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 * $Id$ 10 * 11 * Based on: 12 * linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c 13 * 14 * RFC 2473 15 * 16 * This program is free software; you can redistribute it and/or 17 * modify it under the terms of the GNU General Public License 18 * as published by the Free Software Foundation; either version 19 * 2 of the License, or (at your option) any later version. 20 * 21 */ 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/if_tunnel.h> 33 #include <linux/net.h> 34 #include <linux/in6.h> 35 #include <linux/netdevice.h> 36 #include <linux/if_arp.h> 37 #include <linux/icmpv6.h> 38 #include <linux/init.h> 39 #include <linux/route.h> 40 #include <linux/rtnetlink.h> 41 #include <linux/netfilter_ipv6.h> 42 43 #include <asm/uaccess.h> 44 #include <asm/atomic.h> 45 46 #include <net/icmp.h> 47 #include <net/ip.h> 48 #include <net/ipv6.h> 49 #include <net/ip6_route.h> 50 #include <net/addrconf.h> 51 #include <net/ip6_tunnel.h> 52 #include <net/xfrm.h> 53 #include <net/dsfield.h> 54 #include <net/inet_ecn.h> 55 56 MODULE_AUTHOR("Ville Nuorvala"); 57 MODULE_DESCRIPTION("IPv6 tunneling device"); 58 MODULE_LICENSE("GPL"); 59 60 #define IPV6_TLV_TEL_DST_SIZE 8 61 62 #ifdef IP6_TNL_DEBUG 63 #define IP6_TNL_TRACE(x...) printk(KERN_DEBUG "%s:" x "\n", __FUNCTION__) 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_fb_tnl_dev_init(struct net_device *dev); 78 static int ip6_tnl_dev_init(struct net_device *dev); 79 static void ip6_tnl_dev_setup(struct net_device *dev); 80 81 /* the IPv6 tunnel fallback device */ 82 static struct net_device *ip6_fb_tnl_dev; 83 84 85 /* lists for storing tunnels in use */ 86 static struct ip6_tnl *tnls_r_l[HASH_SIZE]; 87 static struct ip6_tnl *tnls_wc[1]; 88 static struct ip6_tnl **tnls[2] = { tnls_wc, tnls_r_l }; 89 90 /* lock for the tunnel lists */ 91 static DEFINE_RWLOCK(ip6_tnl_lock); 92 93 static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t) 94 { 95 struct dst_entry *dst = t->dst_cache; 96 97 if (dst && dst->obsolete && 98 dst->ops->check(dst, t->dst_cookie) == NULL) { 99 t->dst_cache = NULL; 100 dst_release(dst); 101 return NULL; 102 } 103 104 return dst; 105 } 106 107 static inline void ip6_tnl_dst_reset(struct ip6_tnl *t) 108 { 109 dst_release(t->dst_cache); 110 t->dst_cache = NULL; 111 } 112 113 static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst) 114 { 115 struct rt6_info *rt = (struct rt6_info *) dst; 116 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; 117 dst_release(t->dst_cache); 118 t->dst_cache = dst; 119 } 120 121 /** 122 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 123 * @remote: the address of the tunnel exit-point 124 * @local: the address of the tunnel entry-point 125 * 126 * Return: 127 * tunnel matching given end-points if found, 128 * else fallback tunnel if its device is up, 129 * else %NULL 130 **/ 131 132 static struct ip6_tnl * 133 ip6_tnl_lookup(struct in6_addr *remote, struct in6_addr *local) 134 { 135 unsigned h0 = HASH(remote); 136 unsigned h1 = HASH(local); 137 struct ip6_tnl *t; 138 139 for (t = tnls_r_l[h0 ^ h1]; t; t = t->next) { 140 if (ipv6_addr_equal(local, &t->parms.laddr) && 141 ipv6_addr_equal(remote, &t->parms.raddr) && 142 (t->dev->flags & IFF_UP)) 143 return t; 144 } 145 if ((t = tnls_wc[0]) != NULL && (t->dev->flags & IFF_UP)) 146 return t; 147 148 return NULL; 149 } 150 151 /** 152 * ip6_tnl_bucket - get head of list matching given tunnel parameters 153 * @p: parameters containing tunnel end-points 154 * 155 * Description: 156 * ip6_tnl_bucket() returns the head of the list matching the 157 * &struct in6_addr entries laddr and raddr in @p. 158 * 159 * Return: head of IPv6 tunnel list 160 **/ 161 162 static struct ip6_tnl ** 163 ip6_tnl_bucket(struct ip6_tnl_parm *p) 164 { 165 struct in6_addr *remote = &p->raddr; 166 struct in6_addr *local = &p->laddr; 167 unsigned h = 0; 168 int prio = 0; 169 170 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 171 prio = 1; 172 h = HASH(remote) ^ HASH(local); 173 } 174 return &tnls[prio][h]; 175 } 176 177 /** 178 * ip6_tnl_link - add tunnel to hash table 179 * @t: tunnel to be added 180 **/ 181 182 static void 183 ip6_tnl_link(struct ip6_tnl *t) 184 { 185 struct ip6_tnl **tp = ip6_tnl_bucket(&t->parms); 186 187 t->next = *tp; 188 write_lock_bh(&ip6_tnl_lock); 189 *tp = t; 190 write_unlock_bh(&ip6_tnl_lock); 191 } 192 193 /** 194 * ip6_tnl_unlink - remove tunnel from hash table 195 * @t: tunnel to be removed 196 **/ 197 198 static void 199 ip6_tnl_unlink(struct ip6_tnl *t) 200 { 201 struct ip6_tnl **tp; 202 203 for (tp = ip6_tnl_bucket(&t->parms); *tp; tp = &(*tp)->next) { 204 if (t == *tp) { 205 write_lock_bh(&ip6_tnl_lock); 206 *tp = t->next; 207 write_unlock_bh(&ip6_tnl_lock); 208 break; 209 } 210 } 211 } 212 213 /** 214 * ip6_tnl_create() - create a new tunnel 215 * @p: tunnel parameters 216 * @pt: pointer to new tunnel 217 * 218 * Description: 219 * Create tunnel matching given parameters. 