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); 340 341 if (register_netdevice(dev) < 0) 342 goto failed_free; 343 344 ip6gre_tnl_link_config(nt, 1); 345 346 /* Can use a lockless transmit, unless we generate output sequences */ 347 if (!(nt->parms.o_flags & TUNNEL_SEQ)) 348 dev->features |= NETIF_F_LLTX; 349 350 dev_hold(dev); 351 ip6gre_tunnel_link(ign, nt); 352 return nt; 353 354 failed_free: 355 free_netdev(dev); 356 return NULL; 357 } 358 359 static void ip6gre_tunnel_uninit(struct net_device *dev) 360 { 361 struct ip6_tnl *t = netdev_priv(dev); 362 struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id); 363 364 ip6gre_tunnel_unlink(ign, t); 365 dst_cache_reset(&t->dst_cache); 366 dev_put(dev); 367 } 368 369 370 static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 371 u8 type, u8 code, int offset, __be32 info) 372 { 373 struct net *net = dev_net(skb->dev); 374 const struct gre_base_hdr *greh; 375 const struct ipv6hdr *ipv6h; 376 int grehlen = sizeof(*greh); 377 struct ip6_tnl *t; 378 int key_off = 0; 379 __be16 flags; 380 __be32 key; 381 382 if (!pskb_may_pull(skb, offset + grehlen)) 383 return; 384 greh = (const struct gre_base_hdr *)(skb->data + offset); 385 flags = greh->flags; 386 if (flags & (GRE_VERSION | GRE_ROUTING)) 387 return; 388 if (flags & GRE_CSUM) 389 grehlen += 4; 390 if (flags & GRE_KEY) { 391 key_off = grehlen + offset; 392 grehlen += 4; 393 } 394 395 if (!pskb_may_pull(skb, offset + grehlen)) 396 return; 397 ipv6h = (const struct ipv6hdr *)skb->data; 398 greh = (const struct gre_base_hdr *)(skb->data + offset); 399 key = key_off ? *(__be32 *)(skb->data + key_off) : 0; 400 401 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 402 key, greh->protocol); 403 if (!t) 404 return; 405 406 switch (type) { 407 struct ipv6_tlv_tnl_enc_lim *tel; 408 __u32 teli; 409 case ICMPV6_DEST_UNREACH: 410 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n", 411 t->parms.name); 412 if (code != ICMPV6_PORT_UNREACH) 413 break; 414 return; 415 case ICMPV6_TIME_EXCEED: 416 if (code == ICMPV6_EXC_HOPLIMIT) { 417 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", 418 t->parms.name); 419 break; 420 } 421 return; 422 case ICMPV6_PARAMPROB: 423 teli = 0; 424 if (code == ICMPV6_HDR_FIELD) 425 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); 426 427 if (teli && teli == be32_to_cpu(info) - 2) { 428 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; 429 if (tel->encap_limit == 0) { 430 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", 431 t->parms.name); 432 } 433 } else { 434 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n", 435 t->parms.name); 436 } 437 return; 438 case ICMPV6_PKT_TOOBIG: 439 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 440 return; 441 case NDISC_REDIRECT: 442 ip6_redirect(skb, net, skb->dev->ifindex, 0, 443 sock_net_uid(net, NULL)); 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, log_ecn_error); 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 __be16 protocol; 507 508 if (dev->type == ARPHRD_ETHER) 509 IPCB(skb)->flags = 0; 510 511 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) 512 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr; 513 else 514 fl6->daddr = tunnel->parms.raddr; 515 516 if (tunnel->parms.o_flags & TUNNEL_SEQ) 517 tunnel->o_seqno++; 518 519 /* Push GRE header. */ 520 protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto; 521 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags, 522 protocol, tunnel->parms.o_key, htonl(tunnel->o_seqno)); 523 524 return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu, 525 NEXTHDR_GRE); 526 } 527 528 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 529 { 530 struct ip6_tnl *t = netdev_priv(dev); 531 const struct iphdr *iph = ip_hdr(skb); 532 int encap_limit = -1; 533 struct flowi6 fl6; 534 __u8 dsfield; 535 __u32 mtu; 536 int err; 537 538 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 539 540 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 541 encap_limit = t->parms.encap_limit; 542 543 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 544 545 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 546 dsfield = ipv4_get_dsfield(iph); 547 else 548 dsfield = ip6_tclass(t->parms.flowinfo); 549 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 550 fl6.flowi6_mark = skb->mark; 551 else 552 fl6.flowi6_mark = t->parms.fwmark; 553 554 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 555 556 err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); 557 if (err) 558 return -1; 559 560 err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 561 skb->protocol); 562 if (err != 0) { 563 /* XXX: send ICMP error even if DF is not set. */ 564 if (err == -EMSGSIZE) 565 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 566 htonl(mtu)); 567 return -1; 568 } 569 570 return 0; 571 } 572 573 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 574 { 575 struct ip6_tnl *t = netdev_priv(dev); 576 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 577 int encap_limit = -1; 578 __u16 offset; 579 struct flowi6 fl6; 580 __u8 dsfield; 581 __u32 mtu; 582 int err; 583 584 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 585 return -1; 586 587 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 588 /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */ 589 ipv6h = ipv6_hdr(skb); 590 591 if (offset > 0) { 592 struct ipv6_tlv_tnl_enc_lim *tel; 593 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 594 if (tel->encap_limit == 0) { 595 icmpv6_send(skb, ICMPV6_PARAMPROB, 596 ICMPV6_HDR_FIELD, offset + 2); 597 return -1; 598 } 599 encap_limit = tel->encap_limit - 1; 600 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 601 encap_limit = t->parms.encap_limit; 602 603 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 604 605 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 606 dsfield = ipv6_get_dsfield(ipv6h); 607 else 608 dsfield = ip6_tclass(t->parms.flowinfo); 609 610 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 611 fl6.flowlabel |= ip6_flowlabel(ipv6h); 612 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 613 fl6.flowi6_mark = skb->mark; 614 else 615 fl6.flowi6_mark = t->parms.fwmark; 616 617 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 618 619 if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM))) 620 return -1; 621 622 err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, 623 &mtu, skb->protocol); 624 if (err != 0) { 625 if (err == -EMSGSIZE) 626 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 627 return -1; 628 } 629 630 return 0; 631 } 632 633 /** 634 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 635 * @t: the outgoing tunnel device 636 * @hdr: IPv6 header from the incoming packet 637 * 638 * Description: 639 * Avoid trivial tunneling loop by checking that tunnel exit-point 640 * doesn't match source of incoming packet. 641 * 642 * Return: 643 * 1 if conflict, 644 * 0 else 645 **/ 646 647 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 648 const struct ipv6hdr *hdr) 649 { 650 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 651 } 652 653 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 654 { 655 struct ip6_tnl *t = netdev_priv(dev); 656 int encap_limit = -1; 657 struct flowi6 fl6; 658 __u32 mtu; 659 int err; 660 661 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 662 encap_limit = t->parms.encap_limit; 663 664 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 665 666 err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); 667 if (err) 668 return err; 669 670 err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol); 671 672 return err; 673 } 674 675 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 676 struct net_device *dev) 677 { 678 struct ip6_tnl *t = netdev_priv(dev); 679 struct net_device_stats *stats = &t->dev->stats; 680 int ret; 681 682 if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr)) 683 goto tx_err; 684 685 switch (skb->protocol) { 686 case htons(ETH_P_IP): 687 ret = ip6gre_xmit_ipv4(skb, dev); 688 break; 689 case htons(ETH_P_IPV6): 690 ret = ip6gre_xmit_ipv6(skb, dev); 691 break; 692 default: 693 ret = ip6gre_xmit_other(skb, dev); 694 break; 695 } 696 697 if (ret < 0) 698 goto tx_err; 699 700 return NETDEV_TX_OK; 701 702 tx_err: 703 stats->tx_errors++; 704 stats->tx_dropped++; 705 kfree_skb(skb); 706 return NETDEV_TX_OK; 707 } 708 709 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 710 { 711 struct net_device *dev = t->dev; 712 struct __ip6_tnl_parm *p = &t->parms; 713 struct flowi6 *fl6 = &t->fl.u.ip6; 714 int t_hlen; 715 716 if (dev->type != ARPHRD_ETHER) { 717 