1 /* 2 * GRE over IPv6 protocol decoder. 3 * 4 * Authors: Dmitry Kozlov (xeb@mail.ru) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 * 11 */ 12 13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 14 15 #include <linux/capability.h> 16 #include <linux/module.h> 17 #include <linux/types.h> 18 #include <linux/kernel.h> 19 #include <linux/slab.h> 20 #include <linux/uaccess.h> 21 #include <linux/skbuff.h> 22 #include <linux/netdevice.h> 23 #include <linux/in.h> 24 #include <linux/tcp.h> 25 #include <linux/udp.h> 26 #include <linux/if_arp.h> 27 #include <linux/init.h> 28 #include <linux/in6.h> 29 #include <linux/inetdevice.h> 30 #include <linux/igmp.h> 31 #include <linux/netfilter_ipv4.h> 32 #include <linux/etherdevice.h> 33 #include <linux/if_ether.h> 34 #include <linux/hash.h> 35 #include <linux/if_tunnel.h> 36 #include <linux/ip6_tunnel.h> 37 38 #include <net/sock.h> 39 #include <net/ip.h> 40 #include <net/ip_tunnels.h> 41 #include <net/icmp.h> 42 #include <net/protocol.h> 43 #include <net/addrconf.h> 44 #include <net/arp.h> 45 #include <net/checksum.h> 46 #include <net/dsfield.h> 47 #include <net/inet_ecn.h> 48 #include <net/xfrm.h> 49 #include <net/net_namespace.h> 50 #include <net/netns/generic.h> 51 #include <net/rtnetlink.h> 52 53 #include <net/ipv6.h> 54 #include <net/ip6_fib.h> 55 #include <net/ip6_route.h> 56 #include <net/ip6_tunnel.h> 57 58 59 static bool log_ecn_error = true; 60 module_param(log_ecn_error, bool, 0644); 61 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 62 63 #define HASH_SIZE_SHIFT 5 64 #define HASH_SIZE (1 << HASH_SIZE_SHIFT) 65 66 static int ip6gre_net_id __read_mostly; 67 struct ip6gre_net { 68 struct ip6_tnl __rcu *tunnels[4][HASH_SIZE]; 69 70 struct net_device *fb_tunnel_dev; 71 }; 72 73 static struct rtnl_link_ops ip6gre_link_ops __read_mostly; 74 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly; 75 static int ip6gre_tunnel_init(struct net_device *dev); 76 static void ip6gre_tunnel_setup(struct net_device *dev); 77 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t); 78 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu); 79 80 /* Tunnel hash table */ 81 82 /* 83 4 hash tables: 84 85 3: (remote,local) 86 2: (remote,*) 87 1: (*,local) 88 0: (*,*) 89 90 We require exact key match i.e. if a key is present in packet 91 it will match only tunnel with the same key; if it is not present, 92 it will match only keyless tunnel. 93 94 All keysless packets, if not matched configured keyless tunnels 95 will match fallback tunnel. 96 */ 97 98 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 1)) 99 static u32 HASH_ADDR(const struct in6_addr *addr) 100 { 101 u32 hash = ipv6_addr_hash(addr); 102 103 return hash_32(hash, HASH_SIZE_SHIFT); 104 } 105 106 #define tunnels_r_l tunnels[3] 107 #define tunnels_r tunnels[2] 108 #define tunnels_l tunnels[1] 109 #define tunnels_wc tunnels[0] 110 111 /* Given src, dst and key, find appropriate for input tunnel. */ 112 113 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev, 114 const struct in6_addr *remote, const struct in6_addr *local, 115 __be32 key, __be16 gre_proto) 116 { 117 struct net *net = dev_net(dev); 118 int link = dev->ifindex; 119 unsigned int h0 = HASH_ADDR(remote); 120 unsigned int h1 = HASH_KEY(key); 121 struct ip6_tnl *t, *cand = NULL; 122 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 123 int dev_type = (gre_proto == htons(ETH_P_TEB)) ? 124 ARPHRD_ETHER : ARPHRD_IP6GRE; 125 int score, cand_score = 4; 126 127 for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) { 128 if (!ipv6_addr_equal(local, &t->parms.laddr) || 129 !ipv6_addr_equal(remote, &t->parms.raddr) || 130 key != t->parms.i_key || 131 !(t->dev->flags & IFF_UP)) 132 continue; 133 134 if (t->dev->type != ARPHRD_IP6GRE && 135 t->dev->type != dev_type) 136 continue; 137 138 score = 0; 139 if (t->parms.link != link) 140 score |= 1; 141 if (t->dev->type != dev_type) 142 score |= 2; 143 if (score == 0) 144 return t; 145 146 if (score < cand_score) { 147 cand = t; 148 cand_score = score; 149 } 150 } 151 152 for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) { 153 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 154 key != t->parms.i_key || 155 !(t->dev->flags & IFF_UP)) 156 continue; 157 158 if (t->dev->type != ARPHRD_IP6GRE && 159 t->dev->type != dev_type) 160 continue; 161 162 score = 0; 163 if (t->parms.link != link) 164 score |= 1; 165 if (t->dev->type != dev_type) 166 score |= 2; 167 if (score == 0) 168 return t; 169 170 if (score < cand_score) { 171 cand = t; 172 cand_score = score; 173 } 174 } 175 176 for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) { 177 if ((!ipv6_addr_equal(local, &t->parms.laddr) && 178 (!ipv6_addr_equal(local, &t->parms.raddr) || 179 !ipv6_addr_is_multicast(local))) || 180 key != t->parms.i_key || 181 !(t->dev->flags & IFF_UP)) 182 continue; 183 184 if (t->dev->type != ARPHRD_IP6GRE && 185 t->dev->type != dev_type) 186 continue; 187 188 score = 0; 189 if (t->parms.link != link) 190 score |= 1; 191 if (t->dev->type != dev_type) 192 score |= 2; 193 if (score == 0) 194 return t; 195 196 if (score < cand_score) { 197 cand = t; 198 cand_score = score; 199 } 200 } 201 202 for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) { 203 if (t->parms.i_key != key || 204 !