1 /* 2 * IPv6 virtual tunneling interface 3 * 4 * Copyright (C) 2013 secunet Security Networks AG 5 * 6 * Author: 7 * Steffen Klassert <steffen.klassert@secunet.com> 8 * 9 * Based on: 10 * net/ipv6/ip6_tunnel.c 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * as published by the Free Software Foundation; either version 15 * 2 of the License, or (at your option) any later version. 16 */ 17 18 #include <linux/module.h> 19 #include <linux/capability.h> 20 #include <linux/errno.h> 21 #include <linux/types.h> 22 #include <linux/sockios.h> 23 #include <linux/icmp.h> 24 #include <linux/if.h> 25 #include <linux/in.h> 26 #include <linux/ip.h> 27 #include <linux/net.h> 28 #include <linux/in6.h> 29 #include <linux/netdevice.h> 30 #include <linux/if_arp.h> 31 #include <linux/icmpv6.h> 32 #include <linux/init.h> 33 #include <linux/route.h> 34 #include <linux/rtnetlink.h> 35 #include <linux/netfilter_ipv6.h> 36 #include <linux/slab.h> 37 #include <linux/hash.h> 38 39 #include <linux/uaccess.h> 40 #include <linux/atomic.h> 41 42 #include <net/icmp.h> 43 #include <net/ip.h> 44 #include <net/ip_tunnels.h> 45 #include <net/ipv6.h> 46 #include <net/ip6_route.h> 47 #include <net/addrconf.h> 48 #include <net/ip6_tunnel.h> 49 #include <net/xfrm.h> 50 #include <net/net_namespace.h> 51 #include <net/netns/generic.h> 52 53 #define HASH_SIZE_SHIFT 5 54 #define HASH_SIZE (1 << HASH_SIZE_SHIFT) 55 56 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) 57 { 58 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); 59 60 return hash_32(hash, HASH_SIZE_SHIFT); 61 } 62 63 static int vti6_dev_init(struct net_device *dev); 64 static void vti6_dev_setup(struct net_device *dev); 65 static struct rtnl_link_ops vti6_link_ops __read_mostly; 66 67 static int vti6_net_id __read_mostly; 68 struct vti6_net { 69 /* the vti6 tunnel fallback device */ 70 struct net_device *fb_tnl_dev; 71 /* lists for storing tunnels in use */ 72 struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE]; 73 struct ip6_tnl __rcu *tnls_wc[1]; 74 struct ip6_tnl __rcu **tnls[2]; 75 }; 76 77 #define for_each_vti6_tunnel_rcu(start) \ 78 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 79 80 /** 81 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses 82 * @net: network namespace 83 * @remote: the address of the tunnel exit-point 84 * @local: the address of the tunnel entry-point 85 * 86 * Return: 87 * tunnel matching given end-points if found, 88 * else fallback tunnel if its device is up, 89 * else %NULL 90 **/ 91 static struct ip6_tnl * 92 vti6_tnl_lookup(struct net *net, const struct in6_addr *remote, 93 const struct in6_addr *local) 94 { 95 unsigned int hash = HASH(remote, local); 96 struct ip6_tnl *t; 97 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 98 struct in6_addr any; 99 100 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 101 if (ipv6_addr_equal(local, &t->parms.laddr) && 102 ipv6_addr_equal(remote, &t->parms.raddr) && 103 (t->dev->flags & IFF_UP)) 104 return t; 105 } 106 107 memset(&any, 0, sizeof(any)); 108 hash = HASH(&any, local); 109 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 110 if (ipv6_addr_equal(local, &t->parms.laddr) && 111 (t->dev->flags & IFF_UP)) 112 return t; 113 } 114 115 hash = HASH(remote, &any); 116 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 117 if (ipv6_addr_equal(remote, &t->parms.raddr) && 118 (t->dev->flags & IFF_UP)) 119 return t; 120 } 121 122 t = rcu_dereference(ip6n->tnls_wc[0]); 123 if (t && (t->dev->flags & IFF_UP)) 124 return t; 125 126 return NULL; 127 } 128 129 /** 130 * vti6_tnl_bucket - get head of list matching given tunnel parameters 131 * @p: parameters containing tunnel end-points 132 * 133 * Description: 134 * vti6_tnl_bucket() returns the head of the list matching the 135 * &struct in6_addr entries laddr and raddr in @p. 136 * 137 * Return: head of IPv6 tunnel list 