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 718 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 719 } 720 721 /* Set up flowi template */ 722 fl6->saddr = p->laddr; 723 fl6->daddr = p->raddr; 724 fl6->flowi6_oif = p->link; 725 fl6->flowlabel = 0; 726 fl6->flowi6_proto = IPPROTO_GRE; 727 728 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 729 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 730 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 731 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 732 733 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 734 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 735 736 if (p->flags&IP6_TNL_F_CAP_XMIT && 737 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 738 dev->flags |= IFF_POINTOPOINT; 739 else 740 dev->flags &= ~IFF_POINTOPOINT; 741 742 t->tun_hlen = gre_calc_hlen(t->parms.o_flags); 743 744 t->hlen = t->encap_hlen + t->tun_hlen; 745 746 t_hlen = t->hlen + sizeof(struct ipv6hdr); 747 748 if (p->flags & IP6_TNL_F_CAP_XMIT) { 749 int strict = (ipv6_addr_type(&p->raddr) & 750 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 751 752 struct rt6_info *rt = rt6_lookup(t->net, 753 &p->raddr, &p->laddr, 754 p->link, strict); 755 756 if (!rt) 757 return; 758 759 if (rt->dst.dev) { 760 dev->hard_header_len = rt->dst.dev->hard_header_len + 761 t_hlen; 762 763 if (set_mtu) { 764 dev->mtu = rt->dst.dev->mtu - t_hlen; 765 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 766 dev->mtu -= 8; 767 if (dev->type == ARPHRD_ETHER) 768 dev->mtu -= ETH_HLEN; 769 770 if (dev->mtu < IPV6_MIN_MTU) 771 dev->mtu = IPV6_MIN_MTU; 772 } 773 } 774 ip6_rt_put(rt); 775 } 776 } 777 778 static int ip6gre_tnl_change(struct ip6_tnl *t, 779 const struct __ip6_tnl_parm *p, int set_mtu) 780 { 781 t->parms.laddr = p->laddr; 782 t->parms.raddr = p->raddr; 783 t->parms.flags = p->flags; 784 t->parms.hop_limit = p->hop_limit; 785 t->parms.encap_limit = p->encap_limit; 786 t->parms.flowinfo = p->flowinfo; 787 t->parms.link = p->link; 788 t->parms.proto = p->proto; 789 t->parms.i_key = p->i_key; 790 t->parms.o_key = p->o_key; 791 t->parms.i_flags = p->i_flags; 792 t->parms.o_flags = p->o_flags; 793 t->parms.fwmark = p->fwmark; 794 dst_cache_reset(&t->dst_cache); 795 ip6gre_tnl_link_config(t, set_mtu); 796 return 0; 797 } 798 799 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 800 const struct ip6_tnl_parm2 *u) 801 { 802 p->laddr = u->laddr; 803 p->raddr = u->raddr; 804 p->flags = u->flags; 805 p->hop_limit = u->hop_limit; 806 p->encap_limit = u->encap_limit; 807 p->flowinfo = u->flowinfo; 808 p->link = u->link; 809 p->i_key = u->i_key; 810 p->o_key = u->o_key; 811 p->i_flags = gre_flags_to_tnl_flags(u->i_flags); 812 p->o_flags = gre_flags_to_tnl_flags(u->o_flags); 813 memcpy(p->name, u->name, sizeof(u->name)); 814 } 815 816 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 817 const struct __ip6_tnl_parm *p) 818 { 819 u->proto = IPPROTO_GRE; 820 u->laddr = p->laddr; 821 u->raddr = p->raddr; 822 u->flags = p->flags; 823 u->hop_limit = p->hop_limit; 824 u->encap_limit = p->encap_limit; 825 u->flowinfo = p->flowinfo; 826 u->link = p->link; 827 u->i_key = p->i_key; 828 u->o_key = p->o_key; 829 u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags); 830 u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags); 831 memcpy(u->name, p->name, sizeof(u->name)); 832 } 833 834 static int ip6gre_tunnel_ioctl(struct net_device *dev, 835 struct ifreq *ifr, int cmd) 836 { 837 int err = 0; 838 struct ip6_tnl_parm2 p; 839 struct __ip6_tnl_parm p1; 840 struct ip6_tnl *t = netdev_priv(dev); 841 struct net *net = t->net; 842 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 843 844 memset(&p1, 0, sizeof(p1)); 845 846 switch (cmd) { 847 case SIOCGETTUNNEL: 848 if (dev == ign->fb_tunnel_dev) { 849 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 850 err = -EFAULT; 851 break; 852 } 853 ip6gre_tnl_parm_from_user(&p1, &p); 854 t = ip6gre_tunnel_locate(net, &p1, 0); 855 if (!t) 856 t = netdev_priv(dev); 857 } 858 memset(&p, 0, sizeof(p)); 859 ip6gre_tnl_parm_to_user(&p, &t->parms); 860 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 861 err = -EFAULT; 862 break; 863 864 case SIOCADDTUNNEL: 865 case SIOCCHGTUNNEL: 866 err = -EPERM; 867 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 868 goto done; 869 870 err = -EFAULT; 871 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 872 goto done; 873 874 err = -EINVAL; 875 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 876 goto done; 877 878 if (!