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 static struct rtnl_link_stats64 *ip6gre_get_stats64(struct net_device *dev, 114 struct rtnl_link_stats64 *tot) 115 { 116 int i; 117 118 for_each_possible_cpu(i) { 119 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i); 120 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 121 unsigned int start; 122 123 do { 124 start = u64_stats_fetch_begin_bh(&tstats->syncp); 125 rx_packets = tstats->rx_packets; 126 tx_packets = tstats->tx_packets; 127 rx_bytes = tstats->rx_bytes; 128 tx_bytes = tstats->tx_bytes; 129 } while (u64_stats_fetch_retry_bh(&tstats->syncp, start)); 130 131 tot->rx_packets += rx_packets; 132 tot->tx_packets += tx_packets; 133 tot->rx_bytes += rx_bytes; 134 tot->tx_bytes += tx_bytes; 135 } 136 137 tot->multicast = dev->stats.multicast; 138 tot->rx_crc_errors = dev->stats.rx_crc_errors; 139 tot->rx_fifo_errors = dev->stats.rx_fifo_errors; 140 tot->rx_length_errors = dev->stats.rx_length_errors; 141 tot->rx_frame_errors = dev->stats.rx_frame_errors; 142 tot->rx_errors = dev->stats.rx_errors; 143 144 tot->tx_fifo_errors = dev->stats.tx_fifo_errors; 145 tot->tx_carrier_errors = dev->stats.tx_carrier_errors; 146 tot->tx_dropped = dev->stats.tx_dropped; 147 tot->tx_aborted_errors = dev->stats.tx_aborted_errors; 148 tot->tx_errors = dev->stats.tx_errors; 149 150 return tot; 151 } 152 153 /* Given src, dst and key, find appropriate for input tunnel. */ 154 155 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev, 156 const struct in6_addr *remote, const struct in6_addr *local, 157 __be32 key, __be16 gre_proto) 158 { 159 struct net *net = dev_net(dev); 160 int link = dev->ifindex; 161 unsigned int h0 = HASH_ADDR(remote); 162 unsigned int h1 = HASH_KEY(key); 163 struct ip6_tnl *t, *cand = NULL; 164 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 165 int dev_type = (gre_proto == htons(ETH_P_TEB)) ? 166 ARPHRD_ETHER : ARPHRD_IP6GRE; 167 int score, cand_score = 4; 168 169 for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) { 170 if (!ipv6_addr_equal(local, &t->parms.laddr) || 171 !ipv6_addr_equal(remote, &t->parms.raddr) || 172 key != t->parms.i_key || 173 !(t->dev->flags & IFF_UP)) 174 continue; 175 176 if (t->dev->type != ARPHRD_IP6GRE && 177 t->dev->type != dev_type) 178 continue; 179 180 score = 0; 181 if (t->parms.link != link) 182 score |= 1; 183 if (t->dev->type != dev_type) 184 score |= 2; 185 if (score == 0) 186 return t; 187 188 if (score < cand_score) { 189 cand = t; 190 cand_score = score; 191 } 192 } 193 194 for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) { 195 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 196 key != t->parms.i_key || 197 !(t->dev->flags & IFF_UP)) 198 continue; 199 200 if (t->dev->type != ARPHRD_IP6GRE && 201 t->dev->type != dev_type) 202 continue; 203 204 score = 0; 205 if (t->parms.link != link) 206 score |= 1; 207 if (t->dev->type != dev_type) 208 score |= 2; 209 if (score == 0) 210 return t; 211 212 if (score < cand_score) { 213 cand = t; 214 cand_score = score; 215 } 216 } 217 218 for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) { 219 if ((!ipv6_addr_equal(local, &t->parms.laddr) && 220 (!ipv6_addr_equal(local, &t->parms.raddr) || 221 !ipv6_addr_is_multicast(local))) || 222 key != t->parms.i_key || 223 !(t->dev->flags & IFF_UP)) 224 continue; 225 226 if (t->dev->type != ARPHRD_IP6GRE && 227 t->dev->type != dev_type) 228 continue; 229 230 score = 0; 231 if (t->parms.link != link) 232 score |= 1; 233 if (t->dev->type != dev_type) 234 score |= 2; 235 if (score == 0) 236 return t; 237 238 if (score < cand_score) { 239 cand = t; 240 cand_score = score; 241 } 242 } 243 244 for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) { 245 if (t->parms.i_key != key || 246 !(t->dev->flags & IFF_UP)) 247 continue; 248 249 if (t->dev->type != ARPHRD_IP6GRE && 250 t->dev->type != dev_type) 251 continue; 252 253 score = 0; 254 if (t->parms.link != link) 255 score |= 1; 256 if (t->dev->type != dev_type) 257 score |= 2; 258 if (score == 0) 259 return t; 260 261 if (score < cand_score) { 262 cand = t; 263 cand_score = score; 264 } 265 } 266 267 if (cand != NULL) 268 return cand; 269 270 dev = ign->fb_tunnel_dev; 271 if (dev->flags & IFF_UP) 272 return netdev_priv(dev); 273 274 return NULL; 275 } 276 277 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign, 278 const struct __ip6_tnl_parm *p) 279 { 280 const struct in6_addr *remote = &p->raddr; 281 const struct in6_addr *local = &p->laddr; 282 unsigned int h = HASH_KEY(p->i_key); 283 int prio = 0; 284 285 if (!ipv6_addr_any(local)) 286 prio |= 1; 287 if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) { 288 prio |= 2; 289 h ^= HASH_ADDR(remote); 290 } 291 292 return &ign->tunnels[prio][h]; 293 } 294 295 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign, 296 const struct ip6_tnl *t) 297 { 298 return __ip6gre_bucket(ign, &t->parms); 299 } 300 301 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t) 302 { 303 struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t); 304 305 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 306 rcu_assign_pointer(*tp, t); 307 } 308 309 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t) 310 { 311 struct ip6_tnl __rcu **tp; 312 struct ip6_tnl *iter; 313 314 for (tp = ip6gre_bucket(ign, t); 315 (iter = rtnl_dereference(*tp)) != NULL; 316 tp = &iter->next) { 317 if (t == iter) { 318 rcu_assign_pointer(*tp, t->next); 319 break; 320 } 321 } 