220 * 221 * Return: 222 * created tunnel or NULL 223 **/ 224 225 static struct ip6_tnl *ip6_tnl_create(struct ip6_tnl_parm *p) 226 { 227 struct net_device *dev; 228 struct ip6_tnl *t; 229 char name[IFNAMSIZ]; 230 int err; 231 232 if (p->name[0]) 233 strlcpy(name, p->name, IFNAMSIZ); 234 else 235 sprintf(name, "ip6tnl%%d"); 236 237 dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup); 238 if (dev == NULL) 239 goto failed; 240 241 if (strchr(name, '%')) { 242 if (dev_alloc_name(dev, name) < 0) 243 goto failed_free; 244 } 245 246 t = netdev_priv(dev); 247 dev->init = ip6_tnl_dev_init; 248 t->parms = *p; 249 250 if ((err = register_netdevice(dev)) < 0) 251 goto failed_free; 252 253 dev_hold(dev); 254 ip6_tnl_link(t); 255 return t; 256 257 failed_free: 258 free_netdev(dev); 259 failed: 260 return NULL; 261 } 262 263 /** 264 * ip6_tnl_locate - find or create tunnel matching given parameters 265 * @p: tunnel parameters 266 * @create: != 0 if allowed to create new tunnel if no match found 267 * 268 * Description: 269 * ip6_tnl_locate() first tries to locate an existing tunnel 270 * based on @parms. If this is unsuccessful, but @create is set a new 271 * tunnel device is created and registered for use. 272 * 273 * Return: 274 * matching tunnel or NULL 275 **/ 276 277 static struct ip6_tnl *ip6_tnl_locate(struct ip6_tnl_parm *p, int create) 278 { 279 struct in6_addr *remote = &p->raddr; 280 struct in6_addr *local = &p->laddr; 281 struct ip6_tnl *t; 282 283 for (t = *ip6_tnl_bucket(p); t; t = t->next) { 284 if (ipv6_addr_equal(local, &t->parms.laddr) && 285 ipv6_addr_equal(remote, &t->parms.raddr)) 286 return t; 287 } 288 if (!create) 289 return NULL; 290 return ip6_tnl_create(p); 291 } 292 293 /** 294 * ip6_tnl_dev_uninit - tunnel device uninitializer 295 * @dev: the device to be destroyed 296 * 297 * Description: 298 * ip6_tnl_dev_uninit() removes tunnel from its list 299 **/ 300 301 static void 302 ip6_tnl_dev_uninit(struct net_device *dev) 303 { 304 struct ip6_tnl *t = netdev_priv(dev); 305 306 if (dev == ip6_fb_tnl_dev) { 307 write_lock_bh(&ip6_tnl_lock); 308 tnls_wc[0] = NULL; 309 write_unlock_bh(&ip6_tnl_lock); 310 } else { 311 ip6_tnl_unlink(t); 312 } 313 ip6_tnl_dst_reset(t); 314 dev_put(dev); 315 } 316 317 /** 318 * parse_tvl_tnl_enc_lim - handle encapsulation limit option 319 * @skb: received socket buffer 320 * 321 * Return: 322 * 0 if none was found, 323 * else index to encapsulation limit 324 **/ 325 326 static __u16 327 parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw) 328 { 329 struct ipv6hdr *ipv6h = (struct ipv6hdr *) raw; 330 __u8 nexthdr = ipv6h->nexthdr; 331 __u16 off = sizeof (*ipv6h); 332 333 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 334 __u16 optlen = 0; 335 struct ipv6_opt_hdr *hdr; 336 if (raw + off + sizeof (*hdr) > skb->data && 337 !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr))) 338 break; 339 340 hdr = (struct ipv6_opt_hdr *) (raw + off); 341 if (nexthdr == NEXTHDR_FRAGMENT) { 342 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 343 if (frag_hdr->frag_off) 344 break; 345 optlen = 8; 346 } else if (nexthdr == NEXTHDR_AUTH) { 347 optlen = (hdr->hdrlen + 2) << 2; 348 } else { 349 optlen = ipv6_optlen(hdr); 350 } 351 if (nexthdr == NEXTHDR_DEST) { 352 __u16 i = off + 2; 353 while (1) { 354 struct ipv6_tlv_tnl_enc_lim *tel; 355 356 /* No more room for encapsulation limit */ 357 if (i + sizeof (*tel) > off + optlen) 358 break; 359 360 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i]; 361 /* return index of option if found and valid */ 362 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 363 tel->length == 1) 364 return i; 365 /* else jump to next option */ 366 if (tel->type) 367 i += tel->length + 2; 368 else 369 i++; 370 } 371 } 372 nexthdr = hdr->nexthdr; 373 off += optlen; 374 } 375 return 0; 376 } 377 378 /** 379 * ip6_tnl_err - tunnel error handler 380 * 381 * Description: 382 * ip6_tnl_err() should handle errors in the tunnel according 383 * to the specifications in RFC 2473. 