1 /* 2 * GRE over IPv6 protocol decoder. 3 * 4 * Authors: Dmitry Kozlov (xeb@mail.ru) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 * 11 */ 12 13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 14 15 #include <linux/capability.h> 16 #include <linux/module.h> 17 #include <linux/types.h> 18 #include <linux/kernel.h> 19 #include <linux/slab.h> 20 #include <linux/uaccess.h> 21 #include <linux/skbuff.h> 22 #include <linux/netdevice.h> 23 #include <linux/in.h> 24 #include <linux/tcp.h> 25 #include <linux/udp.h> 26 #include <linux/if_arp.h> 27 #include <linux/mroute.h> 28 #include <linux/init.h> 29 #include <linux/in6.h> 30 #include <linux/inetdevice.h> 31 #include <linux/igmp.h> 32 #include <linux/netfilter_ipv4.h> 33 #include <linux/etherdevice.h> 34 #include <linux/if_ether.h> 35 #include <linux/hash.h> 36 #include <linux/if_tunnel.h> 37 #include <linux/ip6_tunnel.h> 38 39 #include <net/sock.h> 40 #include <net/ip.h> 41 #include <net/ip_tunnels.h> 42 #include <net/icmp.h> 43 #include <net/protocol.h> 44 #include <net/addrconf.h> 45 #include <net/arp.h> 46 #include <net/checksum.h> 47 #include <net/dsfield.h> 48 #include <net/inet_ecn.h> 49 #include <net/xfrm.h> 50 #include <net/net_namespace.h> 51 #include <net/netns/generic.h> 52 #include <net/rtnetlink.h> 53 54 #include <net/ipv6.h> 55 #include <net/ip6_fib.h> 56 #include <net/ip6_route.h> 57 #include <net/ip6_tunnel.h> 58 59 60 static bool log_ecn_error = true; 61 module_param(log_ecn_error, bool, 0644); 62 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 63 64 #define HASH_SIZE_SHIFT 5 65 #define HASH_SIZE (1 << HASH_SIZE_SHIFT) 66 67 static int ip6gre_net_id __read_mostly; 68 struct ip6gre_net { 69 struct ip6_tnl __rcu *tunnels[4][HASH_SIZE]; 70 71 struct net_device *fb_tunnel_dev; 72 }; 73 74 static struct rtnl_link_ops ip6gre_link_ops __read_mostly; 75 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly; 76 static int ip6gre_tunnel_init(struct net_device *dev); 77 static void ip6gre_tunnel_setup(struct net_device *dev); 78 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t); 79 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu); 80 81 /* Tunnel hash table */ 82 83 /* 84 4 hash tables: 85 86 3: (remote,local) 87 2: (remote,*) 88 1: (*,local) 89 0: (*,*) 90 91 We require exact key match i.e. if a key is present in packet 92 it will match only tunnel with the same key; if it is not present, 93 it will match only keyless tunnel. 94 95 All keysless packets, if not matched configured keyless tunnels 96 will match fallback tunnel. 97 */ 98 99 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(HASH_SIZE - 1)) 100 static u32 HASH_ADDR(const struct in6_addr *addr) 101 { 102 u32 hash = ipv6_addr_hash(addr); 103 104 return hash_32(hash, HASH_SIZE_SHIFT); 105 } 106 107 #define tunnels_r_l tunnels[3] 108 #define tunnels_r tunnels[2] 109 #define tunnels_l tunnels[1] 110 #define tunnels_wc tunnels[0] 111 112 /* Given src, dst and key, find appropriate for input tunnel. */ 113 114 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev, 115 const struct in6_addr *remote, const struct in6_addr *local, 116 __be32 key, __be16 gre_proto) 117 { 118 struct net *net = dev_net(dev); 119 int link = dev->ifindex; 120 unsigned int h0 = HASH_ADDR(remote); 121 unsigned int h1 = HASH_KEY(key); 122 struct ip6_tnl *t, *cand = NULL; 123 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 124 int dev_type = (gre_proto == htons(ETH_P_TEB)) ? 125 ARPHRD_ETHER : ARPHRD_IP6GRE; 126 int score, cand_score = 4; 127 128 for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) { 129 if (!ipv6_addr_equal(local, &t->parms.laddr) || 130 !ipv6_addr_equal(remote, &t->parms.raddr) || 131 key != t->parms.i_key || 132 !(t->dev->flags & IFF_UP)) 133 continue; 134 135 if (t->dev->type != ARPHRD_IP6GRE && 136 t->dev->type != dev_type) 137 continue; 138 139 score = 0; 140 if (t->parms.link != link) 141 score |= 1; 142 if (t->dev->type != dev_type) 143 score |= 2; 144 if (score == 0) 145 return t; 146 147 if (score < cand_score) { 148 cand = t; 149 cand_score = score; 150 } 151 } 152 153 for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) { 154 if (!ipv6_addr_equal(remote, &t->parms.raddr) || 155 key != t->parms.i_key || 156 !(t->dev->flags & IFF_UP)) 157 continue; 158 159 if (t->dev->type != ARPHRD_IP6GRE && 160 t->dev->type != dev_type) 161 continue; 162 163 score = 0; 164 if (t->parms.link != link) 165 score |= 1; 166 if (t->dev->type != dev_type) 167 score |= 2; 168 if (score == 0) 169 return t; 170 171 if (score < cand_score) { 172 cand = t; 173 cand_score = score; 174 } 175 } 176 177 for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) { 178 if ((!ipv6_addr_equal(local, &t->parms.laddr) && 179 (!ipv6_addr_equal(local, &t->parms.raddr) || 180 !ipv6_addr_is_multicast(local))) || 181 key != t->parms.i_key || 182 !(t->dev->flags & IFF_UP)) 183 continue; 184 185 if (t->dev->type != ARPHRD_IP6GRE && 186 t->dev->type != dev_type) 187 continue; 188 189 score = 0; 190 if (t->parms.link != link) 191 score |= 1; 192 if (t->dev->type != dev_type) 193 score |= 2; 194 if (score == 0) 195 return t; 196 197 if (score < cand_score) { 198 cand = t; 199 cand_score = score; 200 } 201 } 202 203 for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) { 204 if (t->parms.i_key != key || 205 !