(t->dev->flags & IFF_UP)) 205 continue; 206 207 if (t->dev->type != ARPHRD_IP6GRE && 208 t->dev->type != dev_type) 209 continue; 210 211 score = 0; 212 if (t->parms.link != link) 213 score |= 1; 214 if (t->dev->type != dev_type) 215 score |= 2; 216 if (score == 0) 217 return t; 218 219 if (score < cand_score) { 220 cand = t; 221 cand_score = score; 222 } 223 } 224 225 if (cand) 226 return cand; 227 228 dev = ign->fb_tunnel_dev; 229 if (dev->flags & IFF_UP) 230 return netdev_priv(dev); 231 232 return NULL; 233 } 234 235 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign, 236 const struct __ip6_tnl_parm *p) 237 { 238 const struct in6_addr *remote = &p->raddr; 239 const struct in6_addr *local = &p->laddr; 240 unsigned int h = HASH_KEY(p->i_key); 241 int prio = 0; 242 243 if (!ipv6_addr_any(local)) 244 prio |= 1; 245 if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) { 246 prio |= 2; 247 h ^= HASH_ADDR(remote); 248 } 249 250 return &ign->tunnels[prio][h]; 251 } 252 253 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign, 254 const struct ip6_tnl *t) 255 { 256 return __ip6gre_bucket(ign, &t->parms); 257 } 258 259 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t) 260 { 261 struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t); 262 263 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 264 rcu_assign_pointer(*tp, t); 265 } 266 267 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t) 268 { 269 struct ip6_tnl __rcu **tp; 270 struct ip6_tnl *iter; 271 272 for (tp = ip6gre_bucket(ign, t); 273 (iter = rtnl_dereference(*tp)) != NULL; 274 tp = &iter->next) { 275 if (t == iter) { 276 rcu_assign_pointer(*tp, t->next); 277 break; 278 } 279 } 280 } 281 282 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net, 283 const struct __ip6_tnl_parm *parms, 284 int type) 285 { 286 const struct in6_addr *remote = &parms->raddr; 287 const struct in6_addr *local = &parms->laddr; 288 __be32 key = parms->i_key; 289 int link = parms->link; 290 struct ip6_tnl *t; 291 struct ip6_tnl __rcu **tp; 292 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 293 294 for (tp = __ip6gre_bucket(ign, parms); 295 (t = rtnl_dereference(*tp)) != NULL; 296 tp = &t->next) 297 if (ipv6_addr_equal(local, &t->parms.laddr) && 298 ipv6_addr_equal(remote, &t->parms.raddr) && 299 key == t->parms.i_key && 300 link == t->parms.link && 301 type == t->dev->type) 302 break; 303 304 return t; 305 } 306 307 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, 308 const struct __ip6_tnl_parm *parms, int create) 309 { 310 struct ip6_tnl *t, *nt; 311 struct net_device *dev; 312 char name[IFNAMSIZ]; 313 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 314 315 t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE); 316 if (t && create) 317 return NULL; 318 if (t || !create) 319 return t; 320 321 if (parms->name[0]) 322 strlcpy(name, parms->name, IFNAMSIZ); 323 else 324 strcpy(name, "ip6gre%d"); 325 326 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 327 ip6gre_tunnel_setup); 328 if (!dev) 329 return NULL; 330 331 dev_net_set(dev, net); 332 333 nt = netdev_priv(dev); 334 nt->parms = *parms; 335 dev->rtnl_link_ops = &ip6gre_link_ops; 336 337 nt->dev = dev; 338 nt->net = dev_net(dev); 339 ip6gre_tnl_link_config(nt, 1); 340 341 if (register_netdevice(dev) < 0) 342 goto failed_free; 343 344 /* Can use a lockless transmit, unless we generate output sequences */ 345 if (!(nt->parms.o_flags & GRE_SEQ)) 346 dev->features |= NETIF_F_LLTX; 347 348 dev_hold(dev); 349 ip6gre_tunnel_link(ign, nt); 350 return nt; 351 352 failed_free: 353 free_netdev(dev); 354 return NULL; 355 } 356 357 static void ip6gre_tunnel_uninit(struct net_device *dev) 358 { 359 struct ip6_tnl *t = netdev_priv(dev); 360 struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id); 361 362 ip6gre_tunnel_unlink(ign, t); 363 dst_cache_reset(&t->dst_cache); 364 dev_put(dev); 365 } 366 367 368 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 369 u8 type, u8 code, int offset, __be32 info) 370 { 371 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 372 __be16 *p = (__be16 *)(skb->data + offset); 373 int grehlen = offset + 4; 374 struct ip6_tnl *t; 375 __be16 flags; 376 377 flags = p[0]; 378 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 379 if (flags&(GRE_VERSION|GRE_ROUTING)) 380 return; 381 if (flags&GRE_KEY) { 382 grehlen += 4; 383 if (flags&GRE_CSUM) 384 grehlen += 4; 385 } 386 } 387 388 /* If only 8 bytes returned, keyed message will be dropped here */ 389 if (!pskb_may_pull(skb, grehlen)) 390 return; 391 ipv6h = (const struct ipv6hdr *)skb->data; 392 p = (__be16 *)(skb->data + offset); 393 394 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 395 flags & GRE_KEY ? 396 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 397 p[1]); 398 if (!t) 399 return; 400 401 switch (type) { 402 __u32 teli; 403 struct ipv6_tlv_tnl_enc_lim *tel; 404 __u32 mtu; 405 case ICMPV6_DEST_UNREACH: 406 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 407 t->parms.name); 408 break; 409 case ICMPV6_TIME_EXCEED: 410 if (code == ICMPV6_EXC_HOPLIMIT) { 411 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 412 t->parms.name); 413 } 414 break; 415 case ICMPV6_PARAMPROB: 416 teli = 0; 417 if (code == ICMPV6_HDR_FIELD) 418 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 419 420 if (teli && teli == be32_to_cpu(info) - 2) { 421 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 422 if (tel->encap_limit == 0) { 423 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 424 t->parms.name); 425 } 426 } else { 427 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 428 t->parms.name); 429 } 430 break; 431 case ICMPV6_PKT_TOOBIG: 432 mtu = be32_to_cpu(info) - offset; 433 if (mtu < IPV6_MIN_MTU) 434 mtu = IPV6_MIN_MTU; 435 t->dev->mtu = mtu; 436 break; 437 } 438 439 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 440 t->err_count++; 441 else 442 t->err_count = 1; 443 t->err_time = jiffies; 444 } 445 446 static int ip6gre_rcv(struct sk_buff *skb) 447 { 448 const struct ipv6hdr *ipv6h; 449 u8 *h; 450 __be16 flags; 451 __sum16 csum = 0; 452 __be32 key = 0; 453 u32 seqno = 0; 454 struct ip6_tnl *tunnel; 455 int offset = 4; 456 __be16 gre_proto; 457 int err; 458 459 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 460 goto drop; 461 462 ipv6h = ipv6_hdr(skb); 463 h = skb->data; 464 flags = *(__be16 *)h; 465 466 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 467 /* - Version must be 0. 