384 **/ 385 386 static int 387 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 388 int *type, int *code, int *msg, __u32 *info, int offset) 389 { 390 struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data; 391 struct ip6_tnl *t; 392 int rel_msg = 0; 393 int rel_type = ICMPV6_DEST_UNREACH; 394 int rel_code = ICMPV6_ADDR_UNREACH; 395 __u32 rel_info = 0; 396 __u16 len; 397 int err = -ENOENT; 398 399 /* If the packet doesn't contain the original IPv6 header we are 400 in trouble since we might need the source address for further 401 processing of the error. */ 402 403 read_lock(&ip6_tnl_lock); 404 if ((t = ip6_tnl_lookup(&ipv6h->daddr, &ipv6h->saddr)) == NULL) 405 goto out; 406 407 if (t->parms.proto != ipproto && t->parms.proto != 0) 408 goto out; 409 410 err = 0; 411 412 switch (*type) { 413 __u32 teli; 414 struct ipv6_tlv_tnl_enc_lim *tel; 415 __u32 mtu; 416 case ICMPV6_DEST_UNREACH: 417 if (net_ratelimit()) 418 printk(KERN_WARNING 419 "%s: Path to destination invalid " 420 "or inactive!\n", t->parms.name); 421 rel_msg = 1; 422 break; 423 case ICMPV6_TIME_EXCEED: 424 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 425 if (net_ratelimit()) 426 printk(KERN_WARNING 427 "%s: Too small hop limit or " 428 "routing loop in tunnel!\n", 429 t->parms.name); 430 rel_msg = 1; 431 } 432 break; 433 case ICMPV6_PARAMPROB: 434 teli = 0; 435 if ((*code) == ICMPV6_HDR_FIELD) 436 teli = parse_tlv_tnl_enc_lim(skb, skb->data); 437 438 if (teli && teli == *info - 2) { 439 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 440 if (tel->encap_limit == 0) { 441 if (net_ratelimit()) 442 printk(KERN_WARNING 443 "%s: Too small encapsulation " 444 "limit or routing loop in " 445 "tunnel!\n", t->parms.name); 446 rel_msg = 1; 447 } 448 } else if (net_ratelimit()) { 449 printk(KERN_WARNING 450 "%s: Recipient unable to parse tunneled " 451 "packet!\n ", t->parms.name); 452 } 453 break; 454 case ICMPV6_PKT_TOOBIG: 455 mtu = *info - offset; 456 if (mtu < IPV6_MIN_MTU) 457 mtu = IPV6_MIN_MTU; 458 t->dev->mtu = mtu; 459 460 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) { 461 rel_type = ICMPV6_PKT_TOOBIG; 462 rel_code = 0; 463 rel_info = mtu; 464 rel_msg = 1; 465 } 466 break; 467 } 468 469 *type = rel_type; 470 *code = rel_code; 471 *info = rel_info; 472 *msg = rel_msg; 473 474 out: 475 read_unlock(&ip6_tnl_lock); 476 return err; 477 } 478 479 static int 480 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 481 int type, int code, int offset, __be32 info) 482 { 483 int rel_msg = 0; 484 int rel_type = type; 485 int rel_code = code; 486 __u32 rel_info = ntohl(info); 487 int err; 488 struct sk_buff *skb2; 489 struct iphdr *eiph; 490 struct flowi fl; 491 struct rtable *rt; 492 493 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 494 &rel_msg, &rel_info, offset); 495 if (err < 0) 496 return err; 497 498 if (rel_msg == 0) 499 return 0; 500 501 switch (rel_type) { 502 case ICMPV6_DEST_UNREACH: 503 if (rel_code != ICMPV6_ADDR_UNREACH) 504 return 0; 505 rel_type = ICMP_DEST_UNREACH; 506 rel_code = ICMP_HOST_UNREACH; 507 break; 508 case ICMPV6_PKT_TOOBIG: 509 if (rel_code != 0) 510 return 0; 511 rel_type = ICMP_DEST_UNREACH; 512 rel_code = ICMP_FRAG_NEEDED; 513 break; 514 default: 515 return 0; 516 } 517 518 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 519 return 0; 520 521 skb2 = skb_clone(skb, GFP_ATOMIC); 522 if (!skb2) 523 return 0; 524 525 dst_release(skb2->dst); 526 skb2->dst = NULL; 527 skb_pull(skb2, offset); 528 skb_reset_network_header(skb2); 529 eiph = ip_hdr(skb2); 530 531 /* Try to guess incoming interface */ 532 memset(&fl, 0, sizeof(fl)); 533 fl.fl4_dst = eiph->saddr; 534 fl.fl4_tos = RT_TOS(eiph->tos); 535 fl.proto = IPPROTO_IPIP; 536 if (ip_route_output_key(&init_net, &rt, &fl)) 537 goto out; 538 539 skb2->dev = rt->u.dst.dev; 540 541 /* route "incoming" packet */ 542 if (rt->rt_flags & RTCF_LOCAL) { 543 ip_rt_put(rt); 544 rt = NULL; 545 fl.fl4_dst = eiph->daddr; 546 fl.fl4_src = eiph->saddr; 547 fl.fl4_tos = eiph->tos; 548 if (ip_route_output_key(&init_net, &rt, &fl) || 549 rt->u.dst.dev->type != ARPHRD_TUNNEL) { 550 ip_rt_put(rt); 551 goto out; 552 } 553 skb2->dst = (struct dst_entry *)rt; 554 } else { 555 ip_rt_put(rt); 556 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 557 skb2->dev) || 558 skb2->dst->dev->type != ARPHRD_TUNNEL) 559 goto out; 560 } 561 562 /* change mtu on this route */ 563 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 564 if (rel_info > dst_mtu(skb2->dst)) 565 goto out; 566 567 skb2->dst->ops->update_pmtu(skb2->dst, rel_info); 568 } 569 570 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 571 572 out: 573 kfree_skb(skb2); 574 return 0; 575 } 576 577 static int 578 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 579 int type, int code, int offset, __be32 info) 580 { 581 int rel_msg = 0; 582 int rel_type = type; 583 int rel_code = code; 584 __u32 rel_info = ntohl(info); 585 int err; 586 