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 #include <net/net_namespace.h> 56 #include <net/netns/generic.h> 57 58 MODULE_AUTHOR("Ville Nuorvala"); 59 MODULE_DESCRIPTION("IPv6 tunneling device"); 60 MODULE_LICENSE("GPL"); 61 62 #define IPV6_TLV_TEL_DST_SIZE 8 63 64 #ifdef IP6_TNL_DEBUG 65 #define IP6_TNL_TRACE(x...) printk(KERN_DEBUG "%s:" x "\n", __func__) 66 #else 67 #define IP6_TNL_TRACE(x...) do {;} while(0) 68 #endif 69 70 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) 71 #define IPV6_TCLASS_SHIFT 20 72 73 #define HASH_SIZE 32 74 75 #define HASH(addr) ((__force u32)((addr)->s6_addr32[0] ^ (addr)->s6_addr32[1] ^ \ 76 (addr)->s6_addr32[2] ^ (addr)->s6_addr32[3]) & \ 77 (HASH_SIZE - 1)) 78 79 static int ip6_fb_tnl_dev_init(struct net_device *dev); 80 static int ip6_tnl_dev_init(struct net_device *dev); 81 static void ip6_tnl_dev_setup(struct net_device *dev); 82 83 static int ip6_tnl_net_id; 84 struct ip6_tnl_net { 85 /* the IPv6 tunnel fallback device */ 86 struct net_device *fb_tnl_dev; 87 /* lists for storing tunnels in use */ 88 struct ip6_tnl *tnls_r_l[HASH_SIZE]; 89 struct ip6_tnl *tnls_wc[1]; 90 struct ip6_tnl **tnls[2]; 91 }; 92 93 /* lock for the tunnel lists */ 94 static DEFINE_RWLOCK(ip6_tnl_lock); 95 96 static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t) 97 { 98 struct dst_entry *dst = t->dst_cache; 99 100 if (dst && dst->obsolete && 101 dst->ops->check(dst, t->dst_cookie) == NULL) { 102 t->dst_cache = NULL; 103 dst_release(dst); 104 return NULL; 105 } 106 107 return dst; 108 } 109 110 static inline void ip6_tnl_dst_reset(struct ip6_tnl *t) 111 { 112 dst_release(t->dst_cache); 113 t->dst_cache = NULL; 114 } 115 116 static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst) 117 { 118 struct rt6_info *rt = (struct rt6_info *) dst; 119 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; 120 dst_release(t->dst_cache); 121 t->dst_cache = dst; 122 } 123 124 /** 125 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses 126 * @remote: the address of the tunnel exit-point 127 * @local: the address of the tunnel entry-point 128 * 129 * Return: 130 * tunnel matching given end-points if found, 131 * else fallback tunnel if its device is up, 132 * else %NULL 133 **/ 134 135 static struct ip6_tnl * 136 ip6_tnl_lookup(struct net *net, struct in6_addr *remote, struct in6_addr *local) 137 { 138 unsigned h0 = HASH(remote); 139 unsigned h1 = HASH(local); 140 struct ip6_tnl *t; 141 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 142 143 for (t = ip6n->tnls_r_l[h0 ^ h1]; t; t = t->next) { 144 if (ipv6_addr_equal(local, &t->parms.laddr) && 145 ipv6_addr_equal(remote, &t->parms.raddr) && 146 (t->dev->flags & IFF_UP)) 147 return t; 148 } 149 if ((t = ip6n->tnls_wc[0]) != NULL && (t->dev->flags & IFF_UP)) 150 return t; 151 152 return NULL; 153 } 154 155 /** 156 * ip6_tnl_bucket - get head of list matching given tunnel parameters 157 * @p: parameters containing tunnel end-points 158 * 159 * Description: 160 * ip6_tnl_bucket() returns the head of the list matching the 161 * &struct in6_addr entries laddr and raddr in @p. 162 * 163 * Return: head of IPv6 tunnel list 164 **/ 165 166 static struct ip6_tnl ** 167 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, struct ip6_tnl_parm *p) 168 { 169 struct in6_addr *remote = &p->raddr; 170 struct in6_addr *local = &p->laddr; 171 unsigned h = 0; 172 int prio = 0; 173 174 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 175 prio = 1; 176 h = HASH(remote) ^ HASH(local); 177 } 178 return &ip6n->tnls[prio][h]; 179 } 180 181 /** 182 * ip6_tnl_link - add tunnel to hash table 183 * @t: tunnel to be added 184 **/ 185 186 static void 187 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 188 { 189 struct ip6_tnl **tp = ip6_tnl_bucket(ip6n, &t->parms); 190 191 t->next = *tp; 192 write_lock_bh(&ip6_tnl_lock); 193 *tp = t; 194 write_unlock_bh(&ip6_tnl_lock); 195 } 196 197 /** 198 * ip6_tnl_unlink - remove tunnel from hash table 199 * @t: tunnel to be removed 200 **/ 201 202 static void 203 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) 204 { 205 struct ip6_tnl **tp; 206 207 for (tp = ip6_tnl_bucket(ip6n, &t->parms); *tp; tp = &(*tp)->next) { 208 if (t == *tp) { 209 write_lock_bh(&ip6_tnl_lock); 210 *tp = t->next; 211 write_unlock_bh(&ip6_tnl_lock); 212 break; 213 } 214 } 215 } 216 217 /** 218 * ip6_tnl_create() - create a new tunnel 219 * @p: tunnel parameters 220 * @pt: pointer to new tunnel 221 * 222 * Description: 223 * Create tunnel matching given parameters. 