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 secpath_reset(skb); 585 skb->mac_header = skb->network_header; 586 skb_reset_network_header(skb); 587 IPCB(skb)->flags = 0; 588 skb->protocol = htons(ETH_P_IPV6); 589 skb->pkt_type = PACKET_HOST; 590 591 if (tunnel->dev->priv_flags & IFF_ISATAP) { 592 if (!isatap_chksrc(skb, iph, tunnel)) { 593 tunnel->dev->stats.rx_errors++; 594 goto out; 595 } 596 } else if (!(tunnel->dev->flags&IFF_POINTOPOINT)) { 597 if (is_spoofed_6rd(tunnel, iph->saddr, 598 &ipv6_hdr(skb)->saddr) || 599 is_spoofed_6rd(tunnel, iph->daddr, 600 &ipv6_hdr(skb)->daddr)) { 601 tunnel->dev->stats.rx_errors++; 602 goto out; 603 } 604 } 605 606 __skb_tunnel_rx(skb, tunnel->dev); 607 608 err = IP_ECN_decapsulate(iph, skb); 609 if (unlikely(err)) { 610 if (log_ecn_error) 611 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", 612 &iph->saddr, iph->tos); 613 if (err > 1) { 614 ++tunnel->dev->stats.rx_frame_errors; 615 ++tunnel->dev->stats.rx_errors; 616 goto out; 617 } 618 } 619 620 tstats = this_cpu_ptr(tunnel->dev->tstats); 621 tstats->rx_packets++; 622 tstats->rx_bytes += skb->len; 623 624 if (tunnel->net != dev_net(tunnel->dev)) 625 skb_scrub_packet(skb); 626 netif_rx(skb); 627 628 return 0; 629 } 630 631 /* no tunnel matched, let upstream know, ipsec may handle it */ 632 return 1; 633 out: 634 kfree_skb(skb); 635 return 0; 636 } 637 638 static const struct tnl_ptk_info tpi = { 639 /* no tunnel info required for ipip. */ 640 .proto = htons(ETH_P_IP), 641 }; 642 643 static int ipip_rcv(struct sk_buff *skb) 644 { 645 const struct iphdr *iph; 646 struct ip_tunnel *tunnel; 647 648 if (iptunnel_pull_header(skb, 0, tpi.proto)) 649 goto drop; 650 651 iph = ip_hdr(skb); 652 653 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev, 654 iph->saddr, iph->daddr); 655 if (tunnel != NULL) { 656 if (tunnel->parms.iph.protocol != IPPROTO_IPIP && 657 tunnel->parms.iph.protocol != 0) 658 goto drop; 659 660 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) 661 goto drop; 662 return ip_tunnel_rcv(tunnel, skb, &tpi, log_ecn_error); 663 } 664 665 return 1; 666 667 drop: 668 kfree_skb(skb); 669 return 0; 670 } 671 672 /* 673 * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function 674 * stores the embedded IPv4 address in v4dst and returns true. 675 */ 676 static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, 677 __be32 *v4dst) 678 { 679 #ifdef CONFIG_IPV6_SIT_6RD 680 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix, 681 tunnel->ip6rd.prefixlen)) { 682 unsigned int pbw0, pbi0; 683 int pbi1; 684 u32 d; 685 686 pbw0 = tunnel->ip6rd.prefixlen >> 5; 687 pbi0 = tunnel->ip6rd.prefixlen & 0x1f; 688 689 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >> 690 tunnel->ip6rd.relay_prefixlen; 691 692 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen; 693 if (pbi1 > 0) 694 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >> 695 (32 - pbi1); 696 697 *v4dst = tunnel->ip6rd.relay_prefix | htonl(d); 698 return true; 699 } 700 #else 701 if (v6dst->s6_addr16[0] == htons(0x2002)) { 702 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */ 703 memcpy(v4dst, &v6dst->s6_addr16[1], 4); 704 return true; 705 } 706 #endif 707 return false; 708 } 709 710 static inline __be32 try_6rd(struct ip_tunnel *tunnel, 711 const struct in6_addr *v6dst) 712 { 713 __be32 dst = 0; 714 check_6rd(tunnel, v6dst, &dst); 715 return dst; 716 } 717 718 /* 719 * This function assumes it is being called from dev_queue_xmit() 720 * and that skb is filled properly by that function. 