(p.i_flags&GRE_KEY)) 879 p.i_key = 0; 880 if (!(p.o_flags&GRE_KEY)) 881 p.o_key = 0; 882 883 ip6gre_tnl_parm_from_user(&p1, &p); 884 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 885 886 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 887 if (t) { 888 if (t->dev != dev) { 889 err = -EEXIST; 890 break; 891 } 892 } else { 893 t = netdev_priv(dev); 894 895 ip6gre_tunnel_unlink(ign, t); 896 synchronize_net(); 897 ip6gre_tnl_change(t, &p1, 1); 898 ip6gre_tunnel_link(ign, t); 899 netdev_state_change(dev); 900 } 901 } 902 903 if (t) { 904 err = 0; 905 906 memset(&p, 0, sizeof(p)); 907 ip6gre_tnl_parm_to_user(&p, &t->parms); 908 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 909 err = -EFAULT; 910 } else 911 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 912 break; 913 914 case SIOCDELTUNNEL: 915 err = -EPERM; 916 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 917 goto done; 918 919 if (dev == ign->fb_tunnel_dev) { 920 err = -EFAULT; 921 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 922 goto done; 923 err = -ENOENT; 924 ip6gre_tnl_parm_from_user(&p1, &p); 925 t = ip6gre_tunnel_locate(net, &p1, 0); 926 if (!t) 927 goto done; 928 err = -EPERM; 929 if (t == netdev_priv(ign->fb_tunnel_dev)) 930 goto done; 931 dev = t->dev; 932 } 933 unregister_netdevice(dev); 934 err = 0; 935 break; 936 937 default: 938 err = -EINVAL; 939 } 940 941 done: 942 return err; 943 } 944 945 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 946 unsigned short type, const void *daddr, 947 const void *saddr, unsigned int len) 948 { 949 struct ip6_tnl *t = netdev_priv(dev); 950 struct ipv6hdr *ipv6h; 951 __be16 *p; 952 953 ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h)); 954 ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb, 955 t->fl.u.ip6.flowlabel, 956 true, &t->fl.u.ip6)); 957 ipv6h->hop_limit = t->parms.hop_limit; 958 ipv6h->nexthdr = NEXTHDR_GRE; 959 ipv6h->saddr = t->parms.laddr; 960 ipv6h->daddr = t->parms.raddr; 961 962 p = (__be16 *)(ipv6h + 1); 963 p[0] = t->parms.o_flags; 964 p[1] = htons(type); 965 966 /* 967 * Set the source hardware address. 968 */ 969 970 if (saddr) 971 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 972 if (daddr) 973 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 974 if (!ipv6_addr_any(&ipv6h->daddr)) 975 return t->hlen; 976 977 return -t->hlen; 978 } 979 980 static const struct header_ops ip6gre_header_ops = { 981 .create = ip6gre_header, 982 }; 983 984 static const struct net_device_ops ip6gre_netdev_ops = { 985 .ndo_init = ip6gre_tunnel_init, 986 .ndo_uninit = ip6gre_tunnel_uninit, 987 .ndo_start_xmit = ip6gre_tunnel_xmit, 988 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 989 .ndo_change_mtu = ip6_tnl_change_mtu, 990 .ndo_get_stats64 = ip_tunnel_get_stats64, 991 .ndo_get_iflink = ip6_tnl_get_iflink, 992 }; 993 994 static void ip6gre_dev_free(struct net_device *dev) 995 { 996 struct ip6_tnl *t = netdev_priv(dev); 997 998 dst_cache_destroy(&t->dst_cache); 999 free_percpu(dev->tstats); 1000 } 1001 1002 static void ip6gre_tunnel_setup(struct net_device *dev) 1003 { 1004 dev->netdev_ops = &ip6gre_netdev_ops; 1005 dev->needs_free_netdev = true; 1006 dev->priv_destructor = ip6gre_dev_free; 1007 1008 dev->type = ARPHRD_IP6GRE; 1009 1010 dev->flags |= IFF_NOARP; 1011 dev->addr_len = sizeof(struct in6_addr); 1012 netif_keep_dst(dev); 1013 /* This perm addr will be used as interface identifier by IPv6 */ 1014 dev->addr_assign_type = NET_ADDR_RANDOM; 1015 eth_random_addr(dev->perm_addr); 1016 } 1017 1018 #define GRE6_FEATURES (NETIF_F_SG | \ 1019 NETIF_F_FRAGLIST | \ 1020 NETIF_F_HIGHDMA | \ 1021 NETIF_F_HW_CSUM) 1022 1023 static void ip6gre_tnl_init_features(struct net_device *dev) 1024 { 1025 struct ip6_tnl *nt = netdev_priv(dev); 1026 1027 dev->features |= GRE6_FEATURES; 1028 dev->hw_features |= GRE6_FEATURES; 1029 1030 if (!(nt->parms.o_flags & TUNNEL_SEQ)) { 1031 /* TCP offload with GRE SEQ is not supported, nor 1032 * can we support 2 levels of outer headers requiring 1033 * an update. 1034 */ 1035 if (!