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 NULL; 319 if (t || !create) 320 return t; 321 322 if (parms->name[0]) 323 strlcpy(name, parms->name, IFNAMSIZ); 324 else 325 strcpy(name, "ip6gre%d"); 326 327 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, 328 ip6gre_tunnel_setup); 329 if (!dev) 330 return NULL; 331 332 dev_net_set(dev, net); 333 334 nt = netdev_priv(dev); 335 nt->parms = *parms; 336 dev->rtnl_link_ops = &ip6gre_link_ops; 337 338 nt->dev = dev; 339 nt->net = dev_net(dev); 340 ip6gre_tnl_link_config(nt, 1); 341 342 if (register_netdevice(dev) < 0) 343 goto failed_free; 344 345 /* Can use a lockless transmit, unless we generate output sequences */ 346 if (!(nt->parms.o_flags & GRE_SEQ)) 347 dev->features |= NETIF_F_LLTX; 348 349 dev_hold(dev); 350 ip6gre_tunnel_link(ign, nt); 351 return nt; 352 353 failed_free: 354 free_netdev(dev); 355 return NULL; 356 } 357 358 static void ip6gre_tunnel_uninit(struct net_device *dev) 359 { 360 struct ip6_tnl *t = netdev_priv(dev); 361 struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id); 362 363 ip6gre_tunnel_unlink(ign, t); 364 dev_put(dev); 365 } 366 367 368 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 369 u8 type, u8 code, int offset, __be32 info) 370 { 371 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data; 372 __be16 *p = (__be16 *)(skb->data + offset); 373 int grehlen = offset + 4; 374 struct ip6_tnl *t; 375 __be16 flags; 376 377 flags = p[0]; 378 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { 379 if (flags&(GRE_VERSION|GRE_ROUTING)) 380 return; 381 if (flags&GRE_KEY) { 382 grehlen += 4; 383 if (flags&GRE_CSUM) 384 grehlen += 4; 385 } 386 } 387 388 /* If only 8 bytes returned, keyed message will be dropped here */ 389 if (!pskb_may_pull(skb, grehlen)) 390 return; 391 ipv6h = (const struct ipv6hdr *)skb->data; 392 p = (__be16 *)(skb->data + offset); 393 394 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 395 flags & GRE_KEY ? 396 *(((__be32 *)p) + (grehlen / 4) - 1) : 0, 397 p[1]); 398 if (t == NULL) 399 return; 400 401 switch (type) { 402 __u32 teli; 403 struct ipv6_tlv_tnl_enc_lim *tel; 404 __u32 mtu; 405 case ICMPV6_DEST_UNREACH: 406 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n", 407 t->parms.name); 408 break; 409 case ICMPV6_TIME_EXCEED: 410 if (code == ICMPV6_EXC_HOPLIMIT) { 411 net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 412 t->parms.name); 413 } 414 break; 415 case ICMPV6_PARAMPROB: 416 teli = 0; 417 if (code == ICMPV6_HDR_FIELD) 418 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 419 420 if (teli && teli == info - 2) { 421 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 422 if (tel->encap_limit == 0) { 423 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 424 t->parms.name); 425 } 426 } else { 427 net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 428 t->parms.name); 429 } 430 break; 431 case ICMPV6_PKT_TOOBIG: 432 mtu = info - offset; 433 if (mtu < IPV6_MIN_MTU) 434 mtu = IPV6_MIN_MTU; 435 t->dev->mtu = mtu; 436 break; 437 } 438 439 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 440 t->err_count++; 441 else 442 t->err_count = 1; 443 t->err_time = jiffies; 444 } 445 446 static int ip6gre_rcv(struct sk_buff *skb) 447 { 448 const struct ipv6hdr *ipv6h; 449 u8 *h; 450 __be16 flags; 451 __sum16 csum = 0; 452 __be32 key = 0; 453 u32 seqno = 0; 454 struct ip6_tnl *tunnel; 455 int offset = 4; 456 __be16 gre_proto; 457 int err; 458 459 if (!pskb_may_pull(skb, sizeof(struct in6_addr))) 460 goto drop; 461 462 ipv6h = ipv6_hdr(skb); 463 h = skb->data; 464 flags = *(__be16 *)h; 465 466 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) { 467 /* - Version must be 0. 468 - We do not support routing headers. 469 */ 470 if (flags&(GRE_VERSION|GRE_ROUTING)) 471 goto drop; 472 473 if (flags&GRE_CSUM) { 474 csum = skb_checksum_simple_validate(skb); 475 offset += 4; 476 } 477 if (flags&GRE_KEY) { 478 key = *(__be32 *)(h + offset); 479 offset += 4; 480 } 481 if (flags&GRE_SEQ) { 482 seqno = ntohl(*(__be32 *)(h + offset)); 483 offset += 4; 484 } 485 } 486 487 gre_proto = *(__be16 *)(h + 2); 488 489 tunnel = ip6gre_tunnel_lookup(skb->dev, 490 &ipv6h->saddr, &ipv6h->daddr, key, 491 gre_proto); 492 if (tunnel) { 493 struct pcpu_sw_netstats *tstats; 494 495 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 496 goto drop; 497 498 if (!ip6_tnl_rcv_ctl(tunnel, &ipv6h->daddr, &ipv6h->saddr)) { 499 tunnel->dev->stats.rx_dropped++; 500 goto drop; 501 } 502 503 skb->protocol = gre_proto; 504 /* WCCP version 1 and 2 protocol decoding. 