(t->dev->flags & IFF_UP)) 206 continue; 207 208 if (t->dev->type != ARPHRD_IP6GRE && 209 t->dev->type != dev_type) 210 continue; 211 212 score = 0; 213 if (t->parms.link != link) 214 score |= 1; 215 if (t->dev->type != dev_type) 216 score |= 2; 217 if (score == 0) 218 return t; 219 220 if (score < cand_score) { 221 cand = t; 222 cand_score = score; 223 } 224 } 225 226 if (cand != NULL) 227 return cand; 228 229 dev = ign->fb_tunnel_dev; 230 if (dev->flags & IFF_UP) 231 return netdev_priv(dev); 232 233 return NULL; 234 } 235 236 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign, 237 const struct __ip6_tnl_parm *p) 238 { 239 const struct in6_addr *remote = &p->raddr; 240 const struct in6_addr *local = &p->laddr; 241 unsigned int h = HASH_KEY(p->i_key); 242 int prio = 0; 243 244 if (!ipv6_addr_any(local)) 245 prio |= 1; 246 if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) { 247 prio |= 2; 248 h ^= HASH_ADDR(remote); 249 } 250 251 return &ign->tunnels[prio][h]; 252 } 253 254 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign, 255 const struct ip6_tnl *t) 256 { 257 return __ip6gre_bucket(ign, &t->parms); 258 } 259 260 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t) 261 { 262 struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t); 263 264 rcu_assign_pointer(t->next, rtnl_dereference(*tp)); 265 rcu_assign_pointer(*tp, t); 266 } 267 268 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t) 269 { 270 struct ip6_tnl __rcu **tp; 271 struct ip6_tnl *iter; 272 273 for (tp = ip6gre_bucket(ign, t); 274 (iter = rtnl_dereference(*tp)) != NULL; 275 tp = &iter->next) { 276 if (t == iter) { 277 rcu_assign_pointer(*tp, t->next); 278 break; 279 } 280 } 281 } 282 283 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net, 284 const struct __ip6_tnl_parm *parms, 285 int type) 286 { 287 const struct in6_addr *remote = &parms->raddr; 288 const struct in6_addr *local = &parms->laddr; 289 __be32 key = parms->i_key; 290 int link = parms->link; 291 struct ip6_tnl *t; 292 struct ip6_tnl __rcu **tp; 293 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 294 295 for (tp = __ip6gre_bucket(ign, parms); 296 (t = rtnl_dereference(*tp)) != NULL; 297 tp = &t->next) 298 if (ipv6_addr_equal(local, &t->parms.laddr) && 299 ipv6_addr_equal(remote, &t->parms.raddr) && 300 key == t->parms.i_key && 301 link == t->parms.link && 302 type == t->dev->type) 303 break; 304 305 return t; 306 } 307 308 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net, 309 const struct __ip6_tnl_parm *parms, int create) 310 { 311 struct ip6_tnl *t, *nt; 312 struct net_device *dev; 313 char name[IFNAMSIZ]; 314 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 315 316 t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE); 317 if (t || !create) 318 return t; 319 320 if (parms->name[0]) 321 strlcpy(name, parms->name, IFNAMSIZ); 322 else 323 strcpy(name, "ip6gre%d"); 324 325 dev = alloc_netdev(sizeof(*t), name, ip6gre_tunnel_setup); 326 if (!dev) 327 return NULL; 328 329 dev_net_set(dev, net); 330 331 nt = netdev_priv(dev); 332 nt->parms = *parms; 333 dev->rtnl_link_ops = &ip6gre_link_ops; 334 335 nt->dev = dev; 336 nt->net = dev_net(dev); 337 ip6gre_tnl_link_config(nt, 1); 338 339 if (register_netdevice(dev) < 0) 340 goto failed_free; 341 342 /* Can use a lockless transmit, unless we generate output sequences */ 343 if (!(nt->parms.o_flags & GRE_SEQ)) 344 dev->features |= NETIF_F_LLTX; 345 346 dev_hold(dev); 347 ip6gre_tunnel_link(ign, nt); 348 return nt; 349 350 failed_free: 351 free_netdev(dev); 352 return NULL; 353 } 354 355 static void ip6gre_tunnel_uninit(struct net_device *dev) 356 { 357 struct ip6_tnl *t = netdev_priv(dev); 358 struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id); 359 360 ip6gre_tunnel_unlink(ign, t); 361 dev_put(dev); 362 } 363 364 365 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 366 u8 type, u8 code, int offset, __be32 info) 367 { 368 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 369 __be16 *p = (__be16 *)(skb->data + offset); 370 int grehlen = offset + 4; 371 struct ip6_tnl *t; 372 __be16 flags; 373 374 flags = p[0]; 375 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 376 if (flags&(GRE_VERSION|GRE_ROUTING)) 377 return; 378 if (flags&GRE_KEY) { 379 grehlen += 4; 380 if (flags&GRE_CSUM) 381 grehlen += 4; 382 } 383 } 384 385 /* If only 8 bytes returned, keyed message will be dropped here */ 386 if (!pskb_may_pull(skb, grehlen)) 387 return; 388 ipv6h = (const struct ipv6hdr *)skb->data; 389 p = (__be16 *)(skb->data + offset); 390 391 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 392 flags & GRE_KEY ? 393 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 394 p[1]); 395 if (t == NULL) 396 return; 397 398 switch (type) { 399 __u32 teli; 400 struct ipv6_tlv_tnl_enc_lim *tel; 401 __u32 mtu; 402 case ICMPV6_DEST_UNREACH: 403 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n", 404 t->parms.name); 405 break; 406 case ICMPV6_TIME_EXCEED: 407 if (code == ICMPV6_EXC_HOPLIMIT) { 408 net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 409 t->parms.name); 410 } 411 break; 412 case ICMPV6_PARAMPROB: 413 teli = 0; 414 if (code == ICMPV6_HDR_FIELD) 415 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 416 417 if (teli && teli == info - 2) { 418 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 419 if (tel->encap_limit == 0) { 420 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 421 t->parms.name); 422 } 423 } else { 424 net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 425 t->parms.name); 426 } 427 break; 428 case ICMPV6_PKT_TOOBIG: 429 mtu = info - offset; 430 if (mtu < IPV6_MIN_MTU) 431 mtu = IPV6_MIN_MTU; 432 t->dev->mtu = mtu; 433 break; 434 } 435 436 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 437 t->err_count++; 438 else 439 t->err_count = 1; 440 t->err_time = jiffies; 441 } 442 443 static int ip6gre_rcv(struct sk_buff *skb) 444 { 445 const struct ipv6hdr *ipv6h; 446 u8 *h; 447 __be16 flags; 448 __sum16 csum = 0; 449 __be32 key = 0; 450 u32 seqno = 0; 451 struct ip6_tnl *tunnel; 452 int offset = 4; 453 __be16 gre_proto; 454 int err; 455 456 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 457 goto drop; 458 459 ipv6h = ipv6_hdr(skb); 460 h = skb->data; 461 flags = *(__be16 *)h; 462 463 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 464 /* - Version must be 0. 