138 **/ 139 static struct ip6_tnl __rcu ** 140 vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p) 141 { 142 const struct in6_addr *remote = &p->raddr; 143 const struct in6_addr *local = &p->laddr; 144 unsigned int h = 0; 145 int prio = 0; 146 147 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 148 prio = 1; 149 h = HASH(remote, local); 150 } 151 return &ip6n->tnls[prio][h]; 152 } 153 154 static void 155 vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t) 156 { 157 struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms); 158 159 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 160 rcu_assign_pointer(*tp, t); 161 } 162 163 static void 164 vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t) 165 { 166 struct ip6_tnl __rcu **tp; 167 struct ip6_tnl *iter; 168 169 for (tp = vti6_tnl_bucket(ip6n, &t->parms); 170 (iter = rtnl_dereference(*tp)) != NULL; 171 tp = &iter->next) { 172 if (t == iter) { 173 rcu_assign_pointer(*tp, t->next); 174 break; 175 } 176 } 177 } 178 179 static void vti6_dev_free(struct net_device *dev) 180 { 181 free_percpu(dev->tstats); 182 free_netdev(dev); 183 } 184 185 static int vti6_tnl_create2(struct net_device *dev) 186 { 187 struct ip6_tnl *t = netdev_priv(dev); 188 struct net *net = dev_net(dev); 189 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 190 int err; 191 192 err = register_netdevice(dev); 193 if (err < 0) 194 goto out; 195 196 strcpy(t->parms.name, dev->name); 197 dev->rtnl_link_ops = &vti6_link_ops; 198 199 dev_hold(dev); 200 vti6_tnl_link(ip6n, t); 201 202 return 0; 203 204 out: 205 return err; 206 } 207 208 static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) 209 { 210 struct net_device *dev; 211 struct ip6_tnl *t; 212 char name[IFNAMSIZ]; 213 int err; 214 215 if (p->name[0]) 216 strlcpy(name, p->name, IFNAMSIZ); 217 else 218 sprintf(name, "ip6_vti%%d"); 219 220 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup); 221 if (dev == NULL) 222 goto failed; 223 224 dev_net_set(dev, net); 225 226 t = netdev_priv(dev); 227 t->parms = *p; 228 t->net = dev_net(dev); 229 230 err = vti6_tnl_create2(dev); 231 if (err < 0) 232 goto failed_free; 233 234 return t; 235 236 failed_free: 237 vti6_dev_free(dev); 238 failed: 239 return NULL; 240 } 241 242 /** 243 * vti6_locate - find or create tunnel matching given parameters 244 * @net: network namespace 245 * @p: tunnel parameters 246 * @create: != 0 if allowed to create new tunnel if no match found 247 * 248 * Description: 249 * vti6_locate() first tries to locate an existing tunnel 250 * based on @parms. If this is unsuccessful, but @create is set a new 251 * tunnel device is created and registered for use. 252 * 253 * Return: 254 * matching tunnel or NULL 255 **/ 256 static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p, 257 int create) 258 { 259 const struct in6_addr *remote = &p->raddr; 260 const struct in6_addr *local = &p->laddr; 261 struct ip6_tnl __rcu **tp; 262 struct ip6_tnl *t; 263 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 264 265 for (tp = vti6_tnl_bucket(ip6n, p); 266 (t = rtnl_dereference(*tp)) != NULL; 267 tp = &t->next) { 268 if (ipv6_addr_equal(local, &t->parms.laddr) && 269 ipv6_addr_equal(remote, &t->parms.raddr)) { 270 if (create) 271 return NULL; 272 273 return t; 274 } 275 } 276 if (!create) 277 return NULL; 278 return vti6_tnl_create(net, p); 279 } 280 281 /** 282 * vti6_dev_uninit - tunnel device uninitializer 283 * @dev: the device to be destroyed 284 * 285 * Description: 286 * vti6_dev_uninit() removes tunnel from its list 287 **/ 288 static void vti6_dev_uninit(struct net_device *dev) 289 { 290 struct ip6_tnl *t = netdev_priv(dev); 291 struct net *net = dev_net(dev); 292 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 293 294 if (dev == ip6n->fb_tnl_dev) 295 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 296 else 297 