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/icmp.h> 42 #include <net/protocol.h> 43 #include <net/addrconf.h> 44 #include <net/arp.h> 45 #include <net/checksum.h> 46 #include <net/dsfield.h> 47 #include <net/inet_ecn.h> 48 #include <net/xfrm.h> 49 #include <net/net_namespace.h> 50 #include <net/netns/generic.h> 51 #include <net/rtnetlink.h> 52 53 #include <net/ipv6.h> 54 #include <net/ip6_fib.h> 55 #include <net/ip6_route.h> 56 #include <net/ip6_tunnel.h> 57 58 59 static bool log_ecn_error = true; 60 module_param(log_ecn_error, bool, 0644); 61 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 62 63 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) 64 #define IPV6_TCLASS_SHIFT 20 65 66 #define HASH_SIZE_SHIFT 5 67 #define HASH_SIZE (1 << HASH_SIZE_SHIFT) 68 69 static int ip6gre_net_id __read_mostly; 70 struct ip6gre_net { 71 struct ip6_tnl __rcu *tunnels[4][HASH_SIZE]; 72 73 struct net_device *fb_tunnel_dev; 74 }; 75 76 static struct rtnl_link_ops ip6gre_link_ops __read_mostly; 77 static int ip6gre_tunnel_init(struct net_device *dev); 78 static void ip6gre_tunnel_setup(struct net_device *dev); 79 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t); 80 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu); 81 82 /* Tunnel hash table */ 83 84 /* 85 4 hash tables: 86 87 3: (remote,local) 88 2: (remote,*) 89 1: (*,local) 90 0: (*,*) 91 92 We require exact key match i.e. if a key is present in packet 93 it will match only tunnel with the same key; if it is not present, 94 it will match only keyless tunnel. 95 96 All keysless packets, if not matched configured keyless tunnels 97 will match fallback tunnel. 98 */ 99 100 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 1)) 101 static u32 HASH_ADDR(const struct in6_addr *addr) 102 { 103 u32 hash = ipv6_addr_hash(addr); 104 105 return hash_32(hash, HASH_SIZE_SHIFT); 106 } 107 108 #define tunnels_r_l tunnels[3] 109 #define tunnels_r tunnels[2] 110 #define tunnels_l tunnels[1] 111 #define tunnels_wc tunnels[0] 112 /* 113 * Locking : hash tables are protected by RCU and RTNL 114 */ 115 116 #define for_each_ip_tunnel_rcu(start) \ 117 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) 118 119 /* often modified stats are per cpu, other are shared (netdev->stats) */ 120 struct pcpu_tstats { 121 u64 rx_packets; 122 u64 rx_bytes; 123 u64 tx_packets; 124 u64 tx_bytes; 125 struct u64_stats_sync syncp; 126 }; 127 128 static struct rtnl_link_stats64 *ip6gre_get_stats64(struct net_device *dev, 129 struct rtnl_link_stats64 *tot) 130 { 131 int i; 132 133 for_each_possible_cpu(i) { 134 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i); 135 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 136 unsigned int start; 137 138 do { 139 start = u64_stats_fetch_begin_bh(&tstats->syncp); 140 rx_packets = tstats->rx_packets; 141 tx_packets = tstats->tx_packets; 142 rx_bytes = tstats->rx_bytes; 143 tx_bytes = tstats->tx_bytes; 144 } while (u64_stats_fetch_retry_bh(&tstats->syncp, start)); 145 146 tot->rx_packets += rx_packets; 147 tot->tx_packets += tx_packets; 148 tot->rx_bytes += rx_bytes; 149 tot->tx_bytes += tx_bytes; 150 } 151 152 tot->multicast = dev->stats.multicast; 153 tot->rx_crc_errors = dev->stats.rx_crc_errors; 154 tot->rx_fifo_errors = dev->stats.rx_fifo_errors; 155 tot->rx_length_errors = dev->stats.rx_length_errors; 156 tot->rx_frame_errors = dev->stats.rx_frame_errors; 157 tot->rx_errors = dev->stats.rx_errors; 158 159 tot->tx_fifo_errors = dev->stats.tx_fifo_errors; 160 tot->tx_carrier_errors = dev->stats.tx_carrier_errors; 161 tot->tx_dropped = dev->stats.tx_dropped; 162 tot->tx_aborted_errors = dev->stats.tx_aborted_errors; 163 tot->tx_errors = dev->stats.tx_errors; 164 165 return tot; 166 } 167 168 /* Given src, dst and key, find appropriate for input tunnel. */ 169 170 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev, 171 const struct in6_addr *remote, const struct in6_addr *local, 172 __be32 key, __be16 gre_proto) 173 { 174 struct net *net = dev_net(dev); 175 int link = dev->ifindex; 176 unsigned int h0 = HASH_ADDR(remote); 177 unsigned int h1 = HASH_KEY(key); 178 struct ip6_tnl *t, *cand = NULL; 179 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 180 int dev_type = (gre_proto == htons(ETH_P_TEB)) ? 181 ARPHRD_ETHER : ARPHRD_IP6GRE; 182 int score, cand_score = 4; 183 184 for_each_ip_tunnel_rcu(ign->tunnels_r_l[h0 ^ h1]) { 185 if (!ipv6_addr_equal(local, &t->parms.laddr) || 186 !ipv6_addr_equal(remote, &t->parms.raddr) || 187 key != t->parms.i_key || 188 !(t->dev->flags & IFF_UP)) 189 continue; 190 191 if (t->dev->type != ARPHRD_IP6GRE && 192 t->dev->type != dev_type) 193 continue; 194 195 score = 0; 196 if (t->parms.link != link) 197 score |= 1; 198 if (t->dev->type != dev_type) 199 score |= 2; 200 if (score == 0) 201 return t; 202 203 if (score < cand_score) { 204 cand = t; 205 cand_score = score; 206 } 207 } 208 209 for_each_ip_tunnel_rcu(ign->tunnels_r[h0 ^ h1]) { 210 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 211 key != t->parms.i_key || 212 !(t->dev->flags & IFF_UP)) 213 continue; 214 215 if (t->dev->type != ARPHRD_IP6GRE && 216 t->dev->type != dev_type) 217 continue; 218 219 score = 0; 220 if (t->parms.link != link) 221 score |= 1; 222 if (t->dev->type != dev_type) 223 score |= 2; 224 if (score == 0) 225 return t; 226 227 if (score < cand_score) { 228 cand = t; 229 cand_score = score; 230 } 231 } 232 233 for_each_ip_tunnel_rcu(ign->tunnels_l[h1]) { 234 if ((!ipv6_addr_equal(local, &t->parms.laddr) && 235 (!ipv6_addr_equal(local, &t->parms.raddr) || 236 !ipv6_addr_is_multicast(local))) || 237 key != t->parms.i_key || 238 !