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 struct net *net = dev_net(skb->dev); 373 const struct gre_base_hdr *greh; 374 const struct ipv6hdr *ipv6h; 375 int grehlen = sizeof(*greh); 376 struct ip6_tnl *t; 377 int key_off = 0; 378 __be16 flags; 379 __be32 key; 380 381 if (!pskb_may_pull(skb, offset + grehlen)) 382 return; 383 greh = (const struct gre_base_hdr *)(skb->data + offset); 384 flags = greh->flags; 385 if (flags & (GRE_VERSION | GRE_ROUTING)) 386 return; 387 if (flags & GRE_CSUM) 388 grehlen += 4; 389 if (flags & GRE_KEY) { 390 key_off = grehlen + offset; 391 grehlen += 4; 392 } 393 394 if (!pskb_may_pull(skb, offset + grehlen)) 395 return; 396 ipv6h = (const struct ipv6hdr *)skb->data; 397 greh = (const struct gre_base_hdr *)(skb->data + offset); 398 key = key_off ? *(__be32 *)(skb->data + key_off) : 0; 399 400 t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, 401 key, greh->protocol); 402 if (!t) 403 return; 404 405 switch (type) { 406 struct ipv6_tlv_tnl_enc_lim *tel; 407 __u32 teli; 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 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 439 return; 440 case NDISC_REDIRECT: 441 ip6_redirect(skb, net, skb->dev->ifindex, 0, 442 sock_net_uid(net, NULL)); 443 return; 444 } 445 446 if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO)) 447 t->err_count++; 448 else 449 t->err_count = 1; 450 t->err_time = jiffies; 451 } 452 453 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi) 454 { 455 const struct ipv6hdr *ipv6h; 456 struct ip6_tnl *tunnel; 457 458 ipv6h = ipv6_hdr(skb); 459 tunnel = ip6gre_tunnel_lookup(skb->dev, 460 &ipv6h->saddr, &ipv6h->daddr, tpi->key, 461 tpi->proto); 462 if (tunnel) { 463 ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error); 464 465 return PACKET_RCVD; 466 } 467 468 return PACKET_REJECT; 469 } 470 471 static int gre_rcv(struct sk_buff *skb) 472 { 473 struct tnl_ptk_info tpi; 474 bool csum_err = false; 475 int hdr_len; 476 477 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0); 478 if (hdr_len < 0) 479 goto drop; 480 481 if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false)) 482 goto drop; 483 484 if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD) 485 return 0; 486 487 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 488 drop: 489 kfree_skb(skb); 490 return 0; 491 } 492 493 static int gre_handle_offloads(struct sk_buff *skb, bool csum) 494 { 495 return iptunnel_handle_offloads(skb, 496 csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); 497 } 498 499 static netdev_tx_t __gre6_xmit(struct sk_buff *skb, 500 struct net_device *dev, __u8 dsfield, 501 struct flowi6 *fl6, int encap_limit, 502 __u32 *pmtu, __be16 proto) 503 { 504 struct ip6_tnl *tunnel = netdev_priv(dev); 505 __be16 protocol; 506 507 if (dev->type == ARPHRD_ETHER) 508 IPCB(skb)->flags = 0; 509 510 if (dev->header_ops && dev->type == ARPHRD_IP6GRE) 511 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr; 512 else 513 fl6->daddr = tunnel->parms.raddr; 514 515 if (tunnel->parms.o_flags & TUNNEL_SEQ) 516 tunnel->o_seqno++; 517 518 /* Push GRE header. */ 519 protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto; 520 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags, 521 protocol, tunnel->parms.o_key, htonl(tunnel->o_seqno)); 522 523 return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu, 524 NEXTHDR_GRE); 525 } 526 527 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) 528 { 529 struct ip6_tnl *t = netdev_priv(dev); 530 const struct iphdr *iph = ip_hdr(skb); 531 int encap_limit = -1; 532 struct flowi6 fl6; 533 __u8 dsfield; 534 __u32 mtu; 535 int err; 536 537 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 538 539 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 540 encap_limit = t->parms.encap_limit; 541 542 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 543 544 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 545 dsfield = ipv4_get_dsfield(iph); 