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_assign_pointer(t->next , rtnl_dereference(*tp)); 222 rcu_assign_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_assign_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_assign_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; 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 ((dst = ip6_tnl_dst_check(t)) != NULL) 901 dst_hold(dst); 902 else { 903 dst = ip6_route_output(net, NULL, fl6); 904 905 if (dst->error) 906 goto tx_err_link_failure; 907 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 908 if (IS_ERR(dst)) { 909 err = PTR_ERR(dst); 910 dst = NULL; 911 goto tx_err_link_failure; 912 } 913 } 914 915 tdev = dst->dev; 916 917 if (tdev == dev) { 918 stats->collisions++; 919 if (net_ratelimit()) 920 printk(KERN_WARNING 921 "%s: Local routing loop detected!\n", 922 t->parms.name); 923 goto tx_err_dst_release; 924 } 925 mtu = dst_mtu(dst) - sizeof (*ipv6h); 926 if (encap_limit >= 0) { 927 max_headroom += 8; 928 mtu -= 8; 929 } 930 if (mtu < IPV6_MIN_MTU) 931 mtu = IPV6_MIN_MTU; 932 if (skb_dst(skb)) 933 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu); 934 if (skb->len > mtu) { 935 *pmtu = mtu; 936 err = -EMSGSIZE; 937 goto tx_err_dst_release; 938 } 939 940 /* 941 * Okay, now see if we can stuff it in the buffer as-is. 942 */ 943 max_headroom += LL_RESERVED_SPACE(tdev); 944 945 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 946 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 947 struct sk_buff *new_skb; 948 949 if (!(new_skb = skb_realloc_headroom(skb, max_headroom))) 950 goto tx_err_dst_release; 951 952 if (skb->sk) 953 skb_set_owner_w(new_skb, skb->sk); 954 kfree_skb(skb); 955 skb = new_skb; 956 } 957 skb_dst_drop(skb); 958 skb_dst_set(skb, dst_clone(dst)); 959 960 skb->transport_header = skb->network_header; 961 962 proto = fl6->flowi6_proto; 963 if (encap_limit >= 0) { 964 init_tel_txopt(&opt, encap_limit); 965 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 966 } 967 skb_push(skb, sizeof(struct ipv6hdr)); 968 skb_reset_network_header(skb); 969 ipv6h = ipv6_hdr(skb); 970 *(__be32*)ipv6h = fl6->flowlabel | htonl(0x60000000); 971 dsfield = INET_ECN_encapsulate(0, dsfield); 972 ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield); 973 ipv6h->hop_limit = t->parms.hop_limit; 974 ipv6h->nexthdr = proto; 975 ipv6_addr_copy(&ipv6h->saddr, &fl6->saddr); 976 ipv6_addr_copy(&ipv6h->daddr, &fl6->daddr); 977 nf_reset(skb); 978 pkt_len = skb->len; 979 err = ip6_local_out(skb); 980 981 if (net_xmit_eval(err) == 0) { 982 struct pcpu_tstats *tstats = this_cpu_ptr(t->dev->tstats); 983 984 tstats->tx_bytes += pkt_len; 985 tstats->tx_packets++; 986 } else { 987 stats->tx_errors++; 988 stats->tx_aborted_errors++; 989 } 990 ip6_tnl_dst_store(t, dst); 991 return 0; 992 tx_err_link_failure: 993 stats->tx_carrier_errors++; 994 dst_link_failure(skb); 995 tx_err_dst_release: 996 dst_release(dst); 997 return err; 998 } 999 1000 static inline int 1001 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1002 { 1003 struct ip6_tnl *t = netdev_priv(dev); 1004 const struct iphdr *iph = ip_hdr(skb); 1005 int encap_limit = -1; 1006 struct flowi6 fl6; 1007 __u8 dsfield; 1008 __u32 mtu; 1009 int err; 1010 1011 if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) || 1012 !ip6_tnl_xmit_ctl(t)) 1013 return -1; 1014 1015 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1016 encap_limit = t->parms.encap_limit; 1017 1018 memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6)); 1019 fl6.flowi6_proto = IPPROTO_IPIP; 1020 1021 dsfield = ipv4_get_dsfield(iph); 1022 1023 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 1024 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 1025 & IPV6_TCLASS_MASK; 