505 * - Change protocol to IPv6 506 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header 507 */ 508 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) { 509 skb->protocol = htons(ETH_P_IPV6); 510 if ((*(h + offset) & 0xF0) != 0x40) 511 offset += 4; 512 } 513 514 skb->mac_header = skb->network_header; 515 __pskb_pull(skb, offset); 516 skb_postpull_rcsum(skb, skb_transport_header(skb), offset); 517 518 if (((flags&GRE_CSUM) && csum) || 519 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) { 520 tunnel->dev->stats.rx_crc_errors++; 521 tunnel->dev->stats.rx_errors++; 522 goto drop; 523 } 524 if (tunnel->parms.i_flags&GRE_SEQ) { 525 if (!(flags&GRE_SEQ) || 526 (tunnel->i_seqno && 527 (s32)(seqno - tunnel->i_seqno) < 0)) { 528 tunnel->dev->stats.rx_fifo_errors++; 529 tunnel->dev->stats.rx_errors++; 530 goto drop; 531 } 532 tunnel->i_seqno = seqno + 1; 533 } 534 535 /* Warning: All skb pointers will be invalidated! */ 536 if (tunnel->dev->type == ARPHRD_ETHER) { 537 if (!pskb_may_pull(skb, ETH_HLEN)) { 538 tunnel->dev->stats.rx_length_errors++; 539 tunnel->dev->stats.rx_errors++; 540 goto drop; 541 } 542 543 ipv6h = ipv6_hdr(skb); 544 skb->protocol = eth_type_trans(skb, tunnel->dev); 545 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 546 } 547 548 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net); 549 550 skb_reset_network_header(skb); 551 552 err = IP6_ECN_decapsulate(ipv6h, skb); 553 if (unlikely(err)) { 554 if (log_ecn_error) 555 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", 556 &ipv6h->saddr, 557 ipv6_get_dsfield(ipv6h)); 558 if (err > 1) { 559 ++tunnel->dev->stats.rx_frame_errors; 560 ++tunnel->dev->stats.rx_errors; 561 goto drop; 562 } 563 } 564 565 tstats = this_cpu_ptr(tunnel->dev->tstats); 566 u64_stats_update_begin(&tstats->syncp); 567 tstats->rx_packets++; 568 tstats->rx_bytes += skb->len; 569 u64_stats_update_end(&tstats->syncp); 570 571 netif_rx(skb); 572 573 return 0; 574 } 575 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 576 577 drop: 578 kfree_skb(skb); 579 return 0; 580 } 581 582 struct ipv6_tel_txoption { 583 struct ipv6_txoptions ops; 584 __u8 dst_opt[8]; 585 }; 586 587 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) 588 { 589 memset(opt, 0, sizeof(struct ipv6_tel_txoption)); 590 591 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; 592 opt->dst_opt[3] = 1; 593 opt->dst_opt[4] = encap_limit; 594 opt->dst_opt[5] = IPV6_TLV_PADN; 595 opt->dst_opt[6] = 1; 596 597 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; 598 opt->ops.opt_nflen = 8; 599 } 600 601 static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, 602 struct net_device *dev, 603 __u8 dsfield, 604 struct flowi6 *fl6, 605 int encap_limit, 606 __u32 *pmtu) 607 { 608 struct ip6_tnl *tunnel = netdev_priv(dev); 609 struct net *net = tunnel->net; 610 struct net_device *tdev; /* Device to other host */ 611 struct ipv6hdr *ipv6h; /* Our new IP header */ 612 unsigned int max_headroom = 0; /* The extra header space needed */ 613 int gre_hlen; 614 struct ipv6_tel_txoption opt; 615 int mtu; 616 struct dst_entry *dst = NULL, *ndst = NULL; 617 struct net_device_stats *stats = &tunnel->dev->stats; 618 int err = -1; 619 u8 proto; 620 struct sk_buff *new_skb; 621 __be16 protocol; 622 623 if (dev->type == ARPHRD_ETHER) 624 IPCB(skb)->flags = 0; 625 626 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { 627 gre_hlen = 0; 628 ipv6h = (struct ipv6hdr *)skb->data; 629 fl6->daddr = ipv6h->daddr; 630 } else { 631 gre_hlen = tunnel->hlen; 632 fl6->daddr = tunnel->parms.raddr; 633 } 634 635 if (!fl6->flowi6_mark) 636 dst = ip6_tnl_dst_check(tunnel); 637 638 if (!dst) { 639 ndst = ip6_route_output(net, NULL, fl6); 640 641 if (ndst->error) 642 goto tx_err_link_failure; 643 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); 644 if (IS_ERR(ndst)) { 645 err = PTR_ERR(ndst); 646 ndst = NULL; 647 goto tx_err_link_failure; 648 } 649 dst = ndst; 650 } 651 652 tdev = dst->dev; 653 654 if (tdev == dev) { 655 stats->collisions++; 656 net_warn_ratelimited("%s: Local routing loop detected!\n", 657 tunnel->parms.name); 658 goto tx_err_dst_release; 659 } 660 661 mtu = dst_mtu(dst) - sizeof(*ipv6h); 662 if (encap_limit >= 0) { 663 max_headroom += 8; 664 mtu -= 8; 665 } 666 if (mtu < IPV6_MIN_MTU) 667 mtu = IPV6_MIN_MTU; 668 if (skb_dst(skb)) 669 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); 670 if (skb->len > mtu) { 671 *pmtu = mtu; 672 err = -EMSGSIZE; 673 goto tx_err_dst_release; 674 } 675 676 if (tunnel->err_count > 0) { 677 if (time_before(jiffies, 678 tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { 679 tunnel->err_count--; 680 681 dst_link_failure(skb); 682 } else 683 tunnel->err_count = 0; 684 } 685 686 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); 687 688 max_headroom += LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; 689 690 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 691 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 692 new_skb = skb_realloc_headroom(skb, max_headroom); 