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 IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) 65 #define IPV6_TCLASS_SHIFT 20 66 67 #define HASH_SIZE_SHIFT 5 68 #define HASH_SIZE (1 << HASH_SIZE_SHIFT) 69 70 static int ip6gre_net_id __read_mostly; 71 struct ip6gre_net { 72 struct ip6_tnl __rcu *tunnels[4][HASH_SIZE]; 73 74 struct net_device *fb_tunnel_dev; 75 }; 76 77 static struct rtnl_link_ops ip6gre_link_ops __read_mostly; 78 static int ip6gre_tunnel_init(struct net_device *dev); 79 static void ip6gre_tunnel_setup(struct net_device *dev); 80 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t); 81 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu); 82 83 /* Tunnel hash table */ 84 85 /* 86 4 hash tables: 87 88 3: (remote,local) 89 2: (remote,*) 90 1: (*,local) 91 0: (*,*) 92 93 We require exact key match i.e. if a key is present in packet 94 it will match only tunnel with the same key; if it is not present, 95 it will match only keyless tunnel. 96 97 All keysless packets, if not matched configured keyless tunnels 98 will match fallback tunnel. 99 */ 100 101 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 1)) 102 static u32 HASH_ADDR(const struct in6_addr *addr) 103 { 104 u32 hash = ipv6_addr_hash(addr); 105 106 return hash_32(hash, HASH_SIZE_SHIFT); 107 } 108 109 #define tunnels_r_l tunnels[3] 110 #define tunnels_r tunnels[2] 111 #define tunnels_l tunnels[1] 112 #define tunnels_wc tunnels[0] 113 114 /* Given src, dst and key, find appropriate for input tunnel. */ 115 116 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev, 117 const struct in6_addr *remote, const struct in6_addr *local, 118 __be32 key, __be16 gre_proto) 119 { 120 struct net *net = dev_net(dev); 121 int link = dev->ifindex; 122 unsigned int h0 = HASH_ADDR(remote); 123 unsigned int h1 = HASH_KEY(key); 124 struct ip6_tnl *t, *cand = NULL; 125 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 126 int dev_type = (gre_proto == htons(ETH_P_TEB)) ? 127 ARPHRD_ETHER : ARPHRD_IP6GRE; 128 int score, cand_score = 4; 129 130 for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) { 131 if (!ipv6_addr_equal(local, &t->parms.laddr) || 132 !ipv6_addr_equal(remote, &t->parms.raddr) || 133 key != t->parms.i_key || 134 !(t->dev->flags & IFF_UP)) 135 continue; 136 137 if (t->dev->type != ARPHRD_IP6GRE && 138 t->dev->type != dev_type) 139 continue; 140 141 score = 0; 142 if (t->parms.link != link) 143 score |= 1; 144 if (t->dev->type != dev_type) 145 score |= 2; 146 if (score == 0) 147 return t; 148 149 if (score < cand_score) { 150 cand = t; 151 cand_score = score; 152 } 153 } 154 155 for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) { 156 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 157 key != t->parms.i_key || 158 !(t->dev->flags & IFF_UP)) 159 continue; 160 161 if (t->dev->type != ARPHRD_IP6GRE && 162 t->dev->type != dev_type) 163 continue; 164 165 score = 0; 166 if (t->parms.link != link) 167 score |= 1; 168 if (t->dev->type != dev_type) 169 score |= 2; 170 if (score == 0) 171 return t; 172 173 if (score < cand_score) { 174 cand = t; 175 cand_score = score; 176 } 177 } 178 179 for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) { 180 if ((!ipv6_addr_equal(local, &t->parms.laddr) && 181 (!ipv6_addr_equal(local, &t->parms.raddr) || 182 !ipv6_addr_is_multicast(local))) || 183 key != t->parms.i_key || 184 !(t->dev->flags & IFF_UP)) 185 continue; 186 187 if (t->dev->type != ARPHRD_IP6GRE && 188 t->dev->type != dev_type) 189 continue; 190 191 score = 0; 192 if (t->parms.link != link) 193 score |= 1; 194 if (t->dev->type != dev_type) 195 score |= 2; 196 if (score == 0) 197 return t; 198 199 if (score < cand_score) { 200 cand = t; 201 cand_score = score; 202 } 203 } 204 205 for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) { 206 if (t->parms.i_key != key || 207 !(t->dev->flags & IFF_UP)) 208 continue; 209 210 if (t->dev->type != ARPHRD_IP6GRE && 211 t->dev->type != dev_type) 212 continue; 213 214 score = 0; 215 if (t->parms.link != link) 216 score |= 1; 217 if (t->dev->type != dev_type) 218 score |= 2; 219 if (score == 0) 220 return t; 221 222 if (score < cand_score) { 223 cand = t; 224 cand_score = score; 225 } 226 } 227 228 if (cand != NULL) 229 return cand; 230 231 dev = ign->fb_tunnel_dev; 232 if (dev->flags & IFF_UP) 233 return netdev_priv(dev); 234 235 return NULL; 236 } 237 238 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign, 239 const struct __ip6_tnl_parm *p) 240 { 241 const struct in6_addr *remote = &p->raddr; 242 const struct in6_addr *local = &p->laddr; 243 unsigned int h = HASH_KEY(p->i_key); 244 int prio = 0; 245 246 if (!ipv6_addr_any(local)) 247 prio |= 1; 248 if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) { 249 prio |= 2; 250 h ^= HASH_ADDR(remote); 251 } 252 253 return &ign->tunnels[prio][h]; 254 } 255 256 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign, 257 const struct ip6_tnl *t) 258 { 259 return __ip6gre_bucket(ign, &t->parms); 260 } 261 262 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t) 263 { 264 struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t); 265 266 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 267 rcu_assign_pointer(*tp, t); 268 } 269 270 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t) 271 { 272 struct ip6_tnl __rcu **tp; 273 struct ip6_tnl *iter; 274 