1 /* 2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT) 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License 11 * as published by the Free Software Foundation; either version 12 * 2 of the License, or (at your option) any later version. 13 * 14 * Changes: 15 * Roger Venning <r.venning@telstra.com>: 6to4 support 16 * Nate Thompson <nate@thebog.net>: 6to4 support 17 * Fred Templin <fred.l.templin@boeing.com>: isatap support 18 */ 19 20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 21 22 #include <linux/module.h> 23 #include <linux/capability.h> 24 #include <linux/errno.h> 25 #include <linux/types.h> 26 #include <linux/socket.h> 27 #include <linux/sockios.h> 28 #include <linux/net.h> 29 #include <linux/in6.h> 30 #include <linux/netdevice.h> 31 #include <linux/if_arp.h> 32 #include <linux/icmp.h> 33 #include <linux/slab.h> 34 #include <asm/uaccess.h> 35 #include <linux/init.h> 36 #include <linux/netfilter_ipv4.h> 37 #include <linux/if_ether.h> 38 39 #include <net/sock.h> 40 #include <net/snmp.h> 41 42 #include <net/ipv6.h> 43 #include <net/protocol.h> 44 #include <net/transp_v6.h> 45 #include <net/ip6_fib.h> 46 #include <net/ip6_route.h> 47 #include <net/ndisc.h> 48 #include <net/addrconf.h> 49 #include <net/ip.h> 50 #include <net/udp.h> 51 #include <net/icmp.h> 52 #include <net/ip_tunnels.h> 53 #include <net/inet_ecn.h> 54 #include <net/xfrm.h> 55 #include <net/dsfield.h> 56 #include <net/net_namespace.h> 57 #include <net/netns/generic.h> 58 59 /* 60 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c 61 62 For comments look at net/ipv4/ip_gre.c --ANK 63 */ 64 65 #define HASH_SIZE 16 66 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF) 67 68 static bool log_ecn_error = true; 69 module_param(log_ecn_error, bool, 0644); 70 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 71 72 static int ipip6_tunnel_init(struct net_device *dev); 73 static void ipip6_tunnel_setup(struct net_device *dev); 74 static void ipip6_dev_free(struct net_device *dev); 75 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, 76 __be32 *v4dst); 77 static struct rtnl_link_ops sit_link_ops __read_mostly; 78 79 static int sit_net_id __read_mostly; 80 struct sit_net { 81 struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE]; 82 struct ip_tunnel __rcu *tunnels_r[HASH_SIZE]; 83 struct ip_tunnel __rcu *tunnels_l[HASH_SIZE]; 84 struct ip_tunnel __rcu *tunnels_wc[1]; 85 struct ip_tunnel __rcu **tunnels[4]; 86 87 struct net_device *fb_tunnel_dev; 88 }; 89 90 /* 91 * Must be invoked with rcu_read_lock 92 */ 93 static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net, 94 struct net_device *dev, __be32 remote, __be32 local) 95 { 96 unsigned int h0 = HASH(remote); 97 unsigned int h1 = HASH(local); 98 struct ip_tunnel *t; 99 struct sit_net *sitn = net_generic(net, sit_net_id); 100 101 for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) { 102 if (local == t->parms.iph.saddr && 103 remote == t->parms.iph.daddr && 104 (!dev || !t->parms.link || dev->iflink == t->parms.link) && 105 (t->dev->flags & IFF_UP)) 106 return t; 107 } 108 for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) { 109 if (remote == t->parms.iph.daddr && 110 (!dev || !t->parms.link || dev->iflink == t->parms.link) && 111 (t->dev->flags & IFF_UP)) 112 return t; 113 } 114 for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) { 115 if (local == t->parms.iph.saddr && 116 (!dev || !t->parms.link || dev->iflink == t->parms.link) && 117 (t->dev->flags & IFF_UP)) 118 return t; 119 } 120 t = rcu_dereference(sitn->tunnels_wc[0]); 121 if ((t != NULL) && (t->dev->flags & IFF_UP)) 122 return t; 123 return NULL; 124 } 125 126 static struct ip_tunnel __rcu **__ipip6_bucket(struct sit_net *sitn, 127 struct ip_tunnel_parm *parms) 128 { 129 __be32 remote = parms->iph.daddr; 130 __be32 local = parms->iph.saddr; 131 unsigned int h = 0; 132 int prio = 0; 133 134 if (remote) { 135 prio |= 2; 136 h ^= HASH(remote); 137 } 138 if (local) { 139 prio |= 1; 140 h ^= HASH(local); 141 } 142 return &sitn->tunnels[prio][h]; 143 } 144 145 static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn, 146 struct ip_tunnel *t) 147 { 148 return __ipip6_bucket(sitn, &t->parms); 149 } 150 151 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t) 152 { 153 struct ip_tunnel __rcu **tp; 154 struct ip_tunnel *iter; 155 156 for (tp = ipip6_bucket(sitn, t); 157 (iter = rtnl_dereference(*tp)) != NULL; 158 tp = &iter->next) { 159 if (t == iter) { 160 rcu_assign_pointer(*tp, t->next); 161 break; 162 } 163 } 164 } 165 166 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t) 167 { 168 struct ip_tunnel __rcu **tp = ipip6_bucket(sitn, t); 169 170 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 171 rcu_assign_pointer(*tp, t); 172 } 173 174 static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn) 175 { 176 #ifdef CONFIG_IPV6_SIT_6RD 177 struct ip_tunnel *t = netdev_priv(dev); 178 179 if (t->dev == sitn->fb_tunnel_dev) { 180 ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0); 181 t->ip6rd.relay_prefix = 0; 182 t->ip6rd.prefixlen = 16; 183 t->ip6rd.relay_prefixlen = 0; 184 } else { 185 struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev); 186 memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd)); 187 } 188 #endif 189 } 190 191 static int ipip6_tunnel_create(struct net_device *dev) 192 { 193 struct ip_tunnel *t = netdev_priv(dev); 194 struct net *net = dev_net(dev); 195 struct sit_net *sitn = net_generic(net, sit_net_id); 196 int err; 197 198 err = ipip6_tunnel_init(dev); 199 if (err < 0) 200 