322 } 323 324 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net, 325 const struct __ip6_tnl_parm *parms, 326 int type) 327 { 328 const struct in6_addr *remote = &parms->raddr; 329 const struct in6_addr *local = &parms->laddr; 330 __be32 key = parms->i_key; 331 int link = parms->link; 332 struct ip6_tnl *t; 333 struct ip6_tnl __rcu **tp; 334 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 335 336 for (tp = __ip6gre_bucket(ign, parms); 337 (t = rtnl_dereference(*tp)) != NULL; 338 tp = &t->next) 339 if (ipv6_addr_equal(local, &t->parms.laddr) && 340 ipv6_addr_equal(remote, &t->parms.raddr) && 341 key == t->parms.i_key && 342 link == t->parms.link && 343 type == t->dev->type) 344 break; 345 346 return t; 347 } 348 349 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, 350 const struct __ip6_tnl_parm *parms, int create) 351 { 352 struct ip6_tnl *t, *nt; 353 struct net_device *dev; 354 char name[IFNAMSIZ]; 355 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 356 357 t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE); 358 if (t || !create) 359 return t; 360 361 if (parms->name[0]) 362 strlcpy(name, parms->name, IFNAMSIZ); 363 else 364 strcpy(name, "ip6gre%d"); 365 366 dev = alloc_netdev(sizeof(*t), name, ip6gre_tunnel_setup); 367 if (!dev) 368 return NULL; 369 370 dev_net_set(dev, net); 371 372 nt = netdev_priv(dev); 373 nt->parms = *parms; 374 dev->rtnl_link_ops = &ip6gre_link_ops; 375 376 nt->dev = dev; 377 ip6gre_tnl_link_config(nt, 1); 378 379 if (register_netdevice(dev) < 0) 380 goto failed_free; 381 382 /* Can use a lockless transmit, unless we generate output sequences */ 383 if (!(nt->parms.o_flags & GRE_SEQ)) 384 dev->features |= NETIF_F_LLTX; 385 386 dev_hold(dev); 387 ip6gre_tunnel_link(ign, nt); 388 return nt; 389 390 failed_free: 391 free_netdev(dev); 392 return NULL; 393 } 394 395 static void ip6gre_tunnel_uninit(struct net_device *dev) 396 { 397 struct net *net = dev_net(dev); 398 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 399 400 ip6gre_tunnel_unlink(ign, netdev_priv(dev)); 401 dev_put(dev); 402 } 403 404 405 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 406 u8 type, u8 code, int offset, __be32 info) 407 { 408 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 409 __be16 *p = (__be16 *)(skb->data + offset); 410 int grehlen = offset + 4; 411 struct ip6_tnl *t; 412 __be16 flags; 413 414 flags = p[0]; 415 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 416 if (flags&(GRE_VERSION|GRE_ROUTING)) 417 return; 418 if (flags&GRE_KEY) { 419 grehlen += 4; 420 if (flags&GRE_CSUM) 421 grehlen += 4; 422 } 423 } 424 425 /* If only 8 bytes returned, keyed message will be dropped here */ 426 if (!pskb_may_pull(skb, grehlen)) 427 return; 428 ipv6h = (const struct ipv6hdr *)skb->data; 429 p = (__be16 *)(skb->data + offset); 430 431 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 432 flags & GRE_KEY ? 433 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 434 p[1]); 435 if (t == NULL) 436 return; 437 438 switch (type) { 439 __u32 teli; 440 struct ipv6_tlv_tnl_enc_lim *tel; 441 __u32 mtu; 442 case ICMPV6_DEST_UNREACH: 443 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n", 444 t->parms.name); 445 break; 446 case ICMPV6_TIME_EXCEED: 447 if (code == ICMPV6_EXC_HOPLIMIT) { 448 net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 449 t->parms.name); 450 } 451 break; 452 case ICMPV6_PARAMPROB: 453 teli = 0; 454 if (code == ICMPV6_HDR_FIELD) 455 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 456 457 if (teli && teli == info - 2) { 458 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 459 if (tel->encap_limit == 0) { 460 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 461 t->parms.name); 462 } 463 } else { 464 net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 465 t->parms.name); 466 } 467 break; 468 case ICMPV6_PKT_TOOBIG: 469 mtu = info - offset; 470 if (mtu < IPV6_MIN_MTU) 471 mtu = IPV6_MIN_MTU; 472 t->dev->mtu = mtu; 473 break; 474 } 475 476 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 477 t->err_count++; 478 else 479 t->err_count = 1; 480 t->err_time = jiffies; 481 } 482 483 static int ip6gre_rcv(struct sk_buff *skb) 484 { 485 const struct ipv6hdr *ipv6h; 486 u8 *h; 487 __be16 flags; 488 __sum16 csum = 0; 489 __be32 key = 0; 490 u32 seqno = 0; 491 struct ip6_tnl *tunnel; 492 int offset = 4; 493 __be16 gre_proto; 494 int err; 495 496 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 497 goto drop; 498 499 ipv6h = ipv6_hdr(skb); 500 h = skb->data; 501 flags = *(__be16 *)h; 502 503 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 504 /* - Version must be 0. 505 - We do not support routing headers. 506 */ 507 if (flags&(GRE_VERSION|GRE_ROUTING)) 508 goto drop; 509 510 if (flags&GRE_CSUM) { 511 switch (skb->ip_summed) { 512 case CHECKSUM_COMPLETE: 513 csum = csum_fold(skb->csum); 514 if (!csum) 515 break; 516 /* fall through */ 517 case CHECKSUM_NONE: 518 skb->csum = 0; 519 csum = __skb_checksum_complete(skb); 520 skb->ip_summed = CHECKSUM_COMPLETE; 521 } 522 offset += 4; 523 } 524 if (flags&GRE_KEY) { 525 key = *(__be32 *)(h + offset); 526 offset += 4; 527 } 528 if (flags&GRE_SEQ) { 529 seqno = ntohl(*(__be32 *)(h + offset)); 530 offset += 4; 531 } 532 } 533 534 gre_proto = *(__be16 *)(h + 2); 535 536 tunnel = ip6gre_tunnel_lookup(skb->dev, 537 &ipv6h->saddr, &ipv6h->daddr, key, 538 gre_proto); 539 if (tunnel) { 540 struct pcpu_tstats *tstats; 541 542 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 543 goto drop; 544 545 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 546 tunnel->dev->stats.rx_dropped++; 547 goto drop; 548 } 549 550 secpath_reset(skb); 551 552 skb->protocol = gre_proto; 553 /* WCCP version 1 and 2 protocol decoding. 