1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2013 Nicira, Inc. 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/capability.h> 9 #include <linux/module.h> 10 #include <linux/types.h> 11 #include <linux/kernel.h> 12 #include <linux/slab.h> 13 #include <linux/uaccess.h> 14 #include <linux/skbuff.h> 15 #include <linux/netdevice.h> 16 #include <linux/in.h> 17 #include <linux/tcp.h> 18 #include <linux/udp.h> 19 #include <linux/if_arp.h> 20 #include <linux/init.h> 21 #include <linux/in6.h> 22 #include <linux/inetdevice.h> 23 #include <linux/igmp.h> 24 #include <linux/netfilter_ipv4.h> 25 #include <linux/etherdevice.h> 26 #include <linux/if_ether.h> 27 #include <linux/if_vlan.h> 28 #include <linux/rculist.h> 29 #include <linux/err.h> 30 31 #include <net/sock.h> 32 #include <net/ip.h> 33 #include <net/icmp.h> 34 #include <net/protocol.h> 35 #include <net/ip_tunnels.h> 36 #include <net/arp.h> 37 #include <net/checksum.h> 38 #include <net/dsfield.h> 39 #include <net/inet_ecn.h> 40 #include <net/xfrm.h> 41 #include <net/net_namespace.h> 42 #include <net/netns/generic.h> 43 #include <net/rtnetlink.h> 44 #include <net/udp.h> 45 #include <net/dst_metadata.h> 46 47 #if IS_ENABLED(CONFIG_IPV6) 48 #include <net/ipv6.h> 49 #include <net/ip6_fib.h> 50 #include <net/ip6_route.h> 51 #endif 52 53 static unsigned int ip_tunnel_hash(__be32 key, __be32 remote) 54 { 55 return hash_32((__force u32)key ^ (__force u32)remote, 56 IP_TNL_HASH_BITS); 57 } 58 59 static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p, 60 __be16 flags, __be32 key) 61 { 62 if (p->i_flags & TUNNEL_KEY) { 63 if (flags & TUNNEL_KEY) 64 return key == p->i_key; 65 else 66 /* key expected, none present */ 67 return false; 68 } else 69 return !(flags & TUNNEL_KEY); 70 } 71 72 /* Fallback tunnel: no source, no destination, no key, no options 73 74 Tunnel hash table: 75 We require exact key match i.e. if a key is present in packet 76 it will match only tunnel with the same key; if it is not present, 77 it will match only keyless tunnel. 78 79 All keysless packets, if not matched configured keyless tunnels 80 will match fallback tunnel. 81 Given src, dst and key, find appropriate for input tunnel. 82 */ 83 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn, 84 int link, __be16 flags, 85 __be32 remote, __be32 local, 86 __be32 key) 87 { 88 struct ip_tunnel *t, *cand = NULL; 89 struct hlist_head *head; 90 struct net_device *ndev; 91 unsigned int hash; 92 93 hash = ip_tunnel_hash(key, remote); 94 head = &itn->tunnels[hash]; 95 96 hlist_for_each_entry_rcu(t, head, hash_node) { 97 if (local != t->parms.iph.saddr || 98 remote != t->parms.iph.daddr || 99 !(t->dev->flags & IFF_UP)) 100 continue; 101 102 if (!ip_tunnel_key_match(&t->parms, flags, key)) 103 continue; 104 105 if (t->parms.link == link) 106 return t; 107 else 108 cand = t; 109 } 110 111 hlist_for_each_entry_rcu(t, head, hash_node) { 112 if (remote != t->parms.iph.daddr || 113 t->parms.iph.saddr != 0 || 114 !(t->dev->flags & IFF_UP)) 115 continue; 116 117 if (!ip_tunnel_key_match(&t->parms, flags, key)) 118 continue; 119 120 if (t->parms.link == link) 121 return t; 122 else if (!cand) 123 cand = t; 124 } 125 126 hash = ip_tunnel_hash(key, 0); 127 head = &itn->tunnels[hash]; 128 129 hlist_for_each_entry_rcu(t, head, hash_node) { 130 if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) && 131 (local != t->parms.iph.daddr || !ipv4_is_multicast(local))) 132 continue; 133 134 if (!(t->dev->flags & IFF_UP)) 135 continue; 136 137 if (!ip_tunnel_key_match(&t->parms, flags, key)) 138 continue; 139 140 if (t->parms.link == link) 141 return t; 142 else if (!cand) 143 cand = t; 144 } 145 146 hlist_for_each_entry_rcu(t, head, hash_node) { 147 if ((!(flags & TUNNEL_NO_KEY) && t->parms.i_key != key) || 148 t->parms.iph.saddr != 0 || 149 t->parms.iph.daddr != 0 || 150 !