goto out; 201 ipip6_tunnel_clone_6rd(dev, sitn); 202 203 if ((__force u16)t->parms.i_flags & SIT_ISATAP) 204 dev->priv_flags |= IFF_ISATAP; 205 206 err = register_netdevice(dev); 207 if (err < 0) 208 goto out; 209 210 strcpy(t->parms.name, dev->name); 211 dev->rtnl_link_ops = &sit_link_ops; 212 213 dev_hold(dev); 214 215 ipip6_tunnel_link(sitn, t); 216 return 0; 217 218 out: 219 return err; 220 } 221 222 static struct ip_tunnel *ipip6_tunnel_locate(struct net *net, 223 struct ip_tunnel_parm *parms, int create) 224 { 225 __be32 remote = parms->iph.daddr; 226 __be32 local = parms->iph.saddr; 227 struct ip_tunnel *t, *nt; 228 struct ip_tunnel __rcu **tp; 229 struct net_device *dev; 230 char name[IFNAMSIZ]; 231 struct sit_net *sitn = net_generic(net, sit_net_id); 232 233 for (tp = __ipip6_bucket(sitn, parms); 234 (t = rtnl_dereference(*tp)) != NULL; 235 tp = &t->next) { 236 if (local == t->parms.iph.saddr && 237 remote == t->parms.iph.daddr && 238 parms->link == t->parms.link) { 239 if (create) 240 return NULL; 241 else 242 return t; 243 } 244 } 245 if (!create) 246 goto failed; 247 248 if (parms->name[0]) 249 strlcpy(name, parms->name, IFNAMSIZ); 250 else 251 strcpy(name, "sit%d"); 252 253 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup); 254 if (dev == NULL) 255 return NULL; 256 257 dev_net_set(dev, net); 258 259 nt = netdev_priv(dev); 260 261 nt->parms = *parms; 262 if (ipip6_tunnel_create(dev) < 0) 263 goto failed_free; 264 265 return nt; 266 267 failed_free: 268 ipip6_dev_free(dev); 269 failed: 270 return NULL; 271 } 272 273 #define for_each_prl_rcu(start) \ 274 for (prl = rcu_dereference(start); \ 275 prl; \ 276 prl = rcu_dereference(prl->next)) 277 278 static struct ip_tunnel_prl_entry * 279 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr) 280 { 281 struct ip_tunnel_prl_entry *prl; 282 283 for_each_prl_rcu(t->prl) 284 if (prl->addr == addr) 285 break; 286 return prl; 287 288 } 289 290 static int ipip6_tunnel_get_prl(struct ip_tunnel *t, 291 struct ip_tunnel_prl __user *a) 292 { 293 struct ip_tunnel_prl kprl, *kp; 294 struct ip_tunnel_prl_entry *prl; 295 unsigned int cmax, c = 0, ca, len; 296 int ret = 0; 297 298 if (copy_from_user(&kprl, a, sizeof(kprl))) 299 return -EFAULT; 300 cmax = kprl.datalen / sizeof(kprl); 301 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY)) 302 cmax = 1; 303 304 /* For simple GET or for root users, 305 * we try harder to allocate. 306 */ 307 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ? 308 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) : 309 NULL; 310 311 rcu_read_lock(); 312 313 ca = t->prl_count < cmax ? t->prl_count : cmax; 314 315 if (!kp) { 316 /* We don't try hard to allocate much memory for 317 * non-root users. 318 * For root users, retry allocating enough memory for 319 * the answer. 320 */ 321 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC); 322 if (!kp) { 323 ret = -ENOMEM; 324 goto out; 325 } 326 } 327 328 c = 0; 329 for_each_prl_rcu(t->prl) { 330 if (c >= cmax) 331 break; 332 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr) 333 continue; 334 kp[c].addr = prl->addr; 335 kp[c].flags = prl->flags; 336 c++; 337 if (kprl.addr != htonl(INADDR_ANY)) 338 break; 339 } 340 out: 341 rcu_read_unlock(); 342 343 len = sizeof(*kp) * c; 344 ret = 0; 345 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen)) 346 ret = -EFAULT; 347 348 kfree(kp); 349 350 return ret; 351 } 352 353 static int 354 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg) 355 { 356 struct ip_tunnel_prl_entry *p; 357 int err = 0; 358 359 if (a->addr == htonl(INADDR_ANY)) 360 return -EINVAL; 361 362 ASSERT_RTNL(); 363 364 for (p = rtnl_dereference(t->prl); p; p = rtnl_dereference(p->next)) { 365 if (p->addr == a->addr) { 366 if (chg) { 367 p->flags = a->flags; 368 goto out; 369 } 370 err = -EEXIST; 371 goto out; 372 } 373 } 374 375 if (chg) { 376 err = -ENXIO; 377 goto out; 378 } 379 380 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL); 381 if (!p) { 382 err = -ENOBUFS; 383 goto out; 384 } 385 386 p->next = t->prl; 387 p->addr = a->addr; 388 p->flags = a->flags; 389 t->prl_count++; 390 rcu_assign_pointer(t->prl, p); 391 out: 392 return err; 393 } 394 395 static void prl_list_destroy_rcu(struct rcu_head *head) 396 { 397 struct ip_tunnel_prl_entry *p, *n; 398 399 p = container_of(head, struct ip_tunnel_prl_entry, rcu_head); 400 do { 401 n = rcu_dereference_protected(p->next, 1); 402 kfree(p); 403 p = n; 404 } while (p); 405 } 406 407 static int 408 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a) 409 { 410 struct ip_tunnel_prl_entry *x; 411 struct ip_tunnel_prl_entry __rcu **p; 412 int err = 0; 413 414 ASSERT_RTNL(); 415 416 if (a && a->addr != htonl(INADDR_ANY)) { 417 for (p = &t->prl; 418 (x = rtnl_dereference(*p)) != NULL; 419 p = &x->next) { 420 if (x->addr == a->addr) { 421 *p = x->next; 422 kfree_rcu(x, rcu_head); 423 t->prl_count--; 424 goto out; 425 } 426 } 427 err = -ENXIO; 428 } else { 429 x = rtnl_dereference(t->prl); 430 if (x) { 431 t->prl_count = 0; 432 call_rcu(&x->rcu_head, prl_list_destroy_rcu); 433 t->prl = NULL; 434 } 435 } 436 out: 437 return err; 438 } 439 440 static int 441 isatap_chksrc(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *t) 442 { 443 struct ip_tunnel_prl_entry *p; 444 int ok = 1; 445 446 rcu_read_lock(); 447 p = __ipip6_tunnel_locate_prl(t, iph->saddr); 448 if (p) { 449 if (p->flags & PRL_DEFAULT) 450 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT; 451 else 452 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT; 453 } else { 