224 * 225 * Return: 226 * created tunnel or NULL 227 **/ 228 229 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct ip6_tnl_parm *p) 230 { 231 struct net_device *dev; 232 struct ip6_tnl *t; 233 char name[IFNAMSIZ]; 234 int err; 235 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 236 237 if (p->name[0]) 238 strlcpy(name, p->name, IFNAMSIZ); 239 else 240 sprintf(name, "ip6tnl%%d"); 241 242 dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup); 243 if (dev == NULL) 244 goto failed; 245 246 dev_net_set(dev, net); 247 248 if (strchr(name, '%')) { 249 if (dev_alloc_name(dev, name) < 0) 250 goto failed_free; 251 } 252 253 t = netdev_priv(dev); 254 dev->init = ip6_tnl_dev_init; 255 t->parms = *p; 256 257 if ((err = register_netdevice(dev)) < 0) 258 goto failed_free; 259 260 dev_hold(dev); 261 ip6_tnl_link(ip6n, t); 262 return t; 263 264 failed_free: 265 free_netdev(dev); 266 failed: 267 return NULL; 268 } 269 270 /** 271 * ip6_tnl_locate - find or create tunnel matching given parameters 272 * @p: tunnel parameters 273 * @create: != 0 if allowed to create new tunnel if no match found 274 * 275 * Description: 276 * ip6_tnl_locate() first tries to locate an existing tunnel 277 * based on @parms. If this is unsuccessful, but @create is set a new 278 * tunnel device is created and registered for use. 279 * 280 * Return: 281 * matching tunnel or NULL 282 **/ 283 284 static struct ip6_tnl *ip6_tnl_locate(struct net *net, 285 struct ip6_tnl_parm *p, int create) 286 { 287 struct in6_addr *remote = &p->raddr; 288 struct in6_addr *local = &p->laddr; 289 struct ip6_tnl *t; 290 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 291 292 for (t = *ip6_tnl_bucket(ip6n, p); t; t = t->next) { 293 if (ipv6_addr_equal(local, &t->parms.laddr) && 294 ipv6_addr_equal(remote, &t->parms.raddr)) 295 return t; 296 } 297 if (!create) 298 return NULL; 299 return ip6_tnl_create(net, p); 300 } 301 302 /** 303 * ip6_tnl_dev_uninit - tunnel device uninitializer 304 * @dev: the device to be destroyed 305 * 306 * Description: 307 * ip6_tnl_dev_uninit() removes tunnel from its list 308 **/ 309 310 static void 311 ip6_tnl_dev_uninit(struct net_device *dev) 312 { 313 struct ip6_tnl *t = netdev_priv(dev); 314 struct net *net = dev_net(dev); 315 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 316 317 if (dev == ip6n->fb_tnl_dev) { 318 write_lock_bh(&ip6_tnl_lock); 319 ip6n->tnls_wc[0] = NULL; 320 write_unlock_bh(&ip6_tnl_lock); 321 } else { 322 ip6_tnl_unlink(ip6n, t); 323 } 324 ip6_tnl_dst_reset(t); 325 dev_put(dev); 326 } 327 328 /** 329 * parse_tvl_tnl_enc_lim - handle encapsulation limit option 330 * @skb: received socket buffer 331 * 332 * Return: 333 * 0 if none was found, 334 * else index to encapsulation limit 335 **/ 336 337 static __u16 338 parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw) 339 { 340 struct ipv6hdr *ipv6h = (struct ipv6hdr *) raw; 341 __u8 nexthdr = ipv6h->nexthdr; 342 __u16 off = sizeof (*ipv6h); 343 344 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { 345 __u16 optlen = 0; 346 struct ipv6_opt_hdr *hdr; 347 if (raw + off + sizeof (*hdr) > skb->data && 348 !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr))) 349 break; 350 351 hdr = (struct ipv6_opt_hdr *) (raw + off); 352 if (nexthdr == NEXTHDR_FRAGMENT) { 353 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; 354 if (frag_hdr->frag_off) 355 break; 356 optlen = 8; 357 } else if (nexthdr == NEXTHDR_AUTH) { 358 optlen = (hdr->hdrlen + 2) << 2; 359 } else { 360 optlen = ipv6_optlen(hdr); 361 } 362 if (nexthdr == NEXTHDR_DEST) { 363 __u16 i = off + 2; 364 while (1) { 365 struct ipv6_tlv_tnl_enc_lim *tel; 366 367 /* No more room for encapsulation limit */ 368 if (i + sizeof (*tel) > off + optlen) 369 break; 370 371 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i]; 372 /* return index of option if found and valid */ 373 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && 374 tel->length == 1) 375 return i; 376 /* else jump to next option */ 377 if (tel->type) 378 i += tel->length + 2; 379 else 380 i++; 381 } 382 } 383 nexthdr = hdr->nexthdr; 384 off += optlen; 385 } 386 return 0; 387 } 388 389 /** 390 * ip6_tnl_err - tunnel error handler 391 * 392 * Description: 393 * ip6_tnl_err() should handle errors in the tunnel according 394 * to the specifications in RFC 2473. 395 **/ 396 397 static int 398 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, 399 int *type, int *code, int *msg, __u32 *info, int offset) 400 { 401 struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data; 402 struct ip6_tnl *t; 403 int rel_msg = 0; 404 int rel_type = ICMPV6_DEST_UNREACH; 405 int rel_code = ICMPV6_ADDR_UNREACH; 406 __u32 rel_info = 0; 407 __u16 len; 408 int err = -ENOENT; 409 410 /* If the packet doesn't contain the original IPv6 header we are 411 in trouble since we might need the source address for further 412 processing of the error. */ 413 414 read_lock(&ip6_tnl_lock); 415 if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, 416 &ipv6h->saddr)) == NULL) 417 goto out; 418 419 if (t->parms.proto != ipproto && t->parms.proto != 0) 420 goto out; 421 422 err = 0; 423 424 switch (*type) { 425 __u32 teli; 426 struct ipv6_tlv_tnl_enc_lim *tel; 427 __u32 mtu; 428 case ICMPV6_DEST_UNREACH: 429 if (net_ratelimit()) 430 printk(KERN_WARNING 431 "%s: Path to destination invalid " 432 "or inactive!