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 struct ip_tunnel_info *tun_info; 648 649 if (!skb_dst(skb)) { 650 dev->stats.tx_fifo_errors++; 651 goto tx_error; 652 } 653 654 tun_info = skb_tunnel_info(skb); 655 if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX) && 656 ip_tunnel_info_af(tun_info) == AF_INET && 657 tun_info->key.u.ipv4.dst) 658 dst = tun_info->key.u.ipv4.dst; 659 else if (skb->protocol == htons(ETH_P_IP)) { 660 rt = skb_rtable(skb); 661 dst = rt_nexthop(rt, inner_iph->daddr); 662 } 663 #if IS_ENABLED(CONFIG_IPV6) 664 else if (skb->protocol == htons(ETH_P_IPV6)) { 665 const struct in6_addr *addr6; 666 struct neighbour *neigh; 667 bool do_tx_error_icmp; 668 int addr_type; 669 670 neigh = dst_neigh_lookup(skb_dst(skb), 671 &ipv6_hdr(skb)->daddr); 672 if (!neigh) 673 goto tx_error; 674 675 addr6 = (const struct in6_addr *)&neigh->primary_key; 676 addr_type = ipv6_addr_type(addr6); 677 678 if (addr_type == IPV6_ADDR_ANY) { 679 addr6 = &ipv6_hdr(skb)->daddr; 680 addr_type = ipv6_addr_type(addr6); 681 } 682 683 if ((addr_type & IPV6_ADDR_COMPATv4) == 0) 684 do_tx_error_icmp = true; 685 else { 686 do_tx_error_icmp = false; 687 dst = addr6->s6_addr32[3]; 688 } 689 neigh_release(neigh); 690 if (do_tx_error_icmp) 691 goto tx_error_icmp; 692 } 693 #endif 694 else 695 goto tx_error; 696 697 connected = false; 698 } 699 700 tos = tnl_params->tos; 701 if (tos & 0x1) { 702 tos &= ~0x1; 703 if (skb->protocol == htons(ETH_P_IP)) { 704 tos = inner_iph->tos; 705 connected = false; 706 } else if (skb->protocol == htons(ETH_P_IPV6)) { 707 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); 708 connected = false; 709 } 710 } 711 712 ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr, 713 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link, 714 tunnel->fwmark); 715 716 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) 717 goto tx_error; 718 719 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr) : 720 NULL; 721 722 if (!rt) { 723 rt = ip_route_output_key(tunnel->net, &fl4); 724 725 if (IS_ERR(rt)) { 726 dev->stats.tx_carrier_errors++; 727 goto tx_error; 728 } 729 if (connected) 730 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, 731 fl4.saddr); 732 } 733 734 if (rt->dst.dev == dev) { 735 ip_rt_put(rt); 736 dev->stats.collisions++; 737 goto tx_error; 738 } 739 740 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) { 741 ip_rt_put(rt); 742 goto tx_error; 743 } 744 745 if (tunnel->err_count > 0) { 746 if (time_before(jiffies, 747 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 748 tunnel->err_count--; 749 750 dst_link_failure(skb); 751 } else 752 tunnel->err_count = 0; 753 } 754 755 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); 756 ttl = tnl_params->ttl; 757 if (ttl == 0) { 758 if (skb->protocol == htons(ETH_P_IP)) 759 ttl = inner_iph->ttl; 760 #if IS_ENABLED(CONFIG_IPV6) 761 else if (skb->protocol == htons(ETH_P_IPV6)) 762 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; 763 #endif 764 else 765 ttl = ip4_dst_hoplimit(&rt->dst); 766 } 767 768 df = tnl_params->frag_off; 769 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df) 770 df |= (inner_iph->frag_off&htons(IP_DF)); 771 772 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) 773 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap); 774 if (max_headroom > dev->needed_headroom) 775 dev->needed_headroom = max_headroom; 776 777 if (skb_cow_head(skb, dev->needed_headroom)) { 778 ip_rt_put(rt); 779 dev->stats.tx_dropped++; 780 kfree_skb(skb); 781 return; 782 } 783 784 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, 785 df, !net_eq(tunnel->net, dev_net(dev))); 786 return; 787 788 #if IS_ENABLED(CONFIG_IPV6) 789 tx_error_icmp: 790 dst_link_failure(skb); 791 #endif 792 tx_error: 793 dev->stats.tx_errors++; 794 kfree_skb(skb); 795 } 796 