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 ip6gre_tnl_link_config(nt, 1); 339 340 if (register_netdevice(dev) < 0) 341 goto failed_free; 342 343 /* Can use a lockless transmit, unless we generate output sequences */ 344 if (!(nt->parms.o_flags & GRE_SEQ)) 345 dev->features |= NETIF_F_LLTX; 346 347 dev_hold(dev); 348 ip6gre_tunnel_link(ign, nt); 349 return nt; 350 351 failed_free: 352 free_netdev(dev); 353 return NULL; 354 } 355 356 static void ip6gre_tunnel_uninit(struct net_device *dev) 357 { 358 struct net *net = dev_net(dev); 359 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 360 361 ip6gre_tunnel_unlink(ign, netdev_priv(dev)); 362 dev_put(dev); 363 } 364 365 366 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 367 u8 type, u8 code, int offset, __be32 info) 368 { 369 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 370 __be16 *p = (__be16 *)(skb->data + offset); 371 int grehlen = offset + 4; 372 struct ip6_tnl *t; 373 __be16 flags; 374 375 flags = p[0]; 376 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 377 if (flags&(GRE_VERSION|GRE_ROUTING)) 378 return; 379 if (flags&GRE_KEY) { 380 grehlen += 4; 381 if (flags&GRE_CSUM) 382 grehlen += 4; 383 } 384 } 385 386 /* If only 8 bytes returned, keyed message will be dropped here */ 387 if (!pskb_may_pull(skb, grehlen)) 388 return; 389 ipv6h = (const struct ipv6hdr *)skb->data; 390 p = (__be16 *)(skb->data + offset); 391 392 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 393 flags & GRE_KEY ? 394 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 395 p[1]); 396 if (t == NULL) 397 return; 398 399 switch (type) { 400 __u32 teli; 401 struct ipv6_tlv_tnl_enc_lim *tel; 402 __u32 mtu; 403 case ICMPV6_DEST_UNREACH: 404 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n", 405 t->parms.name); 406 break; 407 case ICMPV6_TIME_EXCEED: 408 if (code == ICMPV6_EXC_HOPLIMIT) { 409 net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 410 t->parms.name); 411 } 412 break; 413 case ICMPV6_PARAMPROB: 414 teli = 0; 415 if (code == ICMPV6_HDR_FIELD) 416 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 417 418 if (teli && teli == info - 2) { 419 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 420 if (tel->encap_limit == 0) { 421 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 422 t->parms.name); 423 } 424 } else { 425 net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 426 t->parms.name); 427 } 428 break; 429 case ICMPV6_PKT_TOOBIG: 430 mtu = info - offset; 431 if (mtu < IPV6_MIN_MTU) 432 mtu = IPV6_MIN_MTU; 433 t->dev->mtu = mtu; 434 break; 435 } 436 437 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 438 t->err_count++; 439 else 440 t->err_count = 1; 441 t->err_time = jiffies; 442 } 443 444 static int ip6gre_rcv(struct sk_buff *skb) 445 { 446 const struct ipv6hdr *ipv6h; 447 u8 *h; 448 __be16 flags; 449 __sum16 csum = 0; 450 __be32 key = 0; 451 u32 seqno = 0; 452 struct ip6_tnl *tunnel; 453 int offset = 4; 454 __be16 gre_proto; 455 int err; 456 457 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 458 goto drop; 459 460 ipv6h = ipv6_hdr(skb); 461 h = skb->data; 462 flags = *(__be16 *)h; 463 464 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 465 /* - Version must be 0. 466 - We do not support routing headers. 467 */ 468 if (flags&(GRE_VERSION|GRE_ROUTING)) 469 goto drop; 470 471 if (flags&GRE_CSUM) { 472 switch (skb->ip_summed) { 473 case CHECKSUM_COMPLETE: 474 csum = csum_fold(skb->csum); 475 if (!csum) 476 break; 477 /* fall through */ 478 case CHECKSUM_NONE: 479 skb->csum = 0; 480 csum = __skb_checksum_complete(skb); 481 skb->ip_summed = CHECKSUM_COMPLETE; 482 } 483 offset += 4; 484 } 485 if (flags&GRE_KEY) { 486 key = *(__be32 *)(h + offset); 487 offset += 4; 488 } 489 if (flags&GRE_SEQ) { 490 seqno = ntohl(*(__be32 *)(h + offset)); 491 offset += 4; 492 } 493 } 494 495 gre_proto = *(__be16 *)(h + 2); 496 497 tunnel = ip6gre_tunnel_lookup(skb->dev, 498 &ipv6h->saddr, &ipv6h->daddr, key, 499 gre_proto); 500 if (tunnel) { 501 struct pcpu_tstats *tstats; 502 503 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 504 goto drop; 505 506 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 507 tunnel->dev->stats.rx_dropped++; 508 goto drop; 509 } 510 511 secpath_reset(skb); 512 513 skb->protocol = gre_proto; 514 /* WCCP version 1 and 2 protocol decoding. 