(t->dev->flags & IFF_UP)) 151 continue; 152 153 if (t->parms.link == link) 154 return t; 155 else if (!cand) 156 cand = t; 157 } 158 159 if (cand) 160 return cand; 161 162 t = rcu_dereference(itn->collect_md_tun); 163 if (t && t->dev->flags & IFF_UP) 164 return t; 165 166 ndev = READ_ONCE(itn->fb_tunnel_dev); 167 if (ndev && ndev->flags & IFF_UP) 168 return netdev_priv(ndev); 169 170 return NULL; 171 } 172 EXPORT_SYMBOL_GPL(ip_tunnel_lookup); 173 174 static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn, 175 struct ip_tunnel_parm *parms) 176 { 177 unsigned int h; 178 __be32 remote; 179 __be32 i_key = parms->i_key; 180 181 if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr)) 182 remote = parms->iph.daddr; 183 else 184 remote = 0; 185 186 if (!(parms->i_flags & TUNNEL_KEY) && (parms->i_flags & VTI_ISVTI)) 187 i_key = 0; 188 189 h = ip_tunnel_hash(i_key, remote); 190 return &itn->tunnels[h]; 191 } 192 193 static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t) 194 { 195 struct hlist_head *head = ip_bucket(itn, &t->parms); 196 197 if (t->collect_md) 198 rcu_assign_pointer(itn->collect_md_tun, t); 199 hlist_add_head_rcu(&t->hash_node, head); 200 } 201 202 static void ip_tunnel_del(struct ip_tunnel_net *itn, struct ip_tunnel *t) 203 { 204 if (t->collect_md) 205 rcu_assign_pointer(itn->collect_md_tun, NULL); 206 hlist_del_init_rcu(&t->hash_node); 207 } 208 209 static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn, 210 struct ip_tunnel_parm *parms, 211 int type) 212 { 213 __be32 remote = parms->iph.daddr; 214 __be32 local = parms->iph.saddr; 215 __be32 key = parms->i_key; 216 __be16 flags = parms->i_flags; 217 int link = parms->link; 218 struct ip_tunnel *t = NULL; 219 struct hlist_head *head = ip_bucket(itn, parms); 220 221 hlist_for_each_entry_rcu(t, head, hash_node) { 222 if (local == t->parms.iph.saddr && 223 remote == t->parms.iph.daddr && 224 link == t->parms.link && 225 type == t->dev->type && 226 ip_tunnel_key_match(&t->parms, flags, key)) 227 break; 228 } 229 return t; 230 } 231 232 static struct net_device *__ip_tunnel_create(struct net *net, 233 const struct rtnl_link_ops *ops, 234 struct ip_tunnel_parm *parms) 235 { 236 int err; 237 struct ip_tunnel *tunnel; 238 struct net_device *dev; 239 char name[IFNAMSIZ]; 240 241 err = -E2BIG; 242 if (parms->name[0]) { 243 if (!dev_valid_name(parms->name)) 244 goto failed; 245 strlcpy(name, parms->name, IFNAMSIZ); 246 } else { 247 if (strlen(ops->kind) > (IFNAMSIZ - 3)) 248 goto failed; 249 strcpy(name, ops->kind); 250 strcat(name, "%d"); 251 } 252 253 ASSERT_RTNL(); 254 dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup); 255 if (!dev) { 256 err = -ENOMEM; 257 goto failed; 258 } 259 dev_net_set(dev, net); 260 261 dev->rtnl_link_ops = ops; 262 263 tunnel = netdev_priv(dev); 264 tunnel->parms = *parms; 265 tunnel->net = net; 266 267 err = register_netdevice(dev); 268 if (err) 269 goto failed_free; 270 271 return dev; 272 273 failed_free: 274 free_netdev(dev); 275 failed: 276 return ERR_PTR(err); 277 } 278 279 static int ip_tunnel_bind_dev(struct net_device *dev) 280 { 281 struct net_device *tdev = NULL; 282 struct ip_tunnel *tunnel = netdev_priv(dev); 283 const struct iphdr *iph; 284 int hlen = LL_MAX_HEADER; 285 int mtu = ETH_DATA_LEN; 286 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 287 288 iph = &tunnel->parms.iph; 289 290 /* Guess output device to choose reasonable mtu and needed_headroom */ 291 if (iph->daddr) { 292 struct flowi4 fl4; 293 struct rtable *rt; 294 295 ip_tunnel_init_flow(&fl4, iph->protocol, iph->daddr, 296 iph->saddr, tunnel->parms.o_key, 297 RT_TOS(iph->tos), tunnel->parms.link, 298 tunnel->fwmark, 0); 299 rt = ip_route_output_key(tunnel->net, &fl4); 300 301 if (!IS_ERR(rt)) { 302 tdev = rt->dst.dev; 303 ip_rt_put(rt); 304 } 305 if (dev->type != ARPHRD_ETHER) 306 dev->flags |= IFF_POINTOPOINT; 307 308 dst_cache_reset(&tunnel->dst_cache); 309 } 310 311 if (!tdev && tunnel->parms.link) 312 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); 313 314 if (tdev) { 315 hlen = tdev->hard_header_len + tdev->needed_headroom; 316 mtu = min(tdev->mtu, IP_MAX_MTU); 317 } 318 319 dev->needed_headroom = t_hlen + hlen; 320 mtu -= (dev->hard_header_len + t_hlen); 321 322 if (mtu < IPV4_MIN_MTU) 323 mtu = IPV4_MIN_MTU; 324 325 return mtu; 326 } 327 328 static struct ip_tunnel *ip_tunnel_create(struct net *net, 329 struct ip_tunnel_net *itn, 330 struct ip_tunnel_parm *parms) 331 { 332 struct ip_tunnel *nt; 333 struct net_device *dev; 334 int t_hlen; 335 int mtu; 336 int err; 337 338 dev = __ip_tunnel_create(net, itn->rtnl_link_ops, parms); 339 if (IS_ERR(dev)) 340 return ERR_CAST(dev); 341 342 mtu = ip_tunnel_bind_dev(dev); 343 err = dev_set_mtu(dev, mtu); 344 if (err) 345 goto err_dev_set_mtu; 346 347 nt = netdev_priv(dev); 348 t_hlen = nt->hlen + sizeof(struct iphdr); 349 dev->min_mtu = ETH_MIN_MTU; 350 dev->max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen; 351 ip_tunnel_add(itn, nt); 352 return nt; 353 354 err_dev_set_mtu: 355 unregister_netdevice(dev); 356 return ERR_PTR(err); 357 } 358 359 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb, 360 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst, 361 bool log_ecn_error) 362 { 363 const struct iphdr *iph = ip_hdr(skb); 364 int err; 365 366 #ifdef CONFIG_NET_IPGRE_BROADCAST 367 if (ipv4_is_multicast(iph->daddr)) { 368 tunnel->dev->stats.multicast++; 369 skb->pkt_type = PACKET_BROADCAST; 370 } 371 #endif 372 373 if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) || 374 ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) { 375 tunnel->dev->stats.rx_crc_errors++; 376 tunnel->dev->stats.rx_errors++; 377 goto drop; 378 } 379 380 if (tunnel->parms.i_flags&TUNNEL_SEQ) { 381 if (!(tpi->flags&TUNNEL_SEQ) || 382 (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { 383 tunnel->dev->stats.rx_fifo_errors++; 384 tunnel->dev->stats.rx_errors++; 385 goto drop; 386 } 387 tunnel->i_seqno = ntohl(tpi->seq) + 1; 388 } 389 390 skb_reset_network_header(skb); 391 392 err = IP_ECN_decapsulate(iph, skb); 393 if (unlikely(err)) { 394 if (log_ecn_error) 395 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", 396 &iph->saddr, iph->tos); 397 if (err > 1) { 398 ++tunnel->dev->stats.rx_frame_errors; 399 ++tunnel->dev->stats.rx_errors; 400 goto drop; 401 } 402 } 403 404 dev_sw_netstats_rx_add(tunnel->dev, skb->len); 405 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); 406 407 if (tunnel->dev->type == ARPHRD_ETHER) { 408 skb->protocol = eth_type_trans(skb, tunnel->dev); 409 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 410 } else { 411 skb->dev = tunnel->dev; 412 } 413 414 if (tun_dst) 415 skb_dst_set(skb, (struct dst_entry *)tun_dst); 416 417 gro_cells_receive(&tunnel->gro_cells, skb); 418 return 0; 419 420 drop: 421 if (tun_dst) 422 dst_release((struct dst_entry *)tun_dst); 423 kfree_skb(skb); 424 return 0; 425 } 426 EXPORT_SYMBOL_GPL(ip_tunnel_rcv); 427 428 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops, 429 unsigned int num) 430 { 431 if (num >= MAX_IPTUN_ENCAP_OPS) 432 return -ERANGE; 433 434 return !cmpxchg((const struct ip_tunnel_encap_ops **) 435 &iptun_encaps[num], 436 NULL, ops) ? 0 : -1; 437 } 438 EXPORT_SYMBOL(ip_tunnel_encap_add_ops); 439 440 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops, 441 unsigned int num) 442 { 443 int ret; 444 445 if (num >= MAX_IPTUN_ENCAP_OPS) 446 return -ERANGE; 447 448 ret = (cmpxchg((const struct ip_tunnel_encap_ops **) 449 &iptun_encaps[num], 450 ops, NULL) == ops) ? 0 : -1; 451 452 synchronize_net(); 453 454 return ret; 455 } 456 EXPORT_SYMBOL(ip_tunnel_encap_del_ops); 457 458 int ip_tunnel_encap_setup(struct ip_tunnel *t, 459 struct ip_tunnel_encap *ipencap) 460 { 461 int hlen; 462 463 memset(&t->encap, 0, sizeof(t->encap)); 464 465 hlen = ip_encap_hlen(ipencap); 466 if (hlen < 0) 467 return hlen; 468 469 t->encap.type = ipencap->type; 470 t->encap.sport = ipencap->sport; 471 t->encap.dport = ipencap->dport; 472 t->encap.flags = ipencap->flags; 473 474 t->encap_hlen = hlen; 475 t->hlen = t->encap_hlen + t->tun_hlen; 476 477 return 0; 478 } 479 EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup); 480 481 static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, 482 struct rtable *rt, __be16 df, 483 const struct iphdr *inner_iph, 484 int tunnel_hlen, __be32 dst, bool md) 485 { 486 struct ip_tunnel *tunnel = netdev_priv(dev); 487 int pkt_size; 488 int mtu; 489 490 tunnel_hlen = md ? tunnel_hlen : tunnel->hlen; 491 pkt_size = skb->len - tunnel_hlen - dev->hard_header_len; 492 493 if (df) 494 mtu = dst_mtu(&rt->dst) - dev->hard_header_len 