vti6_tnl_unlink(ip6n, t); 298 dev_put(dev); 299 } 300 301 static int vti6_rcv(struct sk_buff *skb) 302 { 303 struct ip6_tnl *t; 304 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 305 306 rcu_read_lock(); 307 t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr); 308 if (t != NULL) { 309 if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) { 310 rcu_read_unlock(); 311 goto discard; 312 } 313 314 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 315 rcu_read_unlock(); 316 return 0; 317 } 318 319 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { 320 t->dev->stats.rx_dropped++; 321 rcu_read_unlock(); 322 goto discard; 323 } 324 325 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; 326 skb->mark = be32_to_cpu(t->parms.i_key); 327 328 rcu_read_unlock(); 329 330 return xfrm6_rcv(skb); 331 } 332 rcu_read_unlock(); 333 return -EINVAL; 334 discard: 335 kfree_skb(skb); 336 return 0; 337 } 338 339 static int vti6_rcv_cb(struct sk_buff *skb, int err) 340 { 341 unsigned short family; 342 struct net_device *dev; 343 struct pcpu_sw_netstats *tstats; 344 struct xfrm_state *x; 345 struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6; 346 347 if (!t) 348 return 1; 349 350 dev = t->dev; 351 352 if (err) { 353 dev->stats.rx_errors++; 354 dev->stats.rx_dropped++; 355 356 return 0; 357 } 358 359 x = xfrm_input_state(skb); 360 family = x->inner_mode->afinfo->family; 361 362 if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family)) 363 return -EPERM; 364 365 skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev))); 366 skb->dev = dev; 367 368 tstats = this_cpu_ptr(dev->tstats); 369 u64_stats_update_begin(&tstats->syncp); 370 tstats->rx_packets++; 371 tstats->rx_bytes += skb->len; 372 u64_stats_update_end(&tstats->syncp); 373 374 return 0; 375 } 376 377 /** 378 * vti6_addr_conflict - compare packet addresses to tunnel's own 379 * @t: the outgoing tunnel device 380 * @hdr: IPv6 header from the incoming packet 381 * 382 * Description: 383 * Avoid trivial tunneling loop by checking that tunnel exit-point 384 * doesn't match source of incoming packet. 385 * 386 * Return: 387 * 1 if conflict, 388 * 0 else 389 **/ 390 static inline bool 391 vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 392 { 393 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 394 } 395 396 static bool vti6_state_check(const struct xfrm_state *x, 397 const struct in6_addr *dst, 398 const struct in6_addr *src) 399 { 400 xfrm_address_t *daddr = (xfrm_address_t *)dst; 401 xfrm_address_t *saddr = (xfrm_address_t *)src; 402 403 /* if there is no transform then this tunnel is not functional. 404 * Or if the xfrm is not mode tunnel. 405 */ 406 if (!x || x->props.mode != XFRM_MODE_TUNNEL || 407 x->props.family != AF_INET6) 408 return false; 409 410 if (ipv6_addr_any(dst)) 411 return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6); 412 413 if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6)) 414 return false; 415 416 return true; 417 } 418 419 /** 420 * vti6_xmit - send a packet 421 * @skb: the outgoing socket buffer 422 * @dev: the outgoing tunnel device 423 * @fl: the flow informations for the xfrm_lookup 424 **/ 425 static int 426 vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) 427 { 428 struct ip6_tnl *t = netdev_priv(dev); 429 struct net_device_stats *stats = &t->dev->stats; 430 struct dst_entry *dst = skb_dst(skb); 431 struct net_device *tdev; 432 struct xfrm_state *x; 433 int err = -1; 434 435 if (!dst) 436 goto tx_err_link_failure; 437 438 dst_hold(dst); 439 dst = xfrm_lookup(t->net, dst, fl, NULL, 0); 440 if (IS_ERR(dst)) { 441 err = PTR_ERR(dst); 442 dst = NULL; 443 goto tx_err_link_failure; 444 } 445 446 x = dst->xfrm; 447 if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr)) 448 goto tx_err_link_failure; 449 450 if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr, 451 (const struct in6_addr *)&x->id.daddr)) 452 goto tx_err_link_failure; 453 454 tdev = dst->dev; 455 456 if (tdev == dev) { 457 stats->collisions++; 458 net_warn_ratelimited("%s: Local routing loop detected!