1 /* 2 * Copyright (c) 2013 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 * 02110-1301, USA 17 */ 18 19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 20 21 #include <linux/capability.h> 22 #include <linux/module.h> 23 #include <linux/types.h> 24 #include <linux/kernel.h> 25 #include <linux/slab.h> 26 #include <linux/uaccess.h> 27 #include <linux/skbuff.h> 28 #include <linux/netdevice.h> 29 #include <linux/in.h> 30 #include <linux/tcp.h> 31 #include <linux/udp.h> 32 #include <linux/if_arp.h> 33 #include <linux/init.h> 34 #include <linux/in6.h> 35 #include <linux/inetdevice.h> 36 #include <linux/igmp.h> 37 #include <linux/netfilter_ipv4.h> 38 #include <linux/etherdevice.h> 39 #include <linux/if_ether.h> 40 #include <linux/if_vlan.h> 41 #include <linux/rculist.h> 42 #include <linux/err.h> 43 44 #include <net/sock.h> 45 #include <net/ip.h> 46 #include <net/icmp.h> 47 #include <net/protocol.h> 48 #include <net/ip_tunnels.h> 49 #include <net/arp.h> 50 #include <net/checksum.h> 51 #include <net/dsfield.h> 52 #include <net/inet_ecn.h> 53 #include <net/xfrm.h> 54 #include <net/net_namespace.h> 55 #include <net/netns/generic.h> 56 #include <net/rtnetlink.h> 57 #include <net/udp.h> 58 #include <net/dst_metadata.h> 59 60 #if IS_ENABLED(CONFIG_IPV6) 61 #include <net/ipv6.h> 62 #include <net/ip6_fib.h> 63 #include <net/ip6_route.h> 64 #endif 65 66 static unsigned int ip_tunnel_hash(__be32 key, __be32 remote) 67 { 68 return hash_32((__force u32)key ^ (__force u32)remote, 69 IP_TNL_HASH_BITS); 70 } 71 72 static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p, 73 __be16 flags, __be32 key) 74 { 75 if (p->i_flags & TUNNEL_KEY) { 76 if (flags & TUNNEL_KEY) 77 return key == p->i_key; 78 else 79 /* key expected, none present */ 80 return false; 81 } else 82 return !(flags & TUNNEL_KEY); 83 } 84 85 /* Fallback tunnel: no source, no destination, no key, no options 86 87 Tunnel hash table: 88 We require exact key match i.e. if a key is present in packet 89 it will match only tunnel with the same key; if it is not present, 90 it will match only keyless tunnel. 91 92 All keysless packets, if not matched configured keyless tunnels 93 will match fallback tunnel. 94 Given src, dst and key, find appropriate for input tunnel. 95 */ 96 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn, 97 int link, __be16 flags, 98 __be32 remote, __be32 local, 99 __be32 key) 100 { 101 unsigned int hash; 102 struct ip_tunnel *t, *cand = NULL; 103 struct hlist_head *head; 104 105 hash = ip_tunnel_hash(key, remote); 106 head = &itn->tunnels[hash]; 107 108 hlist_for_each_entry_rcu(t, head, hash_node) { 109 if (local != t->parms.iph.saddr || 110 remote != t->parms.iph.daddr || 111 !(t->dev->flags & IFF_UP)) 112 continue; 113 114 if (!ip_tunnel_key_match(&t->parms, flags, key)) 115 continue; 116 117 if (t->parms.link == link) 118 return t; 119 else 120 cand = t; 121 } 122 123 hlist_for_each_entry_rcu(t, head, hash_node) { 124 if (remote != t->parms.iph.daddr || 125 t->parms.iph.saddr != 0 || 126 !(t->dev->flags & IFF_UP)) 127 continue; 128 129 if (!ip_tunnel_key_match(&t->parms, flags, key)) 130 continue; 131 132 if (t->parms.link == link) 133 return t; 134 else if (!cand) 135 cand = t; 136 } 137 138 hash = ip_tunnel_hash(key, 0); 139 head = &itn->tunnels[hash]; 140 141 hlist_for_each_entry_rcu(t, head, hash_node) { 142 if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) && 143 (local != t->parms.iph.daddr || !ipv4_is_multicast(local))) 144 continue; 145 146 if (!(t->dev->flags & IFF_UP)) 147 continue; 148 149 if (!ip_tunnel_key_match(&t->parms, flags, key)) 150 continue; 151 152 if (t->parms.link == link) 153 return t; 154 else if (!cand) 155 cand = t; 156 } 157 158 if (flags & TUNNEL_NO_KEY) 159 goto skip_key_lookup; 160 161 hlist_for_each_entry_rcu(t, head, hash_node) { 162 if (t->parms.i_key != key || 163 t->parms.iph.saddr != 0 || 164 t->parms.iph.daddr != 0 || 165 !