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 #include <linux/etherdevice.h> 53 54 #define IP6_VTI_HASH_SIZE_SHIFT 5 55 #define IP6_VTI_HASH_SIZE (1 << IP6_VTI_HASH_SIZE_SHIFT) 56 57 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) 58 { 59 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); 60 61 return hash_32(hash, IP6_VTI_HASH_SIZE_SHIFT); 62 } 63 64 static int vti6_dev_init(struct net_device *dev); 65 static void vti6_dev_setup(struct net_device *dev); 66 static struct rtnl_link_ops vti6_link_ops __read_mostly; 67 68 static unsigned int vti6_net_id __read_mostly; 69 struct vti6_net { 70 /* the vti6 tunnel fallback device */ 71 struct net_device *fb_tnl_dev; 72 /* lists for storing tunnels in use */ 73 struct ip6_tnl __rcu *tnls_r_l[IP6_VTI_HASH_SIZE]; 74 struct ip6_tnl __rcu *tnls_wc[1]; 75 struct ip6_tnl __rcu **tnls[2]; 76 }; 77 78 #define for_each_vti6_tunnel_rcu(start) \ 79 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 80 81 /** 82 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses 83 * @net: network namespace 84 * @remote: the address of the tunnel exit-point 85 * @local: the address of the tunnel entry-point 86 * 87 * Return: 88 * tunnel matching given end-points if found, 89 * else fallback tunnel if its device is up, 90 * else %NULL 91 **/ 92 static struct ip6_tnl * 93 vti6_tnl_lookup(struct net *net, const struct in6_addr *remote, 94 const struct in6_addr *local) 95 { 96 unsigned int hash = HASH(remote, local); 97 struct ip6_tnl *t; 98 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 99 struct in6_addr any; 100 101 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 102 if (ipv6_addr_equal(local, &t->parms.laddr) && 103 ipv6_addr_equal(remote, &t->parms.raddr) && 104 (t->dev->flags & IFF_UP)) 105 return t; 106 } 107 108 memset(&any, 0, sizeof(any)); 109 hash = HASH(&any, local); 110 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 111 if (ipv6_addr_equal(local, &t->parms.laddr) && 112 (t->dev->flags & IFF_UP)) 113 return t; 114 } 115 116 hash = HASH(remote, &any); 117 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { 118 if (ipv6_addr_equal(remote, &t->parms.raddr) && 119 (t->dev->flags & IFF_UP)) 120 return t; 121 } 122 123 t = rcu_dereference(ip6n->tnls_wc[0]); 124 if (t && (t->dev->flags & IFF_UP)) 125 return t; 126 127 return NULL; 128 } 129 130 /** 131 * vti6_tnl_bucket - get head of list matching given tunnel parameters 132 * @p: parameters containing tunnel end-points 133 * 134 * Description: 135 * vti6_tnl_bucket() returns the head of the list matching the 136 * &struct in6_addr entries laddr and raddr in @p. 137 * 138 * Return: head of IPv6 tunnel list 139 **/ 140 static struct ip6_tnl __rcu ** 141 vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p) 142 { 143 const struct in6_addr *remote = &p->raddr; 144 const struct in6_addr *local = &p->laddr; 145 unsigned int h = 0; 146 int prio = 0; 147 148 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { 149 prio = 1; 150 h = HASH(remote, local); 151 } 152 return &ip6n->tnls[prio][h]; 153 } 154 155 static void 156 vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t) 157 { 158 struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms); 159 160 rcu_assign_pointer(t->next , rtnl_dereference(*tp)); 161 rcu_assign_pointer(*tp, t); 162 } 163 164 static void 165 vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t) 166 { 167 struct ip6_tnl __rcu **tp; 168 struct ip6_tnl *iter; 169 170 for (tp = vti6_tnl_bucket(ip6n, &t->parms); 171 (iter = rtnl_dereference(*tp)) != NULL; 172 tp = &iter->next) { 173 if (t == iter) { 174 rcu_assign_pointer(*tp, t->next); 175 break; 176 } 177 } 178 } 179 180 static void vti6_dev_free(struct net_device *dev) 181 { 182 free_percpu(dev->tstats); 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 dev->rtnl_link_ops = &vti6_link_ops; 193 err = register_netdevice(dev); 194 if (err < 0) 195 goto out; 196 197 strcpy(t->parms.name, dev->name); 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 if (!dev_valid_name(p->name)) 217 goto failed; 218 strlcpy(name, p->name, IFNAMSIZ); 219 } else { 220 sprintf(name, "ip6_vti%%d"); 221 } 222 223 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup); 224 if (!dev) 225 goto failed; 226 227 dev_net_set(dev, net); 228 229 t = netdev_priv(dev); 230 t->parms = *p; 231 t->net = dev_net(dev); 232 233 err = vti6_tnl_create2(dev); 234 if (err < 0) 235 goto failed_free; 236 237 return t; 238 239 failed_free: 240 free_netdev(dev); 241 failed: 242 return NULL; 243 } 244 245 /** 246 * vti6_locate - find or create tunnel matching given parameters 247 * @net: network namespace 248 * @p: tunnel parameters 249 * @create: != 0 if allowed to create new tunnel if no match found 250 * 251 * Description: 252 * vti6_locate() first tries to locate an existing tunnel 253 * based on @parms. If this is unsuccessful, but @create is set a new 254 * tunnel device is created and registered for use. 255 * 256 * Return: 257 * matching tunnel or NULL 258 **/ 259 static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p, 260 int create) 261 { 262 const struct in6_addr *remote = &p->raddr; 263 const struct in6_addr *local = &p->laddr; 264 struct ip6_tnl __rcu **tp; 265 struct ip6_tnl *t; 266 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 267 268 for (tp = vti6_tnl_bucket(ip6n, p); 269 (t = rtnl_dereference(*tp)) != NULL; 270 tp = &t->next) { 271 if (ipv6_addr_equal(local, &t->parms.laddr) && 272 ipv6_addr_equal(remote, &t->parms.raddr)) { 273 if (create) 274 return NULL; 275 276 return t; 277 } 278 } 279 if (!create) 280 return NULL; 281 return vti6_tnl_create(net, p); 282 } 283 284 /** 285 * vti6_dev_uninit - tunnel device uninitializer 286 * @dev: the device to be destroyed 287 * 288 * Description: 289 * vti6_dev_uninit() removes tunnel from its list 290 **/ 291 static void vti6_dev_uninit(struct net_device *dev) 292 { 293 struct ip6_tnl *t = netdev_priv(dev); 294 struct vti6_net *ip6n = net_generic(t->net, vti6_net_id); 295 296 if (dev == ip6n->fb_tnl_dev) 297 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); 298 else 299 vti6_tnl_unlink(ip6n, t); 300 dev_put(dev); 301 } 302 303 static int vti6_rcv(struct sk_buff *skb) 304 { 305 struct ip6_tnl *t; 306 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 307 308 rcu_read_lock(); 309 t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr); 310 if (t) { 311 if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) { 312 rcu_read_unlock(); 313 goto discard; 314 } 315 316 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { 317 rcu_read_unlock(); 318 return 0; 319 } 320 321 ipv6h = ipv6_hdr(skb); 322 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { 323 t->dev->stats.rx_dropped++; 324 rcu_read_unlock(); 325 goto discard; 326 } 327 328 rcu_read_unlock(); 329 330 return xfrm6_rcv_tnl(skb, t); 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 xfrm_mode *inner_mode; 346 struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6; 347 u32 orig_mark = skb->mark; 348 int ret; 349 350 if (!t) 351 return 1; 352 353 dev = t->dev; 354 355 if (err) { 356 dev->stats.rx_errors++; 357 dev->stats.rx_dropped++; 358 359 return 0; 360 } 361 362 x = xfrm_input_state(skb); 363 364 inner_mode = x->inner_mode; 365 366 if (x->sel.family == AF_UNSPEC) { 367 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); 368 if (inner_mode == NULL) { 369 XFRM_INC_STATS(dev_net(skb->dev), 370 LINUX_MIB_XFRMINSTATEMODEERROR); 371 return -EINVAL; 372 } 373 } 374 375 family = inner_mode->afinfo->family; 376 377 skb->mark = be32_to_cpu(t->parms.i_key); 378 ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family); 379 skb->mark = orig_mark; 380 381 if (!ret) 382 return -EPERM; 383 384 skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev))); 385 skb->dev = dev; 386 387 tstats = this_cpu_ptr(dev->tstats); 388 u64_stats_update_begin(&tstats->syncp); 389 tstats->rx_packets++; 390 tstats->rx_bytes += skb->len; 391 u64_stats_update_end(&tstats->syncp); 392 393 return 0; 394 } 395 396 /** 397 * vti6_addr_conflict - compare packet addresses to tunnel's own 398 * @t: the outgoing tunnel device 399 * @hdr: IPv6 header from the incoming packet 400 * 401 * Description: 402 * Avoid trivial tunneling loop by checking that tunnel exit-point 403 * doesn't match source of incoming packet. 