275 for (tp = ip6gre_bucket(ign, t); 276 (iter = rtnl_dereference(*tp)) != NULL; 277 tp = &iter->next) { 278 if (t == iter) { 279 rcu_assign_pointer(*tp, t->next); 280 break; 281 } 282 } 283 } 284 285 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net, 286 const struct __ip6_tnl_parm *parms, 287 int type) 288 { 289 const struct in6_addr *remote = &parms->raddr; 290 const struct in6_addr *local = &parms->laddr; 291 __be32 key = parms->i_key; 292 int link = parms->link; 293 struct ip6_tnl *t; 294 struct ip6_tnl __rcu **tp; 295 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 296 297 for (tp = __ip6gre_bucket(ign, parms); 298 (t = rtnl_dereference(*tp)) != NULL; 299 tp = &t->next) 300 if (ipv6_addr_equal(local, &t->parms.laddr) && 301 ipv6_addr_equal(remote, &t->parms.raddr) && 302 key == t->parms.i_key && 303 link == t->parms.link && 304 type == t->dev->type) 305 break; 306 307 return t; 308 } 309 310 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, 311 const struct __ip6_tnl_parm *parms, int create) 312 { 313 struct ip6_tnl *t, *nt; 314 struct net_device *dev; 315 char name[IFNAMSIZ]; 316 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 317 318 t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE); 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, 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 net *net = dev_net(dev); 360 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 361 362 ip6gre_tunnel_unlink(ign, netdev_priv(dev)); 363 dev_put(dev); 364 } 365 366 367 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 368 u8 type, u8 code, int offset, __be32 info) 369 { 370 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 371 __be16 *p = (__be16 *)(skb->data + offset); 372 int grehlen = offset + 4; 373 struct ip6_tnl *t; 374 __be16 flags; 375 376 flags = p[0]; 377 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 378 if (flags&(GRE_VERSION|GRE_ROUTING)) 379 return; 380 if (flags&GRE_KEY) { 381 grehlen += 4; 382 if (flags&GRE_CSUM) 383 grehlen += 4; 384 } 385 } 386 387 /* If only 8 bytes returned, keyed message will be dropped here */ 388 if (!pskb_may_pull(skb, grehlen)) 389 return; 390 ipv6h = (const struct ipv6hdr *)skb->data; 391 p = (__be16 *)(skb->data + offset); 392 393 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 394 flags & GRE_KEY ? 395 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 396 p[1]); 397 if (t == NULL) 398 return; 399 400 switch (type) { 401 __u32 teli; 402 struct ipv6_tlv_tnl_enc_lim *tel; 403 __u32 mtu; 404 case ICMPV6_DEST_UNREACH: 405 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n", 406 t->parms.name); 407 break; 408 case ICMPV6_TIME_EXCEED: 409 if (code == ICMPV6_EXC_HOPLIMIT) { 410 net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 411 t->parms.name); 412 } 413 break; 414 case ICMPV6_PARAMPROB: 415 teli = 0; 416 if (code == ICMPV6_HDR_FIELD) 417 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 418 419 if (teli && teli == info - 2) { 420 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 421 if (tel->encap_limit == 0) { 422 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 423 t->parms.name); 424 } 425 } else { 426 net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 427 t->parms.name); 428 } 429 break; 430 case ICMPV6_PKT_TOOBIG: 431 mtu = info - offset; 432 if (mtu < IPV6_MIN_MTU) 433 mtu = IPV6_MIN_MTU; 434 t->dev->mtu = mtu; 435 break; 436 } 437 438 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 439 t->err_count++; 440 else 441 t->err_count = 1; 442 t->err_time = jiffies; 443 } 444 445 static int ip6gre_rcv(struct sk_buff *skb) 446 { 447 const struct ipv6hdr *ipv6h; 448 u8 *h; 449 __be16 flags; 450 __sum16 csum = 0; 451 __be32 key = 0; 452 u32 seqno = 0; 453 struct ip6_tnl *tunnel; 454 int offset = 4; 455 __be16 gre_proto; 456 int err; 457 458 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 459 goto drop; 460 461 ipv6h = ipv6_hdr(skb); 462 h = skb->data; 463 flags = *(__be16 *)h; 464 465 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 466 /* - Version must be 0. 467 - We do not support routing headers. 468 */ 469 if (flags&(GRE_VERSION|GRE_ROUTING)) 470 goto drop; 471 472 if (flags&GRE_CSUM) { 473 switch (skb->ip_summed) { 474 case CHECKSUM_COMPLETE: 475 csum = csum_fold(skb->csum); 476 if (!csum) 477 break; 478 /* fall through */ 479 case CHECKSUM_NONE: 480 skb->csum = 0; 481 csum = __skb_checksum_complete(skb); 482 skb->ip_summed = CHECKSUM_COMPLETE; 483 } 484 offset += 4; 485 } 486 if (flags&GRE_KEY) { 487 key = *(__be32 *)(h + offset); 488 offset += 4; 489 } 490 if (flags&GRE_SEQ) { 491 seqno = ntohl(*(__be32 *)(h + offset)); 492 offset += 4; 493 } 494 } 495 496 gre_proto = *(__be16 *)(h + 2); 497 498 tunnel = ip6gre_tunnel_lookup(skb->dev, 499 &ipv6h->saddr, &ipv6h->daddr, key, 500 gre_proto); 501 if (tunnel) { 502 struct pcpu_tstats *tstats; 503 504 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 505 goto drop; 506 507 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 508 tunnel->dev->stats.rx_dropped++; 509 goto drop; 510 } 511 512 skb->protocol = gre_proto; 513 /* WCCP version 1 and 2 protocol decoding. 