468 - We do not support routing headers. 469 */ 470 if (flags&(GRE_VERSION|GRE_ROUTING)) 471 goto drop; 472 473 if (flags&GRE_CSUM) { 474 csum = skb_checksum_simple_validate(skb); 475 offset += 4; 476 } 477 if (flags&GRE_KEY) { 478 key = *(__be32 *)(h + offset); 479 offset += 4; 480 } 481 if (flags&GRE_SEQ) { 482 seqno = ntohl(*(__be32 *)(h + offset)); 483 offset += 4; 484 } 485 } 486 487 gre_proto = *(__be16 *)(h + 2); 488 489 tunnel = ip6gre_tunnel_lookup(skb->dev, 490 &ipv6h->saddr, &ipv6h->daddr, key, 491 gre_proto); 492 if (tunnel) { 493 struct pcpu_sw_netstats *tstats; 494 495 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 496 goto drop; 497 498 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 499 tunnel->dev->stats.rx_dropped++; 500 goto drop; 501 } 502 503 skb->protocol = gre_proto; 504 /* WCCP version 1 and 2 protocol decoding. 505 * - Change protocol to IPv6 506 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 507 */ 508 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 509 skb->protocol = htons(ETH_P_IPV6); 510 if ((*(h + offset) & 0xF0) != 0x40) 511 offset += 4; 512 } 513 514 skb->mac_header = skb->network_header; 515 __pskb_pull(skb, offset); 516 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 517 518 if (((flags&GRE_CSUM) && csum) || 519 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 520 tunnel->dev->stats.rx_crc_errors++; 521 tunnel->dev->stats.rx_errors++; 522 goto drop; 523 } 524 if (tunnel->parms.i_flags&GRE_SEQ) { 525 if (!(flags&GRE_SEQ) || 526 (tunnel->i_seqno && 527 (s32)(seqno - tunnel->i_seqno) < 0)) { 528 tunnel->dev->stats.rx_fifo_errors++; 529 tunnel->dev->stats.rx_errors++; 530 goto drop; 531 } 532 tunnel->i_seqno = seqno + 1; 533 } 534 535 /* Warning: All skb pointers will be invalidated! */ 536 if (tunnel->dev->type == ARPHRD_ETHER) { 537 if (!pskb_may_pull(skb, ETH_HLEN)) { 538 tunnel->dev->stats.rx_length_errors++; 539 tunnel->dev->stats.rx_errors++; 540 goto drop; 541 } 542 543 ipv6h = ipv6_hdr(skb); 544 skb->protocol = eth_type_trans(skb, tunnel->dev); 545 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 546 } 547 548 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 549 550 skb_reset_network_header(skb); 551 552 err = IP6_ECN_decapsulate(ipv6h, skb); 553 if (unlikely(err)) { 554 if (log_ecn_error) 555 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 556 &ipv6h->saddr, 557 ipv6_get_dsfield(ipv6h)); 558 if (err > 1) { 559 ++tunnel->dev->stats.rx_frame_errors; 560 ++tunnel->dev->stats.rx_errors; 561 goto drop; 562 } 563 } 564 565 tstats = this_cpu_ptr(tunnel->dev->tstats); 566 u64_stats_update_begin(&tstats->syncp); 567 tstats->rx_packets++; 568 tstats->rx_bytes += skb->len; 569 u64_stats_update_end(&tstats->syncp); 570 571 netif_rx(skb); 572 573 return 0; 574 } 575 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 576 577 drop: 578 kfree_skb(skb); 579 return 0; 580 } 581 582 struct ipv6_tel_txoption { 583 struct ipv6_txoptions ops; 584 __u8 dst_opt[8]; 585 }; 586 587 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 588 { 589 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 590 591 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 592 opt->dst_opt[3] = 1; 593 opt->dst_opt[4] = encap_limit; 594 opt->dst_opt[5] = IPV6_TLV_PADN; 595 opt->dst_opt[6] = 1; 596 597 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 598 opt->ops.opt_nflen = 8; 599 } 600 601 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 602 struct net_device *dev, 603 __u8 dsfield, 604 struct flowi6 *fl6, 605 int encap_limit, 606 __u32 *pmtu) 607 { 608 struct ip6_tnl *tunnel = netdev_priv(dev); 609 struct net *net = tunnel->net; 610 struct net_device *tdev; /* Device to other host */ 611 struct ipv6hdr *ipv6h; /* Our new IP header */ 612 unsigned int max_headroom = 0; /* The extra header space needed */ 613 int gre_hlen; 614 struct ipv6_tel_txoption opt; 615 int mtu; 616 struct dst_entry *dst = NULL, *ndst = NULL; 617 struct net_device_stats *stats = &tunnel->dev->stats; 618 int err = -1; 619 u8 proto; 620 struct sk_buff *new_skb; 621 __be16 protocol; 622 623 if (dev->type == ARPHRD_ETHER) 624 IPCB(skb)->flags = 0; 625 626 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 627 gre_hlen = 0; 628 ipv6h = (struct ipv6hdr *)skb->data; 629 fl6->daddr = ipv6h->daddr; 630 } else { 631 gre_hlen = tunnel->hlen; 632 fl6->daddr = tunnel->parms.raddr; 633 } 634 635 if (!fl6->flowi6_mark) 636 dst = dst_cache_get(&tunnel->dst_cache); 637 638 if (!dst) { 639 dst = ip6_route_output(net, NULL, fl6); 640 641 if (dst->error) 642 goto tx_err_link_failure; 643 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 644 if (IS_ERR(dst)) { 645 err = PTR_ERR(dst); 646 dst = NULL; 647 goto tx_err_link_failure; 648 } 649 ndst = dst; 650 } 651 652 tdev = dst->dev; 653 654 if (tdev == dev) { 655 stats->collisions++; 656 net_warn_ratelimited("%s: Local routing loop detected!