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) 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 vti6_net *ip6n = net_generic(t->net, vti6_net_id); 292 293 if (dev == ip6n->fb_tnl_dev) 294 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 295 else 296 vti6_tnl_unlink(ip6n, t); 297 dev_put(dev); 298 } 299 300 static int vti6_rcv(struct sk_buff *skb) 301 { 302 struct ip6_tnl *t; 303 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 304 305 rcu_read_lock(); 306 t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr); 307 if (t) { 308 if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) { 309 rcu_read_unlock(); 310 goto discard; 311 } 312 313 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 314 rcu_read_unlock(); 315 return 0; 316 } 317 318 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { 319 t->dev->stats.rx_dropped++; 320 rcu_read_unlock(); 321 goto discard; 322 } 323 324 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; 325 326 rcu_read_unlock(); 327 328 return xfrm6_rcv(skb); 329 } 330 rcu_read_unlock(); 331 return -EINVAL; 332 discard: 333 kfree_skb(skb); 334 return 0; 335 } 336 337 static int vti6_rcv_cb(struct sk_buff *skb, int err) 338 { 339 unsigned short family; 340 struct net_device *dev; 341 struct pcpu_sw_netstats *tstats; 342 struct xfrm_state *x; 343 struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6; 344 u32 orig_mark = skb->mark; 345 int ret; 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 skb->mark = be32_to_cpu(t->parms.i_key); 363 ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family); 364 skb->mark = orig_mark; 365 366 if (!ret) 367 return -EPERM; 368 369 skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev))); 370 skb->dev = dev; 371 372 tstats = this_cpu_ptr(dev->tstats); 373 u64_stats_update_begin(&tstats->syncp); 374 tstats->rx_packets++; 375 tstats->rx_bytes += skb->len; 376 u64_stats_update_end(&tstats->syncp); 377 378 return 0; 379 } 380 381 /** 382 * vti6_addr_conflict - compare packet addresses to tunnel's own 383 * @t: the outgoing tunnel device 384 * @hdr: IPv6 header from the incoming packet 385 * 386 * Description: 387 * Avoid trivial tunneling loop by checking that tunnel exit-point 388 * doesn't match source of incoming packet. 389 * 390 * Return: 391 * 1 if conflict, 392 * 0 else 393 **/ 394 static inline bool 395 vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 396 { 397 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 398 } 399 400 static bool vti6_state_check(const struct xfrm_state *x, 401 const struct in6_addr *dst, 402 const struct in6_addr *src) 403 { 404 xfrm_address_t *daddr = (xfrm_address_t *)dst; 405 xfrm_address_t *saddr = (xfrm_address_t *)src; 406 407 /* if there is no transform then this tunnel is not functional. 408 * Or if the xfrm is not mode tunnel. 409 */ 410 if (!x || x->props.mode != XFRM_MODE_TUNNEL || 411 x->props.family != AF_INET6) 412 return false; 413 414 if (ipv6_addr_any(dst)) 415 return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6); 416 417 if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6)) 418 return false; 419 420 return true; 421 } 422 423 /** 424 * vti6_xmit - send a packet 425 * @skb: the outgoing socket buffer 426 * @dev: the outgoing tunnel device 427 * @fl: the flow informations for the xfrm_lookup 428 **/ 429 static int 430 vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) 431 { 432 struct ip6_tnl *t = netdev_priv(dev); 433 struct net_device_stats *stats = &t->dev->stats; 434 struct dst_entry *dst = skb_dst(skb); 435 struct net_device *tdev; 436 struct xfrm_state *x; 437 int err = -1; 438 int mtu; 439 440 if (!dst) 441 goto tx_err_link_failure; 442 443 dst_hold(dst); 444 dst = xfrm_lookup(t->net, dst, fl, NULL, 0); 445 if (IS_ERR(dst)) { 446 err = PTR_ERR(dst); 447 dst = NULL; 448 goto tx_err_link_failure; 449 } 450 451 x = dst->xfrm; 452 if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr)) 453 goto tx_err_link_failure; 454 455 if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr, 456 (const struct in6_addr *)&x->id.daddr)) 457 goto tx_err_link_failure; 458 459 tdev = dst->dev; 460 461 if (tdev == dev) { 462 stats->collisions++; 463 net_warn_ratelimited("%s: Local routing loop detected!