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 #include <linux/module.h> 22 #include <linux/capability.h> 23 #include <linux/errno.h> 24 #include <linux/types.h> 25 #include <linux/sockios.h> 26 #include <linux/icmp.h> 27 #include <linux/if.h> 28 #include <linux/in.h> 29 #include <linux/ip.h> 30 #include <linux/if_tunnel.h> 31 #include <linux/net.h> 32 #include <linux/in6.h> 33 #include <linux/netdevice.h> 34 #include <linux/if_arp.h> 35 #include <linux/icmpv6.h> 36 #include <linux/init.h> 37 #include <linux/route.h> 38 #include <linux/rtnetlink.h> 39 #include <linux/netfilter_ipv6.h> 40 #include <linux/slab.h> 41 42 #include <asm/uaccess.h> 43 #include <linux/atomic.h> 44 45 #include <net/icmp.h> 46 #include <net/ip.h> 47 #include <net/ipv6.h> 48 #include <net/ip6_route.h> 49 #include <net/addrconf.h> 50 #include <net/ip6_tunnel.h> 51 #include <net/xfrm.h> 52 #include <net/dsfield.h> 53 #include <net/inet_ecn.h> 54 #include <net/net_namespace.h> 55 #include <net/netns/generic.h> 56 57 MODULE_AUTHOR("Ville Nuorvala"); 58 MODULE_DESCRIPTION("IPv6 tunneling device"); 59 MODULE_LICENSE("GPL"); 60 MODULE_ALIAS_NETDEV("ip6tnl0"); 61 62 #ifdef IP6_TNL_DEBUG 63 #define IP6_TNL_TRACE(x...) printk(KERN_DEBUG "%s:" x "\n", __func__) 64 #else 65 #define IP6_TNL_TRACE(x...) do {;} while(0) 66 #endif 67 68 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) 69 #define IPV6_TCLASS_SHIFT 20 70 71 #define HASH_SIZE 32 72 73 #define HASH(addr) ((__force u32)((addr)->s6_addr32[0] ^ (addr)->s6_addr32[1] ^ \ 74 (addr)->s6_addr32[2] ^ (addr)->s6_addr32[3]) & \ 75 (HASH_SIZE - 1)) 76 77 static int ip6_tnl_dev_init(struct net_device *dev); 78 static void ip6_tnl_dev_setup(struct net_device *dev); 79 80 static int ip6_tnl_net_id __read_mostly; 81 struct ip6_tnl_net { 82 /* the IPv6 tunnel fallback device */ 83 struct net_device *fb_tnl_dev; 84 /* lists for storing tunnels in use */ 85 struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE]; 86 struct ip6_tnl __rcu *tnls_wc[1]; 87 struct ip6_tnl __rcu **tnls[2]; 88 }; 89 90 /* often modified stats are per cpu, other are shared (netdev->stats) */ 91 struct pcpu_tstats { 92 unsigned long rx_packets; 93 unsigned long rx_bytes; 94 unsigned long tx_packets; 95 unsigned long tx_bytes; 96 }; 97 98 static struct net_device_stats *ip6_get_stats(struct net_device *dev) 99 { 100 struct pcpu_tstats sum = { 0 }; 101 int i; 102 103 for_each_possible_cpu(i) { 104 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i); 105 106 sum.rx_packets += tstats->rx_packets; 107 sum.rx_bytes += tstats->rx_bytes; 108 sum.tx_packets += tstats->tx_packets; 109 sum.tx_bytes += tstats->tx_bytes; 110 } 111 dev->stats.rx_packets = sum.rx_packets; 112 dev->stats.rx_bytes = sum.rx_bytes; 113 dev->stats.tx_packets = sum.tx_packets; 114 dev->stats.tx_bytes = sum.tx_bytes; 115 return &dev->stats; 116 } 117 118 /* 119 * Locking : hash tables are protected by RCU and RTNL 120 */ 121 122 static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t) 123 { 124 struct dst_entry *dst = t->dst_cache; 125 126 if (dst && dst->obsolete && 127 dst->ops->check(dst, t->dst_cookie) == NULL) { 128 t->dst_cache = NULL; 129 dst_release(dst); 130 return NULL; 131 } 132 133 return dst; 134 } 135 136 static inline void ip6_tnl_dst_reset(struct ip6_tnl *t) 137 { 138 dst_release(t->dst_cache); 139 t->dst_cache = NULL; 140 } 141 142 static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst) 143 { 144 struct rt6_info *rt = (struct rt6_info *) dst; 145 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; 146 dst_release(t->dst_cache); 147 t->dst_cache = dst; 148 } 149 150 /** 151 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 152 * @remote: the address of the tunnel exit-point 153 * @local: the address of the tunnel entry-point 154 * 155 * Return: 156 * tunnel matching given end-points if found, 157 * else fallback tunnel if its device is up, 158 * else %NULL 159 **/ 160 161 #define for_each_ip6_tunnel_rcu(start) \ 162 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 163 164 static struct ip6_tnl * 165 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local) 166 { 167 unsigned int h0 = HASH(remote); 168 unsigned int h1 = HASH(local); 169 struct ip6_tnl *t; 170 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 171 172 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[h0 ^ h1]) { 173 if (ipv6_addr_equal(local, &t->parms.laddr) && 174 ipv6_addr_equal(remote, &t->parms.raddr) && 175 (t->dev->flags & IFF_UP)) 176 return t; 177 } 178 t = rcu_dereference(ip6n->tnls_wc[0]); 179 if (t && (t->dev->flags & IFF_UP)) 180 return t; 181 182 return NULL; 183 } 184 185 /** 186 * ip6_tnl_bucket - get head of list matching given tunnel parameters 187 * @p: parameters containing tunnel end-points 188 * 189 * Description: 190 * ip6_tnl_bucket() returns the head of the list matching the 191 * &struct in6_addr entries laddr and raddr in @p. 192 * 193 * Return: head of IPv6 tunnel list 194 **/ 195 196 static struct ip6_tnl __rcu ** 197 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct ip6_tnl_parm *p) 198 { 199 const struct in6_addr *remote = &p->raddr; 200 const struct