\n", 657 tunnel->parms.name); 658 goto tx_err_dst_release; 659 } 660 661 mtu = dst_mtu(dst) - sizeof(*ipv6h); 662 if (encap_limit >= 0) { 663 max_headroom += 8; 664 mtu -= 8; 665 } 666 if (mtu < IPV6_MIN_MTU) 667 mtu = IPV6_MIN_MTU; 668 if (skb_dst(skb)) 669 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 670 if (skb->len > mtu) { 671 *pmtu = mtu; 672 err = -EMSGSIZE; 673 goto tx_err_dst_release; 674 } 675 676 if (tunnel->err_count > 0) { 677 if (time_before(jiffies, 678 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 679 tunnel->err_count--; 680 681 dst_link_failure(skb); 682 } else 683 tunnel->err_count = 0; 684 } 685 686 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); 687 688 max_headroom += LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; 689 690 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 691 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 692 new_skb = skb_realloc_headroom(skb, max_headroom); 693 if (max_headroom > dev->needed_headroom) 694 dev->needed_headroom = max_headroom; 695 if (!new_skb) 696 goto tx_err_dst_release; 697 698 if (skb->sk) 699 skb_set_owner_w(new_skb, skb->sk); 700 consume_skb(skb); 701 skb = new_skb; 702 } 703 704 if (!fl6->flowi6_mark && ndst) 705 dst_cache_set_ip6(&tunnel->dst_cache, ndst, &fl6->saddr); 706 skb_dst_set(skb, dst); 707 708 proto = NEXTHDR_GRE; 709 if (encap_limit >= 0) { 710 init_tel_txopt(&opt, encap_limit); 711 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 712 } 713 714 if (likely(!skb->encapsulation)) { 715 skb_reset_inner_headers(skb); 716 skb->encapsulation = 1; 717 } 718 719 skb_push(skb, gre_hlen); 720 skb_reset_network_header(skb); 721 skb_set_transport_header(skb, sizeof(*ipv6h)); 722 723 /* 724 * Push down and install the IP header. 725 */ 726 ipv6h = ipv6_hdr(skb); 727 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), 728 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 729 ipv6h->hop_limit = tunnel->parms.hop_limit; 730 ipv6h->nexthdr = proto; 731 ipv6h->saddr = fl6->saddr; 732 ipv6h->daddr = fl6->daddr; 733 734 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 735 protocol = (dev->type == ARPHRD_ETHER) ? 736 htons(ETH_P_TEB) : skb->protocol; 737 ((__be16 *)(ipv6h + 1))[1] = protocol; 738 739 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 740 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 741 742 if (tunnel->parms.o_flags&GRE_SEQ) { 743 ++tunnel->o_seqno; 744 *ptr = htonl(tunnel->o_seqno); 745 ptr--; 746 } 747 if (tunnel->parms.o_flags&GRE_KEY) { 748 *ptr = tunnel->parms.o_key; 749 ptr--; 750 } 751 if (tunnel->parms.o_flags&GRE_CSUM) { 752 *ptr = 0; 753 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 754 skb->len - sizeof(struct ipv6hdr)); 755 } 756 } 757 758 skb_set_inner_protocol(skb, protocol); 759 760 ip6tunnel_xmit(NULL, skb, dev); 761 return 0; 762 tx_err_link_failure: 763 stats->tx_carrier_errors++; 764 dst_link_failure(skb); 765 tx_err_dst_release: 766 dst_release(dst); 767 return err; 768 } 769 770 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 771 { 772 struct ip6_tnl *t = netdev_priv(dev); 773 const struct iphdr *iph = ip_hdr(skb); 774 int encap_limit = -1; 775 struct flowi6 fl6; 776 __u8 dsfield; 777 __u32 mtu; 778 int err; 779 780 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 781 782 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 783 encap_limit = t->parms.encap_limit; 784 785 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 786 fl6.flowi6_proto = IPPROTO_GRE; 787 788 dsfield = ipv4_get_dsfield(iph); 789 790 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 791 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 792 & IPV6_TCLASS_MASK; 793 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 794 fl6.flowi6_mark = skb->mark; 795 796 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 797 if (err != 0) { 798 /* XXX: send ICMP error even if DF is not set. */ 799 if (err == -EMSGSIZE) 800 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 801 htonl(mtu)); 802 return -1; 803 } 804 805 return 0; 806 } 807 808 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 809 { 810 struct ip6_tnl *t = netdev_priv(dev); 811 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 812 int encap_limit = -1; 813 __u16 offset; 814 struct flowi6 fl6; 815 __u8 dsfield; 816 __u32 mtu; 817 int err; 818 819 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 820 return -1; 821 822 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 823 if (offset > 0) { 824 struct ipv6_tlv_tnl_enc_lim *tel; 825 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 826 if (tel->encap_limit == 0) { 827 icmpv6_send(skb, ICMPV6_PARAMPROB, 828 ICMPV6_HDR_FIELD, offset + 2); 829 return -1; 830 } 831 encap_limit = tel->encap_limit - 1; 832 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 833 encap_limit = t->parms.encap_limit; 834 835 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 836 fl6.flowi6_proto = IPPROTO_GRE; 837 838 dsfield = ipv6_get_dsfield(ipv6h); 839 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 840 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 841 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 842 fl6.flowlabel |= ip6_flowlabel(ipv6h); 843 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 844 fl6.flowi6_mark = skb->mark; 845 846 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 847 if (err != 0) { 848 if (err == -EMSGSIZE) 849 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 850 return -1; 851 } 852 853 return 0; 854 } 855 856 /** 857 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 858 * @t: the outgoing tunnel device 859 * @hdr: IPv6 header from the incoming packet 860 * 861 * Description: 862 * Avoid trivial tunneling loop by checking that tunnel exit-point 863 * doesn't match source of incoming packet. 