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: ip6_tunnel.c,v 1.1.1.1 2007/08/03 18:53:52 Exp $ 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 56MODULE_AUTHOR("Ville Nuorvala"); 57MODULE_DESCRIPTION("IPv6 tunneling device"); 58MODULE_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 77static int ip6_fb_tnl_dev_init(struct net_device *dev); 78static int ip6_tnl_dev_init(struct net_device *dev); 79static void ip6_tnl_dev_setup(struct net_device *dev); 80 81/* the IPv6 tunnel fallback device */ 82static struct net_device *ip6_fb_tnl_dev; 83 84 85/* lists for storing tunnels in use */ 86static struct ip6_tnl *tnls_r_l[HASH_SIZE]; 87static struct ip6_tnl *tnls_wc[1]; 88static struct ip6_tnl **tnls[2] = { tnls_wc, tnls_r_l }; 89 90/* lock for the tunnel lists */ 91static DEFINE_RWLOCK(ip6_tnl_lock); 92 93static 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 107static inline void ip6_tnl_dst_reset(struct ip6_tnl *t) 108{ 109 dst_release(t->dst_cache); 110 t->dst_cache = NULL; 111} 112 113static 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 132static struct ip6_tnl * 133ip6_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 162static struct ip6_tnl ** 163ip6_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 182static void 183ip6_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 198static void 199ip6_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 225static 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 int i; 236 for (i = 1; i < IP6_TNL_MAX; i++) { 237 sprintf(name, "ip6tnl%d", i); 238 if (__dev_get_by_name(name) == NULL) 239 break; 240 } 241 if (i == IP6_TNL_MAX) 242 goto failed; 243 } 244 dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup); 245 if (dev == NULL) 246 goto failed; 247 248 t = netdev_priv(dev); 249 dev->init = ip6_tnl_dev_init; 250 t->parms = *p; 251 252 if ((err = register_netdevice(dev)) < 0) { 253 free_netdev(dev); 254 goto failed; 255 } 256 dev_hold(dev); 257 ip6_tnl_link(t); 258 return t; 259failed: 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 277static 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 301static void 302ip6_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 326static __u16 327parse_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 386static int 387ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 388 int *type, int *code, int *msg, __be32 *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 == ntohl(*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 = ntohl(*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 474out: 475 read_unlock(&ip6_tnl_lock); 476 return err; 477} 478 479static int 480ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 481 int type, int code, int offset, __u32 info) 482{ 483 int rel_msg = 0; 484 int rel_type = type; 485 int rel_code = code; 486 __u32 rel_info = 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(&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(&rt, &fl) || 549 rt->u.dst.dev->type != ARPHRD_TUNNEL) { 550 ip_rt_put(rt); 551 goto out; 552 } 553 } else { 554 ip_rt_put(rt); 555 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 556 skb2->dev) || 557 skb2->dst->dev->type != ARPHRD_TUNNEL) 558 goto out; 559 } 560 561 /* change mtu on this route */ 562 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 563 if (rel_info > dst_mtu(skb2->dst)) 564 goto out; 565 566 skb2->dst->ops->update_pmtu(skb2->dst, rel_info); 567 rel_info = htonl(rel_info); 568 } 569 570 icmp_send(skb2, rel_type, rel_code, rel_info); 571 572out: 573 kfree_skb(skb2); 574 return 0; 575} 576 577static int 578ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 579 int type, int code, int offset, __u32 info) 580{ 581 int rel_msg = 0; 582 int rel_type = type; 583 int rel_code = code; 584 __u32 rel_info = 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 621static 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 634static 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(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 