515 * - Change protocol to IP 516 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 517 */ 518 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 519 skb->protocol = htons(ETH_P_IP); 520 if ((*(h + offset) & 0xF0) != 0x40) 521 offset += 4; 522 } 523 524 skb->mac_header = skb->network_header; 525 __pskb_pull(skb, offset); 526 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 527 skb->pkt_type = PACKET_HOST; 528 529 if (((flags&GRE_CSUM) && csum) || 530 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 531 tunnel->dev->stats.rx_crc_errors++; 532 tunnel->dev->stats.rx_errors++; 533 goto drop; 534 } 535 if (tunnel->parms.i_flags&GRE_SEQ) { 536 if (!(flags&GRE_SEQ) || 537 (tunnel->i_seqno && 538 (s32)(seqno - tunnel->i_seqno) < 0)) { 539 tunnel->dev->stats.rx_fifo_errors++; 540 tunnel->dev->stats.rx_errors++; 541 goto drop; 542 } 543 tunnel->i_seqno = seqno + 1; 544 } 545 546 /* Warning: All skb pointers will be invalidated! */ 547 if (tunnel->dev->type == ARPHRD_ETHER) { 548 if (!pskb_may_pull(skb, ETH_HLEN)) { 549 tunnel->dev->stats.rx_length_errors++; 550 tunnel->dev->stats.rx_errors++; 551 goto drop; 552 } 553 554 ipv6h = ipv6_hdr(skb); 555 skb->protocol = eth_type_trans(skb, tunnel->dev); 556 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 557 } 558 559 __skb_tunnel_rx(skb, tunnel->dev); 560 561 skb_reset_network_header(skb); 562 563 err = IP6_ECN_decapsulate(ipv6h, skb); 564 if (unlikely(err)) { 565 if (log_ecn_error) 566 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 567 &ipv6h->saddr, 568 ipv6_get_dsfield(ipv6h)); 569 if (err > 1) { 570 ++tunnel->dev->stats.rx_frame_errors; 571 ++tunnel->dev->stats.rx_errors; 572 goto drop; 573 } 574 } 575 576 tstats = this_cpu_ptr(tunnel->dev->tstats); 577 u64_stats_update_begin(&tstats->syncp); 578 tstats->rx_packets++; 579 tstats->rx_bytes += skb->len; 580 u64_stats_update_end(&tstats->syncp); 581 582 netif_rx(skb); 583 584 return 0; 585 } 586 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 587 588 drop: 589 kfree_skb(skb); 590 return 0; 591 } 592 593 struct ipv6_tel_txoption { 594 struct ipv6_txoptions ops; 595 __u8 dst_opt[8]; 596 }; 597 598 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 599 { 600 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 601 602 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 603 opt->dst_opt[3] = 1; 604 opt->dst_opt[4] = encap_limit; 605 opt->dst_opt[5] = IPV6_TLV_PADN; 606 opt->dst_opt[6] = 1; 607 608 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 609 opt->ops.opt_nflen = 8; 610 } 611 612 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 613 struct net_device *dev, 614 __u8 dsfield, 615 struct flowi6 *fl6, 616 int encap_limit, 617 __u32 *pmtu) 618 { 619 struct net *net = dev_net(dev); 620 struct ip6_tnl *tunnel = netdev_priv(dev); 621 struct net_device *tdev; /* Device to other host */ 622 struct ipv6hdr *ipv6h; /* Our new IP header */ 623 unsigned int max_headroom; /* The extra header space needed */ 624 int gre_hlen; 625 struct ipv6_tel_txoption opt; 626 int mtu; 627 struct dst_entry *dst = NULL, *ndst = NULL; 628 struct net_device_stats *stats = &tunnel->dev->stats; 629 int err = -1; 630 u8 proto; 631 struct sk_buff *new_skb; 632 633 if (dev->type == ARPHRD_ETHER) 634 IPCB(skb)->flags = 0; 635 636 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 637 gre_hlen = 0; 638 ipv6h = (struct ipv6hdr *)skb->data; 639 fl6->daddr = ipv6h->daddr; 640 } else { 641 gre_hlen = tunnel->hlen; 642 fl6->daddr = tunnel->parms.raddr; 643 } 644 645 if (!fl6->flowi6_mark) 646 dst = ip6_tnl_dst_check(tunnel); 647 648 if (!dst) { 649 ndst = ip6_route_output(net, NULL, fl6); 650 651 if (ndst->error) 652 goto tx_err_link_failure; 653 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); 654 if (IS_ERR(ndst)) { 655 err = PTR_ERR(ndst); 656 ndst = NULL; 657 goto tx_err_link_failure; 658 } 659 dst = ndst; 660 } 661 662 tdev = dst->dev; 663 664 if (tdev == dev) { 665 stats->collisions++; 666 net_warn_ratelimited("%s: Local routing loop detected!\n", 667 tunnel->parms.name); 668 goto tx_err_dst_release; 669 } 670 671 mtu = dst_mtu(dst) - sizeof(*ipv6h); 672 if (encap_limit >= 0) { 673 max_headroom += 8; 674 mtu -= 8; 675 } 676 if (mtu < IPV6_MIN_MTU) 677 mtu = IPV6_MIN_MTU; 678 if (skb_dst(skb)) 679 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 680 if (skb->len > mtu) { 681 *pmtu = mtu; 682 err = -EMSGSIZE; 683 goto tx_err_dst_release; 684 } 685 686 if (tunnel->err_count > 0) { 687 if (time_before(jiffies, 688 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 689 tunnel->err_count--; 690 691 dst_link_failure(skb); 692 } else 693 tunnel->err_count = 0; 694 } 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 skb_dst_drop(skb); 713 714 if (fl6->flowi6_mark) { 715 skb_dst_set(skb, dst); 716 ndst = NULL; 717 } else { 718 skb_dst_set_noref(skb, dst); 719 } 720 721 proto = NEXTHDR_GRE; 722 if (encap_limit >= 0) { 723 init_tel_txopt(&opt, encap_limit); 724 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 725 } 726 727 skb_push(skb, gre_hlen); 728 skb_reset_network_header(skb); 729 skb_set_transport_header(skb, sizeof(*ipv6h)); 730 731 /* 732 * Push down and install the IP header. 