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/init.h> 28 #include <linux/in6.h> 29 #include <linux/inetdevice.h> 30 #include <linux/igmp.h> 31 #include <linux/netfilter_ipv4.h> 32 #include <linux/etherdevice.h> 33 #include <linux/if_ether.h> 34 #include <linux/hash.h> 35 #include <linux/if_tunnel.h> 36 #include <linux/ip6_tunnel.h> 37 38 #include <net/sock.h> 39 #include <net/ip.h> 40 #include <net/ip_tunnels.h> 41 #include <net/icmp.h> 42 #include <net/protocol.h> 43 #include <net/addrconf.h> 44 #include <net/arp.h> 45 #include <net/checksum.h> 46 #include <net/dsfield.h> 47 #include <net/inet_ecn.h> 48 #include <net/xfrm.h> 49 #include <net/net_namespace.h> 50 #include <net/netns/generic.h> 51 #include <net/rtnetlink.h> 52 53 #include <net/ipv6.h> 54 #include <net/ip6_fib.h> 55 #include <net/ip6_route.h> 56 #include <net/ip6_tunnel.h> 57 #include <net/gre.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 IP6_GRE_HASH_SIZE_SHIFT 5 65 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT) 66 67 static unsigned int ip6gre_net_id __read_mostly; 68 struct ip6gre_net { 69 struct ip6_tnl __rcu *tunnels[4][IP6_GRE_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))&(IP6_GRE_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, IP6_GRE_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) 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 & TUNNEL_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 dst_cache_reset(&t->dst_cache); 365 dev_put(dev); 366 } 367 368 369 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 370 u8 type, u8 code, int offset, __be32 info) 371 { 372 const struct gre_base_hdr *greh; 373 const struct ipv6hdr *ipv6h; 374 int grehlen = sizeof(*greh); 375 struct ip6_tnl *t; 376 int key_off = 0; 377 __be16 flags; 378 __be32 key; 379 380 if (!pskb_may_pull(skb, offset + grehlen)) 381 return; 382 greh = (const struct gre_base_hdr *)(skb->data + offset); 383 flags = greh->flags; 384 if (flags & (GRE_VERSION | GRE_ROUTING)) 385 return; 386 if (flags & GRE_CSUM) 387 grehlen += 4; 388 if (flags & GRE_KEY) { 389 key_off = grehlen + offset; 390 grehlen += 4; 391 } 392 393 if (!pskb_may_pull(skb, offset + grehlen)) 394 return; 395 ipv6h = (const struct ipv6hdr *)skb->data; 396 greh = (const struct gre_base_hdr *)(skb->data + offset); 397 key = key_off ? *(__be32 *)(skb->data + key_off) : 0; 398 399 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 400 key, greh->protocol); 401 if (!t) 402 return; 403 404 switch (type) { 405 __u32 teli; 406 struct ipv6_tlv_tnl_enc_lim *tel; 407 __u32 mtu; 408 case ICMPV6_DEST_UNREACH: 409 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 410 t->parms.name); 411 if (code != ICMPV6_PORT_UNREACH) 412 break; 413 return; 414 case ICMPV6_TIME_EXCEED: 415 if (code == ICMPV6_EXC_HOPLIMIT) { 416 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 417 t->parms.name); 418 break; 419 } 420 return; 421 case ICMPV6_PARAMPROB: 422 teli = 0; 423 if (code == ICMPV6_HDR_FIELD) 424 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 425 426 if (teli && teli == be32_to_cpu(info) - 2) { 427 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 428 if (tel->encap_limit == 0) { 429 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 430 t->parms.name); 431 } 432 } else { 433 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 434 t->parms.name); 435 } 436 return; 437 case ICMPV6_PKT_TOOBIG: 438 mtu = be32_to_cpu(info) - offset - t->tun_hlen; 439 if (t->dev->type == ARPHRD_ETHER) 440 mtu -= ETH_HLEN; 441 if (mtu < IPV6_MIN_MTU) 442 mtu = IPV6_MIN_MTU; 443 t->dev->mtu = mtu; 444 return; 445 } 446 447 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 448 t->err_count++; 449 else 450 t->err_count = 1; 451 t->err_time = jiffies; 452 } 453 454 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi) 455 { 456 const struct ipv6hdr *ipv6h; 457 struct ip6_tnl *tunnel; 458 459 ipv6h = ipv6_hdr(skb); 460 tunnel = ip6gre_tunnel_lookup(skb->dev, 461 &ipv6h->saddr, &ipv6h->daddr, tpi->key, 462 tpi->proto); 463 if (tunnel) { 464 ip6_tnl_rcv(tunnel, skb, tpi, NULL, false); 465 466 return PACKET_RCVD; 467 } 468 469 return PACKET_REJECT; 470 } 471 472 static int gre_rcv(struct sk_buff *skb) 473 { 474 struct tnl_ptk_info tpi; 475 bool csum_err = false; 476 int hdr_len; 477 478 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0); 479 if (hdr_len < 0) 480 goto drop; 481 482 if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false)) 483 goto drop; 484 485 if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD) 486 return 0; 487 488 