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/mroute.h> 28 #include <linux/init.h> 29 #include <linux/in6.h> 30 #include <linux/inetdevice.h> 31 #include <linux/igmp.h> 32 #include <linux/netfilter_ipv4.h> 33 #include <linux/etherdevice.h> 34 #include <linux/if_ether.h> 35 #include <linux/hash.h> 36 #include <linux/if_tunnel.h> 37 #include <linux/ip6_tunnel.h> 38 39 #include <net/sock.h> 40 #include <net/ip.h> 41 #include <net/ip_tunnels.h> 42 #include <net/icmp.h> 43 #include <net/protocol.h> 44 #include <net/addrconf.h> 45 #include <net/arp.h> 46 #include <net/checksum.h> 47 #include <net/dsfield.h> 48 #include <net/inet_ecn.h> 49 #include <net/xfrm.h> 50 #include <net/net_namespace.h> 51 #include <net/netns/generic.h> 52 #include <net/rtnetlink.h> 53 54 #include <net/ipv6.h> 55 #include <net/ip6_fib.h> 56 #include <net/ip6_route.h> 57 #include <net/ip6_tunnel.h> 58 59 60 static bool log_ecn_error = true; 61 module_param(log_ecn_error, bool, 0644); 62 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 63 64 #define HASH_SIZE_SHIFT 5 65 #define HASH_SIZE (1 << HASH_SIZE_SHIFT) 66 67 static int ip6gre_net_id __read_mostly; 68 struct ip6gre_net { 69 struct ip6_tnl __rcu *tunnels[4][HASH_SIZE]; 70 71 struct net_device *fb_tunnel_dev; 72 }; 73 74 static struct rtnl_link_ops ip6gre_link_ops __read_mostly; 75 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly; 76 static int ip6gre_tunnel_init(struct net_device *dev); 77 static void ip6gre_tunnel_setup(struct net_device *dev); 78 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t); 79 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu); 80 81 /* Tunnel hash table */ 82 83 /* 84 4 hash tables: 85 86 3: (remote,local) 87 2: (remote,*) 88 1: (*,local) 89 0: (*,*) 90 91 We require exact key match i.e. if a key is present in packet 92 it will match only tunnel with the same key; if it is not present, 93 it will match only keyless tunnel. 94 95 All keysless packets, if not matched configured keyless tunnels 96 will match fallback tunnel. 97 */ 98 99 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 1)) 100 static u32 HASH_ADDR(const struct in6_addr *addr) 101 { 102 u32 hash = ipv6_addr_hash(addr); 103 104 return hash_32(hash, HASH_SIZE_SHIFT); 105 } 106 107 #define tunnels_r_l tunnels[3] 108 #define tunnels_r tunnels[2] 109 #define tunnels_l tunnels[1] 110 #define tunnels_wc tunnels[0] 111 112 /* Given src, dst and key, find appropriate for input tunnel. */ 113 114 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev, 115 const struct in6_addr *remote, const struct in6_addr *local, 116 __be32 key, __be16 gre_proto) 117 { 118 struct net *net = dev_net(dev); 119 int link = dev->ifindex; 120 unsigned int h0 = HASH_ADDR(remote); 121 unsigned int h1 = HASH_KEY(key); 122 struct ip6_tnl *t, *cand = NULL; 123 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 124 int dev_type = (gre_proto == htons(ETH_P_TEB)) ? 125 ARPHRD_ETHER : ARPHRD_IP6GRE; 126 int score, cand_score = 4; 127 128 for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) { 129 if (!ipv6_addr_equal(local, &t->parms.laddr) || 130 !ipv6_addr_equal(remote, &t->parms.raddr) || 131 key != t->parms.i_key || 132 !(t->dev->flags & IFF_UP)) 133 continue; 134 135 if (t->dev->type != ARPHRD_IP6GRE && 136 t->dev->type != dev_type) 137 continue; 138 139 score = 0; 140 if (t->parms.link != link) 141 score |= 1; 142 if (t->dev->type != dev_type) 143 score |= 2; 144 if (score == 0) 145 return t; 146 147 if (score < cand_score) { 148 cand = t; 149 cand_score = score; 150 } 151 } 152 153 for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) { 154 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 155 key != t->parms.i_key || 156 !(t->dev->flags & IFF_UP)) 157 continue; 158 159 if (t->dev->type != ARPHRD_IP6GRE && 160 t->dev->type != dev_type) 161 continue; 162 163 score = 0; 164 if (t->parms.link != link) 165 score |= 1; 166 if (t->dev->type != dev_type) 167 score |= 2; 168 if (score == 0) 169 return t; 170 171 if (score < cand_score) { 172 cand = t; 173 cand_score = score; 174 } 175 } 176 177 for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) { 178 if ((!ipv6_addr_equal(local, &t->parms.laddr) && 179 (!ipv6_addr_equal(local, &t->parms.raddr) || 180 !ipv6_addr_is_multicast(local))) || 181 key != t->parms.i_key || 182 !(t->dev->flags & IFF_UP)) 183 continue; 184 185 if (t->dev->type != ARPHRD_IP6GRE && 186 t->dev->type != dev_type) 187 continue; 188 189 score = 0; 190 if (t->parms.link != link) 191 score |= 1; 192 if (t->dev->type != dev_type) 193 score |= 2; 194 if (score == 0) 195 return t; 196 197 if (score < cand_score) { 198 cand = t; 199 cand_score = score; 200 } 201 } 202 203 for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) { 204 if (t->parms.i_key != key || 205 !