514 * - Change protocol to IP 515 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 516 */ 517 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 518 skb->protocol = htons(ETH_P_IP); 519 if ((*(h + offset) & 0xF0) != 0x40) 520 offset += 4; 521 } 522 523 skb->mac_header = skb->network_header; 524 __pskb_pull(skb, offset); 525 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 526 527 if (((flags&GRE_CSUM) && csum) || 528 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 529 tunnel->dev->stats.rx_crc_errors++; 530 tunnel->dev->stats.rx_errors++; 531 goto drop; 532 } 533 if (tunnel->parms.i_flags&GRE_SEQ) { 534 if (!(flags&GRE_SEQ) || 535 (tunnel->i_seqno && 536 (s32)(seqno - tunnel->i_seqno) < 0)) { 537 tunnel->dev->stats.rx_fifo_errors++; 538 tunnel->dev->stats.rx_errors++; 539 goto drop; 540 } 541 tunnel->i_seqno = seqno + 1; 542 } 543 544 /* Warning: All skb pointers will be invalidated! */ 545 if (tunnel->dev->type == ARPHRD_ETHER) { 546 if (!pskb_may_pull(skb, ETH_HLEN)) { 547 tunnel->dev->stats.rx_length_errors++; 548 tunnel->dev->stats.rx_errors++; 549 goto drop; 550 } 551 552 ipv6h = ipv6_hdr(skb); 553 skb->protocol = eth_type_trans(skb, tunnel->dev); 554 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 555 } 556 557 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 558 559 skb_reset_network_header(skb); 560 561 err = IP6_ECN_decapsulate(ipv6h, skb); 562 if (unlikely(err)) { 563 if (log_ecn_error) 564 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 565 &ipv6h->saddr, 566 ipv6_get_dsfield(ipv6h)); 567 if (err > 1) { 568 ++tunnel->dev->stats.rx_frame_errors; 569 ++tunnel->dev->stats.rx_errors; 570 goto drop; 571 } 572 } 573 574 tstats = this_cpu_ptr(tunnel->dev->tstats); 575 u64_stats_update_begin(&tstats->syncp); 576 tstats->rx_packets++; 577 tstats->rx_bytes += skb->len; 578 u64_stats_update_end(&tstats->syncp); 579 580 netif_rx(skb); 581 582 return 0; 583 } 584 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 585 586 drop: 587 kfree_skb(skb); 588 return 0; 589 } 590 591 struct ipv6_tel_txoption { 592 struct ipv6_txoptions ops; 593 __u8 dst_opt[8]; 594 }; 595 596 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 597 { 598 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 599 600 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 601 opt->dst_opt[3] = 1; 602 opt->dst_opt[4] = encap_limit; 603 opt->dst_opt[5] = IPV6_TLV_PADN; 604 opt->dst_opt[6] = 1; 605 606 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 607 opt->ops.opt_nflen = 8; 608 } 609 610 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 611 struct net_device *dev, 612 __u8 dsfield, 613 struct flowi6 *fl6, 614 int encap_limit, 615 __u32 *pmtu) 616 { 617 struct net *net = dev_net(dev); 618 struct ip6_tnl *tunnel = netdev_priv(dev); 619 struct net_device *tdev; /* Device to other host */ 620 struct ipv6hdr *ipv6h; /* Our new IP header */ 621 unsigned int max_headroom; /* The extra header space needed */ 622 int gre_hlen; 623 struct ipv6_tel_txoption opt; 624 int mtu; 625 struct dst_entry *dst = NULL, *ndst = NULL; 626 struct net_device_stats *stats = &tunnel->dev->stats; 627 int err = -1; 628 u8 proto; 629 struct sk_buff *new_skb; 630 631 if (dev->type == ARPHRD_ETHER) 632 IPCB(skb)->flags = 0; 633 634 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 635 gre_hlen = 0; 636 ipv6h = (struct ipv6hdr *)skb->data; 637 fl6->daddr = ipv6h->daddr; 638 } else { 639 gre_hlen = tunnel->hlen; 640 fl6->daddr = tunnel->parms.raddr; 641 } 642 643 if (!fl6->flowi6_mark) 644 dst = ip6_tnl_dst_check(tunnel); 645 646 if (!dst) { 647 ndst = ip6_route_output(net, NULL, fl6); 648 649 if (ndst->error) 650 goto tx_err_link_failure; 651 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); 652 if (IS_ERR(ndst)) { 653 err = PTR_ERR(ndst); 654 ndst = NULL; 655 goto tx_err_link_failure; 656 } 657 dst = ndst; 658 } 659 660 tdev = dst->dev; 661 662 if (tdev == dev) { 663 stats->collisions++; 664 net_warn_ratelimited("%s: Local routing loop detected!\n", 665 tunnel->parms.name); 666 goto tx_err_dst_release; 667 } 668 669 mtu = dst_mtu(dst) - sizeof(*ipv6h); 670 if (encap_limit >= 0) { 671 max_headroom += 8; 672 mtu -= 8; 673 } 674 if (mtu < IPV6_MIN_MTU) 675 mtu = IPV6_MIN_MTU; 676 if (skb_dst(skb)) 677 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 678 if (skb->len > mtu) { 679 *pmtu = mtu; 680 err = -EMSGSIZE; 681 goto tx_err_dst_release; 682 } 683 684 if (tunnel->err_count > 0) { 685 if (time_before(jiffies, 686 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 687 tunnel->err_count--; 688 689 dst_link_failure(skb); 690 } else 691 tunnel->err_count = 0; 692 } 693 694 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); 695 696 max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; 697 698 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 699 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 700 new_skb = skb_realloc_headroom(skb, max_headroom); 701 if (max_headroom > dev->needed_headroom) 702 dev->needed_headroom = max_headroom; 703 if (!new_skb) 704 goto tx_err_dst_release; 705 706 if (skb->sk) 707 skb_set_owner_w(new_skb, skb->sk); 708 consume_skb(skb); 709 skb = new_skb; 710 } 711 712 if (fl6->flowi6_mark) { 713 skb_dst_set(skb, dst); 714 ndst = NULL; 715 } else { 716 skb_dst_set_noref(skb, dst); 717 } 718 719 proto = NEXTHDR_GRE; 720 if (encap_limit >= 0) { 721 init_tel_txopt(&opt, encap_limit); 722 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 723 } 724 725 if (likely(!skb->encapsulation)) { 726 skb_reset_inner_headers(skb); 727 skb->encapsulation = 1; 728 } 729 730 skb_push(skb, gre_hlen); 731 skb_reset_network_header(skb); 732 skb_set_transport_header(skb, sizeof(*ipv6h)); 733 734 /* 735 * Push down and install the IP header. 