465 - We do not support routing headers. 466 */ 467 if (flags&(GRE_VERSION|GRE_ROUTING)) 468 goto drop; 469 470 if (flags&GRE_CSUM) { 471 csum = skb_checksum_simple_validate(skb); 472 offset += 4; 473 } 474 if (flags&GRE_KEY) { 475 key = *(__be32 *)(h + offset); 476 offset += 4; 477 } 478 if (flags&GRE_SEQ) { 479 seqno = ntohl(*(__be32 *)(h + offset)); 480 offset += 4; 481 } 482 } 483 484 gre_proto = *(__be16 *)(h + 2); 485 486 tunnel = ip6gre_tunnel_lookup(skb->dev, 487 &ipv6h->saddr, &ipv6h->daddr, key, 488 gre_proto); 489 if (tunnel) { 490 struct pcpu_sw_netstats *tstats; 491 492 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 493 goto drop; 494 495 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 496 tunnel->dev->stats.rx_dropped++; 497 goto drop; 498 } 499 500 skb->protocol = gre_proto; 501 /* WCCP version 1 and 2 protocol decoding. 502 * - Change protocol to IP 503 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 504 */ 505 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 506 skb->protocol = htons(ETH_P_IP); 507 if ((*(h + offset) & 0xF0) != 0x40) 508 offset += 4; 509 } 510 511 skb->mac_header = skb->network_header; 512 __pskb_pull(skb, offset); 513 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 514 515 if (((flags&GRE_CSUM) && csum) || 516 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 517 tunnel->dev->stats.rx_crc_errors++; 518 tunnel->dev->stats.rx_errors++; 519 goto drop; 520 } 521 if (tunnel->parms.i_flags&GRE_SEQ) { 522 if (!(flags&GRE_SEQ) || 523 (tunnel->i_seqno && 524 (s32)(seqno - tunnel->i_seqno) < 0)) { 525 tunnel->dev->stats.rx_fifo_errors++; 526 tunnel->dev->stats.rx_errors++; 527 goto drop; 528 } 529 tunnel->i_seqno = seqno + 1; 530 } 531 532 /* Warning: All skb pointers will be invalidated! */ 533 if (tunnel->dev->type == ARPHRD_ETHER) { 534 if (!pskb_may_pull(skb, ETH_HLEN)) { 535 tunnel->dev->stats.rx_length_errors++; 536 tunnel->dev->stats.rx_errors++; 537 goto drop; 538 } 539 540 ipv6h = ipv6_hdr(skb); 541 skb->protocol = eth_type_trans(skb, tunnel->dev); 542 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 543 } 544 545 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 546 547 skb_reset_network_header(skb); 548 549 err = IP6_ECN_decapsulate(ipv6h, skb); 550 if (unlikely(err)) { 551 if (log_ecn_error) 552 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 553 &ipv6h->saddr, 554 ipv6_get_dsfield(ipv6h)); 555 if (err > 1) { 556 ++tunnel->dev->stats.rx_frame_errors; 557 ++tunnel->dev->stats.rx_errors; 558 goto drop; 559 } 560 } 561 562 tstats = this_cpu_ptr(tunnel->dev->tstats); 563 u64_stats_update_begin(&tstats->syncp); 564 tstats->rx_packets++; 565 tstats->rx_bytes += skb->len; 566 u64_stats_update_end(&tstats->syncp); 567 568 netif_rx(skb); 569 570 return 0; 571 } 572 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 573 574 drop: 575 kfree_skb(skb); 576 return 0; 577 } 578 579 struct ipv6_tel_txoption { 580 struct ipv6_txoptions ops; 581 __u8 dst_opt[8]; 582 }; 583 584 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 585 { 586 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 587 588 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 589 opt->dst_opt[3] = 1; 590 opt->dst_opt[4] = encap_limit; 591 opt->dst_opt[5] = IPV6_TLV_PADN; 592 opt->dst_opt[6] = 1; 593 594 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 595 opt->ops.opt_nflen = 8; 596 } 597 598 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 599 struct net_device *dev, 600 __u8 dsfield, 601 struct flowi6 *fl6, 602 int encap_limit, 603 __u32 *pmtu) 604 { 605 struct ip6_tnl *tunnel = netdev_priv(dev); 606 struct net *net = tunnel->net; 607 struct net_device *tdev; /* Device to other host */ 608 struct ipv6hdr *ipv6h; /* Our new IP header */ 609 unsigned int max_headroom = 0; /* The extra header space needed */ 610 int gre_hlen; 611 struct ipv6_tel_txoption opt; 612 int mtu; 613 struct dst_entry *dst = NULL, *ndst = NULL; 614 struct net_device_stats *stats = &tunnel->dev->stats; 615 int err = -1; 616 u8 proto; 617 struct sk_buff *new_skb; 618 619 if (dev->type == ARPHRD_ETHER) 620 IPCB(skb)->flags = 0; 621 622 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 623 gre_hlen = 0; 624 ipv6h = (struct ipv6hdr *)skb->data; 625 fl6->daddr = ipv6h->daddr; 626 } else { 627 gre_hlen = tunnel->hlen; 628 fl6->daddr = tunnel->parms.raddr; 629 } 630 631 if (!fl6->flowi6_mark) 632 dst = ip6_tnl_dst_check(tunnel); 633 634 if (!dst) { 635 ndst = ip6_route_output(net, NULL, fl6); 636 637 if (ndst->error) 638 goto tx_err_link_failure; 639 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); 640 if (IS_ERR(ndst)) { 641 err = PTR_ERR(ndst); 642 ndst = NULL; 643 goto tx_err_link_failure; 644 } 645 dst = ndst; 646 } 647 648 tdev = dst->dev; 649 650 if (tdev == dev) { 651 stats->collisions++; 652 net_warn_ratelimited("%s: Local routing loop detected!