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 if (parms->name[0]) 257 strlcpy(name, parms->name, IFNAMSIZ); 258 else { 259 if (strlen(ops->kind) > (IFNAMSIZ - 3)) { 260 err = -E2BIG; 261 goto failed; 262 } 263 strlcpy(name, ops->kind, IFNAMSIZ); 264 strncat(name, "%d", 2); 265 } 266 267 ASSERT_RTNL(); 268 dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup); 269 if (!dev) { 270 err = -ENOMEM; 271 goto failed; 272 } 273 dev_net_set(dev, net); 274 275 dev->rtnl_link_ops = ops; 276 277 tunnel = netdev_priv(dev); 278 tunnel->parms = *parms; 279 tunnel->net = net; 280 281 err = register_netdevice(dev); 282 if (err) 283 goto failed_free; 284 285 return dev; 286 287 failed_free: 288 free_netdev(dev); 289 failed: 290 return ERR_PTR(err); 291 } 292 293 static inline void init_tunnel_flow(struct flowi4 *fl4, 294 int proto, 295 __be32 daddr, __be32 saddr, 296 __be32 key, __u8 tos, int oif, 297 __u32 mark) 298 { 299 memset(fl4, 0, sizeof(*fl4)); 300 fl4->flowi4_oif = oif; 301 fl4->daddr = daddr; 302 fl4->saddr = saddr; 303 fl4->flowi4_tos = tos; 304 fl4->flowi4_proto = proto; 305 fl4->fl4_gre_key = key; 306 fl4->flowi4_mark = mark; 307 } 308 309 static int ip_tunnel_bind_dev(struct net_device *dev) 310 { 311 struct net_device *tdev = NULL; 312 struct ip_tunnel *tunnel = netdev_priv(dev); 313 const struct iphdr *iph; 314 int hlen = LL_MAX_HEADER; 315 int mtu = ETH_DATA_LEN; 316 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 317 318 iph = &tunnel->parms.iph; 319 320 /* Guess output device to choose reasonable mtu and needed_headroom */ 321 if (iph->daddr) { 322 struct flowi4 fl4; 323 struct rtable *rt; 324 325 init_tunnel_flow(&fl4, iph->protocol, iph->daddr, 326 iph->saddr, tunnel->parms.o_key, 327 RT_TOS(iph->tos), tunnel->parms.link, 328 tunnel->fwmark); 329 rt = ip_route_output_key(tunnel->net, &fl4); 330 331 if (!IS_ERR(rt)) { 332 tdev = rt->dst.dev; 333 ip_rt_put(rt); 334 } 335 if (dev->type != ARPHRD_ETHER) 336 dev->flags |= IFF_POINTOPOINT; 337 338 dst_cache_reset(&tunnel->dst_cache); 339 } 340 341 if (!tdev && tunnel->parms.link) 342 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); 343 344 if (tdev) { 345 hlen = tdev->hard_header_len + tdev->needed_headroom; 346 mtu = tdev->mtu; 347 } 348 349 dev->needed_headroom = t_hlen + hlen; 350 mtu -= (dev->hard_header_len + t_hlen); 351 352 if (mtu < IPV4_MIN_MTU) 353 mtu = IPV4_MIN_MTU; 354 355 return mtu; 356 } 357 358 static struct ip_tunnel *ip_tunnel_create(struct net *net, 359 struct ip_tunnel_net *itn, 360 struct ip_tunnel_parm *parms) 361 { 362 struct ip_tunnel *nt; 363 struct net_device *dev; 364 int t_hlen; 365 366 BUG_ON(!itn->fb_tunnel_dev); 367 dev = __ip_tunnel_create(net, itn->fb_tunnel_dev->rtnl_link_ops, parms); 368 if (IS_ERR(dev)) 369 return ERR_CAST(dev); 370 371 dev->mtu = ip_tunnel_bind_dev(dev); 372 373 nt = netdev_priv(dev); 374 t_hlen = nt->hlen + sizeof(struct iphdr); 375 dev->min_mtu = ETH_MIN_MTU; 376 dev->max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen; 377 ip_tunnel_add(itn, nt); 378 return nt; 379 } 380 381 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb, 382 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst, 383 