\n", t->parms.name); 433 rel_msg = 1; 434 break; 435 case ICMPV6_TIME_EXCEED: 436 if ((*code) == ICMPV6_EXC_HOPLIMIT) { 437 if (net_ratelimit()) 438 printk(KERN_WARNING 439 "%s: Too small hop limit or " 440 "routing loop in tunnel!\n", 441 t->parms.name); 442 rel_msg = 1; 443 } 444 break; 445 case ICMPV6_PARAMPROB: 446 teli = 0; 447 if ((*code) == ICMPV6_HDR_FIELD) 448 teli = parse_tlv_tnl_enc_lim(skb, skb->data); 449 450 if (teli && teli == *info - 2) { 451 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 452 if (tel->encap_limit == 0) { 453 if (net_ratelimit()) 454 printk(KERN_WARNING 455 "%s: Too small encapsulation " 456 "limit or routing loop in " 457 "tunnel!\n", t->parms.name); 458 rel_msg = 1; 459 } 460 } else if (net_ratelimit()) { 461 printk(KERN_WARNING 462 "%s: Recipient unable to parse tunneled " 463 "packet!\n ", t->parms.name); 464 } 465 break; 466 case ICMPV6_PKT_TOOBIG: 467 mtu = *info - offset; 468 if (mtu < IPV6_MIN_MTU) 469 mtu = IPV6_MIN_MTU; 470 t->dev->mtu = mtu; 471 472 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) { 473 rel_type = ICMPV6_PKT_TOOBIG; 474 rel_code = 0; 475 rel_info = mtu; 476 rel_msg = 1; 477 } 478 break; 479 } 480 481 *type = rel_type; 482 *code = rel_code; 483 *info = rel_info; 484 *msg = rel_msg; 485 486 out: 487 read_unlock(&ip6_tnl_lock); 488 return err; 489 } 490 491 static int 492 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 493 int type, int code, int offset, __be32 info) 494 { 495 int rel_msg = 0; 496 int rel_type = type; 497 int rel_code = code; 498 __u32 rel_info = ntohl(info); 499 int err; 500 struct sk_buff *skb2; 501 struct iphdr *eiph; 502 struct flowi fl; 503 struct rtable *rt; 504 505 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, 506 &rel_msg, &rel_info, offset); 507 if (err < 0) 508 return err; 509 510 if (rel_msg == 0) 511 return 0; 512 513 switch (rel_type) { 514 case ICMPV6_DEST_UNREACH: 515 if (rel_code != ICMPV6_ADDR_UNREACH) 516 return 0; 517 rel_type = ICMP_DEST_UNREACH; 518 rel_code = ICMP_HOST_UNREACH; 519 break; 520 case ICMPV6_PKT_TOOBIG: 521 if (rel_code != 0) 522 return 0; 523 rel_type = ICMP_DEST_UNREACH; 524 rel_code = ICMP_FRAG_NEEDED; 525 break; 526 default: 527 return 0; 528 } 529 530 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) 531 return 0; 532 533 skb2 = skb_clone(skb, GFP_ATOMIC); 534 if (!skb2) 535 return 0; 536 537 dst_release(skb2->dst); 538 skb2->dst = NULL; 539 skb_pull(skb2, offset); 540 skb_reset_network_header(skb2); 541 eiph = ip_hdr(skb2); 542 543 /* Try to guess incoming interface */ 544 memset(&fl, 0, sizeof(fl)); 545 fl.fl4_dst = eiph->saddr; 546 fl.fl4_tos = RT_TOS(eiph->tos); 547 fl.proto = IPPROTO_IPIP; 548 if (ip_route_output_key(dev_net(skb->dev), &rt, &fl)) 549 goto out; 550 551 skb2->dev = rt->u.dst.dev; 552 553 /* route "incoming" packet */ 554 if (rt->rt_flags & RTCF_LOCAL) { 555 ip_rt_put(rt); 556 rt = NULL; 557 fl.fl4_dst = eiph->daddr; 558 fl.fl4_src = eiph->saddr; 559 fl.fl4_tos = eiph->tos; 560 if (ip_route_output_key(dev_net(skb->dev), &rt, &fl) || 561 rt->u.dst.dev->type != ARPHRD_TUNNEL) { 562 ip_rt_put(rt); 563 goto out; 564 } 565 skb2->dst = (struct dst_entry *)rt; 566 } else { 567 ip_rt_put(rt); 568 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, 569 skb2->dev) || 570 skb2->dst->dev->type != ARPHRD_TUNNEL) 571 goto out; 572 } 573 574 /* change mtu on this route */ 575 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { 576 if (rel_info > dst_mtu(skb2->dst)) 577 goto out; 578 579 skb2->dst->ops->update_pmtu(skb2->dst, rel_info); 580 } 581 582 icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); 583 584 out: 585 kfree_skb(skb2); 586 return 0; 587 } 588 589 static int 590 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 591 int type, int code, int offset, __be32 info) 592 { 593 int rel_msg = 0; 594 int rel_type = type; 595 int rel_code = code; 596 __u32 rel_info = ntohl(info); 597 int err; 598 599 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, 600 &rel_msg, &rel_info, offset); 601 if (err < 0) 602 return err; 603 604 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { 605 struct rt6_info *rt; 606 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 607 608 if (!skb2) 609 return 0; 610 611 dst_release(skb2->dst); 612 skb2->dst = NULL; 613 skb_pull(skb2, offset); 614 skb_reset_network_header(skb2); 615 616 /* Try to guess incoming interface */ 617 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, 618 NULL, 0, 0); 619 620 if (rt && rt->rt6i_dev) 621 skb2->dev = rt->rt6i_dev; 622 623 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev); 624 625 if (rt) 626 