033 return -EEXIST; 2034 } 2035 2036 err = ip6_tnl_create2(dev); 2037 if (!err && tb[IFLA_MTU]) 2038 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 2039 2040 return err; 2041 } 2042 2043 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], 2044 struct nlattr *data[], 2045 struct netlink_ext_ack *extack) 2046 { 2047 struct ip6_tnl *t = netdev_priv(dev); 2048 struct __ip6_tnl_parm p; 2049 struct net *net = t->net; 2050 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2051 struct ip_tunnel_encap ipencap; 2052 2053 if (dev == ip6n->fb_tnl_dev) 2054 return -EINVAL; 2055 2056 if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { 2057 int err = ip6_tnl_encap_setup(t, &ipencap); 2058 2059 if (err < 0) 2060 return err; 2061 } 2062 ip6_tnl_netlink_parms(data, &p); 2063 if (p.collect_md) 2064 return -EINVAL; 2065 2066 t = ip6_tnl_locate(net, &p, 0); 2067 if (!IS_ERR(t)) { 2068 if (t->dev != dev) 2069 return -EEXIST; 2070 } else 2071 t = netdev_priv(dev); 2072 2073 return ip6_tnl_update(t, &p); 2074 } 2075 2076 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head) 2077 { 2078 struct net *net = dev_net(dev); 2079 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2080 2081 if (dev != ip6n->fb_tnl_dev) 2082 unregister_netdevice_queue(dev, head); 2083 } 2084 2085 static size_t ip6_tnl_get_size(const struct net_device *dev) 2086 { 2087 return 2088 /* IFLA_IPTUN_LINK */ 2089 nla_total_size(4) + 2090 /* IFLA_IPTUN_LOCAL */ 2091 nla_total_size(sizeof(struct in6_addr)) + 2092 /* IFLA_IPTUN_REMOTE */ 2093 nla_total_size(sizeof(struct in6_addr)) + 2094 /* IFLA_IPTUN_TTL */ 2095 nla_total_size(1) + 2096 /* IFLA_IPTUN_ENCAP_LIMIT */ 2097 nla_total_size(1) + 2098 /* IFLA_IPTUN_FLOWINFO */ 2099 nla_total_size(4) + 2100 /* IFLA_IPTUN_FLAGS */ 2101 nla_total_size(4) + 2102 /* IFLA_IPTUN_PROTO */ 2103 nla_total_size(1) + 2104 /* IFLA_IPTUN_ENCAP_TYPE */ 2105 nla_total_size(2) + 2106 /* IFLA_IPTUN_ENCAP_FLAGS */ 2107 nla_total_size(2) + 2108 /* IFLA_IPTUN_ENCAP_SPORT */ 2109 nla_total_size(2) + 2110 /* IFLA_IPTUN_ENCAP_DPORT */ 2111 nla_total_size(2) + 2112 /* IFLA_IPTUN_COLLECT_METADATA */ 2113 nla_total_size(0) + 2114 /* IFLA_IPTUN_FWMARK */ 2115 nla_total_size(4) + 2116 0; 2117 } 2118 2119 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) 2120 { 2121 struct ip6_tnl *tunnel = netdev_priv(dev); 2122 struct __ip6_tnl_parm *parm = &tunnel->parms; 2123 2124 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 2125 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) || 2126 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) || 2127 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || 2128 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || 2129 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || 2130 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || 2131 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) || 2132 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark)) 2133 goto nla_put_failure; 2134 2135 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) || 2136 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) || 2137 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) || 2138 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags)) 2139 goto nla_put_failure; 2140 2141 if (parm->collect_md) 2142 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 2143 goto nla_put_failure; 2144 2145 return 0; 2146 2147 nla_put_failure: 2148 return -EMSGSIZE; 2149 } 2150 2151 struct net *ip6_tnl_get_link_net(const struct net_device *dev) 2152 { 2153 struct ip6_tnl *tunnel = netdev_priv(dev); 2154 2155 return tunnel->net; 2156 } 2157 EXPORT_SYMBOL(ip6_tnl_get_link_net); 2158 2159 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { 2160 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 2161 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, 2162 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, 2163 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 2164 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, 2165 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, 2166 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, 2167 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 2168 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 2169 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 2170 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 2171 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 2172 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 2173 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 2174 }; 2175 2176 static struct rtnl_link_ops ip6_link_ops __read_mostly = { 2177 .kind = "ip6tnl", 2178 .maxtype = IFLA_IPTUN_MAX, 2179 .policy = ip6_tnl_policy, 2180 .priv_size = sizeof(struct