554 * - Change protocol to IP 555 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 556 */ 557 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 558 skb->protocol = htons(ETH_P_IP); 559 if ((*(h + offset) & 0xF0) != 0x40) 560 offset += 4; 561 } 562 563 skb->mac_header = skb->network_header; 564 __pskb_pull(skb, offset); 565 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 566 skb->pkt_type = PACKET_HOST; 567 568 if (((flags&GRE_CSUM) && csum) || 569 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 570 tunnel->dev->stats.rx_crc_errors++; 571 tunnel->dev->stats.rx_errors++; 572 goto drop; 573 } 574 if (tunnel->parms.i_flags&GRE_SEQ) { 575 if (!(flags&GRE_SEQ) || 576 (tunnel->i_seqno && 577 (s32)(seqno - tunnel->i_seqno) < 0)) { 578 tunnel->dev->stats.rx_fifo_errors++; 579 tunnel->dev->stats.rx_errors++; 580 goto drop; 581 } 582 tunnel->i_seqno = seqno + 1; 583 } 584 585 /* Warning: All skb pointers will be invalidated! */ 586 if (tunnel->dev->type == ARPHRD_ETHER) { 587 if (!pskb_may_pull(skb, ETH_HLEN)) { 588 tunnel->dev->stats.rx_length_errors++; 589 tunnel->dev->stats.rx_errors++; 590 goto drop; 591 } 592 593 ipv6h = ipv6_hdr(skb); 594 skb->protocol = eth_type_trans(skb, tunnel->dev); 595 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 596 } 597 598 __skb_tunnel_rx(skb, tunnel->dev); 599 600 skb_reset_network_header(skb); 601 602 err = IP6_ECN_decapsulate(ipv6h, skb); 603 if (unlikely(err)) { 604 if (log_ecn_error) 605 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 606 &ipv6h->saddr, 607 ipv6_get_dsfield(ipv6h)); 608 if (err > 1) { 609 ++tunnel->dev->stats.rx_frame_errors; 610 ++tunnel->dev->stats.rx_errors; 611 goto drop; 612 } 613 } 614 615 tstats = this_cpu_ptr(tunnel->dev->tstats); 616 u64_stats_update_begin(&tstats->syncp); 617 tstats->rx_packets++; 618 tstats->rx_bytes += skb->len; 619 u64_stats_update_end(&tstats->syncp); 620 621 netif_rx(skb); 622 623 return 0; 624 } 625 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 626 627 drop: 628 kfree_skb(skb); 629 return 0; 630 } 631 632 struct ipv6_tel_txoption { 633 struct ipv6_txoptions ops; 634 __u8 dst_opt[8]; 635 }; 636 637 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 638 { 639 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 640 641 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 642 opt->dst_opt[3] = 1; 643 opt->dst_opt[4] = encap_limit; 644 opt->dst_opt[5] = IPV6_TLV_PADN; 645 opt->dst_opt[6] = 1; 646 647 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 648 opt->ops.opt_nflen = 8; 649 } 650 651 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 652 struct net_device *dev, 653 __u8 dsfield, 654 struct flowi6 *fl6, 655 int encap_limit, 656 __u32 *pmtu) 657 { 658 struct net *net = dev_net(dev); 659 struct ip6_tnl *tunnel = netdev_priv(dev); 660 struct net_device *tdev; /* Device to other host */ 661 struct ipv6hdr *ipv6h; /* Our new IP header */ 662 unsigned int max_headroom; /* The extra header space needed */ 663 int gre_hlen; 664 struct ipv6_tel_txoption opt; 665 int mtu; 666 struct dst_entry *dst = NULL, *ndst = NULL; 667 struct net_device_stats *stats = &tunnel->dev->stats; 668 int err = -1; 669 u8 proto; 670 int pkt_len; 671 struct sk_buff *new_skb; 672 673 if (dev->type == ARPHRD_ETHER) 674 IPCB(skb)->flags = 0; 675 676 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 677 gre_hlen = 0; 678 ipv6h = (struct ipv6hdr *)skb->data; 679 fl6->daddr = ipv6h->daddr; 680 } else { 681 gre_hlen = tunnel->hlen; 682 fl6->daddr = tunnel->parms.raddr; 683 } 684 685 if (!fl6->flowi6_mark) 686 dst = ip6_tnl_dst_check(tunnel); 687 688 if (!dst) { 689 ndst = ip6_route_output(net, NULL, fl6); 690 691 if (ndst->error) 692 goto tx_err_link_failure; 693 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); 694 if (IS_ERR(ndst)) { 695 err = PTR_ERR(ndst); 696 ndst = NULL; 697 goto tx_err_link_failure; 698 } 699 dst = ndst; 700 } 701 702 tdev = dst->dev; 703 704 if (tdev == dev) { 705 stats->collisions++; 706 net_warn_ratelimited("%s: Local routing loop detected!\n", 707 tunnel->parms.name); 708 goto tx_err_dst_release; 709 } 710 711 mtu = dst_mtu(dst) - sizeof(*ipv6h); 712 if (encap_limit >= 0) { 713 max_headroom += 8; 714 mtu -= 8; 715 } 716 if (mtu < IPV6_MIN_MTU) 717 mtu = IPV6_MIN_MTU; 718 if (skb_dst(skb)) 719 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 720 if (skb->len > mtu) { 721 *pmtu = mtu; 722 err = -EMSGSIZE; 723 goto tx_err_dst_release; 724 } 725 726 if (tunnel->err_count > 0) { 727 if (time_before(jiffies, 728 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 729 tunnel->err_count--; 730 731 dst_link_failure(skb); 732 } else 733 tunnel->err_count = 0; 734 } 735 736 max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; 737 738 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 739 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 740 new_skb = skb_realloc_headroom(skb, max_headroom); 741 if (max_headroom > dev->needed_headroom) 742 dev->needed_headroom = max_headroom; 743 if (!new_skb) 744 goto tx_err_dst_release; 745 746 if (skb->sk) 747 skb_set_owner_w(new_skb, skb->sk); 748 consume_skb(skb); 749 skb = new_skb; 750 } 751 752 skb_dst_drop(skb); 753 754 if (fl6->flowi6_mark) { 755 skb_dst_set(skb, dst); 756 ndst = NULL; 757 } else { 758 skb_dst_set_noref(skb, dst); 759 } 760 761 proto = NEXTHDR_GRE; 762 if (encap_limit >= 0) { 763 init_tel_txopt(&opt, encap_limit); 764 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 765 } 766 767 skb_push(skb, gre_hlen); 768 skb_reset_network_header(skb); 769 skb_set_transport_header(skb, sizeof(*ipv6h)); 770 771 /* 772 * Push down and install the IP header. 