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 489 drop: 490 kfree_skb(skb); 491 return 0; 492 } 493 494 static int gre_handle_offloads(struct sk_buff *skb, bool csum) 495 { 496 return iptunnel_handle_offloads(skb, 497 csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); 498 } 499 500 static netdev_tx_t __gre6_xmit(struct sk_buff *skb, 501 struct net_device *dev, __u8 dsfield, 502 struct flowi6 *fl6, int encap_limit, 503 __u32 *pmtu, __be16 proto) 504 { 505 struct ip6_tnl *tunnel = netdev_priv(dev); 506 struct dst_entry *dst = skb_dst(skb); 507 __be16 protocol; 508 509 if (dev->type == ARPHRD_ETHER) 510 IPCB(skb)->flags = 0; 511 512 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) 513 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr; 514 else 515 fl6->daddr = tunnel->parms.raddr; 516 517 if (tunnel->parms.o_flags & TUNNEL_SEQ) 518 tunnel->o_seqno++; 519 520 /* Push GRE header. */ 521 protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto; 522 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags, 523 protocol, tunnel->parms.o_key, htonl(tunnel->o_seqno)); 524 525 /* TooBig packet may have updated dst->dev's mtu */ 526 if (dst && dst_mtu(dst) > dst->dev->mtu) 527 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu); 528 529 return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu, 530 NEXTHDR_GRE); 531 } 532 533 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 534 { 535 struct ip6_tnl *t = netdev_priv(dev); 536 const struct iphdr *iph = ip_hdr(skb); 537 int encap_limit = -1; 538 struct flowi6 fl6; 539 __u8 dsfield; 540 __u32 mtu; 541 int err; 542 543 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 544 545 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 546 encap_limit = t->parms.encap_limit; 547 548 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 549 550 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 551 dsfield = ipv4_get_dsfield(iph); 552 else 553 dsfield = ip6_tclass(t->parms.flowinfo); 554 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 555 fl6.flowi6_mark = skb->mark; 556 else 557 fl6.flowi6_mark = t->parms.fwmark; 558 559 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 560 561 err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); 562 if (err) 563 return -1; 564 565 err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 566 skb->protocol); 567 if (err != 0) { 568 /* XXX: send ICMP error even if DF is not set. */ 569 if (err == -EMSGSIZE) 570 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 571 htonl(mtu)); 572 return -1; 573 } 574 575 return 0; 576 } 577 578 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 579 { 580 struct ip6_tnl *t = netdev_priv(dev); 581 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 582 int encap_limit = -1; 583 __u16 offset; 584 struct flowi6 fl6; 585 __u8 dsfield; 586 __u32 mtu; 587 int err; 588 589 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 590 return -1; 591 592 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 593 /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */ 594 ipv6h = ipv6_hdr(skb); 595 596 if (offset > 0) { 597 struct ipv6_tlv_tnl_enc_lim *tel; 598 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 599 if (tel->encap_limit == 0) { 600 icmpv6_send(skb, ICMPV6_PARAMPROB, 601 ICMPV6_HDR_FIELD, offset + 2); 602 return -1; 603 } 604 encap_limit = tel->encap_limit - 1; 605 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 606 encap_limit = t->parms.encap_limit; 607 608 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 609 610 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 611 dsfield = ipv6_get_dsfield(ipv6h); 612 else 613 dsfield = ip6_tclass(t->parms.flowinfo); 614 615 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 616 fl6.flowlabel |= ip6_flowlabel(ipv6h); 617 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 618 fl6.flowi6_mark = skb->mark; 619 else 620 fl6.flowi6_mark = t->parms.fwmark; 621 622 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 623 624 if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM))) 625 return -1; 626 627 err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, 628 &mtu, skb->protocol); 629 if (err != 0) { 630 if (err == -EMSGSIZE) 631 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 632 return -1; 633 } 634 635 return 0; 636 } 637 638 /** 639 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 640 * @t: the outgoing tunnel device 641 * @hdr: IPv6 header from the incoming packet 642 * 643 * Description: 644 * Avoid trivial tunneling loop by checking that tunnel exit-point 645 * doesn't match source of incoming packet. 