EXPORT_SYMBOL_GPL(ip_tunnel_xmit); 797 798 static void ip_tunnel_update(struct ip_tunnel_net *itn, 799 struct ip_tunnel *t, 800 struct net_device *dev, 801 struct ip_tunnel_parm *p, 802 bool set_mtu, 803 __u32 fwmark) 804 { 805 ip_tunnel_del(itn, t); 806 t->parms.iph.saddr = p->iph.saddr; 807 t->parms.iph.daddr = p->iph.daddr; 808 t->parms.i_key = p->i_key; 809 t->parms.o_key = p->o_key; 810 if (dev->type != ARPHRD_ETHER) { 811 memcpy(dev->dev_addr, &p->iph.saddr, 4); 812 memcpy(dev->broadcast, &p->iph.daddr, 4); 813 } 814 ip_tunnel_add(itn, t); 815 816 t->parms.iph.ttl = p->iph.ttl; 817 t->parms.iph.tos = p->iph.tos; 818 t->parms.iph.frag_off = p->iph.frag_off; 819 820 if (t->parms.link != p->link || t->fwmark != fwmark) { 821 int mtu; 822 823 t->parms.link = p->link; 824 t->fwmark = fwmark; 825 mtu = ip_tunnel_bind_dev(dev); 826 if (set_mtu) 827 dev->mtu = mtu; 828 } 829 dst_cache_reset(&t->dst_cache); 830 netdev_state_change(dev); 831 } 832 833 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) 834 { 835 int err = 0; 836 struct ip_tunnel *t = netdev_priv(dev); 837 struct net *net = t->net; 838 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id); 839 840 switch (cmd) { 841 case SIOCGETTUNNEL: 842 if (dev == itn->fb_tunnel_dev) { 843 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 844 if (!t) 845 t = netdev_priv(dev); 846 } 847 memcpy(p, &t->parms, sizeof(*p)); 848 break; 849 850 case SIOCADDTUNNEL: 851 case SIOCCHGTUNNEL: 852 err = -EPERM; 853 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 854 goto done; 855 if (p->iph.ttl) 856 p->iph.frag_off |= htons(IP_DF); 857 if (!(p->i_flags & VTI_ISVTI)) { 858 if (!(p->i_flags & TUNNEL_KEY)) 859 p->i_key = 0; 860 if (!(p->o_flags & TUNNEL_KEY)) 861 p->o_key = 0; 862 } 863 864 t = ip_tunnel_find(itn, p, itn->type); 865 866 if (cmd == SIOCADDTUNNEL) { 867 if (!t) { 868 t = ip_tunnel_create(net, itn, p); 869 err = PTR_ERR_OR_ZERO(t); 870 break; 871 } 872 873 err = -EEXIST; 874 break; 875 } 876 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 877 if (t) { 878 if (t->dev != dev) { 879 err = -EEXIST; 880 break; 881 } 882 } else { 883 unsigned int nflags = 0; 884 885 if (ipv4_is_multicast(p->iph.daddr)) 886 nflags = IFF_BROADCAST; 887 else if (p->iph.daddr) 888 nflags = IFF_POINTOPOINT; 889 890 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) { 891 err = -EINVAL; 892 break; 893 } 894 895 t = netdev_priv(dev); 896 } 897 } 898 899 if (t) { 900 err = 0; 901 ip_tunnel_update(itn, t, dev, p, true, 0); 902 } else { 903 err = -ENOENT; 904 } 905 break; 906 907 case SIOCDELTUNNEL: 908 err = -EPERM; 909 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 910 goto done; 911 912 if (dev == itn->fb_tunnel_dev) { 913 err = -ENOENT; 914 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 915 if (!t) 916 goto done; 917 err = -EPERM; 918 if (t == netdev_priv(itn->fb_tunnel_dev)) 919 goto done; 920 dev = t->dev; 921 } 922 unregister_netdevice(dev); 923 err = 0; 924 break; 925 926 default: 927 err = -EINVAL; 928 } 929 930 done: 931 return err; 932 } 933 EXPORT_SYMBOL_GPL(ip_tunnel_ioctl); 934 935 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict) 936 { 937 struct ip_tunnel *tunnel = netdev_priv(dev); 938 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 939 int max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen; 940 941 if (new_mtu < ETH_MIN_MTU) 942 return -EINVAL; 943 944 if (new_mtu > max_mtu) { 945 if (strict) 946 return -EINVAL; 947 948 new_mtu = max_mtu; 949 } 950 951 dev->mtu = new_mtu; 952 return 0; 953 } 954 EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu); 955 956 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu) 957 { 958 return __ip_tunnel_change_mtu(dev, new_mtu, true); 959 } 960 EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu); 961 962 static void