773 */ 774 ipv6h = ipv6_hdr(skb); 775 *(__be32 *)ipv6h = fl6->flowlabel | htonl(0x60000000); 776 dsfield = INET_ECN_encapsulate(0, dsfield); 777 ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield); 778 ipv6h->hop_limit = tunnel->parms.hop_limit; 779 ipv6h->nexthdr = proto; 780 ipv6h->saddr = fl6->saddr; 781 ipv6h->daddr = fl6->daddr; 782 783 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 784 ((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ? 785 htons(ETH_P_TEB) : skb->protocol; 786 787 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 788 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 789 790 if (tunnel->parms.o_flags&GRE_SEQ) { 791 ++tunnel->o_seqno; 792 *ptr = htonl(tunnel->o_seqno); 793 ptr--; 794 } 795 if (tunnel->parms.o_flags&GRE_KEY) { 796 *ptr = tunnel->parms.o_key; 797 ptr--; 798 } 799 if (tunnel->parms.o_flags&GRE_CSUM) { 800 *ptr = 0; 801 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 802 skb->len - sizeof(struct ipv6hdr)); 803 } 804 } 805 806 nf_reset(skb); 807 pkt_len = skb->len; 808 err = ip6_local_out(skb); 809 810 if (net_xmit_eval(err) == 0) { 811 struct pcpu_tstats *tstats = this_cpu_ptr(tunnel->dev->tstats); 812 813 tstats->tx_bytes += pkt_len; 814 tstats->tx_packets++; 815 } else { 816 stats->tx_errors++; 817 stats->tx_aborted_errors++; 818 } 819 820 if (ndst) 821 ip6_tnl_dst_store(tunnel, ndst); 822 823 return 0; 824 tx_err_link_failure: 825 stats->tx_carrier_errors++; 826 dst_link_failure(skb); 827 tx_err_dst_release: 828 dst_release(ndst); 829 return err; 830 } 831 832 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 833 { 834 struct ip6_tnl *t = netdev_priv(dev); 835 const struct iphdr *iph = ip_hdr(skb); 836 int encap_limit = -1; 837 struct flowi6 fl6; 838 __u8 dsfield; 839 __u32 mtu; 840 int err; 841 842 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 843 encap_limit = t->parms.encap_limit; 844 845 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 846 fl6.flowi6_proto = IPPROTO_IPIP; 847 848 dsfield = ipv4_get_dsfield(iph); 849 850 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 851 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 852 & IPV6_TCLASS_MASK; 853 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 854 fl6.flowi6_mark = skb->mark; 855 856 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 857 if (err != 0) { 858 /* XXX: send ICMP error even if DF is not set. */ 859 if (err == -EMSGSIZE) 860 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 861 htonl(mtu)); 862 return -1; 863 } 864 865 return 0; 866 } 867 868 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 869 { 870 struct ip6_tnl *t = netdev_priv(dev); 871 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 872 int encap_limit = -1; 873 __u16 offset; 874 struct flowi6 fl6; 875 __u8 dsfield; 876 __u32 mtu; 877 int err; 878 879 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 880 return -1; 881 882 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 883 if (offset > 0) { 884 struct ipv6_tlv_tnl_enc_lim *tel; 885 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 886 if (tel->encap_limit == 0) { 887 icmpv6_send(skb, ICMPV6_PARAMPROB, 888 ICMPV6_HDR_FIELD, offset + 2); 889 return -1; 890 } 891 encap_limit = tel->encap_limit - 1; 892 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 893 encap_limit = t->parms.encap_limit; 894 895 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 896 fl6.flowi6_proto = IPPROTO_IPV6; 897 898 dsfield = ipv6_get_dsfield(ipv6h); 899 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 900 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 901 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 902 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); 903 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 904 fl6.flowi6_mark = skb->mark; 905 906 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 907 if (err != 0) { 908 if (err == -EMSGSIZE) 909 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 910 return -1; 911 } 912 913 return 0; 914 } 915 916 /** 917 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 918 * @t: the outgoing tunnel device 919 * @hdr: IPv6 header from the incoming packet 920 * 921 * Description: 922 * Avoid trivial tunneling loop by checking that tunnel exit-point 923 * doesn't match source of incoming packet. 