693 if (max_headroom > dev->needed_headroom) 694 dev->needed_headroom = max_headroom; 695 if (!new_skb) 696 goto tx_err_dst_release; 697 698 if (skb->sk) 699 skb_set_owner_w(new_skb, skb->sk); 700 consume_skb(skb); 701 skb = new_skb; 702 } 703 704 if (fl6->flowi6_mark) { 705 skb_dst_set(skb, dst); 706 ndst = NULL; 707 } else { 708 skb_dst_set_noref(skb, dst); 709 } 710 711 proto = NEXTHDR_GRE; 712 if (encap_limit >= 0) { 713 init_tel_txopt(&opt, encap_limit); 714 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); 715 } 716 717 if (likely(!skb->encapsulation)) { 718 skb_reset_inner_headers(skb); 719 skb->encapsulation = 1; 720 } 721 722 skb_push(skb, gre_hlen); 723 skb_reset_network_header(skb); 724 skb_set_transport_header(skb, sizeof(*ipv6h)); 725 726 /* 727 * Push down and install the IP header. 728 */ 729 ipv6h = ipv6_hdr(skb); 730 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), 731 ip6_make_flowlabel(net, skb, fl6->flowlabel, false)); 732 ipv6h->hop_limit = tunnel->parms.hop_limit; 733 ipv6h->nexthdr = proto; 734 ipv6h->saddr = fl6->saddr; 735 ipv6h->daddr = fl6->daddr; 736 737 ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; 738 protocol = (dev->type == ARPHRD_ETHER) ? 739 htons(ETH_P_TEB) : skb->protocol; 740 ((__be16 *)(ipv6h + 1))[1] = protocol; 741 742 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { 743 __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); 744 745 if (tunnel->parms.o_flags&GRE_SEQ) { 746 ++tunnel->o_seqno; 747 *ptr = htonl(tunnel->o_seqno); 748 ptr--; 749 } 750 if (tunnel->parms.o_flags&GRE_KEY) { 751 *ptr = tunnel->parms.o_key; 752 ptr--; 753 } 754 if (tunnel->parms.o_flags&GRE_CSUM) { 755 *ptr = 0; 756 *(__sum16 *)ptr = ip_compute_csum((void *)(ipv6h+1), 757 skb->len - sizeof(struct ipv6hdr)); 758 } 759 } 760 761 skb_set_inner_protocol(skb, protocol); 762 763 ip6tunnel_xmit(skb, dev); 764 if (ndst) 765 ip6_tnl_dst_store(tunnel, ndst); 766 return 0; 767 tx_err_link_failure: 768 stats->tx_carrier_errors++; 769 dst_link_failure(skb); 770 tx_err_dst_release: 771 dst_release(ndst); 772 return err; 773 } 774 775 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 776 { 777 struct ip6_tnl *t = netdev_priv(dev); 778 const struct iphdr *iph = ip_hdr(skb); 779 int encap_limit = -1; 780 struct flowi6 fl6; 781 __u8 dsfield; 782 __u32 mtu; 783 int err; 784 785 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 786 encap_limit = t->parms.encap_limit; 787 788 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 789 fl6.flowi6_proto = IPPROTO_GRE; 790 791 dsfield = ipv4_get_dsfield(iph); 792 793 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 794 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) 795 & IPV6_TCLASS_MASK; 796 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 797 fl6.flowi6_mark = skb->mark; 798 799 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 800 if (err != 0) { 801 /* XXX: send ICMP error even if DF is not set. */ 802 if (err == -EMSGSIZE) 803 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 804 htonl(mtu)); 805 return -1; 806 } 807 808 return 0; 809 } 810 811 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 812 { 813 struct ip6_tnl *t = netdev_priv(dev); 814 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 815 int encap_limit = -1; 816 __u16 offset; 817 struct flowi6 fl6; 818 __u8 dsfield; 819 __u32 mtu; 820 int err; 821 822 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 823 return -1; 824 825 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 826 if (offset > 0) { 827 struct ipv6_tlv_tnl_enc_lim *tel; 828 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 829 if (tel->encap_limit == 0) { 830 icmpv6_send(skb, ICMPV6_PARAMPROB, 831 ICMPV6_HDR_FIELD, offset + 2); 832 return -1; 833 } 834 encap_limit = tel->encap_limit - 1; 835 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 836 encap_limit = t->parms.encap_limit; 837 838 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 839 fl6.flowi6_proto = IPPROTO_GRE; 840 841 dsfield = ipv6_get_dsfield(ipv6h); 842 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 843 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); 844 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 845 fl6.flowlabel |= ip6_flowlabel(ipv6h); 846 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 847 fl6.flowi6_mark = skb->mark; 848 849 err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); 850 if (err != 0) { 851 if (err == -EMSGSIZE) 852 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 853 return -1; 854 } 855 856 return 0; 857 } 858 859 /** 860 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 861 * @t: the outgoing tunnel device 862 * @hdr: IPv6 header from the incoming packet 863 * 864 * Description: 865 * Avoid trivial tunneling loop by checking that tunnel exit-point 866 * doesn't match source of incoming packet. 