645static 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(p->link); 655 656 if ((ipv6_addr_is_multicast(&p->laddr) || 657 likely(ipv6_chk_addr(&p->laddr, ldev, 0))) && 658 likely(!ipv6_chk_addr(&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 676static 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 725discard: 726 kfree_skb(skb); 727 return 0; 728} 729 730static 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 736static 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 742struct ipv6_tel_txoption { 743 struct ipv6_txoptions ops; 744 __u8 dst_opt[8]; 745}; 746 747static 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 775static inline int 776ip6_tnl_addr_conflict(struct ip6_tnl *t, struct ipv6hdr *hdr) 777{ 778 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 779} 780 781static 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(p->link); 791 792 if (unlikely(!ipv6_chk_addr(&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(&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 828static 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 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 || 887 skb_cloned(skb) || skb_shared(skb)) { 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->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 915 ipv6h->hop_limit = t->parms.hop_limit; 916 ipv6h->nexthdr = proto; 917 ipv6_addr_copy(&ipv6h->saddr, &fl->fl6_src); 918 ipv6_addr_copy(&ipv6h->daddr, &fl->fl6_dst); 919 nf_reset(skb); 920 pkt_len = skb->len; 921 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, 922 skb->dst->dev, dst_output); 923 924 if (net_xmit_eval(err) == 0) { 925 stats->tx_bytes += pkt_len; 926 stats->tx_packets++; 927 } else { 928 stats->tx_errors++; 929 stats->tx_aborted_errors++; 930 } 931 ip6_tnl_dst_store(t, dst); 932 return 0; 933tx_err_link_failure: 934 stats->tx_carrier_errors++; 935 dst_link_failure(skb); 936tx_err_dst_release: 937 dst_release(dst); 938 return err; 939} 940 941static inline int 942ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 943{ 944 struct ip6_tnl *t = netdev_priv(dev); 945 struct iphdr *iph = ip_hdr(skb); 946 int encap_limit = -1; 947 struct flowi fl; 948 __u8 dsfield; 949 __u32 mtu; 950 int err; 951 952 if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) || 953 !ip6_tnl_xmit_ctl(t)) 954 return -1; 955 956 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 957 encap_limit = t->parms.encap_limit; 958 959 memcpy(&fl, &t->fl, sizeof (fl)); 960 fl.proto = IPPROTO_IPIP; 961 962 dsfield = ipv4_get_dsfield(iph); 963 964 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 965 fl.fl6_flowlabel |= ntohl(((__u32)iph->tos << IPV6_TCLASS_SHIFT) 966 & IPV6_TCLASS_MASK); 967 968 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu); 969 if (err != 0) { 970 if (err == -EMSGSIZE) 971 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 972 htonl(mtu)); 973 return -1; 974 } 975 976 return 0; 977} 978 979static inline int 980ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 981{ 982 struct ip6_tnl *t = netdev_priv(dev); 983 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 984 int encap_limit = -1; 985 __u16 offset; 986 struct flowi fl; 987 __u8 dsfield; 988 __u32 mtu; 989 int err; 990 991 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 992 !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h)) 993 return -1; 994 995 offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb)); 996 if (offset > 0) { 997 struct ipv6_tlv_tnl_enc_lim *tel; 998 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 999 if (tel->encap_limit == 0) { 1000 icmpv6_send(skb, ICMPV6_PARAMPROB, 1001 ICMPV6_HDR_FIELD, offset + 2, skb->dev); 1002 return -1; 1003 } 1004 encap_limit = tel->encap_limit - 1; 1005 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1006 encap_limit = t->parms.encap_limit; 1007 1008 memcpy(&fl, &t->fl, sizeof (fl)); 1009 fl.proto = IPPROTO_IPV6; 1010 1011 dsfield = ipv6_get_dsfield(ipv6h); 1012 