646 * 647 * Return: 648 * 1 if conflict, 649 * 0 else 650 **/ 651 652 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 653 const struct ipv6hdr *hdr) 654 { 655 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 656 } 657 658 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 659 { 660 struct ip6_tnl *t = netdev_priv(dev); 661 int encap_limit = -1; 662 struct flowi6 fl6; 663 __u32 mtu; 664 int err; 665 666 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 667 encap_limit = t->parms.encap_limit; 668 669 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 670 671 err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); 672 if (err) 673 return err; 674 675 err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol); 676 677 return err; 678 } 679 680 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 681 struct net_device *dev) 682 { 683 struct ip6_tnl *t = netdev_priv(dev); 684 struct net_device_stats *stats = &t->dev->stats; 685 int ret; 686 687 if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr)) 688 goto tx_err; 689 690 switch (skb->protocol) { 691 case htons(ETH_P_IP): 692 ret = ip6gre_xmit_ipv4(skb, dev); 693 break; 694 case htons(ETH_P_IPV6): 695 ret = ip6gre_xmit_ipv6(skb, dev); 696 break; 697 default: 698 ret = ip6gre_xmit_other(skb, dev); 699 break; 700 } 701 702 if (ret < 0) 703 goto tx_err; 704 705 return NETDEV_TX_OK; 706 707 tx_err: 708 stats->tx_errors++; 709 stats->tx_dropped++; 710 kfree_skb(skb); 711 return NETDEV_TX_OK; 712 } 713 714 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 715 { 716 struct net_device *dev = t->dev; 717 struct __ip6_tnl_parm *p = &t->parms; 718 struct flowi6 *fl6 = &t->fl.u.ip6; 719 int t_hlen; 720 721 if (dev->type != ARPHRD_ETHER) { 722 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 723 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 724 } 725 726 /* Set up flowi template */ 727 fl6->saddr = p->laddr; 728 fl6->daddr = p->raddr; 729 fl6->flowi6_oif = p->link; 730 fl6->flowlabel = 0; 731 fl6->flowi6_proto = IPPROTO_GRE; 732 733 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 734 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 735 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 736 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 737 738 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 739 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 740 741 if (p->flags&IP6_TNL_F_CAP_XMIT && 742 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 743 dev->flags |= IFF_POINTOPOINT; 744 else 745 dev->flags &= ~IFF_POINTOPOINT; 746 747 t->tun_hlen = gre_calc_hlen(t->parms.o_flags); 748 749 t->hlen = t->encap_hlen + t->tun_hlen; 750 751 t_hlen = t->hlen + sizeof(struct ipv6hdr); 752 753 if (p->flags & IP6_TNL_F_CAP_XMIT) { 754 int strict = (ipv6_addr_type(&p->raddr) & 755 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 756 757 struct rt6_info *rt = rt6_lookup(t->net, 758 &p->raddr, &p->laddr, 759 p->link, strict); 760 761 if (!rt) 762 return; 763 764 if (rt->dst.dev) { 765 dev->hard_header_len = rt->dst.dev->hard_header_len + 766 t_hlen; 767 768 if (set_mtu) { 769 dev->mtu = rt->dst.dev->mtu - t_hlen; 770 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 771 dev->mtu -= 8; 772 if (dev->type == ARPHRD_ETHER) 773 dev->mtu -= ETH_HLEN; 774 775 if (dev->mtu < IPV6_MIN_MTU) 776 dev->mtu = IPV6_MIN_MTU; 777 } 778 } 779 ip6_rt_put(rt); 780 } 781 } 782 783 static int ip6gre_tnl_change(struct ip6_tnl *t, 784 const struct __ip6_tnl_parm *p, int set_mtu) 785 { 786 t->parms.laddr = p->laddr; 787 t->parms.raddr = p->raddr; 788 t->parms.flags = p->flags; 789 t->parms.hop_limit = p->hop_limit; 790 t->parms.encap_limit = p->encap_limit; 791 t->parms.flowinfo = p->flowinfo; 792 t->parms.link = p->link; 793 t->parms.proto = p->proto; 794 t->parms.i_key = p->i_key; 795 t->parms.o_key = p->o_key; 796 t->parms.i_flags = p->i_flags; 797 t->parms.o_flags = p->o_flags; 798 t->parms.fwmark = p->fwmark; 799 dst_cache_reset(&t->dst_cache); 800 ip6gre_tnl_link_config(t, set_mtu); 801 return 0; 802 } 803 804 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 805 const struct ip6_tnl_parm2 *u) 806 { 807 p->laddr = u->laddr; 808 p->raddr = u->raddr; 809 p->flags = u->flags; 810 p->hop_limit = u->hop_limit; 811 p->encap_limit = u->encap_limit; 812 p->flowinfo = u->flowinfo; 813 p->link = u->link; 814 p->i_key = u->i_key; 815 p->o_key = u->o_key; 816 p->i_flags = gre_flags_to_tnl_flags(u->i_flags); 817 p->o_flags = gre_flags_to_tnl_flags(u->o_flags); 818 