bool log_ecn_error) 384 { 385 struct pcpu_sw_netstats *tstats; 386 const struct iphdr *iph = ip_hdr(skb); 387 int err; 388 389 #ifdef CONFIG_NET_IPGRE_BROADCAST 390 if (ipv4_is_multicast(iph->daddr)) { 391 tunnel->dev->stats.multicast++; 392 skb->pkt_type = PACKET_BROADCAST; 393 } 394 #endif 395 396 if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) || 397 ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) { 398 tunnel->dev->stats.rx_crc_errors++; 399 tunnel->dev->stats.rx_errors++; 400 goto drop; 401 } 402 403 if (tunnel->parms.i_flags&TUNNEL_SEQ) { 404 if (!(tpi->flags&TUNNEL_SEQ) || 405 (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 406 tunnel->dev->stats.rx_fifo_errors++; 407 tunnel->dev->stats.rx_errors++; 408 goto drop; 409 } 410 tunnel->i_seqno = ntohl(tpi->seq) + 1; 411 } 412 413 skb_reset_network_header(skb); 414 415 err = IP_ECN_decapsulate(iph, skb); 416 if (unlikely(err)) { 417 if (log_ecn_error) 418 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", 419 &iph->saddr, iph->tos); 420 if (err > 1) { 421 ++tunnel->dev->stats.rx_frame_errors; 422 ++tunnel->dev->stats.rx_errors; 423 goto drop; 424 } 425 } 426 427 tstats = this_cpu_ptr(tunnel->dev->tstats); 428 u64_stats_update_begin(&tstats->syncp); 429 tstats->rx_packets++; 430 tstats->rx_bytes += skb->len; 431 u64_stats_update_end(&tstats->syncp); 432 433 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 434 435 if (tunnel->dev->type == ARPHRD_ETHER) { 436 skb->protocol = eth_type_trans(skb, tunnel->dev); 437 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 438 } else { 439 skb->dev = tunnel->dev; 440 } 441 442 if (tun_dst) 443 skb_dst_set(skb, (struct dst_entry *)tun_dst); 444 445 gro_cells_receive(&tunnel->gro_cells, skb); 446 return 0; 447 448 drop: 449 if (tun_dst) 450 dst_release((struct dst_entry *)tun_dst); 451 kfree_skb(skb); 452 return 0; 453 } 454 EXPORT_SYMBOL_GPL(ip_tunnel_rcv); 455 456 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops, 457 unsigned int num) 458 { 459 if (num >= MAX_IPTUN_ENCAP_OPS) 460 return -ERANGE; 461 462 return !cmpxchg((const struct ip_tunnel_encap_ops **) 463 &iptun_encaps[num], 464 NULL, ops) ? 0 : -1; 465 } 466 EXPORT_SYMBOL(ip_tunnel_encap_add_ops); 467 468 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops, 469 unsigned int num) 470 { 471 int ret; 472 473 if (num >= MAX_IPTUN_ENCAP_OPS) 474 return -ERANGE; 475 476 ret = (cmpxchg((const struct ip_tunnel_encap_ops **) 477 &iptun_encaps[num], 478 ops, NULL) == ops) ? 0 : -1; 479 480 synchronize_net(); 481 482 return ret; 483 } 484 EXPORT_SYMBOL(ip_tunnel_encap_del_ops); 485 486 int ip_tunnel_encap_setup(struct ip_tunnel *t, 487 struct ip_tunnel_encap *ipencap) 488 { 489 int hlen; 490 491 memset(&t->encap, 0, sizeof(t->encap)); 492 493 hlen = ip_encap_hlen(ipencap); 494 if (hlen < 0) 495 return hlen; 496 497 t->encap.type = ipencap->type; 498 t->encap.sport = ipencap->sport; 499 t->encap.dport = ipencap->dport; 500 t->encap.flags = ipencap->flags; 501 502 t->encap_hlen = hlen; 503 t->hlen = t->encap_hlen + t->tun_hlen; 504 505 return 0; 506 } 507 EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup); 508 509 