(t->dev->flags & IFF_UP)) 166 continue; 167 168 if (t->parms.link == link) 169 return t; 170 else if (!cand) 171 cand = t; 172 } 173 174 skip_key_lookup: 175 if (cand) 176 return cand; 177 178 t = rcu_dereference(itn->collect_md_tun); 179 if (t && t->dev->flags & IFF_UP) 180 return t; 181 182 if (itn->fb_tunnel_dev && itn->fb_tunnel_dev->flags & IFF_UP) 183 return netdev_priv(itn->fb_tunnel_dev); 184 185 return NULL; 186 } 187 EXPORT_SYMBOL_GPL(ip_tunnel_lookup); 188 189 static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn, 190 struct ip_tunnel_parm *parms) 191 { 192 unsigned int h; 193 __be32 remote; 194 __be32 i_key = parms->i_key; 195 196 if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr)) 197 remote = parms->iph.daddr; 198 else 199 remote = 0; 200 201 if (!(parms->i_flags & TUNNEL_KEY) && (parms->i_flags & VTI_ISVTI)) 202 i_key = 0; 203 204 h = ip_tunnel_hash(i_key, remote); 205 return &itn->tunnels[h]; 206 } 207 208 static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t) 209 { 210 struct hlist_head *head = ip_bucket(itn, &t->parms); 211 212 if (t->collect_md) 213 rcu_assign_pointer(itn->collect_md_tun, t); 214 hlist_add_head_rcu(&t->hash_node, head); 215 } 216 217 static void ip_tunnel_del(struct ip_tunnel_net *itn, struct ip_tunnel *t) 218 { 219 if (t->collect_md) 220 rcu_assign_pointer(itn->collect_md_tun, NULL); 221 hlist_del_init_rcu(&t->hash_node); 222 } 223 224 static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn, 225 struct ip_tunnel_parm *parms, 226 int type) 227 { 228 __be32 remote = parms->iph.daddr; 229 __be32 local = parms->iph.saddr; 230 __be32 key = parms->i_key; 231 __be16 flags = parms->i_flags; 232 int link = parms->link; 233 struct ip_tunnel *t = NULL; 234 struct hlist_head *head = ip_bucket(itn, parms); 235 236 hlist_for_each_entry_rcu(t, head, hash_node) { 237 if (local == t->parms.iph.saddr && 238 remote == t->parms.iph.daddr && 239 link == t->parms.link && 240 type == t->dev->type && 241 ip_tunnel_key_match(&t->parms, flags, key)) 242 break; 243 } 244 return t; 245 } 246 247 static struct net_device *__ip_tunnel_create(struct net *net, 248 const struct rtnl_link_ops *ops, 249 struct ip_tunnel_parm *parms) 250 { 251 int err; 252 struct ip_tunnel *tunnel; 253 struct net_device *dev; 254 char name[IFNAMSIZ]; 255 256 err = -E2BIG; 257 if (parms->name[0]) { 258 if (!dev_valid_name(parms->name)) 259 goto failed; 260 strlcpy(name, parms->name, IFNAMSIZ); 261 } else { 262 if (strlen(ops->kind) > (IFNAMSIZ - 3)) 263 goto failed; 264 strcpy(name, ops->kind); 265 strcat(name, "%d"); 266 } 267 268 ASSERT_RTNL(); 269 dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup); 270 if (!dev) { 271 err = -ENOMEM; 272 goto failed; 273 } 274 dev_net_set(dev, net); 275 276 dev->rtnl_link_ops = ops; 277 278 tunnel = netdev_priv(dev); 279 tunnel->parms = *parms; 280 tunnel->net = net; 281 282 err = register_netdevice(dev); 283 if (err) 284 goto failed_free; 285 286 return dev; 287 288 failed_free: 289 free_netdev(dev); 290 failed: 291 return ERR_PTR(err); 292 } 293 294 static int ip_tunnel_bind_dev(struct net_device *dev) 295 { 296 struct net_device *tdev = NULL; 297 struct ip_tunnel *tunnel = netdev_priv(dev); 298 const struct iphdr *iph; 299 int hlen = LL_MAX_HEADER; 300 int mtu = ETH_DATA_LEN; 301 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 302 303 iph = &tunnel->parms.iph; 304 305 /* Guess output device to choose reasonable mtu and needed_headroom */ 306 if (iph->daddr) { 307 struct flowi4 fl4; 308 struct rtable *rt; 309 310 ip_tunnel_init_flow(&fl4, iph->protocol, iph->daddr, 311 iph->saddr, tunnel->parms.o_key, 312 RT_TOS(iph->tos), tunnel->parms.link, 313 tunnel->fwmark); 314 rt = ip_route_output_key(tunnel->net, &fl4); 315 316 if (!IS_ERR(rt)) { 317 tdev = rt->dst.dev; 318 ip_rt_put(rt); 319 } 320 if (dev->type != ARPHRD_ETHER) 321 dev->flags |= IFF_POINTOPOINT; 322 323 dst_cache_reset(&tunnel->dst_cache); 324 } 325 326 if (!tdev && tunnel->parms.link) 327 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); 