dst_release(&rt->u.dst); 627 628 kfree_skb(skb2); 629 } 630 631 return 0; 632 } 633 634 static void ip4ip6_dscp_ecn_decapsulate(struct ip6_tnl *t, 635 struct ipv6hdr *ipv6h, 636 struct sk_buff *skb) 637 { 638 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; 639 640 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 641 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); 642 643 if (INET_ECN_is_ce(dsfield)) 644 IP_ECN_set_ce(ip_hdr(skb)); 645 } 646 647 static void ip6ip6_dscp_ecn_decapsulate(struct ip6_tnl *t, 648 struct ipv6hdr *ipv6h, 649 struct sk_buff *skb) 650 { 651 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) 652 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); 653 654 if (INET_ECN_is_ce(ipv6_get_dsfield(ipv6h))) 655 IP6_ECN_set_ce(ipv6_hdr(skb)); 656 } 657 658 static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t) 659 { 660 struct ip6_tnl_parm *p = &t->parms; 661 int ret = 0; 662 struct net *net = dev_net(t->dev); 663 664 if (p->flags & IP6_TNL_F_CAP_RCV) { 665 struct net_device *ldev = NULL; 666 667 if (p->link) 668 ldev = dev_get_by_index(net, p->link); 669 670 if ((ipv6_addr_is_multicast(&p->laddr) || 671 likely(ipv6_chk_addr(net, &p->laddr, ldev, 0))) && 672 likely(!ipv6_chk_addr(net, &p->raddr, NULL, 0))) 673 ret = 1; 674 675 if (ldev) 676 dev_put(ldev); 677 } 678 return ret; 679 } 680 681 /** 682 * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally 683 * @skb: received socket buffer 684 * @protocol: ethernet protocol ID 685 * @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN 686 * 687 * Return: 0 688 **/ 689 690 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, 691 __u8 ipproto, 692 void (*dscp_ecn_decapsulate)(struct ip6_tnl *t, 693 struct ipv6hdr *ipv6h, 694 struct sk_buff *skb)) 695 { 696 struct ip6_tnl *t; 697 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 698 699 read_lock(&ip6_tnl_lock); 700 701 if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, 702 &ipv6h->daddr)) != NULL) { 703 if (t->parms.proto != ipproto && t->parms.proto != 0) { 704 read_unlock(&ip6_tnl_lock); 705 goto discard; 706 } 707 708 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 709 read_unlock(&ip6_tnl_lock); 710 goto discard; 711 } 712 713 if (!ip6_tnl_rcv_ctl(t)) { 714 t->stat.rx_dropped++; 715 read_unlock(&ip6_tnl_lock); 716 goto discard; 717 } 718 secpath_reset(skb); 719 skb->mac_header = skb->network_header; 720 skb_reset_network_header(skb); 721 skb->protocol = htons(protocol); 722 skb->pkt_type = PACKET_HOST; 723 memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); 724 skb->dev = t->dev; 725 dst_release(skb->dst); 726 skb->dst = NULL; 727 nf_reset(skb); 728 729 dscp_ecn_decapsulate(t, ipv6h, skb); 730 731 t->stat.rx_packets++; 732 t->stat.rx_bytes += skb->len; 733 netif_rx(skb); 734 read_unlock(&ip6_tnl_lock); 735 return 0; 736 } 737 read_unlock(&ip6_tnl_lock); 738 return 1; 739 740 discard: 741 kfree_skb(skb); 742 return 0; 743 } 744 745 static int ip4ip6_rcv(struct sk_buff *skb) 746 { 747 return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP, 748 ip4ip6_dscp_ecn_decapsulate); 749 } 750 751 static int ip6ip6_rcv(struct sk_buff *skb) 752 { 753 return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6, 754 ip6ip6_dscp_ecn_decapsulate); 755 } 756 757 struct ipv6_tel_txoption { 758 struct ipv6_txoptions ops; 759 __u8 dst_opt[8]; 760 }; 761 762 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 763 { 764 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 765 766 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 767 opt->dst_opt[3] = 1; 768 opt->dst_opt[4] = encap_limit; 769 opt->dst_opt[5] = IPV6_TLV_PADN; 770 opt->dst_opt[6] = 1; 771 772 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 773 opt->ops.opt_nflen = 8; 774 } 775 776 /** 777 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 778 * @t: the outgoing tunnel device 779 * @hdr: IPv6 header from the incoming packet 780 * 781 * Description: 782 * Avoid trivial tunneling loop by checking that tunnel exit-point 783 * doesn't match source of incoming packet. 784 * 785 * Return: 786 * 1 if conflict, 787 * 0 else 788 **/ 789 790 static inline int 791 ip6_tnl_addr_conflict(struct ip6_tnl *t, struct ipv6hdr *hdr) 792 { 793 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 794 } 795 796 static inline int ip6_tnl_xmit_ctl(struct ip6_tnl *t) 797 { 798 struct ip6_tnl_parm *p = &t->parms; 799 int ret = 0; 800 struct net *net = dev_net(t->dev); 801 802 if (p->flags & IP6_TNL_F_CAP_XMIT) { 803 struct net_device *ldev = NULL; 804 805 if (p->link) 806 ldev = dev_get_by_index(net, p->link); 807 808 if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0))) 809 printk(KERN_WARNING 810 "%s xmit: Local address not yet configured!