924 * 925 * Return: 926 * 1 if conflict, 927 * 0 else 928 **/ 929 930 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 931 const struct ipv6hdr *hdr) 932 { 933 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 934 } 935 936 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 937 { 938 struct ip6_tnl *t = netdev_priv(dev); 939 int encap_limit = -1; 940 struct flowi6 fl6; 941 __u32 mtu; 942 int err; 943 944 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 945 encap_limit = t->parms.encap_limit; 946 947 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 948 fl6.flowi6_proto = skb->protocol; 949 950 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 951 952 return err; 953 } 954 955 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 956 struct net_device *dev) 957 { 958 struct ip6_tnl *t = netdev_priv(dev); 959 struct net_device_stats *stats = &t->dev->stats; 960 int ret; 961 962 if (!ip6_tnl_xmit_ctl(t)) 963 goto tx_err; 964 965 switch (skb->protocol) { 966 case htons(ETH_P_IP): 967 ret = ip6gre_xmit_ipv4(skb, dev); 968 break; 969 case htons(ETH_P_IPV6): 970 ret = ip6gre_xmit_ipv6(skb, dev); 971 break; 972 default: 973 ret = ip6gre_xmit_other(skb, dev); 974 break; 975 } 976 977 if (ret < 0) 978 goto tx_err; 979 980 return NETDEV_TX_OK; 981 982 tx_err: 983 stats->tx_errors++; 984 stats->tx_dropped++; 985 kfree_skb(skb); 986 return NETDEV_TX_OK; 987 } 988 989 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 990 { 991 struct net_device *dev = t->dev; 992 struct __ip6_tnl_parm *p = &t->parms; 993 struct flowi6 *fl6 = &t->fl.u.ip6; 994 int addend = sizeof(struct ipv6hdr) + 4; 995 996 if (dev->type != ARPHRD_ETHER) { 997 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 998 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 999 } 1000 1001 /* Set up flowi template */ 1002 fl6->saddr = p->laddr; 1003 fl6->daddr = p->raddr; 1004 fl6->flowi6_oif = p->link; 1005 fl6->flowlabel = 0; 1006 1007 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 1008 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 1009 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 1010 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 1011 1012 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 1013 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 1014 1015 if (p->flags&IP6_TNL_F_CAP_XMIT && 1016 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 1017 dev->flags |= IFF_POINTOPOINT; 1018 else 1019 dev->flags &= ~IFF_POINTOPOINT; 1020 1021 dev->iflink = p->link; 1022 1023 /* Precalculate GRE options length */ 1024 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 1025 if (t->parms.o_flags&GRE_CSUM) 1026 addend += 4; 1027 if (t->parms.o_flags&GRE_KEY) 1028 addend += 4; 1029 if (t->parms.o_flags&GRE_SEQ) 1030 addend += 4; 1031 } 1032 1033 if (p->flags & IP6_TNL_F_CAP_XMIT) { 1034 int strict = (ipv6_addr_type(&p->raddr) & 1035 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 1036 1037 struct rt6_info *rt = rt6_lookup(dev_net(dev), 1038 &p->raddr, &p->laddr, 1039 p->link, strict); 1040 1041 if (rt == NULL) 1042 return; 1043 1044 if (rt->dst.dev) { 1045 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 1046 1047 if (set_mtu) { 1048 dev->mtu = rt->dst.dev->mtu - addend; 1049 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1050 dev->mtu -= 8; 1051 1052 if (dev->mtu < IPV6_MIN_MTU) 1053 dev->mtu = IPV6_MIN_MTU; 1054 } 1055 } 1056 ip6_rt_put(rt); 1057 } 1058 1059 t->hlen = addend; 1060 } 1061 1062 static int ip6gre_tnl_change(struct ip6_tnl *t, 1063 const struct __ip6_tnl_parm *p, int set_mtu) 1064 { 1065 t->parms.laddr = p->laddr; 1066 t->parms.raddr = p->raddr; 1067 t->parms.flags = p->flags; 1068 t->parms.hop_limit = p->hop_limit; 1069 t->parms.encap_limit = p->encap_limit; 1070 t->parms.flowinfo = p->flowinfo; 1071 t->parms.link = p->link; 1072 t->parms.proto = p->proto; 1073 t->parms.i_key = p->i_key; 1074 t->parms.o_key = p->o_key; 1075 t->parms.i_flags = p->i_flags; 1076 t->parms.o_flags = p->o_flags; 1077 ip6_tnl_dst_reset(t); 1078 ip6gre_tnl_link_config(t, set_mtu); 1079 return 0; 1080 } 1081 1082 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1083 const struct ip6_tnl_parm2 *u) 1084 { 1085 p->laddr = u->laddr; 1086 p->raddr = u->raddr; 1087 p->flags = u->flags; 1088 p->hop_limit = u->hop_limit; 1089 p->encap_limit = u->encap_limit; 1090 p->flowinfo = u->flowinfo; 1091 p->link = u->link; 1092 p->i_key = u->i_key; 1093 p->o_key = u->o_key; 1094 p->i_flags = u->i_flags; 1095 p->o_flags = u->o_flags; 1096 memcpy(p->name, u->name, sizeof(u->name)); 1097 } 1098 1099 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1100 const struct __ip6_tnl_parm *p) 1101 { 1102 u->proto = IPPROTO_GRE; 1103 u->laddr = p->laddr; 1104 u->raddr = p->raddr; 1105 u->flags = p->flags; 1106 u->hop_limit = p->hop_limit; 1107 u->encap_limit = p->encap_limit; 1108 u->flowinfo = p->flowinfo; 1109 u->link = p->link; 1110 u->i_key = p->i_key; 1111 u->o_key = p->o_key; 1112 u->i_flags = p->i_flags; 1113 u->o_flags = p->o_flags; 1114 memcpy(u->name, p->name, sizeof(u->name)); 1115 } 1116 1117 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1118 struct ifreq *ifr, int cmd) 1119 { 1120 int err = 0; 1121 struct ip6_tnl_parm2 p; 1122 struct __ip6_tnl_parm p1; 1123 struct ip6_tnl *t; 1124 struct net *net = dev_net(dev); 1125 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1126 1127 switch (cmd) { 1128 case SIOCGETTUNNEL: 1129 t = NULL; 1130 if (dev == ign->fb_tunnel_dev) { 1131 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1132 err = -EFAULT; 1133 break; 1134 } 1135 ip6gre_tnl_parm_from_user(&p1, &p); 1136 t = ip6gre_tunnel_locate(net, &p1, 0); 1137 } 1138 if (t == NULL) 1139 t = netdev_priv(dev); 1140 ip6gre_tnl_parm_to_user(&p, &t->parms); 1141 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1142 err = -EFAULT; 1143 break; 1144 1145 case SIOCADDTUNNEL: 1146 case SIOCCHGTUNNEL: 1147 err = -EPERM; 1148 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1149 goto done; 1150 1151 err = -EFAULT; 1152 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1153 goto done; 1154 1155 err = -EINVAL; 1156 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1157 goto done; 1158 1159 if (!