in6_addr *local = &p->laddr; 201 unsigned h = 0; 202 int prio = 0; 203 204 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 205 prio = 1; 206 h = HASH(remote) ^ HASH(local); 207 } 208 return &ip6n->tnls[prio][h]; 209 } 210 211 /** 212 * ip6_tnl_link - add tunnel to hash table 213 * @t: tunnel to be added 214 **/ 215 216 static void 217 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 218 { 219 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); 220 221 RCU_INIT_POINTER(t->next , rtnl_dereference(*tp)); 222 RCU_INIT_POINTER(*tp, t); 223 } 224 225 /** 226 * ip6_tnl_unlink - remove tunnel from hash table 227 * @t: tunnel to be removed 228 **/ 229 230 static void 231 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 232 { 233 struct ip6_tnl __rcu **tp; 234 struct ip6_tnl *iter; 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_INIT_POINTER(*tp, t->next); 241 break; 242 } 243 } 244 } 245 246 static void ip6_dev_free(struct net_device *dev) 247 { 248 free_percpu(dev->tstats); 249 free_netdev(dev); 250 } 251 252 /** 253 * ip6_tnl_create() - create a new tunnel 254 * @p: tunnel parameters 255 * @pt: pointer to new tunnel 256 * 257 * Description: 258 * Create tunnel matching given parameters. 259 * 260 * Return: 261 * created tunnel or NULL 262 **/ 263 264 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct ip6_tnl_parm *p) 265 { 266 struct net_device *dev; 267 struct ip6_tnl *t; 268 char name[IFNAMSIZ]; 269 int err; 270 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 271 272 if (p->name[0]) 273 strlcpy(name, p->name, IFNAMSIZ); 274 else 275 sprintf(name, "ip6tnl%%d"); 276 277 dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup); 278 if (dev == NULL) 279 goto failed; 280 281 dev_net_set(dev, net); 282 283 t = netdev_priv(dev); 284 t->parms = *p; 285 err = ip6_tnl_dev_init(dev); 286 if (err < 0) 287 goto failed_free; 288 289 if ((err = register_netdevice(dev)) < 0) 290 goto failed_free; 291 292 dev_hold(dev); 293 ip6_tnl_link(ip6n, t); 294 return t; 295 296 failed_free: 297 ip6_dev_free(dev); 298 failed: 299 return NULL; 300 } 301 302 /** 303 * ip6_tnl_locate - find or create tunnel matching given parameters 304 * @p: tunnel parameters 305 * @create: != 0 if allowed to create new tunnel if no match found 306 * 307 * Description: 308 * ip6_tnl_locate() first tries to locate an existing tunnel 309 * based on @parms. If this is unsuccessful, but @create is set a new 310 * tunnel device is created and registered for use. 311 * 312 * Return: 313 * matching tunnel or NULL 314 **/ 315 316 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 317 struct ip6_tnl_parm *p, int create) 318 { 319 const struct in6_addr *remote = &p->raddr; 320 const struct in6_addr *local = &p->laddr; 321 struct ip6_tnl __rcu **tp; 322 struct ip6_tnl *t; 323 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 324 325 for (tp = ip6_tnl_bucket(ip6n, p); 326 (t = rtnl_dereference(*tp)) != NULL; 327 tp = &t->next) { 328 if (ipv6_addr_equal(local, &t->parms.laddr) && 329 ipv6_addr_equal(remote, &t->parms.raddr)) 330 return t; 331 } 332 if (!create) 333 return NULL; 334 return ip6_tnl_create(net, p); 335 } 336 337 /** 338 * ip6_tnl_dev_uninit - tunnel device uninitializer 339 * @dev: the device to be destroyed 340 * 341 * Description: 342 * ip6_tnl_dev_uninit() removes tunnel from its list 343 **/ 344 345 static void 346 ip6_tnl_dev_uninit(struct net_device *dev) 347 { 348 struct ip6_tnl *t = netdev_priv(dev); 349 struct net *net = dev_net(dev); 350 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 351 352 if (dev == ip6n->fb_tnl_dev) 353 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 354 else 355 ip6_tnl_unlink(ip6n, t); 356 ip6_tnl_dst_reset(t); 357 dev_put(dev); 358 } 359 360 /** 361 * parse_tvl_tnl_enc_lim - handle encapsulation limit option 362 * @skb: received socket buffer 363 * 364 * Return: 365 * 0 if none was found, 366 * else index to encapsulation limit 367 **/ 368 369 static __u16 370 parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw) 371 { 372 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw; 373 __u8 nexthdr = ipv6h->nexthdr; 374 __u16 off = sizeof (*ipv6h); 375 376 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 377 __u16 optlen = 0; 378 struct ipv6_opt_hdr *hdr; 379 if (raw + off + sizeof (*hdr) > skb->data && 380 !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr))) 381 break; 382 383 hdr = (struct ipv6_opt_hdr *) (raw + off); 384 if (nexthdr == NEXTHDR_FRAGMENT) { 385 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 386 if (frag_hdr->frag_off) 387 break; 388 optlen = 8; 389 } else if (nexthdr == NEXTHDR_AUTH) { 390 optlen = (hdr->hdrlen + 2) << 2; 391 } else { 392 optlen = ipv6_optlen(hdr); 393 } 394 if (nexthdr == NEXTHDR_DEST) { 395 __u16 i = off + 2; 396 while (1) { 397 struct ipv6_tlv_tnl_enc_lim *tel; 398 399 /* No more room for encapsulation limit */ 400 if (i + sizeof (*tel) > off + optlen) 401 break; 402 403 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i]; 404 /* return index of option if found and valid */ 405 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 406 tel->length == 1) 407 return i; 408 /* else jump to next option */ 409 if (tel->type) 410 i += tel->length + 2; 411 else 412 i++; 413 } 414 } 415 nexthdr = hdr->nexthdr; 416 off += optlen; 417 } 418 return 0; 419 } 420 421 /** 422 * ip6_tnl_err - tunnel error handler 423 * 424 * Description: 425 * ip6_tnl_err() should handle errors in the tunnel according 426 * to the specifications in RFC 2473. 