736 */ 737 ipv6h = ipv6_hdr(skb); 738 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel); 739 ipv6h->hop_limit = tunnel->parms.hop_limit; 740 ipv6h->nexthdr = proto; 741 ipv6h->saddr = fl6->saddr; 742 ipv6h->daddr = fl6->daddr; 743 744 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 745 ((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ? 746 htons(ETH_P_TEB) : skb->protocol; 747 748 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 749 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 750 751 if (tunnel->parms.o_flags&GRE_SEQ) { 752 ++tunnel->o_seqno; 753 *ptr = htonl(tunnel->o_seqno); 754 ptr--; 755 } 756 if (tunnel->parms.o_flags&GRE_KEY) { 757 *ptr = tunnel->parms.o_key; 758 ptr--; 759 } 760 if (tunnel->parms.o_flags&GRE_CSUM) { 761 *ptr = 0; 762 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 763 skb->len - sizeof(struct ipv6hdr)); 764 } 765 } 766 767 ip6tunnel_xmit(skb, dev); 768 if (ndst) 769 ip6_tnl_dst_store(tunnel, ndst); 770 return 0; 771 tx_err_link_failure: 772 stats->tx_carrier_errors++; 773 dst_link_failure(skb); 774 tx_err_dst_release: 775 dst_release(ndst); 776 return err; 777 } 778 779 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 780 { 781 struct ip6_tnl *t = netdev_priv(dev); 782 const struct iphdr *iph = ip_hdr(skb); 783 int encap_limit = -1; 784 struct flowi6 fl6; 785 __u8 dsfield; 786 __u32 mtu; 787 int err; 788 789 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 790 encap_limit = t->parms.encap_limit; 791 792 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 793 fl6.flowi6_proto = IPPROTO_IPIP; 794 795 dsfield = ipv4_get_dsfield(iph); 796 797 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 798 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 799 & IPV6_TCLASS_MASK; 800 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 801 fl6.flowi6_mark = skb->mark; 802 803 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 804 if (err != 0) { 805 /* XXX: send ICMP error even if DF is not set. */ 806 if (err == -EMSGSIZE) 807 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 808 htonl(mtu)); 809 return -1; 810 } 811 812 return 0; 813 } 814 815 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 816 { 817 struct ip6_tnl *t = netdev_priv(dev); 818 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 819 int encap_limit = -1; 820 __u16 offset; 821 struct flowi6 fl6; 822 __u8 dsfield; 823 __u32 mtu; 824 int err; 825 826 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 827 return -1; 828 829 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 830 if (offset > 0) { 831 struct ipv6_tlv_tnl_enc_lim *tel; 832 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 833 if (tel->encap_limit == 0) { 834 icmpv6_send(skb, ICMPV6_PARAMPROB, 835 ICMPV6_HDR_FIELD, offset + 2); 836 return -1; 837 } 838 encap_limit = tel->encap_limit - 1; 839 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 840 encap_limit = t->parms.encap_limit; 841 842 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 843 fl6.flowi6_proto = IPPROTO_IPV6; 844 845 dsfield = ipv6_get_dsfield(ipv6h); 846 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 847 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 848 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 849 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 850 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 851 fl6.flowi6_mark = skb->mark; 852 853 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 854 if (err != 0) { 855 if (err == -EMSGSIZE) 856 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 857 return -1; 858 } 859 860 return 0; 861 } 862 863 /** 864 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 865 * @t: the outgoing tunnel device 866 * @hdr: IPv6 header from the incoming packet 867 * 868 * Description: 869 * Avoid trivial tunneling loop by checking that tunnel exit-point 870 * doesn't match source of incoming packet. 871 * 872 * Return: 873 * 1 if conflict, 874 * 0 else 875 **/ 876 877 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 878 const struct ipv6hdr *hdr) 879 { 880 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 881 } 882 883 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 884 { 885 struct ip6_tnl *t = netdev_priv(dev); 886 int encap_limit = -1; 887 struct flowi6 fl6; 888 __u32 mtu; 889 int err; 890 891 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 892 encap_limit = t->parms.encap_limit; 893 894 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 895 fl6.flowi6_proto = skb->protocol; 896 897 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 898 899 return err; 900 } 901 902 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 903 struct net_device *dev) 904 { 905 struct ip6_tnl *t = netdev_priv(dev); 906 struct net_device_stats *stats = &t->dev->stats; 907 int ret; 908 909 if (!ip6_tnl_xmit_ctl(t)) 910 goto tx_err; 911 912 switch (skb->protocol) { 913 case htons(ETH_P_IP): 914 ret = ip6gre_xmit_ipv4(skb, dev); 915 break; 916 case htons(ETH_P_IPV6): 917 ret = ip6gre_xmit_ipv6(skb, dev); 918 break; 919 default: 920 ret = ip6gre_xmit_other(skb, dev); 921 break; 922 } 923 924 if (ret < 0) 925 goto tx_err; 926 927 return NETDEV_TX_OK; 928 929 tx_err: 930 stats->tx_errors++; 931 stats->tx_dropped++; 932 kfree_skb(skb); 933 return NETDEV_TX_OK; 934 } 935 936 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 937 { 938 struct net_device *dev = t->dev; 939 struct __ip6_tnl_parm *p = &t->parms; 940 struct flowi6 *fl6 = &t->fl.u.ip6; 941 int addend = sizeof(struct ipv6hdr) + 4; 942 943 if (dev->type != ARPHRD_ETHER) { 944 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 945 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 946 } 947 948 /* Set up flowi template */ 949 fl6->saddr = p->laddr; 950 fl6->daddr = p->raddr; 951 fl6->flowi6_oif = p->link; 952 fl6->flowlabel = 0; 953 954 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 955 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 956 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 957 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 958 959 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 960 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 961 962 if (p->flags&IP6_TNL_F_CAP_XMIT && 963 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 964 dev->flags |= IFF_POINTOPOINT; 965 else 966 dev->flags &= ~IFF_POINTOPOINT; 967 968 dev->iflink = p->link; 969 970 /* Precalculate GRE options length */ 971 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 972 if (t->parms.o_flags&GRE_CSUM) 973 addend += 4; 974 if (t->parms.o_flags&GRE_KEY) 975 addend += 4; 976 if (t->parms.o_flags&GRE_SEQ) 977 addend += 4; 978 } 979 980 if (p->flags & IP6_TNL_F_CAP_XMIT) { 981 int strict = (ipv6_addr_type(&p->raddr) & 982 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 983 984 struct rt6_info *rt = rt6_lookup(dev_net(dev), 985 &p->raddr, &p->laddr, 986 p->link, strict); 987 988 if (rt == NULL) 989 return; 990 991 if (rt->dst.dev) { 992 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 993 994 if (set_mtu) { 995 dev->mtu = rt->dst.dev->mtu - addend; 996 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 997 dev->mtu -= 8; 998 999 if (dev->mtu < IPV6_MIN_MTU) 1000 dev->mtu = IPV6_MIN_MTU; 1001 } 1002 } 1003 ip6_rt_put(rt); 1004 } 1005 1006 t->hlen = addend; 1007 } 1008 1009 static int ip6gre_tnl_change(struct ip6_tnl *t, 1010 const struct __ip6_tnl_parm *p, int set_mtu) 1011 { 1012 t->parms.laddr = p->laddr; 1013 t->parms.raddr = p->raddr; 1014 t->parms.flags = p->flags; 1015 t->parms.hop_limit = p->hop_limit; 1016 t->parms.encap_limit = p->encap_limit; 1017 t->parms.flowinfo = p->flowinfo; 1018 t->parms.link = p->link; 1019 t->parms.proto = p->proto; 1020 t->parms.i_key = p->i_key; 1021 t->parms.o_key = p->o_key; 1022 t->parms.i_flags = p->i_flags; 1023 t->parms.o_flags = p->o_flags; 1024 ip6_tnl_dst_reset(t); 1025 ip6gre_tnl_link_config(t, set_mtu); 1026 return 0; 1027 } 1028 1029 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1030 const struct ip6_tnl_parm2 *u) 1031 { 1032 p->laddr = u->laddr; 1033 p->raddr = u->raddr; 1034 p->flags = u->flags; 1035 p->hop_limit = u->hop_limit; 1036 p->encap_limit = u->encap_limit; 1037 p->flowinfo = u->flowinfo; 1038 p->link = u->link; 1039 p->i_key = u->i_key; 1040 p->o_key = u->o_key; 1041 p->i_flags = u->i_flags; 1042 p->o_flags = u->o_flags; 1043 memcpy(p->name, u->name, sizeof(u->name)); 1044 } 1045 1046 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1047 const struct __ip6_tnl_parm *p) 1048 { 1049 u->proto = IPPROTO_GRE; 1050 u->laddr = p->laddr; 1051 u->raddr = p->raddr; 1052 u->flags = p->flags; 1053 u->hop_limit = p->hop_limit; 1054 u->encap_limit = p->encap_limit; 1055 u->flowinfo = p->flowinfo; 1056 u->link = p->link; 1057 u->i_key = p->i_key; 1058 u->o_key = p->o_key; 1059 u->i_flags = p->i_flags; 1060 u->o_flags = p->o_flags; 1061 memcpy(u->name, p->name, sizeof(u->name)); 1062 } 1063 1064 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1065 struct ifreq *ifr, int cmd) 1066 { 1067 int err = 0; 1068 struct ip6_tnl_parm2 p; 1069 struct __ip6_tnl_parm p1; 1070 struct ip6_tnl *t; 1071 struct net *net = dev_net(dev); 1072 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1073 1074 switch (cmd) { 1075 case SIOCGETTUNNEL: 1076 t = NULL; 1077 if (dev == ign->fb_tunnel_dev) { 1078 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1079 err = -EFAULT; 1080 break; 1081 } 1082 ip6gre_tnl_parm_from_user(&p1, &p); 1083 t = ip6gre_tunnel_locate(net, &p1, 0); 1084 } 1085 if (t == NULL) 1086 t = netdev_priv(dev); 1087 memset(&p, 0, sizeof(p)); 1088 ip6gre_tnl_parm_to_user(&p, &t->parms); 1089 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1090 err = -EFAULT; 1091 break; 1092 1093 case SIOCADDTUNNEL: 1094 case SIOCCHGTUNNEL: 1095 err = -EPERM; 1096 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1097 goto done; 1098 1099 err = -EFAULT; 1100 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1101 goto done; 1102 1103 err = -EINVAL; 1104 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1105 goto done; 1106 1107 if (!(p.i_flags&GRE_KEY)) 1108 p.i_key = 0; 1109 if (!