\n", 653 tunnel->parms.name); 654 goto tx_err_dst_release; 655 } 656 657 mtu = dst_mtu(dst) - sizeof(*ipv6h); 658 if (encap_limit >= 0) { 659 max_headroom += 8; 660 mtu -= 8; 661 } 662 if (mtu < IPV6_MIN_MTU) 663 mtu = IPV6_MIN_MTU; 664 if (skb_dst(skb)) 665 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 666 if (skb->len > mtu) { 667 *pmtu = mtu; 668 err = -EMSGSIZE; 669 goto tx_err_dst_release; 670 } 671 672 if (tunnel->err_count > 0) { 673 if (time_before(jiffies, 674 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 675 tunnel->err_count--; 676 677 dst_link_failure(skb); 678 } else 679 tunnel->err_count = 0; 680 } 681 682 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); 683 684 max_headroom += LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; 685 686 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 687 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 688 new_skb = skb_realloc_headroom(skb, max_headroom); 689 if (max_headroom > dev->needed_headroom) 690 dev->needed_headroom = max_headroom; 691 if (!new_skb) 692 goto tx_err_dst_release; 693 694 if (skb->sk) 695 skb_set_owner_w(new_skb, skb->sk); 696 consume_skb(skb); 697 skb = new_skb; 698 } 699 700 if (fl6->flowi6_mark) { 701 skb_dst_set(skb, dst); 702 ndst = NULL; 703 } else { 704 skb_dst_set_noref(skb, dst); 705 } 706 707 proto = NEXTHDR_GRE; 708 if (encap_limit >= 0) { 709 init_tel_txopt(&opt, encap_limit); 710 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 711 } 712 713 if (likely(!skb->encapsulation)) { 714 skb_reset_inner_headers(skb); 715 skb->encapsulation = 1; 716 } 717 718 skb_push(skb, gre_hlen); 719 skb_reset_network_header(skb); 720 skb_set_transport_header(skb, sizeof(*ipv6h)); 721 722 /* 723 * Push down and install the IP header. 724 */ 725 ipv6h = ipv6_hdr(skb); 726 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel); 727 ipv6h->hop_limit = tunnel->parms.hop_limit; 728 ipv6h->nexthdr = proto; 729 ipv6h->saddr = fl6->saddr; 730 ipv6h->daddr = fl6->daddr; 731 732 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 733 ((__be16 *)(ipv6h + 1))[1] = (dev->type == ARPHRD_ETHER) ? 734 htons(ETH_P_TEB) : skb->protocol; 735 736 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 737 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 738 739 if (tunnel->parms.o_flags&GRE_SEQ) { 740 ++tunnel->o_seqno; 741 *ptr = htonl(tunnel->o_seqno); 742 ptr--; 743 } 744 if (tunnel->parms.o_flags&GRE_KEY) { 745 *ptr = tunnel->parms.o_key; 746 ptr--; 747 } 748 if (tunnel->parms.o_flags&GRE_CSUM) { 749 *ptr = 0; 750 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 751 skb->len - sizeof(struct ipv6hdr)); 752 } 753 } 754 755 ip6tunnel_xmit(skb, dev); 756 if (ndst) 757 ip6_tnl_dst_store(tunnel, ndst); 758 return 0; 759 tx_err_link_failure: 760 stats->tx_carrier_errors++; 761 dst_link_failure(skb); 762 tx_err_dst_release: 763 dst_release(ndst); 764 return err; 765 } 766 767 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 768 { 769 struct ip6_tnl *t = netdev_priv(dev); 770 const struct iphdr *iph = ip_hdr(skb); 771 int encap_limit = -1; 772 struct flowi6 fl6; 773 __u8 dsfield; 774 __u32 mtu; 775 int err; 776 777 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 778 encap_limit = t->parms.encap_limit; 779 780 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 781 fl6.flowi6_proto = IPPROTO_IPIP; 782 783 dsfield = ipv4_get_dsfield(iph); 784 785 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 786 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 787 & IPV6_TCLASS_MASK; 788 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 789 fl6.flowi6_mark = skb->mark; 790 791 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 792 if (err != 0) { 793 /* XXX: send ICMP error even if DF is not set. */ 794 if (err == -EMSGSIZE) 795 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 796 htonl(mtu)); 797 return -1; 798 } 799 800 return 0; 801 } 802 803 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 804 { 805 struct ip6_tnl *t = netdev_priv(dev); 806 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 807 int encap_limit = -1; 808 __u16 offset; 809 struct flowi6 fl6; 810 __u8 dsfield; 811 __u32 mtu; 812 int err; 813 814 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 815 return -1; 816 817 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 818 if (offset > 0) { 819 struct ipv6_tlv_tnl_enc_lim *tel; 820 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 821 if (tel->encap_limit == 0) { 822 icmpv6_send(skb, ICMPV6_PARAMPROB, 823 ICMPV6_HDR_FIELD, offset + 2); 824 return -1; 825 } 826 encap_limit = tel->encap_limit - 1; 827 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 828 encap_limit = t->parms.encap_limit; 829 830 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 831 fl6.flowi6_proto = IPPROTO_IPV6; 832 833 dsfield = ipv6_get_dsfield(ipv6h); 834 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 835 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 836 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 837 fl6.flowlabel |= ip6_flowlabel(ipv6h); 838 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 839 fl6.flowi6_mark = skb->mark; 840 841 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 842 if (err != 0) { 843 if (err == -EMSGSIZE) 844 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 845 return -1; 846 } 847 848 return 0; 849 } 850 851 /** 852 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 853 * @t: the outgoing tunnel device 854 * @hdr: IPv6 header from the incoming packet 855 * 856 * Description: 857 * Avoid trivial tunneling loop by checking that tunnel exit-point 858 * doesn't match source of incoming packet. 