427 **/ 428 429 static int 430 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 431 u8 *type, u8 *code, int *msg, __u32 *info, int offset) 432 { 433 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data; 434 struct ip6_tnl *t; 435 int rel_msg = 0; 436 u8 rel_type = ICMPV6_DEST_UNREACH; 437 u8 rel_code = ICMPV6_ADDR_UNREACH; 438 __u32 rel_info = 0; 439 __u16 len; 440 int err = -ENOENT; 441 442 /* If the packet doesn't contain the original IPv6 header we are 443 in trouble since we might need the source address for further 444 processing of the error. */ 445 446 rcu_read_lock(); 447 if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, 448 &ipv6h->saddr)) == NULL) 449 goto out; 450 451 if (t->parms.proto != ipproto && t->parms.proto != 0) 452 goto out; 453 454 err = 0; 455 456 switch (*type) { 457 __u32 teli; 458 struct ipv6_tlv_tnl_enc_lim *tel; 459 __u32 mtu; 460 case ICMPV6_DEST_UNREACH: 461 if (net_ratelimit()) 462 printk(KERN_WARNING 463 "%s: Path to destination invalid " 464 "or inactive!\n", t->parms.name); 465 rel_msg = 1; 466 break; 467 case ICMPV6_TIME_EXCEED: 468 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 469 if (net_ratelimit()) 470 printk(KERN_WARNING 471 "%s: Too small hop limit or " 472 "routing loop in tunnel!\n", 473 t->parms.name); 474 rel_msg = 1; 475 } 476 break; 477 case ICMPV6_PARAMPROB: 478 teli = 0; 479 if ((*code) == ICMPV6_HDR_FIELD) 480 teli = parse_tlv_tnl_enc_lim(skb, skb->data); 481 482 if (teli && teli == *info - 2) { 483 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 484 if (tel->encap_limit == 0) { 485 if (net_ratelimit()) 486 printk(KERN_WARNING 487 "%s: Too small encapsulation " 488 "limit or routing loop in " 489 "tunnel!\n", t->parms.name); 490 rel_msg = 1; 491 } 492 } else if (net_ratelimit()) { 493 printk(KERN_WARNING 494 "%s: Recipient unable to parse tunneled " 495 "packet!\n ", t->parms.name); 496 } 497 break; 498 case ICMPV6_PKT_TOOBIG: 499 mtu = *info - offset; 500 if (mtu < IPV6_MIN_MTU) 501 mtu = IPV6_MIN_MTU; 502 t->dev->mtu = mtu; 503 504 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) { 505 rel_type = ICMPV6_PKT_TOOBIG; 506 rel_code = 0; 507 rel_info = mtu; 508 rel_msg = 1; 509 } 510 break; 511 } 512 513 *type = rel_type; 514 *code = rel_code; 515 *info = rel_info; 516 *msg = rel_msg; 517 518 out: 519 rcu_read_unlock(); 520 return err; 521 } 522 523 static int 524 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 525 u8 type, u8 code, int offset, __be32 info) 526 { 527 int rel_msg = 0; 528 u8 rel_type = type; 529 u8 rel_code = code; 530 __u32 rel_info = ntohl(info); 531 int err; 532 struct sk_buff *skb2; 533 const struct iphdr *eiph; 534 struct rtable *rt; 535 struct flowi4 fl4; 536 537 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 538 &rel_msg, &rel_info, offset); 539 if (err < 0) 540 return err; 541 542 if (rel_msg == 0) 543 return 0; 544 545 switch (rel_type) { 546 case ICMPV6_DEST_UNREACH: 547 if (rel_code != ICMPV6_ADDR_UNREACH) 548 return 0; 549 rel_type = ICMP_DEST_UNREACH; 550 rel_code = ICMP_HOST_UNREACH; 551 break; 552 case ICMPV6_PKT_TOOBIG: 553 if (rel_code != 0) 554 return 0; 555 rel_type = ICMP_DEST_UNREACH; 556 rel_code = ICMP_FRAG_NEEDED; 557 break; 558 default: 559 return 0; 560 } 561 562 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 563 return 0; 564 565 skb2 = skb_clone(skb, GFP_ATOMIC); 566 if (!skb2) 567 return 0; 568 569 skb_dst_drop(skb2); 570 571 skb_pull(skb2, offset); 572 skb_reset_network_header(skb2); 573 eiph = ip_hdr(skb2); 574 575 /* Try to guess incoming interface */ 576 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 577 eiph->saddr, 0, 578 0, 0, 579 IPPROTO_IPIP, RT_TOS(eiph->tos), 0); 580 if (IS_ERR(rt)) 581 goto out; 582 583 skb2->dev = rt->dst.dev; 584 585 /* route "incoming" packet */ 586 if (rt->rt_flags & RTCF_LOCAL) { 587 ip_rt_put(rt); 588 rt = NULL; 589 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, 590 eiph->daddr, eiph->saddr, 591 0, 0, 592 IPPROTO_IPIP, 593 RT_TOS(eiph->tos), 0); 594 if (IS_ERR(rt) || 595 rt->dst.dev->type != ARPHRD_TUNNEL) { 596 if (!IS_ERR(rt)) 597 ip_rt_put(rt); 598 goto out; 599 } 600 skb_dst_set(skb2, &rt->dst); 601 } else { 602 ip_rt_put(rt); 603 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 604 skb2->dev) || 605 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL) 606 goto out; 607 } 608 609 /* change mtu on this route */ 610 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 611 if (rel_info > dst_mtu(skb_dst(skb2))) 612 goto out; 613 614 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), rel_info); 615 } 616 617 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 618 619 out: 620 kfree_skb(skb2); 621 return 0; 622 } 623 624 static int 625 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 