memcpy(p->name, u->name, sizeof(u->name)); 819 } 820 821 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 822 const struct __ip6_tnl_parm *p) 823 { 824 u->proto = IPPROTO_GRE; 825 u->laddr = p->laddr; 826 u->raddr = p->raddr; 827 u->flags = p->flags; 828 u->hop_limit = p->hop_limit; 829 u->encap_limit = p->encap_limit; 830 u->flowinfo = p->flowinfo; 831 u->link = p->link; 832 u->i_key = p->i_key; 833 u->o_key = p->o_key; 834 u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags); 835 u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags); 836 memcpy(u->name, p->name, sizeof(u->name)); 837 } 838 839 static int ip6gre_tunnel_ioctl(struct net_device *dev, 840 struct ifreq *ifr, int cmd) 841 { 842 int err = 0; 843 struct ip6_tnl_parm2 p; 844 struct __ip6_tnl_parm p1; 845 struct ip6_tnl *t = netdev_priv(dev); 846 struct net *net = t->net; 847 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 848 849 memset(&p1, 0, sizeof(p1)); 850 851 switch (cmd) { 852 case SIOCGETTUNNEL: 853 if (dev == ign->fb_tunnel_dev) { 854 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 855 err = -EFAULT; 856 break; 857 } 858 ip6gre_tnl_parm_from_user(&p1, &p); 859 t = ip6gre_tunnel_locate(net, &p1, 0); 860 if (!t) 861 t = netdev_priv(dev); 862 } 863 memset(&p, 0, sizeof(p)); 864 ip6gre_tnl_parm_to_user(&p, &t->parms); 865 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 866 err = -EFAULT; 867 break; 868 869 case SIOCADDTUNNEL: 870 case SIOCCHGTUNNEL: 871 err = -EPERM; 872 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 873 goto done; 874 875 err = -EFAULT; 876 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 877 goto done; 878 879 err = -EINVAL; 880 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 881 goto done; 882 883 if (!(p.i_flags&GRE_KEY)) 884 p.i_key = 0; 885 if (!(p.o_flags&GRE_KEY)) 886 p.o_key = 0; 887 888 ip6gre_tnl_parm_from_user(&p1, &p); 889 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 890 891 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 892 if (t) { 893 if (t->dev != dev) { 894 err = -EEXIST; 895 break; 896 } 897 } else { 898 t = netdev_priv(dev); 899 900 ip6gre_tunnel_unlink(ign, t); 901 synchronize_net(); 902 ip6gre_tnl_change(t, &p1, 1); 903 ip6gre_tunnel_link(ign, t); 904 netdev_state_change(dev); 905 } 906 } 907 908 if (t) { 909 err = 0; 910 911 memset(&p, 0, sizeof(p)); 912 ip6gre_tnl_parm_to_user(&p, &t->parms); 913 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 914 err = -EFAULT; 915 } else 916 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 917 break; 918 919 case SIOCDELTUNNEL: 920 err = -EPERM; 921 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 922 goto done; 923 924 if (dev == ign->fb_tunnel_dev) { 925 err = -EFAULT; 926 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 927 goto done; 928 err = -ENOENT; 929 ip6gre_tnl_parm_from_user(&p1, &p); 930 t = ip6gre_tunnel_locate(net, &p1, 0); 931 if (!t) 932 goto done; 933 err = -EPERM; 934 if (t == netdev_priv(ign->fb_tunnel_dev)) 935 goto done; 936 dev = t->dev; 937 } 938 unregister_netdevice(dev); 939 err = 0; 940 break; 941 942 default: 943 err = -EINVAL; 944 } 945 946 done: 947 return err; 948 } 949 950 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 951 unsigned short type, const void *daddr, 952 const void *saddr, unsigned int len) 953 { 954 struct ip6_tnl *t = netdev_priv(dev); 955 struct ipv6hdr *ipv6h; 956 __be16 *p; 957 958 ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h)); 959 ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb, 960 t->fl.u.ip6.flowlabel, 961 true, &t->fl.u.ip6)); 962 ipv6h->hop_limit = t->parms.hop_limit; 963 ipv6h->nexthdr = NEXTHDR_GRE; 964 ipv6h->saddr = t->parms.laddr; 965 ipv6h->daddr = t->parms.raddr; 966 967 p = (__be16 *)(ipv6h + 1); 968 p[0] = t->parms.o_flags; 969 p[1] = htons(type); 970 971 /* 972 * Set the source hardware address. 973 */ 974 975 if (saddr) 976 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 977 if (daddr) 978 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 979 if (!ipv6_addr_any(&ipv6h->daddr)) 980 return t->hlen; 981 982 return -t->hlen; 983 } 984 985 static const struct header_ops ip6gre_header_ops = { 986 .create = ip6gre_header, 987 }; 988 989 static const struct net_device_ops ip6gre_netdev_ops = { 990 .ndo_init = ip6gre_tunnel_init, 991 .ndo_uninit = ip6gre_tunnel_uninit, 992 .ndo_start_xmit = ip6gre_tunnel_xmit, 993 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 994 .ndo_change_mtu = ip6_tnl_change_mtu, 995 .ndo_get_stats64 = ip_tunnel_get_stats64, 996 .ndo_get_iflink = ip6_tnl_get_iflink, 