static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, 510 struct rtable *rt, __be16 df, 511 const struct iphdr *inner_iph) 512 { 513 struct ip_tunnel *tunnel = netdev_priv(dev); 514 int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len; 515 int mtu; 516 517 if (df) 518 mtu = dst_mtu(&rt->dst) - dev->hard_header_len 519 - sizeof(struct iphdr) - tunnel->hlen; 520 else 521 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu; 522 523 skb_dst_update_pmtu(skb, mtu); 524 525 if (skb->protocol == htons(ETH_P_IP)) { 526 if (!skb_is_gso(skb) && 527 (inner_iph->frag_off & htons(IP_DF)) && 528 mtu < pkt_size) { 529 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 530 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); 531 return -E2BIG; 532 } 533 } 534 #if IS_ENABLED(CONFIG_IPV6) 535 else if (skb->protocol == htons(ETH_P_IPV6)) { 536 struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb); 537 538 if (rt6 && mtu < dst_mtu(skb_dst(skb)) && 539 mtu >= IPV6_MIN_MTU) { 540 if ((tunnel->parms.iph.daddr && 541 !ipv4_is_multicast(tunnel->parms.iph.daddr)) || 542 rt6->rt6i_dst.plen == 128) { 543 rt6->rt6i_flags |= RTF_MODIFIED; 544 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu); 545 } 546 } 547 548 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU && 549 mtu < pkt_size) { 550 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 551 return -E2BIG; 552 } 553 } 554 #endif 555 return 0; 556 } 557 558 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto) 559 { 560 struct ip_tunnel *tunnel = netdev_priv(dev); 561 u32 headroom = sizeof(struct iphdr); 562 struct ip_tunnel_info *tun_info; 563 const struct ip_tunnel_key *key; 564 const struct iphdr *inner_iph; 565 struct rtable *rt; 566 struct flowi4 fl4; 567 __be16 df = 0; 568 u8 tos, ttl; 569 570 tun_info = skb_tunnel_info(skb); 571 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 572 ip_tunnel_info_af(tun_info) != AF_INET)) 573 goto tx_error; 574 key = &tun_info->key; 575 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 576 inner_iph = (const struct iphdr *)skb_inner_network_header(skb); 577 tos = key->tos; 578 if (tos == 1) { 579 if (skb->protocol == htons(ETH_P_IP)) 580 tos = inner_iph->tos; 581 else if (skb->protocol == htons(ETH_P_IPV6)) 582 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); 583 } 584 init_tunnel_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 0, 585 RT_TOS(tos), tunnel->parms.link, tunnel->fwmark); 586 if (tunnel->encap.type != TUNNEL_ENCAP_NONE) 587 goto tx_error; 588 rt = ip_route_output_key(tunnel->net, &fl4); 589 if (IS_ERR(rt)) { 590 dev->stats.tx_carrier_errors++; 591 goto tx_error; 592 } 593 if (rt->dst.dev == dev) { 594 ip_rt_put(rt); 595 dev->stats.collisions++; 596 goto tx_error; 597 } 598 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); 599 ttl = key->ttl; 600 if (ttl == 0) { 601 if (skb->protocol == htons(ETH_P_IP)) 602 ttl = inner_iph->ttl; 603 else if (skb->protocol == htons(ETH_P_IPV6)) 604 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; 605 else 606 ttl = ip4_dst_hoplimit(&rt->dst); 607 } 608 if (key->tun_flags & TUNNEL_DONT_FRAGMENT) 609 df = htons(IP_DF); 610 else if (skb->protocol == htons(ETH_P_IP)) 611 df = inner_iph->frag_off & htons(IP_DF); 612 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; 613 if (headroom > dev->needed_headroom) 614 dev->needed_headroom = headroom; 615 616 if (skb_cow_head(skb, dev->needed_headroom)) { 617 ip_rt_put(rt); 618 goto tx_dropped; 619 } 620 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl, 621 df, !net_eq(tunnel->net, dev_net(dev))); 622 return; 623 tx_error: 624 dev->stats.tx_errors++; 625 goto kfree; 626 tx_dropped: 627 dev->stats.tx_dropped++; 628 kfree: 629 kfree_skb(skb); 630 } 631 EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit); 632 633 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 634 const struct iphdr *tnl_params, u8 protocol) 635 { 636 struct ip_tunnel *tunnel = netdev_priv(dev); 637 const struct iphdr *inner_iph; 638 struct flowi4 fl4; 639 u8 tos, ttl; 640 __be16 df; 641 struct rtable *rt; /* Route to the other host */ 642 unsigned int max_headroom; /* The extra header space needed */ 643 __be32 dst; 644 bool connected; 645 646 inner_iph = (const struct iphdr *)skb_inner_network_header(skb); 647 connected = (tunnel->parms.iph.daddr != 0); 648 649 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 650 651 dst = tnl_params->daddr; 652 if (dst == 0) { 653 /* NBMA tunnel */ 654 655 if (!skb_dst(skb)) { 656 dev->stats.tx_fifo_errors++; 657 goto tx_error; 658 } 659 660 if (skb->protocol == htons(ETH_P_IP)) { 661 rt = skb_rtable(skb); 662 dst = rt_nexthop(rt, inner_iph->daddr); 663 } 664 #if IS_ENABLED(CONFIG_IPV6) 665 else if (skb->protocol == htons(ETH_P_IPV6)) { 666 const struct in6_addr *addr6; 667 struct neighbour *neigh; 668 bool do_tx_error_icmp; 669 int addr_type; 670 671 neigh = dst_neigh_lookup(skb_dst(skb), 672 &ipv6_hdr(skb)->daddr); 673 if (!neigh) 674 goto tx_error; 675 676 addr6 = (const struct in6_addr *)&neigh->primary_key; 677 addr_type = ipv6_addr_type(addr6); 678 679 if (addr_type == IPV6_ADDR_ANY) { 680 addr6 = &ipv6_hdr(skb)->daddr; 681 addr_type = ipv6_addr_type(addr6); 682 } 683 684 if ((addr_type & IPV6_ADDR_COMPATv4) == 0) 685 do_tx_error_icmp = true; 686 else { 687 do_tx_error_icmp = false; 688 dst = addr6->s6_addr32[3]; 689 } 690 neigh_release(neigh); 691 if (do_tx_error_icmp) 692 goto tx_error_icmp; 693 } 694 #endif 695 else 696 goto tx_error; 697 698 connected = false; 699 } 700 701 tos = tnl_params->tos; 702 if (tos & 0x1) { 703 tos &= ~0x1; 704 if (skb->protocol == htons(ETH_P_IP)) { 705 tos = inner_iph->tos; 706 connected = false; 707 } else if (skb->protocol == htons(ETH_P_IPV6)) { 708 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); 709 connected = false; 710 } 711 } 712 713 if (tunnel->fwmark) { 714 init_tunnel_flow(&fl4, protocol, dst, tnl_params->saddr, 715 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link, 716 tunnel->fwmark); 717 } 718 else { 719 init_tunnel_flow(&fl4, protocol, dst, tnl_params->saddr, 720 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link, 721 skb->mark); 722 } 723 724 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) 725 goto tx_error; 726 727 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr) : 728 NULL; 729 730 if (!rt) { 731 rt = ip_route_output_key(tunnel->net, &fl4); 732 