(t->dev->flags & IFF_UP)) 239 continue; 240 241 if (t->dev->type != ARPHRD_IP6GRE && 242 t->dev->type != dev_type) 243 continue; 244 245 score = 0; 246 if (t->parms.link != link) 247 score |= 1; 248 if (t->dev->type != dev_type) 249 score |= 2; 250 if (score == 0) 251 return t; 252 253 if (score < cand_score) { 254 cand = t; 255 cand_score = score; 256 } 257 } 258 259 for_each_ip_tunnel_rcu(ign->tunnels_wc[h1]) { 260 if (t->parms.i_key != key || 261 !(t->dev->flags & IFF_UP)) 262 continue; 263 264 if (t->dev->type != ARPHRD_IP6GRE && 265 t->dev->type != dev_type) 266 continue; 267 268 score = 0; 269 if (t->parms.link != link) 270 score |= 1; 271 if (t->dev->type != dev_type) 272 score |= 2; 273 if (score == 0) 274 return t; 275 276 if (score < cand_score) { 277 cand = t; 278 cand_score = score; 279 } 280 } 281 282 if (cand != NULL) 283 return cand; 284 285 dev = ign->fb_tunnel_dev; 286 if (dev->flags & IFF_UP) 287 return netdev_priv(dev); 288 289 return NULL; 290 } 291 292 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign, 293 const struct __ip6_tnl_parm *p) 294 { 295 const struct in6_addr *remote = &p->raddr; 296 const struct in6_addr *local = &p->laddr; 297 unsigned int h = HASH_KEY(p->i_key); 298 int prio = 0; 299 300 if (!ipv6_addr_any(local)) 301 prio |= 1; 302 if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) { 303 prio |= 2; 304 h ^= HASH_ADDR(remote); 305 } 306 307 return &ign->tunnels[prio][h]; 308 } 309 310 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign, 311 const struct ip6_tnl *t) 312 { 313 return __ip6gre_bucket(ign, &t->parms); 314 } 315 316 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t) 317 { 318 struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t); 319 320 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 321 rcu_assign_pointer(*tp, t); 322 } 323 324 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t) 325 { 326 struct ip6_tnl __rcu **tp; 327 struct ip6_tnl *iter; 328 329 for (tp = ip6gre_bucket(ign, t); 330 (iter = rtnl_dereference(*tp)) != NULL; 331 tp = &iter->next) { 332 if (t == iter) { 333 rcu_assign_pointer(*tp, t->next); 334 break; 335 } 336 } 337 } 338 339 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net, 340 const struct __ip6_tnl_parm *parms, 341 int type) 342 { 343 const struct in6_addr *remote = &parms->raddr; 344 const struct in6_addr *local = &parms->laddr; 345 __be32 key = parms->i_key; 346 int link = parms->link; 347 struct ip6_tnl *t; 348 struct ip6_tnl __rcu **tp; 349 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 350 351 for (tp = __ip6gre_bucket(ign, parms); 352 (t = rtnl_dereference(*tp)) != NULL; 353 tp = &t->next) 354 if (ipv6_addr_equal(local, &t->parms.laddr) && 355 ipv6_addr_equal(remote, &t->parms.raddr) && 356 key == t->parms.i_key && 357 link == t->parms.link && 358 type == t->dev->type) 359 break; 360 361 return t; 362 } 363 364 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, 365 const struct __ip6_tnl_parm *parms, int create) 366 { 367 struct ip6_tnl *t, *nt; 368 struct net_device *dev; 369 char name[IFNAMSIZ]; 370 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 371 372 t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE); 373 if (t || !create) 374 return t; 375 376 if (parms->name[0]) 377 strlcpy(name, parms->name, IFNAMSIZ); 378 else 379 strcpy(name, "ip6gre%d"); 380 381 dev = alloc_netdev(sizeof(*t), name, ip6gre_tunnel_setup); 382 if (!dev) 383 return NULL; 384 385 dev_net_set(dev, net); 386 387 nt = netdev_priv(dev); 388 nt->parms = *parms; 389 dev->rtnl_link_ops = &ip6gre_link_ops; 390 391 nt->dev = dev; 392 ip6gre_tnl_link_config(nt, 1); 393 394 if (register_netdevice(dev) < 0) 395 goto failed_free; 396 397 /* Can use a lockless transmit, unless we generate output sequences */ 398 if (!(nt->parms.o_flags & GRE_SEQ)) 399 dev->features |= NETIF_F_LLTX; 400 401 dev_hold(dev); 402 ip6gre_tunnel_link(ign, nt); 403 return nt; 404 405 failed_free: 406 free_netdev(dev); 407 return NULL; 408 } 409 410 static void ip6gre_tunnel_uninit(struct net_device *dev) 411 { 412 struct net *net = dev_net(dev); 413 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 414 415 ip6gre_tunnel_unlink(ign, netdev_priv(dev)); 416 dev_put(dev); 417 } 418 419 420 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 421 u8 type, u8 code, int offset, __be32 info) 422 { 423 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 424 __be16 *p = (__be16 *)(skb->data + offset); 425 int grehlen = offset + 4; 426 struct ip6_tnl *t; 427 __be16 flags; 428 429 flags = p[0]; 430 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 431 if (flags&(GRE_VERSION|GRE_ROUTING)) 432 return; 433 if (flags&GRE_KEY) { 434 grehlen += 4; 435 if (flags&GRE_CSUM) 436 grehlen += 4; 437 } 438 } 439 440 /* If only 8 bytes returned, keyed message will be dropped here */ 441 if (!pskb_may_pull(skb, grehlen)) 442 return; 443 ipv6h = (const struct ipv6hdr *)skb->data; 444 p = (__be16 *)(skb->data + offset); 445 446 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 447 flags & GRE_KEY ? 