546 else 547 dsfield = ip6_tclass(t->parms.flowinfo); 548 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 549 fl6.flowi6_mark = skb->mark; 550 else 551 fl6.flowi6_mark = t->parms.fwmark; 552 553 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 554 555 err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); 556 if (err) 557 return -1; 558 559 err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, 560 skb->protocol); 561 if (err != 0) { 562 /* XXX: send ICMP error even if DF is not set. */ 563 if (err == -EMSGSIZE) 564 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 565 htonl(mtu)); 566 return -1; 567 } 568 569 return 0; 570 } 571 572 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) 573 { 574 struct ip6_tnl *t = netdev_priv(dev); 575 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 576 int encap_limit = -1; 577 __u16 offset; 578 struct flowi6 fl6; 579 __u8 dsfield; 580 __u32 mtu; 581 int err; 582 583 if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr)) 584 return -1; 585 586 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); 587 /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */ 588 ipv6h = ipv6_hdr(skb); 589 590 if (offset > 0) { 591 struct ipv6_tlv_tnl_enc_lim *tel; 592 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; 593 if (tel->encap_limit == 0) { 594 icmpv6_send(skb, ICMPV6_PARAMPROB, 595 ICMPV6_HDR_FIELD, offset + 2); 596 return -1; 597 } 598 encap_limit = tel->encap_limit - 1; 599 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 600 encap_limit = t->parms.encap_limit; 601 602 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 603 604 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) 605 dsfield = ipv6_get_dsfield(ipv6h); 606 else 607 dsfield = ip6_tclass(t->parms.flowinfo); 608 609 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) 610 fl6.flowlabel |= ip6_flowlabel(ipv6h); 611 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) 612 fl6.flowi6_mark = skb->mark; 613 else 614 fl6.flowi6_mark = t->parms.fwmark; 615 616 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL); 617 618 if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM))) 619 return -1; 620 621 err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, 622 &mtu, skb->protocol); 623 if (err != 0) { 624 if (err == -EMSGSIZE) 625 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); 626 return -1; 627 } 628 629 return 0; 630 } 631 632 /** 633 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own 634 * @t: the outgoing tunnel device 635 * @hdr: IPv6 header from the incoming packet 636 * 637 * Description: 638 * Avoid trivial tunneling loop by checking that tunnel exit-point 639 * doesn't match source of incoming packet. 640 * 641 * Return: 642 * 1 if conflict, 643 * 0 else 644 **/ 645 646 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t, 647 const struct ipv6hdr *hdr) 648 { 649 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); 650 } 651 652 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) 653 { 654 struct ip6_tnl *t = netdev_priv(dev); 655 int encap_limit = -1; 656 struct flowi6 fl6; 657 __u32 mtu; 658 int err; 659 660 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 661 encap_limit = t->parms.encap_limit; 662 663 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); 664 665 err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); 666 if (err) 667 return err; 668 669 err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol); 670 671 return err; 672 } 673 674 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, 675 struct net_device *dev) 676 { 677 struct ip6_tnl *t = netdev_priv(dev); 678 struct net_device_stats *stats = &t->dev->stats; 679 int ret; 680 681 if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr)) 682 goto tx_err; 683 684 switch (skb->protocol) { 685 case htons(ETH_P_IP): 686 ret = ip6gre_xmit_ipv4(skb, dev); 687 break; 688 case htons(ETH_P_IPV6): 689 ret = ip6gre_xmit_ipv6(skb, dev); 690 break; 691 