(p.o_flags&GRE_KEY)) 1110 p.o_key = 0; 1111 1112 ip6gre_tnl_parm_from_user(&p1, &p); 1113 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1114 1115 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1116 if (t != NULL) { 1117 if (t->dev != dev) { 1118 err = -EEXIST; 1119 break; 1120 } 1121 } else { 1122 t = netdev_priv(dev); 1123 1124 ip6gre_tunnel_unlink(ign, t); 1125 synchronize_net(); 1126 ip6gre_tnl_change(t, &p1, 1); 1127 ip6gre_tunnel_link(ign, t); 1128 netdev_state_change(dev); 1129 } 1130 } 1131 1132 if (t) { 1133 err = 0; 1134 1135 memset(&p, 0, sizeof(p)); 1136 ip6gre_tnl_parm_to_user(&p, &t->parms); 1137 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1138 err = -EFAULT; 1139 } else 1140 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1141 break; 1142 1143 case SIOCDELTUNNEL: 1144 err = -EPERM; 1145 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1146 goto done; 1147 1148 if (dev == ign->fb_tunnel_dev) { 1149 err = -EFAULT; 1150 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1151 goto done; 1152 err = -ENOENT; 1153 ip6gre_tnl_parm_from_user(&p1, &p); 1154 t = ip6gre_tunnel_locate(net, &p1, 0); 1155 if (t == NULL) 1156 goto done; 1157 err = -EPERM; 1158 if (t == netdev_priv(ign->fb_tunnel_dev)) 1159 goto done; 1160 dev = t->dev; 1161 } 1162 unregister_netdevice(dev); 1163 err = 0; 1164 break; 1165 1166 default: 1167 err = -EINVAL; 1168 } 1169 1170 done: 1171 return err; 1172 } 1173 1174 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1175 { 1176 struct ip6_tnl *tunnel = netdev_priv(dev); 1177 if (new_mtu < 68 || 1178 new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen) 1179 return -EINVAL; 1180 dev->mtu = new_mtu; 1181 return 0; 1182 } 1183 1184 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1185 unsigned short type, 1186 const void *daddr, const void *saddr, unsigned int len) 1187 { 1188 struct ip6_tnl *t = netdev_priv(dev); 1189 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1190 __be16 *p = (__be16 *)(ipv6h+1); 1191 1192 ip6_flow_hdr(ipv6h, 0, t->fl.u.ip6.flowlabel); 1193 ipv6h->hop_limit = t->parms.hop_limit; 1194 ipv6h->nexthdr = NEXTHDR_GRE; 1195 ipv6h->saddr = t->parms.laddr; 1196 ipv6h->daddr = t->parms.raddr; 1197 1198 p[0] = t->parms.o_flags; 1199 p[1] = htons(type); 1200 1201 /* 1202 * Set the source hardware address. 1203 */ 1204 1205 if (saddr) 1206 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1207 if (daddr) 1208 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1209 if (!ipv6_addr_any(&ipv6h->daddr)) 1210 return t->hlen; 1211 1212 return -t->hlen; 1213 } 1214 1215 static const struct header_ops ip6gre_header_ops = { 1216 .create = ip6gre_header, 1217 }; 1218 1219 static const struct net_device_ops ip6gre_netdev_ops = { 1220 .ndo_init = ip6gre_tunnel_init, 1221 .ndo_uninit = ip6gre_tunnel_uninit, 1222 .ndo_start_xmit = ip6gre_tunnel_xmit, 1223 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1224 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1225 .ndo_get_stats64 = ip_tunnel_get_stats64, 1226 }; 1227 1228 static void ip6gre_dev_free(struct net_device *dev) 1229 { 1230 free_percpu(dev->tstats); 1231 free_netdev(dev); 1232 } 1233 1234 static void ip6gre_tunnel_setup(struct net_device *dev) 1235 { 1236 struct ip6_tnl *t; 1237 1238 dev->netdev_ops = &ip6gre_netdev_ops; 1239 dev->destructor = ip6gre_dev_free; 1240 1241 dev->type = ARPHRD_IP6GRE; 1242 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1243 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1244 t = netdev_priv(dev); 1245 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1246 dev->mtu -= 8; 1247 dev->flags |= IFF_NOARP; 1248 dev->iflink = 0; 1249 dev->addr_len = sizeof(struct in6_addr); 1250 dev->features |= NETIF_F_NETNS_LOCAL; 1251 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1252 } 1253 1254 static int ip6gre_tunnel_init(struct net_device *dev) 1255 { 1256 struct ip6_tnl *tunnel; 1257 1258 tunnel = netdev_priv(dev); 1259 1260 tunnel->dev = dev; 1261 tunnel->net = dev_net(dev); 1262 strcpy(tunnel->parms.name, dev->name); 1263 1264 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1265 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1266 1267 if (ipv6_addr_any(&tunnel->parms.raddr)) 1268 dev->header_ops = &ip6gre_header_ops; 1269 1270 dev->tstats = alloc_percpu(struct pcpu_tstats); 1271 if (!dev->tstats) 1272 return -ENOMEM; 1273 1274 return 0; 1275 } 1276 1277 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1278 { 1279 struct ip6_tnl *tunnel = netdev_priv(dev); 1280 1281 tunnel->dev = dev; 1282 tunnel->net = dev_net(dev); 1283 strcpy(tunnel->parms.name, dev->name); 1284 1285 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1286 1287 dev_hold(dev); 1288 } 1289 1290 1291 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1292 .handler = ip6gre_rcv, 1293 .err_handler = ip6gre_err, 1294 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1295 }; 1296 1297 static void ip6gre_destroy_tunnels(struct ip6gre_net *ign, 1298 struct list_head *head) 1299 { 1300 int prio; 1301 1302 for (prio = 0; prio < 4; prio++) { 1303 int h; 1304 for (h = 0; h < HASH_SIZE; h++) { 1305 struct ip6_tnl *t; 1306 1307 t = rtnl_dereference(ign->tunnels[prio][h]); 1308 1309 while (t != NULL) { 1310 unregister_netdevice_queue(t->dev, head); 1311 t = rtnl_dereference(t->next); 1312 } 1313 } 1314 } 1315 } 1316 1317 static int __net_init ip6gre_init_net(struct net *net) 1318 { 1319 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1320 int err; 1321 1322 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1323 ip6gre_tunnel_setup); 1324 if (!ign->fb_tunnel_dev) { 1325 err = -ENOMEM; 1326 goto err_alloc_dev; 1327 } 1328 