448 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 449 p[1]); 450 if (t == NULL) 451 return; 452 453 switch (type) { 454 __u32 teli; 455 struct ipv6_tlv_tnl_enc_lim *tel; 456 __u32 mtu; 457 case ICMPV6_DEST_UNREACH: 458 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n", 459 t->parms.name); 460 break; 461 case ICMPV6_TIME_EXCEED: 462 if (code == ICMPV6_EXC_HOPLIMIT) { 463 net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 464 t->parms.name); 465 } 466 break; 467 case ICMPV6_PARAMPROB: 468 teli = 0; 469 if (code == ICMPV6_HDR_FIELD) 470 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 471 472 if (teli && teli == info - 2) { 473 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 474 if (tel->encap_limit == 0) { 475 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 476 t->parms.name); 477 } 478 } else { 479 net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 480 t->parms.name); 481 } 482 break; 483 case ICMPV6_PKT_TOOBIG: 484 mtu = info - offset; 485 if (mtu < IPV6_MIN_MTU) 486 mtu = IPV6_MIN_MTU; 487 t->dev->mtu = mtu; 488 break; 489 } 490 491 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 492 t->err_count++; 493 else 494 t->err_count = 1; 495 t->err_time = jiffies; 496 } 497 498 static int ip6gre_rcv(struct sk_buff *skb) 499 { 500 const struct ipv6hdr *ipv6h; 501 u8 *h; 502 __be16 flags; 503 __sum16 csum = 0; 504 __be32 key = 0; 505 u32 seqno = 0; 506 struct ip6_tnl *tunnel; 507 int offset = 4; 508 __be16 gre_proto; 509 int err; 510 511 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 512 goto drop; 513 514 ipv6h = ipv6_hdr(skb); 515 h = skb->data; 516 flags = *(__be16 *)h; 517 518 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 519 /* - Version must be 0. 520 - We do not support routing headers. 521 */ 522 if (flags&(GRE_VERSION|GRE_ROUTING)) 523 goto drop; 524 525 if (flags&GRE_CSUM) { 526 switch (skb->ip_summed) { 527 case CHECKSUM_COMPLETE: 528 csum = csum_fold(skb->csum); 529 if (!csum) 530 break; 531 /* fall through */ 532 case CHECKSUM_NONE: 533 skb->csum = 0; 534 csum = __skb_checksum_complete(skb); 535 skb->ip_summed = CHECKSUM_COMPLETE; 536 } 537 offset += 4; 538 } 539 if (flags&GRE_KEY) { 540 key = *(__be32 *)(h + offset); 541 offset += 4; 542 } 543 if (flags&GRE_SEQ) { 544 seqno = ntohl(*(__be32 *)(h + offset)); 545 offset += 4; 546 } 547 } 548 549 gre_proto = *(__be16 *)(h + 2); 550 551 tunnel = ip6gre_tunnel_lookup(skb->dev, 552 &ipv6h->saddr, &ipv6h->daddr, key, 553 gre_proto); 554 if (tunnel) { 555 struct pcpu_tstats *tstats; 556 557 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 558 goto drop; 559 560 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 561 tunnel->dev->stats.rx_dropped++; 562 goto drop; 563 } 564 565 secpath_reset(skb); 566 567 skb->protocol = gre_proto; 568 /* WCCP version 1 and 2 protocol decoding. 569 * - Change protocol to IP 570 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 571 */ 572 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 573 skb->protocol = htons(ETH_P_IP); 574 if ((*(h + offset) & 0xF0) != 0x40) 575 offset += 4; 576 } 577 578 skb->mac_header = skb->network_header; 579 __pskb_pull(skb, offset); 580 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 581 skb->pkt_type = PACKET_HOST; 582 583 if (((flags&GRE_CSUM) && csum) || 584 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 585 tunnel->dev->stats.rx_crc_errors++; 586 tunnel->dev->stats.rx_errors++; 587 goto drop; 588 } 589 if (tunnel->parms.i_flags&GRE_SEQ) { 590 if (!(flags&GRE_SEQ) || 591 (tunnel->i_seqno && 592 (s32)(seqno - tunnel->i_seqno) < 0)) { 593 tunnel->dev->stats.rx_fifo_errors++; 594 tunnel->dev->stats.rx_errors++; 595 goto drop; 596 } 597 tunnel->i_seqno = seqno + 1; 598 } 599 600 /* Warning: All skb pointers will be invalidated! */ 601 if (tunnel->dev->type == ARPHRD_ETHER) { 602 if (!pskb_may_pull(skb, ETH_HLEN)) { 603 tunnel->dev->stats.rx_length_errors++; 604 tunnel->dev->stats.rx_errors++; 605 goto drop; 606 } 607 608 ipv6h = ipv6_hdr(skb); 609 skb->protocol = eth_type_trans(skb, tunnel->dev); 610 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 611 } 612 613 __skb_tunnel_rx(skb, tunnel->dev); 614 615 skb_reset_network_header(skb); 616 617 err = IP6_ECN_decapsulate(ipv6h, skb); 618 if (unlikely(err)) { 619 if (log_ecn_error) 620 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 621 &ipv6h->saddr, 622 ipv6_get_dsfield(ipv6h)); 623 if (err > 1) { 624 ++tunnel->dev->stats.rx_frame_errors; 625 ++tunnel->dev->stats.rx_errors; 626 goto drop; 627 } 628 } 629 630 tstats = this_cpu_ptr(tunnel->dev->tstats); 631 u64_stats_update_begin(&tstats->syncp); 632 tstats->rx_packets++; 633 tstats->rx_bytes += skb->len; 634 u64_stats_update_end(&tstats->syncp); 635 636 netif_rx(skb); 637 638 return 0; 639 } 640 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 641 642 drop: 643 kfree_skb(skb); 644 return 0; 645 } 646 647 struct ipv6_tel_txoption { 648 struct ipv6_txoptions ops; 649 __u8 dst_opt[8]; 650 }; 651 652 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 653 { 654 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 655 656 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 657 opt->dst_opt[3] = 1; 658 opt->dst_opt[4] = encap_limit; 659 opt->dst_opt[5] = IPV6_TLV_PADN; 660 opt->dst_opt[6] = 1; 661 662 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 663 opt->ops.opt_nflen = 8; 664 } 665 666 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 667 struct net_device *dev, 668 __u8 dsfield, 669 struct flowi6 *fl6, 670 int encap_limit, 671 __u32 *pmtu) 672 { 673 struct net *net = dev_net(dev); 674 struct ip6_tnl *tunnel = netdev_priv(dev); 675 struct net_device *tdev; /* Device to other host */ 676 struct ipv6hdr *ipv6h; /* Our new IP header */ 677 unsigned int max_headroom; /* The extra header space needed */ 678 int gre_hlen; 679 struct ipv6_tel_txoption opt; 680 int mtu; 681 struct dst_entry *dst = NULL, *ndst = NULL; 682 struct net_device_stats *stats = &tunnel->dev->stats; 683 int err = -1; 684 u8 proto; 685 int pkt_len; 686 struct sk_buff *new_skb; 687 688 if (dev->type == ARPHRD_ETHER) 689 IPCB(skb)->flags = 0; 690 691 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 692 gre_hlen = 0; 693 ipv6h = (struct ipv6hdr *)skb->data; 694 fl6->daddr = ipv6h->daddr; 695 } else { 696 gre_hlen = tunnel->hlen; 697 fl6->daddr = tunnel->parms.raddr; 698 } 699 700 if (!fl6->flowi6_mark) 701 dst = ip6_tnl_dst_check(tunnel); 702 703 if (!dst) { 704 ndst = ip6_route_output(net, NULL, fl6); 705 706 if (ndst->error) 707 goto tx_err_link_failure; 708 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); 709 if (IS_ERR(ndst)) { 710 err = PTR_ERR(ndst); 711 ndst = NULL; 712 goto tx_err_link_failure; 713 } 714 dst = ndst; 715 } 716 717 tdev = dst->dev; 718 719 if (tdev == dev) { 720 stats->collisions++; 721 net_warn_ratelimited("%s: Local routing loop detected!