733 if (IS_ERR(rt)) { 734 dev->stats.tx_carrier_errors++; 735 goto tx_error; 736 } 737 if (connected) 738 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, 739 fl4.saddr); 740 } 741 742 if (rt->dst.dev == dev) { 743 ip_rt_put(rt); 744 dev->stats.collisions++; 745 goto tx_error; 746 } 747 748 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) { 749 ip_rt_put(rt); 750 goto tx_error; 751 } 752 753 if (tunnel->err_count > 0) { 754 if (time_before(jiffies, 755 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 756 tunnel->err_count--; 757 758 dst_link_failure(skb); 759 } else 760 tunnel->err_count = 0; 761 } 762 763 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); 764 ttl = tnl_params->ttl; 765 if (ttl == 0) { 766 if (skb->protocol == htons(ETH_P_IP)) 767 ttl = inner_iph->ttl; 768 #if IS_ENABLED(CONFIG_IPV6) 769 else if (skb->protocol == htons(ETH_P_IPV6)) 770 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; 771 #endif 772 else 773 ttl = ip4_dst_hoplimit(&rt->dst); 774 } 775 776 df = tnl_params->frag_off; 777 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df) 778 df |= (inner_iph->frag_off&htons(IP_DF)); 779 780 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) 781 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap); 782 if (max_headroom > dev->needed_headroom) 783 dev->needed_headroom = max_headroom; 784 785 if (skb_cow_head(skb, dev->needed_headroom)) { 786 ip_rt_put(rt); 787 dev->stats.tx_dropped++; 788 kfree_skb(skb); 789 return; 790 } 791 792 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, 793 df, !net_eq(tunnel->net, dev_net(dev))); 794 return; 795 796 #if IS_ENABLED(CONFIG_IPV6) 797 tx_error_icmp: 798 dst_link_failure(skb); 799 #endif 800 tx_error: 801 dev->stats.tx_errors++; 802 kfree_skb(skb); 803 } 804 EXPORT_SYMBOL_GPL(ip_tunnel_xmit); 805 806 static void ip_tunnel_update(struct ip_tunnel_net *itn, 807 struct ip_tunnel *t, 808 struct net_device *dev, 809 struct ip_tunnel_parm *p, 810 bool set_mtu, 811 __u32 fwmark) 812 { 813 ip_tunnel_del(itn, t); 814 t->parms.iph.saddr = p->iph.saddr; 815 t->parms.iph.daddr = p->iph.daddr; 816 t->parms.i_key = p->i_key; 817 t->parms.o_key = p->o_key; 818 if (dev->type != ARPHRD_ETHER) { 819 memcpy(dev->dev_addr, &p->iph.saddr, 4); 820 memcpy(dev->broadcast, &p->iph.daddr, 4); 821 } 822 ip_tunnel_add(itn, t); 823 824 t->parms.iph.ttl = p->iph.ttl; 825 t->parms.iph.tos = p->iph.tos; 826 t->parms.iph.frag_off = p->iph.frag_off; 827 828 if (t->parms.link != p->link || t->fwmark != fwmark) { 829 int mtu; 830 831 t->parms.link = p->link; 832 t->fwmark = fwmark; 833 mtu = ip_tunnel_bind_dev(dev); 834 if (set_mtu) 835 dev->mtu = mtu; 836 } 837 dst_cache_reset(&t->dst_cache); 838 netdev_state_change(dev); 839 } 840 841 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) 842 { 843 int err = 0; 844 struct ip_tunnel *t = netdev_priv(dev); 845 struct net *net = t->net; 846 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id); 847 848 BUG_ON(!itn->fb_tunnel_dev); 849 switch (cmd) { 850 case SIOCGETTUNNEL: 851 if (dev == itn->fb_tunnel_dev) { 852 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 853 if (!t) 854 t = netdev_priv(dev); 855 } 856 memcpy(p, &t->parms, sizeof(*p)); 857 break; 858 859 case SIOCADDTUNNEL: 860 case SIOCCHGTUNNEL: 861 err = -EPERM; 862 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 863 goto done; 864 if (p->iph.ttl) 865 p->iph.frag_off |= htons(IP_DF); 866 if (!