587 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 588 &rel_msg, &rel_info, offset); 589 if (err < 0) 590 return err; 591 592 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 593 struct rt6_info *rt; 594 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 595 596 if (!skb2) 597 return 0; 598 599 dst_release(skb2->dst); 600 skb2->dst = NULL; 601 skb_pull(skb2, offset); 602 skb_reset_network_header(skb2); 603 604 /* Try to guess incoming interface */ 605 rt = rt6_lookup(&ipv6_hdr(skb2)->saddr, NULL, 0, 0); 606 607 if (rt && rt->rt6i_dev) 608 skb2->dev = rt->rt6i_dev; 609 610 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev); 611 612 if (rt) 613 dst_release(&rt->u.dst); 614 615 kfree_skb(skb2); 616 } 617 618 return 0; 619 } 620 621 static void ip4ip6_dscp_ecn_decapsulate(struct ip6_tnl *t, 622 struct ipv6hdr *ipv6h, 623 struct sk_buff *skb) 624 { 625 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 626 627 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 628 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 629 630 if (INET_ECN_is_ce(dsfield)) 631 IP_ECN_set_ce(ip_hdr(skb)); 632 } 633 634 static void ip6ip6_dscp_ecn_decapsulate(struct ip6_tnl *t, 635 struct ipv6hdr *ipv6h, 636 struct sk_buff *skb) 637 { 638 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 639 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 640 641 if (INET_ECN_is_ce(ipv6_get_dsfield(ipv6h))) 642 IP6_ECN_set_ce(ipv6_hdr(skb)); 643 } 644 645 static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t) 646 { 647 struct ip6_tnl_parm *p = &t->parms; 648 int ret = 0; 649 650 if (p->flags & IP6_TNL_F_CAP_RCV) { 651 struct net_device *ldev = NULL; 652 653 if (p->link) 654 ldev = dev_get_by_index(&init_net, p->link); 655 656 if ((ipv6_addr_is_multicast(&p->laddr) || 657 likely(ipv6_chk_addr(&init_net, &p->laddr, ldev, 0))) && 658 likely(!ipv6_chk_addr(&init_net, &p->raddr, NULL, 0))) 659 ret = 1; 660 661 if (ldev) 662 dev_put(ldev); 663 } 664 return ret; 665 } 666 667 /** 668 * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally 669 * @skb: received socket buffer 670 * @protocol: ethernet protocol ID 671 * @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN 672 * 673 * Return: 0 674 **/ 675 676 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, 677 __u8 ipproto, 678 void (*dscp_ecn_decapsulate)(struct ip6_tnl *t, 679 struct ipv6hdr *ipv6h, 680 struct sk_buff *skb)) 681 { 682 struct ip6_tnl *t; 683 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 684 685 read_lock(&ip6_tnl_lock); 686 687 if ((t = ip6_tnl_lookup(&ipv6h->saddr, &ipv6h->daddr)) != NULL) { 688 if (t->parms.proto != ipproto && t->parms.proto != 0) { 689 read_unlock(&ip6_tnl_lock); 690 goto discard; 691 } 692 693 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 694 read_unlock(&ip6_tnl_lock); 695 goto discard; 696 } 697 698 if (!ip6_tnl_rcv_ctl(t)) { 699 t->stat.rx_dropped++; 700 read_unlock(&ip6_tnl_lock); 701 goto discard; 702 } 703 secpath_reset(skb); 704 skb->mac_header = skb->network_header; 705 skb_reset_network_header(skb); 706 skb->protocol = htons(protocol); 707 skb->pkt_type = PACKET_HOST; 708 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 709 skb->dev = t->dev; 710 dst_release(skb->dst); 711 skb->dst = NULL; 712 nf_reset(skb); 713 714 dscp_ecn_decapsulate(t, ipv6h, skb); 715 716 t->stat.rx_packets++; 717 t->stat.rx_bytes += skb->len; 718 netif_rx(skb); 719 read_unlock(&ip6_tnl_lock); 720 return 0; 721 } 722 read_unlock(&ip6_tnl_lock); 723 return 1; 724 725 discard: 726 kfree_skb(skb); 727 return 0; 728 } 729 730 static int ip4ip6_rcv(struct sk_buff *skb) 731 { 732 return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP, 733 ip4ip6_dscp_ecn_decapsulate); 734 } 735 736 static int ip6ip6_rcv(struct sk_buff *skb) 737 { 738 return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6, 739 ip6ip6_dscp_ecn_decapsulate); 740 } 741 742 struct ipv6_tel_txoption { 743 struct ipv6_txoptions ops; 744 __u8 dst_opt[8]; 745 }; 746 747 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 748 { 749 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 750 751 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 752 opt->dst_opt[3] = 1; 753 opt->dst_opt[4] = encap_limit; 754 opt->dst_opt[5] = IPV6_TLV_PADN; 755 opt->dst_opt[6] = 1; 756 757 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 758 opt->ops.opt_nflen = 8; 759 } 760 761 /** 762 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 763 * @t: the outgoing tunnel device 764 * @hdr: IPv6 header from the incoming packet 765 * 766 * Description: 767 * Avoid trivial tunneling loop by checking that tunnel exit-point 768 * doesn't match source of incoming packet. 