721 */ 722 723 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, 724 struct net_device *dev) 725 { 726 struct ip_tunnel *tunnel = netdev_priv(dev); 727 const struct iphdr *tiph = &tunnel->parms.iph; 728 const struct ipv6hdr *iph6 = ipv6_hdr(skb); 729 u8 tos = tunnel->parms.iph.tos; 730 __be16 df = tiph->frag_off; 731 struct rtable *rt; /* Route to the other host */ 732 struct net_device *tdev; /* Device to other host */ 733 unsigned int max_headroom; /* The extra header space needed */ 734 __be32 dst = tiph->daddr; 735 struct flowi4 fl4; 736 int mtu; 737 const struct in6_addr *addr6; 738 int addr_type; 739 u8 ttl; 740 int err; 741 742 if (skb->protocol != htons(ETH_P_IPV6)) 743 goto tx_error; 744 745 if (tos == 1) 746 tos = ipv6_get_dsfield(iph6); 747 748 /* ISATAP (RFC4214) - must come before 6to4 */ 749 if (dev->priv_flags & IFF_ISATAP) { 750 struct neighbour *neigh = NULL; 751 bool do_tx_error = false; 752 753 if (skb_dst(skb)) 754 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr); 755 756 if (neigh == NULL) { 757 net_dbg_ratelimited("sit: nexthop == NULL\n"); 758 goto tx_error; 759 } 760 761 addr6 = (const struct in6_addr *)&neigh->primary_key; 762 addr_type = ipv6_addr_type(addr6); 763 764 if ((addr_type & IPV6_ADDR_UNICAST) && 765 ipv6_addr_is_isatap(addr6)) 766 dst = addr6->s6_addr32[3]; 767 else 768 do_tx_error = true; 769 770 neigh_release(neigh); 771 if (do_tx_error) 772 goto tx_error; 773 } 774 775 if (!dst) 776 dst = try_6rd(tunnel, &iph6->daddr); 777 778 if (!dst) { 779 struct neighbour *neigh = NULL; 780 bool do_tx_error = false; 781 782 if (skb_dst(skb)) 783 neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr); 784 785 if (neigh == NULL) { 786 net_dbg_ratelimited("sit: nexthop == NULL\n"); 787 goto tx_error; 788 } 789 790 addr6 = (const struct in6_addr *)&neigh->primary_key; 791 addr_type = ipv6_addr_type(addr6); 792 793 if (addr_type == IPV6_ADDR_ANY) { 794 addr6 = &ipv6_hdr(skb)->daddr; 795 addr_type = ipv6_addr_type(addr6); 796 } 797 798 if ((addr_type & IPV6_ADDR_COMPATv4) != 0) 799 dst = addr6->s6_addr32[3]; 800 else 801 do_tx_error = true; 802 803 neigh_release(neigh); 804 if (do_tx_error) 805 goto tx_error; 806 } 807 808 rt = ip_route_output_ports(tunnel->net, &fl4, NULL, 809 dst, tiph->saddr, 810 0, 0, 811 IPPROTO_IPV6, RT_TOS(tos), 812 tunnel->parms.link); 813 if (IS_ERR(rt)) { 814 dev->stats.tx_carrier_errors++; 815 goto tx_error_icmp; 816 } 817 if (rt->rt_type != RTN_UNICAST) { 818 ip_rt_put(rt); 819 dev->stats.tx_carrier_errors++; 820 goto tx_error_icmp; 821 } 822 tdev = rt->dst.dev; 823 824 if (tdev == dev) { 825 ip_rt_put(rt); 826 dev->stats.collisions++; 827 goto tx_error; 828 } 829 830 if (df) { 831 mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr); 832 833 if (mtu < 68) { 834 dev->stats.collisions++; 835 ip_rt_put(rt); 836 goto tx_error; 837 } 838 839 if (mtu < IPV6_MIN_MTU) { 840 mtu = IPV6_MIN_MTU; 841 df = 0; 842 } 843 844 if (tunnel->parms.iph.daddr && skb_dst(skb)) 845 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 846 847 if (skb->len > mtu) { 848 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 849 ip_rt_put(rt); 850 goto tx_error; 851 } 852 } 853 854 if (tunnel->err_count > 0) { 855 if (time_before(jiffies, 856 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 857 tunnel->err_count--; 858 dst_link_failure(skb); 859 } else 860 tunnel->err_count = 0; 861 } 862 863 if (tunnel->net != dev_net(dev)) 864 skb_scrub_packet(skb); 865 866 /* 867 * Okay, now see if we can stuff it in the buffer as-is. 868 */ 869 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr); 870 871 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 872 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 873 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); 874 if (!new_skb) { 875 ip_rt_put(rt); 876 dev->stats.tx_dropped++; 877 dev_kfree_skb(skb); 878 return NETDEV_TX_OK; 879 } 880 if (skb->sk) 881 skb_set_owner_w(new_skb, skb->sk); 882 dev_kfree_skb(skb); 883 skb = new_skb; 884 iph6 = ipv6_hdr(skb); 