dev_net_set(ign->fb_tunnel_dev, net); 1329 1330 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1331 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1332 1333 err = register_netdev(ign->fb_tunnel_dev); 1334 if (err) 1335 goto err_reg_dev; 1336 1337 rcu_assign_pointer(ign->tunnels_wc[0], 1338 netdev_priv(ign->fb_tunnel_dev)); 1339 return 0; 1340 1341 err_reg_dev: 1342 ip6gre_dev_free(ign->fb_tunnel_dev); 1343 err_alloc_dev: 1344 return err; 1345 } 1346 1347 static void __net_exit ip6gre_exit_net(struct net *net) 1348 { 1349 struct ip6gre_net *ign; 1350 LIST_HEAD(list); 1351 1352 ign = net_generic(net, ip6gre_net_id); 1353 rtnl_lock(); 1354 ip6gre_destroy_tunnels(ign, &list); 1355 unregister_netdevice_many(&list); 1356 rtnl_unlock(); 1357 } 1358 1359 static struct pernet_operations ip6gre_net_ops = { 1360 .init = ip6gre_init_net, 1361 .exit = ip6gre_exit_net, 1362 .id = &ip6gre_net_id, 1363 .size = sizeof(struct ip6gre_net), 1364 }; 1365 1366 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1367 { 1368 __be16 flags; 1369 1370 if (!data) 1371 return 0; 1372 1373 flags = 0; 1374 if (data[IFLA_GRE_IFLAGS]) 1375 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1376 if (data[IFLA_GRE_OFLAGS]) 1377 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1378 if (flags & (GRE_VERSION|GRE_ROUTING)) 1379 return -EINVAL; 1380 1381 return 0; 1382 } 1383 1384 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1385 { 1386 struct in6_addr daddr; 1387 1388 if (tb[IFLA_ADDRESS]) { 1389 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1390 return -EINVAL; 1391 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1392 return -EADDRNOTAVAIL; 1393 } 1394 1395 if (!data) 1396 goto out; 1397 1398 if (data[IFLA_GRE_REMOTE]) { 1399 nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1400 if (ipv6_addr_any(&daddr)) 1401 return -EINVAL; 1402 } 1403 1404 out: 1405 return ip6gre_tunnel_validate(tb, data); 1406 } 1407 1408 1409 static void ip6gre_netlink_parms(struct nlattr *data[], 1410 struct __ip6_tnl_parm *parms) 1411 { 1412 memset(parms, 0, sizeof(*parms)); 1413 1414 if (!data) 1415 return; 1416 1417 if (data[IFLA_GRE_LINK]) 1418 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1419 1420 if (data[IFLA_GRE_IFLAGS]) 1421 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1422 1423 if (data[IFLA_GRE_OFLAGS]) 1424 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1425 1426 if (data[IFLA_GRE_IKEY]) 1427 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1428 1429 if (data[IFLA_GRE_OKEY]) 1430 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1431 1432 if (data[IFLA_GRE_LOCAL]) 1433 nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr)); 1434 1435 if (data[IFLA_GRE_REMOTE]) 1436 nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1437 1438 if (data[IFLA_GRE_TTL]) 1439 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1440 1441 if (data[IFLA_GRE_ENCAP_LIMIT]) 1442 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1443 1444 if (data[IFLA_GRE_FLOWINFO]) 1445 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1446 1447 if (data[IFLA_GRE_FLAGS]) 1448 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1449 } 1450 1451 static int ip6gre_tap_init(struct net_device *dev) 1452 { 1453 struct ip6_tnl *tunnel; 1454 1455 tunnel = netdev_priv(dev); 1456 1457 tunnel->dev = dev; 1458 tunnel->net = dev_net(dev); 1459 strcpy(tunnel->parms.name, dev->name); 1460 1461 ip6gre_tnl_link_config(tunnel, 1); 1462 1463 dev->tstats = alloc_percpu(struct pcpu_tstats); 1464 if (!dev->tstats) 1465 return -ENOMEM; 1466 1467 return 0; 1468 } 1469 1470 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1471 .ndo_init = ip6gre_tap_init, 1472 .ndo_uninit = ip6gre_tunnel_uninit, 1473 .ndo_start_xmit = ip6gre_tunnel_xmit, 1474 .ndo_set_mac_address = eth_mac_addr, 1475 .ndo_validate_addr = eth_validate_addr, 1476 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1477 .ndo_get_stats64 = ip_tunnel_get_stats64, 1478 }; 1479 1480 static void ip6gre_tap_setup(struct net_device *dev) 1481 { 1482 1483 ether_setup(dev); 1484 1485 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1486 dev->destructor = ip6gre_dev_free; 1487 1488 dev->iflink = 0; 1489 dev->features |= NETIF_F_NETNS_LOCAL; 1490 } 1491 1492 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1493 struct nlattr *tb[], struct nlattr *data[]) 1494 { 1495 struct ip6_tnl *nt; 1496 struct net *net = dev_net(dev); 1497 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1498 int err; 1499 1500 nt = netdev_priv(dev); 1501 ip6gre_netlink_parms(data, &nt->parms); 1502 1503 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1504 return -EEXIST; 1505 1506 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1507 eth_hw_addr_random(dev); 1508 1509 nt->dev = dev; 1510 nt->net = dev_net(dev); 1511 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1512 1513 /* Can use a lockless transmit, unless we generate output sequences */ 1514 if (!