859 * 860 * Return: 861 * 1 if conflict, 862 * 0 else 863 **/ 864 865 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 866 const struct ipv6hdr *hdr) 867 { 868 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 869 } 870 871 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 872 { 873 struct ip6_tnl *t = netdev_priv(dev); 874 int encap_limit = -1; 875 struct flowi6 fl6; 876 __u32 mtu; 877 int err; 878 879 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 880 encap_limit = t->parms.encap_limit; 881 882 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 883 fl6.flowi6_proto = skb->protocol; 884 885 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 886 887 return err; 888 } 889 890 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 891 struct net_device *dev) 892 { 893 struct ip6_tnl *t = netdev_priv(dev); 894 struct net_device_stats *stats = &t->dev->stats; 895 int ret; 896 897 if (!ip6_tnl_xmit_ctl(t)) 898 goto tx_err; 899 900 switch (skb->protocol) { 901 case htons(ETH_P_IP): 902 ret = ip6gre_xmit_ipv4(skb, dev); 903 break; 904 case htons(ETH_P_IPV6): 905 ret = ip6gre_xmit_ipv6(skb, dev); 906 break; 907 default: 908 ret = ip6gre_xmit_other(skb, dev); 909 break; 910 } 911 912 if (ret < 0) 913 goto tx_err; 914 915 return NETDEV_TX_OK; 916 917 tx_err: 918 stats->tx_errors++; 919 stats->tx_dropped++; 920 kfree_skb(skb); 921 return NETDEV_TX_OK; 922 } 923 924 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 925 { 926 struct net_device *dev = t->dev; 927 struct __ip6_tnl_parm *p = &t->parms; 928 struct flowi6 *fl6 = &t->fl.u.ip6; 929 int addend = sizeof(struct ipv6hdr) + 4; 930 931 if (dev->type != ARPHRD_ETHER) { 932 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 933 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 934 } 935 936 /* Set up flowi template */ 937 fl6->saddr = p->laddr; 938 fl6->daddr = p->raddr; 939 fl6->flowi6_oif = p->link; 940 fl6->flowlabel = 0; 941 942 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 943 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 944 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 945 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 946 947 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 948 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 949 950 if (p->flags&IP6_TNL_F_CAP_XMIT && 951 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 952 dev->flags |= IFF_POINTOPOINT; 953 else 954 dev->flags &= ~IFF_POINTOPOINT; 955 956 dev->iflink = p->link; 957 958 /* Precalculate GRE options length */ 959 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 960 if (t->parms.o_flags&GRE_CSUM) 961 addend += 4; 962 if (t->parms.o_flags&GRE_KEY) 963 addend += 4; 964 if (t->parms.o_flags&GRE_SEQ) 965 addend += 4; 966 } 967 t->hlen = addend; 968 969 if (p->flags & IP6_TNL_F_CAP_XMIT) { 970 int strict = (ipv6_addr_type(&p->raddr) & 971 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 972 973 struct rt6_info *rt = rt6_lookup(t->net, 974 &p->raddr, &p->laddr, 975 p->link, strict); 976 977 if (rt == NULL) 978 return; 979 980 if (rt->dst.dev) { 981 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 982 983 if (set_mtu) { 984 dev->mtu = rt->dst.dev->mtu - addend; 985 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 986 dev->mtu -= 8; 987 988 if (dev->mtu < IPV6_MIN_MTU) 989 dev->mtu = IPV6_MIN_MTU; 990 } 991 } 992 ip6_rt_put(rt); 993 } 994 } 995 996 static int ip6gre_tnl_change(struct ip6_tnl *t, 997 const struct __ip6_tnl_parm *p, int set_mtu) 998 { 999 t->parms.laddr = p->laddr; 1000 t->parms.raddr = p->raddr; 1001 t->parms.flags = p->flags; 1002 t->parms.hop_limit = p->hop_limit; 1003 t->parms.encap_limit = p->encap_limit; 1004 t->parms.flowinfo = p->flowinfo; 1005 t->parms.link = p->link; 1006 t->parms.proto = p->proto; 1007 t->parms.i_key = p->i_key; 1008 t->parms.o_key = p->o_key; 1009 t->parms.i_flags = p->i_flags; 1010 t->parms.o_flags = p->o_flags; 1011 ip6_tnl_dst_reset(t); 1012 ip6gre_tnl_link_config(t, set_mtu); 1013 return 0; 1014 } 1015 1016 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1017 const struct ip6_tnl_parm2 *u) 1018 { 1019 p->laddr = u->laddr; 1020 p->raddr = u->raddr; 1021 p->flags = u->flags; 1022 p->hop_limit = u->hop_limit; 1023 p->encap_limit = u->encap_limit; 1024 p->flowinfo = u->flowinfo; 1025 p->link = u->link; 1026 p->i_key = u->i_key; 1027 p->o_key = u->o_key; 1028 p->i_flags = u->i_flags; 1029 p->o_flags = u->o_flags; 1030 memcpy(p->name, u->name, sizeof(u->name)); 1031 } 1032 1033 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1034 const struct __ip6_tnl_parm *p) 1035 { 1036 u->proto = IPPROTO_GRE; 1037 u->laddr = p->laddr; 1038 u->raddr = p->raddr; 1039 u->flags = p->flags; 1040 u->hop_limit = p->hop_limit; 1041 u->encap_limit = p->encap_limit; 1042 u->flowinfo = p->flowinfo; 1043 u->link = p->link; 1044 u->i_key = p->i_key; 1045 u->o_key = p->o_key; 1046 u->i_flags = p->i_flags; 1047 u->o_flags = p->o_flags; 1048 memcpy(u->name, p->name, sizeof(u->name)); 1049 } 1050 1051 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1052 struct ifreq *ifr, int cmd) 1053 { 1054 int err = 0; 1055 struct ip6_tnl_parm2 p; 1056 struct __ip6_tnl_parm p1; 1057 struct ip6_tnl *t = netdev_priv(dev); 1058 struct net *net = t->net; 1059 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1060 1061 switch (cmd) { 1062 case SIOCGETTUNNEL: 1063 if (dev == ign->fb_tunnel_dev) { 1064 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1065 err = -EFAULT; 1066 break; 1067 } 1068 ip6gre_tnl_parm_from_user(&p1, &p); 1069 t = ip6gre_tunnel_locate(net, &p1, 0); 1070 if (t == NULL) 1071 t = netdev_priv(dev); 1072 } 1073 memset(&p, 0, sizeof(p)); 1074 ip6gre_tnl_parm_to_user(&p, &t->parms); 1075 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1076 err = -EFAULT; 1077 break; 1078 1079 case SIOCADDTUNNEL: 1080 case SIOCCHGTUNNEL: 1081 err = -EPERM; 1082 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1083 goto done; 1084 1085 err = -EFAULT; 1086 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1087 goto done; 1088 1089 err = -EINVAL; 1090 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1091 goto done; 1092 1093 if (!(p.i_flags&GRE_KEY)) 1094 p.i_key = 0; 1095 if (!