885 } 886 ttl = tiph->ttl; 887 if (ttl == 0) 888 ttl = iph6->hop_limit; 889 tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6)); 890 891 err = iptunnel_xmit(dev_net(dev), rt, skb, fl4.saddr, fl4.daddr, 892 IPPROTO_IPV6, tos, ttl, df); 893 iptunnel_xmit_stats(err, &dev->stats, dev->tstats); 894 return NETDEV_TX_OK; 895 896 tx_error_icmp: 897 dst_link_failure(skb); 898 tx_error: 899 dev->stats.tx_errors++; 900 dev_kfree_skb(skb); 901 return NETDEV_TX_OK; 902 } 903 904 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) 905 { 906 struct ip_tunnel *tunnel = netdev_priv(dev); 907 const struct iphdr *tiph = &tunnel->parms.iph; 908 909 if (likely(!skb->encapsulation)) { 910 skb_reset_inner_headers(skb); 911 skb->encapsulation = 1; 912 } 913 914 ip_tunnel_xmit(skb, dev, tiph, IPPROTO_IPIP); 915 return NETDEV_TX_OK; 916 } 917 918 static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb, 919 struct net_device *dev) 920 { 921 switch (skb->protocol) { 922 case htons(ETH_P_IP): 923 ipip_tunnel_xmit(skb, dev); 924 break; 925 case htons(ETH_P_IPV6): 926 ipip6_tunnel_xmit(skb, dev); 927 break; 928 default: 929 goto tx_err; 930 } 931 932 return NETDEV_TX_OK; 933 934 tx_err: 935 dev->stats.tx_errors++; 936 dev_kfree_skb(skb); 937 return NETDEV_TX_OK; 938 939 } 940 941 static void ipip6_tunnel_bind_dev(struct net_device *dev) 942 { 943 struct net_device *tdev = NULL; 944 struct ip_tunnel *tunnel; 945 const struct iphdr *iph; 946 struct flowi4 fl4; 947 948 tunnel = netdev_priv(dev); 949 iph = &tunnel->parms.iph; 950 951 if (iph->daddr) { 952 struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4, 953 NULL, 954 iph->daddr, iph->saddr, 955 0, 0, 956 IPPROTO_IPV6, 957 RT_TOS(iph->tos), 958 tunnel->parms.link); 959 960 if (!IS_ERR(rt)) { 961 tdev = rt->dst.dev; 962 ip_rt_put(rt); 963 } 964 dev->flags |= IFF_POINTOPOINT; 965 } 966 967 if (!tdev && tunnel->parms.link) 968 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); 969 970 if (tdev) { 971 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); 972 dev->mtu = tdev->mtu - sizeof(struct iphdr); 973 if (dev->mtu < IPV6_MIN_MTU) 974 dev->mtu = IPV6_MIN_MTU; 975 } 976 dev->iflink = tunnel->parms.link; 977 } 978 979 static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p) 980 { 981 struct net *net = t->net; 982 struct sit_net *sitn = net_generic(net, sit_net_id); 983 984 ipip6_tunnel_unlink(sitn, t); 985 synchronize_net(); 986 t->parms.iph.saddr = p->iph.saddr; 987 t->parms.iph.daddr = p->iph.daddr; 988 memcpy(t->dev->dev_addr, &p->iph.saddr, 4); 989 memcpy(t->dev->broadcast, &p->iph.daddr, 4); 990 ipip6_tunnel_link(sitn, t); 991 t->parms.iph.ttl = p->iph.ttl; 992 t->parms.iph.tos = p->iph.tos; 993 if (t->parms.link != p->link) { 994 t->parms.link = p->link; 995 ipip6_tunnel_bind_dev(t->dev); 996 } 997 netdev_state_change(t->dev); 998 } 999 1000 #ifdef CONFIG_IPV6_SIT_6RD 1001 static int ipip6_tunnel_update_6rd(struct ip_tunnel *t, 1002 struct ip_tunnel_6rd *ip6rd) 1003 { 1004 struct in6_addr prefix; 1005 __be32 relay_prefix; 1006 1007 if (ip6rd->relay_prefixlen > 32 || 1008 ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64) 1009 return -EINVAL; 1010 1011 ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen); 1012 if (!ipv6_addr_equal(&prefix, &ip6rd->prefix)) 1013 return -EINVAL; 1014 if (ip6rd->relay_prefixlen) 1015 relay_prefix = ip6rd->relay_prefix & 1016 htonl(0xffffffffUL << 1017 (32 - ip6rd->relay_prefixlen)); 1018 else 1019 relay_prefix = 0; 1020 if (relay_prefix != ip6rd->relay_prefix) 1021 return -EINVAL; 1022 1023 t->ip6rd.prefix = prefix; 1024 t->ip6rd.relay_prefix = relay_prefix; 1025 t->ip6rd.prefixlen = ip6rd->prefixlen; 1026 t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen; 1027 netdev_state_change(t->dev); 1028 return 0; 