(nt->parms.o_flags & TUNNEL_CSUM) || 1036 nt->encap.type == TUNNEL_ENCAP_NONE) { 1037 dev->features |= NETIF_F_GSO_SOFTWARE; 1038 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 1039 } 1040 1041 /* Can use a lockless transmit, unless we generate 1042 * output sequences 1043 */ 1044 dev->features |= NETIF_F_LLTX; 1045 } 1046 } 1047 1048 static int ip6gre_tunnel_init_common(struct net_device *dev) 1049 { 1050 struct ip6_tnl *tunnel; 1051 int ret; 1052 int t_hlen; 1053 1054 tunnel = netdev_priv(dev); 1055 1056 tunnel->dev = dev; 1057 tunnel->net = dev_net(dev); 1058 strcpy(tunnel->parms.name, dev->name); 1059 1060 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1061 if (!dev->tstats) 1062 return -ENOMEM; 1063 1064 ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1065 if (ret) { 1066 free_percpu(dev->tstats); 1067 dev->tstats = NULL; 1068 return ret; 1069 } 1070 1071 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 1072 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 1073 t_hlen = tunnel->hlen + sizeof(struct ipv6hdr); 1074 1075 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1076 dev->mtu = ETH_DATA_LEN - t_hlen; 1077 if (dev->type == ARPHRD_ETHER) 1078 dev->mtu -= ETH_HLEN; 1079 if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1080 dev->mtu -= 8; 1081 1082 ip6gre_tnl_init_features(dev); 1083 1084 return 0; 1085 } 1086 1087 static int ip6gre_tunnel_init(struct net_device *dev) 1088 { 1089 struct ip6_tnl *tunnel; 1090 int ret; 1091 1092 ret = ip6gre_tunnel_init_common(dev); 1093 if (ret) 1094 return ret; 1095 1096 tunnel = netdev_priv(dev); 1097 1098 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1099 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1100 1101 if (ipv6_addr_any(&tunnel->parms.raddr)) 1102 dev->header_ops = &ip6gre_header_ops; 1103 1104 return 0; 1105 } 1106 1107 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1108 { 1109 struct ip6_tnl *tunnel = netdev_priv(dev); 1110 1111 tunnel->dev = dev; 1112 tunnel->net = dev_net(dev); 1113 strcpy(tunnel->parms.name, dev->name); 1114 1115 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1116 1117 dev_hold(dev); 1118 } 1119 1120 1121 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1122 .handler = gre_rcv, 1123 .err_handler = ip6gre_err, 1124 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1125 }; 1126 1127 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 1128 { 1129 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1130 struct net_device *dev, *aux; 1131 int prio; 1132 1133 for_each_netdev_safe(net, dev, aux) 1134 if (dev->rtnl_link_ops == &ip6gre_link_ops || 1135 dev->rtnl_link_ops == &ip6gre_tap_ops) 1136 unregister_netdevice_queue(dev, head); 1137 1138 for (prio = 0; prio < 4; prio++) { 1139 int h; 1140 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) { 1141 struct ip6_tnl *t; 1142 1143 t = rtnl_dereference(ign->tunnels[prio][h]); 1144 1145 while (t) { 1146 /* If dev is in the same netns, it has already 1147 * been added to the list by the previous loop. 1148 */ 1149 if (!net_eq(dev_net(t->dev), net)) 1150 unregister_netdevice_queue(t->dev, 1151 head); 1152 t = rtnl_dereference(t->next); 1153 } 1154 } 1155 } 1156 } 1157 1158 static int __net_init ip6gre_init_net(struct net *net) 1159 { 1160 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1161 int err; 1162 1163 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1164 NET_NAME_UNKNOWN, 1165 ip6gre_tunnel_setup); 1166 if (!ign->fb_tunnel_dev) { 1167 err = -ENOMEM; 1168 goto err_alloc_dev; 1169 } 1170 dev_net_set(ign->fb_tunnel_dev, net); 1171 /* FB netdevice is special: we have one, and only one per netns. 1172 * Allowing to move it to another netns is clearly unsafe. 1173 */ 1174 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1175 1176 1177 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1178 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1179 1180 err = register_netdev(ign->fb_tunnel_dev); 1181 if (err) 1182 goto err_reg_dev; 1183 1184 rcu_assign_pointer(ign->tunnels_wc[0], 1185 netdev_priv(ign->fb_tunnel_dev)); 1186 return 0; 1187 1188 err_reg_dev: 1189 free_netdev(ign->fb_tunnel_dev); 1190 err_alloc_dev: 1191 return err; 1192 } 1193 1194 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list) 1195 { 1196 struct net *net; 1197 LIST_HEAD(list); 1198 1199 rtnl_lock(); 1200 