997 }; 998 999 static void ip6gre_dev_free(struct net_device *dev) 1000 { 1001 struct ip6_tnl *t = netdev_priv(dev); 1002 1003 dst_cache_destroy(&t->dst_cache); 1004 free_percpu(dev->tstats); 1005 } 1006 1007 static void ip6gre_tunnel_setup(struct net_device *dev) 1008 { 1009 dev->netdev_ops = &ip6gre_netdev_ops; 1010 dev->needs_free_netdev = true; 1011 dev->priv_destructor = ip6gre_dev_free; 1012 1013 dev->type = ARPHRD_IP6GRE; 1014 1015 dev->flags |= IFF_NOARP; 1016 dev->addr_len = sizeof(struct in6_addr); 1017 netif_keep_dst(dev); 1018 /* This perm addr will be used as interface identifier by IPv6 */ 1019 dev->addr_assign_type = NET_ADDR_RANDOM; 1020 eth_random_addr(dev->perm_addr); 1021 } 1022 1023 static int ip6gre_tunnel_init_common(struct net_device *dev) 1024 { 1025 struct ip6_tnl *tunnel; 1026 int ret; 1027 int t_hlen; 1028 1029 tunnel = netdev_priv(dev); 1030 1031 tunnel->dev = dev; 1032 tunnel->net = dev_net(dev); 1033 strcpy(tunnel->parms.name, dev->name); 1034 1035 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1036 if (!dev->tstats) 1037 return -ENOMEM; 1038 1039 ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1040 if (ret) { 1041 free_percpu(dev->tstats); 1042 dev->tstats = NULL; 1043 return ret; 1044 } 1045 1046 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 1047 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 1048 t_hlen = tunnel->hlen + sizeof(struct ipv6hdr); 1049 1050 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1051 dev->mtu = ETH_DATA_LEN - t_hlen; 1052 if (dev->type == ARPHRD_ETHER) 1053 dev->mtu -= ETH_HLEN; 1054 if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1055 dev->mtu -= 8; 1056 1057 return 0; 1058 } 1059 1060 static int ip6gre_tunnel_init(struct net_device *dev) 1061 { 1062 struct ip6_tnl *tunnel; 1063 int ret; 1064 1065 ret = ip6gre_tunnel_init_common(dev); 1066 if (ret) 1067 return ret; 1068 1069 tunnel = netdev_priv(dev); 1070 1071 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1072 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1073 1074 if (ipv6_addr_any(&tunnel->parms.raddr)) 1075 dev->header_ops = &ip6gre_header_ops; 1076 1077 return 0; 1078 } 1079 1080 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1081 { 1082 struct ip6_tnl *tunnel = netdev_priv(dev); 1083 1084 tunnel->dev = dev; 1085 tunnel->net = dev_net(dev); 1086 strcpy(tunnel->parms.name, dev->name); 1087 1088 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1089 1090 dev_hold(dev); 1091 } 1092 1093 1094 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1095 .handler = gre_rcv, 1096 .err_handler = ip6gre_err, 1097 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1098 }; 1099 1100 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 1101 { 1102 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1103 struct net_device *dev, *aux; 1104 int prio; 1105 1106 for_each_netdev_safe(net, dev, aux) 1107 if (dev->rtnl_link_ops == &ip6gre_link_ops || 1108 dev->rtnl_link_ops == &ip6gre_tap_ops) 1109 unregister_netdevice_queue(dev, head); 1110 1111 for (prio = 0; prio < 4; prio++) { 1112 int h; 1113 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) { 1114 struct ip6_tnl *t; 1115 1116 t = rtnl_dereference(ign->tunnels[prio][h]); 1117 1118 while (t) { 1119 /* If dev is in the same netns, it has already 1120 * been added to the list by the previous loop. 1121 */ 1122 if (!net_eq(dev_net(t->dev), net)) 1123 unregister_netdevice_queue(t->dev, 1124 head); 1125 t = rtnl_dereference(t->next); 1126 } 1127 } 1128 } 1129 } 1130 1131 static int __net_init ip6gre_init_net(struct net *net) 1132 { 1133 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1134 int err; 1135 1136 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1137 NET_NAME_UNKNOWN, 1138 ip6gre_tunnel_setup); 1139 if (!ign->fb_tunnel_dev) { 1140 err = -ENOMEM; 1141 goto err_alloc_dev; 1142 } 1143 dev_net_set(ign->fb_tunnel_dev, net); 1144 /* FB netdevice is special: we have one, and only one per netns. 1145 * Allowing to move it to another netns is clearly unsafe. 