1029 } 1030 #endif 1031 1032 static int 1033 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) 1034 { 1035 int err = 0; 1036 struct ip_tunnel_parm p; 1037 struct ip_tunnel_prl prl; 1038 struct ip_tunnel *t; 1039 struct net *net = dev_net(dev); 1040 struct sit_net *sitn = net_generic(net, sit_net_id); 1041 #ifdef CONFIG_IPV6_SIT_6RD 1042 struct ip_tunnel_6rd ip6rd; 1043 #endif 1044 1045 switch (cmd) { 1046 case SIOCGETTUNNEL: 1047 #ifdef CONFIG_IPV6_SIT_6RD 1048 case SIOCGET6RD: 1049 #endif 1050 t = NULL; 1051 if (dev == sitn->fb_tunnel_dev) { 1052 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1053 err = -EFAULT; 1054 break; 1055 } 1056 t = ipip6_tunnel_locate(net, &p, 0); 1057 } 1058 if (t == NULL) 1059 t = netdev_priv(dev); 1060 1061 err = -EFAULT; 1062 if (cmd == SIOCGETTUNNEL) { 1063 memcpy(&p, &t->parms, sizeof(p)); 1064 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, 1065 sizeof(p))) 1066 goto done; 1067 #ifdef CONFIG_IPV6_SIT_6RD 1068 } else { 1069 ip6rd.prefix = t->ip6rd.prefix; 1070 ip6rd.relay_prefix = t->ip6rd.relay_prefix; 1071 ip6rd.prefixlen = t->ip6rd.prefixlen; 1072 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen; 1073 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd, 1074 sizeof(ip6rd))) 1075 goto done; 1076 #endif 1077 } 1078 err = 0; 1079 break; 1080 1081 case SIOCADDTUNNEL: 1082 case SIOCCHGTUNNEL: 1083 err = -EPERM; 1084 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1085 goto done; 1086 1087 err = -EFAULT; 1088 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1089 goto done; 1090 1091 err = -EINVAL; 1092 if (p.iph.protocol != IPPROTO_IPV6 && 1093 p.iph.protocol != IPPROTO_IPIP && 1094 p.iph.protocol != 0) 1095 goto done; 1096 if (p.iph.version != 4 || 1097 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF))) 1098 goto done; 1099 if (p.iph.ttl) 1100 p.iph.frag_off |= htons(IP_DF); 1101 1102 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL); 1103 1104 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1105 if (t != NULL) { 1106 if (t->dev != dev) { 1107 err = -EEXIST; 1108 break; 1109 } 1110 } else { 1111 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) || 1112 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) { 1113 err = -EINVAL; 1114 break; 1115 } 1116 t = netdev_priv(dev); 1117 } 1118 1119 ipip6_tunnel_update(t, &p); 1120 } 1121 1122 if (t) { 1123 err = 0; 1124 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) 1125 err = -EFAULT; 1126 } else 1127 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1128 break; 1129 1130 case SIOCDELTUNNEL: 1131 err = -EPERM; 1132 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1133 goto done; 1134 1135 if (dev == sitn->fb_tunnel_dev) { 1136 err = -EFAULT; 1137 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1138 goto done; 1139 err = -ENOENT; 1140 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL) 1141 goto done; 1142 err = -EPERM; 1143 if (t == netdev_priv(sitn->fb_tunnel_dev)) 1144 goto done; 1145 dev = t->dev; 1146 } 1147 unregister_netdevice(dev); 1148 err = 0; 1149 break; 1150 1151 case SIOCGETPRL: 1152 err = -EINVAL; 1153 if (dev == sitn->fb_tunnel_dev) 1154 goto done; 1155 err = -ENOENT; 1156 if (!(t = netdev_priv(dev))) 1157 goto done; 1158 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data); 1159 break; 1160 1161 case SIOCADDPRL: 1162 case SIOCDELPRL: 1163 case SIOCCHGPRL: 1164 err = -EPERM; 1165 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1166 goto done; 1167 err = -EINVAL; 1168 if (dev == sitn->fb_tunnel_dev) 1169 goto done; 1170 err = -EFAULT; 1171 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl))) 1172 goto done; 1173 err = -ENOENT; 1174 if (!