\n", 811 p->name); 812 else if (!ipv6_addr_is_multicast(&p->raddr) && 813 unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0))) 814 printk(KERN_WARNING 815 "%s xmit: Routing loop! " 816 "Remote address found on this node!\n", 817 p->name); 818 else 819 ret = 1; 820 if (ldev) 821 dev_put(ldev); 822 } 823 return ret; 824 } 825 /** 826 * ip6_tnl_xmit2 - encapsulate packet and send 827 * @skb: the outgoing socket buffer 828 * @dev: the outgoing tunnel device 829 * @dsfield: dscp code for outer header 830 * @fl: flow of tunneled packet 831 * @encap_limit: encapsulation limit 832 * @pmtu: Path MTU is stored if packet is too big 833 * 834 * Description: 835 * Build new header and do some sanity checks on the packet before sending 836 * it. 837 * 838 * Return: 839 * 0 on success 840 * -1 fail 841 * %-EMSGSIZE message too big. return mtu in this case. 842 **/ 843 844 static int ip6_tnl_xmit2(struct sk_buff *skb, 845 struct net_device *dev, 846 __u8 dsfield, 847 struct flowi *fl, 848 int encap_limit, 849 __u32 *pmtu) 850 { 851 struct ip6_tnl *t = netdev_priv(dev); 852 struct net_device_stats *stats = &t->stat; 853 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 854 struct ipv6_tel_txoption opt; 855 struct dst_entry *dst; 856 struct net_device *tdev; 857 int mtu; 858 unsigned int max_headroom = sizeof(struct ipv6hdr); 859 u8 proto; 860 int err = -1; 861 int pkt_len; 862 863 if ((dst = ip6_tnl_dst_check(t)) != NULL) 864 dst_hold(dst); 865 else { 866 dst = ip6_route_output(dev_net(dev), NULL, fl); 867 868 if (dst->error || xfrm_lookup(&dst, fl, NULL, 0) < 0) 869 goto tx_err_link_failure; 870 } 871 872 tdev = dst->dev; 873 874 if (tdev == dev) { 875 stats->collisions++; 876 if (net_ratelimit()) 877 printk(KERN_WARNING 878 "%s: Local routing loop detected!\n", 879 t->parms.name); 880 goto tx_err_dst_release; 881 } 882 mtu = dst_mtu(dst) - sizeof (*ipv6h); 883 if (encap_limit >= 0) { 884 max_headroom += 8; 885 mtu -= 8; 886 } 887 if (mtu < IPV6_MIN_MTU) 888 mtu = IPV6_MIN_MTU; 889 if (skb->dst) 890 skb->dst->ops->update_pmtu(skb->dst, mtu); 891 if (skb->len > mtu) { 892 *pmtu = mtu; 893 err = -EMSGSIZE; 894 goto tx_err_dst_release; 895 } 896 897 /* 898 * Okay, now see if we can stuff it in the buffer as-is. 899 */ 900 max_headroom += LL_RESERVED_SPACE(tdev); 901 902 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 903 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 904 struct sk_buff *new_skb; 905 906 if (!(new_skb = skb_realloc_headroom(skb, max_headroom))) 907 goto tx_err_dst_release; 908 909 if (skb->sk) 910 skb_set_owner_w(new_skb, skb->sk); 911 kfree_skb(skb); 912 skb = new_skb; 913 } 914 dst_release(skb->dst); 915 skb->dst = dst_clone(dst); 916 917 skb->transport_header = skb->network_header; 918 919 proto = fl->proto; 920 if (encap_limit >= 0) { 921 init_tel_txopt(&opt, encap_limit); 922 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 923 } 924 skb_push(skb, sizeof(struct ipv6hdr)); 925 skb_reset_network_header(skb); 926 ipv6h = ipv6_hdr(skb); 927 *(__be32*)ipv6h = fl->fl6_flowlabel | htonl(0x60000000); 928 dsfield = INET_ECN_encapsulate(0, dsfield); 929 ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield); 930 ipv6h->hop_limit = t->parms.hop_limit; 931 ipv6h->nexthdr = proto; 932 ipv6_addr_copy(&ipv6h->saddr, &fl->fl6_src); 933 ipv6_addr_copy(&ipv6h->daddr, &fl->fl6_dst); 934 nf_reset(skb); 935 pkt_len = skb->len; 936 err = ip6_local_out(skb); 937 938 if (net_xmit_eval(err) == 0) { 939 stats->tx_bytes += pkt_len; 940 stats->tx_packets++; 941 } else { 942 stats->tx_errors++; 943 stats->tx_aborted_errors++; 944 } 945 ip6_tnl_dst_store(t, dst); 946 return 0; 947 tx_err_link_failure: 948 stats->tx_carrier_errors++; 949 dst_link_failure(skb); 950 tx_err_dst_release: 951 dst_release(dst); 952 return err; 953 } 954 955 static inline int 956 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 957 { 958 struct ip6_tnl *t = netdev_priv(dev); 959 struct iphdr *iph = ip_hdr(skb); 960 int encap_limit = -1; 961 struct flowi fl; 962 __u8 dsfield; 963 __u32 mtu; 964 int err; 965 966 if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) || 967 !ip6_tnl_xmit_ctl(t)) 968 return -1; 969 970 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 971 encap_limit = t->parms.encap_limit; 972 973 memcpy(&fl, &t->fl, sizeof (fl)); 974 fl.proto = IPPROTO_IPIP; 975 976 dsfield = ipv4_get_dsfield(iph); 977 978 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 979 fl.fl6_flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 980 & IPV6_TCLASS_MASK; 981 982 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu); 983 if (err != 0) { 984 /* XXX: send ICMP error even if DF is not set. */ 985 if (err == -EMSGSIZE) 986 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 987 htonl(mtu)); 988 return -1; 989 } 990 991 return 0; 992 } 993 994 static inline int 995 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 996 { 997 struct ip6_tnl *t = netdev_priv(dev); 998 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 999 int encap_limit = -1; 1000 __u16 offset; 1001 struct flowi fl; 1002 __u8 dsfield; 1003 __u32 mtu; 1004 int err; 1005 1006 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 1007 !