(p.i_flags&GRE_KEY)) 1160 p.i_key = 0; 1161 if (!(p.o_flags&GRE_KEY)) 1162 p.o_key = 0; 1163 1164 ip6gre_tnl_parm_from_user(&p1, &p); 1165 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1166 1167 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1168 if (t != NULL) { 1169 if (t->dev != dev) { 1170 err = -EEXIST; 1171 break; 1172 } 1173 } else { 1174 t = netdev_priv(dev); 1175 1176 ip6gre_tunnel_unlink(ign, t); 1177 synchronize_net(); 1178 ip6gre_tnl_change(t, &p1, 1); 1179 ip6gre_tunnel_link(ign, t); 1180 netdev_state_change(dev); 1181 } 1182 } 1183 1184 if (t) { 1185 err = 0; 1186 1187 ip6gre_tnl_parm_to_user(&p, &t->parms); 1188 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1189 err = -EFAULT; 1190 } else 1191 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1192 break; 1193 1194 case SIOCDELTUNNEL: 1195 err = -EPERM; 1196 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1197 goto done; 1198 1199 if (dev == ign->fb_tunnel_dev) { 1200 err = -EFAULT; 1201 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1202 goto done; 1203 err = -ENOENT; 1204 ip6gre_tnl_parm_from_user(&p1, &p); 1205 t = ip6gre_tunnel_locate(net, &p1, 0); 1206 if (t == NULL) 1207 goto done; 1208 err = -EPERM; 1209 if (t == netdev_priv(ign->fb_tunnel_dev)) 1210 goto done; 1211 dev = t->dev; 1212 } 1213 unregister_netdevice(dev); 1214 err = 0; 1215 break; 1216 1217 default: 1218 err = -EINVAL; 1219 } 1220 1221 done: 1222 return err; 1223 } 1224 1225 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1226 { 1227 struct ip6_tnl *tunnel = netdev_priv(dev); 1228 if (new_mtu < 68 || 1229 new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen) 1230 return -EINVAL; 1231 dev->mtu = new_mtu; 1232 return 0; 1233 } 1234 1235 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1236 unsigned short type, 1237 const void *daddr, const void *saddr, unsigned int len) 1238 { 1239 struct ip6_tnl *t = netdev_priv(dev); 1240 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1241 __be16 *p = (__be16 *)(ipv6h+1); 1242 1243 *(__be32 *)ipv6h = t->fl.u.ip6.flowlabel | htonl(0x60000000); 1244 ipv6h->hop_limit = t->parms.hop_limit; 1245 ipv6h->nexthdr = NEXTHDR_GRE; 1246 ipv6h->saddr = t->parms.laddr; 1247 ipv6h->daddr = t->parms.raddr; 1248 1249 p[0] = t->parms.o_flags; 1250 p[1] = htons(type); 1251 1252 /* 1253 * Set the source hardware address. 1254 */ 1255 1256 if (saddr) 1257 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1258 if (daddr) 1259 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1260 if (!ipv6_addr_any(&ipv6h->daddr)) 1261 return t->hlen; 1262 1263 return -t->hlen; 1264 } 1265 1266 static const struct header_ops ip6gre_header_ops = { 1267 .create = ip6gre_header, 1268 }; 1269 1270 static const struct net_device_ops ip6gre_netdev_ops = { 1271 .ndo_init = ip6gre_tunnel_init, 1272 .ndo_uninit = ip6gre_tunnel_uninit, 1273 .ndo_start_xmit = ip6gre_tunnel_xmit, 1274 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1275 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1276 .ndo_get_stats64 = ip6gre_get_stats64, 1277 }; 1278 1279 static void ip6gre_dev_free(struct net_device *dev) 1280 { 1281 free_percpu(dev->tstats); 1282 free_netdev(dev); 1283 } 1284 1285 static void ip6gre_tunnel_setup(struct net_device *dev) 1286 { 1287 struct ip6_tnl *t; 1288 1289 dev->netdev_ops = &ip6gre_netdev_ops; 1290 dev->destructor = ip6gre_dev_free; 1291 1292 dev->type = ARPHRD_IP6GRE; 1293 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1294 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1295 t = netdev_priv(dev); 1296 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1297 dev->mtu -= 8; 1298 dev->flags |= IFF_NOARP; 1299 dev->iflink = 0; 1300 dev->addr_len = sizeof(struct in6_addr); 1301 dev->features |= NETIF_F_NETNS_LOCAL; 1302 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1303 } 1304 1305 static int ip6gre_tunnel_init(struct net_device *dev) 1306 { 1307 struct ip6_tnl *tunnel; 1308 1309 tunnel = netdev_priv(dev); 1310 1311 tunnel->dev = dev; 1312 strcpy(tunnel->parms.name, dev->name); 1313 1314 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1315 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1316 1317 if (ipv6_addr_any(&tunnel->parms.raddr)) 1318 dev->header_ops = &ip6gre_header_ops; 1319 1320 dev->tstats = alloc_percpu(struct pcpu_tstats); 1321 if (!dev->tstats) 1322 return -ENOMEM; 1323 1324 return 0; 1325 } 1326 1327 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1328 { 1329 struct ip6_tnl *tunnel = netdev_priv(dev); 1330 1331 tunnel->dev = dev; 1332 strcpy(tunnel->parms.name, dev->name); 1333 1334 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1335 1336 dev_hold(dev); 1337 } 1338 1339 1340 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1341 .handler = ip6gre_rcv, 1342 .err_handler = ip6gre_err, 1343 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1344 }; 1345 1346 static void ip6gre_destroy_tunnels(struct ip6gre_net *ign, 1347 struct list_head *head) 1348 { 1349 int prio; 1350 1351 for (prio = 0; prio < 4; prio++) { 1352 int h; 1353 for (h = 0; h < HASH_SIZE; h++) { 1354 struct ip6_tnl *t; 1355 1356 t = rtnl_dereference(ign->tunnels[prio][h]); 1357 1358 while (t != NULL) { 1359 unregister_netdevice_queue(t->dev, head); 1360 t = rtnl_dereference(t->next); 1361 } 1362 } 1363 } 1364 } 1365 1366 static int __net_init ip6gre_init_net(struct