default: 692 ret = ip6gre_xmit_other(skb, dev); 693 break; 694 } 695 696 if (ret < 0) 697 goto tx_err; 698 699 return NETDEV_TX_OK; 700 701 tx_err: 702 stats->tx_errors++; 703 stats->tx_dropped++; 704 kfree_skb(skb); 705 return NETDEV_TX_OK; 706 } 707 708 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu) 709 { 710 struct net_device *dev = t->dev; 711 struct __ip6_tnl_parm *p = &t->parms; 712 struct flowi6 *fl6 = &t->fl.u.ip6; 713 int t_hlen; 714 715 if (dev->type != ARPHRD_ETHER) { 716 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); 717 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); 718 } 719 720 /* Set up flowi template */ 721 fl6->saddr = p->laddr; 722 fl6->daddr = p->raddr; 723 fl6->flowi6_oif = p->link; 724 fl6->flowlabel = 0; 725 fl6->flowi6_proto = IPPROTO_GRE; 726 727 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) 728 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; 729 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) 730 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; 731 732 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); 733 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); 734 735 if (p->flags&IP6_TNL_F_CAP_XMIT && 736 p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER) 737 dev->flags |= IFF_POINTOPOINT; 738 else 739 dev->flags &= ~IFF_POINTOPOINT; 740 741 t->tun_hlen = gre_calc_hlen(t->parms.o_flags); 742 743 t->hlen = t->encap_hlen + t->tun_hlen; 744 745 t_hlen = t->hlen + sizeof(struct ipv6hdr); 746 747 if (p->flags & IP6_TNL_F_CAP_XMIT) { 748 int strict = (ipv6_addr_type(&p->raddr) & 749 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); 750 751 struct rt6_info *rt = rt6_lookup(t->net, 752 &p->raddr, &p->laddr, 753 p->link, strict); 754 755 if (!rt) 756 return; 757 758 if (rt->dst.dev) { 759 dev->hard_header_len = rt->dst.dev->hard_header_len + 760 t_hlen; 761 762 if (set_mtu) { 763 dev->mtu = rt->dst.dev->mtu - t_hlen; 764 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 765 dev->mtu -= 8; 766 if (dev->type == ARPHRD_ETHER) 767 dev->mtu -= ETH_HLEN; 768 769 if (dev->mtu < IPV6_MIN_MTU) 770 dev->mtu = IPV6_MIN_MTU; 771 } 772 } 773 ip6_rt_put(rt); 774 } 775 } 776 777 static int ip6gre_tnl_change(struct ip6_tnl *t, 778 const struct __ip6_tnl_parm *p, int set_mtu) 779 { 780 t->parms.laddr = p->laddr; 781 t->parms.raddr = p->raddr; 782 t->parms.flags = p->flags; 783 t->parms.hop_limit = p->hop_limit; 784 t->parms.encap_limit = p->encap_limit; 785 t->parms.flowinfo = p->flowinfo; 786 t->parms.link = p->link; 787 t->parms.proto = p->proto; 788 t->parms.i_key = p->i_key; 789 t->parms.o_key = p->o_key; 790 t->parms.i_flags = p->i_flags; 791 t->parms.o_flags = p->o_flags; 792 t->parms.fwmark = p->fwmark; 793 dst_cache_reset(&t->dst_cache); 794 ip6gre_tnl_link_config(t, set_mtu); 795 return 0; 796 } 797 798 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p, 799 const struct ip6_tnl_parm2 *u) 800 { 801 p->laddr = u->laddr; 802 p->raddr = u->raddr; 803 p->flags = u->flags; 804 p->hop_limit = u->hop_limit; 805 p->encap_limit = u->encap_limit; 806 p->flowinfo = u->flowinfo; 807 p->link = u->link; 808 p->i_key = u->i_key; 809 p->o_key = u->o_key; 810 p->i_flags = gre_flags_to_tnl_flags(u->i_flags); 811 p->o_flags = gre_flags_to_tnl_flags(u->o_flags); 812 memcpy(p->name, u->name, sizeof(u->name)); 813 } 814 815 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u, 816 const struct __ip6_tnl_parm *p) 817 { 818 u->proto = IPPROTO_GRE; 819 u->laddr = p->laddr; 820 u->raddr = p->raddr; 821 u->flags = p->flags; 822 u->hop_limit = p->hop_limit; 823 u->encap_limit = p->encap_limit; 824 u->flowinfo = p->flowinfo; 825 u->link = p->link; 826 u->i_key = p->i_key; 827 u->o_key = p->o_key; 828 u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags); 829 u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags); 830 memcpy(u->name, p->name, sizeof(u->name)); 831 } 832 833 static int ip6gre_tunnel_ioctl(struct net_device *dev, 834 struct ifreq *ifr, int cmd) 835 { 836 int err = 0; 837 struct ip6_tnl_parm2 p; 838 struct __ip6_tnl_parm p1; 839 struct ip6_tnl *t = netdev_priv(dev); 840 struct net *net = t->net; 841 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 842 843 memset(&p1, 0, sizeof(p1)); 844 845 switch (cmd) { 846 case SIOCGETTUNNEL: 847 if (dev == ign->fb_tunnel_dev) { 848 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 849 err = -EFAULT; 850 break; 851 } 852 ip6gre_tnl_parm_from_user(&p1, &p); 853 t = ip6gre_tunnel_locate(net, &p1, 0); 854 if (!t) 855 t = netdev_priv(dev); 856 } 857 memset(&p, 0, sizeof(p)); 858 ip6gre_tnl_parm_to_user(&p, &t->parms); 859 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 860 err = -EFAULT; 861 break; 862 863 case SIOCADDTUNNEL: 864 case SIOCCHGTUNNEL: 865 err = -EPERM; 866 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 867 goto done; 868 869 err = -EFAULT; 870 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 871 goto done; 872 873 err = -EINVAL; 874 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)) 875 goto done; 876 877 if (!(p.i_flags&GRE_KEY)) 878 p.i_key = 0; 879 if (!(p.o_flags&GRE_KEY)) 880 p.o_key = 0; 881 882 ip6gre_tnl_parm_from_user(&p1, &p); 883 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL); 884 885 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 886 if (t) { 887 if (t->dev != dev) { 888 err = -EEXIST; 889 break; 890 } 891 } else { 892 t = netdev_priv(dev); 893 894 ip6gre_tunnel_unlink(ign, t); 895 synchronize_net(); 896 ip6gre_tnl_change(t, &p1, 1); 897 ip6gre_tunnel_link(ign, t); 898 netdev_state_change(dev); 899 } 900 } 901 902 if (t) { 903 err = 0; 904 905 memset(&p, 0, sizeof(p)); 906 ip6gre_tnl_parm_to_user(&p, &t->parms); 907 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 908 err = -EFAULT; 909 } else 910 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 911 break; 912 913 case SIOCDELTUNNEL: 914 err = -EPERM; 915 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 916 goto done; 917 918 if (dev == ign->fb_tunnel_dev) { 919 err = -EFAULT; 920 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 921 goto done; 922 err = -ENOENT; 923 ip6gre_tnl_parm_from_user(&p1, &p); 924 t = ip6gre_tunnel_locate(net, &p1, 0); 925 if (!t) 926 goto done; 927 err = -EPERM; 928 if (t == netdev_priv(ign->fb_tunnel_dev)) 929 goto done; 930 dev = t->dev; 931 } 932 unregister_netdevice(dev); 933 err = 0; 934 break; 935 936 default: 937 err = -EINVAL; 938 } 939 940 done: 941 return err; 942 } 943 944 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, 945 unsigned short type, const void *daddr, 946 const void *saddr, unsigned int len) 947 { 948 struct ip6_tnl *t = netdev_priv(dev); 949 struct ipv6hdr *ipv6h; 950 __be16 *p; 951 952 ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h)); 953 ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb, 954 t->fl.u.ip6.flowlabel, 955 true, &t->fl.u.ip6)); 956 ipv6h->hop_limit = t->parms.hop_limit; 957 ipv6h->nexthdr = NEXTHDR_GRE; 958 ipv6h->saddr = t->parms.laddr; 959 ipv6h->daddr = t->parms.raddr; 960 961 p = (__be16 *)(ipv6h + 1); 962 p[0] = t->parms.o_flags; 963 p[1] = htons(type); 964 965 /* 966 * Set the source hardware address. 967 */ 968 969 if (saddr) 970 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); 971 if (daddr) 972 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); 973 if (!ipv6_addr_any(&ipv6h->daddr)) 974 return t->hlen; 975 976 return -t->hlen; 977 } 978 979 static const struct header_ops ip6gre_header_ops = { 980 .create = ip6gre_header, 981 }; 982 983 static const struct net_device_ops ip6gre_netdev_ops = { 984 .ndo_init = ip6gre_tunnel_init, 985 .ndo_uninit = ip6gre_tunnel_uninit, 986 .ndo_start_xmit = ip6gre_tunnel_xmit, 987 .ndo_do_ioctl = ip6gre_tunnel_ioctl, 988 .ndo_change_mtu = ip6_tnl_change_mtu, 989 .ndo_get_stats64 = ip_tunnel_get_stats64, 990 .ndo_get_iflink = ip6_tnl_get_iflink, 991 }; 992 993 static void ip6gre_dev_free(struct