867 * 868 * Return: 869 * 1 if conflict, 870 * 0 else 871 **/ 872 873 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 874 const struct ipv6hdr *hdr) 875 { 876 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 877 } 878 879 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 880 { 881 struct ip6_tnl *t = netdev_priv(dev); 882 int encap_limit = -1; 883 struct flowi6 fl6; 884 __u32 mtu; 885 int err; 886 887 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 888 encap_limit = t->parms.encap_limit; 889 890 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 891 fl6.flowi6_proto = skb->protocol; 892 893 err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); 894 895 return err; 896 } 897 898 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 899 struct net_device *dev) 900 { 901 struct ip6_tnl *t = netdev_priv(dev); 902 struct net_device_stats *stats = &t->dev->stats; 903 int ret; 904 905 if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr)) 906 goto tx_err; 907 908 switch (skb->protocol) { 909 case htons(ETH_P_IP): 910 ret = ip6gre_xmit_ipv4(skb, dev); 911 break; 912 case htons(ETH_P_IPV6): 913 ret = ip6gre_xmit_ipv6(skb, dev); 914 break; 915 default: 916 ret = ip6gre_xmit_other(skb, dev); 917 break; 918 } 919 920 if (ret < 0) 921 goto tx_err; 922 923 return NETDEV_TX_OK; 924 925 tx_err: 926 stats->tx_errors++; 927 stats->tx_dropped++; 928 kfree_skb(skb); 929 return NETDEV_TX_OK; 930 } 931 932 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 933 { 934 struct net_device *dev = t->dev; 935 struct __ip6_tnl_parm *p = &t->parms; 936 struct flowi6 *fl6 = &t->fl.u.ip6; 937 int addend = sizeof(struct ipv6hdr) + 4; 938 939 if (dev->type != ARPHRD_ETHER) { 940 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 941 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 942 } 943 944 /* Set up flowi template */ 945 fl6->saddr = p->laddr; 946 fl6->daddr = p->raddr; 947 fl6->flowi6_oif = p->link; 948 fl6->flowlabel = 0; 949 950 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 951 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 952 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 953 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 954 955 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 956 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 957 958 if (p->flags&IP6_TNL_F_CAP_XMIT && 959 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 960 dev->flags |= IFF_POINTOPOINT; 961 else 962 dev->flags &= ~IFF_POINTOPOINT; 963 964 /* Precalculate GRE options length */ 965 if (t->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) { 966 if (t->parms.o_flags&GRE_CSUM) 967 addend += 4; 968 if (t->parms.o_flags&GRE_KEY) 969 addend += 4; 970 if (t->parms.o_flags&GRE_SEQ) 971 addend += 4; 972 } 973 t->hlen = addend; 974 975 if (p->flags & IP6_TNL_F_CAP_XMIT) { 976 int strict = (ipv6_addr_type(&p->raddr) & 977 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 978 979 struct rt6_info *rt = rt6_lookup(t->net, 980 &p->raddr, &p->laddr, 981 p->link, strict); 982 983 if (rt == NULL) 984 return; 985 986 if (rt->dst.dev) { 987 dev->hard_header_len = rt->dst.dev->hard_header_len + addend; 988 989 if (set_mtu) { 990 dev->mtu = rt->dst.dev->mtu - addend; 991 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 992 dev->mtu -= 8; 993 994 if (dev->mtu < IPV6_MIN_MTU) 995 dev->mtu = IPV6_MIN_MTU; 996 } 997 } 998 ip6_rt_put(rt); 999 } 1000 } 1001 1002 static int ip6gre_tnl_change(struct ip6_tnl *t, 1003 const struct __ip6_tnl_parm *p, int set_mtu) 1004 { 1005 t->parms.laddr = p->laddr; 1006 t->parms.raddr = p->raddr; 1007 t->parms.flags = p->flags; 1008 t->parms.hop_limit = p->hop_limit; 1009 t->parms.encap_limit = p->encap_limit; 1010 t->parms.flowinfo = p->flowinfo; 1011 t->parms.link = p->link; 1012 t->parms.proto = p->proto; 1013 t->parms.i_key = p->i_key; 1014 t->parms.o_key = p->o_key; 1015 t->parms.i_flags = p->i_flags; 1016 t->parms.o_flags = p->o_flags; 1017 ip6_tnl_dst_reset(t); 1018 ip6gre_tnl_link_config(t, set_mtu); 1019 return 0; 1020 } 1021 1022 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 1023 const struct ip6_tnl_parm2 *u) 1024 { 1025 p->laddr = u->laddr; 1026 p->raddr = u->raddr; 1027 p->flags = u->flags; 1028 p->hop_limit = u->hop_limit; 1029 p->encap_limit = u->encap_limit; 1030 p->flowinfo = u->flowinfo; 1031 p->link = u->link; 1032 p->i_key = u->i_key; 1033 p->o_key = u->o_key; 1034 p->i_flags = u->i_flags; 1035 p->o_flags = u->o_flags; 1036 memcpy(p->name, u->name, sizeof(u->name)); 1037 } 1038 1039 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 1040 const struct __ip6_tnl_parm *p) 1041 { 1042 u->proto = IPPROTO_GRE; 1043 u->laddr = p->laddr; 