(t->dev->flags & IFF_UP)) 206 continue; 207 208 if (t->dev->type != ARPHRD_IP6GRE && 209 t->dev->type != dev_type) 210 continue; 211 212 score = 0; 213 if (t->parms.link != link) 214 score |= 1; 215 if (t->dev->type != dev_type) 216 score |= 2; 217 if (score == 0) 218 return t; 219 220 if (score < cand_score) { 221 cand = t; 222 cand_score = score; 223 } 224 } 225 226 if (cand) 227 return cand; 228 229 dev = ign->fb_tunnel_dev; 230 if (dev->flags & IFF_UP) 231 return netdev_priv(dev); 232 233 return NULL; 234 } 235 236 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign, 237 const struct __ip6_tnl_parm *p) 238 { 239 const struct in6_addr *remote = &p->raddr; 240 const struct in6_addr *local = &p->laddr; 241 unsigned int h = HASH_KEY(p->i_key); 242 int prio = 0; 243 244 if (!ipv6_addr_any(local)) 245 prio |= 1; 246 if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) { 247 prio |= 2; 248 h ^= HASH_ADDR(remote); 249 } 250 251 return &ign->tunnels[prio][h]; 252 } 253 254 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign, 255 const struct ip6_tnl *t) 256 { 257 return __ip6gre_bucket(ign, &t->parms); 258 } 259 260 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t) 261 { 262 struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t); 263 264 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 265 rcu_assign_pointer(*tp, t); 266 } 267 268 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t) 269 { 270 struct ip6_tnl __rcu **tp; 271 struct ip6_tnl *iter; 272 273 for (tp = ip6gre_bucket(ign, t); 274 (iter = rtnl_dereference(*tp)) != NULL; 275 tp = &iter->next) { 276 if (t == iter) { 277 rcu_assign_pointer(*tp, t->next); 278 break; 279 } 280 } 281 } 282 283 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net, 284 const struct __ip6_tnl_parm *parms, 285 int type) 286 { 287 const struct in6_addr *remote = &parms->raddr; 288 const struct in6_addr *local = &parms->laddr; 289 __be32 key = parms->i_key; 290 int link = parms->link; 291 struct ip6_tnl *t; 292 struct ip6_tnl __rcu **tp; 293 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 294 295 for (tp = __ip6gre_bucket(ign, parms); 296 (t = rtnl_dereference(*tp)) != NULL; 297 tp = &t->next) 298 if (ipv6_addr_equal(local, &t->parms.laddr) && 299 ipv6_addr_equal(remote, &t->parms.raddr) && 300 key == t->parms.i_key && 301 link == t->parms.link && 302 type == t->dev->type) 303 break; 304 305 return t; 306 } 307 308 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, 309 const struct __ip6_tnl_parm *parms, int create) 310 { 311 struct ip6_tnl *t, *nt; 312 struct net_device *dev; 313 char name[IFNAMSIZ]; 314 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 315 316 t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE); 317 if (t && create) 318 return NULL; 319 if (t || !create) 320 return t; 321 322 if (parms->name[0]) 323 strlcpy(name, parms->name, IFNAMSIZ); 324 else 325 strcpy(name, "ip6gre%d"); 326 327 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 328 ip6gre_tunnel_setup); 329 if (!dev) 330 return NULL; 331 332 dev_net_set(dev, net); 333 334 nt = netdev_priv(dev); 335 nt->parms = *parms; 336 dev->rtnl_link_ops = &ip6gre_link_ops; 337 338 nt->dev = dev; 339 nt->net = dev_net(dev); 340 ip6gre_tnl_link_config(nt, 1); 341 342 if (register_netdevice(dev) < 0) 343 goto failed_free; 344 345 /* Can use a lockless transmit, unless we generate output sequences */ 346 if (!(nt->parms.o_flags & GRE_SEQ)) 347 dev->features |= NETIF_F_LLTX; 348 349 dev_hold(dev); 350 ip6gre_tunnel_link(ign, nt); 351 return nt; 352 353 failed_free: 354 free_netdev(dev); 355 return NULL; 356 } 357 358 static void ip6gre_tunnel_uninit(struct net_device *dev) 359 { 360 struct ip6_tnl *t = netdev_priv(dev); 361 struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id); 362 363 ip6gre_tunnel_unlink(ign, t); 364 ip6_tnl_dst_reset(t); 365 dev_put(dev); 366 } 367 368 369 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 370 u8 type, u8 code, int offset, __be32 info) 371 { 372 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 373 __be16 *p = (__be16 *)(skb->data + offset); 374 int grehlen = offset + 4; 375 struct ip6_tnl *t; 376 __be16 flags; 377 378 flags = p[0]; 379 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 380 if (flags&(GRE_VERSION|GRE_ROUTING)) 381 return; 382 if (flags&GRE_KEY) { 383 grehlen += 4; 384 if (flags&GRE_CSUM) 385 grehlen += 4; 386 } 387 } 388 389 /* If only 8 bytes returned, keyed message will be dropped here */ 390 if (!pskb_may_pull(skb, grehlen)) 391 return; 392 ipv6h = (const struct ipv6hdr *)skb->data; 393 p = (__be16 *)(skb->data + offset); 394 395 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 396 flags & GRE_KEY ? 