626 u8 type, u8 code, int offset, __be32 info) 627 { 628 int rel_msg = 0; 629 u8 rel_type = type; 630 u8 rel_code = code; 631 __u32 rel_info = ntohl(info); 632 int err; 633 634 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 635 &rel_msg, &rel_info, offset); 636 if (err < 0) 637 return err; 638 639 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 640 struct rt6_info *rt; 641 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 642 643 if (!skb2) 644 return 0; 645 646 skb_dst_drop(skb2); 647 skb_pull(skb2, offset); 648 skb_reset_network_header(skb2); 649 650 /* Try to guess incoming interface */ 651 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 652 NULL, 0, 0); 653 654 if (rt && rt->rt6i_dev) 655 skb2->dev = rt->rt6i_dev; 656 657 icmpv6_send(skb2, rel_type, rel_code, rel_info); 658 659 if (rt) 660 dst_release(&rt->dst); 661 662 kfree_skb(skb2); 663 } 664 665 return 0; 666 } 667 668 static void ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 669 const struct ipv6hdr *ipv6h, 670 struct sk_buff *skb) 671 { 672 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 673 674 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 675 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 676 677 if (INET_ECN_is_ce(dsfield)) 678 IP_ECN_set_ce(ip_hdr(skb)); 679 } 680 681 static void ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, 682 const struct ipv6hdr *ipv6h, 683 struct sk_buff *skb) 684 { 685 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 686 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 687 688 if (INET_ECN_is_ce(ipv6_get_dsfield(ipv6h))) 689 IP6_ECN_set_ce(ipv6_hdr(skb)); 690 } 691 692 /* called with rcu_read_lock() */ 693 static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t) 694 { 695 struct ip6_tnl_parm *p = &t->parms; 696 int ret = 0; 697 struct net *net = dev_net(t->dev); 698 699 if (p->flags & IP6_TNL_F_CAP_RCV) { 700 struct net_device *ldev = NULL; 701 702 if (p->link) 703 ldev = dev_get_by_index_rcu(net, p->link); 704 705 if ((ipv6_addr_is_multicast(&p->laddr) || 706 likely(ipv6_chk_addr(net, &p->laddr, ldev, 0))) && 707 likely(!ipv6_chk_addr(net, &p->raddr, NULL, 0))) 708 ret = 1; 709 710 } 711 return ret; 712 } 713 714 /** 715 * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally 716 * @skb: received socket buffer 717 * @protocol: ethernet protocol ID 718 * @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN 719 * 720 * Return: 0 721 **/ 722 723 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, 724 __u8 ipproto, 725 void (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, 726 const struct ipv6hdr *ipv6h, 727 struct sk_buff *skb)) 728 { 729 struct ip6_tnl *t; 730 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 731 732 rcu_read_lock(); 733 734 if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, 735 &ipv6h->daddr)) != NULL) { 736 struct pcpu_tstats *tstats; 737 738 if (t->parms.proto != ipproto && t->parms.proto != 0) { 739 rcu_read_unlock(); 740 goto discard; 741 } 742 743 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 744 rcu_read_unlock(); 745 goto discard; 746 } 747 748 if (!ip6_tnl_rcv_ctl(t)) { 749 t->dev->stats.rx_dropped++; 750 rcu_read_unlock(); 751 goto discard; 752 } 753 secpath_reset(skb); 754 skb->mac_header = skb->network_header; 755 skb_reset_network_header(skb); 756 skb->protocol = htons(protocol); 757 skb->pkt_type = PACKET_HOST; 758 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 759 760 tstats = this_cpu_ptr(t->dev->tstats); 761 tstats->rx_packets++; 762 tstats->rx_bytes += skb->len; 763 764 __skb_tunnel_rx(skb, t->dev); 765 766 dscp_ecn_decapsulate(t, ipv6h, skb); 767 768 netif_rx(skb); 769 770 rcu_read_unlock(); 771 return 0; 772 } 773 rcu_read_unlock(); 774 return 1; 775 776 discard: 777 kfree_skb(skb); 778 return 0; 779 } 780 781 static int ip4ip6_rcv(struct sk_buff *skb) 782 { 783 return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP, 784 ip4ip6_dscp_ecn_decapsulate); 785 } 786 787 static int ip6ip6_rcv(struct sk_buff *skb) 788 { 789 return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6, 790 ip6ip6_dscp_ecn_decapsulate); 791 } 792 793 struct ipv6_tel_txoption { 794 struct ipv6_txoptions ops; 795 __u8 dst_opt[8]; 796 }; 797 798 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 799 { 800 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 801 802 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 803 opt->dst_opt[3] = 1; 804 opt->dst_opt[4] = encap_limit; 805 opt->dst_opt[5] = IPV6_TLV_PADN; 806 opt->dst_opt[6] = 1; 807 808 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 809 opt->ops.opt_nflen = 8; 810 } 811 812 /** 813 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 814 * @t: the outgoing tunnel device 815 * @hdr: IPv6 header from the incoming packet 816 * 817 * Description: 818 * Avoid trivial tunneling loop by checking that tunnel exit-point 819 * doesn't match source of incoming packet. 