\n", 464 t->parms.name); 465 goto tx_err_dst_release; 466 } 467 468 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 469 skb_dst_set(skb, dst); 470 skb->dev = skb_dst(skb)->dev; 471 472 mtu = dst_mtu(dst); 473 if (!skb->ignore_df && skb->len > mtu) { 474 skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu); 475 476 if (skb->protocol == htons(ETH_P_IPV6)) 477 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 478 else 479 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 480 htonl(mtu)); 481 482 return -EMSGSIZE; 483 } 484 485 err = dst_output(t->net, skb->sk, skb); 486 if (net_xmit_eval(err) == 0) { 487 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats); 488 489 u64_stats_update_begin(&tstats->syncp); 490 tstats->tx_bytes += skb->len; 491 tstats->tx_packets++; 492 u64_stats_update_end(&tstats->syncp); 493 } else { 494 stats->tx_errors++; 495 stats->tx_aborted_errors++; 496 } 497 498 return 0; 499 tx_err_link_failure: 500 stats->tx_carrier_errors++; 501 dst_link_failure(skb); 502 tx_err_dst_release: 503 dst_release(dst); 504 return err; 505 } 506 507 static netdev_tx_t 508 vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 509 { 510 struct ip6_tnl *t = netdev_priv(dev); 511 struct net_device_stats *stats = &t->dev->stats; 512 struct ipv6hdr *ipv6h; 513 struct flowi fl; 514 int ret; 515 516 memset(&fl, 0, sizeof(fl)); 517 518 switch (skb->protocol) { 519 case htons(ETH_P_IPV6): 520 ipv6h = ipv6_hdr(skb); 521 522 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 523 vti6_addr_conflict(t, ipv6h)) 524 goto tx_err; 525 526 xfrm_decode_session(skb, &fl, AF_INET6); 527 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); 528 break; 529 case htons(ETH_P_IP): 530 xfrm_decode_session(skb, &fl, AF_INET); 531 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 532 break; 533 default: 534 goto tx_err; 535 } 536 537 /* override mark with tunnel output key */ 538 fl.flowi_mark = be32_to_cpu(t->parms.o_key); 539 540 ret = vti6_xmit(skb, dev, &fl); 541 if (ret < 0) 542 goto tx_err; 543 544 return NETDEV_TX_OK; 545 546 tx_err: 547 stats->tx_errors++; 548 stats->tx_dropped++; 549 kfree_skb(skb); 550 return NETDEV_TX_OK; 551 } 552 553 static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 554 u8 type, u8 code, int offset, __be32 info) 555 { 556 __be32 spi; 557 __u32 mark; 558 struct xfrm_state *x; 559 struct ip6_tnl *t; 560 struct ip_esp_hdr *esph; 561 struct ip_auth_hdr *ah; 562 struct ip_comp_hdr *ipch; 563 struct net *net = dev_net(skb->dev); 564 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 565 int protocol = iph->nexthdr; 566 567 t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr); 568 if (!t) 569 return -1; 570 571 mark = be32_to_cpu(t->parms.o_key); 572 573 switch (protocol) { 574 case IPPROTO_ESP: 575 esph = (struct ip_esp_hdr *)(skb->data + offset); 576 spi = esph->spi; 577 break; 578 case IPPROTO_AH: 579 ah = (struct ip_auth_hdr *)(skb->data + offset); 580 spi = ah->spi; 581 break; 582 case IPPROTO_COMP: 583 ipch = (struct ip_comp_hdr *)(skb->data + offset); 584 spi = htonl(ntohs(ipch->cpi)); 585 break; 586 default: 587 return 0; 588 } 589 590 if (type != ICMPV6_PKT_TOOBIG && 591 type != NDISC_REDIRECT) 592 return 0; 593 594 x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr, 595 spi, protocol, AF_INET6); 596 if (!x) 597 return 0; 598 599 if (type == NDISC_REDIRECT) 600 ip6_redirect(skb, net, skb->dev->ifindex, 0); 601 else 602 ip6_update_pmtu(skb, net, info, 0, 0); 603 xfrm_state_put(x); 604 605 return 0; 606 } 607 608 static void vti6_link_config(struct ip6_tnl *t) 609 { 610 struct net_device *dev = t->dev; 611 struct __ip6_tnl_parm *p = &t->parms; 612 613 