454 const struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr; 455 456 if (ipv6_addr_is_isatap(addr6) && 457 (addr6->s6_addr32[3] == iph->saddr) && 458 ipv6_chk_prefix(addr6, t->dev)) 459 skb->ndisc_nodetype = NDISC_NODETYPE_HOST; 460 else 461 ok = 0; 462 } 463 rcu_read_unlock(); 464 return ok; 465 } 466 467 static void ipip6_tunnel_uninit(struct net_device *dev) 468 { 469 struct ip_tunnel *tunnel = netdev_priv(dev); 470 struct sit_net *sitn = net_generic(tunnel->net, sit_net_id); 471 472 if (dev == sitn->fb_tunnel_dev) { 473 RCU_INIT_POINTER(sitn->tunnels_wc[0], NULL); 474 } else { 475 ipip6_tunnel_unlink(sitn, tunnel); 476 ipip6_tunnel_del_prl(tunnel, NULL); 477 } 478 dev_put(dev); 479 } 480 481 482 static int ipip6_err(struct sk_buff *skb, u32 info) 483 { 484 485 /* All the routers (except for Linux) return only 486 8 bytes of packet payload. It means, that precise relaying of 487 ICMP in the real Internet is absolutely infeasible. 488 */ 489 const struct iphdr *iph = (const struct iphdr *)skb->data; 490 const int type = icmp_hdr(skb)->type; 491 const int code = icmp_hdr(skb)->code; 492 struct ip_tunnel *t; 493 int err; 494 495 switch (type) { 496 default: 497 case ICMP_PARAMETERPROB: 498 return 0; 499 500 case ICMP_DEST_UNREACH: 501 switch (code) { 502 case ICMP_SR_FAILED: 503 case ICMP_PORT_UNREACH: 504 /* Impossible event. */ 505 return 0; 506 default: 507 /* All others are translated to HOST_UNREACH. 508 rfc2003 contains "deep thoughts" about NET_UNREACH, 509 I believe they are just ether pollution. --ANK 510 */ 511 break; 512 } 513 break; 514 case ICMP_TIME_EXCEEDED: 515 if (code != ICMP_EXC_TTL) 516 return 0; 517 break; 518 case ICMP_REDIRECT: 519 break; 520 } 521 522 err = -ENOENT; 523 524 t = ipip6_tunnel_lookup(dev_net(skb->dev), 525 skb->dev, 526 iph->daddr, 527 iph->saddr); 528 if (t == NULL) 529 goto out; 530 531 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { 532 ipv4_update_pmtu(skb, dev_net(skb->dev), info, 533 t->dev->ifindex, 0, IPPROTO_IPV6, 0); 534 err = 0; 535 goto out; 536 } 537 if (type == ICMP_REDIRECT) { 538 ipv4_redirect(skb, dev_net(skb->dev), t->dev->ifindex, 0, 539 IPPROTO_IPV6, 0); 540 err = 0; 541 goto out; 542 } 543 544 if (t->parms.iph.daddr == 0) 545 goto out; 546 547 err = 0; 548 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) 549 goto out; 550 551 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) 552 t->err_count++; 553 else 554 t->err_count = 1; 555 t->err_time = jiffies; 556 out: 557 return err; 558 } 559 560 static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr, 561 const struct in6_addr *v6addr) 562 { 563 __be32 v4embed = 0; 564 if (check_6rd(tunnel, v6addr, &v4embed) && v4addr != v4embed) 565 return true; 566 return false; 567 } 568 569 static int ipip6_rcv(struct sk_buff *skb) 570 { 571 const struct iphdr *iph = ip_hdr(skb); 572 struct ip_tunnel *tunnel; 573 int err; 574 575 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev, 576 iph->saddr, iph->daddr); 577 if (tunnel != NULL) { 578 struct pcpu_tstats *tstats; 579 580 if (tunnel->parms.iph.protocol != IPPROTO_IPV6 && 581 tunnel->parms.iph.protocol != 0) 582 goto out; 583 584 skb->mac_header = skb->network_header; 585 skb_reset_network_header(skb); 586 IPCB(skb)->flags = 0; 587 skb->protocol = htons(ETH_P_IPV6); 588 589 if (tunnel->dev->priv_flags & IFF_ISATAP) { 590 if (!isatap_chksrc(skb, iph, tunnel)) { 591 tunnel->dev->stats.rx_errors++; 592 goto out; 593 } 594 } else if (!(tunnel->dev->flags&IFF_POINTOPOINT)) { 595 if (is_spoofed_6rd(tunnel, iph->saddr, 596 &ipv6_hdr(skb)->saddr) || 597 is_spoofed_6rd(tunnel, iph->daddr, 598 &ipv6_hdr(skb)->daddr)) { 599 tunnel->dev->stats.rx_errors++; 600 goto out; 601 } 602 } 603 604 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 605 606 err = IP_ECN_decapsulate(iph, skb); 607 if (unlikely(err)) { 608 if (log_ecn_error) 609 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", 610 &iph->saddr, iph->tos); 611 if (err > 1) { 612 ++tunnel->dev->stats.rx_frame_errors; 613 ++tunnel->dev->stats.rx_errors; 614 goto out; 615 } 616 } 617 618 tstats = this_cpu_ptr(tunnel->dev->tstats); 619 tstats->rx_packets++; 620 tstats->rx_bytes += skb->len; 621 622 netif_rx(skb); 623 624 return 0; 625 } 626 627 /* no tunnel matched, let upstream know, ipsec may handle it */ 628 return 1; 629 out: 630 kfree_skb(skb); 631 return 0; 632 } 633 634 static const struct tnl_ptk_info tpi = { 635 /* no tunnel info required for ipip. */ 636 .proto = htons(ETH_P_IP), 637 }; 638 639 static int ipip_rcv(struct sk_buff *skb) 640 { 641 const struct iphdr *iph; 642 struct ip_tunnel *tunnel; 643 644 iph = ip_hdr(skb); 645 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev, 646 iph->saddr, iph->daddr); 647 if (tunnel != NULL) { 648 if (tunnel->parms.iph.protocol != IPPROTO_IPIP && 649 tunnel->parms.iph.protocol != 0) 650 goto drop; 651 652 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) 653 goto drop; 654 if (iptunnel_pull_header(skb, 0, tpi.proto)) 655 goto drop; 656 return ip_tunnel_rcv(tunnel, skb, &tpi, log_ecn_error); 657 } 658 659 return 1; 660 661 drop: 662 kfree_skb(skb); 663 return 0; 664 } 665 666 /* 667 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function 668 * stores the embedded IPv4 address in v4dst and returns true. 669 */ 670 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, 671 __be32 *v4dst) 672 { 673 #ifdef CONFIG_IPV6_SIT_6RD 674 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix, 675 tunnel->ip6rd.prefixlen)) { 676 unsigned int pbw0, pbi0; 677 int pbi1; 678 