ip_tunnel_dev_free(struct net_device *dev) 963 { 964 struct ip_tunnel *tunnel = netdev_priv(dev); 965 966 gro_cells_destroy(&tunnel->gro_cells); 967 dst_cache_destroy(&tunnel->dst_cache); 968 free_percpu(dev->tstats); 969 } 970 971 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head) 972 { 973 struct ip_tunnel *tunnel = netdev_priv(dev); 974 struct ip_tunnel_net *itn; 975 976 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id); 977 978 if (itn->fb_tunnel_dev != dev) { 979 ip_tunnel_del(itn, netdev_priv(dev)); 980 unregister_netdevice_queue(dev, head); 981 } 982 } 983 EXPORT_SYMBOL_GPL(ip_tunnel_dellink); 984 985 struct net *ip_tunnel_get_link_net(const struct net_device *dev) 986 { 987 struct ip_tunnel *tunnel = netdev_priv(dev); 988 989 return tunnel->net; 990 } 991 EXPORT_SYMBOL(ip_tunnel_get_link_net); 992 993 int ip_tunnel_get_iflink(const struct net_device *dev) 994 { 995 struct ip_tunnel *tunnel = netdev_priv(dev); 996 997 return tunnel->parms.link; 998 } 999 EXPORT_SYMBOL(ip_tunnel_get_iflink); 1000 1001 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, 1002 struct rtnl_link_ops *ops, char *devname) 1003 { 1004 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id); 1005 struct ip_tunnel_parm parms; 1006 unsigned int i; 1007 1008 itn->rtnl_link_ops = ops; 1009 for (i = 0; i < IP_TNL_HASH_SIZE; i++) 1010 INIT_HLIST_HEAD(&itn->tunnels[i]); 1011 1012 if (!ops || !net_has_fallback_tunnels(net)) { 1013 struct ip_tunnel_net *it_init_net; 1014 1015 it_init_net = net_generic(&init_net, ip_tnl_net_id); 1016 itn->type = it_init_net->type; 1017 itn->fb_tunnel_dev = NULL; 1018 return 0; 1019 } 1020 1021 memset(&parms, 0, sizeof(parms)); 1022 if (devname) 1023 strlcpy(parms.name, devname, IFNAMSIZ); 1024 1025 rtnl_lock(); 1026 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms); 1027 /* FB netdevice is special: we have one, and only one per netns. 1028 * Allowing to move it to another netns is clearly unsafe. 1029 */ 1030 if (!IS_ERR(itn->fb_tunnel_dev)) { 1031 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1032 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev); 1033 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev)); 1034 itn->type = itn->fb_tunnel_dev->type; 1035 } 1036 rtnl_unlock(); 1037 1038 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev); 1039 } 1040 EXPORT_SYMBOL_GPL(ip_tunnel_init_net); 1041 1042 static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn, 1043 struct list_head *head, 1044 struct rtnl_link_ops *ops) 1045 { 1046 struct net_device *dev, *aux; 1047 int h; 1048 1049 for_each_netdev_safe(net, dev, aux) 1050 if (dev->rtnl_link_ops == ops) 1051 unregister_netdevice_queue(dev, head); 1052 1053 for (h = 0; h < IP_TNL_HASH_SIZE; h++) { 1054 struct ip_tunnel *t; 1055 struct hlist_node *n; 1056 struct hlist_head *thead = &itn->tunnels[h]; 1057 1058 hlist_for_each_entry_safe(t, n, thead, hash_node) 1059 /* If dev is in the same netns, it has already 1060 * been added to the list by the previous loop. 1061 */ 1062 if (!net_eq(dev_net(t->dev), net)) 1063 unregister_netdevice_queue(t->dev, head); 1064 } 1065 } 1066 1067 void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id, 1068 struct rtnl_link_ops *ops) 1069 { 1070 struct ip_tunnel_net *itn; 1071 struct net *net; 1072 LIST_HEAD(list); 1073 1074 rtnl_lock(); 1075 list_for_each_entry(net, net_list, exit_list) { 1076 itn = net_generic(net, id); 1077 ip_tunnel_destroy(net, itn, &list, ops); 1078 } 1079 unregister_netdevice_many(&list); 1080 rtnl_unlock(); 1081 } 1082 EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets); 1083 1084 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 1085 struct ip_tunnel_parm *p, __u32 fwmark) 1086 { 1087 struct ip_tunnel *nt; 1088 struct net *net = dev_net(dev); 1089 struct ip_tunnel_net *itn; 1090 int mtu; 