397 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 398 p[1]); 399 if (!t) 400 return; 401 402 switch (type) { 403 __u32 teli; 404 struct ipv6_tlv_tnl_enc_lim *tel; 405 __u32 mtu; 406 case ICMPV6_DEST_UNREACH: 407 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 408 t->parms.name); 409 break; 410 case ICMPV6_TIME_EXCEED: 411 if (code == ICMPV6_EXC_HOPLIMIT) { 412 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 413 t->parms.name); 414 } 415 break; 416 case ICMPV6_PARAMPROB: 417 teli = 0; 418 if (code == ICMPV6_HDR_FIELD) 419 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 420 421 if (teli && teli == be32_to_cpu(info) - 2) { 422 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 423 if (tel->encap_limit == 0) { 424 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 425 t->parms.name); 426 } 427 } else { 428 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 429 t->parms.name); 430 } 431 break; 432 case ICMPV6_PKT_TOOBIG: 433 mtu = be32_to_cpu(info) - offset; 434 if (mtu < IPV6_MIN_MTU) 435 mtu = IPV6_MIN_MTU; 436 t->dev->mtu = mtu; 437 break; 438 } 439 440 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 441 t->err_count++; 442 else 443 t->err_count = 1; 444 t->err_time = jiffies; 445 } 446 447 static int ip6gre_rcv(struct sk_buff *skb) 448 { 449 const struct ipv6hdr *ipv6h; 450 u8 *h; 451 __be16 flags; 452 __sum16 csum = 0; 453 __be32 key = 0; 454 u32 seqno = 0; 455 struct ip6_tnl *tunnel; 456 int offset = 4; 457 __be16 gre_proto; 458 int err; 459 460 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 461 goto drop; 462 463 ipv6h = ipv6_hdr(skb); 464 h = skb->data; 465 flags = *(__be16 *)h; 466 467 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 468 /* - Version must be 0. 469 - We do not support routing headers. 470 */ 471 if (flags&(GRE_VERSION|GRE_ROUTING)) 472 goto drop; 473 474 if (flags&GRE_CSUM) { 475 csum = skb_checksum_simple_validate(skb); 476 offset += 4; 477 } 478 if (flags&GRE_KEY) { 479 key = *(__be32 *)(h + offset); 480 offset += 4; 481 } 482 if (flags&GRE_SEQ) { 483 seqno = ntohl(*(__be32 *)(h + offset)); 484 offset += 4; 485 } 486 } 487 488 gre_proto = *(__be16 *)(h + 2); 489 490 tunnel = ip6gre_tunnel_lookup(skb->dev, 491 &ipv6h->saddr, &ipv6h->daddr, key, 492 gre_proto); 493 if (tunnel) { 494 struct pcpu_sw_netstats *tstats; 495 496 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 497 goto drop; 498 499 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 500 tunnel->dev->stats.rx_dropped++; 501 goto drop; 502 } 503 504 skb->protocol = gre_proto; 505 /* WCCP version 1 and 2 protocol decoding. 506 * - Change protocol to IPv6 507 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 508 */ 509 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 510 skb->protocol = htons(ETH_P_IPV6); 511 if ((*(h + offset) & 0xF0) != 0x40) 512 offset += 4; 513 } 514 515 skb->mac_header = skb->network_header; 516 __pskb_pull(skb, offset); 517 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 518 519 if (((flags&GRE_CSUM) && csum) || 520 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 521 tunnel->dev->stats.rx_crc_errors++; 522 tunnel->dev->stats.rx_errors++; 523 goto drop; 524 } 525 if (tunnel->parms.i_flags&GRE_SEQ) { 526 if (!(flags&GRE_SEQ) || 527 (tunnel->i_seqno && 528 (s32)(seqno - tunnel->i_seqno) < 0)) { 529 tunnel->dev->stats.rx_fifo_errors++; 530 tunnel->dev->stats.rx_errors++; 531 goto drop; 532 } 533 tunnel->i_seqno = seqno + 1; 534 } 535 536 /* Warning: All skb pointers will be invalidated! */ 537 if (tunnel->dev->type == ARPHRD_ETHER) { 538 if (!pskb_may_pull(skb, ETH_HLEN)) { 539 tunnel->dev->stats.rx_length_errors++; 540 tunnel->dev->stats.rx_errors++; 541 goto drop; 542 } 543 544 ipv6h = ipv6_hdr(skb); 545 skb->protocol = eth_type_trans(skb, tunnel->dev); 546 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 547 } 548 549 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 550 551 skb_reset_network_header(skb); 552 553 err = IP6_ECN_decapsulate(ipv6h, skb); 554 if (unlikely(err)) { 555 if (log_ecn_error) 556 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 557 &ipv6h->saddr, 558 ipv6_get_dsfield(ipv6h)); 559 if (err > 1) { 560 ++tunnel->dev->stats.rx_frame_errors; 561 ++tunnel->dev->stats.rx_errors; 562 goto drop; 563 } 564 } 565 566 tstats = this_cpu_ptr(tunnel->dev->tstats); 567 u64_stats_update_begin(&tstats->syncp); 568 tstats->rx_packets++; 569 tstats->rx_bytes += skb->len; 570 u64_stats_update_end(&tstats->syncp); 571 572 netif_rx(skb); 573 574 return 0; 575 } 576 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 577 578 drop: 579 kfree_skb(skb); 580 return 0; 581 } 582 583 struct ipv6_tel_txoption { 584 struct ipv6_txoptions ops; 585 __u8 dst_opt[8]; 586 }; 587 588 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 589 { 590 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 591 592 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 593 opt->dst_opt[3] = 1; 594 opt->dst_opt[4] = encap_limit; 595 opt->dst_opt[5] = IPV6_TLV_PADN; 596 opt->dst_opt[6] = 1; 597 598 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 599 opt->ops.opt_nflen = 8; 600 } 601 602 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 603 struct net_device *dev, 604 __u8 dsfield, 605 struct flowi6 *fl6, 606 int encap_limit, 607 __u32 *pmtu) 608 { 609 struct ip6_tnl *tunnel = netdev_priv(dev); 610 struct net *net = tunnel->net; 611 struct net_device *tdev; /* Device to other host */ 612 struct ipv6hdr *ipv6h; /* Our new IP header */ 613 unsigned int max_headroom = 0; /* The extra header space needed */ 614 int gre_hlen; 615 struct ipv6_tel_txoption opt; 616 int mtu; 617 struct dst_entry *dst = NULL, *ndst = NULL; 618 struct net_device_stats *stats = &tunnel->dev->stats; 619 int err = -1; 620 u8 proto; 621 struct sk_buff *new_skb; 622 __be16 protocol; 623 624 if (dev->type == ARPHRD_ETHER) 625 IPCB(skb)->flags = 0; 626 627 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 628 gre_hlen = 0; 629 ipv6h = (struct ipv6hdr *)skb->data; 630 fl6->daddr = ipv6h->daddr; 631 } else { 632 gre_hlen = tunnel->hlen; 633 fl6->daddr = tunnel->parms.raddr; 634 } 635 636 if (!fl6->flowi6_mark) 637 dst = ip6_tnl_dst_get(tunnel); 638 639 if (!dst) { 640 dst = ip6_route_output(net, NULL, fl6); 641 642 if (dst->error) 643 goto tx_err_link_failure; 644 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); 645 if (IS_ERR(dst)) { 646 err = PTR_ERR(dst); 647 dst = NULL; 648 goto tx_err_link_failure; 649 } 650 ndst = dst; 651 } 652 653 tdev = dst->dev; 654 655 if (tdev == dev) { 656 stats->collisions++; 657 net_warn_ratelimited("%s: Local routing loop detected!\n", 658 tunnel->parms.name); 659 goto tx_err_dst_release; 660 } 661 662 mtu = dst_mtu(dst) - sizeof(*ipv6h); 663 if (encap_limit >= 0) { 664 max_headroom += 8; 665 mtu -= 8; 666 } 667 if (mtu < IPV6_MIN_MTU) 668 mtu = IPV6_MIN_MTU; 669 if (skb_dst(skb)) 670 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 671 if (skb->len > mtu) { 672 *pmtu = mtu; 673 err = -EMSGSIZE; 674 goto tx_err_dst_release; 675 } 676 677 if (tunnel->err_count > 0) { 678 if (time_before(jiffies, 679 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 680 tunnel->err_count--; 681 682 dst_link_failure(skb); 683 } else 684 tunnel->err_count = 0; 685 } 686 687 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); 688 689 max_headroom += LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; 690 691 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 692 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 693 new_skb = skb_realloc_headroom(skb, max_headroom); 694 if (max_headroom > dev->needed_headroom) 695 dev->needed_headroom = max_headroom; 696 if (!new_skb) 697 goto tx_err_dst_release; 698 699 if (skb->sk) 700 skb_set_owner_w(new_skb, skb->sk); 701 consume_skb(skb); 702 skb = new_skb; 703 } 704 705 if (!fl6->flowi6_mark && ndst) 706 ip6_tnl_dst_set(tunnel, ndst); 707 skb_dst_set(skb, dst); 708 709 proto = NEXTHDR_GRE; 710 if (encap_limit >= 0) { 711 init_tel_txopt(&opt, encap_limit); 712 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 713 } 714 715 if (likely(!skb->encapsulation)) { 716 skb_reset_inner_headers(skb); 717 skb->encapsulation = 1; 718 } 719 720 skb_push(skb, gre_hlen); 721 skb_reset_network_header(skb); 722 skb_set_transport_header(skb, sizeof(*ipv6h)); 723 724 /* 725 * Push down and install the IP header. 726 */ 727 ipv6h = ipv6_hdr(skb); 728 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), 729 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); 730 ipv6h->hop_limit = tunnel->parms.hop_limit; 731 ipv6h->nexthdr = proto; 732 ipv6h->saddr = fl6->saddr; 733 ipv6h->daddr = fl6->daddr; 734 735 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 736 protocol = (dev->type == ARPHRD_ETHER) ? 737 htons(ETH_P_TEB) : skb->protocol; 738 ((__be16 *)(ipv6h + 1))[1] = protocol; 739 740 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 741 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 742 743 if (tunnel->parms.o_flags&GRE_SEQ) { 744 ++tunnel->o_seqno; 745 *ptr = htonl(tunnel->o_seqno); 746 ptr--; 747 } 748 if (tunnel->parms.o_flags&GRE_KEY) { 749 *ptr = tunnel->parms.o_key; 750 ptr--; 751 } 752 if (tunnel->parms.o_flags&GRE_CSUM) { 753 *ptr = 0; 754 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 755 skb->len - sizeof(struct ipv6hdr)); 756 } 757 } 758 759 skb_set_inner_protocol(skb, protocol); 760 761 ip6tunnel_xmit(NULL, skb, dev); 762 return 0; 763 tx_err_link_failure: 764 stats->tx_carrier_errors++; 765 dst_link_failure(skb); 766 tx_err_dst_release: 767 dst_release(dst); 768 return err; 769 } 770 771 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 772 { 773 struct ip6_tnl *t = netdev_priv(dev); 774 const struct iphdr *iph = ip_hdr(skb); 775 int encap_limit = -1; 776 struct flowi6 fl6; 777 __u8 dsfield; 778 __u32 mtu; 779 int err; 780 781 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 782 encap_limit = t->parms.encap_limit; 783 784 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 785 fl6.flowi6_proto = IPPROTO_GRE; 786 787 dsfield = ipv4_get_dsfield(iph); 788 789 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 790 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 791 & IPV6_TCLASS_MASK; 792 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 793 fl6.flowi6_mark = skb->mark; 794 795 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 796 if (err != 0) { 797 /* XXX: send ICMP error even if DF is not set. */ 798 if (err == -EMSGSIZE) 799 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 800 htonl(mtu)); 801 return -1; 802 } 803 804 return 0; 805 } 806 807 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 808 { 809 struct ip6_tnl *t = netdev_priv(dev); 810 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 811 int encap_limit = -1; 812 __u16 offset; 813 struct flowi6 fl6; 814 __u8 dsfield; 815 __u32 mtu; 816 int err; 817 818 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 819 return -1; 820 821 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 822 if (offset > 0) { 823 struct ipv6_tlv_tnl_enc_lim *tel; 824 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 825 if (tel->encap_limit == 0) { 826 icmpv6_send(skb, ICMPV6_PARAMPROB, 827 ICMPV6_HDR_FIELD, offset + 2); 828 return -1; 829 } 830 encap_limit = tel->encap_limit - 1; 831 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 832 encap_limit = t->parms.encap_limit; 833 834 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 835 fl6.flowi6_proto = IPPROTO_GRE; 836 837 dsfield = ipv6_get_dsfield(ipv6h); 838 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 839 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 840 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 841 fl6.flowlabel |= ip6_flowlabel(ipv6h); 842 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 843 fl6.flowi6_mark = skb->mark; 844 845 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 846 if (err != 0) { 847 if (err == -EMSGSIZE) 848 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 849 return -1; 850 } 851 852 return 0; 853 } 854 855 /** 856 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 857 * @t: the outgoing tunnel device 858 * @hdr: IPv6 header from the incoming packet 859 * 860 * Description: 861 * Avoid trivial tunneling loop by checking that tunnel exit-point 862 * doesn't match source of incoming packet. 863 * 864 * Return: 865 * 1 if conflict, 866 * 0 else 867 **/ 868 869 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 870 const struct ipv6hdr *hdr) 871 { 872 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 873 } 874 875 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 876 { 877 struct ip6_tnl *t = netdev_priv(dev); 878 int encap_limit = -1; 879 struct flowi6 fl6; 880 __u32 mtu; 881 int err; 882 883 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 884 encap_limit = t->parms.encap_limit; 885 886 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 887 fl6.flowi6_proto = skb->protocol; 888 889 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 890 891 return err; 892 } 893 894 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 895 struct net_device *dev) 896 { 897 struct ip6_tnl *t = netdev_priv(dev); 898 struct net_device_stats *stats = &t->dev->stats; 899 int ret; 900 901 if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr)) 902 goto tx_err; 903 904 switch (skb->protocol) { 905 case htons(ETH_P_IP): 906 ret = ip6gre_xmit_ipv4(skb, dev); 907 break; 908 case htons(ETH_P_IPV6): 909 ret = ip6gre_xmit_ipv6(skb, dev); 910 break; 911 default: 912 ret = ip6gre_xmit_other(skb, dev); 913 break; 914 } 915 916 if (ret < 0) 917 goto tx_err; 918 919 return NETDEV_TX_OK; 920 921 tx_err: 922 stats->tx_errors++; 923 stats->tx_dropped++; 924 kfree_skb(skb); 925 return NETDEV_TX_OK; 926 } 927 928 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 929 { 930 struct net_device *dev = t->dev; 931 struct __ip6_tnl_parm *p = &t->parms; 932 struct flowi6 *fl6 = &t->fl.u.ip6; 933 int addend = sizeof(struct ipv6hdr) + 4; 934 935 if (dev->type != ARPHRD_ETHER) { 936 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 937 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 938 } 939 940 /* Set up flowi template */ 941 fl6->saddr = p->laddr; 942 fl6->daddr = p->raddr; 943 fl6->flowi6_oif = p->link; 944 fl6->flowlabel = 0; 945 946 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 947 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 948 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 949 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 950 951 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 952 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 953 954 if (p->flags&IP6_TNL_F_CAP_XMIT && 955 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 956 dev->flags |= IFF_POINTOPOINT; 957 else 958 dev->flags &= ~IFF_POINTOPOINT; 959 960 /* Precalculate GRE options length */ 961 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 962 if (t->parms.o_flags&GRE_CSUM) 963 addend += 4; 964 if (t->parms.o_flags&GRE_KEY) 965 addend += 4; 966 if (t->parms.o_flags&GRE_SEQ) 967 addend += 4; 968 } 969 t->hlen = addend; 970 971 if (p->flags & IP6_TNL_F_CAP_XMIT) { 972 int strict = (ipv6_addr_type(&p->raddr) & 973 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 974 975 struct rt6_info *rt = rt6_lookup(t->net, 976 &p->raddr, &p->laddr, 977 p->link, strict); 978 979 if (!rt) 980 return; 981 982 if (rt->dst.dev) { 983 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 984 985 if (set_mtu) { 986 dev->mtu = rt->dst.dev->mtu - addend; 987 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 988 dev->mtu -= 8; 989 990 if (dev->mtu < IPV6_MIN_MTU) 991 dev->mtu = IPV6_MIN_MTU; 992 } 993 } 994 ip6_rt_put(rt); 995 } 996 } 997 998 static int ip6gre_tnl_change(struct ip6_tnl *t, 999 const struct __ip6_tnl_parm *p, int