\n", 459 t->parms.name); 460 goto tx_err_dst_release; 461 } 462 463 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 464 skb_dst_set(skb, dst); 465 skb->dev = skb_dst(skb)->dev; 466 467 err = dst_output(skb); 468 if (net_xmit_eval(err) == 0) { 469 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats); 470 471 u64_stats_update_begin(&tstats->syncp); 472 tstats->tx_bytes += skb->len; 473 tstats->tx_packets++; 474 u64_stats_update_end(&tstats->syncp); 475 } else { 476 stats->tx_errors++; 477 stats->tx_aborted_errors++; 478 } 479 480 return 0; 481 tx_err_link_failure: 482 stats->tx_carrier_errors++; 483 dst_link_failure(skb); 484 tx_err_dst_release: 485 dst_release(dst); 486 return err; 487 } 488 489 static netdev_tx_t 490 vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 491 { 492 struct ip6_tnl *t = netdev_priv(dev); 493 struct net_device_stats *stats = &t->dev->stats; 494 struct ipv6hdr *ipv6h; 495 struct flowi fl; 496 int ret; 497 498 memset(&fl, 0, sizeof(fl)); 499 skb->mark = be32_to_cpu(t->parms.o_key); 500 501 switch (skb->protocol) { 502 case htons(ETH_P_IPV6): 503 ipv6h = ipv6_hdr(skb); 504 505 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 506 vti6_addr_conflict(t, ipv6h)) 507 goto tx_err; 508 509 xfrm_decode_session(skb, &fl, AF_INET6); 510 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); 511 break; 512 case htons(ETH_P_IP): 513 xfrm_decode_session(skb, &fl, AF_INET); 514 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 515 break; 516 default: 517 goto tx_err; 518 } 519 520 ret = vti6_xmit(skb, dev, &fl); 521 if (ret < 0) 522 goto tx_err; 523 524 return NETDEV_TX_OK; 525 526 tx_err: 527 stats->tx_errors++; 528 stats->tx_dropped++; 529 kfree_skb(skb); 530 return NETDEV_TX_OK; 531 } 532 533 static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 534 u8 type, u8 code, int offset, __be32 info) 535 { 536 __be32 spi; 537 __u32 mark; 538 struct xfrm_state *x; 539 struct ip6_tnl *t; 540 struct ip_esp_hdr *esph; 541 struct ip_auth_hdr *ah; 542 struct ip_comp_hdr *ipch; 543 struct net *net = dev_net(skb->dev); 544 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 545 int protocol = iph->nexthdr; 546 547 t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr); 548 if (!t) 549 return -1; 550 551 mark = be32_to_cpu(t->parms.o_key); 552 553 switch (protocol) { 554 case IPPROTO_ESP: 555 esph = (struct ip_esp_hdr *)(skb->data + offset); 556 spi = esph->spi; 557 break; 558 case IPPROTO_AH: 559 ah = (struct ip_auth_hdr *)(skb->data + offset); 560 spi = ah->spi; 561 break; 562 case IPPROTO_COMP: 563 ipch = (struct ip_comp_hdr *)(skb->data + offset); 564 spi = htonl(ntohs(ipch->cpi)); 565 break; 566 default: 567 return 0; 568 } 569 570 if (type != ICMPV6_PKT_TOOBIG && 571 type != NDISC_REDIRECT) 572 return 0; 573 574 x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr, 575 spi, protocol, AF_INET6); 576 if (!x) 577 return 0; 578 579 if (type == NDISC_REDIRECT) 580 ip6_redirect(skb, net, skb->dev->ifindex, 0); 581 else 582 ip6_update_pmtu(skb, net, info, 0, 0); 583 xfrm_state_put(x); 584 585 return 0; 586 } 587 588 static void vti6_link_config(struct ip6_tnl *t) 589 { 590 struct net_device *dev = t->dev; 591 struct __ip6_tnl_parm *p = &t->parms; 592 593 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 594 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 595 596 p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV | 597 IP6_TNL_F_CAP_PER_PACKET); 598 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 599 600 if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV) 601 dev->flags |= IFF_POINTOPOINT; 602 else 603 dev->flags &= ~IFF_POINTOPOINT; 604 605 dev->iflink = p->link; 