(p->i_flags & VTI_ISVTI)) { 867 if (!(p->i_flags & TUNNEL_KEY)) 868 p->i_key = 0; 869 if (!(p->o_flags & TUNNEL_KEY)) 870 p->o_key = 0; 871 } 872 873 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 874 875 if (cmd == SIOCADDTUNNEL) { 876 if (!t) { 877 t = ip_tunnel_create(net, itn, p); 878 err = PTR_ERR_OR_ZERO(t); 879 break; 880 } 881 882 err = -EEXIST; 883 break; 884 } 885 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 886 if (t) { 887 if (t->dev != dev) { 888 err = -EEXIST; 889 break; 890 } 891 } else { 892 unsigned int nflags = 0; 893 894 if (ipv4_is_multicast(p->iph.daddr)) 895 nflags = IFF_BROADCAST; 896 else if (p->iph.daddr) 897 nflags = IFF_POINTOPOINT; 898 899 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) { 900 err = -EINVAL; 901 break; 902 } 903 904 t = netdev_priv(dev); 905 } 906 } 907 908 if (t) { 909 err = 0; 910 ip_tunnel_update(itn, t, dev, p, true, 0); 911 } else { 912 err = -ENOENT; 913 } 914 break; 915 916 case SIOCDELTUNNEL: 917 err = -EPERM; 918 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 919 goto done; 920 921 if (dev == itn->fb_tunnel_dev) { 922 err = -ENOENT; 923 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 924 if (!t) 925 goto done; 926 err = -EPERM; 927 if (t == netdev_priv(itn->fb_tunnel_dev)) 928 goto done; 929 dev = t->dev; 930 } 931 unregister_netdevice(dev); 932 err = 0; 933 break; 934 935 default: 936 err = -EINVAL; 937 } 938 939 done: 940 return err; 941 } 942 EXPORT_SYMBOL_GPL(ip_tunnel_ioctl); 943 944 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict) 945 { 946 struct ip_tunnel *tunnel = netdev_priv(dev); 947 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 948 int max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen; 949 950 if (new_mtu < ETH_MIN_MTU) 951 return -EINVAL; 952 953 if (new_mtu > max_mtu) { 954 if (strict) 955 return -EINVAL; 956 957 new_mtu = max_mtu; 958 } 959 960 dev->mtu = new_mtu; 961 return 0; 962 } 963 EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu); 964 965 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu) 966 { 967 return __ip_tunnel_change_mtu(dev, new_mtu, true); 968 } 969 EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu); 970 971 static void ip_tunnel_dev_free(struct net_device *dev) 972 { 973 struct ip_tunnel *tunnel = netdev_priv(dev); 974 975 gro_cells_destroy(&tunnel->gro_cells); 976 dst_cache_destroy(&tunnel->dst_cache); 977 free_percpu(dev->tstats); 978 } 979 980 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head) 981 { 982 struct ip_tunnel *tunnel = netdev_priv(dev); 983 struct ip_tunnel_net *itn; 984 985 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id); 986 987 if (itn->fb_tunnel_dev != dev) { 988 ip_tunnel_del(itn, netdev_priv(dev)); 989 unregister_netdevice_queue(dev, head); 990 } 991 } 992 EXPORT_SYMBOL_GPL(ip_tunnel_dellink); 993 994 struct net *ip_tunnel_get_link_net(const struct net_device *dev) 995 { 996 struct