820 * 821 * Return: 822 * 1 if conflict, 823 * 0 else 824 **/ 825 826 static inline int 827 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 828 { 829 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 830 } 831 832 static inline int ip6_tnl_xmit_ctl(struct ip6_tnl *t) 833 { 834 struct ip6_tnl_parm *p = &t->parms; 835 int ret = 0; 836 struct net *net = dev_net(t->dev); 837 838 if (p->flags & IP6_TNL_F_CAP_XMIT) { 839 struct net_device *ldev = NULL; 840 841 rcu_read_lock(); 842 if (p->link) 843 ldev = dev_get_by_index_rcu(net, p->link); 844 845 if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0))) 846 printk(KERN_WARNING 847 "%s xmit: Local address not yet configured!\n", 848 p->name); 849 else if (!ipv6_addr_is_multicast(&p->raddr) && 850 unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0))) 851 printk(KERN_WARNING 852 "%s xmit: Routing loop! " 853 "Remote address found on this node!\n", 854 p->name); 855 else 856 ret = 1; 857 rcu_read_unlock(); 858 } 859 return ret; 860 } 861 /** 862 * ip6_tnl_xmit2 - encapsulate packet and send 863 * @skb: the outgoing socket buffer 864 * @dev: the outgoing tunnel device 865 * @dsfield: dscp code for outer header 866 * @fl: flow of tunneled packet 867 * @encap_limit: encapsulation limit 868 * @pmtu: Path MTU is stored if packet is too big 869 * 870 * Description: 871 * Build new header and do some sanity checks on the packet before sending 872 * it. 873 * 874 * Return: 875 * 0 on success 876 * -1 fail 877 * %-EMSGSIZE message too big. return mtu in this case. 878 **/ 879 880 static int ip6_tnl_xmit2(struct sk_buff *skb, 881 struct net_device *dev, 882 __u8 dsfield, 883 struct flowi6 *fl6, 884 int encap_limit, 885 __u32 *pmtu) 886 { 887 struct net *net = dev_net(dev); 888 struct ip6_tnl *t = netdev_priv(dev); 889 struct net_device_stats *stats = &t->dev->stats; 890 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 891 struct ipv6_tel_txoption opt; 892 struct dst_entry *dst = NULL, *ndst = NULL; 893 struct net_device *tdev; 894 int mtu; 895 unsigned int max_headroom = sizeof(struct ipv6hdr); 896 u8 proto; 897 int err = -1; 898 int pkt_len; 899 900 if (!fl6->flowi6_mark) 901 dst = ip6_tnl_dst_check(t); 902 if (!dst) { 903 ndst = ip6_route_output(net, NULL, fl6); 904 905 if (ndst->error) 906 goto tx_err_link_failure; 907 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); 908 if (IS_ERR(ndst)) { 909 err = PTR_ERR(ndst); 910 ndst = NULL; 911 goto tx_err_link_failure; 912 } 913 dst = ndst; 914 } 915 916 tdev = dst->dev; 917 918 if (tdev == dev) { 919 stats->collisions++; 920 if (net_ratelimit()) 921 printk(KERN_WARNING 922 "%s: Local routing loop detected!\n", 923 t->parms.name); 924 goto tx_err_dst_release; 925 } 926 mtu = dst_mtu(dst) - sizeof (*ipv6h); 927 if (encap_limit >= 0) { 928 max_headroom += 8; 929 mtu -= 8; 930 } 931 if (mtu < IPV6_MIN_MTU) 932 mtu = IPV6_MIN_MTU; 933 if (skb_dst(skb)) 934 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu); 935 if (skb->len > mtu) { 936 *pmtu = mtu; 937 err = -EMSGSIZE; 938 goto tx_err_dst_release; 939 } 940 941 /* 942 * Okay, now see if we can stuff it in the buffer as-is. 943 */ 944 max_headroom += LL_RESERVED_SPACE(tdev); 945 946 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 947 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 948 struct sk_buff *new_skb; 949 950 if (!(new_skb = skb_realloc_headroom(skb, max_headroom))) 951 goto tx_err_dst_release; 952 953 if (skb->sk) 954 skb_set_owner_w(new_skb, skb->sk); 955 kfree_skb(skb); 956 skb = new_skb; 957 } 958 skb_dst_drop(skb); 959 if (fl6->flowi6_mark) { 960 skb_dst_set(skb, dst); 961 ndst = NULL; 962 } else { 963 skb_dst_set_noref(skb, dst); 964 } 965 skb->transport_header = skb->network_header; 966 967 proto = fl6->flowi6_proto; 968 if (encap_limit >= 0) { 969 init_tel_txopt(&opt, encap_limit); 970 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 971 } 972 skb_push(skb, sizeof(struct ipv6hdr)); 973 skb_reset_network_header(skb); 974 ipv6h = ipv6_hdr(skb); 975 *(__be32*)ipv6h = fl6->flowlabel | htonl(0x60000000); 976 dsfield = INET_ECN_encapsulate(0, dsfield); 977 ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield); 978 ipv6h->hop_limit = t->parms.hop_limit; 979 ipv6h->nexthdr = proto; 980 ipv6_addr_copy(&ipv6h->saddr, &fl6->saddr); 981 ipv6_addr_copy(&ipv6h->daddr, &fl6->daddr); 982 nf_reset(skb); 983 pkt_len = skb->len; 984 err = ip6_local_out(skb); 985 986 if (net_xmit_eval(err) == 0) { 987 struct pcpu_tstats *tstats = this_cpu_ptr(t->dev->tstats); 988 989 tstats->tx_bytes += pkt_len; 990 tstats->tx_packets++; 991 } else { 992 stats->tx_errors++; 993 stats->tx_aborted_errors++; 994 } 995 if (ndst) 996 ip6_tnl_dst_store(t, ndst); 997 return 0; 998 tx_err_link_failure: 999 stats->tx_carrier_errors++; 1000 dst_link_failure(skb); 1001 tx_err_dst_release: 1002 dst_release(ndst); 1003 return err; 1004 } 1005 1006 static inline int 1007 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1008 { 1009 struct ip6_tnl *t = netdev_priv(dev); 1010 const struct iphdr *iph = ip_hdr(skb); 1011 int encap_limit = -1; 1012 struct flowi6 fl6; 1013 __u8 dsfield; 1014 __u32 mtu; 1015 int err; 1016 1017 if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) || 1018 !ip6_tnl_xmit_ctl(t)) 1019 return -1; 1020 1021 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1022 encap_limit = t->parms.encap_limit; 