404 * 405 * Return: 406 * 1 if conflict, 407 * 0 else 408 **/ 409 static inline bool 410 vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) 411 { 412 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 413 } 414 415 static bool vti6_state_check(const struct xfrm_state *x, 416 const struct in6_addr *dst, 417 const struct in6_addr *src) 418 { 419 xfrm_address_t *daddr = (xfrm_address_t *)dst; 420 xfrm_address_t *saddr = (xfrm_address_t *)src; 421 422 /* if there is no transform then this tunnel is not functional. 423 * Or if the xfrm is not mode tunnel. 424 */ 425 if (!x || x->props.mode != XFRM_MODE_TUNNEL || 426 x->props.family != AF_INET6) 427 return false; 428 429 if (ipv6_addr_any(dst)) 430 return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6); 431 432 if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6)) 433 return false; 434 435 return true; 436 } 437 438 /** 439 * vti6_xmit - send a packet 440 * @skb: the outgoing socket buffer 441 * @dev: the outgoing tunnel device 442 * @fl: the flow informations for the xfrm_lookup 443 **/ 444 static int 445 vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) 446 { 447 struct ip6_tnl *t = netdev_priv(dev); 448 struct net_device_stats *stats = &t->dev->stats; 449 struct dst_entry *dst = skb_dst(skb); 450 struct net_device *tdev; 451 struct xfrm_state *x; 452 int pkt_len = skb->len; 453 int err = -1; 454 int mtu; 455 456 if (!dst) 457 goto tx_err_link_failure; 458 459 dst_hold(dst); 460 dst = xfrm_lookup(t->net, dst, fl, NULL, 0); 461 if (IS_ERR(dst)) { 462 err = PTR_ERR(dst); 463 dst = NULL; 464 goto tx_err_link_failure; 465 } 466 467 x = dst->xfrm; 468 if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr)) 469 goto tx_err_link_failure; 470 471 if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr, 472 (const struct in6_addr *)&x->id.daddr)) 473 goto tx_err_link_failure; 474 475 tdev = dst->dev; 476 477 if (tdev == dev) { 478 stats->collisions++; 479 net_warn_ratelimited("%s: Local routing loop detected!\n", 480 t->parms.name); 481 goto tx_err_dst_release; 482 } 483 484 mtu = dst_mtu(dst); 485 if (skb->len > mtu) { 486 skb_dst_update_pmtu(skb, mtu); 487 488 if (skb->protocol == htons(ETH_P_IPV6)) { 489 if (mtu < IPV6_MIN_MTU) 490 mtu = IPV6_MIN_MTU; 491 492 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 493 } else { 494 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 495 htonl(mtu)); 496 } 497 498 err = -EMSGSIZE; 499 goto tx_err_dst_release; 500 } 501 502 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); 503 skb_dst_set(skb, dst); 504 skb->dev = skb_dst(skb)->dev; 505 506 err = dst_output(t->net, skb->sk, skb); 507 if (net_xmit_eval(err) == 0) 508 err = pkt_len; 509 iptunnel_xmit_stats(dev, err); 510 511 return 0; 512 tx_err_link_failure: 513 stats->tx_carrier_errors++; 514 dst_link_failure(skb); 515 tx_err_dst_release: 516 dst_release(dst); 517 return err; 518 } 519 520 static netdev_tx_t 521 vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) 522 { 523 struct ip6_tnl *t = netdev_priv(dev); 524 struct net_device_stats *stats = &t->dev->stats; 525 struct flowi fl; 526 int ret; 527 528 if (!pskb_inet_may_pull(skb)) 529 goto tx_err; 530 531 memset(&fl, 0, sizeof(fl)); 532 533 switch (skb->protocol) { 534 case htons(ETH_P_IPV6): 535 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || 536 vti6_addr_conflict(t, ipv6_hdr(skb))) 