\n", 722 tunnel->parms.name); 723 goto tx_err_dst_release; 724 } 725 726 mtu = dst_mtu(dst) - sizeof(*ipv6h); 727 if (encap_limit >= 0) { 728 max_headroom += 8; 729 mtu -= 8; 730 } 731 if (mtu < IPV6_MIN_MTU) 732 mtu = IPV6_MIN_MTU; 733 if (skb_dst(skb)) 734 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 735 if (skb->len > mtu) { 736 *pmtu = mtu; 737 err = -EMSGSIZE; 738 goto tx_err_dst_release; 739 } 740 741 if (tunnel->err_count > 0) { 742 if (time_before(jiffies, 743 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 744 tunnel->err_count--; 745 746 dst_link_failure(skb); 747 } else 748 tunnel->err_count = 0; 749 } 750 751 max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; 752 753 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 754 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 755 new_skb = skb_realloc_headroom(skb, max_headroom); 756 if (max_headroom > dev->needed_headroom) 757 dev->needed_headroom = max_headroom; 758 if (!new_skb) 759 goto tx_err_dst_release; 760 761 if (skb->sk) 762 skb_set_owner_w(new_skb, skb->sk); 763 consume_skb(skb); 764 skb = new_skb; 765 } 766 767 skb_dst_drop(skb); 768 769 if (fl6->flowi6_mark) { 770 skb_dst_set(skb, dst); 771 ndst = NULL; 772 } else { 773 skb_dst_set_noref(skb, dst); 774 } 775 776 skb->transport_header = skb->network_header; 777 778 proto = NEXTHDR_GRE; 779 if (encap_limit >= 0) { 780 init_tel_txopt(&opt, encap_limit); 781 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 782 } 783 784 skb_push(skb, gre_hlen); 785 skb_reset_network_header(skb); 786 787 /* 788 * Push down and install the IP header. 789 */ 790 ipv6h = ipv6_hdr(skb); 791 *(__be32 *)ipv6h = fl6->flowlabel | htonl(0x60000000); 792 dsfield = INET_ECN_encapsulate(0, dsfield); 793 ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield); 794 ipv6h->hop_limit = tunnel->parms.hop_limit; 795 ipv6h->nexthdr = proto; 796 ipv6h->saddr = fl6->saddr; 797 ipv6h->daddr = fl6->daddr; 798 799 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 800 ((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ? 801 htons(ETH_P_TEB) : skb->protocol; 802 803 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 804 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 805 806 if (tunnel->parms.o_flags&GRE_SEQ) { 807 ++tunnel->o_seqno; 808 *ptr = htonl(tunnel->o_seqno); 809 ptr--; 810 } 811 if (tunnel->parms.o_flags&GRE_KEY) { 812 *ptr = tunnel->parms.o_key; 813 ptr--; 814 } 815 if (tunnel->parms.o_flags&GRE_CSUM) { 816 *ptr = 0; 817 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 818 skb->len - sizeof(struct ipv6hdr)); 819 } 820 } 821 822 nf_reset(skb); 823 pkt_len = skb->len; 824 err = ip6_local_out(skb); 825 826 if (net_xmit_eval(err) == 0) { 827 struct pcpu_tstats *tstats = this_cpu_ptr(tunnel->dev->tstats); 828 829 tstats->tx_bytes += pkt_len; 830 tstats->tx_packets++; 831 } else { 832 stats->tx_errors++; 833 stats->tx_aborted_errors++; 834 } 835 836 if (ndst) 837 ip6_tnl_dst_store(tunnel, ndst); 838 839 return 0; 840 tx_err_link_failure: 841 stats->tx_carrier_errors++; 842 dst_link_failure(skb); 843 tx_err_dst_release: 844 dst_release(ndst); 845 return err; 846 } 847 848 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 849 { 850 struct ip6_tnl *t = netdev_priv(dev); 851 const struct iphdr *iph = ip_hdr(skb); 852 int encap_limit = -1; 853 struct flowi6 fl6; 854 __u8 dsfield; 855 __u32 mtu; 856 int err; 857 858 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 859 encap_limit = t->parms.encap_limit; 860 861 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 862 fl6.flowi6_proto = IPPROTO_IPIP; 863 864 dsfield = ipv4_get_dsfield(iph); 865 866 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 867 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 868 & IPV6_TCLASS_MASK; 869 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 870 fl6.flowi6_mark = skb->mark; 871 872 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 873 if (err != 0) { 874 /* XXX: send ICMP error even if DF is not set. */ 875 if (err == -EMSGSIZE) 876 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 877 htonl(mtu)); 878 return -1; 879 } 880 881 return 0; 882 } 883 884 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 885 { 886 struct ip6_tnl *t = netdev_priv(dev); 887 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 888 int encap_limit = -1; 889 __u16 offset; 890 struct flowi6 fl6; 891 __u8 dsfield; 892 __u32 mtu; 893 int err; 894 895 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 896 return -1; 897 898 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 899 if (offset > 0) { 900 struct ipv6_tlv_tnl_enc_lim *tel; 901 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 902 if (tel->encap_limit == 0) { 903 icmpv6_send(skb, ICMPV6_PARAMPROB, 904 ICMPV6_HDR_FIELD, offset + 2); 905 return -1; 906 } 907 encap_limit = tel->encap_limit - 1; 908 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 909 encap_limit = t->parms.encap_limit; 910 911 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 912 fl6.flowi6_proto = IPPROTO_IPV6; 913 914 dsfield = ipv6_get_dsfield(ipv6h); 915 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 916 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 917 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 918 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 919 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 920 fl6.flowi6_mark = skb->mark; 921 922 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 923 if (err != 0) { 924 if (err == -EMSGSIZE) 925 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 926 return -1; 927 } 928 929 return 0; 930 } 931 932 /** 933 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 934 * @t: the outgoing tunnel device 935 * @hdr: IPv6 header from the incoming packet 936 * 937 * Description: 938 * Avoid trivial tunneling loop by checking that tunnel exit-point 939 * doesn't match source of incoming packet. 