328 329 if (tdev) { 330 hlen = tdev->hard_header_len + tdev->needed_headroom; 331 mtu = min(tdev->mtu, IP_MAX_MTU); 332 } 333 334 dev->needed_headroom = t_hlen + hlen; 335 mtu -= (dev->hard_header_len + t_hlen); 336 337 if (mtu < IPV4_MIN_MTU) 338 mtu = IPV4_MIN_MTU; 339 340 return mtu; 341 } 342 343 static struct ip_tunnel *ip_tunnel_create(struct net *net, 344 struct ip_tunnel_net *itn, 345 struct ip_tunnel_parm *parms) 346 { 347 struct ip_tunnel *nt; 348 struct net_device *dev; 349 int t_hlen; 350 int mtu; 351 int err; 352 353 dev = __ip_tunnel_create(net, itn->rtnl_link_ops, parms); 354 if (IS_ERR(dev)) 355 return ERR_CAST(dev); 356 357 mtu = ip_tunnel_bind_dev(dev); 358 err = dev_set_mtu(dev, mtu); 359 if (err) 360 goto err_dev_set_mtu; 361 362 nt = netdev_priv(dev); 363 t_hlen = nt->hlen + sizeof(struct iphdr); 364 dev->min_mtu = ETH_MIN_MTU; 365 dev->max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen; 366 ip_tunnel_add(itn, nt); 367 return nt; 368 369 err_dev_set_mtu: 370 unregister_netdevice(dev); 371 return ERR_PTR(err); 372 } 373 374 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb, 375 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst, 376 bool log_ecn_error) 377 { 378 struct pcpu_sw_netstats *tstats; 379 const struct iphdr *iph = ip_hdr(skb); 380 int err; 381 382 #ifdef CONFIG_NET_IPGRE_BROADCAST 383 if (ipv4_is_multicast(iph->daddr)) { 384 tunnel->dev->stats.multicast++; 385 skb->pkt_type = PACKET_BROADCAST; 386 } 387 #endif 388 389 if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) || 390 ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) { 391 tunnel->dev->stats.rx_crc_errors++; 392 tunnel->dev->stats.rx_errors++; 393 goto drop; 394 } 395 396 if (tunnel->parms.i_flags&TUNNEL_SEQ) { 397 if (!(tpi->flags&TUNNEL_SEQ) || 398 (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 399 tunnel->dev->stats.rx_fifo_errors++; 400 tunnel->dev->stats.rx_errors++; 401 goto drop; 402 } 403 tunnel->i_seqno = ntohl(tpi->seq) + 1; 404 } 405 406 skb_reset_network_header(skb); 407 408 err = IP_ECN_decapsulate(iph, skb); 409 if (unlikely(err)) { 410 if (log_ecn_error) 411 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", 412 &iph->saddr, iph->tos); 413 if (err > 1) { 414 ++tunnel->dev->stats.rx_frame_errors; 415 ++tunnel->dev->stats.rx_errors; 416 goto drop; 417 } 418 } 419 420 tstats = this_cpu_ptr(tunnel->dev->tstats); 421 u64_stats_update_begin(&tstats->syncp); 422 tstats->rx_packets++; 423 tstats->rx_bytes += skb->len; 424 u64_stats_update_end(&tstats->syncp); 425 426 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 427 428 if (tunnel->dev->type == ARPHRD_ETHER) { 429 skb->protocol = eth_type_trans(skb, tunnel->dev); 430 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 431 } else { 432 skb->dev = tunnel->dev; 433 } 434 435 if (tun_dst) 436 skb_dst_set(skb, (struct dst_entry *)tun_dst); 437 438 gro_cells_receive(&tunnel->gro_cells, skb); 439 return 0; 440 441 drop: 442 if (tun_dst) 443 dst_release((struct dst_entry *)tun_dst); 444 kfree_skb(skb); 445 return 0; 446 } 447 EXPORT_SYMBOL_GPL(ip_tunnel_rcv); 448 449 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops, 450 unsigned int num) 451 { 452 if (num >= MAX_IPTUN_ENCAP_OPS) 453 return -ERANGE; 454 455 return !cmpxchg((const struct ip_tunnel_encap_ops **) 456 &iptun_encaps[num], 457 NULL, ops) ? 0 : -1; 458 } 459 EXPORT_SYMBOL(ip_tunnel_encap_add_ops); 460 461 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops, 462 unsigned int num) 463 { 464 int ret; 465 466 if (num >= MAX_IPTUN_ENCAP_OPS) 467 return -ERANGE; 468 469 ret = (cmpxchg((const struct ip_tunnel_encap_ops **) 470 &iptun_encaps[num], 471 ops, NULL) == ops) ? 