495 - sizeof(struct iphdr) - tunnel_hlen; 496 else 497 mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu; 498 499 if (skb_valid_dst(skb)) 500 skb_dst_update_pmtu_no_confirm(skb, mtu); 501 502 if (skb->protocol == htons(ETH_P_IP)) { 503 if (!skb_is_gso(skb) && 504 (inner_iph->frag_off & htons(IP_DF)) && 505 mtu < pkt_size) { 506 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 507 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); 508 return -E2BIG; 509 } 510 } 511 #if IS_ENABLED(CONFIG_IPV6) 512 else if (skb->protocol == htons(ETH_P_IPV6)) { 513 struct rt6_info *rt6; 514 __be32 daddr; 515 516 rt6 = skb_valid_dst(skb) ? (struct rt6_info *)skb_dst(skb) : 517 NULL; 518 daddr = md ? dst : tunnel->parms.iph.daddr; 519 520 if (rt6 && mtu < dst_mtu(skb_dst(skb)) && 521 mtu >= IPV6_MIN_MTU) { 522 if ((daddr && !ipv4_is_multicast(daddr)) || 523 rt6->rt6i_dst.plen == 128) { 524 rt6->rt6i_flags |= RTF_MODIFIED; 525 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu); 526 } 527 } 528 529 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU && 530 mtu < pkt_size) { 531 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 532 return -E2BIG; 533 } 534 } 535 #endif 536 return 0; 537 } 538 539 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 540 u8 proto, int tunnel_hlen) 541 { 542 struct ip_tunnel *tunnel = netdev_priv(dev); 543 u32 headroom = sizeof(struct iphdr); 544 struct ip_tunnel_info *tun_info; 545 const struct ip_tunnel_key *key; 546 const struct iphdr *inner_iph; 547 struct rtable *rt = NULL; 548 struct flowi4 fl4; 549 __be16 df = 0; 550 u8 tos, ttl; 551 bool use_cache; 552 553 tun_info = skb_tunnel_info(skb); 554 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 555 ip_tunnel_info_af(tun_info) != AF_INET)) 556 goto tx_error; 557 key = &tun_info->key; 558 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 559 inner_iph = (const struct iphdr *)skb_inner_network_header(skb); 560 tos = key->tos; 561 if (tos == 1) { 562 if (skb->protocol == htons(ETH_P_IP)) 563 tos = inner_iph->tos; 564 else if (skb->protocol == htons(ETH_P_IPV6)) 565 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); 566 } 567 ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 568 tunnel_id_to_key32(key->tun_id), RT_TOS(tos), 569 0, skb->mark, skb_get_hash(skb)); 570 if (tunnel->encap.type != TUNNEL_ENCAP_NONE) 571 goto tx_error; 572 573 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info); 574 if (use_cache) 575 rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl4.saddr); 576 if (!rt) { 577 rt = ip_route_output_key(tunnel->net, &fl4); 578 if (IS_ERR(rt)) { 579 dev->stats.tx_carrier_errors++; 580 goto tx_error; 581 } 582 if (use_cache) 583 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst, 584 fl4.saddr); 585 } 586 if (rt->dst.dev == dev) { 587 ip_rt_put(rt); 588 dev->stats.collisions++; 589 goto tx_error; 590 } 591 592 if (key->tun_flags & TUNNEL_DONT_FRAGMENT) 593 df = htons(IP_DF); 594 if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, tunnel_hlen, 595 key->u.ipv4.dst, true)) { 596 ip_rt_put(rt); 597 goto tx_error; 598 } 599 600 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); 601 ttl = key->ttl; 602 if (ttl == 0) { 603 if (skb->protocol == htons(ETH_P_IP)) 604 ttl = inner_iph->ttl; 605 else if (skb->protocol == htons(ETH_P_IPV6)) 606 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; 607 else 608 ttl = ip4_dst_hoplimit(&rt->dst); 609 } 610 611 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; 612 if (headroom > dev->needed_headroom) 613 dev->needed_headroom = headroom; 614 615 if (skb_cow_head(skb, dev->needed_headroom)) { 616 ip_rt_put(rt); 617 goto tx_dropped; 618 } 619 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl, 620 df, !net_eq(tunnel->net, dev_net(dev))); 621 return; 622 tx_error: 623 dev->stats.tx_errors++; 624 goto kfree; 625 tx_dropped: 626 dev->stats.tx_dropped++; 627 kfree: 628 kfree_skb(skb); 629 } 630 EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit); 631 632 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 633 const struct iphdr *tnl_params, u8 protocol) 634 { 635 struct ip_tunnel *tunnel = netdev_priv(dev); 