net *net) 1367 { 1368 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1369 int err; 1370 1371 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1372 ip6gre_tunnel_setup); 1373 if (!ign->fb_tunnel_dev) { 1374 err = -ENOMEM; 1375 goto err_alloc_dev; 1376 } 1377 dev_net_set(ign->fb_tunnel_dev, net); 1378 1379 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1380 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1381 1382 err = register_netdev(ign->fb_tunnel_dev); 1383 if (err) 1384 goto err_reg_dev; 1385 1386 rcu_assign_pointer(ign->tunnels_wc[0], 1387 netdev_priv(ign->fb_tunnel_dev)); 1388 return 0; 1389 1390 err_reg_dev: 1391 ip6gre_dev_free(ign->fb_tunnel_dev); 1392 err_alloc_dev: 1393 return err; 1394 } 1395 1396 static void __net_exit ip6gre_exit_net(struct net *net) 1397 { 1398 struct ip6gre_net *ign; 1399 LIST_HEAD(list); 1400 1401 ign = net_generic(net, ip6gre_net_id); 1402 rtnl_lock(); 1403 ip6gre_destroy_tunnels(ign, &list); 1404 unregister_netdevice_many(&list); 1405 rtnl_unlock(); 1406 } 1407 1408 static struct pernet_operations ip6gre_net_ops = { 1409 .init = ip6gre_init_net, 1410 .exit = ip6gre_exit_net, 1411 .id = &ip6gre_net_id, 1412 .size = sizeof(struct ip6gre_net), 1413 }; 1414 1415 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1416 { 1417 __be16 flags; 1418 1419 if (!data) 1420 return 0; 1421 1422 flags = 0; 1423 if (data[IFLA_GRE_IFLAGS]) 1424 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1425 if (data[IFLA_GRE_OFLAGS]) 1426 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1427 if (flags & (GRE_VERSION|GRE_ROUTING)) 1428 return -EINVAL; 1429 1430 return 0; 1431 } 1432 1433 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1434 { 1435 struct in6_addr daddr; 1436 1437 if (tb[IFLA_ADDRESS]) { 1438 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1439 return -EINVAL; 1440 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1441 return -EADDRNOTAVAIL; 1442 } 1443 1444 if (!data) 1445 goto out; 1446 1447 if (data[IFLA_GRE_REMOTE]) { 1448 nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1449 if (ipv6_addr_any(&daddr)) 1450 return -EINVAL; 1451 } 1452 1453 out: 1454 return ip6gre_tunnel_validate(tb, data); 1455 } 1456 1457 1458 static void ip6gre_netlink_parms(struct nlattr *data[], 1459 struct __ip6_tnl_parm *parms) 1460 { 1461 memset(parms, 0, sizeof(*parms)); 1462 1463 if (!data) 1464 return; 1465 1466 if (data[IFLA_GRE_LINK]) 1467 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1468 1469 if (data[IFLA_GRE_IFLAGS]) 1470 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1471 1472 if (data[IFLA_GRE_OFLAGS]) 1473 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1474 1475 if (data[IFLA_GRE_IKEY]) 1476 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1477 1478 if (data[IFLA_GRE_OKEY]) 1479 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1480 1481 if (data[IFLA_GRE_LOCAL]) 1482 nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr)); 1483 1484 if (data[IFLA_GRE_REMOTE]) 1485 nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1486 1487 if (data[IFLA_GRE_TTL]) 1488 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1489 1490 if (data[IFLA_GRE_ENCAP_LIMIT]) 1491 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1492 1493 if (data[IFLA_GRE_FLOWINFO]) 1494 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1495 1496 if (data[IFLA_GRE_FLAGS]) 1497 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1498 } 1499 1500 static int ip6gre_tap_init(struct net_device *dev) 1501 { 1502 struct ip6_tnl *tunnel; 1503 1504 tunnel = netdev_priv(dev); 1505 1506 tunnel->dev = dev; 1507 strcpy(tunnel->parms.name, dev->name); 1508 1509 ip6gre_tnl_link_config(tunnel, 1); 1510 1511 dev->tstats = alloc_percpu(struct pcpu_tstats); 1512 if (!dev->tstats) 1513 return -ENOMEM; 1514 1515 return 0; 1516 } 1517 1518 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1519 .ndo_init = ip6gre_tap_init, 1520 .ndo_uninit = ip6gre_tunnel_uninit, 1521 .ndo_start_xmit = ip6gre_tunnel_xmit, 1522 .ndo_set_mac_address = eth_mac_addr, 1523 .ndo_validate_addr = eth_validate_addr, 1524 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1525 .ndo_get_stats64 = ip6gre_get_stats64, 1526 }; 1527 1528 static void ip6gre_tap_setup(struct net_device *dev) 1529 { 1530 1531 ether_setup(dev); 1532 1533 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1534 dev->destructor = ip6gre_dev_free; 1535 1536 dev->iflink = 0; 1537 dev->features |= NETIF_F_NETNS_LOCAL; 1538 } 1539 1540 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1541 struct nlattr *tb[], struct nlattr *data[]) 1542 { 1543 struct ip6_tnl *nt; 1544 struct net *net = dev_net(dev); 1545 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1546 int err; 1547 1548 nt = netdev_priv(dev); 1549 ip6gre_netlink_parms(data, &nt->parms); 1550 1551 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1552 return -EEXIST; 1553 1554 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1555 eth_hw_addr_random(dev); 1556 1557 nt->dev = dev; 1558 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1559 1560 /* Can use a lockless transmit, unless we generate output sequences */ 1561 if (!