1026 1027 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 1028 if (err != 0) { 1029 /* XXX: send ICMP error even if DF is not set. */ 1030 if (err == -EMSGSIZE) 1031 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 1032 htonl(mtu)); 1033 return -1; 1034 } 1035 1036 return 0; 1037 } 1038 1039 static inline int 1040 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1041 { 1042 struct ip6_tnl *t = netdev_priv(dev); 1043 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 1044 int encap_limit = -1; 1045 __u16 offset; 1046 struct flowi6 fl6; 1047 __u8 dsfield; 1048 __u32 mtu; 1049 int err; 1050 1051 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 1052 !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h)) 1053 return -1; 1054 1055 offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb)); 1056 if (offset > 0) { 1057 struct ipv6_tlv_tnl_enc_lim *tel; 1058 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 1059 if (tel->encap_limit == 0) { 1060 icmpv6_send(skb, ICMPV6_PARAMPROB, 1061 ICMPV6_HDR_FIELD, offset + 2); 1062 return -1; 1063 } 1064 encap_limit = tel->encap_limit - 1; 1065 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1066 encap_limit = t->parms.encap_limit; 1067 1068 memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6)); 1069 fl6.flowi6_proto = IPPROTO_IPV6; 1070 1071 dsfield = ipv6_get_dsfield(ipv6h); 1072 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 1073 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 1074 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1075 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 1076 1077 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 1078 if (err != 0) { 1079 if (err == -EMSGSIZE) 1080 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 1081 return -1; 1082 } 1083 1084 return 0; 1085 } 1086 1087 static netdev_tx_t 1088 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1089 { 1090 struct ip6_tnl *t = netdev_priv(dev); 1091 struct net_device_stats *stats = &t->dev->stats; 1092 int ret; 1093 1094 switch (skb->protocol) { 1095 case htons(ETH_P_IP): 1096 ret = ip4ip6_tnl_xmit(skb, dev); 1097 break; 1098 case htons(ETH_P_IPV6): 1099 ret = ip6ip6_tnl_xmit(skb, dev); 1100 break; 1101 default: 1102 goto tx_err; 1103 } 1104 1105 if (ret < 0) 1106 goto tx_err; 1107 1108 return NETDEV_TX_OK; 1109 1110 tx_err: 1111 stats->tx_errors++; 1112 stats->tx_dropped++; 1113 kfree_skb(skb); 1114 return NETDEV_TX_OK; 1115 } 1116 1117 static void ip6_tnl_set_cap(struct ip6_tnl *t) 1118 { 1119 struct ip6_tnl_parm *p = &t->parms; 1120 int ltype = ipv6_addr_type(&p->laddr); 1121 int rtype = ipv6_addr_type(&p->raddr); 1122 1123 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV); 1124 1125 if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1126 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1127 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 1128 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 1129 if (ltype&IPV6_ADDR_UNICAST) 1130 p->flags |= IP6_TNL_F_CAP_XMIT; 1131 if (rtype&IPV6_ADDR_UNICAST) 1132 p->flags |= IP6_TNL_F_CAP_RCV; 1133 } 1134 } 1135 1136 static void ip6_tnl_link_config(struct ip6_tnl *t) 1137 { 1138 struct net_device *dev = t->dev; 1139 struct ip6_tnl_parm *p = &t->parms; 1140 struct flowi6 *fl6 = &t->fl.u.ip6; 1141 1142 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1143 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1144 1145 /* Set up flowi template */ 1146 ipv6_addr_copy(&fl6->saddr, &p->laddr); 1147 ipv6_addr_copy(&fl6->daddr, &p->raddr); 1148 fl6->flowi6_oif = p->link; 1149 fl6->flowlabel = 0; 1150 1151 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1152 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1153 