(t = netdev_priv(dev))) 1175 goto done; 1176 1177 switch (cmd) { 1178 case SIOCDELPRL: 1179 err = ipip6_tunnel_del_prl(t, &prl); 1180 break; 1181 case SIOCADDPRL: 1182 case SIOCCHGPRL: 1183 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL); 1184 break; 1185 } 1186 netdev_state_change(dev); 1187 break; 1188 1189 #ifdef CONFIG_IPV6_SIT_6RD 1190 case SIOCADD6RD: 1191 case SIOCCHG6RD: 1192 case SIOCDEL6RD: 1193 err = -EPERM; 1194 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1195 goto done; 1196 1197 err = -EFAULT; 1198 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data, 1199 sizeof(ip6rd))) 1200 goto done; 1201 1202 t = netdev_priv(dev); 1203 1204 if (cmd != SIOCDEL6RD) { 1205 err = ipip6_tunnel_update_6rd(t, &ip6rd); 1206 if (err < 0) 1207 goto done; 1208 } else 1209 ipip6_tunnel_clone_6rd(dev, sitn); 1210 1211 err = 0; 1212 break; 1213 #endif 1214 1215 default: 1216 err = -EINVAL; 1217 } 1218 1219 done: 1220 return err; 1221 } 1222 1223 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1224 { 1225 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr)) 1226 return -EINVAL; 1227 dev->mtu = new_mtu; 1228 return 0; 1229 } 1230 1231 static const struct net_device_ops ipip6_netdev_ops = { 1232 .ndo_uninit = ipip6_tunnel_uninit, 1233 .ndo_start_xmit = sit_tunnel_xmit, 1234 .ndo_do_ioctl = ipip6_tunnel_ioctl, 1235 .ndo_change_mtu = ipip6_tunnel_change_mtu, 1236 .ndo_get_stats64 = ip_tunnel_get_stats64, 1237 }; 1238 1239 static void ipip6_dev_free(struct net_device *dev) 1240 { 1241 free_percpu(dev->tstats); 1242 free_netdev(dev); 1243 } 1244 1245 static void ipip6_tunnel_setup(struct net_device *dev) 1246 { 1247 dev->netdev_ops = &ipip6_netdev_ops; 1248 dev->destructor = ipip6_dev_free; 1249 1250 dev->type = ARPHRD_SIT; 1251 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr); 1252 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr); 1253 dev->flags = IFF_NOARP; 1254 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1255 dev->iflink = 0; 1256 dev->addr_len = 4; 1257 dev->features |= NETIF_F_LLTX; 1258 } 1259 1260 static int ipip6_tunnel_init(struct net_device *dev) 1261 { 1262 struct ip_tunnel *tunnel = netdev_priv(dev); 1263 1264 tunnel->dev = dev; 1265 tunnel->net = dev_net(dev); 1266 1267 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); 1268 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); 1269 1270 ipip6_tunnel_bind_dev(dev); 1271 dev->tstats = alloc_percpu(struct pcpu_tstats); 1272 if (!dev->tstats) 1273 return -ENOMEM; 1274 1275 return 0; 1276 } 1277 1278 static int __net_init ipip6_fb_tunnel_init(struct net_device *dev) 1279 { 1280 struct ip_tunnel *tunnel = netdev_priv(dev); 1281 struct iphdr *iph = &tunnel->parms.iph; 1282 struct net *net = dev_net(dev); 1283 struct sit_net *sitn = net_generic(net, sit_net_id); 1284 1285 tunnel->dev = dev; 1286 tunnel->net = dev_net(dev); 1287 strcpy(tunnel->parms.name, dev->name); 1288 1289 iph->version = 4; 1290 iph->protocol = IPPROTO_IPV6; 1291 iph->ihl = 5; 1292 iph->ttl = 64; 1293 1294 dev->tstats = alloc_percpu(struct pcpu_tstats); 1295 if (!dev->tstats) 1296 return -ENOMEM; 1297 dev_hold(dev); 1298 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel); 1299 return 0; 1300 } 1301 1302 static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[]) 1303 { 1304 u8 proto; 1305 1306 if (!data || !data[IFLA_IPTUN_PROTO]) 1307 return 0; 1308 1309 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1310 if (proto != IPPROTO_IPV6 && 1311 proto != IPPROTO_IPIP && 1312 proto != 0) 1313 return -EINVAL; 1314 1315 return 0; 1316 } 1317 1318 static void ipip6_netlink_parms(struct nlattr *data[], 1319 struct ip_tunnel_parm *parms) 1320 { 1321 memset(parms, 0, sizeof(*parms)); 1322 1323 parms->iph.version = 4; 1324 parms->iph.protocol = IPPROTO_IPV6; 1325 parms->iph.ihl = 5; 1326 parms->iph.ttl = 64; 1327 1328 if (!data) 1329 