733 */ 734 ipv6h = ipv6_hdr(skb); 735 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel); 736 ipv6h->hop_limit = tunnel->parms.hop_limit; 737 ipv6h->nexthdr = proto; 738 ipv6h->saddr = fl6->saddr; 739 ipv6h->daddr = fl6->daddr; 740 741 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 742 ((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ? 743 htons(ETH_P_TEB) : skb->protocol; 744 745 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 746 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 747 748 if (tunnel->parms.o_flags&GRE_SEQ) { 749 ++tunnel->o_seqno; 750 *ptr = htonl(tunnel->o_seqno); 751 ptr--; 752 } 753 if (tunnel->parms.o_flags&GRE_KEY) { 754 *ptr = tunnel->parms.o_key; 755 ptr--; 756 } 757 if (tunnel->parms.o_flags&GRE_CSUM) { 758 *ptr = 0; 759 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 760 skb->len - sizeof(struct ipv6hdr)); 761 } 762 } 763 764 ip6tunnel_xmit(skb, dev); 765 if (ndst) 766 ip6_tnl_dst_store(tunnel, ndst); 767 return 0; 768 tx_err_link_failure: 769 stats->tx_carrier_errors++; 770 dst_link_failure(skb); 771 tx_err_dst_release: 772 dst_release(ndst); 773 return err; 774 } 775 776 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 777 { 778 struct ip6_tnl *t = netdev_priv(dev); 779 const struct iphdr *iph = ip_hdr(skb); 780 int encap_limit = -1; 781 struct flowi6 fl6; 782 __u8 dsfield; 783 __u32 mtu; 784 int err; 785 786 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 787 encap_limit = t->parms.encap_limit; 788 789 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 790 fl6.flowi6_proto = IPPROTO_IPIP; 791 792 dsfield = ipv4_get_dsfield(iph); 793 794 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 795 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 796 & IPV6_TCLASS_MASK; 797 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 798 fl6.flowi6_mark = skb->mark; 799 800 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 801 if (err != 0) { 802 /* XXX: send ICMP error even if DF is not set. */ 803 if (err == -EMSGSIZE) 804 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 805 htonl(mtu)); 806 return -1; 807 } 808 809 return 0; 810 } 811 812 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 813 { 814 struct ip6_tnl *t = netdev_priv(dev); 815 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 816 int encap_limit = -1; 817 __u16 offset; 818 struct flowi6 fl6; 819 __u8 dsfield; 820 __u32 mtu; 821 int err; 822 823 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 824 return -1; 825 826 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 827 if (offset > 0) { 828 struct ipv6_tlv_tnl_enc_lim *tel; 829 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 830 if (tel->encap_limit == 0) { 831 icmpv6_send(skb, ICMPV6_PARAMPROB, 832 ICMPV6_HDR_FIELD, offset + 2); 833 return -1; 834 } 835 encap_limit = tel->encap_limit - 1; 836 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 837 encap_limit = t->parms.encap_limit; 838 839 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 840 fl6.flowi6_proto = IPPROTO_IPV6; 841 842 dsfield = ipv6_get_dsfield(ipv6h); 843 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 844 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 845 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 846 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 847 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 848 fl6.flowi6_mark = skb->mark; 849 850 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 851 if (err != 0) { 852 if (err == -EMSGSIZE) 853 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 854 return -1; 855 } 856 857 return 0; 858 } 859 860 /** 861 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 862 * @t: the outgoing tunnel device 863 * @hdr: IPv6 header from the incoming packet 864 * 865 * Description: 866 * Avoid trivial tunneling loop by checking that tunnel exit-point 867 * doesn't match source of incoming packet. 