606 } 607 608 /** 609 * vti6_tnl_change - update the tunnel parameters 610 * @t: tunnel to be changed 611 * @p: tunnel configuration parameters 612 * 613 * Description: 614 * vti6_tnl_change() updates the tunnel parameters 615 **/ 616 static int 617 vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 618 { 619 t->parms.laddr = p->laddr; 620 t->parms.raddr = p->raddr; 621 t->parms.link = p->link; 622 t->parms.i_key = p->i_key; 623 t->parms.o_key = p->o_key; 624 t->parms.proto = p->proto; 625 ip6_tnl_dst_reset(t); 626 vti6_link_config(t); 627 return 0; 628 } 629 630 static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 631 { 632 struct net *net = dev_net(t->dev); 633 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 634 int err; 635 636 vti6_tnl_unlink(ip6n, t); 637 synchronize_net(); 638 err = vti6_tnl_change(t, p); 639 vti6_tnl_link(ip6n, t); 640 netdev_state_change(t->dev); 641 return err; 642 } 643 644 static void 645 vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u) 646 { 647 p->laddr = u->laddr; 648 p->raddr = u->raddr; 649 p->link = u->link; 650 p->i_key = u->i_key; 651 p->o_key = u->o_key; 652 p->proto = u->proto; 653 654 memcpy(p->name, u->name, sizeof(u->name)); 655 } 656 657 static void 658 vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p) 659 { 660 u->laddr = p->laddr; 661 u->raddr = p->raddr; 662 u->link = p->link; 663 u->i_key = p->i_key; 664 u->o_key = p->o_key; 665 u->proto = p->proto; 666 667 memcpy(u->name, p->name, sizeof(u->name)); 668 } 669 670 /** 671 * vti6_tnl_ioctl - configure vti6 tunnels from userspace 672 * @dev: virtual device associated with tunnel 673 * @ifr: parameters passed from userspace 674 * @cmd: command to be performed 675 * 676 * Description: 677 * vti6_ioctl() is used for managing vti6 tunnels 678 * from userspace. 679 * 680 * The possible commands are the following: 681 * %SIOCGETTUNNEL: get tunnel parameters for device 682 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 683 * %SIOCCHGTUNNEL: change tunnel parameters to those given 684 * %SIOCDELTUNNEL: delete tunnel 685 * 686 * The fallback device "ip6_vti0", created during module 687 * initialization, can be used for creating other tunnel devices. 688 * 689 * Return: 690 * 0 on success, 691 * %-EFAULT if unable to copy data to or from userspace, 692 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 693 * %-EINVAL if passed tunnel parameters are invalid, 694 * %-EEXIST if changing a tunnel's parameters would cause a conflict 695 * %-ENODEV if attempting to change or delete a nonexisting device 696 **/ 697 static int 698 vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 699 { 700 int err = 0; 701 struct ip6_tnl_parm2 p; 702 struct __ip6_tnl_parm p1; 703 struct ip6_tnl *t = NULL; 704 struct net *net = dev_net(dev); 705 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 706 707 switch (cmd) { 708 case SIOCGETTUNNEL: 709 if (dev == ip6n->fb_tnl_dev) { 710 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 711 err = -EFAULT; 712 break; 713 } 714 vti6_parm_from_user(&p1, &p); 715 t = vti6_locate(net, &p1, 0); 716 } else { 717 memset(&p, 0, sizeof(p)); 718 } 719 if (t == NULL) 720 t = netdev_priv(dev); 721 vti6_parm_to_user(&p, &t->parms); 722 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 723 err = -EFAULT; 724 break; 725 case SIOCADDTUNNEL: 726 case SIOCCHGTUNNEL: 727 err = -EPERM; 728 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 729 break; 730 err = -EFAULT; 731 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 732 break; 733 err = -EINVAL; 734 if (p.proto != IPPROTO_IPV6 && p.proto != 0) 735 break; 736 vti6_parm_from_user(&p1, &p); 737 t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL); 738 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 739 if (t != NULL) { 740 if (t->dev != dev) { 741 err = -EEXIST; 742 break; 743 } 744 } else 