u32 d; 679 680 pbw0 = tunnel->ip6rd.prefixlen >> 5; 681 pbi0 = tunnel->ip6rd.prefixlen & 0x1f; 682 683 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >> 684 tunnel->ip6rd.relay_prefixlen; 685 686 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen; 687 if (pbi1 > 0) 688 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >> 689 (32 - pbi1); 690 691 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d); 692 return true; 693 } 694 #else 695 if (v6dst->s6_addr16[0] == htons(0x2002)) { 696 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */ 697 memcpy(v4dst, &v6dst->s6_addr16[1], 4); 698 return true; 699 } 700 #endif 701 return false; 702 } 703 704 static inline __be32 try_6rd(struct ip_tunnel *tunnel, 705 const struct in6_addr *v6dst) 706 { 707 __be32 dst = 0; 708 check_6rd(tunnel, v6dst, &dst); 709 return dst; 710 } 711 712 /* 713 * This function assumes it is being called from dev_queue_xmit() 714 * and that skb is filled properly by that function. 715 */ 716 717 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, 718 struct net_device *dev) 719 { 720 struct ip_tunnel *tunnel = netdev_priv(dev); 721 const struct iphdr *tiph = &tunnel->parms.iph; 722 const struct ipv6hdr *iph6 = ipv6_hdr(skb); 723 u8 tos = tunnel->parms.iph.tos; 724 __be16 df = tiph->frag_off; 725 struct rtable *rt; /* Route to the other host */ 726 struct net_device *tdev; /* Device to other host */ 727 unsigned int max_headroom; /* The extra header space needed */ 728 __be32 dst = tiph->daddr; 729 struct flowi4 fl4; 730 int mtu; 731 const struct in6_addr *addr6; 732 int addr_type; 733 u8 ttl; 734 int err; 735 736 if (skb->protocol != htons(ETH_P_IPV6)) 737 goto tx_error; 738 739 if (tos == 1) 740 tos = ipv6_get_dsfield(iph6); 741 742 /* ISATAP (RFC4214) - must come before 6to4 */ 743 if (dev->priv_flags & IFF_ISATAP) { 744 struct neighbour *neigh = NULL; 745 bool do_tx_error = false; 746 747 if (skb_dst(skb)) 748 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr); 749 750 if (neigh == NULL) { 751 net_dbg_ratelimited("sit: nexthop == NULL\n"); 752 goto tx_error; 753 } 754 755 addr6 = (const struct in6_addr *)&neigh->primary_key; 756 addr_type = ipv6_addr_type(addr6); 757 758 if ((addr_type & IPV6_ADDR_UNICAST) && 759 ipv6_addr_is_isatap(addr6)) 760 dst = addr6->s6_addr32[3]; 761 else 762 do_tx_error = true; 763 764 neigh_release(neigh); 765 if (do_tx_error) 766 goto tx_error; 767 } 768 769 if (!dst) 770 dst = try_6rd(tunnel, &iph6->daddr); 771 772 if (!dst) { 773 struct neighbour *neigh = NULL; 774 bool do_tx_error = false; 775 776 if (skb_dst(skb)) 777 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr); 778 779 if (neigh == NULL) { 780 net_dbg_ratelimited("sit: nexthop == NULL\n"); 781 goto tx_error; 782 } 783 784 addr6 = (const struct in6_addr *)&neigh->primary_key; 785 addr_type = ipv6_addr_type(addr6); 786 787 if (addr_type == IPV6_ADDR_ANY) { 788 addr6 = &ipv6_hdr(skb)->daddr; 789 addr_type = ipv6_addr_type(addr6); 790 } 791 792 if ((addr_type & IPV6_ADDR_COMPATv4) != 0) 793 dst = addr6->s6_addr32[3]; 794 else 795 do_tx_error = true; 796 797 neigh_release(neigh); 798 if (do_tx_error) 799 goto tx_error; 800 } 801 802 rt = ip_route_output_ports(tunnel->net, &fl4, NULL, 803 dst, tiph->saddr, 804 0, 0, 805 IPPROTO_IPV6, RT_TOS(tos), 806 tunnel->parms.link); 807 if (IS_ERR(rt)) { 808 dev->stats.tx_carrier_errors++; 809 goto tx_error_icmp; 810 } 811 if (rt->rt_type != RTN_UNICAST) { 812 ip_rt_put(rt); 813 dev->stats.tx_carrier_errors++; 814 goto tx_error_icmp; 815 } 816 tdev = rt->dst.dev; 817 818 if (tdev == dev) { 819 ip_rt_put(rt); 820 dev->stats.collisions++; 821 goto tx_error; 822 } 823 824 if (df) { 825 mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr); 826 827 if (mtu < 68) { 828 dev->stats.collisions++; 829 ip_rt_put(rt); 830 goto tx_error; 831 } 832 833 if (mtu < IPV6_MIN_MTU) { 834 mtu = IPV6_MIN_MTU; 835 df = 0; 836 } 837 838 if (tunnel->parms.iph.daddr && skb_dst(skb)) 839 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 840 841 if (skb->len > mtu) { 842 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 843 ip_rt_put(rt); 844 goto tx_error; 845 } 846 } 847 848 if (tunnel->err_count > 0) { 849 if (time_before(jiffies, 850 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 851 tunnel->err_count--; 852 dst_link_failure(skb); 853 } else 854 tunnel->err_count = 0; 855 } 856 857 /* 858 * Okay, now see if we can stuff it in the buffer as-is. 859 */ 860 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr); 861 862 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 863 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 864 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); 865 if (!new_skb) { 866 ip_rt_put(rt); 867 dev->stats.tx_dropped++; 868 dev_kfree_skb(skb); 869 return NETDEV_TX_OK; 870 } 871 if (skb->sk) 872 skb_set_owner_w(new_skb, skb->sk); 873 dev_kfree_skb(skb); 874 skb = new_skb; 875 iph6 = ipv6_hdr(skb); 876 } 877 ttl = tiph->ttl; 878 if (ttl == 0) 879 ttl = iph6->hop_limit; 880 tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6)); 881 882 if (likely(!skb->encapsulation)) { 883 skb_reset_inner_headers(skb); 884 skb->encapsulation = 1; 885 } 886 887 err = iptunnel_xmit(rt, skb, fl4.saddr, fl4.daddr, IPPROTO_IPV6, tos, 888 ttl, df, !net_eq(tunnel->net, dev_net(dev))); 889 iptunnel_xmit_stats(err, &dev->stats, dev->tstats); 890 return NETDEV_TX_OK; 891 892 tx_error_icmp: 893 dst_link_failure(skb); 894 tx_error: 895 dev->stats.tx_errors++; 896 dev_kfree_skb(skb); 897 return NETDEV_TX_OK; 898 } 899 900 