537 goto tx_err; 538 539 xfrm_decode_session(skb, &fl, AF_INET6); 540 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); 541 break; 542 case htons(ETH_P_IP): 543 xfrm_decode_session(skb, &fl, AF_INET); 544 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 545 break; 546 default: 547 goto tx_err; 548 } 549 550 /* override mark with tunnel output key */ 551 fl.flowi_mark = be32_to_cpu(t->parms.o_key); 552 553 ret = vti6_xmit(skb, dev, &fl); 554 if (ret < 0) 555 goto tx_err; 556 557 return NETDEV_TX_OK; 558 559 tx_err: 560 stats->tx_errors++; 561 stats->tx_dropped++; 562 kfree_skb(skb); 563 return NETDEV_TX_OK; 564 } 565 566 static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 567 u8 type, u8 code, int offset, __be32 info) 568 { 569 __be32 spi; 570 __u32 mark; 571 struct xfrm_state *x; 572 struct ip6_tnl *t; 573 struct ip_esp_hdr *esph; 574 struct ip_auth_hdr *ah; 575 struct ip_comp_hdr *ipch; 576 struct net *net = dev_net(skb->dev); 577 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 578 int protocol = iph->nexthdr; 579 580 t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr); 581 if (!t) 582 return -1; 583 584 mark = be32_to_cpu(t->parms.o_key); 585 586 switch (protocol) { 587 case IPPROTO_ESP: 588 esph = (struct ip_esp_hdr *)(skb->data + offset); 589 spi = esph->spi; 590 break; 591 case IPPROTO_AH: 592 ah = (struct ip_auth_hdr *)(skb->data + offset); 593 spi = ah->spi; 594 break; 595 case IPPROTO_COMP: 596 ipch = (struct ip_comp_hdr *)(skb->data + offset); 597 spi = htonl(ntohs(ipch->cpi)); 598 break; 599 default: 600 return 0; 601 } 602 603 if (type != ICMPV6_PKT_TOOBIG && 604 type != NDISC_REDIRECT) 605 return 0; 606 607 x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr, 608 spi, protocol, AF_INET6); 609 if (!x) 610 return 0; 611 612 if (type == NDISC_REDIRECT) 613 ip6_redirect(skb, net, skb->dev->ifindex, 0, 614 sock_net_uid(net, NULL)); 615 else 616 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 617 xfrm_state_put(x); 618 619 return 0; 620 } 621 622 static void vti6_link_config(struct ip6_tnl *t, bool keep_mtu) 623 { 624 struct net_device *dev = t->dev; 625 struct __ip6_tnl_parm *p = &t->parms; 626 struct net_device *tdev = NULL; 627 int mtu; 628 629 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 630 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 631 632 p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV | 633 IP6_TNL_F_CAP_PER_PACKET); 634 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 635 636 if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV) 637 dev->flags |= IFF_POINTOPOINT; 638 else 639 dev->flags &= ~IFF_POINTOPOINT; 640 641 if (keep_mtu && dev->mtu) { 642 dev->mtu = clamp(dev->mtu, dev->min_mtu, dev->max_mtu); 643 return; 644 } 645 646 if (p->flags & IP6_TNL_F_CAP_XMIT) { 647 int strict = (ipv6_addr_type(&p->raddr) & 648 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)); 649 struct rt6_info *rt = rt6_lookup(t->net, 650 &p->raddr, &p->laddr, 651 p->link, NULL, strict); 652 653 if (rt) 654 tdev = rt->dst.dev; 655 ip6_rt_put(rt); 656 } 657 658 if (!tdev && p->link) 659 tdev = __dev_get_by_index(t->net, p->link); 660 661 if (tdev) 662 mtu = tdev->mtu - sizeof(struct ipv6hdr); 663 else 664 mtu = ETH_DATA_LEN - LL_MAX_HEADER - sizeof(struct ipv6hdr); 665 666 dev->mtu = max_t(int, mtu, IPV4_MIN_MTU); 667 } 668 669 /** 670 * vti6_tnl_change - update the tunnel parameters 671 * @t: tunnel to be changed 672 * @p: tunnel configuration parameters 673 * @keep_mtu: MTU was set from userspace, don't re-compute it 674 * 675 * Description: 676 * vti6_tnl_change() updates the tunnel parameters 677 **/ 678 static int 679 vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p, 680 bool keep_mtu) 681 { 682 t->parms.laddr = p->laddr; 683 t->parms.raddr = p->raddr; 684 t->parms.link = p->link; 685 t->parms.i_key = p->i_key; 686 t->parms.o_key = p->o_key; 