940 * 941 * Return: 942 * 1 if conflict, 943 * 0 else 944 **/ 945 946 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 947 const struct ipv6hdr *hdr) 948 { 949 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 950 } 951 952 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 953 { 954 struct ip6_tnl *t = netdev_priv(dev); 955 int encap_limit = -1; 956 struct flowi6 fl6; 957 __u32 mtu; 958 int err; 959 960 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 961 encap_limit = t->parms.encap_limit; 962 963 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 964 fl6.flowi6_proto = skb->protocol; 965 966 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 967 968 return err; 969 } 970 971 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 972 struct net_device *dev) 973 { 974 struct ip6_tnl *t = netdev_priv(dev); 975 struct net_device_stats *stats = &t->dev->stats; 976 int ret; 977 978 if (!ip6_tnl_xmit_ctl(t)) 979 return -1; 980 981 switch (skb->protocol) { 982 case htons(ETH_P_IP): 983 ret = ip6gre_xmit_ipv4(skb, dev); 984 break; 985 case htons(ETH_P_IPV6): 986 ret = ip6gre_xmit_ipv6(skb, dev); 987 break; 988 default: 989 ret = ip6gre_xmit_other(skb, dev); 990 break; 991 } 992 993 if (ret < 0) 994 goto tx_err; 995 996 return NETDEV_TX_OK; 997 998 tx_err: 999 stats->tx_errors++; 1000 stats->tx_dropped++; 1001 kfree_skb(skb); 1002 return NETDEV_TX_OK; 1003 } 1004 1005 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 1006 { 1007 struct net_device *dev = t->dev; 1008 struct __ip6_tnl_parm *p = &t->parms; 1009 struct flowi6 *fl6 = &t->fl.u.ip6; 1010 int addend = sizeof(struct ipv6hdr) + 4; 1011 1012 if (dev->type != ARPHRD_ETHER) { 1013 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 1014 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 1015 } 1016 1017 /* Set up flowi template */ 1018 fl6->saddr = p->laddr; 1019 fl6->daddr = p->raddr; 1020 fl6->flowi6_oif = p->link; 1021 fl6->flowlabel = 0; 1022 1023 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1024 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1025 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1026 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1027 1028 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1029 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1030 1031 if (p->flags&IP6_TNL_F_CAP_XMIT && 1032 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 1033 dev->flags |= IFF_POINTOPOINT; 1034 else 1035 dev->flags &= ~IFF_POINTOPOINT; 1036 1037 dev->iflink = p->link; 1038 1039 /* Precalculate GRE options length */ 1040 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 1041 if (t->parms.o_flags&GRE_CSUM) 1042 addend += 4; 1043 if (t->parms.o_flags&GRE_KEY) 1044 addend += 4; 1045 if (t->parms.o_flags&GRE_SEQ) 1046 addend += 4; 1047 } 1048 1049 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1050 int strict = (ipv6_addr_type(&p->raddr) & 1051 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1052 1053 struct rt6_info *rt = rt6_lookup(dev_net(dev), 1054 &p->raddr, &p->laddr, 1055 p->link, strict); 1056 1057 if (rt == NULL) 1058 return; 1059 1060 if (rt->dst.dev) { 1061 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 1062 1063 if (set_mtu) { 1064 dev->mtu = rt->dst.dev->mtu - addend; 1065 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1066 dev->mtu -= 8; 1067 1068 if (dev->mtu < IPV6_MIN_MTU) 1069 dev->mtu = IPV6_MIN_MTU; 1070 } 1071 } 1072 dst_release(&rt->dst); 1073 } 1074 1075 t->hlen = addend; 1076 } 1077 1078 static int ip6gre_tnl_change(struct ip6_tnl *t, 1079 const struct __ip6_tnl_parm *p, int set_mtu) 1080 { 1081 t->parms.laddr = p->laddr; 1082 t->parms.raddr = p->raddr; 1083 t->parms.flags = p->flags; 1084 t->parms.hop_limit = p->hop_limit; 1085 t->parms.encap_limit = p->encap_limit; 1086 t->parms.flowinfo = p->flowinfo; 1087 t->parms.link = p->link; 1088 t->parms.proto = p->proto; 1089 t->parms.i_key = p->i_key; 1090 t->parms.o_key = p->o_key; 1091 t->parms.i_flags = p->i_flags; 1092 t->parms.o_flags = p->o_flags; 1093 ip6_tnl_dst_reset(t); 1094 ip6gre_tnl_link_config(t, set_mtu); 1095 return 0; 1096 } 1097 1098 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1099 const struct ip6_tnl_parm2 *u) 1100 { 1101 p->laddr = u->laddr; 1102 p->raddr = u->raddr; 1103 p->flags = u->flags; 1104 p->hop_limit = u->hop_limit; 1105 p->encap_limit = u->encap_limit; 1106 p->flowinfo = u->flowinfo; 1107 p->link = u->link; 1108 p->i_key = u->i_key; 1109 p->o_key = u->o_key; 1110 p->i_flags = u->i_flags; 1111 p->o_flags = u->o_flags; 1112 memcpy(p->name, u->name, sizeof(u->name)); 1113 } 1114 1115 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1116 const struct __ip6_tnl_parm *p) 1117 { 1118 u->proto = IPPROTO_GRE; 1119 u->laddr = p->laddr; 1120 u->raddr = p->raddr; 1121 u->flags = p->flags; 1122 u->hop_limit = p->hop_limit; 1123 u->encap_limit = p->encap_limit; 1124 u->flowinfo = p->flowinfo; 1125 u->link = p->link; 1126 u->i_key = p->i_key; 1127 u->o_key = p->o_key; 1128 u->i_flags = p->i_flags; 1129 u->o_flags = p->o_flags; 1130 memcpy(u->name, p->name, sizeof(u->name)); 1131 } 1132 1133 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1134 struct ifreq *ifr, int cmd) 1135 { 1136 int err = 0; 1137 struct