864 * 865 * Return: 866 * 1 if conflict, 867 * 0 else 868 **/ 869 870 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 871 const struct ipv6hdr *hdr) 872 { 873 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 874 } 875 876 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 877 { 878 struct ip6_tnl *t = netdev_priv(dev); 879 int encap_limit = -1; 880 struct flowi6 fl6; 881 __u32 mtu; 882 int err; 883 884 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 885 encap_limit = t->parms.encap_limit; 886 887 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 888 fl6.flowi6_proto = skb->protocol; 889 890 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 891 892 return err; 893 } 894 895 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 896 struct net_device *dev) 897 { 898 struct ip6_tnl *t = netdev_priv(dev); 899 struct net_device_stats *stats = &t->dev->stats; 900 int ret; 901 902 if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr)) 903 goto tx_err; 904 905 switch (skb->protocol) { 906 case htons(ETH_P_IP): 907 ret = ip6gre_xmit_ipv4(skb, dev); 908 break; 909 case htons(ETH_P_IPV6): 910 ret = ip6gre_xmit_ipv6(skb, dev); 911 break; 912 default: 913 ret = ip6gre_xmit_other(skb, dev); 914 break; 915 } 916 917 if (ret < 0) 918 goto tx_err; 919 920 return NETDEV_TX_OK; 921 922 tx_err: 923 stats->tx_errors++; 924 stats->tx_dropped++; 925 kfree_skb(skb); 926 return NETDEV_TX_OK; 927 } 928 929 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 930 { 931 struct net_device *dev = t->dev; 932 struct __ip6_tnl_parm *p = &t->parms; 933 struct flowi6 *fl6 = &t->fl.u.ip6; 934 int addend = sizeof(struct ipv6hdr) + 4; 935 936 if (dev->type != ARPHRD_ETHER) { 937 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 938 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 939 } 940 941 /* Set up flowi template */ 942 fl6->saddr = p->laddr; 943 fl6->daddr = p->raddr; 944 fl6->flowi6_oif = p->link; 945 fl6->flowlabel = 0; 946 947 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 948 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 949 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 950 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 951 952 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 953 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 954 955 if (p->flags&IP6_TNL_F_CAP_XMIT && 956 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 957 dev->flags |= IFF_POINTOPOINT; 958 else 959 dev->flags &= ~IFF_POINTOPOINT; 960 961 /* Precalculate GRE options length */ 962 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 963 if (t->parms.o_flags&GRE_CSUM) 964 addend += 4; 965 if (t->parms.o_flags&GRE_KEY) 966 addend += 4; 967 if (t->parms.o_flags&GRE_SEQ) 968 addend += 4; 969 } 970 t->hlen = addend; 971 972 if (p->flags & IP6_TNL_F_CAP_XMIT) { 973 int strict = (ipv6_addr_type(&p->raddr) & 974 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 975 976 struct rt6_info *rt = rt6_lookup(t->net, 977 &p->raddr, &p->laddr, 978 p->link, strict); 979 980 if (!rt) 981 return; 982 983 if (rt->dst.dev) { 984 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 985 986 if (set_mtu) { 987 dev->mtu = rt->dst.dev->mtu - addend; 988 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 989 dev->mtu -= 8; 990 991 if (dev->mtu < IPV6_MIN_MTU) 992 dev->mtu = IPV6_MIN_MTU; 993 } 994 } 995 ip6_rt_put(rt); 996 } 997 } 998 999 static int ip6gre_tnl_change(struct ip6_tnl *t, 1000 const struct __ip6_tnl_parm *p, int set_mtu) 1001 { 1002 t->parms.laddr = p->laddr; 1003 t->parms.raddr = p->raddr; 1004 t->parms.flags = p->flags; 1005 t->parms.hop_limit = p->hop_limit; 1006 t->parms.encap_limit = p->encap_limit; 1007 t->parms.flowinfo = p->flowinfo; 1008 t->parms.link = p->link; 1009 t->parms.proto = p->proto; 1010 t->parms.i_key = p->i_key; 1011 t->parms.o_key = p->o_key; 1012 t->parms.i_flags = p->i_flags; 1013 t->parms.o_flags = p->o_flags; 1014 dst_cache_reset(&t->dst_cache); 1015 ip6gre_tnl_link_config(t, set_mtu); 1016 return 0; 1017 } 1018 1019 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1020 const struct ip6_tnl_parm2 *u) 1021 { 1022 p->laddr = u->laddr; 1023 p->raddr = u->raddr; 1024 p->flags = u->flags; 1025 p->hop_limit = u->hop_limit; 1026 p->encap_limit = u->encap_limit; 1027 p->flowinfo = u->flowinfo; 1028 p->link = u->link; 1029 p->i_key = u->i_key; 1030 p->o_key = u->o_key; 1031 p->i_flags = u->i_flags; 1032 p->o_flags = u->o_flags; 1033 memcpy(p->name, u->name, sizeof(u->name)); 1034 } 1035 1036 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1037 const struct __ip6_tnl_parm *p) 1038 { 1039 u->proto = IPPROTO_GRE; 1040 u->laddr = p->laddr; 1041 u->raddr = p->raddr; 1042 u->flags = p->flags; 1043 u->hop_limit = p->hop_limit; 1044 u->encap_limit = p->encap_limit; 1045 u->flowinfo = p->flowinfo; 1046 u->link = p->link; 1047 u->i_key = p->i_key; 1048 u->o_key = p->o_key; 1049 u->i_flags = p->i_flags; 1050 u->o_flags = p->o_flags; 1051 memcpy(u->name, p->name, sizeof(u->name)); 1052 } 1053 1054 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1055 struct ifreq *ifr, int cmd) 1056 { 1057 int err = 0; 1058 struct ip6_tnl_parm2 p; 1059 struct __ip6_tnl_parm p1; 1060 struct ip6_tnl *t = netdev_priv(dev); 1061 struct net *net = t->net; 1062 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1063 1064 switch (cmd) { 1065 case SIOCGETTUNNEL: 1066 if (dev == ign->fb_tunnel_dev) { 1067 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1068 err = -EFAULT; 1069 break; 1070 } 1071 ip6gre_tnl_parm_from_user(&p1, &p); 1072 t = ip6gre_tunnel_locate(net, &p1, 0); 1073 if (!t) 1074 t = netdev_priv(dev); 1075 } 1076 memset(&p, 0, sizeof(p)); 1077 ip6gre_tnl_parm_to_user(&p, &t->parms); 1078 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1079 err = -EFAULT; 1080 break; 1081 1082 case SIOCADDTUNNEL: 1083 case SIOCCHGTUNNEL: 1084 err = -EPERM; 1085 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1086 goto done; 1087 1088 err = -EFAULT; 1089 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1090 goto done; 1091 1092 err = -EINVAL; 1093 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1094 goto done; 1095 1096 if (!(p.i_flags&GRE_KEY)) 1097 p.i_key = 0; 1098 if (!