687 t->parms.proto = p->proto; 688 t->parms.fwmark = p->fwmark; 689 dst_cache_reset(&t->dst_cache); 690 vti6_link_config(t, keep_mtu); 691 return 0; 692 } 693 694 static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p, 695 bool keep_mtu) 696 { 697 struct net *net = dev_net(t->dev); 698 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 699 int err; 700 701 vti6_tnl_unlink(ip6n, t); 702 synchronize_net(); 703 err = vti6_tnl_change(t, p, keep_mtu); 704 vti6_tnl_link(ip6n, t); 705 netdev_state_change(t->dev); 706 return err; 707 } 708 709 static void 710 vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u) 711 { 712 p->laddr = u->laddr; 713 p->raddr = u->raddr; 714 p->link = u->link; 715 p->i_key = u->i_key; 716 p->o_key = u->o_key; 717 p->proto = u->proto; 718 719 memcpy(p->name, u->name, sizeof(u->name)); 720 } 721 722 static void 723 vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p) 724 { 725 u->laddr = p->laddr; 726 u->raddr = p->raddr; 727 u->link = p->link; 728 u->i_key = p->i_key; 729 u->o_key = p->o_key; 730 if (u->i_key) 731 u->i_flags |= GRE_KEY; 732 if (u->o_key) 733 u->o_flags |= GRE_KEY; 734 u->proto = p->proto; 735 736 memcpy(u->name, p->name, sizeof(u->name)); 737 } 738 739 /** 740 * vti6_ioctl - configure vti6 tunnels from userspace 741 * @dev: virtual device associated with tunnel 742 * @ifr: parameters passed from userspace 743 * @cmd: command to be performed 744 * 745 * Description: 746 * vti6_ioctl() is used for managing vti6 tunnels 747 * from userspace. 748 * 749 * The possible commands are the following: 750 * %SIOCGETTUNNEL: get tunnel parameters for device 751 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters 752 * %SIOCCHGTUNNEL: change tunnel parameters to those given 753 * %SIOCDELTUNNEL: delete tunnel 754 * 755 * The fallback device "ip6_vti0", created during module 756 * initialization, can be used for creating other tunnel devices. 757 * 758 * Return: 759 * 0 on success, 760 * %-EFAULT if unable to copy data to or from userspace, 761 * %-EPERM if current process hasn't %CAP_NET_ADMIN set 762 * %-EINVAL if passed tunnel parameters are invalid, 763 * %-EEXIST if changing a tunnel's parameters would cause a conflict 764 * %-ENODEV if attempting to change or delete a nonexisting device 765 **/ 766 static int 767 vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 768 { 769 int err = 0; 770 struct ip6_tnl_parm2 p; 771 struct __ip6_tnl_parm p1; 772 struct ip6_tnl *t = NULL; 773 struct net *net = dev_net(dev); 774 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 775 776 switch (cmd) { 777 case SIOCGETTUNNEL: 778 if (dev == ip6n->fb_tnl_dev) { 779 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 780 err = -EFAULT; 781 break; 782 } 783 vti6_parm_from_user(&p1, &p); 784 t = vti6_locate(net, &p1, 0); 785 } else { 786 memset(&p, 0, sizeof(p)); 787 } 788 if (!t) 789 t = netdev_priv(dev); 790 vti6_parm_to_user(&p, &t->parms); 791 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 792 err = -EFAULT; 793 break; 794 case SIOCADDTUNNEL: 795 case SIOCCHGTUNNEL: 796 err = -EPERM; 797 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 798 break; 799 err = -EFAULT; 800 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 801 break; 802 err = -EINVAL; 803 if (p.proto != IPPROTO_IPV6 && p.proto != 0) 804 break; 805 vti6_parm_from_user(&p1, &p); 806 t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL); 807 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { 808 if (t) { 809 if (t->dev != dev) { 810 err = -EEXIST; 811 break; 812 } 813 } else 814 t = netdev_priv(dev); 815 816 err = vti6_update(t, &p1, false); 817 } 818 if (t) { 819 err = 0; 820 vti6_parm_to_user(&p, &t->parms); 821 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 822 err = -EFAULT; 823 824 } else 825 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 826 break; 827 case SIOCDELTUNNEL: 828 err = -EPERM; 