ip6_tnl_parm2 p; 1138 struct __ip6_tnl_parm p1; 1139 struct ip6_tnl *t; 1140 struct net *net = dev_net(dev); 1141 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1142 1143 switch (cmd) { 1144 case SIOCGETTUNNEL: 1145 t = NULL; 1146 if (dev == ign->fb_tunnel_dev) { 1147 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1148 err = -EFAULT; 1149 break; 1150 } 1151 ip6gre_tnl_parm_from_user(&p1, &p); 1152 t = ip6gre_tunnel_locate(net, &p1, 0); 1153 } 1154 if (t == NULL) 1155 t = netdev_priv(dev); 1156 ip6gre_tnl_parm_to_user(&p, &t->parms); 1157 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1158 err = -EFAULT; 1159 break; 1160 1161 case SIOCADDTUNNEL: 1162 case SIOCCHGTUNNEL: 1163 err = -EPERM; 1164 if (!capable(CAP_NET_ADMIN)) 1165 goto done; 1166 1167 err = -EFAULT; 1168 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1169 goto done; 1170 1171 err = -EINVAL; 1172 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1173 goto done; 1174 1175 if (!(p.i_flags&GRE_KEY)) 1176 p.i_key = 0; 1177 if (!(p.o_flags&GRE_KEY)) 1178 p.o_key = 0; 1179 1180 ip6gre_tnl_parm_from_user(&p1, &p); 1181 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1182 1183 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1184 if (t != NULL) { 1185 if (t->dev != dev) { 1186 err = -EEXIST; 1187 break; 1188 } 1189 } else { 1190 t = netdev_priv(dev); 1191 1192 ip6gre_tunnel_unlink(ign, t); 1193 synchronize_net(); 1194 ip6gre_tnl_change(t, &p1, 1); 1195 ip6gre_tunnel_link(ign, t); 1196 netdev_state_change(dev); 1197 } 1198 } 1199 1200 if (t) { 1201 err = 0; 1202 1203 ip6gre_tnl_parm_to_user(&p, &t->parms); 1204 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1205 err = -EFAULT; 1206 } else 1207 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1208 break; 1209 1210 case SIOCDELTUNNEL: 1211 err = -EPERM; 1212 if (!capable(CAP_NET_ADMIN)) 1213 goto done; 1214 1215 if (dev == ign->fb_tunnel_dev) { 1216 err = -EFAULT; 1217 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1218 goto done; 1219 err = -ENOENT; 1220 ip6gre_tnl_parm_from_user(&p1, &p); 1221 t = ip6gre_tunnel_locate(net, &p1, 0); 1222 if (t == NULL) 1223 goto done; 1224 err = -EPERM; 1225 if (t == netdev_priv(ign->fb_tunnel_dev)) 1226 goto done; 1227 dev = t->dev; 1228 } 1229 unregister_netdevice(dev); 1230 err = 0; 1231 break; 1232 1233 default: 1234 err = -EINVAL; 1235 } 1236 1237 done: 1238 return err; 1239 } 1240 1241 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1242 { 1243 struct ip6_tnl *tunnel = netdev_priv(dev); 1244 if (new_mtu < 68 || 1245 new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen) 1246 return -EINVAL; 1247 dev->mtu = new_mtu; 1248 return 0; 1249 } 1250 1251 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1252 unsigned short type, 1253 const void *daddr, const void *saddr, unsigned int len) 1254 { 1255 struct ip6_tnl *t = netdev_priv(dev); 1256 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1257 __be16 *p = (__be16 *)(ipv6h+1); 1258 1259 *(__be32 *)ipv6h = t->fl.u.ip6.flowlabel | htonl(0x60000000); 1260 ipv6h->hop_limit = t->parms.hop_limit; 1261 ipv6h->nexthdr = NEXTHDR_GRE; 1262 ipv6h->saddr = t->parms.laddr; 1263 ipv6h->daddr = t->parms.raddr; 1264 1265 p[0] = t->parms.o_flags; 1266 p[1] = htons(type); 1267 1268 /* 1269 * Set the source hardware address. 1270 */ 1271 1272 if (saddr) 1273 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1274 if (daddr) 1275 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1276 if (!ipv6_addr_any(&ipv6h->daddr)) 1277 return t->hlen; 1278 1279 return -t->hlen; 1280 } 1281 1282 static const struct header_ops ip6gre_header_ops = { 1283 .create = ip6gre_header, 1284 }; 1285 1286 static const struct net_device_ops ip6gre_netdev_ops = { 1287 .ndo_init = ip6gre_tunnel_init, 1288 .ndo_uninit = ip6gre_tunnel_uninit, 1289 .ndo_start_xmit = ip6gre_tunnel_xmit, 1290 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1291 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1292 .ndo_get_stats64 = ip6gre_get_stats64, 1293 }; 1294 1295 static void ip6gre_dev_free(struct net_device *dev) 1296 { 1297 free_percpu(dev->tstats); 1298 free_netdev(dev); 1299 } 1300 1301 static void ip6gre_tunnel_setup(struct net_device *dev) 1302 { 1303 struct ip6_tnl *t; 1304 1305 dev->netdev_ops = &ip6gre_netdev_ops; 1306 dev->destructor = ip6gre_dev_free; 1307 1308 dev->type = ARPHRD_IP6GRE; 1309 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1310 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1311 t = netdev_priv(dev); 1312 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1313 dev->mtu -= 8; 1314 dev->flags |= IFF_NOARP; 1315 dev->iflink = 0; 1316 dev->addr_len = sizeof(struct in6_addr); 1317 dev->features |= NETIF_F_NETNS_LOCAL; 1318 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1319 } 1320 1321 static int ip6gre_tunnel_init(struct net_device *dev) 1322 { 1323 struct ip6_tnl *tunnel; 1324 1325 tunnel = netdev_priv(dev); 1326 1327 tunnel->dev = dev; 1328 strcpy(tunnel->parms.name, dev->name); 1329 1330 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1331 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1332 1333 if (ipv6_addr_any(&tunnel->parms.raddr)) 1334 dev->header_ops = &ip6gre_header_ops; 1335 1336 dev->tstats = alloc_percpu(struct pcpu_tstats); 1337 if (!dev->tstats) 1338 return -ENOMEM; 1339 1340 return 0; 1341 } 1342 1343 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1344 { 1345 struct ip6_tnl *tunnel = netdev_priv(dev); 1346 1347 tunnel->dev = dev; 1348 strcpy(tunnel->parms.name, dev->name); 1349 1350 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1351 1352 dev_hold(dev); 1353 } 1354 1355 1356 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1357 .handler = ip6gre_rcv, 1358 .err_handler = ip6gre_err, 1359 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1360 }; 1361 1362 static void ip6gre_destroy_tunnels(struct ip6gre_net *ign, 1363 struct list_head *head) 1364 { 1365 int prio; 1366 1367 for (prio = 0; prio < 4; prio++) { 1368 int h; 1369 for (h = 0; h < HASH_SIZE; h++) { 1370 struct ip6_tnl *t; 1371 1372 t = rtnl_dereference(ign->tunnels[prio][h]); 1373 1374 while (t != NULL) { 1375 unregister_netdevice_queue(t->dev, head); 1376 t = rtnl_dereference(t->next); 1377 } 1378 } 1379 } 1380 } 1381 1382 static int __net_init ip6gre_init_net(struct net *net) 1383 { 1384 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1385 int err; 1386 1387 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1388 ip6gre_tunnel_setup); 1389 if (!ign->fb_tunnel_dev) { 1390 err = -ENOMEM; 1391 goto err_alloc_dev; 1392 } 1393 dev_net_set(ign->fb_tunnel_dev, net); 1394 1395 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1396 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1397 1398 err = register_netdev(ign->fb_tunnel_dev); 1399 if (err) 1400 goto err_reg_dev; 1401 1402 rcu_assign_pointer(ign->tunnels_wc[0], 1403 netdev_priv(ign->fb_tunnel_dev)); 1404 return 0; 1405 1406 err_reg_dev: 1407 ip6gre_dev_free(ign->fb_tunnel_dev); 1408 err_alloc_dev: 1409 return err; 1410 } 1411 1412 static void __net_exit ip6gre_exit_net(struct net *net) 1413 { 1414 struct ip6gre_net *ign; 1415 LIST_HEAD(list); 1416 1417 ign = net_generic(net, ip6gre_net_id); 1418 rtnl_lock(); 1419 ip6gre_destroy_tunnels(ign, &list); 1420 unregister_netdevice_many(&list); 1421 rtnl_unlock(); 1422 } 1423 1424 static struct pernet_operations ip6gre_net_ops = { 1425 .init = ip6gre_init_net, 1426 .exit = ip6gre_exit_net, 1427 .id = &ip6gre_net_id, 1428 .size = sizeof(struct ip6gre_net), 1429 }; 1430 1431 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1432 { 1433 __be16 flags; 1434 1435 if (!data) 1436 return 0; 1437 1438 flags = 0; 1439 if (data[IFLA_GRE_IFLAGS]) 1440 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1441 if (data[IFLA_GRE_OFLAGS]) 1442 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1443 if (flags & (GRE_VERSION|GRE_ROUTING)) 1444 return -EINVAL; 1445 1446 return 0; 1447 } 1448 1449 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1450 { 1451 struct in6_addr daddr; 1452 1453 if (tb[IFLA_ADDRESS]) { 1454 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1455 return -EINVAL; 1456 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1457 return -EADDRNOTAVAIL; 1458 } 1459 1460 if (!data) 1461 goto out; 1462 1463 if (data[IFLA_GRE_REMOTE]) { 1464 nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1465 if (ipv6_addr_any(&daddr)) 1466 return -EINVAL; 1467 } 1468 1469 out: 1470 return ip6gre_tunnel_validate(tb, data); 1471 } 1472 1473 1474 static void ip6gre_netlink_parms(struct nlattr *data[], 1475 struct __ip6_tnl_parm *parms) 1476 { 1477 memset(parms, 0, sizeof(*parms)); 1478 1479 if (!data) 1480 return; 1481 1482 if (data[IFLA_GRE_LINK]) 1483 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1484 1485 if (data[IFLA_GRE_IFLAGS]) 1486 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1487 1488 if (data[IFLA_GRE_OFLAGS]) 1489 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1490 1491 if (data[IFLA_GRE_IKEY]) 1492 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1493 1494 if (data[IFLA_GRE_OKEY]) 1495 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1496 1497 if (data[IFLA_GRE_LOCAL]) 1498 nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr)); 1499 1500 if (data[IFLA_GRE_REMOTE]) 1501 nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1502 1503 if (data[IFLA_GRE_TTL]) 1504 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1505 1506 if (data[IFLA_GRE_ENCAP_LIMIT]) 1507 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1508 1509 if (data[IFLA_GRE_FLOWINFO]) 1510 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1511 1512 if (data[IFLA_GRE_FLAGS]) 1513 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1514 } 1515 1516 static int ip6gre_tap_init(struct net_device *dev) 1517 { 1518 struct ip6_tnl *tunnel; 1519 1520 tunnel = netdev_priv(dev); 1521 1522 tunnel->dev = dev; 1523 strcpy(tunnel->parms.name, dev->name); 1524 1525 ip6gre_tnl_link_config(tunnel, 1); 1526 1527 dev->tstats = alloc_percpu(struct pcpu_tstats); 1528 if (!dev->tstats) 1529 return -ENOMEM; 1530 1531 return 0; 1532 } 1533 1534 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1535 .ndo_init = ip6gre_tap_init, 1536 .ndo_uninit = ip6gre_tunnel_uninit, 1537 .ndo_start_xmit = ip6gre_tunnel_xmit, 1538 .ndo_set_mac_address = eth_mac_addr, 1539 .ndo_validate_addr = eth_validate_addr, 1540 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1541 .ndo_get_stats64 = ip6gre_get_stats64, 1542 }; 1543 1544 static void ip6gre_tap_setup(struct net_device *dev) 1545 { 1546 1547 ether_setup(dev); 1548 1549 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1550 dev->destructor = ip6gre_dev_free; 1551 1552 dev->iflink = 0; 1553 dev->features |= NETIF_F_NETNS_LOCAL; 1554 } 1555 1556 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1557 struct nlattr *tb[], struct nlattr *data[]) 1558 { 1559 struct ip6_tnl *nt; 1560 struct net *net = dev_net(dev); 1561 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1562 int err; 1563 1564 nt = netdev_priv(dev); 1565 ip6gre_netlink_parms(data, &nt->parms); 1566 1567 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1568 return -EEXIST; 1569 1570 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1571 eth_hw_addr_random(dev); 1572 1573 nt->dev = dev; 1574 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1575 1576 /* Can use a lockless transmit, unless we generate output sequences */ 1577 if (!