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h)) 1008 return -1; 1009 1010 offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb)); 1011 if (offset > 0) { 1012 struct ipv6_tlv_tnl_enc_lim *tel; 1013 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 1014 if (tel->encap_limit == 0) { 1015 icmpv6_send(skb, ICMPV6_PARAMPROB, 1016 ICMPV6_HDR_FIELD, offset + 2, skb->dev); 1017 return -1; 1018 } 1019 encap_limit = tel->encap_limit - 1; 1020 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1021 encap_limit = t->parms.encap_limit; 1022 1023 memcpy(&fl, &t->fl, sizeof (fl)); 1024 fl.proto = IPPROTO_IPV6; 1025 1026 dsfield = ipv6_get_dsfield(ipv6h); 1027 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) 1028 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 1029 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1030 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 1031 1032 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu); 1033 if (err != 0) { 1034 if (err == -EMSGSIZE) 1035 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev); 1036 return -1; 1037 } 1038 1039 return 0; 1040 } 1041 1042 static int 1043 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 1044 { 1045 struct ip6_tnl *t = netdev_priv(dev); 1046 struct net_device_stats *stats = &t->stat; 1047 int ret; 1048 1049 if (t->recursion++) { 1050 t->stat.collisions++; 1051 goto tx_err; 1052 } 1053 1054 switch (skb->protocol) { 1055 case __constant_htons(ETH_P_IP): 1056 ret = ip4ip6_tnl_xmit(skb, dev); 1057 break; 1058 case __constant_htons(ETH_P_IPV6): 1059 ret = ip6ip6_tnl_xmit(skb, dev); 1060 break; 1061 default: 1062 goto tx_err; 1063 } 1064 1065 if (ret < 0) 1066 goto tx_err; 1067 1068 t->recursion--; 1069 return 0; 1070 1071 tx_err: 1072 stats->tx_errors++; 1073 stats->tx_dropped++; 1074 kfree_skb(skb); 1075 t->recursion--; 1076 return 0; 1077 } 1078 1079 static void ip6_tnl_set_cap(struct ip6_tnl *t) 1080 { 1081 struct ip6_tnl_parm *p = &t->parms; 1082 int ltype = ipv6_addr_type(&p->laddr); 1083 int rtype = ipv6_addr_type(&p->raddr); 1084 1085 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV); 1086 1087 if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1088 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && 1089 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && 1090 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { 1091 if (ltype&IPV6_ADDR_UNICAST) 1092 p->flags |= IP6_TNL_F_CAP_XMIT; 1093 if (rtype&IPV6_ADDR_UNICAST) 1094 p->flags |= IP6_TNL_F_CAP_RCV; 1095 } 1096 } 1097 1098 static void ip6_tnl_link_config(struct ip6_tnl *t) 1099 { 1100 struct net_device *dev = t->dev; 1101 struct ip6_tnl_parm *p = &t->parms; 1102 struct flowi *fl = &t->fl; 1103 1104 memcpy(&dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1105 memcpy(&dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1106 1107 /* Set up flowi template */ 1108 ipv6_addr_copy(&fl->fl6_src, &p->laddr); 1109 ipv6_addr_copy(&fl->fl6_dst, &p->raddr); 1110 fl->oif = p->link; 1111 fl->fl6_flowlabel = 0; 1112 1113 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1114 fl->fl6_flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1115 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1116 fl->fl6_flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1117 1118 ip6_tnl_set_cap(t); 1119 1120 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) 1121 dev->flags |= IFF_POINTOPOINT; 1122 else 1123 dev->flags &= ~IFF_POINTOPOINT; 1124 1125 dev->iflink = p->link; 1126 1127 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1128 int strict = (ipv6_addr_type(&p->raddr) & 1129 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1130 1131 struct rt6_info *rt = rt6_lookup(dev_net(dev), 1132 &p->raddr, &p->laddr, 1133 p->link, strict); 1134 1135 if (rt == NULL) 1136 return; 1137 1138 if (rt->rt6i_dev) { 1139 dev->hard_header_len = rt->rt6i_dev->hard_header_len + 1140 sizeof (struct ipv6hdr); 1141 1142 dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr); 1143 1144 if (dev->mtu < IPV6_MIN_MTU) 1145 dev->mtu = IPV6_MIN_MTU; 1146 } 1147 dst_release(&rt->u.dst); 1148 } 1149 } 1150 1151 /** 1152 * ip6_tnl_change - update the tunnel parameters 1153 * @t: tunnel to be changed 1154 * @p: tunnel configuration parameters 1155 * @active: != 0 if tunnel is ready for use 1156 * 1157 * Description: 1158 * ip6_tnl_change() updates the tunnel parameters 1159 **/ 1160 1161 static int 1162 ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p) 1163 { 1164 ipv6_addr_copy(&t->parms.laddr, &p->laddr); 1165 ipv6_addr_copy(&t->parms.raddr, &p->raddr); 1166 t->parms.flags = p->flags; 1167 t->parms.hop_limit = p->hop_limit; 1168 t->parms.encap_limit = p->encap_limit; 1169 t->parms.flowinfo = p->flowinfo; 1170 t->parms.link = p->link; 1171 t->parms.proto = p->proto; 1172 ip6_tnl_dst_reset(t); 1173 ip6_tnl_link_config(t); 1174 return 0; 1175 } 1176 1177 /** 1178 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace 1179 * @dev: virtual device associated with tunnel 1180 * @ifr: parameters passed from userspace 1181 * @cmd: command to be performed 1182 * 1183 * Description: 1184 * ip6_tnl_ioctl() is used for managing IPv6 tunnels 1185 * from userspace. 