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 1013 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 1014 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1015 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 1016 1017 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu); 1018 if (err != 0) { 1019 if (err == -EMSGSIZE) 1020 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev); 1021 return -1; 1022 } 1023 1024 return 0; 1025} 1026 1027static int 1028ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1029{ 1030 struct ip6_tnl *t = netdev_priv(dev); 1031 struct net_device_stats *stats = &t->stat; 1032 int ret; 1033 1034 if (t->recursion++) { 1035 t->stat.collisions++; 1036 goto tx_err; 1037 } 1038 1039 switch (skb->protocol) { 1040 case __constant_htons(ETH_P_IP): 1041 ret = ip4ip6_tnl_xmit(skb, dev); 1042 break; 1043 case __constant_htons(ETH_P_IPV6): 1044 ret = ip6ip6_tnl_xmit(skb, dev); 1045 break; 1046 default: 1047 goto tx_err; 1048 } 1049 1050 if (ret < 0) 1051 goto tx_err; 1052 1053 t->recursion--; 1054 return 0; 1055 1056tx_err: 1057 stats->tx_errors++; 1058 stats->tx_dropped++; 1059 kfree_skb(skb); 1060 t->recursion--; 1061 return 0; 1062} 1063 1064static void ip6_tnl_set_cap(struct ip6_tnl *t) 1065{ 1066 struct ip6_tnl_parm *p = &t->parms; 1067 int ltype = ipv6_addr_type(&p->laddr); 1068 int rtype = ipv6_addr_type(&p->raddr); 1069 1070 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV); 1071 1072 if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1073 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1074 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 1075 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 1076 if (ltype&IPV6_ADDR_UNICAST) 1077 p->flags |= IP6_TNL_F_CAP_XMIT; 1078 if (rtype&IPV6_ADDR_UNICAST) 1079 p->flags |= IP6_TNL_F_CAP_RCV; 1080 } 1081} 1082 1083static void ip6_tnl_link_config(struct ip6_tnl *t) 1084{ 1085 struct net_device *dev = t->dev; 1086 struct ip6_tnl_parm *p = &t->parms; 1087 struct flowi *fl = &t->fl; 1088 1089 memcpy(&dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1090 memcpy(&dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1091 1092 /* Set up flowi template */ 1093 ipv6_addr_copy(&fl->fl6_src, &p->laddr); 1094 ipv6_addr_copy(&fl->fl6_dst, &p->raddr); 1095 fl->oif = p->link; 1096 fl->fl6_flowlabel = 0; 1097 1098 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1099 fl->fl6_flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1100 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1101 fl->fl6_flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1102 1103 ip6_tnl_set_cap(t); 1104 1105 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1106 dev->flags |= IFF_POINTOPOINT; 1107 else 1108 dev->flags &= ~IFF_POINTOPOINT; 1109 1110 dev->iflink = p->link; 1111 1112 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1113 int strict = (ipv6_addr_type(&p->raddr) & 1114 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1115 1116 struct rt6_info *rt = rt6_lookup(&p->raddr, &p->laddr, 1117 p->link, strict); 1118 1119 if (rt == NULL) 1120 return; 1121 1122 if (rt->rt6i_dev) { 1123 dev->hard_header_len = rt->rt6i_dev->hard_header_len + 1124 sizeof (struct ipv6hdr); 1125 1126 dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr); 1127 1128 if (dev->mtu < IPV6_MIN_MTU) 1129 dev->mtu = IPV6_MIN_MTU; 1130 } 1131 dst_release(&rt->u.dst); 1132 } 1133} 1134 1135/** 1136 * ip6_tnl_change - update the tunnel parameters 1137 * @t: tunnel to be changed 1138 * @p: tunnel configuration parameters 1139 * @active: != 0 if tunnel is ready for use 1140 * 1141 * Description: 1142 * ip6_tnl_change() updates the tunnel parameters 1143 **/ 1144 1145static int 1146ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p) 1147{ 1148 ipv6_addr_copy(&t->parms.laddr, &p->laddr); 1149 ipv6_addr_copy(&t->parms.raddr, &p->raddr); 1150 t->parms.flags = p->flags; 1151 t->parms.hop_limit = p->hop_limit; 1152 t->parms.encap_limit = p->encap_limit; 1153 t->parms.flowinfo = p->flowinfo; 1154 t->parms.link = p->link; 1155 t->parms.proto = p->proto; 1156 ip6_tnl_dst_reset(t); 1157 ip6_tnl_link_config(t); 1158 return 0; 1159} 1160 1161/** 1162 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1163 * @dev: virtual device associated with tunnel 1164 * @ifr: parameters passed from userspace 1165 * @cmd: command to be performed 1166 * 1167 * Description: 1168 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1169 * from userspace. 