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 614 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 615 616 p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV | 617 IP6_TNL_F_CAP_PER_PACKET); 618 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 619 620 if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV) 621 dev->flags |= IFF_POINTOPOINT; 622 else 623 dev->flags &= ~IFF_POINTOPOINT; 624 } 625 626 /** 627 * vti6_tnl_change - update the tunnel parameters 628 * @t: tunnel to be changed 629 * @p: tunnel configuration parameters 630 * 631 * Description: 632 * vti6_tnl_change() updates the tunnel parameters 633 **/ 634 static int 635 vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) 636 { 637 t->parms.laddr = p->laddr; 638 t->parms.raddr = p->raddr; 639 t->parms.link = p->link; 640 t->parms.i_key = p->i_key; 641 t->parms.o_key = p->o_key; 642 t->parms.proto = p->proto; 643 dst_cache_reset(&t->dst_cache); 644 vti6_link_config(t); 645 return 0; 646 } 647 648 static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) 649 { 650 struct net *net = dev_net(t->dev); 651 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 652 int err; 653 654 vti6_tnl_unlink(ip6n, t); 655 synchronize_net(); 656 err = vti6_tnl_change(t, p); 657 vti6_tnl_link(ip6n, t); 658 netdev_state_change(t->dev); 659 return err; 660 } 661 662 static void 663 vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u) 664 { 665 p->laddr = u->laddr; 666 p->raddr = u->raddr; 667 p->link = u->link; 668 p->i_key = u->i_key; 669 p->o_key = u->o_key; 670 p->proto = u->proto; 671 672 memcpy(p->name, u->name, sizeof(u->name)); 673 } 674 675 static void 676 vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p) 677 { 678 u->laddr = p->laddr; 679 u->raddr = p->raddr; 680 u->link = p->link; 681 u->i_key = p->i_key; 682 u->o_key = p->o_key; 683 u->proto = p->proto; 684 685 memcpy(u->name, p->name, sizeof(u->name)); 686 } 687 688 /** 689 * vti6_tnl_ioctl - configure vti6 tunnels from userspace 690 * @dev: virtual device associated with tunnel 691 * @ifr: parameters passed from userspace 692 * @cmd: command to be performed 693 * 694 * Description: 695 * vti6_ioctl() is used for managing vti6 tunnels 696 * from userspace. 697 * 698 * The possible commands are the following: 699 * %SIOCGETTUNNEL: get tunnel parameters for device 700 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 701 * %SIOCCHGTUNNEL: change tunnel parameters to those given 702 * %SIOCDELTUNNEL: delete tunnel 703 * 704 * The fallback device "ip6_vti0", created during module 705 * initialization, can be used for creating other tunnel devices. 706 * 707 * Return: 708 * 0 on success, 709 * %-EFAULT if unable to copy data to or from userspace, 710 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 711 * %-EINVAL if passed tunnel parameters are invalid, 712 * %-EEXIST if changing a tunnel's parameters would cause a conflict 713 * %-ENODEV if attempting to change or delete a nonexisting device 714 **/ 715 static int 716 vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 717 { 718 int err = 0; 719 struct ip6_tnl_parm2 p; 720 struct __ip6_tnl_parm p1; 721 struct ip6_tnl *t = NULL; 722 struct net *net = dev_net(dev); 723 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 724 725 switch (cmd) { 726 case SIOCGETTUNNEL: 727 if (dev == ip6n->fb_tnl_dev) { 728 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 729 err = -EFAULT; 730 break; 731 } 732 vti6_parm_from_user(&p1, &p); 733 t = vti6_locate(net, &p1, 0); 734 } else { 735 memset(&p, 0, sizeof(p)); 736 } 737 if (!t) 738 t = netdev_priv(dev); 739 vti6_parm_to_user(&p, &t->parms); 740 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 741 err = -EFAULT; 742 break; 743 case SIOCADDTUNNEL: 744 case SIOCCHGTUNNEL: 745 err = -EPERM; 746 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 747 break; 748 err = -EFAULT; 749 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 750 break; 751 err = -EINVAL; 752 if (p.proto != IPPROTO_IPV6 && p.proto != 0) 753 break; 754 vti6_parm_from_user(&p1, &p); 755 t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL); 756 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 757 if (t) { 758 if (t->dev != dev) { 759 err = -EEXIST; 760 break; 761 } 762 } else 763 t = netdev_priv(dev); 764 765 err = vti6_update(t, &p1); 766 } 767 if (t) { 768 err = 0; 769 vti6_parm_to_user(&p, &t->parms); 770 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 771 err = -EFAULT; 772 773 } else 774 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 775 break; 776 case SIOCDELTUNNEL: 777 err = -EPERM; 778 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 779 break; 780 781 if (dev == ip6n->fb_tnl_dev) { 782 err = -EFAULT; 783 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 784 break; 785 err = -ENOENT; 786 vti6_parm_from_user(&p1, &p); 787 t = vti6_locate(net, &p1, 0); 788 if (!t) 789 break; 790 err = -EPERM; 791 if (t->dev == ip6n->fb_tnl_dev) 792 break; 793 dev = t->dev; 794 } 795 err = 0; 796 unregister_netdevice(dev); 797 break; 798 default: 799 err = -EINVAL; 800 } 801 return err; 802 } 803 804 /** 805 * vti6_tnl_change_mtu - change mtu manually for tunnel device 806 * @dev: virtual device associated with tunnel 807 * @new_mtu: the new mtu 808 * 809 * Return: 810 * 0 on success, 811 * %-EINVAL if mtu too small 812 **/ 813 static int vti6_change_mtu(struct net_device *dev, int new_mtu) 814 { 815 if (new_mtu < IPV6_MIN_MTU) 816 return -EINVAL; 817 818 dev->mtu = new_mtu; 819 return 0; 820 } 821 822 static const struct net_device_ops vti6_netdev_ops = { 823 .ndo_init = vti6_dev_init, 824 .ndo_uninit = vti6_dev_uninit, 825 .ndo_start_xmit = vti6_tnl_xmit, 826 .ndo_do_ioctl = vti6_ioctl, 827 .ndo_change_mtu = vti6_change_mtu, 828 .ndo_get_stats64 = ip_tunnel_get_stats64, 829 .ndo_get_iflink = ip6_tnl_get_iflink, 830 }; 831 832 /** 833 * vti6_dev_setup - setup virtual tunnel device 834 * @dev: virtual device associated with tunnel 835 * 836 * Description: 837 * Initialize function pointers and device parameters 838 **/ 839 static void vti6_dev_setup(struct net_device *dev) 840 { 841 dev->netdev_ops = &vti6_netdev_ops; 842 dev->destructor = vti6_dev_free; 843 844 dev->type = ARPHRD_TUNNEL6; 845 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr); 846 dev->mtu = ETH_DATA_LEN; 847 dev->flags |= IFF_NOARP; 848 dev->addr_len = sizeof(struct in6_addr); 849 netif_keep_dst(dev); 850 } 851 852 /** 853 * vti6_dev_init_gen - general initializer for all tunnel devices 854 * @dev: virtual device associated with tunnel 855 **/ 856 static inline int vti6_dev_init_gen(struct net_device *dev) 857 { 858 struct ip6_tnl *t = netdev_priv(dev); 859 860 t->dev = dev; 861 t->net = dev_net(dev); 862 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 863 if (!dev->tstats) 864 return -ENOMEM; 865 return 0; 866 } 867 868 /** 869 * vti6_dev_init - initializer for all non fallback tunnel devices 870 * @dev: virtual device associated with tunnel 871 **/ 872 static int vti6_dev_init(struct net_device *dev) 873 { 874 struct ip6_tnl *t = netdev_priv(dev); 875 int err = vti6_dev_init_gen(dev); 876 877 if (err) 878 return err; 879 vti6_link_config(t); 880 return 0; 881 } 882 883 /** 884 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device 885 * @dev: fallback device 886 * 887 * Return: 0 888 **/ 889 static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev) 890 { 891 struct ip6_tnl *t = netdev_priv(dev); 892 struct net *net = dev_net(dev); 893 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 894 895 t->parms.proto = IPPROTO_IPV6; 896 dev_hold(dev); 897 898 rcu_assign_pointer(ip6n->tnls_wc[0], t); 899 return 0; 900 } 901 902 static int vti6_validate(struct nlattr *tb[], struct nlattr *data[]) 903 { 904 return 0; 905 } 906 907 static void vti6_netlink_parms(struct nlattr *data[], 908 struct __ip6_tnl_parm *parms) 909 { 910 memset(parms, 0, sizeof(*parms)); 911 912 if (!data) 913 return; 914 915 