829 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 830 break; 831 832 if (dev == ip6n->fb_tnl_dev) { 833 err = -EFAULT; 834 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 835 break; 836 err = -ENOENT; 837 vti6_parm_from_user(&p1, &p); 838 t = vti6_locate(net, &p1, 0); 839 if (!t) 840 break; 841 err = -EPERM; 842 if (t->dev == ip6n->fb_tnl_dev) 843 break; 844 dev = t->dev; 845 } 846 err = 0; 847 unregister_netdevice(dev); 848 break; 849 default: 850 err = -EINVAL; 851 } 852 return err; 853 } 854 855 static const struct net_device_ops vti6_netdev_ops = { 856 .ndo_init = vti6_dev_init, 857 .ndo_uninit = vti6_dev_uninit, 858 .ndo_start_xmit = vti6_tnl_xmit, 859 .ndo_do_ioctl = vti6_ioctl, 860 .ndo_get_stats64 = ip_tunnel_get_stats64, 861 .ndo_get_iflink = ip6_tnl_get_iflink, 862 }; 863 864 /** 865 * vti6_dev_setup - setup virtual tunnel device 866 * @dev: virtual device associated with tunnel 867 * 868 * Description: 869 * Initialize function pointers and device parameters 870 **/ 871 static void vti6_dev_setup(struct net_device *dev) 872 { 873 dev->netdev_ops = &vti6_netdev_ops; 874 dev->needs_free_netdev = true; 875 dev->priv_destructor = vti6_dev_free; 876 877 dev->type = ARPHRD_TUNNEL6; 878 dev->min_mtu = IPV4_MIN_MTU; 879 dev->max_mtu = IP_MAX_MTU - sizeof(struct ipv6hdr); 880 dev->flags |= IFF_NOARP; 881 dev->addr_len = sizeof(struct in6_addr); 882 netif_keep_dst(dev); 883 /* This perm addr will be used as interface identifier by IPv6 */ 884 dev->addr_assign_type = NET_ADDR_RANDOM; 885 eth_random_addr(dev->perm_addr); 886 } 887 888 /** 889 * vti6_dev_init_gen - general initializer for all tunnel devices 890 * @dev: virtual device associated with tunnel 891 **/ 892 static inline int vti6_dev_init_gen(struct net_device *dev) 893 { 894 struct ip6_tnl *t = netdev_priv(dev); 895 896 t->dev = dev; 897 t->net = dev_net(dev); 898 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 899 if (!dev->tstats) 900 return -ENOMEM; 901 return 0; 902 } 903 904 /** 905 * vti6_dev_init - initializer for all non fallback tunnel devices 906 * @dev: virtual device associated with tunnel 907 **/ 908 static int vti6_dev_init(struct net_device *dev) 909 { 910 struct ip6_tnl *t = netdev_priv(dev); 911 int err = vti6_dev_init_gen(dev); 912 913 if (err) 914 return err; 915 vti6_link_config(t, true); 916 return 0; 917 } 918 919 /** 920 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device 921 * @dev: fallback device 922 * 923 * Return: 0 924 **/ 925 static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev) 926 { 927 struct ip6_tnl *t = netdev_priv(dev); 928 struct net *net = dev_net(dev); 929 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 930 931 t->parms.proto = IPPROTO_IPV6; 932 dev_hold(dev); 933 934 rcu_assign_pointer(ip6n->tnls_wc[0], t); 935 return 0; 936 } 937 938 static int vti6_validate(struct nlattr *tb[], struct nlattr *data[], 939 struct netlink_ext_ack *extack) 940 { 941 return 0; 942 } 943 944 static void vti6_netlink_parms(struct nlattr *data[], 945 struct __ip6_tnl_parm *parms) 946 { 947 memset(parms, 0, sizeof(*parms)); 948 949 if (!data) 950 return; 951 952 if (data[IFLA_VTI_LINK]) 953 parms->link = nla_get_u32(data[IFLA_VTI_LINK]); 954 955 if (data[IFLA_VTI_LOCAL]) 956 parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]); 957 958 if (data[IFLA_VTI_REMOTE]) 959 parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]); 960 961 if (data[IFLA_VTI_IKEY]) 962 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]); 963 964 if (data[IFLA_VTI_OKEY]) 965 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]); 966 967 if (data[IFLA_VTI_FWMARK]) 968 parms->fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]); 969 } 970 971 static int vti6_newlink(struct net *src_net, struct net_device *dev, 972 struct nlattr *tb[], struct nlattr *data[], 973 struct netlink_ext_ack *extack) 974 { 975 struct net *net = dev_net(dev); 976 struct ip6_tnl *nt; 977 978 nt = netdev_priv(dev); 979 vti6_netlink_parms(data, &nt->parms); 980 981 nt->parms.proto = IPPROTO_IPV6; 982 983 if (vti6_locate(net, &nt->parms, 0)) 984 return -EEXIST; 985 986 return vti6_tnl_create2(dev); 987 } 988 989 static void vti6_dellink(struct net_device *dev, struct list_head *head) 990 { 991 struct net *net = dev_net(dev); 992 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 993 994 if (dev != ip6n->fb_tnl_dev) 995 unregister_netdevice_queue(dev, head); 996 } 997 998 static int vti6_changelink(struct net_device *dev, struct nlattr *tb[], 999 struct nlattr *data[], 1000 struct netlink_ext_ack *extack) 1001 { 1002 struct ip6_tnl *t; 1003 struct __ip6_tnl_parm p; 1004 struct net *net = dev_net(dev); 1005 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 1006 1007 if (dev == ip6n->fb_tnl_dev) 1008 return -EINVAL; 1009 1010 vti6_netlink_parms(data, &p); 1011 1012 t = vti6_locate(net, &p, 0); 1013 1014 if (t) { 1015 if (t->dev != dev) 1016 return -EEXIST; 1017 } else 1018 t = netdev_priv(dev); 1019 1020 return vti6_update(t, &p, tb && tb[IFLA_MTU]); 1021 } 1022 1023 static size_t vti6_get_size(const struct net_device *dev) 1024 { 1025 return 1026 /* IFLA_VTI_LINK */ 1027 nla_total_size(4) + 1028 /* IFLA_VTI_LOCAL */ 1029 nla_total_size(sizeof(struct in6_addr)) + 1030 /* IFLA_VTI_REMOTE */ 1031 nla_total_size(sizeof(struct in6_addr)) + 1032 /* IFLA_VTI_IKEY */ 1033 nla_total_size(4) + 1034 /* IFLA_VTI_OKEY */ 1035 nla_total_size(4) + 1036 /* IFLA_VTI_FWMARK */ 1037 nla_total_size(4) + 1038 0; 1039 } 1040 1041 static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev) 1042 { 1043 struct ip6_tnl *tunnel = netdev_priv(dev); 1044 struct __ip6_tnl_parm *parm = &tunnel->parms; 1045 1046 if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) || 1047 nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) || 1048 nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) || 1049 nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) || 1050 nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key) || 1051 nla_put_u32(skb, IFLA_VTI_FWMARK, parm->fwmark)) 1052 goto nla_put_failure; 1053 return 0; 1054 1055 nla_put_failure: 1056 return -EMSGSIZE; 1057 } 1058 1059 static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = { 1060 [IFLA_VTI_LINK] = { .type = NLA_U32 }, 1061 [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) }, 1062 [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) }, 1063 [IFLA_VTI_IKEY] = { .type = NLA_U32 }, 1064 [IFLA_VTI_OKEY] = { .type = NLA_U32 }, 1065 [IFLA_VTI_FWMARK] = { .type = NLA_U32 }, 1066 }; 1067 1068 static struct rtnl_link_ops vti6_link_ops __read_mostly = { 1069 .kind = "vti6", 1070 .maxtype = IFLA_VTI_MAX, 1071 .policy = vti6_policy, 1072 .priv_size = sizeof(struct ip6_tnl), 1073 .setup = vti6_dev_setup, 1074 .validate = vti6_validate, 1075 .newlink = vti6_newlink, 1076 .dellink = vti6_dellink, 1077 .changelink = vti6_changelink, 1078 .get_size = vti6_get_size, 1079 .fill_info = vti6_fill_info, 1080 .get_link_net = ip6_tnl_get_link_net, 1081 }; 1082 1083 static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n, 1084 struct list_head *list) 1085 { 1086 int h; 1087 struct ip6_tnl *t; 1088 1089 for (h = 0; h < IP6_VTI_HASH_SIZE; h++) { 1090 t = rtnl_dereference(ip6n->tnls_r_l[h]); 1091 while (t) { 1092 unregister_netdevice_queue(t->dev, list); 1093 t = rtnl_dereference(t->next); 1094 } 1095 } 1096 1097 t = rtnl_dereference(ip6n->tnls_wc[0]); 1098 if (t) 1099 unregister_netdevice_queue(t->dev, list); 1100 } 1101 1102 static int __net_init vti6_init_net(struct net *net) 1103 { 1104 struct vti6_net *ip6n = net_generic(net, vti6_net_id); 1105 struct ip6_tnl *t = NULL; 1106 int err; 1107 1108 ip6n->tnls[0] = ip6n->tnls_wc; 1109 ip6n->tnls[1] = ip6n->tnls_r_l; 1110 1111 if (!net_has_fallback_tunnels(net)) 1112 return 0; 1113 err = -ENOMEM; 