868 * 869 * Return: 870 * 1 if conflict, 871 * 0 else 872 **/ 873 874 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 875 const struct ipv6hdr *hdr) 876 { 877 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 878 } 879 880 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 881 { 882 struct ip6_tnl *t = netdev_priv(dev); 883 int encap_limit = -1; 884 struct flowi6 fl6; 885 __u32 mtu; 886 int err; 887 888 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 889 encap_limit = t->parms.encap_limit; 890 891 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 892 fl6.flowi6_proto = skb->protocol; 893 894 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 895 896 return err; 897 } 898 899 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 900 struct net_device *dev) 901 { 902 struct ip6_tnl *t = netdev_priv(dev); 903 struct net_device_stats *stats = &t->dev->stats; 904 int ret; 905 906 if (!ip6_tnl_xmit_ctl(t)) 907 goto tx_err; 908 909 switch (skb->protocol) { 910 case htons(ETH_P_IP): 911 ret = ip6gre_xmit_ipv4(skb, dev); 912 break; 913 case htons(ETH_P_IPV6): 914 ret = ip6gre_xmit_ipv6(skb, dev); 915 break; 916 default: 917 ret = ip6gre_xmit_other(skb, dev); 918 break; 919 } 920 921 if (ret < 0) 922 goto tx_err; 923 924 return NETDEV_TX_OK; 925 926 tx_err: 927 stats->tx_errors++; 928 stats->tx_dropped++; 929 kfree_skb(skb); 930 return NETDEV_TX_OK; 931 } 932 933 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 934 { 935 struct net_device *dev = t->dev; 936 struct __ip6_tnl_parm *p = &t->parms; 937 struct flowi6 *fl6 = &t->fl.u.ip6; 938 int addend = sizeof(struct ipv6hdr) + 4; 939 940 if (dev->type != ARPHRD_ETHER) { 941 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 942 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 943 } 944 945 /* Set up flowi template */ 946 fl6->saddr = p->laddr; 947 fl6->daddr = p->raddr; 948 fl6->flowi6_oif = p->link; 949 fl6->flowlabel = 0; 950 951 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 952 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 953 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 954 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 955 956 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 957 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 958 959 if (p->flags&IP6_TNL_F_CAP_XMIT && 960 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 961 dev->flags |= IFF_POINTOPOINT; 962 else 963 dev->flags &= ~IFF_POINTOPOINT; 964 965 dev->iflink = p->link; 966 967 /* Precalculate GRE options length */ 968 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 969 if (t->parms.o_flags&GRE_CSUM) 970 addend += 4; 971 if (t->parms.o_flags&GRE_KEY) 972 addend += 4; 973 if (t->parms.o_flags&GRE_SEQ) 974 addend += 4; 975 } 976 977 if (p->flags & IP6_TNL_F_CAP_XMIT) { 978 int strict = (ipv6_addr_type(&p->raddr) & 979 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 980 981 struct rt6_info *rt = rt6_lookup(dev_net(dev), 982 &p->raddr, &p->laddr, 983 p->link, strict); 984 985 if (rt == NULL) 986 return; 987 988 if (rt->dst.dev) { 989 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 990 991 if (set_mtu) { 992 dev->mtu = rt->dst.dev->mtu - addend; 993 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 994 dev->mtu -= 8; 995 996 if (dev->mtu < IPV6_MIN_MTU) 997 dev->mtu = IPV6_MIN_MTU; 998 } 999 } 1000 ip6_rt_put(rt); 1001 } 1002 1003 t->hlen = addend; 1004 } 1005 1006 static int ip6gre_tnl_change(struct ip6_tnl *t, 1007 const struct __ip6_tnl_parm *p, int set_mtu) 1008 { 1009 t->parms.laddr = p->laddr; 1010 t->parms.raddr = p->raddr; 1011 t->parms.flags = p->flags; 1012 t->parms.hop_limit = p->hop_limit; 1013 t->parms.encap_limit = p->encap_limit; 1014 t->parms.flowinfo = p->flowinfo; 1015 t->parms.link = p->link; 1016 t->parms.proto = p->proto; 1017 t->parms.i_key = p->i_key; 1018 t->parms.o_key = p->o_key; 1019 t->parms.i_flags = p->i_flags; 1020 t->parms.o_flags = p->o_flags; 1021 ip6_tnl_dst_reset(t); 1022 ip6gre_tnl_link_config(t, set_mtu); 1023 return 0; 1024 } 1025 1026 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1027 const struct ip6_tnl_parm2 *u) 1028 { 1029 p->laddr = u->laddr; 1030 p->raddr = u->raddr; 1031 p->flags = u->flags; 1032 p->hop_limit = u->hop_limit; 1033 p->encap_limit = u->encap_limit; 1034 p->flowinfo = u->flowinfo; 1035 p->link = u->link; 1036 p->i_key = u->i_key; 1037 p->o_key = u->o_key; 1038 p->i_flags = u->i_flags; 1039 p->o_flags = u->o_flags; 1040 memcpy(p->name, u->name, sizeof(u->name)); 1041 } 