1170 * 1171 * The possible commands are the following: 1172 * %SIOCGETTUNNEL: get tunnel parameters for device 1173 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1174 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1175 * %SIOCDELTUNNEL: delete tunnel 1176 * 1177 * The fallback device "ip6tnl0", created during module 1178 * initialization, can be used for creating other tunnel devices. 1179 * 1180 * Return: 1181 * 0 on success, 1182 * %-EFAULT if unable to copy data to or from userspace, 1183 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1184 * %-EINVAL if passed tunnel parameters are invalid, 1185 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1186 * %-ENODEV if attempting to change or delete a nonexisting device 1187 **/ 1188 1189static int 1190ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1191{ 1192 int err = 0; 1193 struct ip6_tnl_parm p; 1194 struct ip6_tnl *t = NULL; 1195 1196 switch (cmd) { 1197 case SIOCGETTUNNEL: 1198 if (dev == ip6_fb_tnl_dev) { 1199 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) { 1200 err = -EFAULT; 1201 break; 1202 } 1203 t = ip6_tnl_locate(&p, 0); 1204 } 1205 if (t == NULL) 1206 t = netdev_priv(dev); 1207 memcpy(&p, &t->parms, sizeof (p)); 1208 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) { 1209 err = -EFAULT; 1210 } 1211 break; 1212 case SIOCADDTUNNEL: 1213 case SIOCCHGTUNNEL: 1214 err = -EPERM; 1215 if (!capable(CAP_NET_ADMIN)) 1216 break; 1217 err = -EFAULT; 1218 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1219 break; 1220 err = -EINVAL; 1221 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1222 p.proto != 0) 1223 break; 1224 t = ip6_tnl_locate(&p, cmd == SIOCADDTUNNEL); 1225 if (dev != ip6_fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 1226 if (t != NULL) { 1227 if (t->dev != dev) { 1228 err = -EEXIST; 1229 break; 1230 } 1231 } else 1232 t = netdev_priv(dev); 1233 1234 ip6_tnl_unlink(t); 1235 err = ip6_tnl_change(t, &p); 1236 ip6_tnl_link(t); 1237 netdev_state_change(dev); 1238 } 1239 if (t) { 1240 err = 0; 1241 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p))) 1242 err = -EFAULT; 1243 1244 } else 1245 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1246 break; 1247 case SIOCDELTUNNEL: 1248 err = -EPERM; 1249 if (!capable(CAP_NET_ADMIN)) 1250 break; 1251 1252 if (dev == ip6_fb_tnl_dev) { 1253 err = -EFAULT; 1254 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1255 break; 1256 err = -ENOENT; 1257 if ((t = ip6_tnl_locate(&p, 0)) == NULL) 1258 break; 1259 err = -EPERM; 1260 if (t->dev == ip6_fb_tnl_dev) 1261 break; 1262 dev = t->dev; 1263 } 1264 err = 0; 1265 unregister_netdevice(dev); 1266 break; 1267 default: 1268 err = -EINVAL; 1269 } 1270 return err; 1271} 1272 1273/** 1274 * ip6_tnl_get_stats - return the stats for tunnel device 1275 * @dev: virtual device associated with tunnel 1276 * 1277 * Return: stats for device 1278 **/ 1279 1280static struct net_device_stats * 1281ip6_tnl_get_stats(struct net_device *dev) 1282{ 1283 return &(((struct ip6_tnl *)netdev_priv(dev))->stat); 1284} 1285 1286/** 1287 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1288 * @dev: virtual device associated with tunnel 1289 * @new_mtu: the new mtu 1290 * 1291 * Return: 1292 * 0 on success, 1293 * %-EINVAL if mtu too small 1294 **/ 1295 1296static int 1297ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1298{ 1299 if (new_mtu < IPV6_MIN_MTU) { 1300 return -EINVAL; 1301 } 1302 dev->mtu = new_mtu; 1303 return 0; 1304} 1305 1306/** 1307 * ip6_tnl_dev_setup - setup