1091 int err; 1092 1093 nt = netdev_priv(dev); 1094 itn = net_generic(net, nt->ip_tnl_net_id); 1095 1096 if (nt->collect_md) { 1097 if (rtnl_dereference(itn->collect_md_tun)) 1098 return -EEXIST; 1099 } else { 1100 if (ip_tunnel_find(itn, p, dev->type)) 1101 return -EEXIST; 1102 } 1103 1104 nt->net = net; 1105 nt->parms = *p; 1106 nt->fwmark = fwmark; 1107 err = register_netdevice(dev); 1108 if (err) 1109 goto err_register_netdevice; 1110 1111 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1112 eth_hw_addr_random(dev); 1113 1114 mtu = ip_tunnel_bind_dev(dev); 1115 if (tb[IFLA_MTU]) { 1116 unsigned int max = IP_MAX_MTU - dev->hard_header_len - nt->hlen; 1117 1118 mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU, 1119 (unsigned int)(max - sizeof(struct iphdr))); 1120 } 1121 1122 err = dev_set_mtu(dev, mtu); 1123 if (err) 1124 goto err_dev_set_mtu; 1125 1126 ip_tunnel_add(itn, nt); 1127 return 0; 1128 1129 err_dev_set_mtu: 1130 unregister_netdevice(dev); 1131 err_register_netdevice: 1132 return err; 1133 } 1134 EXPORT_SYMBOL_GPL(ip_tunnel_newlink); 1135 1136 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], 1137 struct ip_tunnel_parm *p, __u32 fwmark) 1138 { 1139 struct ip_tunnel *t; 1140 struct ip_tunnel *tunnel = netdev_priv(dev); 1141 struct net *net = tunnel->net; 1142 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id); 1143 1144 if (dev == itn->fb_tunnel_dev) 1145 return -EINVAL; 1146 1147 t = ip_tunnel_find(itn, p, dev->type); 1148 1149 if (t) { 1150 if (t->dev != dev) 1151 return -EEXIST; 1152 } else { 1153 t = tunnel; 1154 1155 if (dev->type != ARPHRD_ETHER) { 1156 unsigned int nflags = 0; 1157 1158 if (ipv4_is_multicast(p->iph.daddr)) 1159 nflags = IFF_BROADCAST; 1160 else if (p->iph.daddr) 1161 nflags = IFF_POINTOPOINT; 1162 1163 if ((dev->flags ^ nflags) & 1164 (IFF_POINTOPOINT | IFF_BROADCAST)) 1165 return -EINVAL; 1166 } 1167 } 1168 1169 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark); 1170 return 0; 1171 } 1172 EXPORT_SYMBOL_GPL(ip_tunnel_changelink); 1173 1174 int ip_tunnel_init(struct net_device *dev) 1175 { 1176 struct ip_tunnel *tunnel = netdev_priv(dev); 1177 struct iphdr *iph = &tunnel->parms.iph; 1178 int err; 1179 1180 dev->needs_free_netdev = true; 1181 dev->priv_destructor = ip_tunnel_dev_free; 1182 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1183 if (!dev->tstats) 1184 return -ENOMEM; 1185 1186 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1187 if (err) { 1188 free_percpu(dev->tstats); 1189 return err; 1190 } 1191 1192 err = gro_cells_init(&tunnel->gro_cells, dev); 1193 if (err) { 1194 dst_cache_destroy(&tunnel->dst_cache); 1195 free_percpu(dev->tstats); 1196 return err; 1197 } 1198 1199 tunnel->dev = dev; 1200 tunnel->net = dev_net(dev); 1201 strcpy(tunnel->parms.name, dev->name); 1202 iph->version = 4; 1203 iph->ihl = 5; 1204 1205 if (tunnel->collect_md) { 1206 dev->features |= NETIF_F_NETNS_LOCAL; 1207 netif_keep_dst(dev); 1208 } 1209 return 0; 1210 } 1211 EXPORT_SYMBOL_GPL(ip_tunnel_init); 1212 1213 void ip_tunnel_uninit(struct net_device *dev) 1214 { 1215 struct ip_tunnel *tunnel = netdev_priv(dev); 1216 struct net *net = tunnel->net; 1217 struct ip_tunnel_net *itn; 1218 1219 itn = net_generic(net, tunnel->ip_tnl_net_id); 1220 /* fb_tunnel_dev will be unregisted in net-exit call. */ 1221 if (itn->fb_tunnel_dev != dev) 1222 ip_tunnel_del(itn, netdev_priv(dev)); 1223 1224 dst_cache_reset(&tunnel->dst_cache); 1225 } 1226 EXPORT_SYMBOL_GPL(ip_tunnel_uninit); 1227 1228 /* Do least required initialization, rest of init is done in tunnel_init call */ 1229 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id) 1230 { 1231 struct ip_tunnel *tunnel = netdev_priv(dev); 1232 tunnel->ip_tnl_net_id = net_id; 1233 } 1234 EXPORT_SYMBOL_GPL(ip_tunnel_setup); 1235 1236 MODULE_LICENSE("GPL"); 1237