1042 1043 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1044 const struct __ip6_tnl_parm *p) 1045 { 1046 u->proto = IPPROTO_GRE; 1047 u->laddr = p->laddr; 1048 u->raddr = p->raddr; 1049 u->flags = p->flags; 1050 u->hop_limit = p->hop_limit; 1051 u->encap_limit = p->encap_limit; 1052 u->flowinfo = p->flowinfo; 1053 u->link = p->link; 1054 u->i_key = p->i_key; 1055 u->o_key = p->o_key; 1056 u->i_flags = p->i_flags; 1057 u->o_flags = p->o_flags; 1058 memcpy(u->name, p->name, sizeof(u->name)); 1059 } 1060 1061 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1062 struct ifreq *ifr, int cmd) 1063 { 1064 int err = 0; 1065 struct ip6_tnl_parm2 p; 1066 struct __ip6_tnl_parm p1; 1067 struct ip6_tnl *t; 1068 struct net *net = dev_net(dev); 1069 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1070 1071 switch (cmd) { 1072 case SIOCGETTUNNEL: 1073 t = NULL; 1074 if (dev == ign->fb_tunnel_dev) { 1075 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1076 err = -EFAULT; 1077 break; 1078 } 1079 ip6gre_tnl_parm_from_user(&p1, &p); 1080 t = ip6gre_tunnel_locate(net, &p1, 0); 1081 } 1082 if (t == NULL) 1083 t = netdev_priv(dev); 1084 memset(&p, 0, sizeof(p)); 1085 ip6gre_tnl_parm_to_user(&p, &t->parms); 1086 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1087 err = -EFAULT; 1088 break; 1089 1090 case SIOCADDTUNNEL: 1091 case SIOCCHGTUNNEL: 1092 err = -EPERM; 1093 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1094 goto done; 1095 1096 err = -EFAULT; 1097 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1098 goto done; 1099 1100 err = -EINVAL; 1101 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1102 goto done; 1103 1104 if (!(p.i_flags&GRE_KEY)) 1105 p.i_key = 0; 1106 if (!(p.o_flags&GRE_KEY)) 1107 p.o_key = 0; 1108 1109 ip6gre_tnl_parm_from_user(&p1, &p); 1110 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1111 1112 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1113 if (t != NULL) { 1114 if (t->dev != dev) { 1115 err = -EEXIST; 1116 break; 1117 } 1118 } else { 1119 t = netdev_priv(dev); 1120 1121 ip6gre_tunnel_unlink(ign, t); 1122 synchronize_net(); 1123 ip6gre_tnl_change(t, &p1, 1); 1124 ip6gre_tunnel_link(ign, t); 1125 netdev_state_change(dev); 1126 } 1127 } 1128 1129 if (t) { 1130 err = 0; 1131 1132 memset(&p, 0, sizeof(p)); 1133 ip6gre_tnl_parm_to_user(&p, &t->parms); 1134 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1135 err = -EFAULT; 1136 } else 1137 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1138 break; 1139 1140 case SIOCDELTUNNEL: 1141 err = -EPERM; 1142 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1143 goto done; 1144 1145 if (dev == ign->fb_tunnel_dev) { 1146 err = -EFAULT; 1147 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1148 goto done; 1149 err = -ENOENT; 1150 ip6gre_tnl_parm_from_user(&p1, &p); 1151 t = ip6gre_tunnel_locate(net, &p1, 0); 1152 if (t == NULL) 1153 goto done; 1154 err = -EPERM; 1155 if (t == netdev_priv(ign->fb_tunnel_dev)) 1156 goto done; 1157 dev = t->dev; 1158 } 1159 unregister_netdevice(dev); 1160 err = 0; 1161 break; 1162 1163 default: 1164 err = -EINVAL; 1165 } 1166 1167 done: 1168 return err; 1169 } 1170 1171 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1172 { 1173 struct ip6_tnl *tunnel = netdev_priv(dev); 1174 if (new_mtu < 68 || 1175 new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen) 1176 return -EINVAL; 1177 dev->mtu = new_mtu; 1178 return 0; 1179 } 1180 1181 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1182 unsigned short type, 1183 const void *daddr, const void *saddr, unsigned int len) 1184 { 1185 struct ip6_tnl *t = netdev_priv(dev); 1186 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1187 __be16 *p = (__be16 *)(ipv6h+1); 1188 1189 ip6_flow_hdr(ipv6h, 0, t->fl.u.ip6.flowlabel); 1190 ipv6h->hop_limit = t->parms.hop_limit; 1191 ipv6h->nexthdr = NEXTHDR_GRE; 1192 ipv6h->saddr = t->parms.laddr; 1193 ipv6h->daddr = t->parms.raddr; 1194 1195 p[0] = t->parms.o_flags; 1196 p[1] = htons(type); 1197 1198 /* 1199 * Set the source hardware address. 