769 * 770 * Return: 771 * 1 if conflict, 772 * 0 else 773 **/ 774 775 static inline int 776 ip6_tnl_addr_conflict(struct ip6_tnl *t, struct ipv6hdr *hdr) 777 { 778 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 779 } 780 781 static inline int ip6_tnl_xmit_ctl(struct ip6_tnl *t) 782 { 783 struct ip6_tnl_parm *p = &t->parms; 784 int ret = 0; 785 786 if (p->flags & IP6_TNL_F_CAP_XMIT) { 787 struct net_device *ldev = NULL; 788 789 if (p->link) 790 ldev = dev_get_by_index(&init_net, p->link); 791 792 if (unlikely(!ipv6_chk_addr(&init_net, &p->laddr, ldev, 0))) 793 printk(KERN_WARNING 794 "%s xmit: Local address not yet configured!\n", 795 p->name); 796 else if (!ipv6_addr_is_multicast(&p->raddr) && 797 unlikely(ipv6_chk_addr(&init_net, &p->raddr, NULL, 0))) 798 printk(KERN_WARNING 799 "%s xmit: Routing loop! " 800 "Remote address found on this node!\n", 801 p->name); 802 else 803 ret = 1; 804 if (ldev) 805 dev_put(ldev); 806 } 807 return ret; 808 } 809 /** 810 * ip6_tnl_xmit2 - encapsulate packet and send 811 * @skb: the outgoing socket buffer 812 * @dev: the outgoing tunnel device 813 * @dsfield: dscp code for outer header 814 * @fl: flow of tunneled packet 815 * @encap_limit: encapsulation limit 816 * @pmtu: Path MTU is stored if packet is too big 817 * 818 * Description: 819 * Build new header and do some sanity checks on the packet before sending 820 * it. 821 * 822 * Return: 823 * 0 on success 824 * -1 fail 825 * %-EMSGSIZE message too big. return mtu in this case. 826 **/ 827 828 static int ip6_tnl_xmit2(struct sk_buff *skb, 829 struct net_device *dev, 830 __u8 dsfield, 831 struct flowi *fl, 832 int encap_limit, 833 __u32 *pmtu) 834 { 835 struct ip6_tnl *t = netdev_priv(dev); 836 struct net_device_stats *stats = &t->stat; 837 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 838 struct ipv6_tel_txoption opt; 839 struct dst_entry *dst; 840 struct net_device *tdev; 841 int mtu; 842 unsigned int max_headroom = sizeof(struct ipv6hdr); 843 u8 proto; 844 int err = -1; 845 int pkt_len; 846 847 if ((dst = ip6_tnl_dst_check(t)) != NULL) 848 dst_hold(dst); 849 else { 850 dst = ip6_route_output(NULL, fl); 851 852 if (dst->error || xfrm_lookup(&dst, fl, NULL, 0) < 0) 853 goto tx_err_link_failure; 854 } 855 856 tdev = dst->dev; 857 858 if (tdev == dev) { 859 stats->collisions++; 860 if (net_ratelimit()) 861 printk(KERN_WARNING 862 "%s: Local routing loop detected!\n", 863 t->parms.name); 864 goto tx_err_dst_release; 865 } 866 mtu = dst_mtu(dst) - sizeof (*ipv6h); 867 if (encap_limit >= 0) { 868 max_headroom += 8; 869 mtu -= 8; 870 } 871 if (mtu < IPV6_MIN_MTU) 872 mtu = IPV6_MIN_MTU; 873 if (skb->dst) 874 skb->dst->ops->update_pmtu(skb->dst, mtu); 875 if (skb->len > mtu) { 876 *pmtu = mtu; 877 err = -EMSGSIZE; 878 goto tx_err_dst_release; 879 } 880 881 /* 882 * Okay, now see if we can stuff it in the buffer as-is. 883 */ 884 max_headroom += LL_RESERVED_SPACE(tdev); 885 886 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 887 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 888 struct sk_buff *new_skb; 889 890 if (!(new_skb = skb_realloc_headroom(skb, max_headroom))) 891 goto tx_err_dst_release; 892 893 if (skb->sk) 894 skb_set_owner_w(new_skb, skb->sk); 895 kfree_skb(skb); 896 skb = new_skb; 897 } 898 dst_release(skb->dst); 899 skb->dst = dst_clone(dst); 900 901 skb->transport_header = skb->network_header; 902 903 proto = fl->proto; 904 if (encap_limit >= 0) { 905 init_tel_txopt(&opt, encap_limit); 906 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 907 } 908 skb_push(skb, sizeof(struct ipv6hdr)); 909 skb_reset_network_header(skb); 910 ipv6h = ipv6_hdr(skb); 911 *(__be32*)ipv6h = fl->fl6_flowlabel | htonl(0x60000000); 912 dsfield = INET_ECN_encapsulate(0, dsfield); 913 ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield); 914 ipv6h->hop_limit = t->parms.hop_limit; 915 ipv6h->nexthdr = proto; 916 ipv6_addr_copy(&ipv6h->saddr, &fl->fl6_src); 917 ipv6_addr_copy(&ipv6h->daddr, &fl->fl6_dst); 918 nf_reset(skb); 919 pkt_len = skb->len; 920 err = ip6_local_out(skb); 921 922 if (net_xmit_eval(err) == 0) { 923 stats->tx_bytes += pkt_len; 924 stats->tx_packets++; 925 } else { 926 stats->tx_errors++; 927 stats->tx_aborted_errors++; 928 } 929 ip6_tnl_dst_store(t, dst); 930 return 0; 931 tx_err_link_failure: 932 stats->tx_carrier_errors++; 933 dst_link_failure(skb); 934 tx_err_dst_release: 935 dst_release(dst); 936 return err; 937 } 938 939 static inline int 940 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 941 { 942 struct ip6_tnl *t = netdev_priv(dev); 943 struct iphdr *iph = ip_hdr(skb); 944 int