0 : -1; 472 473 synchronize_net(); 474 475 return ret; 476 } 477 EXPORT_SYMBOL(ip_tunnel_encap_del_ops); 478 479 int ip_tunnel_encap_setup(struct ip_tunnel *t, 480 struct ip_tunnel_encap *ipencap) 481 { 482 int hlen; 483 484 memset(&t->encap, 0, sizeof(t->encap)); 485 486 hlen = ip_encap_hlen(ipencap); 487 if (hlen < 0) 488 return hlen; 489 490 t->encap.type = ipencap->type; 491 t->encap.sport = ipencap->sport; 492 t->encap.dport = ipencap->dport; 493 t->encap.flags = ipencap->flags; 494 495 t->encap_hlen = hlen; 496 t->hlen = t->encap_hlen + t->tun_hlen; 497 498 return 0; 499 } 500 EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup); 501 502 static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, 503 struct rtable *rt, __be16 df, 504 const struct iphdr *inner_iph) 505 { 506 struct ip_tunnel *tunnel = netdev_priv(dev); 507 int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len; 508 int mtu; 509 510 if (df) 511 mtu = dst_mtu(&rt->dst) - dev->hard_header_len 512 - sizeof(struct iphdr) - tunnel->hlen; 513 else 514 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu; 515 516 skb_dst_update_pmtu(skb, mtu); 517 518 if (skb->protocol == htons(ETH_P_IP)) { 519 if (!skb_is_gso(skb) && 520 (inner_iph->frag_off & htons(IP_DF)) && 521 mtu < pkt_size) { 522 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 523 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); 524 return -E2BIG; 525 } 526 } 527 #if IS_ENABLED(CONFIG_IPV6) 528 else if (skb->protocol == htons(ETH_P_IPV6)) { 529 struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb); 530 531 if (rt6 && mtu < dst_mtu(skb_dst(skb)) && 532 mtu >= IPV6_MIN_MTU) { 533 if ((tunnel->parms.iph.daddr && 534 !ipv4_is_multicast(tunnel->parms.iph.daddr)) || 535 rt6->rt6i_dst.plen == 128) { 536 rt6->rt6i_flags |= RTF_MODIFIED; 537 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu); 538 } 539 } 540 541 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU && 542 mtu < pkt_size) { 543 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 544 return -E2BIG; 545 } 546 } 547 #endif 548 return 0; 549 } 550 551 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto) 552 { 553 struct ip_tunnel *tunnel = netdev_priv(dev); 554 u32 headroom = sizeof(struct iphdr); 555 struct ip_tunnel_info *tun_info; 556 const struct ip_tunnel_key *key; 557 const struct iphdr *inner_iph; 558 struct rtable *rt; 559 struct flowi4 fl4; 560 __be16 df = 0; 561 u8 tos, ttl; 562 563 tun_info = skb_tunnel_info(skb); 564 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 565 ip_tunnel_info_af(tun_info) != AF_INET)) 566 goto tx_error; 567 key = &tun_info->key; 568 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 569 inner_iph = (const struct iphdr *)skb_inner_network_header(skb); 570 tos = key->tos; 571 if (tos == 1) { 572 if (skb->protocol == htons(ETH_P_IP)) 573 tos = inner_iph->tos; 574 else if (skb->protocol == htons(ETH_P_IPV6)) 575 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); 576 } 577 ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 0, 578 RT_TOS(tos), tunnel->parms.link, tunnel->fwmark); 579 if (tunnel->encap.type != TUNNEL_ENCAP_NONE) 580 goto tx_error; 581 rt = ip_route_output_key(tunnel->net, &fl4); 582 if (IS_ERR(rt)) { 583 dev->stats.tx_carrier_errors++; 584 goto tx_error; 585 } 586 if (rt->dst.dev == dev) { 587 ip_rt_put(rt); 588 dev->stats.collisions++; 589 goto tx_error; 590 } 591 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); 592 ttl = key->ttl; 593 if (ttl == 0) { 594 if (skb->protocol == htons(ETH_P_IP)) 595 ttl = inner_iph->ttl; 596 else if (skb->protocol == htons(ETH_P_IPV6)) 597 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; 598 else 599 ttl = ip4_dst_hoplimit(&rt->dst); 600 } 601 if (key->tun_flags & TUNNEL_DONT_FRAGMENT) 602 df = htons(IP_DF); 603 else if (skb->protocol == htons(ETH_P_IP)) 604 df = inner_iph->frag_off & htons(IP_DF); 605 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; 606 if (headroom > dev->needed_headroom) 607 dev->needed_headroom = headroom; 608 609 if (skb_cow_head(skb, dev->needed_headroom)) { 610 ip_rt_put(rt); 611 goto tx_dropped; 612 } 613 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl, 614 df, !net_eq(tunnel->net, dev_net(dev))); 