1146 */ 1147 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1148 1149 1150 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1151 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1152 1153 err = register_netdev(ign->fb_tunnel_dev); 1154 if (err) 1155 goto err_reg_dev; 1156 1157 rcu_assign_pointer(ign->tunnels_wc[0], 1158 netdev_priv(ign->fb_tunnel_dev)); 1159 return 0; 1160 1161 err_reg_dev: 1162 free_netdev(ign->fb_tunnel_dev); 1163 err_alloc_dev: 1164 return err; 1165 } 1166 1167 static void __net_exit ip6gre_exit_net(struct net *net) 1168 { 1169 LIST_HEAD(list); 1170 1171 rtnl_lock(); 1172 ip6gre_destroy_tunnels(net, &list); 1173 unregister_netdevice_many(&list); 1174 rtnl_unlock(); 1175 } 1176 1177 static struct pernet_operations ip6gre_net_ops = { 1178 .init = ip6gre_init_net, 1179 .exit = ip6gre_exit_net, 1180 .id = &ip6gre_net_id, 1181 .size = sizeof(struct ip6gre_net), 1182 }; 1183 1184 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1185 struct netlink_ext_ack *extack) 1186 { 1187 __be16 flags; 1188 1189 if (!data) 1190 return 0; 1191 1192 flags = 0; 1193 if (data[IFLA_GRE_IFLAGS]) 1194 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1195 if (data[IFLA_GRE_OFLAGS]) 1196 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1197 if (flags & (GRE_VERSION|GRE_ROUTING)) 1198 return -EINVAL; 1199 1200 return 0; 1201 } 1202 1203 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1204 struct netlink_ext_ack *extack) 1205 { 1206 struct in6_addr daddr; 1207 1208 if (tb[IFLA_ADDRESS]) { 1209 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1210 return -EINVAL; 1211 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1212 return -EADDRNOTAVAIL; 1213 } 1214 1215 if (!data) 1216 goto out; 1217 1218 if (data[IFLA_GRE_REMOTE]) { 1219 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1220 if (ipv6_addr_any(&daddr)) 1221 return -EINVAL; 1222 } 1223 1224 out: 1225 return ip6gre_tunnel_validate(tb, data, extack); 1226 } 1227 1228 1229 static void ip6gre_netlink_parms(struct nlattr *data[], 1230 struct __ip6_tnl_parm *parms) 1231 { 1232 memset(parms, 0, sizeof(*parms)); 1233 1234 if (!data) 1235 return; 1236 1237 if (data[IFLA_GRE_LINK]) 1238 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1239 1240 if (data[IFLA_GRE_IFLAGS]) 1241 parms->i_flags = gre_flags_to_tnl_flags( 1242 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1243 1244 if (data[IFLA_GRE_OFLAGS]) 1245 parms->o_flags = gre_flags_to_tnl_flags( 1246 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1247 1248 if (data[IFLA_GRE_IKEY]) 1249 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1250 1251 if (data[IFLA_GRE_OKEY]) 1252 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1253 1254 if (data[IFLA_GRE_LOCAL]) 1255 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]); 1256 1257 if (data[IFLA_GRE_REMOTE]) 1258 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1259 1260 if (data[IFLA_GRE_TTL]) 1261 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1262 1263 if (data[IFLA_GRE_ENCAP_LIMIT]) 1264 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1265 1266 if (data[IFLA_GRE_FLOWINFO]) 1267 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]); 1268 1269 if (data[IFLA_GRE_FLAGS]) 1270 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1271 1272 if (data[IFLA_GRE_FWMARK]) 1273 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1274 } 1275 1276 static int ip6gre_tap_init(struct net_device *dev) 1277 { 1278 struct ip6_tnl *tunnel; 1279 int ret; 1280 1281 ret = ip6gre_tunnel_init_common(dev); 1282 if (ret) 1283 return ret; 1284 1285 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1286 1287 tunnel = netdev_priv(dev); 1288 1289 ip6gre_tnl_link_config(tunnel, 1); 1290 1291 return 0; 1292 } 1293 1294 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1295 .ndo_init = ip6gre_tap_init, 1296 .ndo_uninit = ip6gre_tunnel_uninit, 1297 .ndo_start_xmit = ip6gre_tunnel_xmit, 1298 .ndo_set_mac_address = eth_mac_addr, 1299 .ndo_validate_addr = eth_validate_addr, 1300 .ndo_change_mtu = ip6_tnl_change_mtu, 1301 .ndo_get_stats64 = ip_tunnel_get_stats64, 1302 .ndo_get_iflink = ip6_tnl_get_iflink, 1303 }; 1304 1305 #define GRE6_FEATURES (NETIF_F_SG | \ 1306 NETIF_F_FRAGLIST | \ 1307 NETIF_F_HIGHDMA | \ 1308 NETIF_F_HW_CSUM) 1309 1310 static void ip6gre_tap_setup(struct net_device *dev) 1311 { 1312 1313 ether_setup(dev); 1314 1315 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1316 dev->needs_free_netdev = true; 1317 dev->priv_destructor = ip6gre_dev_free; 1318 1319 dev->features |= NETIF_F_NETNS_LOCAL; 1320 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1321 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1322 netif_keep_dst(dev); 1323 } 1324 1325 static bool ip6gre_netlink_encap_parms(struct nlattr *data[], 1326 struct ip_tunnel_encap *ipencap) 1327 { 1328 bool ret = false; 1329 1330 memset(ipencap, 0, sizeof(*ipencap)); 1331 1332 if (!data) 1333 return ret; 1334 1335 if (data[IFLA_GRE_ENCAP_TYPE]) { 1336 ret = true; 1337 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1338 } 1339 1340 