(p.o_flags&GRE_KEY)) 1099 p.o_key = 0; 1100 1101 ip6gre_tnl_parm_from_user(&p1, &p); 1102 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1103 1104 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1105 if (t) { 1106 if (t->dev != dev) { 1107 err = -EEXIST; 1108 break; 1109 } 1110 } else { 1111 t = netdev_priv(dev); 1112 1113 ip6gre_tunnel_unlink(ign, t); 1114 synchronize_net(); 1115 ip6gre_tnl_change(t, &p1, 1); 1116 ip6gre_tunnel_link(ign, t); 1117 netdev_state_change(dev); 1118 } 1119 } 1120 1121 if (t) { 1122 err = 0; 1123 1124 memset(&p, 0, sizeof(p)); 1125 ip6gre_tnl_parm_to_user(&p, &t->parms); 1126 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1127 err = -EFAULT; 1128 } else 1129 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1130 break; 1131 1132 case SIOCDELTUNNEL: 1133 err = -EPERM; 1134 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1135 goto done; 1136 1137 if (dev == ign->fb_tunnel_dev) { 1138 err = -EFAULT; 1139 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1140 goto done; 1141 err = -ENOENT; 1142 ip6gre_tnl_parm_from_user(&p1, &p); 1143 t = ip6gre_tunnel_locate(net, &p1, 0); 1144 if (!t) 1145 goto done; 1146 err = -EPERM; 1147 if (t == netdev_priv(ign->fb_tunnel_dev)) 1148 goto done; 1149 dev = t->dev; 1150 } 1151 unregister_netdevice(dev); 1152 err = 0; 1153 break; 1154 1155 default: 1156 err = -EINVAL; 1157 } 1158 1159 done: 1160 return err; 1161 } 1162 1163 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1164 { 1165 if (new_mtu < 68 || 1166 new_mtu > 0xFFF8 - dev->hard_header_len) 1167 return -EINVAL; 1168 dev->mtu = new_mtu; 1169 return 0; 1170 } 1171 1172 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1173 unsigned short type, 1174 const void *daddr, const void *saddr, unsigned int len) 1175 { 1176 struct ip6_tnl *t = netdev_priv(dev); 1177 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1178 __be16 *p = (__be16 *)(ipv6h+1); 1179 1180 ip6_flow_hdr(ipv6h, 0, 1181 ip6_make_flowlabel(dev_net(dev), skb, 1182 t->fl.u.ip6.flowlabel, true, 1183 &t->fl.u.ip6)); 1184 ipv6h->hop_limit = t->parms.hop_limit; 1185 ipv6h->nexthdr = NEXTHDR_GRE; 1186 ipv6h->saddr = t->parms.laddr; 1187 ipv6h->daddr = t->parms.raddr; 1188 1189 p[0] = t->parms.o_flags; 1190 p[1] = htons(type); 1191 1192 /* 1193 * Set the source hardware address. 1194 */ 1195 1196 if (saddr) 1197 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1198 if (daddr) 1199 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1200 if (!ipv6_addr_any(&ipv6h->daddr)) 1201 return t->hlen; 1202 1203 return -t->hlen; 1204 } 1205 1206 static const struct header_ops ip6gre_header_ops = { 1207 .create = ip6gre_header, 1208 }; 1209 1210 static const struct net_device_ops ip6gre_netdev_ops = { 1211 .ndo_init = ip6gre_tunnel_init, 1212 .ndo_uninit = ip6gre_tunnel_uninit, 1213 .ndo_start_xmit = ip6gre_tunnel_xmit, 1214 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1215 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1216 .ndo_get_stats64 = ip_tunnel_get_stats64, 1217 .ndo_get_iflink = ip6_tnl_get_iflink, 1218 }; 1219 1220 static void ip6gre_dev_free(struct net_device *dev) 1221 { 1222 struct ip6_tnl *t = netdev_priv(dev); 1223 1224 dst_cache_destroy(&t->dst_cache); 1225 free_percpu(dev->tstats); 1226 free_netdev(dev); 1227 } 1228 1229 static void ip6gre_tunnel_setup(struct net_device *dev) 1230 { 1231 struct ip6_tnl *t; 1232 1233 dev->netdev_ops = &ip6gre_netdev_ops; 1234 dev->destructor = ip6gre_dev_free; 1235 1236 dev->type = ARPHRD_IP6GRE; 1237 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1238 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1239 t = netdev_priv(dev); 1240 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1241 dev->mtu -= 8; 1242 dev->flags |= IFF_NOARP; 1243 dev->addr_len = sizeof(struct in6_addr); 1244 netif_keep_dst(dev); 1245 } 1246 1247 static int ip6gre_tunnel_init_common(struct net_device *dev) 1248 { 1249 struct ip6_tnl *tunnel; 1250 int ret; 1251 1252 tunnel = netdev_priv(dev); 1253 1254 tunnel->dev = dev; 1255 tunnel->net = dev_net(dev); 1256 strcpy(tunnel->parms.name, dev->name); 1257 1258 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1259 if (!dev->tstats) 1260 return -ENOMEM; 1261 1262 ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1263 if (ret) { 1264 free_percpu(dev->tstats); 1265 dev->tstats = NULL; 1266 return ret; 1267 } 1268 1269 return 0; 1270 } 1271 1272 static int ip6gre_tunnel_init(struct net_device *dev) 1273 { 1274 struct ip6_tnl *tunnel; 1275 int ret; 1276 1277 ret = ip6gre_tunnel_init_common(dev); 1278 if (ret) 1279 return ret; 1280 1281 tunnel = netdev_priv(dev); 1282 1283 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1284 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1285 1286 if (ipv6_addr_any(&tunnel->parms.raddr)) 1287 dev->header_ops = &ip6gre_header_ops; 1288 1289 return 0; 1290 } 1291 1292 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1293 { 1294 struct ip6_tnl *tunnel = netdev_priv(dev); 1295 1296 tunnel->dev = dev; 1297 tunnel->net = dev_net(dev); 1298 strcpy(tunnel->parms.name, dev->name); 1299 1300 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1301 1302 dev_hold(dev); 1303 } 1304 1305 1306 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1307 .handler = ip6gre_rcv, 1308 .err_handler = ip6gre_err, 1309 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1310 }; 1311 1312 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 1313 { 1314 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1315 struct net_device *dev, *aux; 1316 int prio; 1317 1318 for_each_netdev_safe(net, dev, aux) 1319 if (dev->rtnl_link_ops == &ip6gre_link_ops || 1320 dev->rtnl_link_ops == &ip6gre_tap_ops) 1321 unregister_netdevice_queue(dev, head); 1322 1323 for (prio = 0; prio < 4; prio++) { 1324 int h; 1325 for (h = 0; h < HASH_SIZE; h++) { 1326 struct ip6_tnl *t; 1327 1328 t = rtnl_dereference(ign->tunnels[prio][h]); 1329 1330 while (t) { 1331 /* If dev is in the same netns, it has already 1332 * been added to the list by the previous loop. 1333 */ 1334 if (!net_eq(dev_net(t->dev), net)) 1335 unregister_netdevice_queue(t->dev, 1336 head); 1337 t = rtnl_dereference(t->next); 1338 } 1339 } 1340 } 1341 } 1342 1343 static int __net_init ip6gre_init_net(struct net *net) 1344 { 1345 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1346 int err; 1347 1348 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1349 NET_NAME_UNKNOWN, 1350 ip6gre_tunnel_setup); 1351 if (!ign->fb_tunnel_dev) { 1352 err = -ENOMEM; 1353 goto err_alloc_dev; 1354 } 1355 dev_net_set(ign->fb_tunnel_dev, net); 1356 /* FB netdevice is special: we have one, and only one per netns. 