615 return; 616 tx_error: 617 dev->stats.tx_errors++; 618 goto kfree; 619 tx_dropped: 620 dev->stats.tx_dropped++; 621 kfree: 622 kfree_skb(skb); 623 } 624 EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit); 625 626 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 627 const struct iphdr *tnl_params, u8 protocol) 628 { 629 struct ip_tunnel *tunnel = netdev_priv(dev); 630 const struct iphdr *inner_iph; 631 struct flowi4 fl4; 632 u8 tos, ttl; 633 __be16 df; 634 struct rtable *rt; /* Route to the other host */ 635 unsigned int max_headroom; /* The extra header space needed */ 636 __be32 dst; 637 bool connected; 638 639 inner_iph = (const struct iphdr *)skb_inner_network_header(skb); 640 connected = (tunnel->parms.iph.daddr != 0); 641 642 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 643 644 dst = tnl_params->daddr; 645 if (dst == 0) { 646 /* NBMA tunnel */ 647 648 if (!skb_dst(skb)) { 649 dev->stats.tx_fifo_errors++; 650 goto tx_error; 651 } 652 653 if (skb->protocol == htons(ETH_P_IP)) { 654 rt = skb_rtable(skb); 655 dst = rt_nexthop(rt, inner_iph->daddr); 656 } 657 #if IS_ENABLED(CONFIG_IPV6) 658 else if (skb->protocol == htons(ETH_P_IPV6)) { 659 const struct in6_addr *addr6; 660 struct neighbour *neigh; 661 bool do_tx_error_icmp; 662 int addr_type; 663 664 neigh = dst_neigh_lookup(skb_dst(skb), 665 &ipv6_hdr(skb)->daddr); 666 if (!neigh) 667 goto tx_error; 668 669 addr6 = (const struct in6_addr *)&neigh->primary_key; 670 addr_type = ipv6_addr_type(addr6); 671 672 if (addr_type == IPV6_ADDR_ANY) { 673 addr6 = &ipv6_hdr(skb)->daddr; 674 addr_type = ipv6_addr_type(addr6); 675 } 676 677 if ((addr_type & IPV6_ADDR_COMPATv4) == 0) 678 do_tx_error_icmp = true; 679 else { 680 do_tx_error_icmp = false; 681 dst = addr6->s6_addr32[3]; 682 } 683 neigh_release(neigh); 684 if (do_tx_error_icmp) 685 goto tx_error_icmp; 686 } 687 #endif 688 else 689 goto tx_error; 690 691 connected = false; 692 } 693 694 tos = tnl_params->tos; 695 if (tos & 0x1) { 696 tos &= ~0x1; 697 if (skb->protocol == htons(ETH_P_IP)) { 698 tos = inner_iph->tos; 699 connected = false; 700 } else if (skb->protocol == htons(ETH_P_IPV6)) { 701 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); 702 connected = false; 703 } 704 } 705 706 ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr, 707 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link, 708 tunnel->fwmark); 709 710 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) 711 goto tx_error; 712 713 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr) : 714 NULL; 715 716 if (!rt) { 717 rt = ip_route_output_key(tunnel->net, &fl4); 718 719 if (IS_ERR(rt)) { 720 dev->stats.tx_carrier_errors++; 721 goto tx_error; 722 } 723 if (connected) 724 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, 725 fl4.saddr); 726 } 727 728 if (rt->dst.dev == dev) { 729 ip_rt_put(rt); 730 dev->stats.collisions++; 731 goto tx_error; 732 } 733 734 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) { 735 ip_rt_put(rt); 736 goto tx_error; 737 } 738 739 if (tunnel->err_count > 0) { 740 if (time_before(jiffies, 741 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 742 tunnel->err_count--; 743 744 dst_link_failure(skb); 745 } else 746 tunnel->err_count = 0; 747 } 748 749 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); 750 ttl = tnl_params->ttl; 751 if (ttl == 0) { 752 if (skb->protocol == htons(ETH_P_IP)) 753 ttl = inner_iph->ttl; 754 #if IS_ENABLED(CONFIG_IPV6) 755 else if (skb->protocol == htons(ETH_P_IPV6)) 756 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; 757 #endif 758 else 759 ttl = ip4_dst_hoplimit(&rt->dst); 760 } 761 762 df = tnl_params->frag_off; 763 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df) 764 df |= (inner_iph->frag_off&htons(IP_DF)); 765 766 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) 767 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap); 768 if (max_headroom > dev->needed_headroom) 769 dev->needed_headroom = max_headroom; 770 771 if (skb_cow_head(skb, dev->needed_headroom)) { 772 ip_rt_put(rt); 773 dev->stats.tx_dropped++; 774 kfree_skb(skb); 775 return; 776 } 777 778 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, 779 df, !net_eq(tunnel->net, dev_net(dev))); 780 return; 781 782 #if IS_ENABLED(CONFIG_IPV6) 783 tx_error_icmp: 784 dst_link_failure(skb); 785 #endif 786 tx_error: 787 dev->stats.tx_errors++; 788 kfree_skb(skb); 789 } 790 EXPORT_SYMBOL_GPL(ip_tunnel_xmit); 791 792 static void ip_tunnel_update(struct ip_tunnel_net *itn, 793 struct ip_tunnel *t, 794 struct net_device *dev, 795 struct ip_tunnel_parm *p, 796 bool set_mtu, 797 __u32 fwmark) 798 { 799 ip_tunnel_del(itn, t); 800 t->parms.iph.saddr = p->iph.saddr; 801 t->parms.iph.daddr = p->iph.daddr; 802 t->parms.i_key = p->i_key; 803 t->parms.o_key = p->o_key; 804 if (dev->type != ARPHRD_ETHER) { 805 memcpy(dev->dev_addr, &p->iph.saddr, 4); 806 memcpy(dev->broadcast, &p->iph.daddr, 4); 807 } 808 ip_tunnel_add(itn, t); 809 810 t->parms.iph.ttl = p->iph.ttl; 811 t->parms.iph.tos = p->iph.tos; 812 t->parms.iph.frag_off = p->iph.frag_off; 813 814 if (t->parms.link != p->link || t->fwmark != fwmark) { 815 int mtu; 816 817 t->parms.link = p->link; 818 t->fwmark = fwmark; 819 mtu = ip_tunnel_bind_dev(dev); 820 if (set_mtu) 821 dev->mtu = mtu; 822 } 823 dst_cache_reset(&t->dst_cache); 824 netdev_state_change(dev); 825 } 826 827 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) 828 { 829 int err = 0; 830 struct ip_tunnel *t = netdev_priv(dev); 831 struct net *net = t->net; 832 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id); 833 834 switch (cmd) { 835 case SIOCGETTUNNEL: 836 if (dev == itn->fb_tunnel_dev) { 837 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 838 if (!t) 839 t = netdev_priv(dev); 840 } 841 memcpy(p, &t->parms, sizeof(*p)); 842 break; 843 844 case SIOCADDTUNNEL: 845 case SIOCCHGTUNNEL: 846 err = -EPERM; 847 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 848 goto done; 849 if (p->iph.ttl) 850 p->iph.frag_off |= htons(IP_DF); 851 if (!(p->i_flags & VTI_ISVTI)) { 852 if (!(p->i_flags & TUNNEL_KEY)) 853 p->i_key = 0; 854 if (!(p->o_flags & TUNNEL_KEY)) 855 p->o_key = 0; 856 } 857 858 t = ip_tunnel_find(itn, p, itn->type); 859 860 if (cmd == SIOCADDTUNNEL) { 861 if (!t) { 862 t = ip_tunnel_create(net, itn, p); 863 err = PTR_ERR_OR_ZERO(t); 864 break; 865 } 866 867 err = -EEXIST; 868 break; 869 } 870 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 871 if (t) { 872 if (t->dev != dev) { 873 err = -EEXIST; 874 break; 875 } 876 } else { 877 unsigned int nflags = 0; 878 879 if (ipv4_is_multicast(p->iph.daddr)) 880 nflags = IFF_BROADCAST; 881 else if (p->iph.daddr) 882 nflags = IFF_POINTOPOINT; 883 884 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) { 885 err = -EINVAL; 886 break; 887 } 888 889 t = netdev_priv(dev); 890 } 891 } 892 893 if (t) { 894 err = 0; 895 ip_tunnel_update(itn, t, dev, p, true, 0); 896 } else { 897 err = -ENOENT; 898 } 899 break; 900 901 case SIOCDELTUNNEL: 902 err = -EPERM; 903 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 904 goto done; 905 906 if (dev == itn->fb_tunnel_dev) { 907 err = -ENOENT; 908 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 909 if (!t) 910 goto done; 911 err = -EPERM; 912 if (t == netdev_priv(itn->fb_tunnel_dev)) 913 goto done; 914 dev = t->dev; 915 } 916 unregister_netdevice(dev); 917 err = 0; 918 break; 919 920 default: 921 err = -EINVAL; 922 } 923 924 done: 925 return err; 926 } 927 EXPORT_SYMBOL_GPL(ip_tunnel_ioctl); 928 929 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict) 930 { 931 struct ip_tunnel *tunnel = netdev_priv(dev); 932 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 933 int max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen; 934 935 if (new_mtu < ETH_MIN_MTU) 936 return -EINVAL; 937 938 if (new_mtu > max_mtu) { 939 if (strict) 940 return -EINVAL; 941 942 new_mtu = max_mtu; 943 } 944 945 dev->mtu = new_mtu; 946 