636 struct ip_tunnel_info *tun_info = NULL; 637 const struct iphdr *inner_iph; 638 unsigned int max_headroom; /* The extra header space needed */ 639 struct rtable *rt = NULL; /* Route to the other host */ 640 bool use_cache = false; 641 struct flowi4 fl4; 642 bool md = false; 643 bool connected; 644 u8 tos, ttl; 645 __be32 dst; 646 __be16 df; 647 648 inner_iph = (const struct iphdr *)skb_inner_network_header(skb); 649 connected = (tunnel->parms.iph.daddr != 0); 650 651 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 652 653 dst = tnl_params->daddr; 654 if (dst == 0) { 655 /* NBMA tunnel */ 656 657 if (!skb_dst(skb)) { 658 dev->stats.tx_fifo_errors++; 659 goto tx_error; 660 } 661 662 tun_info = skb_tunnel_info(skb); 663 if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX) && 664 ip_tunnel_info_af(tun_info) == AF_INET && 665 tun_info->key.u.ipv4.dst) { 666 dst = tun_info->key.u.ipv4.dst; 667 md = true; 668 connected = true; 669 } 670 else if (skb->protocol == htons(ETH_P_IP)) { 671 rt = skb_rtable(skb); 672 dst = rt_nexthop(rt, inner_iph->daddr); 673 } 674 #if IS_ENABLED(CONFIG_IPV6) 675 else if (skb->protocol == htons(ETH_P_IPV6)) { 676 const struct in6_addr *addr6; 677 struct neighbour *neigh; 678 bool do_tx_error_icmp; 679 int addr_type; 680 681 neigh = dst_neigh_lookup(skb_dst(skb), 682 &ipv6_hdr(skb)->daddr); 683 if (!neigh) 684 goto tx_error; 685 686 addr6 = (const struct in6_addr *)&neigh->primary_key; 687 addr_type = ipv6_addr_type(addr6); 688 689 if (addr_type == IPV6_ADDR_ANY) { 690 addr6 = &ipv6_hdr(skb)->daddr; 691 addr_type = ipv6_addr_type(addr6); 692 } 693 694 if ((addr_type & IPV6_ADDR_COMPATv4) == 0) 695 do_tx_error_icmp = true; 696 else { 697 do_tx_error_icmp = false; 698 dst = addr6->s6_addr32[3]; 699 } 700 neigh_release(neigh); 701 if (do_tx_error_icmp) 702 goto tx_error_icmp; 703 } 704 #endif 705 else 706 goto tx_error; 707 708 if (!md) 709 connected = false; 710 } 711 712 tos = tnl_params->tos; 713 if (tos & 0x1) { 714 tos &= ~0x1; 715 if (skb->protocol == htons(ETH_P_IP)) { 716 tos = inner_iph->tos; 717 connected = false; 718 } else if (skb->protocol == htons(ETH_P_IPV6)) { 719 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); 720 connected = false; 721 } 722 } 723 724 ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr, 725 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link, 726 tunnel->fwmark, skb_get_hash(skb)); 727 728 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) 729 goto tx_error; 730 731 if (connected && md) { 732 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info); 733 if (use_cache) 734 rt = dst_cache_get_ip4(&tun_info->dst_cache, 735 &fl4.saddr); 736 } else { 737 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, 738 &fl4.saddr) : NULL; 739 } 740 741 if (!rt) { 742 rt = ip_route_output_key(tunnel->net, &fl4); 743 744 if (IS_ERR(rt)) { 745 dev->stats.tx_carrier_errors++; 746 goto tx_error; 747 } 748 if (use_cache) 749 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst, 750 fl4.saddr); 751 else if (!md && connected) 752 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, 753 fl4.saddr); 754 } 755 756 if (rt->dst.dev == dev) { 757 ip_rt_put(rt); 758 dev->stats.collisions++; 759 goto tx_error; 760 } 761 762 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph, 763 0, 0, false)) { 764 ip_rt_put(rt); 765 goto tx_error; 766 } 767 768 if (tunnel->err_count > 0) { 769 if (time_before(jiffies, 770 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 771 tunnel->err_count--; 772 773 dst_link_failure(skb); 774 } else 775 tunnel->err_count = 0; 776 } 777 778 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); 779 ttl = tnl_params->ttl; 780 if (ttl == 0) { 781 if (skb->protocol == htons(ETH_P_IP)) 782 ttl = inner_iph->ttl; 783 #if IS_ENABLED(CONFIG_IPV6) 784 else if (skb->protocol == htons(ETH_P_IPV6)) 785 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; 786 #endif 787 else 788 ttl = ip4_dst_hoplimit(&rt->dst); 789 } 790 791 df = tnl_params->frag_off; 792 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df) 793 df |= (inner_iph->frag_off&htons(IP_DF)); 794 795 