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1154 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1155 1156 ip6_tnl_set_cap(t); 1157 1158 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1159 dev->flags |= IFF_POINTOPOINT; 1160 else 1161 dev->flags &= ~IFF_POINTOPOINT; 1162 1163 dev->iflink = p->link; 1164 1165 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1166 int strict = (ipv6_addr_type(&p->raddr) & 1167 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1168 1169 struct rt6_info *rt = rt6_lookup(dev_net(dev), 1170 &p->raddr, &p->laddr, 1171 p->link, strict); 1172 1173 if (rt == NULL) 1174 return; 1175 1176 if (rt->rt6i_dev) { 1177 dev->hard_header_len = rt->rt6i_dev->hard_header_len + 1178 sizeof (struct ipv6hdr); 1179 1180 dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr); 1181 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1182 dev->mtu-=8; 1183 1184 if (dev->mtu < IPV6_MIN_MTU) 1185 dev->mtu = IPV6_MIN_MTU; 1186 } 1187 dst_release(&rt->dst); 1188 } 1189 } 1190 1191 /** 1192 * ip6_tnl_change - update the tunnel parameters 1193 * @t: tunnel to be changed 1194 * @p: tunnel configuration parameters 1195 * 1196 * Description: 1197 * ip6_tnl_change() updates the tunnel parameters 1198 **/ 1199 1200 static int 1201 ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p) 1202 { 1203 ipv6_addr_copy(&t->parms.laddr, &p->laddr); 1204 ipv6_addr_copy(&t->parms.raddr, &p->raddr); 1205 t->parms.flags = p->flags; 1206 t->parms.hop_limit = p->hop_limit; 1207 t->parms.encap_limit = p->encap_limit; 1208 t->parms.flowinfo = p->flowinfo; 1209 t->parms.link = p->link; 1210 t->parms.proto = p->proto; 1211 ip6_tnl_dst_reset(t); 1212 ip6_tnl_link_config(t); 1213 return 0; 1214 } 1215 1216 /** 1217 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1218 * @dev: virtual device associated with tunnel 1219 * @ifr: parameters passed from userspace 1220 * @cmd: command to be performed 1221 * 1222 * Description: 1223 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1224 * from userspace. 1225 * 1226 * The possible commands are the following: 1227 * %SIOCGETTUNNEL: get tunnel parameters for device 1228 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1229 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1230 * %SIOCDELTUNNEL: delete tunnel 1231 * 1232 * The fallback device "ip6tnl0", created during module 1233 * initialization, can be used for creating other tunnel devices. 1234 * 1235 * Return: 1236 * 0 on success, 1237 * %-EFAULT if unable to copy data to or from userspace, 1238 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1239 * %-EINVAL if passed tunnel parameters are invalid, 1240 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1241 * %-ENODEV if attempting to change or delete a nonexisting device 1242 **/ 1243 1244 static int 1245 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1246 { 1247 int err = 0; 1248 struct ip6_tnl_parm p; 1249 struct ip6_tnl *t = NULL; 1250 struct net *net = dev_net(dev); 1251 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1252 1253 switch (cmd) { 1254 case SIOCGETTUNNEL: 1255 if (dev == ip6n->fb_tnl_dev) { 1256 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) { 1257 err = -EFAULT; 1258 break; 1259 } 1260 t = ip6_tnl_locate(net, &p, 0); 1261 } 1262 if (t == NULL) 1263 t = netdev_priv(dev); 1264 memcpy(&p, &t->parms, sizeof (p)); 1265 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) { 1266 err = -EFAULT; 1267 } 1268 break; 1269 case SIOCADDTUNNEL: 1270 case SIOCCHGTUNNEL: 1271 err = -EPERM; 1272 if (!capable(CAP_NET_ADMIN)) 1273 break; 1274 err = -EFAULT; 1275 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1276 break; 1277 err = -EINVAL; 1278 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1279 