set_mtu) 1000 { 1001 t->parms.laddr = p->laddr; 1002 t->parms.raddr = p->raddr; 1003 t->parms.flags = p->flags; 1004 t->parms.hop_limit = p->hop_limit; 1005 t->parms.encap_limit = p->encap_limit; 1006 t->parms.flowinfo = p->flowinfo; 1007 t->parms.link = p->link; 1008 t->parms.proto = p->proto; 1009 t->parms.i_key = p->i_key; 1010 t->parms.o_key = p->o_key; 1011 t->parms.i_flags = p->i_flags; 1012 t->parms.o_flags = p->o_flags; 1013 ip6_tnl_dst_reset(t); 1014 ip6gre_tnl_link_config(t, set_mtu); 1015 return 0; 1016 } 1017 1018 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1019 const struct ip6_tnl_parm2 *u) 1020 { 1021 p->laddr = u->laddr; 1022 p->raddr = u->raddr; 1023 p->flags = u->flags; 1024 p->hop_limit = u->hop_limit; 1025 p->encap_limit = u->encap_limit; 1026 p->flowinfo = u->flowinfo; 1027 p->link = u->link; 1028 p->i_key = u->i_key; 1029 p->o_key = u->o_key; 1030 p->i_flags = u->i_flags; 1031 p->o_flags = u->o_flags; 1032 memcpy(p->name, u->name, sizeof(u->name)); 1033 } 1034 1035 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1036 const struct __ip6_tnl_parm *p) 1037 { 1038 u->proto = IPPROTO_GRE; 1039 u->laddr = p->laddr; 1040 u->raddr = p->raddr; 1041 u->flags = p->flags; 1042 u->hop_limit = p->hop_limit; 1043 u->encap_limit = p->encap_limit; 1044 u->flowinfo = p->flowinfo; 1045 u->link = p->link; 1046 u->i_key = p->i_key; 1047 u->o_key = p->o_key; 1048 u->i_flags = p->i_flags; 1049 u->o_flags = p->o_flags; 1050 memcpy(u->name, p->name, sizeof(u->name)); 1051 } 1052 1053 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1054 struct ifreq *ifr, int cmd) 1055 { 1056 int err = 0; 1057 struct ip6_tnl_parm2 p; 1058 struct __ip6_tnl_parm p1; 1059 struct ip6_tnl *t = netdev_priv(dev); 1060 struct net *net = t->net; 1061 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1062 1063 switch (cmd) { 1064 case SIOCGETTUNNEL: 1065 if (dev == ign->fb_tunnel_dev) { 1066 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1067 err = -EFAULT; 1068 break; 1069 } 1070 ip6gre_tnl_parm_from_user(&p1, &p); 1071 t = ip6gre_tunnel_locate(net, &p1, 0); 1072 if (!t) 1073 t = netdev_priv(dev); 1074 } 1075 memset(&p, 0, sizeof(p)); 1076 ip6gre_tnl_parm_to_user(&p, &t->parms); 1077 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1078 err = -EFAULT; 1079 break; 1080 1081 case SIOCADDTUNNEL: 1082 case SIOCCHGTUNNEL: 1083 err = -EPERM; 1084 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1085 goto done; 1086 1087 err = -EFAULT; 1088 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1089 goto done; 1090 1091 err = -EINVAL; 1092 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1093 goto done; 1094 1095 if (!(p.i_flags&GRE_KEY)) 1096 p.i_key = 0; 1097 if (!(p.o_flags&GRE_KEY)) 1098 p.o_key = 0; 1099 1100 ip6gre_tnl_parm_from_user(&p1, &p); 1101 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1102 1103 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1104 if (t) { 1105 if (t->dev != dev) { 1106 err = -EEXIST; 1107 break; 1108 } 1109 } else { 1110 t = netdev_priv(dev); 1111 1112 ip6gre_tunnel_unlink(ign, t); 1113 synchronize_net(); 1114 ip6gre_tnl_change(t, &p1, 1); 1115 ip6gre_tunnel_link(ign, t); 1116 netdev_state_change(dev); 1117 } 1118 } 1119 1120 if (t) { 1121 err = 0; 1122 1123 memset(&p, 0, sizeof(p)); 1124 ip6gre_tnl_parm_to_user(&p, &t->parms); 1125 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1126 err = -EFAULT; 1127 } else 1128 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1129 break; 1130 1131 case SIOCDELTUNNEL: 1132 err = -EPERM; 1133 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1134 goto done; 1135 1136 if (dev == ign->fb_tunnel_dev) { 1137 err = -EFAULT; 1138 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1139 goto done; 1140 err = -ENOENT; 1141 ip6gre_tnl_parm_from_user(&p1, &p); 1142 t = ip6gre_tunnel_locate(net, &p1, 0); 1143 if (!t) 1144 goto done; 1145 err = -EPERM; 1146 if (t == netdev_priv(ign->fb_tunnel_dev)) 1147 goto done; 1148 dev = t->dev; 1149 } 1150 unregister_netdevice(dev); 1151 err = 0; 1152 break; 1153 1154 default: 1155 err = -EINVAL; 1156 } 1157 1158 done: 1159 return err; 1160 } 1161 1162 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1163 { 1164 if (new_mtu < 68 || 1165 new_mtu > 0xFFF8 - dev->hard_header_len) 1166 return -EINVAL; 1167 dev->mtu = new_mtu; 1168 return 0; 1169 } 1170 1171 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1172 unsigned short type, 1173 const void *daddr, const void *saddr, unsigned int len) 1174 { 1175 struct ip6_tnl *t = netdev_priv(dev); 1176 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1177 __be16 *p = (__be16 *)(ipv6h+1); 1178 1179 ip6_flow_hdr(ipv6h, 0, 1180 ip6_make_flowlabel(dev_net(dev), skb, 1181 t->fl.u.ip6.flowlabel, true, 1182 &t->fl.u.ip6)); 1183 ipv6h->hop_limit = t->parms.hop_limit; 1184 ipv6h->nexthdr = NEXTHDR_GRE; 1185 ipv6h->saddr = t->parms.laddr; 1186 ipv6h->daddr = t->parms.raddr; 1187 1188 p[0] = t->parms.o_flags; 1189 p[1] = htons(type); 1190 1191 /* 1192 * Set the source hardware address. 