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) 796 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap); 797 if (max_headroom > dev->needed_headroom) 798 dev->needed_headroom = max_headroom; 799 800 if (skb_cow_head(skb, dev->needed_headroom)) { 801 ip_rt_put(rt); 802 dev->stats.tx_dropped++; 803 kfree_skb(skb); 804 return; 805 } 806 807 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, 808 df, !net_eq(tunnel->net, dev_net(dev))); 809 return; 810 811 #if IS_ENABLED(CONFIG_IPV6) 812 tx_error_icmp: 813 dst_link_failure(skb); 814 #endif 815 tx_error: 816 dev->stats.tx_errors++; 817 kfree_skb(skb); 818 } 819 EXPORT_SYMBOL_GPL(ip_tunnel_xmit); 820 821 static void ip_tunnel_update(struct ip_tunnel_net *itn, 822 struct ip_tunnel *t, 823 struct net_device *dev, 824 struct ip_tunnel_parm *p, 825 bool set_mtu, 826 __u32 fwmark) 827 { 828 ip_tunnel_del(itn, t); 829 t->parms.iph.saddr = p->iph.saddr; 830 t->parms.iph.daddr = p->iph.daddr; 831 t->parms.i_key = p->i_key; 832 t->parms.o_key = p->o_key; 833 if (dev->type != ARPHRD_ETHER) { 834 memcpy(dev->dev_addr, &p->iph.saddr, 4); 835 memcpy(dev->broadcast, &p->iph.daddr, 4); 836 } 837 ip_tunnel_add(itn, t); 838 839 t->parms.iph.ttl = p->iph.ttl; 840 t->parms.iph.tos = p->iph.tos; 841 t->parms.iph.frag_off = p->iph.frag_off; 842 843 if (t->parms.link != p->link || t->fwmark != fwmark) { 844 int mtu; 845 846 t->parms.link = p->link; 847 t->fwmark = fwmark; 848 mtu = ip_tunnel_bind_dev(dev); 849 if (set_mtu) 850 dev->mtu = mtu; 851 } 852 dst_cache_reset(&t->dst_cache); 853 netdev_state_change(dev); 854 } 855 856 int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) 857 { 858 int err = 0; 859 struct ip_tunnel *t = netdev_priv(dev); 860 struct net *net = t->net; 861 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id); 862 863 switch (cmd) { 864 case SIOCGETTUNNEL: 865 if (dev == itn->fb_tunnel_dev) { 866 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 867 if (!t) 868 t = netdev_priv(dev); 869 } 870 memcpy(p, &t->parms, sizeof(*p)); 871 break; 872 873 case SIOCADDTUNNEL: 874 case SIOCCHGTUNNEL: 875 err = -EPERM; 876 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 877 goto done; 878 if (p->iph.ttl) 879 p->iph.frag_off |= htons(IP_DF); 880 if (!(p->i_flags & VTI_ISVTI)) { 881 if (!(p->i_flags & TUNNEL_KEY)) 882 p->i_key = 0; 883 if (!(p->o_flags & TUNNEL_KEY)) 884 p->o_key = 0; 885 } 886 887 t = ip_tunnel_find(itn, p, itn->type); 888 889 if (cmd == SIOCADDTUNNEL) { 890 if (!t) { 891 t = ip_tunnel_create(net, itn, p); 892 err = PTR_ERR_OR_ZERO(t); 893 break; 894 } 895 896 err = -EEXIST; 897 break; 898 } 899 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 900 if (t) { 901 if (t->dev != dev) { 902 err = -EEXIST; 903 break; 904 } 905 } else { 906 unsigned int nflags = 0; 907 908 if (ipv4_is_multicast(p->iph.daddr)) 909 nflags = IFF_BROADCAST; 910 else if (p->iph.daddr) 911 nflags = IFF_POINTOPOINT; 912 913 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) { 914 err = -EINVAL; 915 break; 916 } 917 918 t = netdev_priv(dev); 919 } 920 } 921 922 if (t) { 923 err = 0; 924 ip_tunnel_update(itn, t, dev, p, true, 0); 925 } else { 926 err = -ENOENT; 927 } 928 break; 929 930 case SIOCDELTUNNEL: 931 err = -EPERM; 932 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 933 goto done; 934 935 if (dev == itn->fb_tunnel_dev) { 936 err = -ENOENT; 937 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); 938 if (!t) 939 goto done; 940 err = -EPERM; 941 if (t == netdev_priv(itn->fb_tunnel_dev)) 942 goto done; 943 dev = t->dev; 944 } 945 unregister_netdevice(dev); 946 err = 0; 947 break; 948 949 default: 950 err = -EINVAL; 951 } 952 953 done: 954 return err; 955 } 956 EXPORT_SYMBOL_GPL(ip_tunnel_ctl); 957 958 int ip_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 959 { 960 struct ip_tunnel_parm p; 961 int err; 962 963 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 964 return -EFAULT; 965 err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, cmd); 966 if (!err && copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 967 return -EFAULT; 968 return err; 969 } 970 EXPORT_SYMBOL_GPL(ip_tunnel_ioctl); 971 972 