(p.o_flags&GRE_KEY)) 1096 p.o_key = 0; 1097 1098 ip6gre_tnl_parm_from_user(&p1, &p); 1099 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1100 1101 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1102 if (t != NULL) { 1103 if (t->dev != dev) { 1104 err = -EEXIST; 1105 break; 1106 } 1107 } else { 1108 t = netdev_priv(dev); 1109 1110 ip6gre_tunnel_unlink(ign, t); 1111 synchronize_net(); 1112 ip6gre_tnl_change(t, &p1, 1); 1113 ip6gre_tunnel_link(ign, t); 1114 netdev_state_change(dev); 1115 } 1116 } 1117 1118 if (t) { 1119 err = 0; 1120 1121 memset(&p, 0, sizeof(p)); 1122 ip6gre_tnl_parm_to_user(&p, &t->parms); 1123 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1124 err = -EFAULT; 1125 } else 1126 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1127 break; 1128 1129 case SIOCDELTUNNEL: 1130 err = -EPERM; 1131 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1132 goto done; 1133 1134 if (dev == ign->fb_tunnel_dev) { 1135 err = -EFAULT; 1136 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1137 goto done; 1138 err = -ENOENT; 1139 ip6gre_tnl_parm_from_user(&p1, &p); 1140 t = ip6gre_tunnel_locate(net, &p1, 0); 1141 if (t == NULL) 1142 goto done; 1143 err = -EPERM; 1144 if (t == netdev_priv(ign->fb_tunnel_dev)) 1145 goto done; 1146 dev = t->dev; 1147 } 1148 unregister_netdevice(dev); 1149 err = 0; 1150 break; 1151 1152 default: 1153 err = -EINVAL; 1154 } 1155 1156 done: 1157 return err; 1158 } 1159 1160 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1161 { 1162 if (new_mtu < 68 || 1163 new_mtu > 0xFFF8 - dev->hard_header_len) 1164 return -EINVAL; 1165 dev->mtu = new_mtu; 1166 return 0; 1167 } 1168 1169 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1170 unsigned short type, 1171 const void *daddr, const void *saddr, unsigned int len) 1172 { 1173 struct ip6_tnl *t = netdev_priv(dev); 1174 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1175 __be16 *p = (__be16 *)(ipv6h+1); 1176 1177 ip6_flow_hdr(ipv6h, 0, t->fl.u.ip6.flowlabel); 1178 ipv6h->hop_limit = t->parms.hop_limit; 1179 ipv6h->nexthdr = NEXTHDR_GRE; 1180 ipv6h->saddr = t->parms.laddr; 1181 ipv6h->daddr = t->parms.raddr; 1182 1183 p[0] = t->parms.o_flags; 1184 p[1] = htons(type); 1185 1186 /* 1187 * Set the source hardware address. 1188 */ 1189 1190 if (saddr) 1191 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1192 if (daddr) 1193 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1194 if (!ipv6_addr_any(&ipv6h->daddr)) 1195 return t->hlen; 1196 1197 return -t->hlen; 1198 } 1199 1200 static const struct header_ops ip6gre_header_ops = { 1201 .create = ip6gre_header, 1202 }; 1203 1204 static const struct net_device_ops ip6gre_netdev_ops = { 1205 .ndo_init = ip6gre_tunnel_init, 1206 .ndo_uninit = ip6gre_tunnel_uninit, 1207 .ndo_start_xmit = ip6gre_tunnel_xmit, 1208 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1209 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1210 .ndo_get_stats64 = ip_tunnel_get_stats64, 1211 }; 1212 1213 static void ip6gre_dev_free(struct net_device *dev) 1214 { 1215 free_percpu(dev->tstats); 1216 free_netdev(dev); 1217 } 1218 1219 static void ip6gre_tunnel_setup(struct net_device *dev) 1220 { 1221 struct ip6_tnl *t; 1222 1223 dev->netdev_ops = &ip6gre_netdev_ops; 1224 dev->destructor = ip6gre_dev_free; 1225 1226 dev->type = ARPHRD_IP6GRE; 1227 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1228 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1229 t = netdev_priv(dev); 1230 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1231 dev->mtu -= 8; 1232 dev->flags |= IFF_NOARP; 1233 dev->iflink = 0; 1234 dev->addr_len = sizeof(struct in6_addr); 1235 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 1236 } 1237 1238 static int ip6gre_tunnel_init(struct net_device *dev) 1239 { 1240 struct ip6_tnl *tunnel; 1241 int i; 1242 1243 tunnel = netdev_priv(dev); 1244 1245 tunnel->dev = dev; 1246 tunnel->net = dev_net(dev); 1247 strcpy(tunnel->parms.name, dev->name); 1248 1249 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1250 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1251 1252 if (ipv6_addr_any(&tunnel->parms.raddr)) 1253 dev->header_ops = &ip6gre_header_ops; 1254 1255 dev->tstats = alloc_percpu(struct pcpu_sw_netstats); 1256 if (!dev->tstats) 1257 return -ENOMEM; 1258 1259 for_each_possible_cpu(i) { 1260 struct pcpu_sw_netstats *ip6gre_tunnel_stats; 1261 ip6gre_tunnel_stats = per_cpu_ptr(dev->tstats, i); 1262 u64_stats_init(&ip6gre_tunnel_stats->syncp); 1263 } 1264 1265 1266 return 0; 1267 } 1268 1269 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1270 { 1271 struct ip6_tnl *tunnel = netdev_priv(dev); 1272 1273 tunnel->dev = dev; 1274 tunnel->net = dev_net(dev); 1275 strcpy(tunnel->parms.name, dev->name); 1276 1277 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1278 1279 dev_hold(dev); 1280 } 1281 1282 1283 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1284 .handler = ip6gre_rcv, 1285 .err_handler = ip6gre_err, 1286 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1287 }; 1288 1289 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 1290 { 1291 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1292 struct net_device *dev, *aux; 1293 int prio; 1294 1295 for_each_netdev_safe(net, dev, aux) 1296 if (dev->rtnl_link_ops == &ip6gre_link_ops || 1297 dev->rtnl_link_ops == &ip6gre_tap_ops) 1298 unregister_netdevice_queue(dev, head); 1299 1300 for (prio = 0; prio < 4; prio++) { 1301 int h; 1302 for (h = 0; h < HASH_SIZE; h++) { 1303 struct ip6_tnl *t; 1304 1305 t = rtnl_dereference(ign->tunnels[prio][h]); 1306 1307 while (t != NULL) { 1308 /* If dev is in the same netns, it has already 1309 * been added to the list by the previous loop. 1310 */ 1311 if (!net_eq(dev_net(t->dev), net)) 1312 unregister_netdevice_queue(t->dev, 1313 head); 1314 t = rtnl_dereference(t->next); 1315 } 1316 } 1317 } 1318 } 1319 1320 static int __net_init ip6gre_init_net(struct net *net) 1321 { 1322 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1323 int err; 1324 1325 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1326 ip6gre_tunnel_setup); 1327 if (!ign->fb_tunnel_dev) { 1328 err = -ENOMEM; 1329 goto err_alloc_dev; 1330 } 1331 dev_net_set(ign->fb_tunnel_dev, net); 1332 /* FB netdevice is special: we have one, and only one per netns. 