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) 901 { 902 struct ip_tunnel *tunnel = netdev_priv(dev); 903 const struct iphdr *tiph = &tunnel->parms.iph; 904 905 if (likely(!skb->encapsulation)) { 906 skb_reset_inner_headers(skb); 907 skb->encapsulation = 1; 908 } 909 910 ip_tunnel_xmit(skb, dev, tiph, IPPROTO_IPIP); 911 return NETDEV_TX_OK; 912 } 913 914 static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb, 915 struct net_device *dev) 916 { 917 switch (skb->protocol) { 918 case htons(ETH_P_IP): 919 ipip_tunnel_xmit(skb, dev); 920 break; 921 case htons(ETH_P_IPV6): 922 ipip6_tunnel_xmit(skb, dev); 923 break; 924 default: 925 goto tx_err; 926 } 927 928 return NETDEV_TX_OK; 929 930 tx_err: 931 dev->stats.tx_errors++; 932 dev_kfree_skb(skb); 933 return NETDEV_TX_OK; 934 935 } 936 937 static void ipip6_tunnel_bind_dev(struct net_device *dev) 938 { 939 struct net_device *tdev = NULL; 940 struct ip_tunnel *tunnel; 941 const struct iphdr *iph; 942 struct flowi4 fl4; 943 944 tunnel = netdev_priv(dev); 945 iph = &tunnel->parms.iph; 946 947 if (iph->daddr) { 948 struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4, 949 NULL, 950 iph->daddr, iph->saddr, 951 0, 0, 952 IPPROTO_IPV6, 953 RT_TOS(iph->tos), 954 tunnel->parms.link); 955 956 if (!IS_ERR(rt)) { 957 tdev = rt->dst.dev; 958 ip_rt_put(rt); 959 } 960 dev->flags |= IFF_POINTOPOINT; 961 } 962 963 if (!tdev && tunnel->parms.link) 964 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); 965 966 if (tdev) { 967 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); 968 dev->mtu = tdev->mtu - sizeof(struct iphdr); 969 if (dev->mtu < IPV6_MIN_MTU) 970 dev->mtu = IPV6_MIN_MTU; 971 } 972 dev->iflink = tunnel->parms.link; 973 } 974 975 static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p) 976 { 977 struct net *net = t->net; 978 struct sit_net *sitn = net_generic(net, sit_net_id); 979 980 ipip6_tunnel_unlink(sitn, t); 981 synchronize_net(); 982 t->parms.iph.saddr = p->iph.saddr; 983 t->parms.iph.daddr = p->iph.daddr; 984 memcpy(t->dev->dev_addr, &p->iph.saddr, 4); 985 memcpy(t->dev->broadcast, &p->iph.daddr, 4); 986 ipip6_tunnel_link(sitn, t); 987 t->parms.iph.ttl = p->iph.ttl; 988 t->parms.iph.tos = p->iph.tos; 989 if (t->parms.link != p->link) { 990 t->parms.link = p->link; 991 ipip6_tunnel_bind_dev(t->dev); 992 } 993 netdev_state_change(t->dev); 994 } 995 996 #ifdef CONFIG_IPV6_SIT_6RD 997 static int ipip6_tunnel_update_6rd(struct ip_tunnel *t, 998 struct ip_tunnel_6rd *ip6rd) 999 { 1000 struct in6_addr prefix; 1001 __be32 relay_prefix; 1002 1003 if (ip6rd->relay_prefixlen > 32 || 1004 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64) 1005 return -EINVAL; 1006 1007 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen); 1008 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix)) 1009 return -EINVAL; 1010 if (ip6rd->relay_prefixlen) 1011 relay_prefix = ip6rd->relay_prefix & 1012 htonl(0xffffffffUL << 1013 (32 - ip6rd->relay_prefixlen)); 1014 else 1015 relay_prefix = 0; 1016 if (relay_prefix != ip6rd->relay_prefix) 1017 return -EINVAL; 1018 1019 t->ip6rd.prefix = prefix; 1020 t->ip6rd.relay_prefix = relay_prefix; 1021 t->ip6rd.prefixlen = ip6rd->prefixlen; 1022 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen; 1023 netdev_state_change(t->dev); 1024 return 0; 1025 } 1026 #endif 1027 1028 static int 1029 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) 1030 { 1031 int err = 0; 1032 struct ip_tunnel_parm p; 1033 struct ip_tunnel_prl prl; 1034 struct ip_tunnel *t; 1035 struct net *net = dev_net(dev); 1036 struct sit_net *sitn = net_generic(net, sit_net_id); 1037 #ifdef CONFIG_IPV6_SIT_6RD 1038 struct ip_tunnel_6rd ip6rd; 1039 #endif 1040 1041 switch (cmd) { 1042 case SIOCGETTUNNEL: 1043 #ifdef CONFIG_IPV6_SIT_6RD 1044 case SIOCGET6RD: 1045 #endif 1046 t = NULL; 1047 if (dev == sitn->fb_tunnel_dev) { 1048 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1049 err = -EFAULT; 1050 break; 1051 } 1052 t = ipip6_tunnel_locate(net, &p, 0); 1053 } 1054 if (t == NULL) 1055 t = netdev_priv(dev); 1056 1057 err = -EFAULT; 1058 if (cmd == SIOCGETTUNNEL) { 1059 memcpy(&p, &t->parms, sizeof(p)); 1060 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, 1061 sizeof(p))) 1062 goto done; 1063 #ifdef CONFIG_IPV6_SIT_6RD 1064 } else { 1065 ip6rd.prefix = t->ip6rd.prefix; 1066 ip6rd.relay_prefix = t->ip6rd.relay_prefix; 1067 ip6rd.prefixlen = t->ip6rd.prefixlen; 1068 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen; 1069 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd, 1070 sizeof(ip6rd))) 1071 goto done; 1072 #endif 1073 } 1074 err = 0; 1075 break; 1076 1077 case SIOCADDTUNNEL: 1078 case SIOCCHGTUNNEL: 1079 err = -EPERM; 1080 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1081 goto done; 1082 1083 err = -EFAULT; 1084 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1085 goto done; 1086 1087 err = -EINVAL; 1088 if (p.iph.protocol != IPPROTO_IPV6 && 1089 p.iph.protocol != IPPROTO_IPIP && 1090 p.iph.protocol != 0) 1091 goto done; 1092 if (p.iph.version != 4 || 1093 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF))) 1094 goto done; 1095 if (p.iph.ttl) 1096 p.iph.frag_off |= htons(IP_DF); 1097 1098 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL); 1099 1100 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1101 if (t != NULL) { 1102 if (t->dev != dev) { 1103 err = -EEXIST; 1104 break; 1105 } 1106 } else { 1107 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) || 1108 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) { 1109 err = -EINVAL; 