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict) 973 { 974 struct ip_tunnel *tunnel = netdev_priv(dev); 975 int t_hlen = tunnel->hlen + sizeof(struct iphdr); 976 int max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen; 977 978 if (new_mtu < ETH_MIN_MTU) 979 return -EINVAL; 980 981 if (new_mtu > max_mtu) { 982 if (strict) 983 return -EINVAL; 984 985 new_mtu = max_mtu; 986 } 987 988 dev->mtu = new_mtu; 989 return 0; 990 } 991 EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu); 992 993 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu) 994 { 995 return __ip_tunnel_change_mtu(dev, new_mtu, true); 996 } 997 EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu); 998 999 static void ip_tunnel_dev_free(struct net_device *dev) 1000 { 1001 struct ip_tunnel *tunnel = netdev_priv(dev); 1002 1003 gro_cells_destroy(&tunnel->gro_cells); 1004 dst_cache_destroy(&tunnel->dst_cache); 1005 free_percpu(dev->tstats); 1006 } 1007 1008 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head) 1009 { 1010 struct ip_tunnel *tunnel = netdev_priv(dev); 1011 struct ip_tunnel_net *itn; 1012 1013 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id); 1014 1015 if (itn->fb_tunnel_dev != dev) { 1016 ip_tunnel_del(itn, netdev_priv(dev)); 1017 unregister_netdevice_queue(dev, head); 1018 } 1019 } 1020 EXPORT_SYMBOL_GPL(ip_tunnel_dellink); 1021 1022 struct net *ip_tunnel_get_link_net(const struct net_device *dev) 1023 { 1024 struct ip_tunnel *tunnel = netdev_priv(dev); 1025 1026 return tunnel->net; 1027 } 1028 EXPORT_SYMBOL(ip_tunnel_get_link_net); 1029 1030 int ip_tunnel_get_iflink(const struct net_device *dev) 1031 { 1032 struct ip_tunnel *tunnel = netdev_priv(dev); 1033 1034 return tunnel->parms.link; 1035 } 1036 EXPORT_SYMBOL(ip_tunnel_get_iflink); 1037 1038 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, 1039 struct rtnl_link_ops *ops, char *devname) 1040 { 1041 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id); 1042 struct ip_tunnel_parm parms; 1043 unsigned int i; 1044 1045 itn->rtnl_link_ops = ops; 1046 for (i = 0; i < IP_TNL_HASH_SIZE; i++) 1047 INIT_HLIST_HEAD(&itn->tunnels[i]); 1048 1049 if (!ops || !net_has_fallback_tunnels(net)) { 1050 struct ip_tunnel_net *it_init_net; 1051 1052 it_init_net = net_generic(&init_net, ip_tnl_net_id); 1053 itn->type = it_init_net->type; 1054 itn->fb_tunnel_dev = NULL; 1055 return 0; 1056 } 1057 1058 memset(&parms, 0, sizeof(parms)); 1059 if (devname) 1060 strlcpy(parms.name, devname, IFNAMSIZ); 1061 1062 rtnl_lock(); 1063 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms); 1064 /* FB netdevice is special: we have one, and only one per netns. 1065 * Allowing to move it to another netns is clearly unsafe. 1066 */ 1067 if (!IS_ERR(itn->fb_tunnel_dev)) { 1068 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1069 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev); 1070 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev)); 1071 itn->type = itn->fb_tunnel_dev->type; 1072 } 1073 rtnl_unlock(); 1074 1075 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev); 1076 } 1077 EXPORT_SYMBOL_GPL(ip_tunnel_init_net); 1078 1079 static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn, 1080 struct list_head *head, 1081 struct rtnl_link_ops *ops) 1082 { 1083 struct net_device *dev, *aux; 1084 int h; 1085 1086 for_each_netdev_safe(net, dev, aux) 1087 if (dev->rtnl_link_ops == ops) 1088 unregister_netdevice_queue(dev, head); 1089 1090 for (h = 0; h < IP_TNL_HASH_SIZE; h++) { 1091 struct ip_tunnel *t; 1092 struct hlist_node *n; 1093 struct hlist_head *thead = &itn->tunnels[h]; 1094 1095 hlist_for_each_entry_safe(t, n, thead, hash_node) 1096 /* If dev is in the same netns, it has already 1097 * been added to the list by the previous loop. 1098 */ 1099 if (!net_eq(dev_net(t->dev), net)) 1100 unregister_netdevice_queue(t->dev, head); 1101 } 1102 } 1103 1104 void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id, 1105 struct rtnl_link_ops *ops) 1106 { 1107 struct ip_tunnel_net *itn; 1108 struct net *net; 1109 LIST_HEAD(list); 1110 1111 rtnl_lock(); 1112 list_for_each_entry(net, net_list, exit_list) { 1113 itn = net_generic(net, id); 1114 