1193 */ 1194 1195 if (saddr) 1196 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1197 if (daddr) 1198 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1199 if (!ipv6_addr_any(&ipv6h->daddr)) 1200 return t->hlen; 1201 1202 return -t->hlen; 1203 } 1204 1205 static const struct header_ops ip6gre_header_ops = { 1206 .create = ip6gre_header, 1207 }; 1208 1209 static const struct net_device_ops ip6gre_netdev_ops = { 1210 .ndo_init = ip6gre_tunnel_init, 1211 .ndo_uninit = ip6gre_tunnel_uninit, 1212 .ndo_start_xmit = ip6gre_tunnel_xmit, 1213 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1214 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1215 .ndo_get_stats64 = ip_tunnel_get_stats64, 1216 .ndo_get_iflink = ip6_tnl_get_iflink, 1217 }; 1218 1219 static void ip6gre_dev_free(struct net_device *dev) 1220 { 1221 struct ip6_tnl *t = netdev_priv(dev); 1222 1223 ip6_tnl_dst_destroy(t); 1224 free_percpu(dev->tstats); 1225 free_netdev(dev); 1226 } 1227 1228 static void ip6gre_tunnel_setup(struct net_device *dev) 1229 { 1230 struct ip6_tnl *t; 1231 1232 dev->netdev_ops = &ip6gre_netdev_ops; 1233 dev->destructor = ip6gre_dev_free; 1234 1235 dev->type = ARPHRD_IP6GRE; 1236 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1237 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1238 t = netdev_priv(dev); 1239 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1240 dev->mtu -= 8; 1241 dev->flags |= IFF_NOARP; 1242 dev->addr_len = sizeof(struct in6_addr); 1243 netif_keep_dst(dev); 1244 } 1245 1246 static int ip6gre_tunnel_init_common(struct net_device *dev) 1247 { 1248 struct ip6_tnl *tunnel; 1249 int ret; 1250 1251 tunnel = netdev_priv(dev); 1252 1253 tunnel->dev = dev; 1254 tunnel->net = dev_net(dev); 1255 strcpy(tunnel->parms.name, dev->name); 1256 1257 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1258 if (!dev->tstats) 1259 return -ENOMEM; 1260 1261 ret = ip6_tnl_dst_init(tunnel); 1262 if (ret) { 1263 free_percpu(dev->tstats); 1264 dev->tstats = NULL; 1265 return ret; 1266 } 1267 1268 return 0; 1269 } 1270 1271 static int ip6gre_tunnel_init(struct net_device *dev) 1272 { 1273 struct ip6_tnl *tunnel; 1274 int ret; 1275 1276 ret = ip6gre_tunnel_init_common(dev); 1277 if (ret) 1278 return ret; 1279 1280 tunnel = netdev_priv(dev); 1281 1282 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1283 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1284 1285 if (ipv6_addr_any(&tunnel->parms.raddr)) 1286 dev->header_ops = &ip6gre_header_ops; 1287 1288 return 0; 1289 } 1290 1291 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1292 { 1293 struct ip6_tnl *tunnel = netdev_priv(dev); 1294 1295 tunnel->dev = dev; 1296 tunnel->net = dev_net(dev); 1297 strcpy(tunnel->parms.name, dev->name); 1298 1299 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1300 1301 dev_hold(dev); 1302 } 1303 1304 1305 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1306 .handler = ip6gre_rcv, 1307 .err_handler = ip6gre_err, 1308 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1309 }; 1310 1311 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 1312 { 1313 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1314 struct net_device *dev, *aux; 1315 int prio; 1316 1317 for_each_netdev_safe(net, dev, aux) 1318 if (dev->rtnl_link_ops == &ip6gre_link_ops || 1319 dev->rtnl_link_ops == &ip6gre_tap_ops) 1320 unregister_netdevice_queue(dev, head); 1321 1322 for (prio = 0; prio < 4; prio++) { 1323 int h; 1324 for (h = 0; h < HASH_SIZE; h++) { 1325 struct ip6_tnl *t; 1326 1327 t = rtnl_dereference(ign->tunnels[prio][h]); 1328 1329 while (t) { 1330 /* If dev is in the same netns, it has already 1331 * been added to the list by the previous loop. 1332 */ 1333 if (!net_eq(dev_net(t->dev), net)) 1334 unregister_netdevice_queue(t->dev, 1335 head); 1336 t = rtnl_dereference(t->next); 1337 } 1338 } 1339 } 1340 } 1341 1342 static int __net_init ip6gre_init_net(struct net *net) 1343 { 1344 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1345 int err; 1346 1347 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1348 NET_NAME_UNKNOWN, 1349 ip6gre_tunnel_setup); 1350 if (!ign->fb_tunnel_dev) { 1351 err = -ENOMEM; 1352 goto err_alloc_dev; 1353 } 1354 dev_net_set(ign->fb_tunnel_dev, net); 1355 /* FB netdevice is special: we have one, and only one per netns. 1356 * Allowing to move it to another netns is clearly unsafe. 