return; 1330 1331 if (data[IFLA_IPTUN_LINK]) 1332 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); 1333 1334 if (data[IFLA_IPTUN_LOCAL]) 1335 parms->iph.saddr = nla_get_be32(data[IFLA_IPTUN_LOCAL]); 1336 1337 if (data[IFLA_IPTUN_REMOTE]) 1338 parms->iph.daddr = nla_get_be32(data[IFLA_IPTUN_REMOTE]); 1339 1340 if (data[IFLA_IPTUN_TTL]) { 1341 parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]); 1342 if (parms->iph.ttl) 1343 parms->iph.frag_off = htons(IP_DF); 1344 } 1345 1346 if (data[IFLA_IPTUN_TOS]) 1347 parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]); 1348 1349 if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC])) 1350 parms->iph.frag_off = htons(IP_DF); 1351 1352 if (data[IFLA_IPTUN_FLAGS]) 1353 parms->i_flags = nla_get_be16(data[IFLA_IPTUN_FLAGS]); 1354 1355 if (data[IFLA_IPTUN_PROTO]) 1356 parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]); 1357 1358 } 1359 1360 #ifdef CONFIG_IPV6_SIT_6RD 1361 /* This function returns true when 6RD attributes are present in the nl msg */ 1362 static bool ipip6_netlink_6rd_parms(struct nlattr *data[], 1363 struct ip_tunnel_6rd *ip6rd) 1364 { 1365 bool ret = false; 1366 memset(ip6rd, 0, sizeof(*ip6rd)); 1367 1368 if (!data) 1369 return ret; 1370 1371 if (data[IFLA_IPTUN_6RD_PREFIX]) { 1372 ret = true; 1373 nla_memcpy(&ip6rd->prefix, data[IFLA_IPTUN_6RD_PREFIX], 1374 sizeof(struct in6_addr)); 1375 } 1376 1377 if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) { 1378 ret = true; 1379 ip6rd->relay_prefix = 1380 nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]); 1381 } 1382 1383 if (data[IFLA_IPTUN_6RD_PREFIXLEN]) { 1384 ret = true; 1385 ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]); 1386 } 1387 1388 if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) { 1389 ret = true; 1390 ip6rd->relay_prefixlen = 1391 nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]); 1392 } 1393 1394 return ret; 1395 } 1396 #endif 1397 1398 static int ipip6_newlink(struct net *src_net, struct net_device *dev, 1399 struct nlattr *tb[], struct nlattr *data[]) 1400 { 1401 struct net *net = dev_net(dev); 1402 struct ip_tunnel *nt; 1403 #ifdef CONFIG_IPV6_SIT_6RD 1404 struct ip_tunnel_6rd ip6rd; 1405 #endif 1406 int err; 1407 1408 nt = netdev_priv(dev); 1409 ipip6_netlink_parms(data, &nt->parms); 1410 1411 if (ipip6_tunnel_locate(net, &nt->parms, 0)) 1412 return -EEXIST; 1413 1414 err = ipip6_tunnel_create(dev); 1415 if (err < 0) 1416 return err; 1417 1418 #ifdef CONFIG_IPV6_SIT_6RD 1419 if (ipip6_netlink_6rd_parms(data, &ip6rd)) 1420 err = ipip6_tunnel_update_6rd(nt, &ip6rd); 1421 #endif 1422 1423 return err; 1424 } 1425 1426 static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[], 1427 struct nlattr *data[]) 1428 { 1429 struct ip_tunnel *t = netdev_priv(dev); 1430 struct ip_tunnel_parm p; 1431 struct net *net = t->net; 1432 struct sit_net *sitn = net_generic(net, sit_net_id); 1433 #ifdef CONFIG_IPV6_SIT_6RD 1434 struct ip_tunnel_6rd ip6rd; 1435 #endif 1436 1437 if (dev == sitn->fb_tunnel_dev) 1438 return -EINVAL; 1439 1440 ipip6_netlink_parms(data, &p); 1441 1442 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) || 1443 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr)) 1444 return -EINVAL; 1445 1446 t = ipip6_tunnel_locate(net, &p, 0); 1447 1448 if (t) { 1449 if (t->dev != dev) 1450 return -EEXIST; 1451 } else 1452 t = netdev_priv(dev); 1453 1454 ipip6_tunnel_update(t, &p); 1455 1456 #ifdef CONFIG_IPV6_SIT_6RD 1457 if (ipip6_netlink_6rd_parms(data, &ip6rd)) 1458 return ipip6_tunnel_update_6rd(t, &ip6rd); 1459 #endif 1460 1461 return 0; 1462 } 1463 1464 static size_t ipip6_get_size(const struct net_device *dev) 1465 { 1466 return 1467 /* IFLA_IPTUN_LINK */ 1468 nla_total_size(4) + 1469 /* IFLA_IPTUN_LOCAL */ 1470 