745 t = netdev_priv(dev); 746 747 err = vti6_update(t, &p1); 748 } 749 if (t) { 750 err = 0; 751 vti6_parm_to_user(&p, &t->parms); 752 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 753 err = -EFAULT; 754 755 } else 756 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 757 break; 758 case SIOCDELTUNNEL: 759 err = -EPERM; 760 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 761 break; 762 763 if (dev == ip6n->fb_tnl_dev) { 764 err = -EFAULT; 765 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 766 break; 767 err = -ENOENT; 768 vti6_parm_from_user(&p1, &p); 769 t = vti6_locate(net, &p1, 0); 770 if (t == NULL) 771 break; 772 err = -EPERM; 773 if (t->dev == ip6n->fb_tnl_dev) 774 break; 775 dev = t->dev; 776 } 777 err = 0; 778 unregister_netdevice(dev); 779 break; 780 default: 781 err = -EINVAL; 782 } 783 return err; 784 } 785 786 /** 787 * vti6_tnl_change_mtu - change mtu manually for tunnel device 788 * @dev: virtual device associated with tunnel 789 * @new_mtu: the new mtu 790 * 791 * Return: 792 * 0 on success, 793 * %-EINVAL if mtu too small 794 **/ 795 static int vti6_change_mtu(struct net_device *dev, int new_mtu) 796 { 797 if (new_mtu < IPV6_MIN_MTU) 798 return -EINVAL; 799 800 dev->mtu = new_mtu; 801 return 0; 802 } 803 804 static const struct net_device_ops vti6_netdev_ops = { 805 .ndo_init = vti6_dev_init, 806 .ndo_uninit = vti6_dev_uninit, 807 .ndo_start_xmit = vti6_tnl_xmit, 808 .ndo_do_ioctl = vti6_ioctl, 809 .ndo_change_mtu = vti6_change_mtu, 810 .ndo_get_stats64 = ip_tunnel_get_stats64, 811 }; 812 813 /** 814 * vti6_dev_setup - setup virtual tunnel device 815 * @dev: virtual device associated with tunnel 816 * 817 * Description: 818 * Initialize function pointers and device parameters 819 **/ 820 static void vti6_dev_setup(struct net_device *dev) 821 { 822 dev->netdev_ops = &vti6_netdev_ops; 823 dev->destructor = vti6_dev_free; 824 825 dev->type = ARPHRD_TUNNEL6; 826 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr); 827 dev->mtu = ETH_DATA_LEN; 828 dev->flags |= IFF_NOARP; 829 dev->addr_len = sizeof(struct in6_addr); 830 netif_keep_dst(dev); 831 } 832 833 /** 834 * vti6_dev_init_gen - general initializer for all tunnel devices 835 * @dev: virtual device associated with tunnel 836 **/ 837 static inline int vti6_dev_init_gen(struct net_device *dev) 838 { 839 struct ip6_tnl *t = netdev_priv(dev); 840 841 t->dev = dev; 842 t->net = dev_net(dev); 843 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 844 if (!dev->tstats) 845 return -ENOMEM; 846 return 0; 847 } 848 849 /** 850 * vti6_dev_init - initializer for all non fallback tunnel devices 851 * @dev: virtual device associated with tunnel 852 **/ 853 static int vti6_dev_init(struct net_device *dev) 854 { 855 struct ip6_tnl *t = netdev_priv(dev); 856 int err = vti6_dev_init_gen(dev); 857 858 if (err) 859 return err; 860 vti6_link_config(t); 861 return 0; 862 } 863 864 /** 865 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device 866 * @dev: fallback device 867 * 868 * Return: 0 869 **/ 870 static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev) 871 { 872 struct ip6_tnl *t = netdev_priv(dev); 873 struct net *net = dev_net(dev); 874 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 875 876 t->parms.proto = IPPROTO_IPV6; 877 dev_hold(dev); 878 879 rcu_assign_pointer(ip6n->tnls_wc[0], t); 880 return 0; 881 } 882 883 static int vti6_validate(struct nlattr *tb[], struct nlattr *data[]) 884 { 885 return 0; 886 } 887 888 static void vti6_netlink_parms(struct nlattr *data[], 889 struct __ip6_tnl_parm *parms) 890 { 891 memset(parms, 0, sizeof(*parms)); 892 893 if (!data) 894 return; 895 896 if (data[IFLA_VTI_LINK]) 897 parms->link = nla_get_u32(data[IFLA_VTI_LINK]); 898 899 if (data[IFLA_VTI_LOCAL]) 900 nla_memcpy(&parms->laddr, data[IFLA_VTI_LOCAL], 901 sizeof(struct in6_addr)); 902 903 if (data[IFLA_VTI_REMOTE]) 