(nt->parms.o_flags & GRE_SEQ)) 1578 dev->features |= NETIF_F_LLTX; 1579 1580 err = register_netdevice(dev); 1581 if (err) 1582 goto out; 1583 1584 dev_hold(dev); 1585 ip6gre_tunnel_link(ign, nt); 1586 1587 out: 1588 return err; 1589 } 1590 1591 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1592 struct nlattr *data[]) 1593 { 1594 struct ip6_tnl *t, *nt; 1595 struct net *net = dev_net(dev); 1596 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1597 struct __ip6_tnl_parm p; 1598 1599 if (dev == ign->fb_tunnel_dev) 1600 return -EINVAL; 1601 1602 nt = netdev_priv(dev); 1603 ip6gre_netlink_parms(data, &p); 1604 1605 t = ip6gre_tunnel_locate(net, &p, 0); 1606 1607 if (t) { 1608 if (t->dev != dev) 1609 return -EEXIST; 1610 } else { 1611 t = nt; 1612 1613 ip6gre_tunnel_unlink(ign, t); 1614 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1615 ip6gre_tunnel_link(ign, t); 1616 netdev_state_change(dev); 1617 } 1618 1619 return 0; 1620 } 1621 1622 static size_t ip6gre_get_size(const struct net_device *dev) 1623 { 1624 return 1625 /* IFLA_GRE_LINK */ 1626 nla_total_size(4) + 1627 /* IFLA_GRE_IFLAGS */ 1628 nla_total_size(2) + 1629 /* IFLA_GRE_OFLAGS */ 1630 nla_total_size(2) + 1631 /* IFLA_GRE_IKEY */ 1632 nla_total_size(4) + 1633 /* IFLA_GRE_OKEY */ 1634 nla_total_size(4) + 1635 /* IFLA_GRE_LOCAL */ 1636 nla_total_size(sizeof(struct in6_addr)) + 1637 /* IFLA_GRE_REMOTE */ 1638 nla_total_size(sizeof(struct in6_addr)) + 1639 /* IFLA_GRE_TTL */ 1640 nla_total_size(1) + 1641 /* IFLA_GRE_TOS */ 1642 nla_total_size(1) + 1643 /* IFLA_GRE_ENCAP_LIMIT */ 1644 nla_total_size(1) + 1645 /* IFLA_GRE_FLOWINFO */ 1646 nla_total_size(4) + 1647 /* IFLA_GRE_FLAGS */ 1648 nla_total_size(4) + 1649 0; 1650 } 1651 1652 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1653 { 1654 struct ip6_tnl *t = netdev_priv(dev); 1655 struct __ip6_tnl_parm *p = &t->parms; 1656 1657 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1658 nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) || 1659 nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) || 1660 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1661 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1662 nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->laddr) || 1663 nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->raddr) || 1664 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1665 /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/ 1666 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1667 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1668 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags)) 1669 goto nla_put_failure; 1670 return 0; 1671 1672 nla_put_failure: 1673 return -EMSGSIZE; 1674 } 1675 1676 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1677 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1678 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1679 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1680 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1681 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1682 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1683 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1684 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1685 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1686 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1687 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1688 }; 1689 1690 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1691 .kind = "ip6gre", 1692 .maxtype = IFLA_GRE_MAX, 1693 .policy = ip6gre_policy, 1694 .priv_size = sizeof(struct ip6_tnl), 1695 .setup = ip6gre_tunnel_setup, 1696 .validate = ip6gre_tunnel_validate, 1697 .newlink = ip6gre_newlink, 1698 .changelink = ip6gre_changelink, 1699 .get_size = ip6gre_get_size, 1700 .fill_info = ip6gre_fill_info, 1701 }; 1702 1703 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1704 .kind = "ip6gretap", 1705 .maxtype = IFLA_GRE_MAX, 1706 .policy = ip6gre_policy, 1707 .priv_size = sizeof(struct ip6_tnl), 1708 .setup = ip6gre_tap_setup, 1709 .validate = ip6gre_tap_validate, 1710 .newlink = ip6gre_newlink, 1711 .changelink = ip6gre_changelink, 1712 .get_size = ip6gre_get_size, 1713 .fill_info = ip6gre_fill_info, 1714 }; 1715 1716 /* 1717 * And now the modules code and kernel interface. 1718 */ 1719 1720 static int __init ip6gre_init(void) 1721 { 1722 int err; 1723 1724 pr_info("GRE over IPv6 tunneling driver\n"); 1725 1726 err = register_pernet_device(&ip6gre_net_ops); 1727 if (err < 0) 1728 return err; 1729 1730 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1731 if (err < 0) { 1732 pr_info("%s: can't add protocol\n", __func__); 1733 goto add_proto_failed; 1734 } 1735 1736 err = rtnl_link_register(&ip6gre_link_ops); 1737 if (err < 0) 1738 goto rtnl_link_failed; 1739 1740 err = rtnl_link_register(&ip6gre_tap_ops); 1741 if (err < 0) 1742 goto tap_ops_failed; 1743 1744 out: 1745 return err; 1746 1747 tap_ops_failed: 1748 rtnl_link_unregister(&ip6gre_link_ops); 1749 rtnl_link_failed: 1750 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1751 add_proto_failed: 1752 unregister_pernet_device(&ip6gre_net_ops); 1753 goto out; 1754 } 1755 1756 static void __exit ip6gre_fini(void) 1757 { 1758 rtnl_link_unregister(&ip6gre_tap_ops); 1759 rtnl_link_unregister(&ip6gre_link_ops); 1760 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1761 unregister_pernet_device(&ip6gre_net_ops); 1762 } 1763 1764 module_init(ip6gre_init); 1765 module_exit(ip6gre_fini); 1766 MODULE_LICENSE("GPL"); 1767 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1768 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1769 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1770 MODULE_ALIAS_NETDEV("ip6gre0"); 1771