ip_tunnel *tunnel = netdev_priv(dev); 997 998 return tunnel->net; 999 } 1000 EXPORT_SYMBOL(ip_tunnel_get_link_net); 1001 1002 int ip_tunnel_get_iflink(const struct net_device *dev) 1003 { 1004 struct ip_tunnel *tunnel = netdev_priv(dev); 1005 1006 return tunnel->parms.link; 1007 } 1008 EXPORT_SYMBOL(ip_tunnel_get_iflink); 1009 1010 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, 1011 struct rtnl_link_ops *ops, char *devname) 1012 { 1013 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id); 1014 struct ip_tunnel_parm parms; 1015 unsigned int i; 1016 1017 for (i = 0; i < IP_TNL_HASH_SIZE; i++) 1018 INIT_HLIST_HEAD(&itn->tunnels[i]); 1019 1020 if (!ops) { 1021 itn->fb_tunnel_dev = NULL; 1022 return 0; 1023 } 1024 1025 memset(&parms, 0, sizeof(parms)); 1026 if (devname) 1027 strlcpy(parms.name, devname, IFNAMSIZ); 1028 1029 rtnl_lock(); 1030 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms); 1031 /* FB netdevice is special: we have one, and only one per netns. 1032 * Allowing to move it to another netns is clearly unsafe. 1033 */ 1034 if (!IS_ERR(itn->fb_tunnel_dev)) { 1035 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1036 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev); 1037 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev)); 1038 } 1039 rtnl_unlock(); 1040 1041 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev); 1042 } 1043 EXPORT_SYMBOL_GPL(ip_tunnel_init_net); 1044 1045 static void ip_tunnel_destroy(struct ip_tunnel_net *itn, struct list_head *head, 1046 struct rtnl_link_ops *ops) 1047 { 1048 struct net *net = dev_net(itn->fb_tunnel_dev); 1049 struct net_device *dev, *aux; 1050 int h; 1051 1052 for_each_netdev_safe(net, dev, aux) 1053 if (dev->rtnl_link_ops == ops) 1054 unregister_netdevice_queue(dev, head); 1055 1056 for (h = 0; h < IP_TNL_HASH_SIZE; h++) { 1057 struct ip_tunnel *t; 1058 struct hlist_node *n; 1059 struct hlist_head *thead = &itn->tunnels[h]; 1060 1061 hlist_for_each_entry_safe(t, n, thead, hash_node) 1062 /* If dev is in the same netns, it has already 1063 * been added to the list by the previous loop. 1064 */ 1065 if (!net_eq(dev_net(t->dev), net)) 1066 unregister_netdevice_queue(t->dev, head); 1067 } 1068 } 1069 1070 void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id, 1071 struct rtnl_link_ops *ops) 1072 { 1073 struct ip_tunnel_net *itn; 1074 struct net *net; 1075 LIST_HEAD(list); 1076 1077 rtnl_lock(); 1078 list_for_each_entry(net, net_list, exit_list) { 1079 itn = net_generic(net, id); 1080 ip_tunnel_destroy(itn, &list, ops); 1081 } 1082 unregister_netdevice_many(&list); 1083 rtnl_unlock(); 1084 } 1085 EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets); 1086 1087 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 1088 struct ip_tunnel_parm *p, __u32 fwmark) 1089 { 1090 struct ip_tunnel *nt; 1091 struct net *net = dev_net(dev); 1092 struct ip_tunnel_net *itn; 1093 int mtu; 1094 int err; 1095 1096 nt = netdev_priv(dev); 1097 itn = net_generic(net, nt->ip_tnl_net_id); 1098 1099 if (nt->collect_md) { 1100 if (rtnl_dereference(itn->collect_md_tun)) 1101 return -EEXIST; 1102 } else { 1103 if (ip_tunnel_find(itn, p, dev->type)) 1104 return -EEXIST; 