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1341 ret = true; 1342 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1343 } 1344 1345 if (data[IFLA_GRE_ENCAP_SPORT]) { 1346 ret = true; 1347 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1348 } 1349 1350 if (data[IFLA_GRE_ENCAP_DPORT]) { 1351 ret = true; 1352 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1353 } 1354 1355 return ret; 1356 } 1357 1358 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1359 struct nlattr *tb[], struct nlattr *data[], 1360 struct netlink_ext_ack *extack) 1361 { 1362 struct ip6_tnl *nt; 1363 struct net *net = dev_net(dev); 1364 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1365 struct ip_tunnel_encap ipencap; 1366 int err; 1367 1368 nt = netdev_priv(dev); 1369 1370 if (ip6gre_netlink_encap_parms(data, &ipencap)) { 1371 int err = ip6_tnl_encap_setup(nt, &ipencap); 1372 1373 if (err < 0) 1374 return err; 1375 } 1376 1377 ip6gre_netlink_parms(data, &nt->parms); 1378 1379 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1380 return -EEXIST; 1381 1382 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1383 eth_hw_addr_random(dev); 1384 1385 nt->dev = dev; 1386 nt->net = dev_net(dev); 1387 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1388 1389 dev->features |= GRE6_FEATURES; 1390 dev->hw_features |= GRE6_FEATURES; 1391 1392 if (!(nt->parms.o_flags & TUNNEL_SEQ)) { 1393 /* TCP offload with GRE SEQ is not supported, nor 1394 * can we support 2 levels of outer headers requiring 1395 * an update. 1396 */ 1397 if (!(nt->parms.o_flags & TUNNEL_CSUM) || 1398 (nt->encap.type == TUNNEL_ENCAP_NONE)) { 1399 dev->features |= NETIF_F_GSO_SOFTWARE; 1400 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 1401 } 1402 1403 /* Can use a lockless transmit, unless we generate 1404 * output sequences 1405 */ 1406 dev->features |= NETIF_F_LLTX; 1407 } 1408 1409 err = register_netdevice(dev); 1410 if (err) 1411 goto out; 1412 1413 dev_hold(dev); 1414 ip6gre_tunnel_link(ign, nt); 1415 1416 out: 1417 return err; 1418 } 1419 1420 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1421 struct nlattr *data[], 1422 struct netlink_ext_ack *extack) 1423 { 1424 struct ip6_tnl *t, *nt = netdev_priv(dev); 1425 struct net *net = nt->net; 1426 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1427 struct __ip6_tnl_parm p; 1428 struct ip_tunnel_encap ipencap; 1429 1430 if (dev == ign->fb_tunnel_dev) 1431 return -EINVAL; 1432 1433 if (ip6gre_netlink_encap_parms(data, &ipencap)) { 1434 int err = ip6_tnl_encap_setup(nt, &ipencap); 1435 1436 if (err < 0) 1437 return err; 1438 } 1439 1440 ip6gre_netlink_parms(data, &p); 1441 1442 t = ip6gre_tunnel_locate(net, &p, 0); 1443 1444 if (t) { 1445 if (t->dev != dev) 1446 return -EEXIST; 1447 } else { 1448 t = nt; 1449 } 1450 1451 ip6gre_tunnel_unlink(ign, t); 1452 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1453 ip6gre_tunnel_link(ign, t); 1454 return 0; 1455 } 1456 1457 static void ip6gre_dellink(struct net_device *dev, struct list_head *head) 1458 { 1459 struct net *net = dev_net(dev); 1460 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1461 1462 if (dev != ign->fb_tunnel_dev) 1463 unregister_netdevice_queue(dev, head); 1464 } 1465 1466 static size_t ip6gre_get_size(const struct net_device *dev) 1467 { 1468 return 1469 /* IFLA_GRE_LINK */ 1470 nla_total_size(4) + 1471 /* IFLA_GRE_IFLAGS */ 1472 nla_total_size(2) + 1473 /* IFLA_GRE_OFLAGS */ 1474 nla_total_size(2) + 1475 /* IFLA_GRE_IKEY */ 1476 nla_total_size(4) + 1477 /* IFLA_GRE_OKEY */ 1478 nla_total_size(4) + 1479 /* IFLA_GRE_LOCAL */ 1480 nla_total_size(sizeof(struct in6_addr)) + 1481 /* IFLA_GRE_REMOTE */ 1482 nla_total_size(sizeof(struct in6_addr)) + 1483 /* IFLA_GRE_TTL */ 1484 nla_total_size(1) + 1485 /* IFLA_GRE_ENCAP_LIMIT */ 1486 nla_total_size(1) + 1487 /* IFLA_GRE_FLOWINFO */ 1488 nla_total_size(4) + 1489 /* IFLA_GRE_FLAGS */ 1490 nla_total_size(4) + 1491 /* IFLA_GRE_ENCAP_TYPE */ 1492 nla_total_size(2) + 1493 /* IFLA_GRE_ENCAP_FLAGS */ 1494 nla_total_size(2) + 1495 /* IFLA_GRE_ENCAP_SPORT */ 1496 nla_total_size(2) + 1497 /* IFLA_GRE_ENCAP_DPORT */ 1498 nla_total_size(2) + 1499 /* IFLA_GRE_FWMARK */ 1500 nla_total_size(4) + 1501 0; 1502 } 1503 1504 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1505 { 1506 struct ip6_tnl *t = netdev_priv(dev); 1507 struct __ip6_tnl_parm *p = &t->parms; 1508 1509 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1510 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1511 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1512 