1357 * Allowing to move it to another netns is clearly unsafe. 1358 */ 1359 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1360 1361 1362 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1363 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1364 1365 err = register_netdev(ign->fb_tunnel_dev); 1366 if (err) 1367 goto err_reg_dev; 1368 1369 rcu_assign_pointer(ign->tunnels_wc[0], 1370 netdev_priv(ign->fb_tunnel_dev)); 1371 return 0; 1372 1373 err_reg_dev: 1374 ip6gre_dev_free(ign->fb_tunnel_dev); 1375 err_alloc_dev: 1376 return err; 1377 } 1378 1379 static void __net_exit ip6gre_exit_net(struct net *net) 1380 { 1381 LIST_HEAD(list); 1382 1383 rtnl_lock(); 1384 ip6gre_destroy_tunnels(net, &list); 1385 unregister_netdevice_many(&list); 1386 rtnl_unlock(); 1387 } 1388 1389 static struct pernet_operations ip6gre_net_ops = { 1390 .init = ip6gre_init_net, 1391 .exit = ip6gre_exit_net, 1392 .id = &ip6gre_net_id, 1393 .size = sizeof(struct ip6gre_net), 1394 }; 1395 1396 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1397 { 1398 __be16 flags; 1399 1400 if (!data) 1401 return 0; 1402 1403 flags = 0; 1404 if (data[IFLA_GRE_IFLAGS]) 1405 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1406 if (data[IFLA_GRE_OFLAGS]) 1407 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1408 if (flags & (GRE_VERSION|GRE_ROUTING)) 1409 return -EINVAL; 1410 1411 return 0; 1412 } 1413 1414 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1415 { 1416 struct in6_addr daddr; 1417 1418 if (tb[IFLA_ADDRESS]) { 1419 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1420 return -EINVAL; 1421 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1422 return -EADDRNOTAVAIL; 1423 } 1424 1425 if (!data) 1426 goto out; 1427 1428 if (data[IFLA_GRE_REMOTE]) { 1429 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1430 if (ipv6_addr_any(&daddr)) 1431 return -EINVAL; 1432 } 1433 1434 out: 1435 return ip6gre_tunnel_validate(tb, data); 1436 } 1437 1438 1439 static void ip6gre_netlink_parms(struct nlattr *data[], 1440 struct __ip6_tnl_parm *parms) 1441 { 1442 memset(parms, 0, sizeof(*parms)); 1443 1444 if (!data) 1445 return; 1446 1447 if (data[IFLA_GRE_LINK]) 1448 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1449 1450 if (data[IFLA_GRE_IFLAGS]) 1451 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1452 1453 if (data[IFLA_GRE_OFLAGS]) 1454 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1455 1456 if (data[IFLA_GRE_IKEY]) 1457 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1458 1459 if (data[IFLA_GRE_OKEY]) 1460 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1461 1462 if (data[IFLA_GRE_LOCAL]) 1463 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]); 1464 1465 if (data[IFLA_GRE_REMOTE]) 1466 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1467 1468 if (data[IFLA_GRE_TTL]) 1469 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1470 1471 if (data[IFLA_GRE_ENCAP_LIMIT]) 1472 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1473 1474 if (data[IFLA_GRE_FLOWINFO]) 1475 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1476 1477 if (data[IFLA_GRE_FLAGS]) 1478 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1479 } 1480 1481 static int ip6gre_tap_init(struct net_device *dev) 1482 { 1483 struct ip6_tnl *tunnel; 1484 int ret; 1485 1486 ret = ip6gre_tunnel_init_common(dev); 1487 if (ret) 1488 return ret; 1489 1490 tunnel = netdev_priv(dev); 1491 1492 ip6gre_tnl_link_config(tunnel, 1); 1493 1494 return 0; 1495 } 1496 1497 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1498 .ndo_init = ip6gre_tap_init, 1499 .ndo_uninit = ip6gre_tunnel_uninit, 1500 .ndo_start_xmit = ip6gre_tunnel_xmit, 1501 .ndo_set_mac_address = eth_mac_addr, 1502 .ndo_validate_addr = eth_validate_addr, 1503 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1504 .ndo_get_stats64 = ip_tunnel_get_stats64, 1505 .ndo_get_iflink = ip6_tnl_get_iflink, 1506 }; 1507 1508 static void ip6gre_tap_setup(struct net_device *dev) 1509 { 1510 1511 ether_setup(dev); 1512 1513 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1514 dev->destructor = ip6gre_dev_free; 1515 1516 dev->features |= NETIF_F_NETNS_LOCAL; 1517 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1518 } 1519 1520 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1521 struct nlattr *tb[], struct nlattr *data[]) 1522 { 1523 struct ip6_tnl *nt; 1524 struct net *net = dev_net(dev); 1525 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1526 int err; 1527 1528 nt = netdev_priv(dev); 1529 ip6gre_netlink_parms(data, &nt->parms); 1530 1531 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1532 return -EEXIST; 1533 1534 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1535 eth_hw_addr_random(dev); 1536 1537 nt->dev = dev; 1538 nt->net = dev_net(dev); 1539 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1540 1541 /* Can use a lockless transmit, unless we generate output sequences */ 1542 if (!