list_for_each_entry(net, net_list, exit_list) 1201 ip6gre_destroy_tunnels(net, &list); 1202 unregister_netdevice_many(&list); 1203 rtnl_unlock(); 1204 } 1205 1206 static struct pernet_operations ip6gre_net_ops = { 1207 .init = ip6gre_init_net, 1208 .exit_batch = ip6gre_exit_batch_net, 1209 .id = &ip6gre_net_id, 1210 .size = sizeof(struct ip6gre_net), 1211 }; 1212 1213 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1214 struct netlink_ext_ack *extack) 1215 { 1216 __be16 flags; 1217 1218 if (!data) 1219 return 0; 1220 1221 flags = 0; 1222 if (data[IFLA_GRE_IFLAGS]) 1223 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1224 if (data[IFLA_GRE_OFLAGS]) 1225 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1226 if (flags & (GRE_VERSION|GRE_ROUTING)) 1227 return -EINVAL; 1228 1229 return 0; 1230 } 1231 1232 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1233 struct netlink_ext_ack *extack) 1234 { 1235 struct in6_addr daddr; 1236 1237 if (tb[IFLA_ADDRESS]) { 1238 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1239 return -EINVAL; 1240 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1241 return -EADDRNOTAVAIL; 1242 } 1243 1244 if (!data) 1245 goto out; 1246 1247 if (data[IFLA_GRE_REMOTE]) { 1248 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1249 if (ipv6_addr_any(&daddr)) 1250 return -EINVAL; 1251 } 1252 1253 out: 1254 return ip6gre_tunnel_validate(tb, data, extack); 1255 } 1256 1257 1258 static void ip6gre_netlink_parms(struct nlattr *data[], 1259 struct __ip6_tnl_parm *parms) 1260 { 1261 memset(parms, 0, sizeof(*parms)); 1262 1263 if (!data) 1264 return; 1265 1266 if (data[IFLA_GRE_LINK]) 1267 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1268 1269 if (data[IFLA_GRE_IFLAGS]) 1270 parms->i_flags = gre_flags_to_tnl_flags( 1271 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1272 1273 if (data[IFLA_GRE_OFLAGS]) 1274 parms->o_flags = gre_flags_to_tnl_flags( 1275 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1276 1277 if (data[IFLA_GRE_IKEY]) 1278 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1279 1280 if (data[IFLA_GRE_OKEY]) 1281 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1282 1283 if (data[IFLA_GRE_LOCAL]) 1284 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]); 1285 1286 if (data[IFLA_GRE_REMOTE]) 1287 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1288 1289 if (data[IFLA_GRE_TTL]) 1290 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1291 1292 if (data[IFLA_GRE_ENCAP_LIMIT]) 1293 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1294 1295 if (data[IFLA_GRE_FLOWINFO]) 1296 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]); 1297 1298 if (data[IFLA_GRE_FLAGS]) 1299 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1300 1301 if (data[IFLA_GRE_FWMARK]) 1302 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1303 } 1304 1305 static int ip6gre_tap_init(struct net_device *dev) 1306 { 1307 int ret; 1308 1309 ret = ip6gre_tunnel_init_common(dev); 1310 if (ret) 1311 return ret; 1312 1313 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1314 1315 return 0; 1316 } 1317 1318 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1319 .ndo_init = ip6gre_tap_init, 1320 .ndo_uninit = ip6gre_tunnel_uninit, 1321 .ndo_start_xmit = ip6gre_tunnel_xmit, 1322 .ndo_set_mac_address = eth_mac_addr, 1323 .ndo_validate_addr = eth_validate_addr, 1324 .ndo_change_mtu = ip6_tnl_change_mtu, 1325 .ndo_get_stats64 = ip_tunnel_get_stats64, 1326 .ndo_get_iflink = ip6_tnl_get_iflink, 1327 }; 1328 1329 static void ip6gre_tap_setup(struct net_device *dev) 1330 { 1331 1332 ether_setup(dev); 1333 1334 dev->max_mtu = 0; 1335 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1336 dev->needs_free_netdev = true; 1337 dev->priv_destructor = ip6gre_dev_free; 1338 1339 dev->features |= NETIF_F_NETNS_LOCAL; 1340 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1341 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1342 netif_keep_dst(dev); 1343 } 1344 1345 static bool ip6gre_netlink_encap_parms(struct nlattr *data[], 1346 struct ip_tunnel_encap *ipencap) 1347 { 1348 bool ret = false; 1349 1350 memset(ipencap, 0, sizeof(*ipencap)); 1351 1352 if (!data) 1353 return ret; 1354 1355 if (data[IFLA_GRE_ENCAP_TYPE]) { 1356 ret = true; 1357 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1358 } 1359 