1110 break; 1111 } 1112 t = netdev_priv(dev); 1113 } 1114 1115 ipip6_tunnel_update(t, &p); 1116 } 1117 1118 if (t) { 1119 err = 0; 1120 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) 1121 err = -EFAULT; 1122 } else 1123 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1124 break; 1125 1126 case SIOCDELTUNNEL: 1127 err = -EPERM; 1128 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1129 goto done; 1130 1131 if (dev == sitn->fb_tunnel_dev) { 1132 err = -EFAULT; 1133 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1134 goto done; 1135 err = -ENOENT; 1136 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL) 1137 goto done; 1138 err = -EPERM; 1139 if (t == netdev_priv(sitn->fb_tunnel_dev)) 1140 goto done; 1141 dev = t->dev; 1142 } 1143 unregister_netdevice(dev); 1144 err = 0; 1145 break; 1146 1147 case SIOCGETPRL: 1148 err = -EINVAL; 1149 if (dev == sitn->fb_tunnel_dev) 1150 goto done; 1151 err = -ENOENT; 1152 if (!(t = netdev_priv(dev))) 1153 goto done; 1154 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data); 1155 break; 1156 1157 case SIOCADDPRL: 1158 case SIOCDELPRL: 1159 case SIOCCHGPRL: 1160 err = -EPERM; 1161 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1162 goto done; 1163 err = -EINVAL; 1164 if (dev == sitn->fb_tunnel_dev) 1165 goto done; 1166 err = -EFAULT; 1167 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl))) 1168 goto done; 1169 err = -ENOENT; 1170 if (!(t = netdev_priv(dev))) 1171 goto done; 1172 1173 switch (cmd) { 1174 case SIOCDELPRL: 1175 err = ipip6_tunnel_del_prl(t, &prl); 1176 break; 1177 case SIOCADDPRL: 1178 case SIOCCHGPRL: 1179 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL); 1180 break; 1181 } 1182 netdev_state_change(dev); 1183 break; 1184 1185 #ifdef CONFIG_IPV6_SIT_6RD 1186 case SIOCADD6RD: 1187 case SIOCCHG6RD: 1188 case SIOCDEL6RD: 1189 err = -EPERM; 1190 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1191 goto done; 1192 1193 err = -EFAULT; 1194 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data, 1195 sizeof(ip6rd))) 1196 goto done; 1197 1198 t = netdev_priv(dev); 1199 1200 if (cmd != SIOCDEL6RD) { 1201 err = ipip6_tunnel_update_6rd(t, &ip6rd); 1202 if (err < 0) 1203 goto done; 1204 } else 1205 ipip6_tunnel_clone_6rd(dev, sitn); 1206 1207 err = 0; 1208 break; 1209 #endif 1210 1211 default: 1212 err = -EINVAL; 1213 } 1214 1215 done: 1216 return err; 1217 } 1218 1219 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1220 { 1221 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr)) 1222 return -EINVAL; 1223 dev->mtu = new_mtu; 1224 return 0; 1225 } 1226 1227 static const struct net_device_ops ipip6_netdev_ops = { 1228 .ndo_uninit = ipip6_tunnel_uninit, 1229 .ndo_start_xmit = sit_tunnel_xmit, 1230 .ndo_do_ioctl = ipip6_tunnel_ioctl, 1231 .ndo_change_mtu = ipip6_tunnel_change_mtu, 1232 .ndo_get_stats64 = ip_tunnel_get_stats64, 1233 }; 1234 1235 static void ipip6_dev_free(struct net_device *dev) 1236 { 1237 free_percpu(dev->tstats); 1238 free_netdev(dev); 1239 } 1240 1241 static void ipip6_tunnel_setup(struct net_device *dev) 1242 { 1243 dev->netdev_ops = &ipip6_netdev_ops; 1244 dev->destructor = ipip6_dev_free; 1245 1246 dev->type = ARPHRD_SIT; 1247 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr); 1248 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr); 1249 dev->flags = IFF_NOARP; 1250 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1251 dev->iflink = 0; 1252 dev->addr_len = 4; 1253 dev->features |= NETIF_F_LLTX; 1254 } 1255 1256 static int ipip6_tunnel_init(struct net_device *dev) 1257 { 1258 struct ip_tunnel *tunnel = netdev_priv(dev); 1259 1260 tunnel->dev = dev; 1261 tunnel->net = dev_net(dev); 1262 1263 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); 1264 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); 1265 1266 ipip6_tunnel_bind_dev(dev); 1267 dev->tstats = alloc_percpu(struct pcpu_tstats); 1268 if (!dev->tstats) 1269 return -ENOMEM; 1270 1271 return 0; 1272 } 1273 1274 static int __net_init ipip6_fb_tunnel_init(struct net_device *dev) 1275 { 1276 struct ip_tunnel *tunnel = netdev_priv(dev); 1277 struct iphdr *iph = &tunnel->parms.iph; 1278 struct net *net = dev_net(dev); 1279 struct sit_net *sitn = net_generic(net, sit_net_id); 1280 1281 tunnel->dev = dev; 1282 tunnel->net = dev_net(dev); 1283 strcpy(tunnel->parms.name, dev->name); 1284 1285 iph->version = 4; 1286 iph->protocol = IPPROTO_IPV6; 1287 iph->ihl = 5; 1288 iph->ttl = 64; 1289 1290 dev->tstats = alloc_percpu(struct pcpu_tstats); 1291 if (!dev->tstats) 1292 return -ENOMEM; 1293 dev_hold(dev); 1294 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel); 1295 return 0; 1296 } 1297 1298 static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[]) 1299 { 1300 u8 proto; 1301 1302 if (!data || !data[IFLA_IPTUN_PROTO]) 1303 return 0; 1304 1305 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1306 if (proto != IPPROTO_IPV6 && 1307 proto != IPPROTO_IPIP && 1308 proto != 0) 1309 return -EINVAL; 1310 1311 return 0; 1312 } 1313 1314 static void ipip6_netlink_parms(struct nlattr *data[], 1315 struct ip_tunnel_parm *parms) 1316 { 1317 memset(parms, 0, sizeof(*parms)); 1318 1319 parms->iph.version = 4; 1320 parms->iph.protocol = IPPROTO_IPV6; 1321 parms->iph.ihl = 5; 1322 parms->iph.ttl = 64; 1323 1324 if (!data) 1325 return; 1326 1327 if (data[IFLA_IPTUN_LINK]) 1328 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1329 1330 if (data[IFLA_IPTUN_LOCAL]) 1331 parms->iph.saddr = nla_get_be32(data[IFLA_IPTUN_LOCAL]); 1332 1333 if (data[IFLA_IPTUN_REMOTE]) 1334 