encap_limit = -1; 945 struct flowi fl; 946 __u8 dsfield; 947 __u32 mtu; 948 int err; 949 950 if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) || 951 !ip6_tnl_xmit_ctl(t)) 952 return -1; 953 954 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 955 encap_limit = t->parms.encap_limit; 956 957 memcpy(&fl, &t->fl, sizeof (fl)); 958 fl.proto = IPPROTO_IPIP; 959 960 dsfield = ipv4_get_dsfield(iph); 961 962 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 963 fl.fl6_flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 964 & IPV6_TCLASS_MASK; 965 966 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu); 967 if (err != 0) { 968 /* XXX: send ICMP error even if DF is not set. */ 969 if (err == -EMSGSIZE) 970 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 971 htonl(mtu)); 972 return -1; 973 } 974 975 return 0; 976 } 977 978 static inline int 979 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 980 { 981 struct ip6_tnl *t = netdev_priv(dev); 982 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 983 int encap_limit = -1; 984 __u16 offset; 985 struct flowi fl; 986 __u8 dsfield; 987 __u32 mtu; 988 int err; 989 990 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 991 !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h)) 992 return -1; 993 994 offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb)); 995 if (offset > 0) { 996 struct ipv6_tlv_tnl_enc_lim *tel; 997 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 998 if (tel->encap_limit == 0) { 999 icmpv6_send(skb, ICMPV6_PARAMPROB, 1000 ICMPV6_HDR_FIELD, offset + 2, skb->dev); 1001 return -1; 1002 } 1003 encap_limit = tel->encap_limit - 1; 1004 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1005 encap_limit = t->parms.encap_limit; 1006 1007 memcpy(&fl, &t->fl, sizeof (fl)); 1008 fl.proto = IPPROTO_IPV6; 1009 1010 dsfield = ipv6_get_dsfield(ipv6h); 1011 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 1012 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 1013 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1014 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 1015 1016 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu); 1017 if (err != 0) { 1018 if (err == -EMSGSIZE) 1019 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev); 1020 return -1; 1021 } 1022 1023 return 0; 1024 } 1025 1026 static int 1027 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1028 { 1029 struct ip6_tnl *t = netdev_priv(dev); 1030 struct net_device_stats *stats = &t->stat; 1031 int ret; 1032 1033 if (t->recursion++) { 1034 t->stat.collisions++; 1035 goto tx_err; 1036 } 1037 1038 switch (skb->protocol) { 1039 case __constant_htons(ETH_P_IP): 1040 ret = ip4ip6_tnl_xmit(skb, dev); 1041 break; 1042 case __constant_htons(ETH_P_IPV6): 1043 ret = ip6ip6_tnl_xmit(skb, dev); 1044 break; 1045 default: 1046 goto tx_err; 1047 } 1048 1049 if (ret < 0) 1050 goto tx_err; 1051 1052 t->recursion--; 1053 return 0; 1054 1055 tx_err: 1056 stats->tx_errors++; 1057 stats->tx_dropped++; 1058 kfree_skb(skb); 1059 t->recursion--; 1060 return 0; 1061 } 1062 1063 static void ip6_tnl_set_cap(struct ip6_tnl *t) 1064 { 1065 struct ip6_tnl_parm *p = &t->parms; 1066 int ltype = ipv6_addr_type(&p->laddr); 1067 int rtype = ipv6_addr_type(&p->raddr); 1068 1069 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV); 1070 1071 if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1072 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1073 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 1074 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 1075 if (ltype&IPV6_ADDR_UNICAST) 1076 p->flags |= IP6_TNL_F_CAP_XMIT; 1077 if (rtype&IPV6_ADDR_UNICAST) 1078 p->flags |= IP6_TNL_F_CAP_RCV; 1079 } 1080 } 1081 1082 static void ip6_tnl_link_config(struct ip6_tnl *t) 1083 { 1084 struct net_device *dev = t->dev; 1085 struct ip6_tnl_parm *p = &t->parms; 1086 struct flowi *fl = &t->fl; 1087 1088 memcpy(&dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1089 memcpy(&dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1090 1091 /* Set up flowi template */ 1092 ipv6_addr_copy(&fl->fl6_src, &p->laddr); 1093 ipv6_addr_copy(&fl->fl6_dst, &p->raddr); 1094 fl->oif = p->link; 1095 fl->fl6_flowlabel = 0; 1096 1097 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1098 fl->fl6_flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1099 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1100 fl->fl6_flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1101 1102 ip6_tnl_set_cap(t); 1103 1104 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1105 dev->flags |= IFF_POINTOPOINT; 1106 else 1107 dev->flags &= ~IFF_POINTOPOINT; 1108 1109 dev->iflink = p->link; 1110 1111 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1112 int strict = (ipv6_addr_type(&p->raddr) & 1113 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1114 1115 struct rt6_info *rt = rt6_lookup(&p->raddr, &p->laddr, 1116 p->link, strict); 1117 1118 if (rt == NULL) 1119 return; 1120 1121 if (rt->rt6i_dev) { 1122 dev->hard_header_len = rt->rt6i_dev->hard_header_len + 1123 sizeof (struct ipv6hdr); 1124 1125 dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr); 1126 1127 if (dev->mtu < IPV6_MIN_MTU) 1128 dev->mtu = IPV6_MIN_MTU; 1129 } 1130 dst_release(&rt->u.dst); 1131 } 1132 } 1133 1134 /** 1135 * ip6_tnl_change - update the tunnel parameters 1136 * @t: tunnel to be changed 1137 * @p: tunnel configuration parameters 1138 * @active: != 0 if tunnel is ready for use 1139 * 1140 * Description: 1141 * ip6_tnl_change() updates the tunnel parameters 1142 **/ 1143 1144 static int 1145 ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p) 1146 { 1147 ipv6_addr_copy(&t->parms.laddr, &p->laddr); 1148 ipv6_addr_copy(&t->parms.raddr, &p->raddr); 1149 t->parms.flags = p->flags; 1150 t->parms.hop_limit = p->hop_limit; 1151 t->parms.encap_limit = p->encap_limit; 1152 t->parms.flowinfo = p->flowinfo; 1153 t->parms.link = p->link; 1154 t->parms.proto = p->proto; 1155 ip6_tnl_dst_reset(t); 1156 ip6_tnl_link_config(t); 1157 return 0; 1158 } 1159 1160 /** 1161 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1162 * @dev: virtual device associated with tunnel 1163 * @ifr: parameters passed from userspace 1164 * @cmd: command to be performed 1165 * 1166 * Description: 1167 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1168 * from userspace. 1169 * 1170 * The possible commands are the following: 1171 * %SIOCGETTUNNEL: get tunnel parameters for device 1172 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1173 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1174 * %SIOCDELTUNNEL: delete tunnel 1175 * 1176 * The fallback device "ip6tnl0", created during module 1177 * initialization, can be used for creating other tunnel devices. 1178 * 1179 * Return: 1180 * 0 on success, 1181 * %-EFAULT if unable to copy data to or from userspace, 1182 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1183 * %-EINVAL if passed tunnel parameters are invalid, 1184 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1185 * %-ENODEV if attempting to change or delete a nonexisting device 1186 **/ 1187 1188 static int 1189 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1190 { 1191 int err = 0; 1192 struct ip6_tnl_parm p; 1193 struct ip6_tnl *t = NULL; 1194 1195 switch (cmd) { 1196 case SIOCGETTUNNEL: 1197 if (dev == ip6_fb_tnl_dev) { 1198 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) { 1199 err = -EFAULT; 1200 break; 1201 } 1202 t = ip6_tnl_locate(&p, 0); 1203 } 1204 if (t == NULL) 1205 t = netdev_priv(dev); 1206 memcpy(&p, &t->parms, sizeof (p)); 1207 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) { 1208 err = -EFAULT; 1209 } 1210 break; 1211 case SIOCADDTUNNEL: 1212 case SIOCCHGTUNNEL: 1213 err = -EPERM; 1214 if (!capable(CAP_NET_ADMIN)) 1215 break; 1216 err = -EFAULT; 1217 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1218 break; 1219 err = -EINVAL; 1220 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1221 p.proto != 0) 1222 break; 1223 t = ip6_tnl_locate(&p, cmd == SIOCADDTUNNEL); 1224 if (dev != ip6_fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 1225 if (t != NULL) { 1226 if (t->dev != dev) { 1227 err = -EEXIST; 1228 break; 1229 } 1230 } else 1231 t = netdev_priv(dev); 1232 1233 ip6_tnl_unlink(t); 1234 err = ip6_tnl_change(t, &p); 1235 ip6_tnl_link(t); 1236 netdev_state_change(dev); 1237 } 1238 if (t) { 1239 err = 0; 1240 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p))) 1241 err = -EFAULT; 1242 1243 } else 1244 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1245 break; 1246 case SIOCDELTUNNEL: 1247 err = -EPERM; 1248 if (!capable(CAP_NET_ADMIN)) 1249 break; 1250 1251 if (dev == ip6_fb_tnl_dev) { 1252 err = -EFAULT; 1253 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1254 break; 1255 err = -ENOENT; 1256 if ((t = ip6_tnl_locate(&p, 0)) == NULL) 1257 break; 1258 err = -EPERM; 1259 if (t->dev == ip6_fb_tnl_dev) 1260 break; 1261 dev = t->dev; 1262 } 1263 err = 0; 1264 unregister_netdevice(dev); 1265 break; 1266 default: 1267 err = -EINVAL; 1268 } 1269 return err; 1270 } 1271 1272 /** 1273 * ip6_tnl_get_stats - return the stats for tunnel device 1274 * @dev: virtual device associated with tunnel 1275 * 1276 * Return: stats for device 1277 **/ 1278 1279 static