1200 */ 1201 1202 if (saddr) 1203 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1204 if (daddr) 1205 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1206 if (!ipv6_addr_any(&ipv6h->daddr)) 1207 return t->hlen; 1208 1209 return -t->hlen; 1210 } 1211 1212 static const struct header_ops ip6gre_header_ops = { 1213 .create = ip6gre_header, 1214 }; 1215 1216 static const struct net_device_ops ip6gre_netdev_ops = { 1217 .ndo_init = ip6gre_tunnel_init, 1218 .ndo_uninit = ip6gre_tunnel_uninit, 1219 .ndo_start_xmit = ip6gre_tunnel_xmit, 1220 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1221 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1222 .ndo_get_stats64 = ip_tunnel_get_stats64, 1223 }; 1224 1225 static void ip6gre_dev_free(struct net_device *dev) 1226 { 1227 free_percpu(dev->tstats); 1228 free_netdev(dev); 1229 } 1230 1231 static void ip6gre_tunnel_setup(struct net_device *dev) 1232 { 1233 struct ip6_tnl *t; 1234 1235 dev->netdev_ops = &ip6gre_netdev_ops; 1236 dev->destructor = ip6gre_dev_free; 1237 1238 dev->type = ARPHRD_IP6GRE; 1239 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1240 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1241 t = netdev_priv(dev); 1242 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1243 dev->mtu -= 8; 1244 dev->flags |= IFF_NOARP; 1245 dev->iflink = 0; 1246 dev->addr_len = sizeof(struct in6_addr); 1247 dev->features |= NETIF_F_NETNS_LOCAL; 1248 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1249 } 1250 1251 static int ip6gre_tunnel_init(struct net_device *dev) 1252 { 1253 struct ip6_tnl *tunnel; 1254 1255 tunnel = netdev_priv(dev); 1256 1257 tunnel->dev = dev; 1258 strcpy(tunnel->parms.name, dev->name); 1259 1260 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1261 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1262 1263 if (ipv6_addr_any(&tunnel->parms.raddr)) 1264 dev->header_ops = &ip6gre_header_ops; 1265 1266 dev->tstats = alloc_percpu(struct pcpu_tstats); 1267 if (!dev->tstats) 1268 return -ENOMEM; 1269 1270 return 0; 1271 } 1272 1273 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1274 { 1275 struct ip6_tnl *tunnel = netdev_priv(dev); 1276 1277 tunnel->dev = dev; 1278 strcpy(tunnel->parms.name, dev->name); 1279 1280 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1281 1282 dev_hold(dev); 1283 } 1284 1285 1286 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1287 .handler = ip6gre_rcv, 1288 .err_handler = ip6gre_err, 1289 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1290 }; 1291 1292 static void ip6gre_destroy_tunnels(struct ip6gre_net *ign, 1293 struct list_head *head) 1294 { 1295 int prio; 1296 1297 for (prio = 0; prio < 4; prio++) { 1298 int h; 1299 for (h = 0; h < HASH_SIZE; h++) { 1300 struct ip6_tnl *t; 1301 1302 t = rtnl_dereference(ign->tunnels[prio][h]); 1303 1304 while (t != NULL) { 1305 unregister_netdevice_queue(t->dev, head); 1306 t = rtnl_dereference(t->next); 1307 } 1308 } 1309 } 1310 } 1311 1312 static int __net_init ip6gre_init_net(struct net *net) 1313 { 1314 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1315 int err; 1316 1317 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1318 ip6gre_tunnel_setup); 1319 if (!ign->fb_tunnel_dev) { 1320 err = -ENOMEM; 1321 goto err_alloc_dev; 1322 } 1323 dev_net_set(ign->fb_tunnel_dev, net); 1324 1325 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1326 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1327 1328 err = register_netdev(ign->fb_tunnel_dev); 1329 if (err) 1330 goto err_reg_dev; 1331 1332 rcu_assign_pointer(ign->tunnels_wc[0], 1333 netdev_priv(ign->fb_tunnel_dev)); 1334 return 0; 1335 1336 err_reg_dev: 1337 ip6gre_dev_free(ign->fb_tunnel_dev); 1338 err_alloc_dev: 1339 return err; 1340 } 1341 1342 static void __net_exit ip6gre_exit_net(struct net *net) 1343 { 1344 struct ip6gre_net *ign; 1345 LIST_HEAD(list); 1346 1347 ign = net_generic(net, ip6gre_net_id); 1348 rtnl_lock(); 1349 ip6gre_destroy_tunnels(ign, &list); 1350 unregister_netdevice_many(&list); 1351 rtnl_unlock(); 1352 } 1353 1354 static struct pernet_operations ip6gre_net_ops = { 1355 .init = ip6gre_init_net, 1356 .exit = ip6gre_exit_net, 1357 .id = &ip6gre_net_id, 1358 .size = sizeof(struct ip6gre_net), 1359 }; 1360 1361 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1362 { 1363 __be16 flags; 1364 1365 if (!data) 1366 return 0; 1367 1368 flags = 0; 1369 if (data[IFLA_GRE_IFLAGS]) 1370 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1371 if (data[IFLA_GRE_OFLAGS]) 1372 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1373 if (flags & (GRE_VERSION|GRE_ROUTING)) 1374 return -EINVAL; 1375 1376 return 0; 1377 } 1378 1379 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1380 { 1381 struct in6_addr daddr; 1382 1383 if (tb[IFLA_ADDRESS]) { 1384 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1385 return -EINVAL; 1386 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1387 return -EADDRNOTAVAIL; 1388 } 1389 1390 if (!data) 1391 goto out; 1392 1393 if (data[IFLA_GRE_REMOTE]) { 1394 nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1395 if (ipv6_addr_any(&daddr)) 1396 return -EINVAL; 1397 } 1398 1399 out: 1400 return ip6gre_tunnel_validate(tb, data); 1401 } 1402 1403 1404 static void ip6gre_netlink_parms(struct nlattr *data[], 1405 struct __ip6_tnl_parm *parms) 1406 { 1407 memset(parms, 0, sizeof(*parms)); 1408 1409 if (!data) 1410 return; 1411 1412 if (data[IFLA_GRE_LINK]) 1413 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1414 1415 if (data[IFLA_GRE_IFLAGS]) 1416 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1417 1418 if (data[IFLA_GRE_OFLAGS]) 1419 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1420 1421 if (data[IFLA_GRE_IKEY]) 1422 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1423 1424 if (data[IFLA_GRE_OKEY]) 1425 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1426 1427 if (data[IFLA_GRE_LOCAL]) 1428 nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr)); 1429 1430 if (data[IFLA_GRE_REMOTE]) 1431 nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1432 1433 if (data[IFLA_GRE_TTL]) 1434 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1435 1436 if (data[IFLA_GRE_ENCAP_LIMIT]) 1437 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1438 1439 if (data[IFLA_GRE_FLOWINFO]) 1440 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1441 1442 if (data[IFLA_GRE_FLAGS]) 1443 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1444 } 1445 1446 static int ip6gre_tap_init(struct net_device *dev) 1447 { 1448 struct ip6_tnl *tunnel; 1449 1450 tunnel = netdev_priv(dev); 1451 1452 tunnel->dev = dev; 1453 strcpy(tunnel->parms.name, dev->name); 1454 1455 ip6gre_tnl_link_config(tunnel, 1); 1456 1457 dev->tstats = alloc_percpu(struct pcpu_tstats); 1458 if (!dev->tstats) 1459 return -ENOMEM; 1460 1461 return 0; 1462 } 1463 1464 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1465 .ndo_init = ip6gre_tap_init, 1466 .ndo_uninit = ip6gre_tunnel_uninit, 1467 .ndo_start_xmit = ip6gre_tunnel_xmit, 1468 .ndo_set_mac_address = eth_mac_addr, 1469 .ndo_validate_addr = eth_validate_addr, 1470 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1471 .ndo_get_stats64 = ip_tunnel_get_stats64, 1472 }; 1473 1474 static void ip6gre_tap_setup(struct net_device *dev) 1475 { 1476 1477 ether_setup(dev); 1478 1479 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1480 dev->destructor = ip6gre_dev_free; 1481 1482 dev->iflink = 0; 1483 dev->features |= NETIF_F_NETNS_LOCAL; 1484 } 1485 1486 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1487 struct nlattr *tb[], struct nlattr *data[]) 1488 { 1489 struct ip6_tnl *nt; 1490 struct net *net = dev_net(dev); 1491 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1492 int err; 1493 1494 nt = netdev_priv(dev); 1495 ip6gre_netlink_parms(data, &nt->parms); 1496 1497 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1498 return -EEXIST; 1499 1500 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1501 eth_hw_addr_random(dev); 1502 1503 nt->dev = dev; 1504 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1505 1506 /* Can use a lockless transmit, unless we generate output sequences */ 1507 if (!(nt->parms.o_flags & GRE_SEQ)) 1508 dev->features |= NETIF_F_LLTX; 1509 1510 err = register_netdevice(dev); 1511 if (err) 1512 goto out; 1513 1514 dev_hold(dev); 1515 ip6gre_tunnel_link(ign, nt); 1516 1517 out: 1518 return err; 1519 } 1520 1521 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1522 struct nlattr *data[]) 1523 { 1524 struct ip6_tnl *t, *nt; 1525 struct net *net = dev_net(dev); 1526 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1527 struct __ip6_tnl_parm p; 1528 1529 if (dev == ign->fb_tunnel_dev) 1530 return -EINVAL; 1531 1532 nt = netdev_priv(dev); 1533 ip6gre_netlink_parms(data, &p); 1534 1535 t = ip6gre_tunnel_locate(net, &p, 0); 1536 1537 if (t) { 1538 if (t->dev != dev) 1539 return -EEXIST; 1540 } else { 1541 t = nt; 1542 1543 ip6gre_tunnel_unlink(ign, t); 1544 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1545 ip6gre_tunnel_link(ign, t); 1546 netdev_state_change(dev); 1547 } 1548 1549 return 0; 1550 } 1551 1552 static size_t ip6gre_get_size(const struct net_device *dev) 1553 { 1554 return 1555 /* IFLA_GRE_LINK */ 1556 nla_total_size(4) + 1557 /* IFLA_GRE_IFLAGS */ 1558 nla_total_size(2) + 1559 /* IFLA_GRE_OFLAGS */ 1560 nla_total_size(2) + 1561 /* IFLA_GRE_IKEY */ 1562 nla_total_size(4) + 1563 /* IFLA_GRE_OKEY */ 1564 nla_total_size(4) + 1565 /* IFLA_GRE_LOCAL */ 1566 nla_total_size(sizeof(struct in6_addr)) + 1567 /* IFLA_GRE_REMOTE */ 1568 nla_total_size(sizeof(struct in6_addr)) + 1569 /* IFLA_GRE_TTL */ 1570 nla_total_size(1) + 1571 /* IFLA_GRE_TOS */ 1572 nla_total_size(1) + 1573 /* IFLA_GRE_ENCAP_LIMIT */ 1574 nla_total_size(1) + 1575 /* IFLA_GRE_FLOWINFO */ 1576 nla_total_size(4) + 1577 /* IFLA_GRE_FLAGS */ 1578 nla_total_size(4) + 1579 0; 1580 } 1581 1582 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1583 { 1584 struct ip6_tnl *t = netdev_priv(dev); 1585 struct __ip6_tnl_parm *p = &t->parms; 1586 1587 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1588 nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) || 1589 nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) || 1590 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1591 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1592 nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->laddr) || 1593 nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->raddr) || 1594 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1595 /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/ 1596 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1597 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1598 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags)) 1599 goto nla_put_failure; 1600 return 0; 1601 1602 nla_put_failure: 1603 return -EMSGSIZE; 1604 } 1605 1606 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1607 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1608 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1609 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1610 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1611 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1612 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1613 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1614 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1615 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1616 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1617 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1618 }; 1619 1620 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1621 .kind = "ip6gre", 1622 .maxtype = IFLA_GRE_MAX, 1623 .policy = ip6gre_policy, 1624 .priv_size = sizeof(struct ip6_tnl), 1625 .setup = ip6gre_tunnel_setup, 1626 .validate = ip6gre_tunnel_validate, 1627 .newlink = ip6gre_newlink, 1628 .changelink = ip6gre_changelink, 1629 .get_size = ip6gre_get_size, 1630 .fill_info = ip6gre_fill_info, 1631 }; 1632 1633 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1634 .kind = "ip6gretap", 1635 .maxtype = IFLA_GRE_MAX, 1636 .policy = ip6gre_policy, 1637 .priv_size = sizeof(struct ip6_tnl), 1638 .setup = ip6gre_tap_setup, 1639 .validate = ip6gre_tap_validate, 1640 .newlink = ip6gre_newlink, 1641 .changelink = ip6gre_changelink, 1642 .get_size = ip6gre_get_size, 1643 .fill_info = ip6gre_fill_info, 1644 }; 1645 1646 /* 1647 * And now the modules code and kernel interface. 1648 */ 1649 1650 static int __init ip6gre_init(void) 1651 { 1652 int err; 1653 1654 pr_info("GRE over IPv6 tunneling driver\n"); 1655 1656 err = register_pernet_device(&ip6gre_net_ops); 1657 if (err < 0) 1658 return err; 1659 1660 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1661 if (err < 0) { 1662 pr_info("%s: can't add protocol\n", __func__); 1663 goto add_proto_failed; 1664 } 1665 1666 err = rtnl_link_register(&ip6gre_link_ops); 1667 if (err < 0) 1668 goto rtnl_link_failed; 1669 1670 err = rtnl_link_register(&ip6gre_tap_ops); 1671 if (err < 0) 1672 goto tap_ops_failed; 1673 1674 out: 1675 return err; 1676 1677 tap_ops_failed: 1678 rtnl_link_unregister(&ip6gre_link_ops); 1679 rtnl_link_failed: 1680 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1681 add_proto_failed: 1682 unregister_pernet_device(&ip6gre_net_ops); 1683 goto out; 1684 } 1685 1686 static void __exit ip6gre_fini(void) 1687 { 1688 rtnl_link_unregister(&ip6gre_tap_ops); 1689 rtnl_link_unregister(&ip6gre_link_ops); 1690 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1691 unregister_pernet_device(&ip6gre_net_ops); 1692 } 1693 1694 module_init(ip6gre_init); 1695 module_exit(ip6gre_fini); 1696 MODULE_LICENSE("GPL"); 1697 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1698 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1699 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1700 MODULE_ALIAS_NETDEV("ip6gre0"); 1701