parms->iph.daddr = nla_get_be32(data[IFLA_IPTUN_REMOTE]); 1335 1336 if (data[IFLA_IPTUN_TTL]) { 1337 parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]); 1338 if (parms->iph.ttl) 1339 parms->iph.frag_off = htons(IP_DF); 1340 } 1341 1342 if (data[IFLA_IPTUN_TOS]) 1343 parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]); 1344 1345 if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC])) 1346 parms->iph.frag_off = htons(IP_DF); 1347 1348 if (data[IFLA_IPTUN_FLAGS]) 1349 parms->i_flags = nla_get_be16(data[IFLA_IPTUN_FLAGS]); 1350 1351 if (data[IFLA_IPTUN_PROTO]) 1352 parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1353 1354 } 1355 1356 #ifdef CONFIG_IPV6_SIT_6RD 1357 /* This function returns true when 6RD attributes are present in the nl msg */ 1358 static bool ipip6_netlink_6rd_parms(struct nlattr *data[], 1359 struct ip_tunnel_6rd *ip6rd) 1360 { 1361 bool ret = false; 1362 memset(ip6rd, 0, sizeof(*ip6rd)); 1363 1364 if (!data) 1365 return ret; 1366 1367 if (data[IFLA_IPTUN_6RD_PREFIX]) { 1368 ret = true; 1369 nla_memcpy(&ip6rd->prefix, data[IFLA_IPTUN_6RD_PREFIX], 1370 sizeof(struct in6_addr)); 1371 } 1372 1373 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) { 1374 ret = true; 1375 ip6rd->relay_prefix = 1376 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]); 1377 } 1378 1379 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) { 1380 ret = true; 1381 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]); 1382 } 1383 1384 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) { 1385 ret = true; 1386 ip6rd->relay_prefixlen = 1387 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]); 1388 } 1389 1390 return ret; 1391 } 1392 #endif 1393 1394 static int ipip6_newlink(struct net *src_net, struct net_device *dev, 1395 struct nlattr *tb[], struct nlattr *data[]) 1396 { 1397 struct net *net = dev_net(dev); 1398 struct ip_tunnel *nt; 1399 #ifdef CONFIG_IPV6_SIT_6RD 1400 struct ip_tunnel_6rd ip6rd; 1401 #endif 1402 int err; 1403 1404 nt = netdev_priv(dev); 1405 ipip6_netlink_parms(data, &nt->parms); 1406 1407 if (ipip6_tunnel_locate(net, &nt->parms, 0)) 1408 return -EEXIST; 1409 1410 err = ipip6_tunnel_create(dev); 1411 if (err < 0) 1412 return err; 1413 1414 #ifdef CONFIG_IPV6_SIT_6RD 1415 if (ipip6_netlink_6rd_parms(data, &ip6rd)) 1416 err = ipip6_tunnel_update_6rd(nt, &ip6rd); 1417 #endif 1418 1419 return err; 1420 } 1421 1422 static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[], 1423 struct nlattr *data[]) 1424 { 1425 struct ip_tunnel *t = netdev_priv(dev); 1426 struct ip_tunnel_parm p; 1427 struct net *net = t->net; 1428 struct sit_net *sitn = net_generic(net, sit_net_id); 1429 #ifdef CONFIG_IPV6_SIT_6RD 1430 struct ip_tunnel_6rd ip6rd; 1431 #endif 1432 1433 if (dev == sitn->fb_tunnel_dev) 1434 return -EINVAL; 1435 1436 ipip6_netlink_parms(data, &p); 1437 1438 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) || 1439 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr)) 1440 return -EINVAL; 1441 1442 t = ipip6_tunnel_locate(net, &p, 0); 1443 1444 if (t) { 1445 if (t->dev != dev) 1446 return -EEXIST; 1447 } else 1448 t = netdev_priv(dev); 1449 1450 ipip6_tunnel_update(t, &p); 1451 1452 #ifdef CONFIG_IPV6_SIT_6RD 1453 if (ipip6_netlink_6rd_parms(data, &ip6rd)) 1454 return ipip6_tunnel_update_6rd(t, &ip6rd); 1455 #endif 1456 1457 return 0; 1458 } 1459 1460 static size_t ipip6_get_size(const struct net_device *dev) 1461 { 1462 return 1463 /* IFLA_IPTUN_LINK */ 1464 nla_total_size(4) + 1465 /* IFLA_IPTUN_LOCAL */ 1466 nla_total_size(4) + 1467 /* IFLA_IPTUN_REMOTE */ 1468 nla_total_size(4) + 1469 /* IFLA_IPTUN_TTL */ 1470 nla_total_size(1) + 1471 /* IFLA_IPTUN_TOS */ 1472 nla_total_size(1) + 1473 /* IFLA_IPTUN_PMTUDISC */ 1474 nla_total_size(1) + 1475 /* IFLA_IPTUN_FLAGS */ 1476 nla_total_size(2) + 1477 /* IFLA_IPTUN_PROTO */ 1478 nla_total_size(1) + 1479 #ifdef CONFIG_IPV6_SIT_6RD 1480 /* IFLA_IPTUN_6RD_PREFIX */ 1481 nla_total_size(sizeof(struct in6_addr)) + 1482 /* IFLA_IPTUN_6RD_RELAY_PREFIX */ 1483 nla_total_size(4) + 1484 /* IFLA_IPTUN_6RD_PREFIXLEN */ 1485 nla_total_size(2) + 1486 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */ 1487 nla_total_size(2) + 1488 #endif 1489 0; 1490 } 1491 1492 static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev) 1493 { 1494 struct ip_tunnel *tunnel = netdev_priv(dev); 1495 struct ip_tunnel_parm *parm = &tunnel->parms; 1496 1497 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 1498 nla_put_be32(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) || 1499 nla_put_be32(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) || 1500 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) || 1501 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) || 1502 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC, 1503 !!