1333 * Allowing to move it to another netns is clearly unsafe. 1334 */ 1335 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1336 1337 1338 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1339 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1340 1341 err = register_netdev(ign->fb_tunnel_dev); 1342 if (err) 1343 goto err_reg_dev; 1344 1345 rcu_assign_pointer(ign->tunnels_wc[0], 1346 netdev_priv(ign->fb_tunnel_dev)); 1347 return 0; 1348 1349 err_reg_dev: 1350 ip6gre_dev_free(ign->fb_tunnel_dev); 1351 err_alloc_dev: 1352 return err; 1353 } 1354 1355 static void __net_exit ip6gre_exit_net(struct net *net) 1356 { 1357 LIST_HEAD(list); 1358 1359 rtnl_lock(); 1360 ip6gre_destroy_tunnels(net, &list); 1361 unregister_netdevice_many(&list); 1362 rtnl_unlock(); 1363 } 1364 1365 static struct pernet_operations ip6gre_net_ops = { 1366 .init = ip6gre_init_net, 1367 .exit = ip6gre_exit_net, 1368 .id = &ip6gre_net_id, 1369 .size = sizeof(struct ip6gre_net), 1370 }; 1371 1372 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1373 { 1374 __be16 flags; 1375 1376 if (!data) 1377 return 0; 1378 1379 flags = 0; 1380 if (data[IFLA_GRE_IFLAGS]) 1381 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1382 if (data[IFLA_GRE_OFLAGS]) 1383 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1384 if (flags & (GRE_VERSION|GRE_ROUTING)) 1385 return -EINVAL; 1386 1387 return 0; 1388 } 1389 1390 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1391 { 1392 struct in6_addr daddr; 1393 1394 if (tb[IFLA_ADDRESS]) { 1395 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1396 return -EINVAL; 1397 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1398 return -EADDRNOTAVAIL; 1399 } 1400 1401 if (!data) 1402 goto out; 1403 1404 if (data[IFLA_GRE_REMOTE]) { 1405 nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1406 if (ipv6_addr_any(&daddr)) 1407 return -EINVAL; 1408 } 1409 1410 out: 1411 return ip6gre_tunnel_validate(tb, data); 1412 } 1413 1414 1415 static void ip6gre_netlink_parms(struct nlattr *data[], 1416 struct __ip6_tnl_parm *parms) 1417 { 1418 memset(parms, 0, sizeof(*parms)); 1419 1420 if (!data) 1421 return; 1422 1423 if (data[IFLA_GRE_LINK]) 1424 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1425 1426 if (data[IFLA_GRE_IFLAGS]) 1427 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1428 1429 if (data[IFLA_GRE_OFLAGS]) 1430 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1431 1432 if (data[IFLA_GRE_IKEY]) 1433 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1434 1435 if (data[IFLA_GRE_OKEY]) 1436 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1437 1438 if (data[IFLA_GRE_LOCAL]) 1439 nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr)); 1440 1441 if (data[IFLA_GRE_REMOTE]) 1442 nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1443 1444 if (data[IFLA_GRE_TTL]) 1445 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1446 1447 if (data[IFLA_GRE_ENCAP_LIMIT]) 1448 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1449 1450 if (data[IFLA_GRE_FLOWINFO]) 1451 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1452 1453 if (data[IFLA_GRE_FLAGS]) 1454 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1455 } 1456 1457 static int ip6gre_tap_init(struct net_device *dev) 1458 { 1459 struct ip6_tnl *tunnel; 1460 1461 tunnel = netdev_priv(dev); 1462 1463 tunnel->dev = dev; 1464 tunnel->net = dev_net(dev); 1465 strcpy(tunnel->parms.name, dev->name); 1466 1467 ip6gre_tnl_link_config(tunnel, 1); 1468 1469 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1470 if (!dev->tstats) 1471 return -ENOMEM; 1472 1473 return 0; 1474 } 1475 1476 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1477 .ndo_init = ip6gre_tap_init, 1478 .ndo_uninit = ip6gre_tunnel_uninit, 1479 .ndo_start_xmit = ip6gre_tunnel_xmit, 1480 .ndo_set_mac_address = eth_mac_addr, 1481 .ndo_validate_addr = eth_validate_addr, 1482 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1483 .ndo_get_stats64 = ip_tunnel_get_stats64, 1484 }; 1485 1486 static void ip6gre_tap_setup(struct net_device *dev) 1487 { 1488 1489 ether_setup(dev); 1490 1491 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1492 dev->destructor = ip6gre_dev_free; 1493 1494 dev->iflink = 0; 1495 dev->features |= NETIF_F_NETNS_LOCAL; 1496 } 1497 1498 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1499 struct nlattr *tb[], struct nlattr *data[]) 1500 { 1501 struct ip6_tnl *nt; 1502 struct net *net = dev_net(dev); 1503 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1504 int err; 1505 1506 nt = netdev_priv(dev); 1507 ip6gre_netlink_parms(data, &nt->parms); 1508 1509 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1510 return -EEXIST; 1511 1512 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1513 eth_hw_addr_random(dev); 1514 1515 nt->dev = dev; 1516 nt->net = dev_net(dev); 1517 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1518 1519 /* Can use a lockless transmit, unless we generate output sequences */ 1520 if (!