1044 u->raddr = p->raddr; 1045 u->flags = p->flags; 1046 u->hop_limit = p->hop_limit; 1047 u->encap_limit = p->encap_limit; 1048 u->flowinfo = p->flowinfo; 1049 u->link = p->link; 1050 u->i_key = p->i_key; 1051 u->o_key = p->o_key; 1052 u->i_flags = p->i_flags; 1053 u->o_flags = p->o_flags; 1054 memcpy(u->name, p->name, sizeof(u->name)); 1055 } 1056 1057 static int ip6gre_tunnel_ioctl(struct net_device *dev, 1058 struct ifreq *ifr, int cmd) 1059 { 1060 int err = 0; 1061 struct ip6_tnl_parm2 p; 1062 struct __ip6_tnl_parm p1; 1063 struct ip6_tnl *t = netdev_priv(dev); 1064 struct net *net = t->net; 1065 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1066 1067 switch (cmd) { 1068 case SIOCGETTUNNEL: 1069 if (dev == ign->fb_tunnel_dev) { 1070 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 1071 err = -EFAULT; 1072 break; 1073 } 1074 ip6gre_tnl_parm_from_user(&p1, &p); 1075 t = ip6gre_tunnel_locate(net, &p1, 0); 1076 if (t == NULL) 1077 t = netdev_priv(dev); 1078 } 1079 memset(&p, 0, sizeof(p)); 1080 ip6gre_tnl_parm_to_user(&p, &t->parms); 1081 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1082 err = -EFAULT; 1083 break; 1084 1085 case SIOCADDTUNNEL: 1086 case SIOCCHGTUNNEL: 1087 err = -EPERM; 1088 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1089 goto done; 1090 1091 err = -EFAULT; 1092 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1093 goto done; 1094 1095 err = -EINVAL; 1096 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 1097 goto done; 1098 1099 if (!(p.i_flags&GRE_KEY)) 1100 p.i_key = 0; 1101 if (!(p.o_flags&GRE_KEY)) 1102 p.o_key = 0; 1103 1104 ip6gre_tnl_parm_from_user(&p1, &p); 1105 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 1106 1107 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 1108 if (t != NULL) { 1109 if (t->dev != dev) { 1110 err = -EEXIST; 1111 break; 1112 } 1113 } else { 1114 t = netdev_priv(dev); 1115 1116 ip6gre_tunnel_unlink(ign, t); 1117 synchronize_net(); 1118 ip6gre_tnl_change(t, &p1, 1); 1119 ip6gre_tunnel_link(ign, t); 1120 netdev_state_change(dev); 1121 } 1122 } 1123 1124 if (t) { 1125 err = 0; 1126 1127 memset(&p, 0, sizeof(p)); 1128 ip6gre_tnl_parm_to_user(&p, &t->parms); 1129 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 1130 err = -EFAULT; 1131 } else 1132 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 1133 break; 1134 1135 case SIOCDELTUNNEL: 1136 err = -EPERM; 1137 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 1138 goto done; 1139 1140 if (dev == ign->fb_tunnel_dev) { 1141 err = -EFAULT; 1142 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 1143 goto done; 1144 err = -ENOENT; 1145 ip6gre_tnl_parm_from_user(&p1, &p); 1146 t = ip6gre_tunnel_locate(net, &p1, 0); 1147 if (t == NULL) 1148 goto done; 1149 err = -EPERM; 1150 if (t == netdev_priv(ign->fb_tunnel_dev)) 1151 goto done; 1152 dev = t->dev; 1153 } 1154 unregister_netdevice(dev); 1155 err = 0; 1156 break; 1157 1158 default: 1159 err = -EINVAL; 1160 } 1161 1162 done: 1163 return err; 1164 } 1165 1166 static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) 1167 { 1168 if (new_mtu < 68 || 1169 new_mtu > 0xFFF8 - dev->hard_header_len) 1170 return -EINVAL; 1171 dev->mtu = new_mtu; 1172 return 0; 1173 } 1174 1175 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 1176 unsigned short type, 1177 const void *daddr, const void *saddr, unsigned int len) 1178 { 1179 struct ip6_tnl *t = netdev_priv(dev); 1180 struct ipv6hdr *ipv6h = (struct ipv6hdr *)skb_push(skb, t->hlen); 1181 __be16 *p = (__be16 *)(ipv6h+1); 1182 1183 ip6_flow_hdr(ipv6h, 0, 1184 ip6_make_flowlabel(dev_net(dev), skb, 1185 t->fl.u.ip6.flowlabel, false)); 1186 ipv6h->hop_limit = t->parms.hop_limit; 1187 ipv6h->nexthdr = NEXTHDR_GRE; 1188 ipv6h->saddr = t->parms.laddr; 1189 ipv6h->daddr = t->parms.raddr; 1190 1191 p[0] = t->parms.o_flags; 1192 p[1] = htons(type); 1193 1194 /* 1195 * Set the source hardware address. 1196 */ 1197 1198 if (saddr) 1199 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 1200 if (daddr) 1201 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 1202 if (!ipv6_addr_any(&ipv6h->daddr)) 1203 return t->hlen; 1204 1205 return -t->hlen; 1206 } 1207 1208 static const struct header_ops ip6gre_header_ops = { 1209 .create = ip6gre_header, 1210 }; 1211 1212 static const struct net_device_ops ip6gre_netdev_ops = { 1213 .ndo_init = ip6gre_tunnel_init, 1214 .ndo_uninit = ip6gre_tunnel_uninit, 1215 .ndo_start_xmit = ip6gre_tunnel_xmit, 1216 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 1217 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1218 .ndo_get_stats64 = ip_tunnel_get_stats64, 1219 }; 1220 1221 static void ip6gre_dev_free(struct net_device *dev) 1222 { 1223 free_percpu(dev->tstats); 1224 free_netdev(dev); 1225 } 1226 1227 static void