nla_total_size(4) + 1471 /* IFLA_IPTUN_REMOTE */ 1472 nla_total_size(4) + 1473 /* IFLA_IPTUN_TTL */ 1474 nla_total_size(1) + 1475 /* IFLA_IPTUN_TOS */ 1476 nla_total_size(1) + 1477 /* IFLA_IPTUN_PMTUDISC */ 1478 nla_total_size(1) + 1479 /* IFLA_IPTUN_FLAGS */ 1480 nla_total_size(2) + 1481 /* IFLA_IPTUN_PROTO */ 1482 nla_total_size(1) + 1483 #ifdef CONFIG_IPV6_SIT_6RD 1484 /* IFLA_IPTUN_6RD_PREFIX */ 1485 nla_total_size(sizeof(struct in6_addr)) + 1486 /* IFLA_IPTUN_6RD_RELAY_PREFIX */ 1487 nla_total_size(4) + 1488 /* IFLA_IPTUN_6RD_PREFIXLEN */ 1489 nla_total_size(2) + 1490 /* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */ 1491 nla_total_size(2) + 1492 #endif 1493 0; 1494 } 1495 1496 static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev) 1497 { 1498 struct ip_tunnel *tunnel = netdev_priv(dev); 1499 struct ip_tunnel_parm *parm = &tunnel->parms; 1500 1501 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 1502 nla_put_be32(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) || 1503 nla_put_be32(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) || 1504 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) || 1505 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) || 1506 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC, 1507 !!(parm->iph.frag_off & htons(IP_DF))) || 1508 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) || 1509 nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags)) 1510 goto nla_put_failure; 1511 1512 #ifdef CONFIG_IPV6_SIT_6RD 1513 if (nla_put(skb, IFLA_IPTUN_6RD_PREFIX, sizeof(struct in6_addr), 1514 &tunnel->ip6rd.prefix) || 1515 nla_put_be32(skb, IFLA_IPTUN_6RD_RELAY_PREFIX, 1516 tunnel->ip6rd.relay_prefix) || 1517 nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN, 1518 tunnel->ip6rd.prefixlen) || 1519 nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN, 1520 tunnel->ip6rd.relay_prefixlen)) 1521 goto nla_put_failure; 1522 #endif 1523 1524 return 0; 1525 1526 nla_put_failure: 1527 return -EMSGSIZE; 1528 } 1529 1530 static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = { 1531 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 1532 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 }, 1533 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 }, 1534 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 1535 [IFLA_IPTUN_TOS] = { .type = NLA_U8 }, 1536 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 }, 1537 [IFLA_IPTUN_FLAGS] = { .type = NLA_U16 }, 1538 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 1539 #ifdef CONFIG_IPV6_SIT_6RD 1540 [IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) }, 1541 [IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 }, 1542 [IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 }, 1543 [IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 }, 1544 #endif 1545 }; 1546 1547 static struct rtnl_link_ops sit_link_ops __read_mostly = { 1548 .kind = "sit", 1549 .maxtype = IFLA_IPTUN_MAX, 1550 .policy = ipip6_policy, 1551 .priv_size = sizeof(struct ip_tunnel), 1552 .setup = ipip6_tunnel_setup, 1553 .validate = ipip6_validate, 1554 .newlink = ipip6_newlink, 1555 .changelink = ipip6_changelink, 1556 .get_size = ipip6_get_size, 1557 .fill_info = ipip6_fill_info, 1558 }; 1559 1560 static struct xfrm_tunnel sit_handler __read_mostly = { 1561 .handler = ipip6_rcv, 1562 .err_handler = ipip6_err, 1563 .priority = 1, 1564 }; 1565 1566 static struct xfrm_tunnel ipip_handler __read_mostly = { 1567 .handler = ipip_rcv, 1568 .err_handler = ipip6_err, 1569 .priority = 2, 1570 }; 1571 1572 static void __net_exit sit_destroy_tunnels(struct sit_net *sitn, struct list_head *head) 1573 { 1574 struct net *net = dev_net(sitn->fb_tunnel_dev); 1575 struct net_device *dev, *aux; 1576 int prio; 1577 1578 