1186 * 1187 * The possible commands are the following: 1188 * %SIOCGETTUNNEL: get tunnel parameters for device 1189 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 1190 * %SIOCCHGTUNNEL: change tunnel parameters to those given 1191 * %SIOCDELTUNNEL: delete tunnel 1192 * 1193 * The fallback device "ip6tnl0", created during module 1194 * initialization, can be used for creating other tunnel devices. 1195 * 1196 * Return: 1197 * 0 on success, 1198 * %-EFAULT if unable to copy data to or from userspace, 1199 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 1200 * %-EINVAL if passed tunnel parameters are invalid, 1201 * %-EEXIST if changing a tunnel's parameters would cause a conflict 1202 * %-ENODEV if attempting to change or delete a nonexisting device 1203 **/ 1204 1205 static int 1206 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 1207 { 1208 int err = 0; 1209 struct ip6_tnl_parm p; 1210 struct ip6_tnl *t = NULL; 1211 struct net *net = dev_net(dev); 1212 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1213 1214 switch (cmd) { 1215 case SIOCGETTUNNEL: 1216 if (dev == ip6n->fb_tnl_dev) { 1217 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) { 1218 err = -EFAULT; 1219 break; 1220 } 1221 t = ip6_tnl_locate(net, &p, 0); 1222 } 1223 if (t == NULL) 1224 t = netdev_priv(dev); 1225 memcpy(&p, &t->parms, sizeof (p)); 1226 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) { 1227 err = -EFAULT; 1228 } 1229 break; 1230 case SIOCADDTUNNEL: 1231 case SIOCCHGTUNNEL: 1232 err = -EPERM; 1233 if (!capable(CAP_NET_ADMIN)) 1234 break; 1235 err = -EFAULT; 1236 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1237 break; 1238 err = -EINVAL; 1239 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && 1240 p.proto != 0) 1241 break; 1242 t = ip6_tnl_locate(net, &p, cmd == SIOCADDTUNNEL); 1243 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 1244 if (t != NULL) { 1245 if (t->dev != dev) { 1246 err = -EEXIST; 1247 break; 1248 } 1249 } else 1250 t = netdev_priv(dev); 1251 1252 ip6_tnl_unlink(ip6n, t); 1253 err = ip6_tnl_change(t, &p); 1254 ip6_tnl_link(ip6n, t); 1255 netdev_state_change(dev); 1256 } 1257 if (t) { 1258 err = 0; 1259 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p))) 1260 err = -EFAULT; 1261 1262 } else 1263 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1264 break; 1265 case SIOCDELTUNNEL: 1266 err = -EPERM; 1267 if (!capable(CAP_NET_ADMIN)) 1268 break; 1269 1270 if (dev == ip6n->fb_tnl_dev) { 1271 err = -EFAULT; 1272 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) 1273 break; 1274 err = -ENOENT; 1275 if ((t = ip6_tnl_locate(net, &p, 0)) == NULL) 1276 break; 1277 err = -EPERM; 1278 if (t->dev == ip6n->fb_tnl_dev) 1279 break; 1280 dev = t->dev; 1281 } 1282 err = 0; 1283 unregister_netdevice(dev); 1284 break; 1285 default: 1286 err = -EINVAL; 1287 } 1288 return err; 1289 } 1290 1291 /** 1292 * ip6_tnl_get_stats - return the stats for tunnel device 1293 * @dev: virtual device associated with tunnel 1294 * 1295 * Return: stats for device 1296 **/ 1297 1298 static struct net_device_stats * 1299 ip6_tnl_get_stats(struct net_device *dev) 1300 { 1301 return &(((struct ip6_tnl *)netdev_priv(dev))->stat); 1302 } 1303 1304 /** 1305 * ip6_tnl_change_mtu - change mtu manually for tunnel device 1306 * @dev: virtual device associated with tunnel 1307 * @new_mtu: the new mtu 1308 * 1309 * Return: 1310 * 0 on success, 1311 * %-EINVAL if mtu too small 1312 **/ 1313 1314 static int 1315 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 1316 { 1317 if (new_mtu < IPV6_MIN_MTU) { 1318 return -EINVAL; 1319 } 1320 dev->mtu = new_mtu; 1321 return 0; 1322 } 1323 1324 /** 1325 * ip6_tnl_dev_setup - setup virtual tunnel device 1326 * @dev: virtual device associated with tunnel 1327 * 1328 * Description: 1329 * Initialize function pointers and device parameters 1330 **/ 1331 1332 static void ip6_tnl_dev_setup(struct net_device *dev) 1333 { 1334 dev->uninit = ip6_tnl_dev_uninit; 1335 dev->destructor = free_netdev; 1336 dev->hard_start_xmit = ip6_tnl_xmit; 1337 dev->get_stats = ip6_tnl_get_stats; 1338 dev->do_ioctl = ip6_tnl_ioctl; 1339 dev->change_mtu = ip6_tnl_change_mtu; 1340 1341 dev->type = ARPHRD_TUNNEL6; 1342 dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr); 1343 dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr); 1344 dev->flags |= IFF_NOARP; 1345 dev->addr_len = sizeof(struct in6_addr); 1346 dev->features |= NETIF_F_NETNS_LOCAL; 1347 } 1348 1349 1350 /** 1351 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices 1352 * @dev: virtual device associated with tunnel 1353 **/ 1354 1355 static inline void 1356 ip6_tnl_dev_init_gen(struct net_device *dev) 1357 { 1358 struct ip6_tnl *t = netdev_priv(dev); 1359 t->dev = dev; 1360 strcpy(t->parms.name, dev->name); 1361 } 1362 1363 /** 1364 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices 1365 * @dev: virtual device associated with tunnel 1366 **/ 1367 1368 static int 1369 ip6_tnl_dev_init(struct net_device *dev) 1370 { 1371 struct ip6_tnl *t = netdev_priv(dev); 1372 ip6_tnl_dev_init_gen(dev); 1373 ip6_tnl_link_config(t); 1374 return 0; 1375 } 1376 1377 /** 1378 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device 1379 * @dev: fallback device 1380 * 1381 * Return: 0 1382 **/ 1383 1384 static int 1385 ip6_fb_tnl_dev_init(struct net_device *dev) 1386 { 1387 struct ip6_tnl *t = netdev_priv(dev); 1388 struct net *net = dev_net(dev); 1389 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); 1390 1391 ip6_tnl_dev_init_gen(dev); 1392 t->parms.proto = IPPROTO_IPV6; 1393 dev_hold(dev); 1394 ip6n->tnls_wc[0] = t; 1395 return 0; 1396 } 1397 1398 static struct xfrm6_tunnel ip4ip6_handler = { 1399 .handler = ip4ip6_rcv, 1400 .err_handler = ip4ip6_err, 1401 .priority = 1, 1402 }; 1403 1404 static struct xfrm6_tunnel ip6ip6_handler = { 1405 .handler = ip6ip6_rcv, 1406 .err_handler = ip6ip6_err, 1407 .priority = 1, 1408 }; 1409 1410 static void ip6_tnl_destroy_tunnels(struct ip6_tnl_net *ip6n) 1411 { 1412 int h; 1413 struct ip6_tnl *t; 1414 1415 for (h = 0; h < HASH_SIZE; h++) { 1416 while ((t = ip6n->tnls_r_l[h]) != NULL) 1417 unregister_netdevice(t->dev); 1418 } 1419 1420 t = ip6n->tnls_wc[0]; 1421 unregister_netdevice(t->dev); 1422 } 1423 1424 static int ip6_tnl_init_net(struct net *net) 1425 { 1426 int err; 1427 struct ip6_tnl_net *ip6n; 1428 1429 err = -ENOMEM; 1430 ip6n = kzalloc(sizeof(struct ip6_tnl_net), GFP_KERNEL); 1431 if (ip6n == NULL) 1432 goto err_alloc; 1433 1434 err = net_assign_generic(net, ip6_tnl_net_id, ip6n); 1435 if (err < 0) 1436 goto err_assign; 1437 1438 ip6n->tnls[0] = ip6n->tnls_wc; 1439 ip6n->tnls[1] = ip6n->tnls_r_l; 1440 1441 err = -ENOMEM; 1442 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", 1443 ip6_tnl_dev_setup); 1444 1445 if (!ip6n->fb_tnl_dev) 1446 goto err_alloc_dev; 1447 1448 ip6n->fb_tnl_dev->init = ip6_fb_tnl_dev_init; 1449 dev_net_set(ip6n->fb_tnl_dev, net); 1450 1451 err = register_netdev(ip6n->fb_tnl_dev); 1452 if (err < 0) 1453 goto err_register; 1454 return 0; 1455 1456 err_register: 1457 free_netdev(ip6n->fb_tnl_dev); 1458 err_alloc_dev: 1459 /* nothing */ 1460 err_assign: 1461 kfree(ip6n); 1462 err_alloc: 1463 return err; 1464 } 1465 1466 static void ip6_tnl_exit_net(struct net *net) 1467 { 1468 struct ip6_tnl_net *ip6n; 1469 1470 ip6n = net_generic(net, ip6_tnl_net_id); 1471 rtnl_lock(); 1472 ip6_tnl_destroy_tunnels(ip6n); 1473 rtnl_unlock(); 1474 kfree(ip6n); 1475 } 1476 1477 static struct pernet_operations ip6_tnl_net_ops = { 1478 .init = ip6_tnl_init_net, 1479 .exit = ip6_tnl_exit_net, 1480 }; 1481 1482 /** 1483 * ip6_tunnel_init - register protocol and reserve needed resources 1484 * 1485 * Return: 0 on success 1486 **/ 1487 1488 static int __init ip6_tunnel_init(void) 1489 { 1490 int err; 1491 1492 if (xfrm6_tunnel_register(&ip4ip6_handler, AF_INET)) { 1493 printk(KERN_ERR "ip6_tunnel init: can't register ip4ip6\n"); 1494 err = -EAGAIN; 1495 goto out; 1496 } 1497 1498 if (xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6)) { 1499 printk(KERN_ERR "ip6_tunnel init: can't register ip6ip6\n"); 1500 err = -EAGAIN; 1501 goto unreg_ip4ip6; 1502 } 1503 1504 err = register_pernet_gen_device(&ip6_tnl_net_id, &ip6_tnl_net_ops); 1505 if (err < 0) 1506 goto err_pernet; 1507 return 0; 1508 err_pernet: 1509 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); 1510 unreg_ip4ip6: 1511 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); 1512 out: 1513 return err; 1514 } 1515 1516 /** 1517 * ip6_tunnel_cleanup - free resources and unregister protocol 1518 **/ 1519 1520 static void __exit ip6_tunnel_cleanup(void) 1521 { 1522 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) 1523 printk(KERN_INFO "ip6_tunnel close: can't deregister ip4ip6\n"); 1524 1525 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) 1526 printk(KERN_INFO "ip6_tunnel close: can't deregister ip6ip6\n"); 1527 1528 unregister_pernet_gen_device(ip6_tnl_net_id, &ip6_tnl_net_ops); 1529 } 1530 1531 module_init(ip6_tunnel_init); 1532 module_exit(ip6_tunnel_cleanup); 1533