904 nla_memcpy(&parms->raddr, data[IFLA_VTI_REMOTE], 905 sizeof(struct in6_addr)); 906 907 if (data[IFLA_VTI_IKEY]) 908 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]); 909 910 if (data[IFLA_VTI_OKEY]) 911 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]); 912 } 913 914 static int vti6_newlink(struct net *src_net, struct net_device *dev, 915 struct nlattr *tb[], struct nlattr *data[]) 916 { 917 struct net *net = dev_net(dev); 918 struct ip6_tnl *nt; 919 920 nt = netdev_priv(dev); 921 vti6_netlink_parms(data, &nt->parms); 922 923 nt->parms.proto = IPPROTO_IPV6; 924 925 if (vti6_locate(net, &nt->parms, 0)) 926 return -EEXIST; 927 928 return vti6_tnl_create2(dev); 929 } 930 931 static void vti6_dellink(struct net_device *dev, struct list_head *head) 932 { 933 struct net *net = dev_net(dev); 934 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 935 936 if (dev != ip6n->fb_tnl_dev) 937 unregister_netdevice_queue(dev, head); 938 } 939 940 static int vti6_changelink(struct net_device *dev, struct nlattr *tb[], 941 struct nlattr *data[]) 942 { 943 struct ip6_tnl *t; 944 struct __ip6_tnl_parm p; 945 struct net *net = dev_net(dev); 946 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 947 948 if (dev == ip6n->fb_tnl_dev) 949 return -EINVAL; 950 951 vti6_netlink_parms(data, &p); 952 953 t = vti6_locate(net, &p, 0); 954 955 if (t) { 956 if (t->dev != dev) 957 return -EEXIST; 958 } else 959 t = netdev_priv(dev); 960 961 return vti6_update(t, &p); 962 } 963 964 static size_t vti6_get_size(const struct net_device *dev) 965 { 966 return 967 /* IFLA_VTI_LINK */ 968 nla_total_size(4) + 969 /* IFLA_VTI_LOCAL */ 970 nla_total_size(sizeof(struct in6_addr)) + 971 /* IFLA_VTI_REMOTE */ 972 nla_total_size(sizeof(struct in6_addr)) + 973 /* IFLA_VTI_IKEY */ 974 nla_total_size(4) + 975 /* IFLA_VTI_OKEY */ 976 nla_total_size(4) + 977 0; 978 } 979 980 static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev) 981 { 982 struct ip6_tnl *tunnel = netdev_priv(dev); 983 struct __ip6_tnl_parm *parm = &tunnel->parms; 984 985 if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) || 986 nla_put(skb, IFLA_VTI_LOCAL, sizeof(struct in6_addr), 987 &parm->laddr) || 988 nla_put(skb, IFLA_VTI_REMOTE, sizeof(struct in6_addr), 989 &parm->raddr) || 990 nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) || 991 nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key)) 992 goto nla_put_failure; 993 return 0; 994 995 nla_put_failure: 996 return -EMSGSIZE; 997 } 998 999 static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = { 1000 [IFLA_VTI_LINK] = { .type = NLA_U32 }, 1001 [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) }, 1002 [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) }, 1003 [IFLA_VTI_IKEY] = { .type = NLA_U32 }, 1004 [IFLA_VTI_OKEY] = { .type = NLA_U32 }, 1005 }; 1006 1007 static struct rtnl_link_ops vti6_link_ops __read_mostly = { 1008 .kind = "vti6", 1009 .maxtype = IFLA_VTI_MAX, 1010 .policy = vti6_policy, 1011 .priv_size = sizeof(struct ip6_tnl), 1012 .setup = vti6_dev_setup, 1013 .validate = vti6_validate, 1014 .newlink = vti6_newlink, 1015 .dellink = vti6_dellink, 1016 .changelink = vti6_changelink, 1017 .get_size = vti6_get_size, 1018 .fill_info = vti6_fill_info, 1019 }; 1020 1021 static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n) 1022 { 1023 int h; 1024 struct ip6_tnl *t; 1025 LIST_HEAD(list); 1026 1027 for (h = 0; h < HASH_SIZE; h++) { 1028 t = rtnl_dereference(ip6n->tnls_r_l[h]); 1029 while (t != NULL) { 1030 unregister_netdevice_queue(t->dev, &list); 1031 t = rtnl_dereference(t->next); 1032 } 1033 } 1034 1035 t = rtnl_dereference(ip6n->tnls_wc[0]); 1036 unregister_netdevice_queue(t->dev, &list); 1037 unregister_netdevice_many(&list); 1038 } 1039 1040 static int __net_init vti6_init_net(struct net *net) 1041 { 1042 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 