net_device *dev) 994 { 995 struct ip6_tnl *t = netdev_priv(dev); 996 997 dst_cache_destroy(&t->dst_cache); 998 free_percpu(dev->tstats); 999 } 1000 1001 static void ip6gre_tunnel_setup(struct net_device *dev) 1002 { 1003 dev->netdev_ops = &ip6gre_netdev_ops; 1004 dev->needs_free_netdev = true; 1005 dev->priv_destructor = ip6gre_dev_free; 1006 1007 dev->type = ARPHRD_IP6GRE; 1008 1009 dev->flags |= IFF_NOARP; 1010 dev->addr_len = sizeof(struct in6_addr); 1011 netif_keep_dst(dev); 1012 /* This perm addr will be used as interface identifier by IPv6 */ 1013 dev->addr_assign_type = NET_ADDR_RANDOM; 1014 eth_random_addr(dev->perm_addr); 1015 } 1016 1017 static int ip6gre_tunnel_init_common(struct net_device *dev) 1018 { 1019 struct ip6_tnl *tunnel; 1020 int ret; 1021 int t_hlen; 1022 1023 tunnel = netdev_priv(dev); 1024 1025 tunnel->dev = dev; 1026 tunnel->net = dev_net(dev); 1027 strcpy(tunnel->parms.name, dev->name); 1028 1029 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 1030 if (!dev->tstats) 1031 return -ENOMEM; 1032 1033 ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); 1034 if (ret) { 1035 free_percpu(dev->tstats); 1036 dev->tstats = NULL; 1037 return ret; 1038 } 1039 1040 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 1041 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 1042 t_hlen = tunnel->hlen + sizeof(struct ipv6hdr); 1043 1044 dev->hard_header_len = LL_MAX_HEADER + t_hlen; 1045 dev->mtu = ETH_DATA_LEN - t_hlen; 1046 if (dev->type == ARPHRD_ETHER) 1047 dev->mtu -= ETH_HLEN; 1048 if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) 1049 dev->mtu -= 8; 1050 1051 return 0; 1052 } 1053 1054 static int ip6gre_tunnel_init(struct net_device *dev) 1055 { 1056 struct ip6_tnl *tunnel; 1057 int ret; 1058 1059 ret = ip6gre_tunnel_init_common(dev); 1060 if (ret) 1061 return ret; 1062 1063 tunnel = netdev_priv(dev); 1064 1065 memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr)); 1066 memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr)); 1067 1068 if (ipv6_addr_any(&tunnel->parms.raddr)) 1069 dev->header_ops = &ip6gre_header_ops; 1070 1071 return 0; 1072 } 1073 1074 static void ip6gre_fb_tunnel_init(struct net_device *dev) 1075 { 1076 struct ip6_tnl *tunnel = netdev_priv(dev); 1077 1078 tunnel->dev = dev; 1079 tunnel->net = dev_net(dev); 1080 strcpy(tunnel->parms.name, dev->name); 1081 1082 tunnel->hlen = sizeof(struct ipv6hdr) + 4; 1083 1084 dev_hold(dev); 1085 } 1086 1087 1088 static struct inet6_protocol ip6gre_protocol __read_mostly = { 1089 .handler = gre_rcv, 1090 .err_handler = ip6gre_err, 1091 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1092 }; 1093 1094 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head) 1095 { 1096 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1097 struct net_device *dev, *aux; 1098 int prio; 1099 1100 for_each_netdev_safe(net, dev, aux) 1101 if (dev->rtnl_link_ops == &ip6gre_link_ops || 1102 dev->rtnl_link_ops == &ip6gre_tap_ops) 1103 unregister_netdevice_queue(dev, head); 1104 1105 for (prio = 0; prio < 4; prio++) { 1106 int h; 1107 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) { 1108 struct ip6_tnl *t; 1109 1110 t = rtnl_dereference(ign->tunnels[prio][h]); 1111 1112 while (t) { 1113 /* If dev is in the same netns, it has already 1114 * been added to the list by the previous loop. 1115 */ 1116 if (!net_eq(dev_net(t->dev), net)) 1117 unregister_netdevice_queue(t->dev, 1118 head); 1119 t = rtnl_dereference(t->next); 1120 } 1121 } 1122 } 1123 } 1124 1125 static int __net_init ip6gre_init_net(struct net *net) 1126 { 1127 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1128 int err; 1129 1130 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0", 1131 NET_NAME_UNKNOWN, 1132 ip6gre_tunnel_setup); 1133 if (!ign->fb_tunnel_dev) { 1134 err = -ENOMEM; 1135 goto err_alloc_dev; 1136 } 1137 dev_net_set(ign->fb_tunnel_dev, net); 1138 /* FB netdevice is special: we have one, and only one per netns. 