ip_tunnel_destroy(net, itn, &list, ops); 1115 } 1116 unregister_netdevice_many(&list); 1117 rtnl_unlock(); 1118 } 1119 EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets); 1120 1121 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 1122 struct ip_tunnel_parm *p, __u32 fwmark) 1123 { 1124 struct ip_tunnel *nt; 1125 struct net *net = dev_net(dev); 1126 struct ip_tunnel_net *itn; 1127 int mtu; 1128 int err; 1129 1130 nt = netdev_priv(dev); 1131 itn = net_generic(net, nt->ip_tnl_net_id); 1132 1133 if (nt->collect_md) { 1134 if (rtnl_dereference(itn->collect_md_tun)) 1135 return -EEXIST; 1136 } else { 1137 if (ip_tunnel_find(itn, p, dev->type)) 1138 return -EEXIST; 1139 } 1140 1141 nt->net = net; 1142 nt->parms = *p; 1143 nt->fwmark = fwmark; 1144 err = register_netdevice(dev); 1145 if (err) 1146 goto err_register_netdevice; 1147 1148 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1149 eth_hw_addr_random(dev); 1150 1151 mtu = ip_tunnel_bind_dev(dev); 1152 if (tb[IFLA_MTU]) { 1153 unsigned int max = IP_MAX_MTU - dev->hard_header_len - nt->hlen; 1154 1155 mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU, 1156 (unsigned int)(max - sizeof(struct iphdr))); 1157 } 1158 1159 err = dev_set_mtu(dev, mtu); 1160 if (err) 1161 goto err_dev_set_mtu; 1162 1163 ip_tunnel_add(itn, nt); 1164 return 0; 1165 1166 err_dev_set_mtu: 1167 unregister_netdevice(dev); 1168 err_register_netdevice: 1169 return err; 1170 } 1171 EXPORT_SYMBOL_GPL(ip_tunnel_newlink); 1172 1173 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], 1174 struct ip_tunnel_parm *p, __u32 fwmark) 1175 { 1176 struct ip_tunnel *t; 1177 struct ip_tunnel *tunnel = netdev_priv(dev); 1178 struct net *net = tunnel->net; 1179 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id); 1180 1181 if (dev == itn->fb_tunnel_dev) 1182 return -EINVAL; 1183 1184 t = ip_tunnel_find(itn, p, dev->type); 1185 1186 if (t) { 1187 if (t->dev != dev) 1188 return -EEXIST; 1189 } else { 1190 t = tunnel; 1191 1192 if (dev->type != ARPHRD_ETHER) { 1193 unsigned int nflags = 0; 1194 1195 if (ipv4_is_multicast(p->iph.daddr)) 1196 nflags = IFF_BROADCAST; 1197 else if (p->iph.daddr) 1198 nflags = IFF_POINTOPOINT; 1199 1200 if ((dev->flags ^ nflags) & 1201 (IFF_POINTOPOINT | IFF_BROADCAST)) 1202 return -EINVAL; 1203 } 1204 } 1205 1206 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark); 1207 return 0; 1208 } 1209 EXPORT_SYMBOL_GPL(ip_tunnel_changelink); 1210 1211 int ip_tunnel_init(struct net_device *dev) 1212 { 1213 struct ip_tunnel *tunnel = netdev_priv(dev); 1214 struct iphdr *iph = &tunnel->parms.iph; 1215 int err; 1216 1217 dev->needs_free_netdev = true; 1218 dev->priv_destructor = ip_tunnel_dev_free; 1219 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1220 if (!dev->tstats) 1221 return -ENOMEM; 1222 1223 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1224 if (err) { 1225 free_percpu(dev->tstats); 1226 return err; 1227 } 1228 1229 err = gro_cells_init(&tunnel->gro_cells, dev); 1230 if (err) { 1231 dst_cache_destroy(&tunnel->dst_cache); 1232 free_percpu(dev->tstats); 1233 return err; 1234 } 1235 1236 tunnel->dev = dev; 1237 tunnel->net = dev_net(dev); 1238 strcpy(tunnel->parms.name, dev->name); 1239 iph->version = 4; 1240 iph->ihl = 5; 1241 1242 if (tunnel->collect_md) 1243 netif_keep_dst(dev); 1244 return 0; 1245 } 1246 EXPORT_SYMBOL_GPL(ip_tunnel_init); 1247 1248 void ip_tunnel_uninit(struct net_device *dev) 1249 { 1250 struct ip_tunnel *tunnel = netdev_priv(dev); 1251 struct net *net = tunnel->net; 1252 struct ip_tunnel_net *itn; 1253 1254 itn = net_generic(net, tunnel->ip_tnl_net_id); 1255 ip_tunnel_del(itn, netdev_priv(dev)); 1256 if (itn->fb_tunnel_dev == dev) 1257 WRITE_ONCE(itn->fb_tunnel_dev, NULL); 1258 1259 dst_cache_reset(&tunnel->dst_cache); 1260 } 1261 EXPORT_SYMBOL_GPL(ip_tunnel_uninit); 1262 1263 /* Do least required initialization, rest of init is done in tunnel_init call */ 1264 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id) 1265 { 1266 struct ip_tunnel *tunnel = netdev_priv(dev); 1267 tunnel->ip_tnl_net_id = net_id; 1268 } 1269 EXPORT_SYMBOL_GPL(ip_tunnel_setup); 1270 1271 MODULE_LICENSE("GPL"); 1272