1043 struct ip6_tnl *t = NULL; 1044 int err; 1045 1046 ip6n->tnls[0] = ip6n->tnls_wc; 1047 ip6n->tnls[1] = ip6n->tnls_r_l; 1048 1049 err = -ENOMEM; 1050 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0", 1051 NET_NAME_UNKNOWN, vti6_dev_setup); 1052 1053 if (!ip6n->fb_tnl_dev) 1054 goto err_alloc_dev; 1055 dev_net_set(ip6n->fb_tnl_dev, net); 1056 ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops; 1057 1058 err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 1059 if (err < 0) 1060 goto err_register; 1061 1062 err = register_netdev(ip6n->fb_tnl_dev); 1063 if (err < 0) 1064 goto err_register; 1065 1066 t = netdev_priv(ip6n->fb_tnl_dev); 1067 1068 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 1069 return 0; 1070 1071 err_register: 1072 vti6_dev_free(ip6n->fb_tnl_dev); 1073 err_alloc_dev: 1074 return err; 1075 } 1076 1077 static void __net_exit vti6_exit_net(struct net *net) 1078 { 1079 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 1080 1081 rtnl_lock(); 1082 vti6_destroy_tunnels(ip6n); 1083 rtnl_unlock(); 1084 } 1085 1086 static struct pernet_operations vti6_net_ops = { 1087 .init = vti6_init_net, 1088 .exit = vti6_exit_net, 1089 .id = &vti6_net_id, 1090 .size = sizeof(struct vti6_net), 1091 }; 1092 1093 static struct xfrm6_protocol vti_esp6_protocol __read_mostly = { 1094 .handler = vti6_rcv, 1095 .cb_handler = vti6_rcv_cb, 1096 .err_handler = vti6_err, 1097 .priority = 100, 1098 }; 1099 1100 static struct xfrm6_protocol vti_ah6_protocol __read_mostly = { 1101 .handler = vti6_rcv, 1102 .cb_handler = vti6_rcv_cb, 1103 .err_handler = vti6_err, 1104 .priority = 100, 1105 }; 1106 1107 static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = { 1108 .handler = vti6_rcv, 1109 .cb_handler = vti6_rcv_cb, 1110 .err_handler = vti6_err, 1111 .priority = 100, 1112 }; 1113 1114 /** 1115 * vti6_tunnel_init - register protocol and reserve needed resources 1116 * 1117 * Return: 0 on success 1118 **/ 1119 static int __init vti6_tunnel_init(void) 1120 { 1121 const char *msg; 1122 int err; 1123 1124 msg = "tunnel device"; 1125 err = register_pernet_device(&vti6_net_ops); 1126 if (err < 0) 1127 goto pernet_dev_failed; 1128 1129 msg = "tunnel protocols"; 1130 err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP); 1131 if (err < 0) 1132 goto xfrm_proto_esp_failed; 1133 err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH); 1134 if (err < 0) 1135 goto xfrm_proto_ah_failed; 1136 err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP); 1137 if (err < 0) 1138 goto xfrm_proto_comp_failed; 1139 1140 msg = "netlink interface"; 1141 err = rtnl_link_register(&vti6_link_ops); 1142 if (err < 0) 1143 goto rtnl_link_failed; 1144 1145 return 0; 1146 1147 rtnl_link_failed: 1148 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); 1149 xfrm_proto_comp_failed: 1150 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); 1151 xfrm_proto_ah_failed: 1152 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); 1153 xfrm_proto_esp_failed: 1154 unregister_pernet_device(&vti6_net_ops); 1155 pernet_dev_failed: 1156 pr_err("vti6 init: failed to register %s\n", msg); 1157 return err; 1158 } 1159 1160 /** 1161 * vti6_tunnel_cleanup - free resources and unregister protocol 1162 **/ 1163 static void __exit vti6_tunnel_cleanup(void) 1164 { 1165 rtnl_link_unregister(&vti6_link_ops); 1166 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); 1167 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); 1168 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); 1169 unregister_pernet_device(&vti6_net_ops); 1170 } 1171 1172 module_init(vti6_tunnel_init); 1173 module_exit(vti6_tunnel_cleanup); 1174 MODULE_LICENSE("GPL"); 1175 MODULE_ALIAS_RTNL_LINK("vti6"); 1176 MODULE_ALIAS_NETDEV("ip6_vti0"); 1177 MODULE_AUTHOR("Steffen Klassert"); 1178 MODULE_DESCRIPTION("IPv6 virtual tunnel interface"); 1179