1360 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1361 ret = true; 1362 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1363 } 1364 1365 if (data[IFLA_GRE_ENCAP_SPORT]) { 1366 ret = true; 1367 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1368 } 1369 1370 if (data[IFLA_GRE_ENCAP_DPORT]) { 1371 ret = true; 1372 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1373 } 1374 1375 return ret; 1376 } 1377 1378 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1379 struct nlattr *tb[], struct nlattr *data[], 1380 struct netlink_ext_ack *extack) 1381 { 1382 struct ip6_tnl *nt; 1383 struct net *net = dev_net(dev); 1384 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1385 struct ip_tunnel_encap ipencap; 1386 int err; 1387 1388 nt = netdev_priv(dev); 1389 1390 if (ip6gre_netlink_encap_parms(data, &ipencap)) { 1391 int err = ip6_tnl_encap_setup(nt, &ipencap); 1392 1393 if (err < 0) 1394 return err; 1395 } 1396 1397 ip6gre_netlink_parms(data, &nt->parms); 1398 1399 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1400 return -EEXIST; 1401 1402 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1403 eth_hw_addr_random(dev); 1404 1405 nt->dev = dev; 1406 nt->net = dev_net(dev); 1407 1408 err = register_netdevice(dev); 1409 if (err) 1410 goto out; 1411 1412 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1413 1414 if (tb[IFLA_MTU]) 1415 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); 1416 1417 dev_hold(dev); 1418 ip6gre_tunnel_link(ign, nt); 1419 1420 out: 1421 return err; 1422 } 1423 1424 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1425 struct nlattr *data[], 1426 struct netlink_ext_ack *extack) 1427 { 1428 struct ip6_tnl *t, *nt = netdev_priv(dev); 1429 struct net *net = nt->net; 1430 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1431 struct __ip6_tnl_parm p; 1432 struct ip_tunnel_encap ipencap; 1433 1434 if (dev == ign->fb_tunnel_dev) 1435 return -EINVAL; 1436 1437 if (ip6gre_netlink_encap_parms(data, &ipencap)) { 1438 int err = ip6_tnl_encap_setup(nt, &ipencap); 1439 1440 if (err < 0) 1441 return err; 1442 } 1443 1444 ip6gre_netlink_parms(data, &p); 1445 1446 t = ip6gre_tunnel_locate(net, &p, 0); 1447 1448 if (t) { 1449 if (t->dev != dev) 1450 return -EEXIST; 1451 } else { 1452 t = nt; 1453 } 1454 1455 ip6gre_tunnel_unlink(ign, t); 1456 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1457 ip6gre_tunnel_link(ign, t); 1458 return 0; 1459 } 1460 1461 static void ip6gre_dellink(struct net_device *dev, struct list_head *head) 1462 { 1463 struct net *net = dev_net(dev); 1464 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1465 1466 if (dev != ign->fb_tunnel_dev) 1467 unregister_netdevice_queue(dev, head); 1468 } 1469 1470 static size_t ip6gre_get_size(const struct net_device *dev) 1471 { 1472 return 1473 /* IFLA_GRE_LINK */ 1474 nla_total_size(4) + 1475 /* IFLA_GRE_IFLAGS */ 1476 nla_total_size(2) + 1477 /* IFLA_GRE_OFLAGS */ 1478 nla_total_size(2) + 1479 /* IFLA_GRE_IKEY */ 1480 nla_total_size(4) + 1481 /* IFLA_GRE_OKEY */ 1482 nla_total_size(4) + 1483 /* IFLA_GRE_LOCAL */ 1484 nla_total_size(sizeof(struct in6_addr)) + 1485 /* IFLA_GRE_REMOTE */ 1486 nla_total_size(sizeof(struct in6_addr)) + 1487 /* IFLA_GRE_TTL */ 1488 nla_total_size(1) + 1489 /* IFLA_GRE_ENCAP_LIMIT */ 1490 nla_total_size(1) + 1491 /* IFLA_GRE_FLOWINFO */ 1492 nla_total_size(4) + 1493 /* IFLA_GRE_FLAGS */ 1494 nla_total_size(4) + 1495 /* IFLA_GRE_ENCAP_TYPE */ 1496 nla_total_size(2) + 1497 /* IFLA_GRE_ENCAP_FLAGS */ 1498 nla_total_size(2) + 1499 /* IFLA_GRE_ENCAP_SPORT */ 1500 nla_total_size(2) + 1501 /* IFLA_GRE_ENCAP_DPORT */ 1502 nla_total_size(2) + 1503 /* IFLA_GRE_FWMARK */ 1504 nla_total_size(4) + 1505 0; 1506 } 1507 1508 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1509 { 1510 struct ip6_tnl *t = netdev_priv(dev); 1511 struct __ip6_tnl_parm *p = &t->parms; 1512 1513 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1514 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1515 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1516 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1517 gre_tnl_flags_to_gre_flags(p->o_flags)) || 1518 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1519 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1520 nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) || 