1114 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0", 1115 NET_NAME_UNKNOWN, vti6_dev_setup); 1116 1117 if (!ip6n->fb_tnl_dev) 1118 goto err_alloc_dev; 1119 dev_net_set(ip6n->fb_tnl_dev, net); 1120 ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops; 1121 1122 err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev); 1123 if (err < 0) 1124 goto err_register; 1125 1126 err = register_netdev(ip6n->fb_tnl_dev); 1127 if (err < 0) 1128 goto err_register; 1129 1130 t = netdev_priv(ip6n->fb_tnl_dev); 1131 1132 strcpy(t->parms.name, ip6n->fb_tnl_dev->name); 1133 return 0; 1134 1135 err_register: 1136 free_netdev(ip6n->fb_tnl_dev); 1137 err_alloc_dev: 1138 return err; 1139 } 1140 1141 static void __net_exit vti6_exit_batch_net(struct list_head *net_list) 1142 { 1143 struct vti6_net *ip6n; 1144 struct net *net; 1145 LIST_HEAD(list); 1146 1147 rtnl_lock(); 1148 list_for_each_entry(net, net_list, exit_list) { 1149 ip6n = net_generic(net, vti6_net_id); 1150 vti6_destroy_tunnels(ip6n, &list); 1151 } 1152 unregister_netdevice_many(&list); 1153 rtnl_unlock(); 1154 } 1155 1156 static struct pernet_operations vti6_net_ops = { 1157 .init = vti6_init_net, 1158 .exit_batch = vti6_exit_batch_net, 1159 .id = &vti6_net_id, 1160 .size = sizeof(struct vti6_net), 1161 }; 1162 1163 static struct xfrm6_protocol vti_esp6_protocol __read_mostly = { 1164 .handler = vti6_rcv, 1165 .cb_handler = vti6_rcv_cb, 1166 .err_handler = vti6_err, 1167 .priority = 100, 1168 }; 1169 1170 static struct xfrm6_protocol vti_ah6_protocol __read_mostly = { 1171 .handler = vti6_rcv, 1172 .cb_handler = vti6_rcv_cb, 1173 .err_handler = vti6_err, 1174 .priority = 100, 1175 }; 1176 1177 static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = { 1178 .handler = vti6_rcv, 1179 .cb_handler = vti6_rcv_cb, 1180 .err_handler = vti6_err, 1181 .priority = 100, 1182 }; 1183 1184 /** 1185 * vti6_tunnel_init - register protocol and reserve needed resources 1186 * 1187 * Return: 0 on success 1188 **/ 1189 static int __init vti6_tunnel_init(void) 1190 { 1191 const char *msg; 1192 int err; 1193 1194 msg = "tunnel device"; 1195 err = register_pernet_device(&vti6_net_ops); 1196 if (err < 0) 1197 goto pernet_dev_failed; 1198 1199 msg = "tunnel protocols"; 1200 err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP); 1201 if (err < 0) 1202 goto xfrm_proto_esp_failed; 1203 err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH); 1204 if (err < 0) 1205 goto xfrm_proto_ah_failed; 1206 err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP); 1207 if (err < 0) 1208 goto xfrm_proto_comp_failed; 1209 1210 msg = "netlink interface"; 1211 err = rtnl_link_register(&vti6_link_ops); 1212 if (err < 0) 1213 goto rtnl_link_failed; 1214 1215 return 0; 1216 1217 rtnl_link_failed: 1218 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); 1219 xfrm_proto_comp_failed: 1220 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); 1221 xfrm_proto_ah_failed: 1222 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); 1223 xfrm_proto_esp_failed: 1224 unregister_pernet_device(&vti6_net_ops); 1225 pernet_dev_failed: 1226 pr_err("vti6 init: failed to register %s\n", msg); 1227 return err; 1228 } 1229 1230 /** 1231 * vti6_tunnel_cleanup - free resources and unregister protocol 1232 **/ 1233 static void __exit vti6_tunnel_cleanup(void) 1234 { 1235 rtnl_link_unregister(&vti6_link_ops); 1236 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); 1237 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); 1238 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); 1239 unregister_pernet_device(&vti6_net_ops); 1240 } 1241 1242 module_init(vti6_tunnel_init); 1243 module_exit(vti6_tunnel_cleanup); 1244 MODULE_LICENSE("GPL"); 1245 MODULE_ALIAS_RTNL_LINK("vti6"); 1246 MODULE_ALIAS_NETDEV("ip6_vti0"); 1247 MODULE_AUTHOR("Steffen Klassert"); 1248 MODULE_DESCRIPTION("IPv6 virtual tunnel interface"); 1249