1357 */ 1358 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1359 1360 1361 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1362 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1363 1364 err = register_netdev(ign->fb_tunnel_dev); 1365 if (err) 1366 goto err_reg_dev; 1367 1368 rcu_assign_pointer(ign->tunnels_wc[0], 1369 netdev_priv(ign->fb_tunnel_dev)); 1370 return 0; 1371 1372 err_reg_dev: 1373 ip6gre_dev_free(ign->fb_tunnel_dev); 1374 err_alloc_dev: 1375 return err; 1376 } 1377 1378 static void __net_exit ip6gre_exit_net(struct net *net) 1379 { 1380 LIST_HEAD(list); 1381 1382 rtnl_lock(); 1383 ip6gre_destroy_tunnels(net, &list); 1384 unregister_netdevice_many(&list); 1385 rtnl_unlock(); 1386 } 1387 1388 static struct pernet_operations ip6gre_net_ops = { 1389 .init = ip6gre_init_net, 1390 .exit = ip6gre_exit_net, 1391 .id = &ip6gre_net_id, 1392 .size = sizeof(struct ip6gre_net), 1393 }; 1394 1395 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1396 { 1397 __be16 flags; 1398 1399 if (!data) 1400 return 0; 1401 1402 flags = 0; 1403 if (data[IFLA_GRE_IFLAGS]) 1404 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1405 if (data[IFLA_GRE_OFLAGS]) 1406 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1407 if (flags & (GRE_VERSION|GRE_ROUTING)) 1408 return -EINVAL; 1409 1410 return 0; 1411 } 1412 1413 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1414 { 1415 struct in6_addr daddr; 1416 1417 if (tb[IFLA_ADDRESS]) { 1418 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1419 return -EINVAL; 1420 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1421 return -EADDRNOTAVAIL; 1422 } 1423 1424 if (!data) 1425 goto out; 1426 1427 if (data[IFLA_GRE_REMOTE]) { 1428 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1429 if (ipv6_addr_any(&daddr)) 1430 return -EINVAL; 1431 } 1432 1433 out: 1434 return ip6gre_tunnel_validate(tb, data); 1435 } 1436 1437 1438 static void ip6gre_netlink_parms(struct nlattr *data[], 1439 struct __ip6_tnl_parm *parms) 1440 { 1441 memset(parms, 0, sizeof(*parms)); 1442 1443 if (!data) 1444 return; 1445 1446 if (data[IFLA_GRE_LINK]) 1447 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1448 1449 if (data[IFLA_GRE_IFLAGS]) 1450 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1451 1452 if (data[IFLA_GRE_OFLAGS]) 1453 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1454 1455 if (data[IFLA_GRE_IKEY]) 1456 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1457 1458 if (data[IFLA_GRE_OKEY]) 1459 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1460 1461 if (data[IFLA_GRE_LOCAL]) 1462 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]); 1463 1464 if (data[IFLA_GRE_REMOTE]) 1465 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1466 1467 if (data[IFLA_GRE_TTL]) 1468 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1469 1470 if (data[IFLA_GRE_ENCAP_LIMIT]) 1471 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1472 1473 if (data[IFLA_GRE_FLOWINFO]) 1474 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1475 1476 if (data[IFLA_GRE_FLAGS]) 1477 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1478 } 1479 1480 static int ip6gre_tap_init(struct net_device *dev) 1481 { 1482 struct ip6_tnl *tunnel; 1483 int ret; 1484 1485 ret = ip6gre_tunnel_init_common(dev); 1486 if (ret) 1487 return ret; 1488 1489 tunnel = netdev_priv(dev); 1490 1491 ip6gre_tnl_link_config(tunnel, 1); 1492 1493 return 0; 1494 } 1495 1496 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1497 .ndo_init = ip6gre_tap_init, 1498 .ndo_uninit = ip6gre_tunnel_uninit, 1499 .ndo_start_xmit = ip6gre_tunnel_xmit, 1500 .ndo_set_mac_address = eth_mac_addr, 1501 .ndo_validate_addr = eth_validate_addr, 1502 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1503 .ndo_get_stats64 = ip_tunnel_get_stats64, 1504 .ndo_get_iflink = ip6_tnl_get_iflink, 1505 }; 1506 1507 static void ip6gre_tap_setup(struct net_device *dev) 1508 { 1509 1510 ether_setup(dev); 1511 1512 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1513 dev->destructor = ip6gre_dev_free; 1514 1515 dev->features |= NETIF_F_NETNS_LOCAL; 1516 } 1517 1518 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1519 struct nlattr *tb[], struct nlattr *data[]) 1520 { 1521 struct ip6_tnl *nt; 1522 struct net *net = dev_net(dev); 1523 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1524 int err; 1525 1526 nt = netdev_priv(dev); 1527 ip6gre_netlink_parms(data, &nt->parms); 1528 1529 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1530 return -EEXIST; 1531 1532 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1533 eth_hw_addr_random(dev); 1534 1535 nt->dev = dev; 1536 nt->net = dev_net(dev); 1537 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1538 1539 /* Can use a lockless transmit, unless we generate output sequences */ 1540 if (!(nt->parms.o_flags & GRE_SEQ)) 1541 dev->features |= NETIF_F_LLTX; 1542 1543 err = register_netdevice(dev); 1544 if (err) 1545 goto out; 1546 1547 dev_hold(dev); 1548 ip6gre_tunnel_link(ign, nt); 1549 1550 out: 1551 return err; 1552 } 1553 1554 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1555 struct nlattr *data[]) 1556 { 1557 struct ip6_tnl *t, *nt = netdev_priv(dev); 1558 struct net *net = nt->net; 1559 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1560 struct __ip6_tnl_parm p; 1561 1562 if (dev == ign->fb_tunnel_dev) 1563 return -EINVAL; 1564 1565 ip6gre_netlink_parms(data, &p); 1566 1567 t = ip6gre_tunnel_locate(net, &p, 0); 1568 1569 if (t) { 1570 if (t->dev != dev) 1571 return -EEXIST; 1572 } else { 1573 t = nt; 1574 1575 ip6gre_tunnel_unlink(ign, t); 1576 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1577 ip6gre_tunnel_link(ign, t); 1578 netdev_state_change(dev); 1579 } 1580 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