for_each_netdev_safe(net, dev, aux) 1579 if (dev->rtnl_link_ops == &sit_link_ops) 1580 unregister_netdevice_queue(dev, head); 1581 1582 for (prio = 1; prio < 4; prio++) { 1583 int h; 1584 for (h = 0; h < HASH_SIZE; h++) { 1585 struct ip_tunnel *t; 1586 1587 t = rtnl_dereference(sitn->tunnels[prio][h]); 1588 while (t != NULL) { 1589 /* If dev is in the same netns, it has already 1590 * been added to the list by the previous loop. 1591 */ 1592 if (dev_net(t->dev) != net) 1593 unregister_netdevice_queue(t->dev, 1594 head); 1595 t = rtnl_dereference(t->next); 1596 } 1597 } 1598 } 1599 } 1600 1601 static int __net_init sit_init_net(struct net *net) 1602 { 1603 struct sit_net *sitn = net_generic(net, sit_net_id); 1604 struct ip_tunnel *t; 1605 int err; 1606 1607 sitn->tunnels[0] = sitn->tunnels_wc; 1608 sitn->tunnels[1] = sitn->tunnels_l; 1609 sitn->tunnels[2] = sitn->tunnels_r; 1610 sitn->tunnels[3] = sitn->tunnels_r_l; 1611 1612 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0", 1613 ipip6_tunnel_setup); 1614 if (!sitn->fb_tunnel_dev) { 1615 err = -ENOMEM; 1616 goto err_alloc_dev; 1617 } 1618 dev_net_set(sitn->fb_tunnel_dev, net); 1619 /* FB netdevice is special: we have one, and only one per netns. 1620 * Allowing to move it to another netns is clearly unsafe. 1621 */ 1622 sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1623 1624 err = ipip6_fb_tunnel_init(sitn->fb_tunnel_dev); 1625 if (err) 1626 goto err_dev_free; 1627 1628 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn); 1629 1630 if ((err = register_netdev(sitn->fb_tunnel_dev))) 1631 goto err_reg_dev; 1632 1633 t = netdev_priv(sitn->fb_tunnel_dev); 1634 1635 strcpy(t->parms.name, sitn->fb_tunnel_dev->name); 1636 return 0; 1637 1638 err_reg_dev: 1639 dev_put(sitn->fb_tunnel_dev); 1640 err_dev_free: 1641 ipip6_dev_free(sitn->fb_tunnel_dev); 1642 err_alloc_dev: 1643 return err; 1644 } 1645 1646 static void __net_exit sit_exit_net(struct net *net) 1647 { 1648 struct sit_net *sitn = net_generic(net, sit_net_id); 1649 LIST_HEAD(list); 1650 1651 rtnl_lock(); 1652 sit_destroy_tunnels(sitn, &list); 1653 unregister_netdevice_queue(sitn->fb_tunnel_dev, &list); 1654 unregister_netdevice_many(&list); 1655 rtnl_unlock(); 1656 } 1657 1658 static struct pernet_operations sit_net_ops = { 1659 .init = sit_init_net, 1660 .exit = sit_exit_net, 1661 .id = &sit_net_id, 1662 .size = sizeof(struct sit_net), 1663 }; 1664 1665 static void __exit sit_cleanup(void) 1666 { 1667 rtnl_link_unregister(&sit_link_ops); 1668 xfrm4_tunnel_deregister(&sit_handler, AF_INET6); 1669 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 1670 1671 unregister_pernet_device(&sit_net_ops); 1672 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1673 } 1674 1675 static int __init sit_init(void) 1676 { 1677 int err; 1678 1679 pr_info("IPv6 over IPv4 tunneling driver\n"); 1680 1681 err = register_pernet_device(&sit_net_ops); 1682 if (err < 0) 1683 return err; 1684 err = xfrm4_tunnel_register(&sit_handler, AF_INET6); 1685 if (err < 0) { 1686 pr_info("%s: can't register ip6ip4\n", __func__); 1687 goto xfrm_tunnel_failed; 1688 } 1689 err = xfrm4_tunnel_register(&ipip_handler, AF_INET); 1690 if (err < 0) { 1691 pr_info("%s: can't register ip4ip4\n", __func__); 1692 goto xfrm_tunnel4_failed; 1693 } 1694 err = rtnl_link_register(&sit_link_ops); 1695 if (err < 0) 1696 goto rtnl_link_failed; 1697 1698 out: 1699 return err; 1700 1701 rtnl_link_failed: 1702 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 1703 xfrm_tunnel4_failed: 1704 xfrm4_tunnel_deregister(&sit_handler, AF_INET6); 1705 xfrm_tunnel_failed: 1706 unregister_pernet_device(&sit_net_ops); 1707 goto out; 1708 } 1709 1710 module_init(sit_init); 1711 module_exit(sit_cleanup); 1712 MODULE_LICENSE("GPL"); 1713 MODULE_ALIAS_NETDEV("sit0"); 1714