virtual tunnel device 1308 * @dev: virtual device associated with tunnel 1309 * 1310 * Description: 1311 * Initialize function pointers and device parameters 1312 **/ 1313 1314static void ip6_tnl_dev_setup(struct net_device *dev) 1315{ 1316 SET_MODULE_OWNER(dev); 1317 dev->uninit = ip6_tnl_dev_uninit; 1318 dev->destructor = free_netdev; 1319 dev->hard_start_xmit = ip6_tnl_xmit; 1320 dev->get_stats = ip6_tnl_get_stats; 1321 dev->do_ioctl = ip6_tnl_ioctl; 1322 dev->change_mtu = ip6_tnl_change_mtu; 1323 1324 dev->type = ARPHRD_TUNNEL6; 1325 dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr); 1326 dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr); 1327 dev->flags |= IFF_NOARP; 1328 dev->addr_len = sizeof(struct in6_addr); 1329} 1330 1331 1332/** 1333 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1334 * @dev: virtual device associated with tunnel 1335 **/ 1336 1337static inline void 1338ip6_tnl_dev_init_gen(struct net_device *dev) 1339{ 1340 struct ip6_tnl *t = netdev_priv(dev); 1341 t->dev = dev; 1342 strcpy(t->parms.name, dev->name); 1343} 1344 1345/** 1346 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1347 * @dev: virtual device associated with tunnel 1348 **/ 1349 1350static int 1351ip6_tnl_dev_init(struct net_device *dev) 1352{ 1353 struct ip6_tnl *t = netdev_priv(dev); 1354 ip6_tnl_dev_init_gen(dev); 1355 ip6_tnl_link_config(t); 1356 return 0; 1357} 1358 1359/** 1360 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1361 * @dev: fallback device 1362 * 1363 * Return: 0 1364 **/ 1365 1366static int 1367ip6_fb_tnl_dev_init(struct net_device *dev) 1368{ 1369 struct ip6_tnl *t = netdev_priv(dev); 1370 ip6_tnl_dev_init_gen(dev); 1371 t->parms.proto = IPPROTO_IPV6; 1372 dev_hold(dev); 1373 tnls_wc[0] = t; 1374 return 0; 1375} 1376 1377static struct xfrm6_tunnel ip4ip6_handler = { 1378 .handler = ip4ip6_rcv, 1379 .err_handler = ip4ip6_err, 1380 .priority = 1, 1381}; 1382 1383static struct xfrm6_tunnel ip6ip6_handler = { 1384 .handler = ip6ip6_rcv, 1385 .err_handler = ip6ip6_err, 1386 .priority = 1, 1387}; 1388 1389/** 1390 * ip6_tunnel_init - register protocol and reserve needed resources 1391 * 1392 * Return: 0 on success 1393 **/ 1394 1395static int __init ip6_tunnel_init(void) 1396{ 1397 int err; 1398 1399 if (xfrm6_tunnel_register(&ip4ip6_handler, AF_INET)) { 1400 printk(KERN_ERR "ip6_tunnel init: can't register ip4ip6\n"); 1401 err = -EAGAIN; 1402 goto out; 1403 } 1404 1405 if (xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6)) { 1406 printk(KERN_ERR "ip6_tunnel init: can't register ip6ip6\n"); 1407 err = -EAGAIN; 1408 goto unreg_ip4ip6; 1409 } 1410 ip6_fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 1411 ip6_tnl_dev_setup); 1412 1413 if (!ip6_fb_tnl_dev) { 1414 err = -ENOMEM; 1415 goto fail; 1416 } 1417 ip6_fb_tnl_dev->init = ip6_fb_tnl_dev_init; 1418 1419 if ((err = register_netdev(ip6_fb_tnl_dev))) { 1420 free_netdev(ip6_fb_tnl_dev); 1421 goto fail; 1422 } 1423 return 0; 1424fail: 1425 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 1426unreg_ip4ip6: 1427 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 1428out: 1429 return err; 1430} 1431 1432static void __exit ip6_tnl_destroy_tunnels(void) 1433{ 1434 int h; 1435 struct ip6_tnl *t; 1436 1437 for (h = 0; h < HASH_SIZE; h++) { 1438 while ((t = tnls_r_l[h]) != NULL) 1439 unregister_netdevice(t->dev); 1440 } 1441 1442 t = tnls_wc[0]; 1443 unregister_netdevice(t->dev); 1444} 1445 1446/** 1447 * ip6_tunnel_cleanup - free resources and unregister protocol 1448 **/ 1449 1450static void __exit ip6_tunnel_cleanup(void) 1451{ 1452 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 1453 printk(KERN_INFO "ip6_tunnel close: can't deregister ip4ip6\n"); 1454 1455 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 1456 printk(KERN_INFO "ip6_tunnel close: can't deregister ip6ip6\n"); 1457 1458 rtnl_lock(); 1459 ip6_tnl_destroy_tunnels(); 1460 rtnl_unlock(); 1461} 1462 1463module_init(ip6_tunnel_init); 1464module_exit(ip6_tunnel_cleanup); 1465