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1513 gre_tnl_flags_to_gre_flags(p->o_flags)) || 1514 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1515 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1516 nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) || 1517 nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) || 1518 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1519 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1520 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1521 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) || 1522 nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark)) 1523 goto nla_put_failure; 1524 1525 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1526 t->encap.type) || 1527 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1528 t->encap.sport) || 1529 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1530 t->encap.dport) || 1531 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1532 t->encap.flags)) 1533 goto nla_put_failure; 1534 1535 return 0; 1536 1537 nla_put_failure: 1538 return -EMSGSIZE; 1539 } 1540 1541 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1542 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1543 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1544 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1545 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1546 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1547 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1548 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1549 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1550 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1551 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1552 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1553 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1554 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1555 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1556 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1557 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1558 }; 1559 1560 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1561 .kind = "ip6gre", 1562 .maxtype = IFLA_GRE_MAX, 1563 .policy = ip6gre_policy, 1564 .priv_size = sizeof(struct ip6_tnl), 1565 .setup = ip6gre_tunnel_setup, 1566 .validate = ip6gre_tunnel_validate, 1567 .newlink = ip6gre_newlink, 1568 .changelink = ip6gre_changelink, 1569 .dellink = ip6gre_dellink, 1570 .get_size = ip6gre_get_size, 1571 .fill_info = ip6gre_fill_info, 1572 .get_link_net = ip6_tnl_get_link_net, 1573 }; 1574 1575 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1576 .kind = "ip6gretap", 1577 .maxtype = IFLA_GRE_MAX, 1578 .policy = ip6gre_policy, 1579 .priv_size = sizeof(struct ip6_tnl), 1580 .setup = ip6gre_tap_setup, 1581 .validate = ip6gre_tap_validate, 1582 .newlink = ip6gre_newlink, 1583 .changelink = ip6gre_changelink, 1584 .get_size = ip6gre_get_size, 1585 .fill_info = ip6gre_fill_info, 1586 .get_link_net = ip6_tnl_get_link_net, 1587 }; 1588 1589 /* 1590 * And now the modules code and kernel interface. 1591 */ 1592 1593 static int __init ip6gre_init(void) 1594 { 1595 int err; 1596 1597 pr_info("GRE over IPv6 tunneling driver\n"); 1598 1599 err = register_pernet_device(&ip6gre_net_ops); 1600 if (err < 0) 1601 return err; 1602 1603 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1604 if (err < 0) { 1605 pr_info("%s: can't add protocol\n", __func__); 1606 goto add_proto_failed; 1607 } 1608 1609 err = rtnl_link_register(&ip6gre_link_ops); 1610 if (err < 0) 1611 goto rtnl_link_failed; 1612 1613 err = rtnl_link_register(&ip6gre_tap_ops); 1614 if (err < 0) 1615 goto tap_ops_failed; 1616 1617 out: 1618 return err; 1619 1620 tap_ops_failed: 1621 rtnl_link_unregister(&ip6gre_link_ops); 1622 rtnl_link_failed: 1623 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1624 add_proto_failed: 1625 unregister_pernet_device(&ip6gre_net_ops); 1626 goto out; 1627 } 1628 1629 static void __exit ip6gre_fini(void) 1630 { 1631 rtnl_link_unregister(&ip6gre_tap_ops); 1632 rtnl_link_unregister(&ip6gre_link_ops); 1633 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1634 unregister_pernet_device(&ip6gre_net_ops); 1635 } 1636 1637 module_init(ip6gre_init); 1638 module_exit(ip6gre_fini); 1639 MODULE_LICENSE("GPL"); 1640 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1641 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1642 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1643 MODULE_ALIAS_RTNL_LINK("ip6gretap"); 1644 MODULE_ALIAS_NETDEV("ip6gre0"); 1645