(nt->parms.o_flags & GRE_SEQ)) 1521 dev->features |= NETIF_F_LLTX; 1522 1523 err = register_netdevice(dev); 1524 if (err) 1525 goto out; 1526 1527 dev_hold(dev); 1528 ip6gre_tunnel_link(ign, nt); 1529 1530 out: 1531 return err; 1532 } 1533 1534 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1535 struct nlattr *data[]) 1536 { 1537 struct ip6_tnl *t, *nt = netdev_priv(dev); 1538 struct net *net = nt->net; 1539 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1540 struct __ip6_tnl_parm p; 1541 1542 if (dev == ign->fb_tunnel_dev) 1543 return -EINVAL; 1544 1545 ip6gre_netlink_parms(data, &p); 1546 1547 t = ip6gre_tunnel_locate(net, &p, 0); 1548 1549 if (t) { 1550 if (t->dev != dev) 1551 return -EEXIST; 1552 } else { 1553 t = nt; 1554 1555 ip6gre_tunnel_unlink(ign, t); 1556 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1557 ip6gre_tunnel_link(ign, t); 1558 netdev_state_change(dev); 1559 } 1560 1561 return 0; 1562 } 1563 1564 static void ip6gre_dellink(struct net_device *dev, struct list_head *head) 1565 { 1566 struct net *net = dev_net(dev); 1567 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1568 1569 if (dev != ign->fb_tunnel_dev) 1570 unregister_netdevice_queue(dev, head); 1571 } 1572 1573 static size_t ip6gre_get_size(const struct net_device *dev) 1574 { 1575 return 1576 /* IFLA_GRE_LINK */ 1577 nla_total_size(4) + 1578 /* IFLA_GRE_IFLAGS */ 1579 nla_total_size(2) + 1580 /* IFLA_GRE_OFLAGS */ 1581 nla_total_size(2) + 1582 /* IFLA_GRE_IKEY */ 1583 nla_total_size(4) + 1584 /* IFLA_GRE_OKEY */ 1585 nla_total_size(4) + 1586 /* IFLA_GRE_LOCAL */ 1587 nla_total_size(sizeof(struct in6_addr)) + 1588 /* IFLA_GRE_REMOTE */ 1589 nla_total_size(sizeof(struct in6_addr)) + 1590 /* IFLA_GRE_TTL */ 1591 nla_total_size(1) + 1592 /* IFLA_GRE_TOS */ 1593 nla_total_size(1) + 1594 /* IFLA_GRE_ENCAP_LIMIT */ 1595 nla_total_size(1) + 1596 /* IFLA_GRE_FLOWINFO */ 1597 nla_total_size(4) + 1598 /* IFLA_GRE_FLAGS */ 1599 nla_total_size(4) + 1600 0; 1601 } 1602 1603 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1604 { 1605 struct ip6_tnl *t = netdev_priv(dev); 1606 struct __ip6_tnl_parm *p = &t->parms; 1607 1608 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1609 nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) || 1610 nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) || 1611 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1612 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1613 nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->laddr) || 1614 nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->raddr) || 1615 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1616 /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/ 1617 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1618 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1619 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags)) 1620 goto nla_put_failure; 1621 return 0; 1622 1623 nla_put_failure: 1624 return -EMSGSIZE; 1625 } 1626 1627 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1628 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1629 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1630 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1631 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1632 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1633 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1634 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1635 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1636 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1637 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1638 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1639 }; 1640 1641 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1642 .kind = "ip6gre", 1643 .maxtype = IFLA_GRE_MAX, 1644 .policy = ip6gre_policy, 1645 .priv_size = sizeof(struct ip6_tnl), 1646 .setup = ip6gre_tunnel_setup, 1647 .validate = ip6gre_tunnel_validate, 1648 .newlink = ip6gre_newlink, 1649 .changelink = ip6gre_changelink, 1650 .dellink = ip6gre_dellink, 1651 .get_size = ip6gre_get_size, 1652 .fill_info = ip6gre_fill_info, 1653 }; 1654 1655 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1656 .kind = "ip6gretap", 1657 .maxtype = IFLA_GRE_MAX, 1658 .policy = ip6gre_policy, 1659 .priv_size = sizeof(struct ip6_tnl), 1660 .setup = ip6gre_tap_setup, 1661 .validate = ip6gre_tap_validate, 1662 .newlink = ip6gre_newlink, 1663 .changelink = ip6gre_changelink, 1664 .get_size = ip6gre_get_size, 1665 .fill_info = ip6gre_fill_info, 1666 }; 1667 1668 /* 1669 * And now the modules code and kernel interface. 1670 */ 1671 1672 static int __init ip6gre_init(void) 1673 { 1674 int err; 1675 1676 pr_info("GRE over IPv6 tunneling driver\n"); 1677 1678 err = register_pernet_device(&ip6gre_net_ops); 1679 if (err < 0) 1680 return err; 1681 1682 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1683 if (err < 0) { 1684 pr_info("%s: can't add protocol\n", __func__); 1685 goto add_proto_failed; 1686 } 1687 1688 err = rtnl_link_register(&ip6gre_link_ops); 1689 if (err < 0) 1690 goto rtnl_link_failed; 1691 1692 err = rtnl_link_register(&ip6gre_tap_ops); 1693 if (err < 0) 1694 goto tap_ops_failed; 1695 1696 out: 1697 return err; 1698 1699 tap_ops_failed: 1700 rtnl_link_unregister(&ip6gre_link_ops); 1701 rtnl_link_failed: 1702 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1703 add_proto_failed: 1704 unregister_pernet_device(&ip6gre_net_ops); 1705 goto out; 1706 } 1707 1708 static void __exit ip6gre_fini(void) 1709 { 1710 rtnl_link_unregister(&ip6gre_tap_ops); 1711 rtnl_link_unregister(&ip6gre_link_ops); 1712 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1713 unregister_pernet_device(&ip6gre_net_ops); 1714 } 1715 1716 module_init(ip6gre_init); 1717 module_exit(ip6gre_fini); 1718 MODULE_LICENSE("GPL"); 1719 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1720 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1721 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1722 MODULE_ALIAS_NETDEV("ip6gre0"); 1723