ip6gre_tunnel_setup(struct net_device *dev) 1228 { 1229 struct ip6_tnl *t; 1230 1231 dev->netdev_ops = &ip6gre_netdev_ops; 1232 dev->destructor = ip6gre_dev_free; 1233 1234 dev->type = ARPHRD_IP6GRE; 1235 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; 1236 dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; 1237 t = netdev_priv(dev); 1238 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1239 dev->mtu -= 8; 1240 dev->flags |= IFF_NOARP; 1241 dev->iflink = 0; 1242 dev->addr_len = sizeof(struct in6_addr); 1243 netif_keep_dst(dev); 1244 } 1245 1246 static int ip6gre_tunnel_init(struct net_device *dev) 1247 { 1248 struct ip6_tnl *tunnel; 1249 int i; 1250 1251 tunnel = netdev_priv(dev); 1252 1253 tunnel->dev = dev; 1254 tunnel->net = dev_net(dev); 1255 strcpy(tunnel->parms.name, dev->name); 1256 1257 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1258 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1259 1260 if (ipv6_addr_any(&tunnel->parms.raddr)) 1261 dev->header_ops = &ip6gre_header_ops; 1262 1263 dev->tstats = alloc_percpu(struct pcpu_sw_netstats); 1264 if (!dev->tstats) 1265 return -ENOMEM; 1266 1267 for_each_possible_cpu(i) { 1268 struct pcpu_sw_netstats *ip6gre_tunnel_stats; 1269 ip6gre_tunnel_stats = per_cpu_ptr(dev->tstats, i); 1270 u64_stats_init(&ip6gre_tunnel_stats->syncp); 1271 } 1272 1273 dev->iflink = tunnel->parms.link; 1274 1275 return 0; 1276 } 1277 1278 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1279 { 1280 struct ip6_tnl *tunnel = netdev_priv(dev); 1281 1282 tunnel->dev = dev; 1283 tunnel->net = dev_net(dev); 1284 strcpy(tunnel->parms.name, dev->name); 1285 1286 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1287 1288 dev_hold(dev); 1289 } 1290 1291 1292 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1293 .handler = ip6gre_rcv, 1294 .err_handler = ip6gre_err, 1295 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1296 }; 1297 1298 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 1299 { 1300 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1301 struct net_device *dev, *aux; 1302 int prio; 1303 1304 for_each_netdev_safe(net, dev, aux) 1305 if (dev->rtnl_link_ops == &ip6gre_link_ops || 1306 dev->rtnl_link_ops == &ip6gre_tap_ops) 1307 unregister_netdevice_queue(dev, head); 1308 1309 for (prio = 0; prio < 4; prio++) { 1310 int h; 1311 for (h = 0; h < HASH_SIZE; h++) { 1312 struct ip6_tnl *t; 1313 1314 t = rtnl_dereference(ign->tunnels[prio][h]); 1315 1316 while (t != NULL) { 1317 /* If dev is in the same netns, it has already 1318 * been added to the list by the previous loop. 1319 */ 1320 if (!net_eq(dev_net(t->dev), net)) 1321 unregister_netdevice_queue(t->dev, 1322 head); 1323 t = rtnl_dereference(t->next); 1324 } 1325 } 1326 } 1327 } 1328 1329 static int __net_init ip6gre_init_net(struct net *net) 1330 { 1331 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1332 int err; 1333 1334 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1335 NET_NAME_UNKNOWN, 1336 ip6gre_tunnel_setup); 1337 if (!ign->fb_tunnel_dev) { 1338 err = -ENOMEM; 1339 goto err_alloc_dev; 1340 } 1341 dev_net_set(ign->fb_tunnel_dev, net); 1342 /* FB netdevice is special: we have one, and only one per netns. 1343 * Allowing to move it to another netns is clearly unsafe. 1344 */ 1345 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1346 1347 1348 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1349 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1350 1351 err = register_netdev(ign->fb_tunnel_dev); 1352 if (err) 1353 goto err_reg_dev; 1354 1355 rcu_assign_pointer(ign->tunnels_wc[0], 1356 netdev_priv(ign->fb_tunnel_dev)); 1357 return 0; 1358 1359 err_reg_dev: 1360 ip6gre_dev_free(ign->fb_tunnel_dev); 1361 err_alloc_dev: 1362 return err; 1363 } 1364 1365 static void __net_exit ip6gre_exit_net(struct net *net) 1366 { 1367 LIST_HEAD(list); 1368 1369 rtnl_lock(); 1370 ip6gre_destroy_tunnels(net, &list); 1371 unregister_netdevice_many(&list); 1372 rtnl_unlock(); 1373 } 1374 1375 static struct pernet_operations ip6gre_net_ops = { 1376 .init = ip6gre_init_net, 1377 .exit = ip6gre_exit_net, 1378 .id = &ip6gre_net_id, 1379 .size = sizeof(struct ip6gre_net), 1380 }; 1381 1382 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) 1383 { 1384 __be16 flags; 1385 1386 if (!data) 1387 return 0; 1388 1389 flags = 0; 1390 if (data[IFLA_GRE_IFLAGS]) 1391 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1392 if (data[IFLA_GRE_OFLAGS]) 1393 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1394 if (flags & (GRE_VERSION|GRE_ROUTING)) 1395 return -EINVAL; 1396 1397 return 0; 1398 } 1399 1400 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) 1401 { 1402 struct in6_addr daddr; 1403 1404 if (tb[IFLA_ADDRESS]) { 1405 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1406 