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