(parm->iph.frag_off & htons(IP_DF))) || 1504 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) || 1505 nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags)) 1506 goto nla_put_failure; 1507 1508 #ifdef CONFIG_IPV6_SIT_6RD 1509 if (nla_put(skb, IFLA_IPTUN_6RD_PREFIX, sizeof(struct in6_addr), 1510 &tunnel->ip6rd.prefix) || 1511 nla_put_be32(skb, IFLA_IPTUN_6RD_RELAY_PREFIX, 1512 tunnel->ip6rd.relay_prefix) || 1513 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN, 1514 tunnel->ip6rd.prefixlen) || 1515 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN, 1516 tunnel->ip6rd.relay_prefixlen)) 1517 goto nla_put_failure; 1518 #endif 1519 1520 return 0; 1521 1522 nla_put_failure: 1523 return -EMSGSIZE; 1524 } 1525 1526 static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = { 1527 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 1528 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 }, 1529 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 }, 1530 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 1531 [IFLA_IPTUN_TOS] = { .type = NLA_U8 }, 1532 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 }, 1533 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 }, 1534 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 1535 #ifdef CONFIG_IPV6_SIT_6RD 1536 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) }, 1537 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 }, 1538 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 }, 1539 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 }, 1540 #endif 1541 }; 1542 1543 static struct rtnl_link_ops sit_link_ops __read_mostly = { 1544 .kind = "sit", 1545 .maxtype = IFLA_IPTUN_MAX, 1546 .policy = ipip6_policy, 1547 .priv_size = sizeof(struct ip_tunnel), 1548 .setup = ipip6_tunnel_setup, 1549 .validate = ipip6_validate, 1550 .newlink = ipip6_newlink, 1551 .changelink = ipip6_changelink, 1552 .get_size = ipip6_get_size, 1553 .fill_info = ipip6_fill_info, 1554 }; 1555 1556 static struct xfrm_tunnel sit_handler __read_mostly = { 1557 .handler = ipip6_rcv, 1558 .err_handler = ipip6_err, 1559 .priority = 1, 1560 }; 1561 1562 static struct xfrm_tunnel ipip_handler __read_mostly = { 1563 .handler = ipip_rcv, 1564 .err_handler = ipip6_err, 1565 .priority = 2, 1566 }; 1567 1568 static void __net_exit sit_destroy_tunnels(struct sit_net *sitn, struct list_head *head) 1569 { 1570 struct net *net = dev_net(sitn->fb_tunnel_dev); 1571 struct net_device *dev, *aux; 1572 int prio; 1573 1574 for_each_netdev_safe(net, dev, aux) 1575 if (dev->rtnl_link_ops == &sit_link_ops) 1576 unregister_netdevice_queue(dev, head); 1577 1578 for (prio = 1; prio < 4; prio++) { 1579 int h; 1580 for (h = 0; h < HASH_SIZE; h++) { 1581 struct ip_tunnel *t; 1582 1583 t = rtnl_dereference(sitn->tunnels[prio][h]); 1584 while (t != NULL) { 1585 /* If dev is in the same netns, it has already 1586 * been added to the list by the previous loop. 1587 */ 1588 if (!net_eq(dev_net(t->dev), net)) 1589 unregister_netdevice_queue(t->dev, 1590 head); 1591 t = rtnl_dereference(t->next); 1592 } 1593 } 1594 } 1595 } 1596 1597 static int __net_init sit_init_net(struct net *net) 1598 { 1599 struct sit_net *sitn = net_generic(net, sit_net_id); 1600 struct ip_tunnel *t; 1601 int err; 1602 1603 sitn->tunnels[0] = sitn->tunnels_wc; 1604 sitn->tunnels[1] = sitn->tunnels_l; 1605 sitn->tunnels[2] = sitn->tunnels_r; 1606 sitn->tunnels[3] = sitn->tunnels_r_l; 1607 1608 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0", 1609 ipip6_tunnel_setup); 1610 if (!sitn->fb_tunnel_dev) { 1611 err = -ENOMEM; 1612 goto err_alloc_dev; 1613 } 1614 dev_net_set(sitn->fb_tunnel_dev, net); 1615 /* FB netdevice is special: we have one, and only one per netns. 1616 * Allowing to move it to another netns is clearly unsafe. 1617 */ 1618 sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1619 1620 err = ipip6_fb_tunnel_init(sitn->fb_tunnel_dev); 1621 if (err) 1622 goto err_dev_free; 1623 1624 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn); 1625 1626 if ((err = register_netdev(sitn->fb_tunnel_dev))) 1627 goto err_reg_dev; 1628 1629 t = netdev_priv(sitn->fb_tunnel_dev); 1630 1631 strcpy(t->parms.name, sitn->fb_tunnel_dev->name); 1632 return 0; 1633 1634 err_reg_dev: 1635 dev_put(sitn->fb_tunnel_dev); 1636 err_dev_free: 1637 ipip6_dev_free(sitn->fb_tunnel_dev); 1638 err_alloc_dev: 1639 return err; 1640 } 1641 1642 static void __net_exit sit_exit_net(struct net *net) 1643 { 1644 struct sit_net *sitn = net_generic(net, sit_net_id); 1645 LIST_HEAD(list); 1646 1647 rtnl_lock(); 1648 sit_destroy_tunnels(sitn, &list); 1649 unregister_netdevice_queue(sitn->fb_tunnel_dev, &list); 1650 unregister_netdevice_many(&list); 1651 rtnl_unlock(); 1652 } 1653 1654 static struct pernet_operations sit_net_ops = { 1655 .init = sit_init_net, 1656 .exit = sit_exit_net, 1657 .id = &sit_net_id, 1658 .size = sizeof(struct sit_net), 1659 }; 1660 1661 static void __exit sit_cleanup(void) 1662 { 1663 rtnl_link_unregister(&sit_link_ops); 1664 xfrm4_tunnel_deregister(&sit_handler, AF_INET6); 1665 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 1666 1667 unregister_pernet_device(&sit_net_ops); 1668 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1669 } 1670 1671 static int __init sit_init(void) 1672 { 1673 int err; 1674 1675 pr_info("IPv6 over IPv4 tunneling driver\n"); 1676 1677 err = register_pernet_device(&sit_net_ops); 1678 if (err < 0) 1679 return err; 1680 err = xfrm4_tunnel_register(&sit_handler, AF_INET6); 1681 if (err < 0) { 1682 pr_info("%s: can't register ip6ip4\n", __func__); 1683 goto xfrm_tunnel_failed; 1684 } 1685 err = xfrm4_tunnel_register(&ipip_handler, AF_INET); 1686 if (err < 0) { 1687 pr_info("%s: can't register ip4ip4\n", __func__); 1688 goto xfrm_tunnel4_failed; 1689 } 1690 err = rtnl_link_register(&sit_link_ops); 1691 if (err < 0) 1692 goto rtnl_link_failed; 1693 1694 out: 1695 return err; 1696 1697 rtnl_link_failed: 1698 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 1699 xfrm_tunnel4_failed: 1700 xfrm4_tunnel_deregister(&sit_handler, AF_INET6); 1701 xfrm_tunnel_failed: 1702 unregister_pernet_device(&sit_net_ops); 1703 goto out; 1704 } 1705 1706 module_init(sit_init); 1707 module_exit(sit_cleanup); 1708 MODULE_LICENSE("GPL"); 1709 MODULE_ALIAS_NETDEV("sit0"); 1710