(nt->parms.o_flags & GRE_SEQ)) 1562 dev->features |= NETIF_F_LLTX; 1563 1564 err = register_netdevice(dev); 1565 if (err) 1566 goto out; 1567 1568 dev_hold(dev); 1569 ip6gre_tunnel_link(ign, nt); 1570 1571 out: 1572 return err; 1573 } 1574 1575 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1576 struct nlattr *data[]) 1577 { 1578 struct ip6_tnl *t, *nt; 1579 struct net *net = dev_net(dev); 1580 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1581 struct __ip6_tnl_parm p; 1582 1583 if (dev == ign->fb_tunnel_dev) 1584 return -EINVAL; 1585 1586 nt = netdev_priv(dev); 1587 ip6gre_netlink_parms(data, &p); 1588 1589 t = ip6gre_tunnel_locate(net, &p, 0); 1590 1591 if (t) { 1592 if (t->dev != dev) 1593 return -EEXIST; 1594 } else { 1595 t = nt; 1596 1597 ip6gre_tunnel_unlink(ign, t); 1598 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1599 ip6gre_tunnel_link(ign, t); 1600 netdev_state_change(dev); 1601 } 1602 1603 return 0; 1604 } 1605 1606 static size_t ip6gre_get_size(const struct net_device *dev) 1607 { 1608 return 1609 /* IFLA_GRE_LINK */ 1610 nla_total_size(4) + 1611 /* IFLA_GRE_IFLAGS */ 1612 nla_total_size(2) + 1613 /* IFLA_GRE_OFLAGS */ 1614 nla_total_size(2) + 1615 /* IFLA_GRE_IKEY */ 1616 nla_total_size(4) + 1617 /* IFLA_GRE_OKEY */ 1618 nla_total_size(4) + 1619 /* IFLA_GRE_LOCAL */ 1620 nla_total_size(sizeof(struct in6_addr)) + 1621 /* IFLA_GRE_REMOTE */ 1622 nla_total_size(sizeof(struct in6_addr)) + 1623 /* IFLA_GRE_TTL */ 1624 nla_total_size(1) + 1625 /* IFLA_GRE_TOS */ 1626 nla_total_size(1) + 1627 /* IFLA_GRE_ENCAP_LIMIT */ 1628 nla_total_size(1) + 1629 /* IFLA_GRE_FLOWINFO */ 1630 nla_total_size(4) + 1631 /* IFLA_GRE_FLAGS */ 1632 nla_total_size(4) + 1633 0; 1634 } 1635 1636 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1637 { 1638 struct ip6_tnl *t = netdev_priv(dev); 1639 struct __ip6_tnl_parm *p = &t->parms; 1640 1641 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1642 nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) || 1643 nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) || 1644 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1645 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1646 nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->laddr) || 1647 nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->raddr) || 1648 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1649 /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/ 1650 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1651 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1652 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags)) 1653 goto nla_put_failure; 1654 return 0; 1655 1656 nla_put_failure: 1657 return -EMSGSIZE; 1658 } 1659 1660 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1661 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1662 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1663 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1664 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1665 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1666 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1667 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1668 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1669 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1670 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1671 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1672 }; 1673 1674 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1675 .kind = "ip6gre", 1676 .maxtype = IFLA_GRE_MAX, 1677 .policy = ip6gre_policy, 1678 .priv_size = sizeof(struct ip6_tnl), 1679 .setup = ip6gre_tunnel_setup, 1680 .validate = ip6gre_tunnel_validate, 1681 .newlink = ip6gre_newlink, 1682 .changelink = ip6gre_changelink, 1683 .get_size = ip6gre_get_size, 1684 .fill_info = ip6gre_fill_info, 1685 }; 1686 1687 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1688 .kind = "ip6gretap", 1689 .maxtype = IFLA_GRE_MAX, 1690 .policy = ip6gre_policy, 1691 .priv_size = sizeof(struct ip6_tnl), 1692 .setup = ip6gre_tap_setup, 1693 .validate = ip6gre_tap_validate, 1694 .newlink = ip6gre_newlink, 1695 .changelink = ip6gre_changelink, 1696 .get_size = ip6gre_get_size, 1697 .fill_info = ip6gre_fill_info, 1698 }; 1699 1700 /* 1701 * And now the modules code and kernel interface. 1702 */ 1703 1704 static int __init ip6gre_init(void) 1705 { 1706 int err; 1707 1708 pr_info("GRE over IPv6 tunneling driver\n"); 1709 1710 err = register_pernet_device(&ip6gre_net_ops); 1711 if (err < 0) 1712 return err; 1713 1714 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1715 if (err < 0) { 1716 pr_info("%s: can't add protocol\n", __func__); 1717 goto add_proto_failed; 1718 } 1719 1720 err = rtnl_link_register(&ip6gre_link_ops); 1721 if (err < 0) 1722 goto rtnl_link_failed; 1723 1724 err = rtnl_link_register(&ip6gre_tap_ops); 1725 if (err < 0) 1726 goto tap_ops_failed; 1727 1728 out: 1729 return err; 1730 1731 tap_ops_failed: 1732 rtnl_link_unregister(&ip6gre_link_ops); 1733 rtnl_link_failed: 1734 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1735 add_proto_failed: 1736 unregister_pernet_device(&ip6gre_net_ops); 1737 goto out; 1738 } 1739 1740 static void __exit ip6gre_fini(void) 1741 { 1742 rtnl_link_unregister(&ip6gre_tap_ops); 1743 rtnl_link_unregister(&ip6gre_link_ops); 1744 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1745 unregister_pernet_device(&ip6gre_net_ops); 1746 } 1747 1748 module_init(ip6gre_init); 1749 module_exit(ip6gre_fini); 1750 MODULE_LICENSE("GPL"); 1751 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1752 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1753 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1754 MODULE_ALIAS_NETDEV("ip6gre0"); 1755