p.proto != 0) 1280 break; 1281 t = ip6_tnl_locate(net, &p, cmd == SIOCADDTUNNEL); 1282 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 1283 if (t != NULL) { 1284 if (t->dev != dev) { 1285 err = -EEXIST; 1286 break; 1287 } 1288 } else 1289 t = netdev_priv(dev); 1290 1291 ip6_tnl_unlink(ip6n, t); 1292 synchronize_net(); 1293 err = ip6_tnl_change(t, &p); 1294 ip6_tnl_link(ip6n, t); 1295 netdev_state_change(dev); 1296 } 1297 if (t) { 1298 err = 0; 1299 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p))) 1300 err = -EFAULT; 1301 1302 } else 1303 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1304 break; 1305 case SIOCDELTUNNEL: 1306 err = -EPERM; 1307 if (!capable(CAP_NET_ADMIN)) 1308 break; 1309 1310 if (dev == ip6n->fb_tnl_dev) { 1311 err = -EFAULT; 1312 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1313 break; 1314 err = -ENOENT; 1315 if ((t = ip6_tnl_locate(net, &p, 0)) == NULL) 1316 break; 1317 err = -EPERM; 1318 if (t->dev == ip6n->fb_tnl_dev) 1319 break; 1320 dev = t->dev; 1321 } 1322 err = 0; 1323 unregister_netdevice(dev); 1324 break; 1325 default: 1326 err = -EINVAL; 1327 } 1328 return err; 1329 } 1330 1331 /** 1332 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1333 * @dev: virtual device associated with tunnel 1334 * @new_mtu: the new mtu 1335 * 1336 * Return: 1337 * 0 on success, 1338 * %-EINVAL if mtu too small 1339 **/ 1340 1341 static int 1342 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1343 { 1344 if (new_mtu < IPV6_MIN_MTU) { 1345 return -EINVAL; 1346 } 1347 dev->mtu = new_mtu; 1348 return 0; 1349 } 1350 1351 1352 static const struct net_device_ops ip6_tnl_netdev_ops = { 1353 .ndo_uninit = ip6_tnl_dev_uninit, 1354 .ndo_start_xmit = ip6_tnl_xmit, 1355 .ndo_do_ioctl = ip6_tnl_ioctl, 1356 .ndo_change_mtu = ip6_tnl_change_mtu, 1357 .ndo_get_stats = ip6_get_stats, 1358 }; 1359 1360 1361 /** 1362 * ip6_tnl_dev_setup - setup virtual tunnel device 1363 * @dev: virtual device associated with tunnel 1364 * 1365 * Description: 1366 * Initialize function pointers and device parameters 1367 **/ 1368 1369 static void ip6_tnl_dev_setup(struct net_device *dev) 1370 { 1371 struct ip6_tnl *t; 1372 1373 dev->netdev_ops = &ip6_tnl_netdev_ops; 1374 dev->destructor = ip6_dev_free; 1375 1376 dev->type = ARPHRD_TUNNEL6; 1377 dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr); 1378 dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr); 1379 t = netdev_priv(dev); 1380 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1381 dev->mtu-=8; 1382 dev->flags |= IFF_NOARP; 1383 dev->addr_len = sizeof(struct in6_addr); 1384 dev->features |= NETIF_F_NETNS_LOCAL; 1385 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1386 } 1387 1388 1389 /** 1390 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1391 * @dev: virtual device associated with tunnel 1392 **/ 1393 1394 static inline int 1395 ip6_tnl_dev_init_gen(struct net_device *dev) 1396 { 1397 struct ip6_tnl *t = netdev_priv(dev); 1398 1399 t->dev = dev; 1400 strcpy(t->parms.name, dev->name); 1401 dev->tstats = alloc_percpu(struct pcpu_tstats); 1402 if (!dev->tstats) 1403 return -ENOMEM; 1404 return 0; 1405 } 1406 1407 /** 1408 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1409 * @dev: virtual device associated with tunnel 1410 **/ 1411 1412 static int ip6_tnl_dev_init(struct net_device *dev) 1413 { 1414 struct ip6_tnl *t = netdev_priv(dev); 1415 int err = ip6_tnl_dev_init_gen(dev); 1416 1417 if (err) 1418 return err; 1419 ip6_tnl_link_config(t); 1420 return 0; 1421 } 1422 1423 /** 1424 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1425 * @dev: fallback device 1426 * 1427 * Return: 0 1428 **/ 1429 1430 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) 1431 { 1432 