struct net_device_stats * 1280 ip6_tnl_get_stats(struct net_device *dev) 1281 { 1282 return &(((struct ip6_tnl *)netdev_priv(dev))->stat); 1283 } 1284 1285 /** 1286 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1287 * @dev: virtual device associated with tunnel 1288 * @new_mtu: the new mtu 1289 * 1290 * Return: 1291 * 0 on success, 1292 * %-EINVAL if mtu too small 1293 **/ 1294 1295 static int 1296 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1297 { 1298 if (new_mtu < IPV6_MIN_MTU) { 1299 return -EINVAL; 1300 } 1301 dev->mtu = new_mtu; 1302 return 0; 1303 } 1304 1305 /** 1306 * ip6_tnl_dev_setup - setup virtual tunnel device 1307 * @dev: virtual device associated with tunnel 1308 * 1309 * Description: 1310 * Initialize function pointers and device parameters 1311 **/ 1312 1313 static void ip6_tnl_dev_setup(struct net_device *dev) 1314 { 1315 dev->uninit = ip6_tnl_dev_uninit; 1316 dev->destructor = free_netdev; 1317 dev->hard_start_xmit = ip6_tnl_xmit; 1318 dev->get_stats = ip6_tnl_get_stats; 1319 dev->do_ioctl = ip6_tnl_ioctl; 1320 dev->change_mtu = ip6_tnl_change_mtu; 1321 1322 dev->type = ARPHRD_TUNNEL6; 1323 dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr); 1324 dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr); 1325 dev->flags |= IFF_NOARP; 1326 dev->addr_len = sizeof(struct in6_addr); 1327 } 1328 1329 1330 /** 1331 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1332 * @dev: virtual device associated with tunnel 1333 **/ 1334 1335 static inline void 1336 ip6_tnl_dev_init_gen(struct net_device *dev) 1337 { 1338 struct ip6_tnl *t = netdev_priv(dev); 1339 t->dev = dev; 1340 strcpy(t->parms.name, dev->name); 1341 } 1342 1343 /** 1344 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1345 * @dev: virtual device associated with tunnel 1346 **/ 1347 1348 static int 1349 ip6_tnl_dev_init(struct net_device *dev) 1350 { 1351 struct ip6_tnl *t = netdev_priv(dev); 1352 ip6_tnl_dev_init_gen(dev); 1353 ip6_tnl_link_config(t); 1354 return 0; 1355 } 1356 1357 /** 1358 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1359 * @dev: fallback device 1360 * 1361 * Return: 0 1362 **/ 1363 1364 static int 1365 ip6_fb_tnl_dev_init(struct net_device *dev) 1366 { 1367 struct ip6_tnl *t = netdev_priv(dev); 1368 ip6_tnl_dev_init_gen(dev); 1369 t->parms.proto = IPPROTO_IPV6; 1370 dev_hold(dev); 1371 tnls_wc[0] = t; 1372 return 0; 1373 } 1374 1375 static struct xfrm6_tunnel ip4ip6_handler = { 1376 .handler = ip4ip6_rcv, 1377 .err_handler = ip4ip6_err, 1378 .priority = 1, 1379 }; 1380 1381 static struct xfrm6_tunnel ip6ip6_handler = { 1382 .handler = ip6ip6_rcv, 1383 .err_handler = ip6ip6_err, 1384 .priority = 1, 1385 }; 1386 1387 /** 1388 * ip6_tunnel_init - register protocol and reserve needed resources 1389 * 1390 * Return: 0 on success 1391 **/ 1392 1393 static int __init ip6_tunnel_init(void) 1394 { 1395 int err; 1396 1397 if (xfrm6_tunnel_register(&ip4ip6_handler, AF_INET)) { 1398 printk(KERN_ERR "ip6_tunnel init: can't register ip4ip6\n"); 1399 err = -EAGAIN; 1400 goto out; 1401 } 1402 1403 if (xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6)) { 1404 printk(KERN_ERR "ip6_tunnel init: can't register ip6ip6\n"); 1405 err = -EAGAIN; 1406 goto unreg_ip4ip6; 1407 } 1408 ip6_fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 1409 ip6_tnl_dev_setup); 1410 1411 if (!ip6_fb_tnl_dev) { 1412 err = -ENOMEM; 1413 goto fail; 1414 } 1415 ip6_fb_tnl_dev->init = ip6_fb_tnl_dev_init; 1416 1417 if ((err = register_netdev(ip6_fb_tnl_dev))) { 1418 free_netdev(ip6_fb_tnl_dev); 1419 goto fail; 1420 } 1421 return 0; 1422 fail: 1423 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 1424 unreg_ip4ip6: 1425 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 1426 out: 1427 return err; 1428 } 1429 1430 static void __exit ip6_tnl_destroy_tunnels(void) 1431 { 1432 int h; 1433 struct ip6_tnl *t; 1434 1435 for (h = 0; h < HASH_SIZE; h++) { 1436 while ((t = tnls_r_l[h]) != NULL) 1437 unregister_netdevice(t->dev); 1438 } 1439 1440 t = tnls_wc[0]; 1441 unregister_netdevice(t->dev); 1442 } 1443 1444 /** 1445 * ip6_tunnel_cleanup - free resources and unregister protocol 1446 **/ 1447 1448 static void __exit ip6_tunnel_cleanup(void) 1449 { 1450 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 1451 printk(KERN_INFO "ip6_tunnel close: can't deregister ip4ip6\n"); 1452 1453 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 1454 printk(KERN_INFO "ip6_tunnel close: can't deregister ip6ip6\n"); 1455 1456 rtnl_lock(); 1457 ip6_tnl_destroy_tunnels(); 1458 rtnl_unlock(); 1459 } 1460 1461 module_init(ip6_tunnel_init); 1462 module_exit(ip6_tunnel_cleanup); 1463