1521 nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) || 1522 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1523 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1524 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1525 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) || 1526 nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark)) 1527 goto nla_put_failure; 1528 1529 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1530 t->encap.type) || 1531 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1532 t->encap.sport) || 1533 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1534 t->encap.dport) || 1535 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1536 t->encap.flags)) 1537 goto nla_put_failure; 1538 1539 return 0; 1540 1541 nla_put_failure: 1542 return -EMSGSIZE; 1543 } 1544 1545 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1546 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1547 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1548 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1549 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1550 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1551 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1552 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1553 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1554 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1555 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1556 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1557 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1558 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1559 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1560 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1561 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1562 }; 1563 1564 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1565 .kind = "ip6gre", 1566 .maxtype = IFLA_GRE_MAX, 1567 .policy = ip6gre_policy, 1568 .priv_size = sizeof(struct ip6_tnl), 1569 .setup = ip6gre_tunnel_setup, 1570 .validate = ip6gre_tunnel_validate, 1571 .newlink = ip6gre_newlink, 1572 .changelink = ip6gre_changelink, 1573 .dellink = ip6gre_dellink, 1574 .get_size = ip6gre_get_size, 1575 .fill_info = ip6gre_fill_info, 1576 .get_link_net = ip6_tnl_get_link_net, 1577 }; 1578 1579 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1580 .kind = "ip6gretap", 1581 .maxtype = IFLA_GRE_MAX, 1582 .policy = ip6gre_policy, 1583 .priv_size = sizeof(struct ip6_tnl), 1584 .setup = ip6gre_tap_setup, 1585 .validate = ip6gre_tap_validate, 1586 .newlink = ip6gre_newlink, 1587 .changelink = ip6gre_changelink, 1588 .get_size = ip6gre_get_size, 1589 .fill_info = ip6gre_fill_info, 1590 .get_link_net = ip6_tnl_get_link_net, 1591 }; 1592 1593 /* 1594 * And now the modules code and kernel interface. 1595 */ 1596 1597 static int __init ip6gre_init(void) 1598 { 1599 int err; 1600 1601 pr_info("GRE over IPv6 tunneling driver\n"); 1602 1603 err = register_pernet_device(&ip6gre_net_ops); 1604 if (err < 0) 1605 return err; 1606 1607 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1608 if (err < 0) { 1609 pr_info("%s: can't add protocol\n", __func__); 1610 goto add_proto_failed; 1611 } 1612 1613 err = rtnl_link_register(&ip6gre_link_ops); 1614 if (err < 0) 1615 goto rtnl_link_failed; 1616 1617 err = rtnl_link_register(&ip6gre_tap_ops); 1618 if (err < 0) 1619 goto tap_ops_failed; 1620 1621 out: 1622 return err; 1623 1624 tap_ops_failed: 1625 rtnl_link_unregister(&ip6gre_link_ops); 1626 rtnl_link_failed: 1627 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1628 add_proto_failed: 1629 unregister_pernet_device(&ip6gre_net_ops); 1630 goto out; 1631 } 1632 1633 static void __exit ip6gre_fini(void) 1634 { 1635 rtnl_link_unregister(&ip6gre_tap_ops); 1636 rtnl_link_unregister(&ip6gre_link_ops); 1637 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1638 unregister_pernet_device(&ip6gre_net_ops); 1639 } 1640 1641 module_init(ip6gre_init); 1642 module_exit(ip6gre_fini); 1643 MODULE_LICENSE("GPL"); 1644 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1645 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1646 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1647 MODULE_ALIAS_RTNL_LINK("ip6gretap"); 1648 MODULE_ALIAS_NETDEV("ip6gre0"); 1649