struct ip6_tnl *t = netdev_priv(dev); 1433 struct net *net = dev_net(dev); 1434 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1435 int err = ip6_tnl_dev_init_gen(dev); 1436 1437 if (err) 1438 return err; 1439 1440 t->parms.proto = IPPROTO_IPV6; 1441 dev_hold(dev); 1442 rcu_assign_pointer(ip6n->tnls_wc[0], t); 1443 return 0; 1444 } 1445 1446 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { 1447 .handler = ip4ip6_rcv, 1448 .err_handler = ip4ip6_err, 1449 .priority = 1, 1450 }; 1451 1452 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { 1453 .handler = ip6ip6_rcv, 1454 .err_handler = ip6ip6_err, 1455 .priority = 1, 1456 }; 1457 1458 static void __net_exit ip6_tnl_destroy_tunnels(struct ip6_tnl_net *ip6n) 1459 { 1460 int h; 1461 struct ip6_tnl *t; 1462 LIST_HEAD(list); 1463 1464 for (h = 0; h < HASH_SIZE; h++) { 1465 t = rtnl_dereference(ip6n->tnls_r_l[h]); 1466 while (t != NULL) { 1467 unregister_netdevice_queue(t->dev, &list); 1468 t = rtnl_dereference(t->next); 1469 } 1470 } 1471 1472 t = rtnl_dereference(ip6n->tnls_wc[0]); 1473 unregister_netdevice_queue(t->dev, &list); 1474 unregister_netdevice_many(&list); 1475 } 1476 1477 static int __net_init ip6_tnl_init_net(struct net *net) 1478 { 1479 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1480 int err; 1481 1482 ip6n->tnls[0] = ip6n->tnls_wc; 1483 ip6n->tnls[1] = ip6n->tnls_r_l; 1484 1485 err = -ENOMEM; 1486 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 1487 ip6_tnl_dev_setup); 1488 1489 if (!ip6n->fb_tnl_dev) 1490 goto err_alloc_dev; 1491 dev_net_set(ip6n->fb_tnl_dev, net); 1492 1493 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 1494 if (err < 0) 1495 goto err_register; 1496 1497 err = register_netdev(ip6n->fb_tnl_dev); 1498 if (err < 0) 1499 goto err_register; 1500 return 0; 1501 1502 err_register: 1503 ip6_dev_free(ip6n->fb_tnl_dev); 1504 err_alloc_dev: 1505 return err; 1506 } 1507 1508 static void __net_exit ip6_tnl_exit_net(struct net *net) 1509 { 1510 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1511 1512 rtnl_lock(); 1513 ip6_tnl_destroy_tunnels(ip6n); 1514 rtnl_unlock(); 1515 } 1516 1517 static struct pernet_operations ip6_tnl_net_ops = { 1518 .init = ip6_tnl_init_net, 1519 .exit = ip6_tnl_exit_net, 1520 .id = &ip6_tnl_net_id, 1521 .size = sizeof(struct ip6_tnl_net), 1522 }; 1523 1524 /** 1525 * ip6_tunnel_init - register protocol and reserve needed resources 1526 * 1527 * Return: 0 on success 1528 **/ 1529 1530 static int __init ip6_tunnel_init(void) 1531 { 1532 int err; 1533 1534 err = register_pernet_device(&ip6_tnl_net_ops); 1535 if (err < 0) 1536 goto out_pernet; 1537 1538 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); 1539 if (err < 0) { 1540 printk(KERN_ERR "ip6_tunnel init: can't register ip4ip6\n"); 1541 goto out_ip4ip6; 1542 } 1543 1544 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); 1545 if (err < 0) { 1546 printk(KERN_ERR "ip6_tunnel init: can't register ip6ip6\n"); 1547 goto out_ip6ip6; 1548 } 1549 1550 return 0; 1551 1552 out_ip6ip6: 1553 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 1554 out_ip4ip6: 1555 unregister_pernet_device(&ip6_tnl_net_ops); 1556 out_pernet: 1557 return err; 1558 } 1559 1560 /** 1561 * ip6_tunnel_cleanup - free resources and unregister protocol 1562 **/ 1563 1564 static void __exit ip6_tunnel_cleanup(void) 1565 { 1566 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 1567 printk(KERN_INFO "ip6_tunnel close: can't deregister ip4ip6\n"); 1568 1569 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 1570 printk(KERN_INFO "ip6_tunnel close: can't deregister ip6ip6\n"); 1571 1572 unregister_pernet_device(&ip6_tnl_net_ops); 1573 } 1574 1575 module_init(ip6_tunnel_init); 1576 module_exit(ip6_tunnel_cleanup); 1577