if (data[IFLA_VTI_LINK]) 916 parms->link = nla_get_u32(data[IFLA_VTI_LINK]); 917 918 if (data[IFLA_VTI_LOCAL]) 919 parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]); 920 921 if (data[IFLA_VTI_REMOTE]) 922 parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]); 923 924 if (data[IFLA_VTI_IKEY]) 925 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]); 926 927 if (data[IFLA_VTI_OKEY]) 928 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]); 929 } 930 931 static int vti6_newlink(struct net *src_net, struct net_device *dev, 932 struct nlattr *tb[], struct nlattr *data[]) 933 { 934 struct net *net = dev_net(dev); 935 struct ip6_tnl *nt; 936 937 nt = netdev_priv(dev); 938 vti6_netlink_parms(data, &nt->parms); 939 940 nt->parms.proto = IPPROTO_IPV6; 941 942 if (vti6_locate(net, &nt->parms, 0)) 943 return -EEXIST; 944 945 return vti6_tnl_create2(dev); 946 } 947 948 static void vti6_dellink(struct net_device *dev, struct list_head *head) 949 { 950 struct net *net = dev_net(dev); 951 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 952 953 if (dev != ip6n->fb_tnl_dev) 954 unregister_netdevice_queue(dev, head); 955 } 956 957 static int vti6_changelink(struct net_device *dev, struct nlattr *tb[], 958 struct nlattr *data[]) 959 { 960 struct ip6_tnl *t; 961 struct __ip6_tnl_parm p; 962 struct net *net = dev_net(dev); 963 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 964 965 if (dev == ip6n->fb_tnl_dev) 966 return -EINVAL; 967 968 vti6_netlink_parms(data, &p); 969 970 t = vti6_locate(net, &p, 0); 971 972 if (t) { 973 if (t->dev != dev) 974 return -EEXIST; 975 } else 976 t = netdev_priv(dev); 977 978 return vti6_update(t, &p); 979 } 980 981 static size_t vti6_get_size(const struct net_device *dev) 982 { 983 return 984 /* IFLA_VTI_LINK */ 985 nla_total_size(4) + 986 /* IFLA_VTI_LOCAL */ 987 nla_total_size(sizeof(struct in6_addr)) + 988 /* IFLA_VTI_REMOTE */ 989 nla_total_size(sizeof(struct in6_addr)) + 990 /* IFLA_VTI_IKEY */ 991 nla_total_size(4) + 992 /* IFLA_VTI_OKEY */ 993 nla_total_size(4) + 994 0; 995 } 996 997 static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev) 998 { 999 struct ip6_tnl *tunnel = netdev_priv(dev); 1000 struct __ip6_tnl_parm *parm = &tunnel->parms; 1001 1002 if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) || 1003 nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) || 1004 nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) || 1005 nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) || 1006 nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key)) 1007 goto nla_put_failure; 1008 return 0; 1009 1010 nla_put_failure: 1011 return -EMSGSIZE; 1012 } 1013 1014 static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = { 1015 [IFLA_VTI_LINK] = { .type = NLA_U32 }, 1016 [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) }, 1017 [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) }, 1018 [IFLA_VTI_IKEY] = { .type = NLA_U32 }, 1019 [IFLA_VTI_OKEY] = { .type = NLA_U32 }, 1020 }; 1021 1022 static struct rtnl_link_ops vti6_link_ops __read_mostly = { 1023 .kind = "vti6", 1024 .maxtype = IFLA_VTI_MAX, 1025 .policy = vti6_policy, 1026 .priv_size = sizeof(struct ip6_tnl), 1027 .setup = vti6_dev_setup, 1028 .validate = vti6_validate, 1029 .newlink = vti6_newlink, 1030 .dellink = vti6_dellink, 1031 .changelink = vti6_changelink, 1032 .get_size = vti6_get_size, 1033 .fill_info = vti6_fill_info, 1034 .get_link_net = ip6_tnl_get_link_net, 1035 }; 1036 1037 static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n) 1038 { 1039 int h; 1040 struct ip6_tnl *t; 1041 LIST_HEAD(list); 1042 1043 for (h = 0; h < HASH_SIZE; h++) { 1044 t = rtnl_dereference(ip6n->tnls_r_l[h]); 1045 while (t) { 1046 unregister_netdevice_queue(t->dev, &list); 1047 t = rtnl_dereference(t->next); 1048 } 1049 } 1050 1051 t = rtnl_dereference(ip6n->tnls_wc[0]); 1052 unregister_netdevice_queue(t->dev, &list); 1053 unregister_netdevice_many(&list); 1054 } 1055 1056 static