ip6_tnl), 2181 .setup = ip6_tnl_dev_setup, 2182 .validate = ip6_tnl_validate, 2183 .newlink = ip6_tnl_newlink, 2184 .changelink = ip6_tnl_changelink, 2185 .dellink = ip6_tnl_dellink, 2186 .get_size = ip6_tnl_get_size, 2187 .fill_info = ip6_tnl_fill_info, 2188 .get_link_net = ip6_tnl_get_link_net, 2189 }; 2190 2191 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 2192 .handler = ip4ip6_rcv, 2193 .err_handler = ip4ip6_err, 2194 .priority = 1, 2195 }; 2196 2197 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 2198 .handler = ip6ip6_rcv, 2199 .err_handler = ip6ip6_err, 2200 .priority = 1, 2201 }; 2202 2203 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list) 2204 { 2205 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2206 struct net_device *dev, *aux; 2207 int h; 2208 struct ip6_tnl *t; 2209 2210 for_each_netdev_safe(net, dev, aux) 2211 if (dev->rtnl_link_ops == &ip6_link_ops) 2212 unregister_netdevice_queue(dev, list); 2213 2214 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) { 2215 t = rtnl_dereference(ip6n->tnls_r_l[h]); 2216 while (t) { 2217 /* If dev is in the same netns, it has already 2218 * been added to the list by the previous loop. 2219 */ 2220 if (!net_eq(dev_net(t->dev), net)) 2221 unregister_netdevice_queue(t->dev, list); 2222 t = rtnl_dereference(t->next); 2223 } 2224 } 2225 } 2226 2227 static int __net_init ip6_tnl_init_net(struct net *net) 2228 { 2229 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 2230 struct ip6_tnl *t = NULL; 2231 int err; 2232 2233 ip6n->tnls[0] = ip6n->tnls_wc; 2234 ip6n->tnls[1] = ip6n->tnls_r_l; 2235 2236 if (!net_has_fallback_tunnels(net)) 2237 return 0; 2238 err = -ENOMEM; 2239 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 2240 NET_NAME_UNKNOWN, ip6_tnl_dev_setup); 2241 2242 if (!ip6n->fb_tnl_dev) 2243 goto err_alloc_dev; 2244 dev_net_set(ip6n->fb_tnl_dev, net); 2245 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; 2246 /* FB netdevice is special: we have one, and only one per netns. 2247 * Allowing to move it to another netns is clearly unsafe. 2248 */ 2249 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; 2250 2251 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 2252 if (err < 0) 2253 goto err_register; 2254 2255 err = register_netdev(ip6n->fb_tnl_dev); 2256 if (err < 0) 2257 goto err_register; 2258 2259 t = netdev_priv(ip6n->fb_tnl_dev); 2260 2261 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 2262 return 0; 2263 2264 err_register: 2265 free_netdev(ip6n->fb_tnl_dev); 2266 err_alloc_dev: 2267 return err; 2268 } 2269 2270 static void __net_exit ip6_tnl_exit_batch_net(struct list_head *net_list) 2271 { 2272 struct net *net; 2273 LIST_HEAD(list); 2274 2275 rtnl_lock(); 2276 list_for_each_entry(net, net_list, exit_list) 2277 ip6_tnl_destroy_tunnels(net, &list); 2278 unregister_netdevice_many(&list); 2279 rtnl_unlock(); 2280 } 2281 2282 static struct pernet_operations ip6_tnl_net_ops = { 2283 .init = ip6_tnl_init_net, 2284 .exit_batch = ip6_tnl_exit_batch_net, 2285 .id = &ip6_tnl_net_id, 2286 .size = sizeof(struct ip6_tnl_net), 2287 }; 2288 2289 /** 2290 * ip6_tunnel_init - register protocol and reserve needed resources 2291 * 2292 * Return: 0 on success 2293 **/ 2294 2295 static int __init ip6_tunnel_init(void) 2296 { 2297 int err; 2298 2299 if (!ipv6_mod_enabled()) 2300 return -EOPNOTSUPP; 2301 2302 err = register_pernet_device(&ip6_tnl_net_ops); 2303 if (err < 0) 2304 goto out_pernet; 2305 2306 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 2307 if (err < 0) { 2308 pr_err("%s: can't register ip4ip6\n", __func__); 2309 goto out_ip4ip6; 2310 } 2311 2312 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 2313 if (err < 0) { 2314 pr_err("%s: can't register ip6ip6\n", __func__); 2315 goto out_ip6ip6; 2316 } 2317 err = rtnl_link_register(&ip6_link_ops); 2318 if (err < 0) 2319 goto rtnl_link_failed; 2320 2321 return 0; 2322 2323 rtnl_link_failed: 2324 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 2325 out_ip6ip6: 2326 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 2327 out_ip4ip6: 2328 unregister_pernet_device(&ip6_tnl_net_ops); 2329 out_pernet: 2330 return err; 2331 } 2332 2333 /** 2334 * ip6_tunnel_cleanup - free resources and unregister protocol 2335 **/ 2336 2337 static void __exit ip6_tunnel_cleanup(void) 2338 { 2339 rtnl_link_unregister(&ip6_link_ops); 2340 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 2341 pr_info("%s: can't deregister ip4ip6\n", __func__); 2342 2343 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 2344 pr_info("%s: can't deregister ip6ip6\n", __func__); 2345 2346 unregister_pernet_device(&ip6_tnl_net_ops); 2347 } 2348 2349 module_init(ip6_tunnel_init); 2350 module_exit(ip6_tunnel_cleanup); 2351