return 0; 947 } 948 EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu); 949 950 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu) 951 { 952 return __ip_tunnel_change_mtu(dev, new_mtu, true); 953 } 954 EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu); 955 956 static void ip_tunnel_dev_free(struct net_device *dev) 957 { 958 struct ip_tunnel *tunnel = netdev_priv(dev); 959 960 gro_cells_destroy(&tunnel->gro_cells); 961 dst_cache_destroy(&tunnel->dst_cache); 962 free_percpu(dev->tstats); 963 } 964 965 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head) 966 { 967 struct ip_tunnel *tunnel = netdev_priv(dev); 968 struct ip_tunnel_net *itn; 969 970 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id); 971 972 if (itn->fb_tunnel_dev != dev) { 973 ip_tunnel_del(itn, netdev_priv(dev)); 974 unregister_netdevice_queue(dev, head); 975 } 976 } 977 EXPORT_SYMBOL_GPL(ip_tunnel_dellink); 978 979 struct net *ip_tunnel_get_link_net(const struct net_device *dev) 980 { 981 struct ip_tunnel *tunnel = netdev_priv(dev); 982 983 return tunnel->net; 984 } 985 EXPORT_SYMBOL(ip_tunnel_get_link_net); 986 987 int ip_tunnel_get_iflink(const struct net_device *dev) 988 { 989 struct ip_tunnel *tunnel = netdev_priv(dev); 990 991 return tunnel->parms.link; 992 } 993 EXPORT_SYMBOL(ip_tunnel_get_iflink); 994 995 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, 996 struct rtnl_link_ops *ops, char *devname) 997 { 998 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id); 999 struct ip_tunnel_parm parms; 1000 unsigned int i; 1001 1002 itn->rtnl_link_ops = ops; 1003 for (i = 0; i < IP_TNL_HASH_SIZE; i++) 1004 INIT_HLIST_HEAD(&itn->tunnels[i]); 1005 1006 if (!ops || !net_has_fallback_tunnels(net)) { 1007 struct ip_tunnel_net *it_init_net; 1008 1009 it_init_net = net_generic(&init_net, ip_tnl_net_id); 1010 itn->type = it_init_net->type; 1011 itn->fb_tunnel_dev = NULL; 1012 return 0; 1013 } 1014 1015 memset(&parms, 0, sizeof(parms)); 1016 if (devname) 1017 strlcpy(parms.name, devname, IFNAMSIZ); 1018 1019 rtnl_lock(); 1020 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms); 1021 /* FB netdevice is special: we have one, and only one per netns. 1022 * Allowing to move it to another netns is clearly unsafe. 1023 */ 1024 if (!IS_ERR(itn->fb_tunnel_dev)) { 1025 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1026 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev); 1027 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev)); 1028 itn->type = itn->fb_tunnel_dev->type; 1029 } 1030 rtnl_unlock(); 1031 1032 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev); 1033 } 1034 EXPORT_SYMBOL_GPL(ip_tunnel_init_net); 1035 1036 static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn, 1037 struct list_head *head, 1038 struct rtnl_link_ops *ops) 1039 { 1040 struct net_device *dev, *aux; 1041 int h; 1042 1043 for_each_netdev_safe(net, dev, aux) 1044 if (dev->rtnl_link_ops == ops) 1045 unregister_netdevice_queue(dev, head); 1046 1047 for (h = 0; h < IP_TNL_HASH_SIZE; h++) { 1048 struct ip_tunnel *t; 1049 struct hlist_node *n; 1050 struct hlist_head *thead = &itn->tunnels[h]; 1051 1052 hlist_for_each_entry_safe(t, n, thead, hash_node) 1053 /* If dev is in the same netns, it has already 1054 * been added to the list by the previous loop. 1055 */ 1056 if (!net_eq(dev_net(t->dev), net)) 1057 unregister_netdevice_queue(t->dev, head); 1058 } 1059 } 1060 1061 void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id, 1062 struct rtnl_link_ops *ops) 1063 { 1064 struct ip_tunnel_net *itn; 1065 struct net *net; 1066 LIST_HEAD(list); 1067 1068 rtnl_lock(); 1069 list_for_each_entry(net, net_list, exit_list) { 1070 itn = net_generic(net, id); 1071 ip_tunnel_destroy(net, itn, &list, ops); 1072 } 1073 unregister_netdevice_many(&list); 1074 rtnl_unlock(); 1075 } 1076 EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets); 1077 1078 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 1079 struct