int __net_init vti6_init_net(struct net *net) 1057 { 1058 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 1059 struct ip6_tnl *t = NULL; 1060 int err; 1061 1062 ip6n->tnls[0] = ip6n->tnls_wc; 1063 ip6n->tnls[1] = ip6n->tnls_r_l; 1064 1065 err = -ENOMEM; 1066 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0", 1067 NET_NAME_UNKNOWN, vti6_dev_setup); 1068 1069 if (!ip6n->fb_tnl_dev) 1070 goto err_alloc_dev; 1071 dev_net_set(ip6n->fb_tnl_dev, net); 1072 ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops; 1073 1074 err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 1075 if (err < 0) 1076 goto err_register; 1077 1078 err = register_netdev(ip6n->fb_tnl_dev); 1079 if (err < 0) 1080 goto err_register; 1081 1082 t = netdev_priv(ip6n->fb_tnl_dev); 1083 1084 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 1085 return 0; 1086 1087 err_register: 1088 vti6_dev_free(ip6n->fb_tnl_dev); 1089 err_alloc_dev: 1090 return err; 1091 } 1092 1093 static void __net_exit vti6_exit_net(struct net *net) 1094 { 1095 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 1096 1097 rtnl_lock(); 1098 vti6_destroy_tunnels(ip6n); 1099 rtnl_unlock(); 1100 } 1101 1102 static struct pernet_operations vti6_net_ops = { 1103 .init = vti6_init_net, 1104 .exit = vti6_exit_net, 1105 .id = &vti6_net_id, 1106 .size = sizeof(struct vti6_net), 1107 }; 1108 1109 static struct xfrm6_protocol vti_esp6_protocol __read_mostly = { 1110 .handler = vti6_rcv, 1111 .cb_handler = vti6_rcv_cb, 1112 .err_handler = vti6_err, 1113 .priority = 100, 1114 }; 1115 1116 static struct xfrm6_protocol vti_ah6_protocol __read_mostly = { 1117 .handler = vti6_rcv, 1118 .cb_handler = vti6_rcv_cb, 1119 .err_handler = vti6_err, 1120 .priority = 100, 1121 }; 1122 1123 static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = { 1124 .handler = vti6_rcv, 1125 .cb_handler = vti6_rcv_cb, 1126 .err_handler = vti6_err, 1127 .priority = 100, 1128 }; 1129 1130 /** 1131 * vti6_tunnel_init - register protocol and reserve needed resources 1132 * 1133 * Return: 0 on success 1134 **/ 1135 static int __init vti6_tunnel_init(void) 1136 { 1137 const char *msg; 1138 int err; 1139 1140 msg = "tunnel device"; 1141 err = register_pernet_device(&vti6_net_ops); 1142 if (err < 0) 1143 goto pernet_dev_failed; 1144 1145 msg = "tunnel protocols"; 1146 err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP); 1147 if (err < 0) 1148 goto xfrm_proto_esp_failed; 1149 err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH); 1150 if (err < 0) 1151 goto xfrm_proto_ah_failed; 1152 err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP); 1153 if (err < 0) 1154 goto xfrm_proto_comp_failed; 1155 1156 msg = "netlink interface"; 1157 err = rtnl_link_register(&vti6_link_ops); 1158 if (err < 0) 1159 goto rtnl_link_failed; 1160 1161 return 0; 1162 1163 rtnl_link_failed: 1164 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); 1165 xfrm_proto_comp_failed: 1166 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); 1167 xfrm_proto_ah_failed: 1168 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); 1169 xfrm_proto_esp_failed: 1170 unregister_pernet_device(&vti6_net_ops); 1171 pernet_dev_failed: 1172 pr_err("vti6 init: failed to register %s\n", msg); 1173 return err; 1174 } 1175 1176 /** 1177 * vti6_tunnel_cleanup - free resources and unregister protocol 1178 **/ 1179 static void __exit vti6_tunnel_cleanup(void) 1180 { 1181 rtnl_link_unregister(&vti6_link_ops); 1182 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); 1183 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); 1184 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); 1185 unregister_pernet_device(&vti6_net_ops); 1186 } 1187 1188 module_init(vti6_tunnel_init); 1189 module_exit(vti6_tunnel_cleanup); 1190 MODULE_LICENSE("GPL"); 1191 MODULE_ALIAS_RTNL_LINK("vti6"); 1192 MODULE_ALIAS_NETDEV("ip6_vti0"); 1193 MODULE_AUTHOR("Steffen Klassert"); 1194 MODULE_DESCRIPTION("IPv6 virtual tunnel interface"); 1195