return -EINVAL; 1407 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1408 return -EADDRNOTAVAIL; 1409 } 1410 1411 if (!data) 1412 goto out; 1413 1414 if (data[IFLA_GRE_REMOTE]) { 1415 nla_memcpy(&daddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1416 if (ipv6_addr_any(&daddr)) 1417 return -EINVAL; 1418 } 1419 1420 out: 1421 return ip6gre_tunnel_validate(tb, data); 1422 } 1423 1424 1425 static void ip6gre_netlink_parms(struct nlattr *data[], 1426 struct __ip6_tnl_parm *parms) 1427 { 1428 memset(parms, 0, sizeof(*parms)); 1429 1430 if (!data) 1431 return; 1432 1433 if (data[IFLA_GRE_LINK]) 1434 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1435 1436 if (data[IFLA_GRE_IFLAGS]) 1437 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]); 1438 1439 if (data[IFLA_GRE_OFLAGS]) 1440 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]); 1441 1442 if (data[IFLA_GRE_IKEY]) 1443 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1444 1445 if (data[IFLA_GRE_OKEY]) 1446 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1447 1448 if (data[IFLA_GRE_LOCAL]) 1449 nla_memcpy(&parms->laddr, data[IFLA_GRE_LOCAL], sizeof(struct in6_addr)); 1450 1451 if (data[IFLA_GRE_REMOTE]) 1452 nla_memcpy(&parms->raddr, data[IFLA_GRE_REMOTE], sizeof(struct in6_addr)); 1453 1454 if (data[IFLA_GRE_TTL]) 1455 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1456 1457 if (data[IFLA_GRE_ENCAP_LIMIT]) 1458 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1459 1460 if (data[IFLA_GRE_FLOWINFO]) 1461 parms->flowinfo = nla_get_u32(data[IFLA_GRE_FLOWINFO]); 1462 1463 if (data[IFLA_GRE_FLAGS]) 1464 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1465 } 1466 1467 static int ip6gre_tap_init(struct net_device *dev) 1468 { 1469 struct ip6_tnl *tunnel; 1470 1471 tunnel = netdev_priv(dev); 1472 1473 tunnel->dev = dev; 1474 tunnel->net = dev_net(dev); 1475 strcpy(tunnel->parms.name, dev->name); 1476 1477 ip6gre_tnl_link_config(tunnel, 1); 1478 1479 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1480 if (!dev->tstats) 1481 return -ENOMEM; 1482 1483 dev->iflink = tunnel->parms.link; 1484 1485 return 0; 1486 } 1487 1488 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1489 .ndo_init = ip6gre_tap_init, 1490 .ndo_uninit = ip6gre_tunnel_uninit, 1491 .ndo_start_xmit = ip6gre_tunnel_xmit, 1492 .ndo_set_mac_address = eth_mac_addr, 1493 .ndo_validate_addr = eth_validate_addr, 1494 .ndo_change_mtu = ip6gre_tunnel_change_mtu, 1495 .ndo_get_stats64 = ip_tunnel_get_stats64, 1496 }; 1497 1498 static void ip6gre_tap_setup(struct net_device *dev) 1499 { 1500 1501 ether_setup(dev); 1502 1503 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1504 dev->destructor = ip6gre_dev_free; 1505 1506 dev->iflink = 0; 1507 dev->features |= NETIF_F_NETNS_LOCAL; 1508 } 1509 1510 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1511 struct nlattr *tb[], struct nlattr *data[]) 1512 { 1513 struct ip6_tnl *nt; 1514 struct net *net = dev_net(dev); 1515 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1516 int err; 1517 1518 nt = netdev_priv(dev); 1519 ip6gre_netlink_parms(data, &nt->parms); 1520 1521 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1522 return -EEXIST; 1523 1524 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1525 eth_hw_addr_random(dev); 1526 1527 nt->dev = dev; 1528 nt->net = dev_net(dev); 1529 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1530 1531 /* Can use a lockless transmit, unless we generate output sequences */ 1532 if (!(nt->parms.o_flags & GRE_SEQ)) 1533 dev->features |= NETIF_F_LLTX; 1534 1535 err = register_netdevice(dev); 1536 if (err) 1537 goto out; 1538 1539 dev_hold(dev); 1540 ip6gre_tunnel_link(ign, nt); 1541 1542 out: 1543 return err; 1544 } 1545 1546 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1547 struct nlattr *data[]) 1548 { 1549 struct ip6_tnl *t, *nt = netdev_priv(dev); 1550 struct net *net = nt->net; 1551 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1552 struct __ip6_tnl_parm p; 1553 1554 if (dev == ign->fb_tunnel_dev) 1555 return -EINVAL; 1556 1557 ip6gre_netlink_parms(data, &p); 1558 1559 t = ip6gre_tunnel_locate(net, &p, 0); 1560 1561 if (t) { 1562 if (t->dev != dev) 1563 return -EEXIST; 1564 } else { 1565 t = nt; 1566 1567 ip6gre_tunnel_unlink(ign, t); 1568 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1569 ip6gre_tunnel_link(ign, t); 1570 netdev_state_change(dev); 1571 } 1572 1573 return 0; 1574 } 1575 1576 static void ip6gre_dellink(struct net_device *dev, struct list_head *head) 1577 { 1578 struct net *net = dev_net(dev); 1579 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1580 1581 if (dev != ign->fb_tunnel_dev) 1582 unregister_netdevice_queue(dev, head); 1583 } 1584 1585 static size_t ip6gre_get_size(const struct net_device *dev) 1586 { 1587 return 1588 /* IFLA_GRE_LINK */ 1589 nla_total_size(4) + 1590 /* IFLA_GRE_IFLAGS */ 1591 nla_total_size(2) + 1592 /* IFLA_GRE_OFLAGS */ 1593 nla_total_size(2) + 1594 /* IFLA_GRE_IKEY */ 1595 nla_total_size(4) + 1596 /* IFLA_GRE_OKEY */ 1597 nla_total_size(4) + 1598 /* IFLA_GRE_LOCAL */ 1599 nla_total_size(sizeof(struct in6_addr)) + 1600 /* IFLA_GRE_REMOTE */ 1601 nla_total_size(sizeof(struct in6_addr)) + 1602 /* IFLA_GRE_TTL */ 1603 nla_total_size(1) + 1604 /* IFLA_GRE_TOS */ 1605 nla_total_size(1) + 1606 /* IFLA_GRE_ENCAP_LIMIT */ 1607 nla_total_size(1) + 1608 /* IFLA_GRE_FLOWINFO */ 1609 nla_total_size(4) + 1610 /* IFLA_GRE_FLAGS */ 1611 nla_total_size(4) + 1612 0; 1613 } 1614 1615 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1616 { 1617 struct ip6_tnl *t = netdev_priv(dev); 1618 struct __ip6_tnl_parm *p = &t->parms; 1619 1620 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1621 nla_put_be16(skb, IFLA_GRE_IFLAGS, p->i_flags) || 1622 nla_put_be16(skb, IFLA_GRE_OFLAGS, p->o_flags) || 1623 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1624 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1625 nla_put(skb, IFLA_GRE_LOCAL, sizeof(struct in6_addr), &p->laddr) || 1626 nla_put(skb, IFLA_GRE_REMOTE, sizeof(struct in6_addr), &p->raddr) || 1627 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1628 /*nla_put_u8(skb, IFLA_GRE_TOS, t->priority) ||*/ 1629 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1630 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1631 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags)) 1632 goto nla_put_failure; 1633 return 0; 1634 1635 nla_put_failure: 1636 return -EMSGSIZE; 1637 } 1638 1639 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1640 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1641 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1642 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1643 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1644 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1645 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1646 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1647 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1648 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1649 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1650 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1651 }; 1652 1653 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1654 .kind = "ip6gre", 1655 .maxtype = IFLA_GRE_MAX, 1656 .policy = ip6gre_policy, 1657 .priv_size = sizeof(struct ip6_tnl), 1658 .setup = ip6gre_tunnel_setup, 1659 .validate = ip6gre_tunnel_validate, 1660 .newlink = ip6gre_newlink, 1661 .changelink = ip6gre_changelink, 1662 .dellink = ip6gre_dellink, 1663 .get_size = ip6gre_get_size, 1664 .fill_info = ip6gre_fill_info, 1665 }; 1666 1667 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1668 .kind = "ip6gretap", 1669 .maxtype = IFLA_GRE_MAX, 1670 .policy = ip6gre_policy, 1671 .priv_size = sizeof(struct ip6_tnl), 1672 .setup = ip6gre_tap_setup, 1673 .validate = ip6gre_tap_validate, 1674 .newlink = ip6gre_newlink, 1675 .changelink = ip6gre_changelink, 1676 .get_size = ip6gre_get_size, 1677 .fill_info = ip6gre_fill_info, 1678 }; 1679 1680 /* 1681 * And now the modules code and kernel interface. 1682 */ 1683 1684 static int __init ip6gre_init(void) 1685 { 1686 int err; 1687 1688 pr_info("GRE over IPv6 tunneling driver\n"); 1689 1690 err = register_pernet_device(&ip6gre_net_ops); 1691 if (err < 0) 1692 return err; 1693 1694 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1695 if (err < 0) { 1696 pr_info("%s: can't add protocol\n", __func__); 1697 goto add_proto_failed; 1698 } 1699 1700 err = rtnl_link_register(&ip6gre_link_ops); 1701 if (err < 0) 1702 goto rtnl_link_failed; 1703 1704 err = rtnl_link_register(&ip6gre_tap_ops); 1705 if (err < 0) 1706 goto tap_ops_failed; 1707 1708 out: 1709 return err; 1710 1711 tap_ops_failed: 1712 rtnl_link_unregister(&ip6gre_link_ops); 1713 rtnl_link_failed: 1714 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1715 add_proto_failed: 1716 unregister_pernet_device(&ip6gre_net_ops); 1717 goto out; 1718 } 1719 1720 static void __exit ip6gre_fini(void) 1721 { 1722 rtnl_link_unregister(&ip6gre_tap_ops); 1723 rtnl_link_unregister(&ip6gre_link_ops); 1724 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1725 unregister_pernet_device(&ip6gre_net_ops); 1726 } 1727 1728 module_init(ip6gre_init); 1729 module_exit(ip6gre_fini); 1730 MODULE_LICENSE("GPL"); 1731 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1732 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1733 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1734 MODULE_ALIAS_RTNL_LINK("ip6gretap"); 1735 MODULE_ALIAS_NETDEV("ip6gre0"); 1736