ip_tunnel_parm *p, __u32 fwmark) 1080 { 1081 struct ip_tunnel *nt; 1082 struct net *net = dev_net(dev); 1083 struct ip_tunnel_net *itn; 1084 int mtu; 1085 int err; 1086 1087 nt = netdev_priv(dev); 1088 itn = net_generic(net, nt->ip_tnl_net_id); 1089 1090 if (nt->collect_md) { 1091 if (rtnl_dereference(itn->collect_md_tun)) 1092 return -EEXIST; 1093 } else { 1094 if (ip_tunnel_find(itn, p, dev->type)) 1095 return -EEXIST; 1096 } 1097 1098 nt->net = net; 1099 nt->parms = *p; 1100 nt->fwmark = fwmark; 1101 err = register_netdevice(dev); 1102 if (err) 1103 goto err_register_netdevice; 1104 1105 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1106 eth_hw_addr_random(dev); 1107 1108 mtu = ip_tunnel_bind_dev(dev); 1109 if (tb[IFLA_MTU]) { 1110 unsigned int max = IP_MAX_MTU - dev->hard_header_len - nt->hlen; 1111 1112 mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU, 1113 (unsigned int)(max - sizeof(struct iphdr))); 1114 } 1115 1116 err = dev_set_mtu(dev, mtu); 1117 if (err) 1118 goto err_dev_set_mtu; 1119 1120 ip_tunnel_add(itn, nt); 1121 return 0; 1122 1123 err_dev_set_mtu: 1124 unregister_netdevice(dev); 1125 err_register_netdevice: 1126 return err; 1127 } 1128 EXPORT_SYMBOL_GPL(ip_tunnel_newlink); 1129 1130 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], 1131 struct ip_tunnel_parm *p, __u32 fwmark) 1132 { 1133 struct ip_tunnel *t; 1134 struct ip_tunnel *tunnel = netdev_priv(dev); 1135 struct net *net = tunnel->net; 1136 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id); 1137 1138 if (dev == itn->fb_tunnel_dev) 1139 return -EINVAL; 1140 1141 t = ip_tunnel_find(itn, p, dev->type); 1142 1143 if (t) { 1144 if (t->dev != dev) 1145 return -EEXIST; 1146 } else { 1147 t = tunnel; 1148 1149 if (dev->type != ARPHRD_ETHER) { 1150 unsigned int nflags = 0; 1151 1152 if (ipv4_is_multicast(p->iph.daddr)) 1153 nflags = IFF_BROADCAST; 1154 else if (p->iph.daddr) 1155 nflags = IFF_POINTOPOINT; 1156 1157 if ((dev->flags ^ nflags) & 1158 (IFF_POINTOPOINT | IFF_BROADCAST)) 1159 return -EINVAL; 1160 } 1161 } 1162 1163 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark); 1164 return 0; 1165 } 1166 EXPORT_SYMBOL_GPL(ip_tunnel_changelink); 1167 1168 int ip_tunnel_init(struct net_device *dev) 1169 { 1170 struct ip_tunnel *tunnel = netdev_priv(dev); 1171 struct iphdr *iph = &tunnel->parms.iph; 1172 int err; 1173 1174 dev->needs_free_netdev = true; 1175 dev->priv_destructor = ip_tunnel_dev_free; 1176 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1177 if (!dev->tstats) 1178 return -ENOMEM; 1179 1180 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1181 if (err) { 1182 free_percpu(dev->tstats); 1183 return err; 1184 } 1185 1186 err = gro_cells_init(&tunnel->gro_cells, dev); 1187 if (err) { 1188 dst_cache_destroy(&tunnel->dst_cache); 1189 free_percpu(dev->tstats); 1190 return err; 1191 } 1192 1193 tunnel->dev = dev; 1194 tunnel->net = dev_net(dev); 1195 strcpy(tunnel->parms.name, dev->name); 1196 iph->version = 4; 1197 iph->ihl = 5; 1198 1199 if (tunnel->collect_md) { 1200 dev->features |= NETIF_F_NETNS_LOCAL; 1201 netif_keep_dst(dev); 1202 } 1203 return 0; 1204 } 1205 EXPORT_SYMBOL_GPL(ip_tunnel_init); 1206 1207 void ip_tunnel_uninit(struct net_device *dev) 1208 { 1209 struct ip_tunnel *tunnel = netdev_priv(dev); 1210 struct net *net = tunnel->net; 1211 struct ip_tunnel_net *itn; 1212 1213 itn = net_generic(net, tunnel->ip_tnl_net_id); 1214 /* fb_tunnel_dev will be unregisted in net-exit call. */ 1215 if (itn->fb_tunnel_dev != dev) 1216 ip_tunnel_del(itn, netdev_priv(dev)); 1217 1218 dst_cache_reset(&tunnel->dst_cache); 1219 } 1220 EXPORT_SYMBOL_GPL(ip_tunnel_uninit); 1221 1222 /* Do least required initialization, rest of init is done in tunnel_init call */ 1223 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id) 1224 { 1225 struct ip_tunnel *tunnel = netdev_priv(dev); 1226 tunnel->ip_tnl_net_id = net_id; 1227 } 1228 EXPORT_SYMBOL_GPL(ip_tunnel_setup); 1229 1230 MODULE_LICENSE("GPL"); 1231