1105 } 1106 1107 nt->net = net; 1108 nt->parms = *p; 1109 nt->fwmark = fwmark; 1110 err = register_netdevice(dev); 1111 if (err) 1112 goto out; 1113 1114 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1115 eth_hw_addr_random(dev); 1116 1117 mtu = ip_tunnel_bind_dev(dev); 1118 if (!tb[IFLA_MTU]) 1119 dev->mtu = mtu; 1120 1121 ip_tunnel_add(itn, nt); 1122 out: 1123 return err; 1124 } 1125 EXPORT_SYMBOL_GPL(ip_tunnel_newlink); 1126 1127 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], 1128 struct ip_tunnel_parm *p, __u32 fwmark) 1129 { 1130 struct ip_tunnel *t; 1131 struct ip_tunnel *tunnel = netdev_priv(dev); 1132 struct net *net = tunnel->net; 1133 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id); 1134 1135 if (dev == itn->fb_tunnel_dev) 1136 return -EINVAL; 1137 1138 t = ip_tunnel_find(itn, p, dev->type); 1139 1140 if (t) { 1141 if (t->dev != dev) 1142 return -EEXIST; 1143 } else { 1144 t = tunnel; 1145 1146 if (dev->type != ARPHRD_ETHER) { 1147 unsigned int nflags = 0; 1148 1149 if (ipv4_is_multicast(p->iph.daddr)) 1150 nflags = IFF_BROADCAST; 1151 else if (p->iph.daddr) 1152 nflags = IFF_POINTOPOINT; 1153 1154 if ((dev->flags ^ nflags) & 1155 (IFF_POINTOPOINT | IFF_BROADCAST)) 1156 return -EINVAL; 1157 } 1158 } 1159 1160 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark); 1161 return 0; 1162 } 1163 EXPORT_SYMBOL_GPL(ip_tunnel_changelink); 1164 1165 int ip_tunnel_init(struct net_device *dev) 1166 { 1167 struct ip_tunnel *tunnel = netdev_priv(dev); 1168 struct iphdr *iph = &tunnel->parms.iph; 1169 int err; 1170 1171 dev->needs_free_netdev = true; 1172 dev->priv_destructor = ip_tunnel_dev_free; 1173 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1174 if (!dev->tstats) 1175 return -ENOMEM; 1176 1177 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1178 if (err) { 1179 free_percpu(dev->tstats); 1180 return err; 1181 } 1182 1183 err = gro_cells_init(&tunnel->gro_cells, dev); 1184 if (err) { 1185 dst_cache_destroy(&tunnel->dst_cache); 1186 free_percpu(dev->tstats); 1187 return err; 1188 } 1189 1190 tunnel->dev = dev; 1191 tunnel->net = dev_net(dev); 1192 strcpy(tunnel->parms.name, dev->name); 1193 iph->version = 4; 1194 iph->ihl = 5; 1195 1196 if (tunnel->collect_md) { 1197 dev->features |= NETIF_F_NETNS_LOCAL; 1198 netif_keep_dst(dev); 1199 } 1200 return 0; 1201 } 1202 EXPORT_SYMBOL_GPL(ip_tunnel_init); 1203 1204 void ip_tunnel_uninit(struct net_device *dev) 1205 { 1206 struct ip_tunnel *tunnel = netdev_priv(dev); 1207 struct net *net = tunnel->net; 1208 struct ip_tunnel_net *itn; 1209 1210 itn = net_generic(net, tunnel->ip_tnl_net_id); 1211 /* fb_tunnel_dev will be unregisted in net-exit call. */ 1212 if (itn->fb_tunnel_dev != dev) 1213 ip_tunnel_del(itn, netdev_priv(dev)); 1214 1215 dst_cache_reset(&tunnel->dst_cache); 1216 } 1217 EXPORT_SYMBOL_GPL(ip_tunnel_uninit); 1218 1219 /* Do least required initialization, rest of init is done in tunnel_init call */ 1220 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id) 1221 { 1222 struct ip_tunnel *tunnel = netdev_priv(dev); 1223 tunnel->ip_tnl_net_id = net_id; 1224 } 1225 EXPORT_SYMBOL_GPL(ip_tunnel_setup); 1226 1227 MODULE_LICENSE("GPL"); 1228