(nt->parms.o_flags & GRE_SEQ)) 1543 dev->features |= NETIF_F_LLTX; 1544 1545 err = register_netdevice(dev); 1546 if (err) 1547 goto out; 1548 1549 dev_hold(dev); 1550 ip6gre_tunnel_link(ign, nt); 1551 1552 out: 1553 return err; 1554 } 1555 1556 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1557 struct nlattr *data[]) 1558 { 1559 struct ip6_tnl *t, *nt = netdev_priv(dev); 1560 struct net *net = nt->net; 1561 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1562 struct __ip6_tnl_parm p; 1563 1564 if (dev == ign->fb_tunnel_dev) 1565 return -EINVAL; 1566 1567 ip6gre_netlink_parms(data, &p); 1568 1569 t = ip6gre_tunnel_locate(net, &p, 0); 1570 1571 if (t) { 1572 if (t->dev != dev) 1573 return -EEXIST; 1574 } else { 1575 t = nt; 1576 } 1577 1578 ip6gre_tunnel_unlink(ign, t); 1579 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1580 ip6gre_tunnel_link(ign, t); 1581 return 0; 1582 } 1583 1584 static void ip6gre_dellink(struct net_device *dev, struct list_head *head) 1585 { 1586 struct net *net = dev_net(dev); 1587 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1588 1589 if (dev != ign->fb_tunnel_dev) 1590 unregister_netdevice_queue(dev, head); 1591 } 1592 1593 static size_t ip6gre_get_size(const struct net_device *dev) 1594 { 1595 return 1596 /* IFLA_GRE_LINK */ 1597 nla_total_size(4) + 1598 /* IFLA_GRE_IFLAGS */ 1599 nla_total_size(2) + 1600 /* IFLA_GRE_OFLAGS */ 1601 nla_total_size(2) + 1602 /* IFLA_GRE_IKEY */ 1603 nla_total_size(4) + 1604 /* IFLA_GRE_OKEY */ 1605 nla_total_size(4) + 1606 /* IFLA_GRE_LOCAL */ 1607 nla_total_size(sizeof(struct in6_addr)) + 1608 /* IFLA_GRE_REMOTE */ 1609 nla_total_size(sizeof(struct in6_addr)) + 1610 /* IFLA_GRE_TTL */ 1611 nla_total_size(1) + 1612 /* IFLA_GRE_TOS */ 1613 nla_total_size(1) + 1614 /* IFLA_GRE_ENCAP_LIMIT */ 1615 nla_total_size(1) + 1616 /* IFLA_GRE_FLOWINFO */ 1617 nla_total_size(4) + 1618 /* IFLA_GRE_FLAGS */ 1619 nla_total_size(4) + 1620 0; 1621 } 1622 1623 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1624 { 1625 struct ip6_tnl *t = netdev_priv(dev); 1626 struct __ip6_tnl_parm *p = &t->parms; 1627 1628 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1629 nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) || 1630 nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) || 1631 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1632 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1633 nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) || 1634 nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) || 1635 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1636 /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/ 1637 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1638 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1639 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags)) 1640 goto nla_put_failure; 1641 return 0; 1642 1643 nla_put_failure: 1644 return -EMSGSIZE; 1645 } 1646 1647 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1648 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1649 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1650 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1651 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1652 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1653 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1654 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1655 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1656 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1657 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1658 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1659 }; 1660 1661 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1662 .kind = "ip6gre", 1663 .maxtype = IFLA_GRE_MAX, 1664 .policy = ip6gre_policy, 1665 .priv_size = sizeof(struct ip6_tnl), 1666 .setup = ip6gre_tunnel_setup, 1667 .validate = ip6gre_tunnel_validate, 1668 .newlink = ip6gre_newlink, 1669 .changelink = ip6gre_changelink, 1670 .dellink = ip6gre_dellink, 1671 .get_size = ip6gre_get_size, 1672 .fill_info = ip6gre_fill_info, 1673 .get_link_net = ip6_tnl_get_link_net, 1674 }; 1675 1676 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1677 .kind = "ip6gretap", 1678 .maxtype = IFLA_GRE_MAX, 1679 .policy = ip6gre_policy, 1680 .priv_size = sizeof(struct ip6_tnl), 1681 .setup = ip6gre_tap_setup, 1682 .validate = ip6gre_tap_validate, 1683 .newlink = ip6gre_newlink, 1684 .changelink = ip6gre_changelink, 1685 .get_size = ip6gre_get_size, 1686 .fill_info = ip6gre_fill_info, 1687 .get_link_net = ip6_tnl_get_link_net, 1688 }; 1689 1690 /* 1691 * And now the modules code and kernel interface. 1692 */ 1693 1694 static int __init ip6gre_init(void) 1695 { 1696 int err; 1697 1698 pr_info("GRE over IPv6 tunneling driver\n"); 1699 1700 err = register_pernet_device(&ip6gre_net_ops); 1701 if (err < 0) 1702 return err; 1703 1704 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1705 if (err < 0) { 1706 pr_info("%s: can't add protocol\n", __func__); 1707 goto add_proto_failed; 1708 } 1709 1710 err = rtnl_link_register(&ip6gre_link_ops); 1711 if (err < 0) 1712 goto rtnl_link_failed; 1713 1714 err = rtnl_link_register(&ip6gre_tap_ops); 1715 if (err < 0) 1716 goto tap_ops_failed; 1717 1718 out: 1719 return err; 1720 1721 tap_ops_failed: 1722 rtnl_link_unregister(&ip6gre_link_ops); 1723 rtnl_link_failed: 1724 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1725 add_proto_failed: 1726 unregister_pernet_device(&ip6gre_net_ops); 1727 goto out; 1728 } 1729 1730 static void __exit ip6gre_fini(void) 1731 { 1732 rtnl_link_unregister(&ip6gre_tap_ops); 1733 rtnl_link_unregister(&ip6gre_link_ops); 1734 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1735 unregister_pernet_device(&ip6gre_net_ops); 1736 } 1737 1738 module_init(ip6gre_init); 1739 module_exit(ip6gre_fini); 1740 MODULE_LICENSE("GPL"); 1741 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1742 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1743 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1744 MODULE_ALIAS_RTNL_LINK("ip6gretap"); 1745 MODULE_ALIAS_NETDEV("ip6gre0"); 1746