1023 1024 memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6)); 1025 fl6.flowi6_proto = IPPROTO_IPIP; 1026 1027 dsfield = ipv4_get_dsfield(iph); 1028 1029 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1030 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 1031 & IPV6_TCLASS_MASK; 1032 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1033 fl6.flowi6_mark = skb->mark; 1034 1035 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 1036 if (err != 0) { 1037 /* XXX: send ICMP error even if DF is not set. */ 1038 if (err == -EMSGSIZE) 1039 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 1040 htonl(mtu)); 1041 return -1; 1042 } 1043 1044 return 0; 1045 } 1046 1047 static inline int 1048 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1049 { 1050 struct ip6_tnl *t = netdev_priv(dev); 1051 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 1052 int encap_limit = -1; 1053 __u16 offset; 1054 struct flowi6 fl6; 1055 __u8 dsfield; 1056 __u32 mtu; 1057 int err; 1058 1059 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 1060 !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h)) 1061 return -1; 1062 1063 offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb)); 1064 if (offset > 0) { 1065 struct ipv6_tlv_tnl_enc_lim *tel; 1066 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 1067 if (tel->encap_limit == 0) { 1068 icmpv6_send(skb, ICMPV6_PARAMPROB, 1069 ICMPV6_HDR_FIELD, offset + 2); 1070 return -1; 1071 } 1072 encap_limit = tel->encap_limit - 1; 1073 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1074 encap_limit = t->parms.encap_limit; 1075 1076 memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6)); 1077 fl6.flowi6_proto = IPPROTO_IPV6; 1078 1079 dsfield = ipv6_get_dsfield(ipv6h); 1080 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 1081 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 1082 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 1083 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 1084 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 1085 fl6.flowi6_mark = skb->mark; 1086 1087 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 1088 if (err != 0) { 1089 if (err == -EMSGSIZE) 1090 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1091 return -1; 1092 } 1093 1094 return 0; 1095 } 1096 1097 static netdev_tx_t 1098 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1099 { 1100 struct ip6_tnl *t = netdev_priv(dev); 1101 struct net_device_stats *stats = &t->dev->stats; 1102 int ret; 1103 1104 switch (skb->protocol) { 1105 case htons(ETH_P_IP): 1106 ret = ip4ip6_tnl_xmit(skb, dev); 1107 break; 1108 case htons(ETH_P_IPV6): 1109 ret = ip6ip6_tnl_xmit(skb, dev); 1110 break; 1111 default: 1112 goto tx_err; 1113 } 1114 1115 if (ret < 0) 1116 goto tx_err; 1117 1118 return NETDEV_TX_OK; 1119 1120 tx_err: 1121 stats->tx_errors++; 1122 stats->tx_dropped++; 1123 kfree_skb(skb); 1124 return NETDEV_TX_OK; 1125 } 1126 1127 static void ip6_tnl_set_cap(struct ip6_tnl *t) 1128 { 1129 struct ip6_tnl_parm *p = &t->parms; 1130 int ltype = ipv6_addr_type(&p->laddr); 1131 int rtype = ipv6_addr_type(&p->raddr); 1132 1133 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV); 1134 1135 if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1136 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1137 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 1138 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 1139 if (ltype&IPV6_ADDR_UNICAST) 1140 p->flags |= IP6_TNL_F_CAP_XMIT; 1141 if (rtype&IPV6_ADDR_UNICAST) 1142 p->flags |= IP6_TNL_F_CAP_RCV; 1143 } 1144 } 1145 1146 static void ip6_tnl_link_config(struct ip6_tnl *t) 1147 { 1148 struct net_device *dev = t->dev; 1149 struct ip6_tnl_parm *p = &t->parms; 1150 struct flowi6 *fl6 = &t->fl.u.ip6; 1151 1152 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1153 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1154 1155 /* Set up flowi template */ 1156 ipv6_addr_copy(&fl6->saddr, &p->laddr); 1157 ipv6_addr_copy(&fl6->daddr, &p->raddr); 1158 fl6->flowi6_oif = p->link; 1159 fl6->flowlabel = 0; 1160 1161 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1162 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1163 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1164 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1165 1166 ip6_tnl_set_cap(t); 1167 1168 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1169 dev->flags |= IFF_POINTOPOINT; 1170 else 1171 dev->flags &= ~IFF_POINTOPOINT; 1172 1173 dev->iflink = p->link; 1174 1175 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1176 int strict = (ipv6_addr_type(&p->raddr) & 1177 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1178 1179 struct rt6_info *rt = rt6_lookup(dev_net(dev), 1180 &p->raddr, &p->laddr, 1181 p->link, strict); 1182 1183 if (rt == NULL) 1184 return; 1185 1186 if (rt->rt6i_dev) { 1187 dev->hard_header_len = rt->rt6i_dev->hard_header_len + 1188 sizeof (struct ipv6hdr); 1189 1190 dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr); 1191 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1192 dev->mtu-=8; 1193 1194 if (dev->mtu < IPV6_MIN_MTU) 1195 dev->mtu = IPV6_MIN_MTU; 1196 } 1197 dst_release(&rt->dst); 1198 } 1199 } 1200 1201 /** 1202 * ip6_tnl_change - update the tunnel parameters 1203 * @t: tunnel to be changed 1204 * @p: tunnel configuration parameters 1205 * 1206 * Description: 1207 * ip6_tnl_change() updates the tunnel parameters 1208 **/ 1209 1210 static int 1211 ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p) 1212 { 1213 ipv6_addr_copy(&t->parms.laddr, &p->laddr); 1214 ipv6_addr_copy(&t->parms.raddr, &p->raddr); 1215 t->parms.flags = p->flags; 1216 t->parms.hop_limit = p->hop_limit; 1217 t->parms.encap_limit = p->encap_limit; 1218 t->parms.flowinfo = p->flowinfo; 1219 t->parms.link = p->link; 1220 t->parms.proto = p->proto; 1221 ip6_tnl_dst_reset(t); 1222 ip6_tnl_link_config(t); 1223 return 0; 1224 } 1225 1226 /** 1227 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1228 * @dev: virtual device associated with tunnel 1229 * @ifr: parameters passed from userspace 1230 * @cmd: command to be performed 1231 * 1232 * Description: 1233 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1234 * from userspace. 1235 * 1236 * The possible commands are the following: 1237 * %SIOCGETTUNNEL: get tunnel parameters for device 1238 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1239 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1240 * %SIOCDELTUNNEL: delete tunnel 1241 * 1242 * The fallback device "ip6tnl0", created during module 1243 * initialization, can be used for creating other tunnel devices. 1244 * 1245 * Return: 1246 * 0 on success, 1247 * %-EFAULT if unable to copy data to or from userspace, 1248 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1249 * %-EINVAL if passed tunnel parameters are invalid, 1250 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1251 * %-ENODEV if attempting to change or delete a nonexisting device 1252 **/ 1253 1254 static int 1255 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1256 { 1257 int err = 0; 1258 struct ip6_tnl_parm p; 1259 struct ip6_tnl *t = NULL; 1260 struct net *net = dev_net(dev); 1261 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1262 1263 switch (cmd) { 1264 case SIOCGETTUNNEL: 1265 if (dev == ip6n->fb_tnl_dev) { 1266 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) { 1267 err = -EFAULT; 1268 break; 1269 } 1270 t = ip6_tnl_locate(net, &p, 0); 1271 } 1272 if (t == NULL) 1273 t = netdev_priv(dev); 1274 memcpy(&p, &t->parms, sizeof (p)); 1275 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) { 1276 err = -EFAULT; 1277 } 1278 break; 1279 case SIOCADDTUNNEL: 1280 case SIOCCHGTUNNEL: 1281 err = -EPERM; 1282 if (!capable(CAP_NET_ADMIN)) 1283 break; 1284 err = -EFAULT; 1285 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1286 break; 1287 err = -EINVAL; 1288 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1289 p.proto != 0) 1290 break; 1291 t = ip6_tnl_locate(net, &p, cmd == SIOCADDTUNNEL); 1292 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 1293 if (t != NULL) { 1294 if (t->dev != dev) { 1295 err = -EEXIST; 1296 break; 1297 } 1298 } else 1299 t = netdev_priv(dev); 1300 1301 ip6_tnl_unlink(ip6n, t); 1302 synchronize_net(); 1303 err = ip6_tnl_change(t, &p); 1304 ip6_tnl_link(ip6n, t); 1305 netdev_state_change(dev); 1306 } 1307 if (t) { 1308 err = 0; 1309 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p))) 1310 err = -EFAULT; 1311 1312 } else 1313 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1314 break; 1315 case SIOCDELTUNNEL: 1316 err = -EPERM; 1317 if (!capable(CAP_NET_ADMIN)) 1318 break; 1319 1320 if (dev == ip6n->fb_tnl_dev) { 1321 err = -EFAULT; 1322 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1323 break; 1324 err = -ENOENT; 1325 if ((t = ip6_tnl_locate(net, &p, 0)) == NULL) 1326 break; 1327 err = -EPERM; 1328 if (t->dev == ip6n->fb_tnl_dev) 1329 break; 1330 dev = t->dev; 1331 } 1332 err = 0; 1333 unregister_netdevice(dev); 1334 break; 1335 default: 1336 err = -EINVAL; 1337 } 1338 return err; 1339 } 1340 1341 /** 1342 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1343 * @dev: virtual device associated with tunnel 1344 * @new_mtu: the new mtu 1345 * 1346 * Return: 1347 * 0 on success, 1348 * %-EINVAL if mtu too small 1349 **/ 1350 1351 static int 1352 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1353 { 1354 if (new_mtu < IPV6_MIN_MTU) { 1355 return -EINVAL; 1356 } 1357 dev->mtu = new_mtu; 1358 return 0; 1359 } 1360 1361 1362 static const struct net_device_ops ip6_tnl_netdev_ops = { 1363 .ndo_uninit = ip6_tnl_dev_uninit, 1364 .ndo_start_xmit = ip6_tnl_xmit, 1365 .ndo_do_ioctl = ip6_tnl_ioctl, 1366 .ndo_change_mtu = ip6_tnl_change_mtu, 1367 .ndo_get_stats = ip6_get_stats, 1368 }; 1369 1370 1371 /** 1372 * ip6_tnl_dev_setup - setup virtual tunnel device 1373 * @dev: virtual device associated with tunnel 1374 * 1375 * Description: 1376 * Initialize function pointers and device parameters 1377 **/ 1378 1379 static void ip6_tnl_dev_setup(struct net_device *dev) 1380 { 1381 struct ip6_tnl *t; 1382 1383 dev->netdev_ops = &ip6_tnl_netdev_ops; 1384 dev->destructor = ip6_dev_free; 1385 1386 dev->type = ARPHRD_TUNNEL6; 1387 dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr); 1388 dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr); 1389 t = netdev_priv(dev); 1390 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1391 dev->mtu-=8; 1392 dev->flags |= IFF_NOARP; 1393 dev->addr_len = sizeof(struct in6_addr); 1394 dev->features |= NETIF_F_NETNS_LOCAL; 1395 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1396 } 1397 1398 1399 /** 1400 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1401 * @dev: virtual device associated with tunnel 1402 **/ 1403 1404 static inline int 1405 ip6_tnl_dev_init_gen(struct net_device *dev) 1406 { 1407 struct ip6_tnl *t = netdev_priv(dev); 1408 1409 t->dev = dev; 1410 strcpy(t->parms.name, dev->name); 1411 dev->tstats = alloc_percpu(struct pcpu_tstats); 1412 if (!dev->tstats) 1413 return -ENOMEM; 1414 return 0; 1415 } 1416 1417 /** 1418 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1419 * @dev: virtual device associated with tunnel 1420 **/ 1421 1422 static int ip6_tnl_dev_init(struct net_device *dev) 1423 { 1424 struct ip6_tnl *t = netdev_priv(dev); 1425 int err = ip6_tnl_dev_init_gen(dev); 1426 1427 if (err) 1428 return err; 1429 ip6_tnl_link_config(t); 1430 return 0; 1431 } 1432 1433 /** 1434 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1435 * @dev: fallback device 1436 * 1437 * Return: 0 1438 **/ 1439 1440 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1441 { 1442 struct ip6_tnl *t = netdev_priv(dev); 1443 struct net *net = dev_net(dev); 1444 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1445 int err = ip6_tnl_dev_init_gen(dev); 1446 1447 if (err) 1448 return err; 1449 1450 t->parms.proto = IPPROTO_IPV6; 1451 dev_hold(dev); 1452 RCU_INIT_POINTER(ip6n->tnls_wc[0], t); 1453 return 0; 1454 } 1455 1456 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 1457 .handler = ip4ip6_rcv, 1458 .err_handler = ip4ip6_err, 1459 .priority = 1, 1460 }; 1461 1462 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 1463 .handler = ip6ip6_rcv, 1464 .err_handler = ip6ip6_err, 1465 .priority = 1, 1466 }; 1467 1468 static void __net_exit ip6_tnl_destroy_tunnels(struct ip6_tnl_net *ip6n) 1469 { 1470 int h; 1471 struct ip6_tnl *t; 1472 LIST_HEAD(list); 1473 1474 for (h = 0; h < HASH_SIZE; h++) { 1475 t = rtnl_dereference(ip6n->tnls_r_l[h]); 1476 while (t != NULL) { 1477 unregister_netdevice_queue(t->dev, &list); 1478 t = rtnl_dereference(t->next); 1479 } 1480 } 1481 1482 t = rtnl_dereference(ip6n->tnls_wc[0]); 1483 unregister_netdevice_queue(t->dev, &list); 1484 unregister_netdevice_many(&list); 1485 } 1486 1487 static int __net_init ip6_tnl_init_net(struct net *net) 1488 { 1489 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1490 int err; 1491 1492 ip6n->tnls[0] = ip6n->tnls_wc; 1493 ip6n->tnls[1] = ip6n->tnls_r_l; 1494 1495 err = -ENOMEM; 1496 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 1497 ip6_tnl_dev_setup); 1498 1499 if (!ip6n->fb_tnl_dev) 1500 goto err_alloc_dev; 1501 dev_net_set(ip6n->fb_tnl_dev, net); 1502 1503 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 1504 if (err < 0) 1505 goto err_register; 1506 1507 err = register_netdev(ip6n->fb_tnl_dev); 1508 if (err < 0) 1509 goto err_register; 1510 return 0; 1511 1512 err_register: 1513 ip6_dev_free(ip6n->fb_tnl_dev); 1514 err_alloc_dev: 1515 return err; 1516 } 1517 1518 static void __net_exit ip6_tnl_exit_net(struct net *net) 1519 { 1520 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1521 1522 rtnl_lock(); 1523 ip6_tnl_destroy_tunnels(ip6n); 1524 rtnl_unlock(); 1525 } 1526 1527 static struct pernet_operations ip6_tnl_net_ops = { 1528 .init = ip6_tnl_init_net, 1529 .exit = ip6_tnl_exit_net, 1530 .id = &ip6_tnl_net_id, 1531 .size = sizeof(struct ip6_tnl_net), 1532 }; 1533 1534 /** 1535 * ip6_tunnel_init - register protocol and reserve needed resources 1536 * 1537 * Return: 0 on success 1538 **/ 1539 1540 static int __init ip6_tunnel_init(void) 1541 { 1542 int err; 1543 1544 err = register_pernet_device(&ip6_tnl_net_ops); 1545 if (err < 0) 1546 goto out_pernet; 1547 1548 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 1549 if (err < 0) { 1550 printk(KERN_ERR "ip6_tunnel init: can't register ip4ip6\n"); 1551 goto out_ip4ip6; 1552 } 1553 1554 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 1555 if (err < 0) { 1556 printk(KERN_ERR "ip6_tunnel init: can't register ip6ip6\n"); 1557 goto out_ip6ip6; 1558 } 1559 1560 return 0; 1561 1562 out_ip6ip6: 1563 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 1564 out_ip4ip6: 1565 unregister_pernet_device(&ip6_tnl_net_ops); 1566 out_pernet: 1567 return err; 1568 } 1569 1570 /** 1571 * ip6_tunnel_cleanup - free resources and unregister protocol 1572 **/ 1573 1574 static void __exit ip6_tunnel_cleanup(void) 1575 { 1576 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 1577 printk(KERN_INFO "ip6_tunnel close: can't deregister ip4ip6\n"); 1578 1579 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 1580 printk(KERN_INFO "ip6_tunnel close: can't deregister ip6ip6\n"); 1581 1582 unregister_pernet_device(&ip6_tnl_net_ops); 1583 } 1584 1585 module_init(ip6_tunnel_init); 1586 module_exit(ip6_tunnel_cleanup); 1587