(nt->parms.o_flags & GRE_SEQ)) 1515 dev->features |= NETIF_F_LLTX; 1516 1517 err = register_netdevice(dev); 1518 if (err) 1519 goto out; 1520 1521 dev_hold(dev); 1522 ip6gre_tunnel_link(ign, nt); 1523 1524 out: 1525 return err; 1526 } 1527 1528 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1529 struct nlattr *data[]) 1530 { 1531 struct ip6_tnl *t, *nt; 1532 struct net *net = dev_net(dev); 1533 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1534 struct __ip6_tnl_parm p; 1535 1536 if (dev == ign->fb_tunnel_dev) 1537 return -EINVAL; 1538 1539 nt = netdev_priv(dev); 1540 ip6gre_netlink_parms(data, &p); 1541 1542 t = ip6gre_tunnel_locate(net, &p, 0); 1543 1544 if (t) { 1545 if (t->dev != dev) 1546 return -EEXIST; 1547 } else { 1548 t = nt; 1549 1550 ip6gre_tunnel_unlink(ign, t); 1551 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1552 ip6gre_tunnel_link(ign, t); 1553 netdev_state_change(dev); 1554 } 1555 1556 return 0; 1557 } 1558 1559 static size_t ip6gre_get_size(const struct net_device *dev) 1560 { 1561 return 1562 /* IFLA_GRE_LINK */ 1563 nla_total_size(4) + 1564 /* IFLA_GRE_IFLAGS */ 1565 nla_total_size(2) + 1566 /* IFLA_GRE_OFLAGS */ 1567 nla_total_size(2) + 1568 /* IFLA_GRE_IKEY */ 1569 nla_total_size(4) + 1570 /* IFLA_GRE_OKEY */ 1571 nla_total_size(4) + 1572 /* IFLA_GRE_LOCAL */ 1573 nla_total_size(sizeof(struct in6_addr)) + 1574 /* IFLA_GRE_REMOTE */ 1575 nla_total_size(sizeof(struct in6_addr)) + 1576 /* IFLA_GRE_TTL */ 1577 nla_total_size(1) + 1578 /* IFLA_GRE_TOS */ 1579 nla_total_size(1) + 1580 /* IFLA_GRE_ENCAP_LIMIT */ 1581 nla_total_size(1) + 1582 /* IFLA_GRE_FLOWINFO */ 1583 nla_total_size(4) + 1584 /* IFLA_GRE_FLAGS */ 1585 nla_total_size(4) + 1586 0; 1587 } 1588 1589 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1590 { 1591 struct ip6_tnl *t = netdev_priv(dev); 1592 struct __ip6_tnl_parm *p = &t->parms; 1593 1594 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1595 nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) || 1596 nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) || 1597 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1598 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1599 nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->laddr) || 1600 nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->raddr) || 1601 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1602 /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/ 1603 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1604 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1605 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags)) 1606 goto nla_put_failure; 1607 return 0; 1608 1609 nla_put_failure: 1610 return -EMSGSIZE; 1611 } 1612 1613 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1614 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1615 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1616 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1617 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1618 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1619 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1620 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1621 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1622 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1623 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1624 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1625 }; 1626 1627 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1628 .kind = "ip6gre", 1629 .maxtype = IFLA_GRE_MAX, 1630 .policy = ip6gre_policy, 1631 .priv_size = sizeof(struct ip6_tnl), 1632 .setup = ip6gre_tunnel_setup, 1633 .validate = ip6gre_tunnel_validate, 1634 .newlink = ip6gre_newlink, 1635 .changelink = ip6gre_changelink, 1636 .get_size = ip6gre_get_size, 1637 .fill_info = ip6gre_fill_info, 1638 }; 1639 1640 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1641 .kind = "ip6gretap", 1642 .maxtype = IFLA_GRE_MAX, 1643 .policy = ip6gre_policy, 1644 .priv_size = sizeof(struct ip6_tnl), 1645 .setup = ip6gre_tap_setup, 1646 .validate = ip6gre_tap_validate, 1647 .newlink = ip6gre_newlink, 1648 .changelink = ip6gre_changelink, 1649 .get_size = ip6gre_get_size, 1650 .fill_info = ip6gre_fill_info, 1651 }; 1652 1653 /* 1654 * And now the modules code and kernel interface. 1655 */ 1656 1657 static int __init ip6gre_init(void) 1658 { 1659 int err; 1660 1661 pr_info("GRE over IPv6 tunneling driver\n"); 1662 1663 err = register_pernet_device(&ip6gre_net_ops); 1664 if (err < 0) 1665 return err; 1666 1667 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1668 if (err < 0) { 1669 pr_info("%s: can't add protocol\n", __func__); 1670 goto add_proto_failed; 1671 } 1672 1673 err = rtnl_link_register(&ip6gre_link_ops); 1674 if (err < 0) 1675 goto rtnl_link_failed; 1676 1677 err = rtnl_link_register(&ip6gre_tap_ops); 1678 if (err < 0) 1679 goto tap_ops_failed; 1680 1681 out: 1682 return err; 1683 1684 tap_ops_failed: 1685 rtnl_link_unregister(&ip6gre_link_ops); 1686 rtnl_link_failed: 1687 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1688 add_proto_failed: 1689 unregister_pernet_device(&ip6gre_net_ops); 1690 goto out; 1691 } 1692 1693 static void __exit ip6gre_fini(void) 1694 { 1695 rtnl_link_unregister(&ip6gre_tap_ops); 1696 rtnl_link_unregister(&ip6gre_link_ops); 1697 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1698 unregister_pernet_device(&ip6gre_net_ops); 1699 } 1700 1701 module_init(ip6gre_init); 1702 module_exit(ip6gre_fini); 1703 MODULE_LICENSE("GPL"); 1704 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1705 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1706 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1707 MODULE_ALIAS_NETDEV("ip6gre0"); 1708