1139 * Allowing to move it to another netns is clearly unsafe. 1140 */ 1141 ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; 1142 1143 1144 ip6gre_fb_tunnel_init(ign->fb_tunnel_dev); 1145 ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops; 1146 1147 err = register_netdev(ign->fb_tunnel_dev); 1148 if (err) 1149 goto err_reg_dev; 1150 1151 rcu_assign_pointer(ign->tunnels_wc[0], 1152 netdev_priv(ign->fb_tunnel_dev)); 1153 return 0; 1154 1155 err_reg_dev: 1156 free_netdev(ign->fb_tunnel_dev); 1157 err_alloc_dev: 1158 return err; 1159 } 1160 1161 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list) 1162 { 1163 struct net *net; 1164 LIST_HEAD(list); 1165 1166 rtnl_lock(); 1167 list_for_each_entry(net, net_list, exit_list) 1168 ip6gre_destroy_tunnels(net, &list); 1169 unregister_netdevice_many(&list); 1170 rtnl_unlock(); 1171 } 1172 1173 static struct pernet_operations ip6gre_net_ops = { 1174 .init = ip6gre_init_net, 1175 .exit_batch = ip6gre_exit_batch_net, 1176 .id = &ip6gre_net_id, 1177 .size = sizeof(struct ip6gre_net), 1178 }; 1179 1180 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1181 struct netlink_ext_ack *extack) 1182 { 1183 __be16 flags; 1184 1185 if (!data) 1186 return 0; 1187 1188 flags = 0; 1189 if (data[IFLA_GRE_IFLAGS]) 1190 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1191 if (data[IFLA_GRE_OFLAGS]) 1192 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1193 if (flags & (GRE_VERSION|GRE_ROUTING)) 1194 return -EINVAL; 1195 1196 return 0; 1197 } 1198 1199 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1200 struct netlink_ext_ack *extack) 1201 { 1202 struct in6_addr daddr; 1203 1204 if (tb[IFLA_ADDRESS]) { 1205 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1206 return -EINVAL; 1207 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1208 return -EADDRNOTAVAIL; 1209 } 1210 1211 if (!data) 1212 goto out; 1213 1214 if (data[IFLA_GRE_REMOTE]) { 1215 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1216 if (ipv6_addr_any(&daddr)) 1217 return -EINVAL; 1218 } 1219 1220 out: 1221 return ip6gre_tunnel_validate(tb, data, extack); 1222 } 1223 1224 1225 static void ip6gre_netlink_parms(struct nlattr *data[], 1226 struct __ip6_tnl_parm *parms) 1227 { 1228 memset(parms, 0, sizeof(*parms)); 1229 1230 if (!data) 1231 return; 1232 1233 if (data[IFLA_GRE_LINK]) 1234 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1235 1236 if (data[IFLA_GRE_IFLAGS]) 1237 parms->i_flags = gre_flags_to_tnl_flags( 1238 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1239 1240 if (data[IFLA_GRE_OFLAGS]) 1241 parms->o_flags = gre_flags_to_tnl_flags( 1242 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1243 1244 if (data[IFLA_GRE_IKEY]) 1245 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1246 1247 if (data[IFLA_GRE_OKEY]) 1248 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1249 1250 if (data[IFLA_GRE_LOCAL]) 1251 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]); 1252 1253 if (data[IFLA_GRE_REMOTE]) 1254 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]); 1255 1256 if (data[IFLA_GRE_TTL]) 1257 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]); 1258 1259 if (data[IFLA_GRE_ENCAP_LIMIT]) 1260 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]); 1261 1262 if (data[IFLA_GRE_FLOWINFO]) 1263 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]); 1264 1265 if (data[IFLA_GRE_FLAGS]) 1266 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]); 1267 1268 if (data[IFLA_GRE_FWMARK]) 1269 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1270 } 1271 1272 static int ip6gre_tap_init(struct net_device *dev) 1273 { 1274 struct ip6_tnl *tunnel; 1275 int ret; 1276 1277 ret = ip6gre_tunnel_init_common(dev); 1278 if (ret) 1279 return ret; 1280 1281 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1282 1283 tunnel = netdev_priv(dev); 1284 1285 ip6gre_tnl_link_config(tunnel, 1); 1286 1287 return 0; 1288 } 1289 1290 static const struct net_device_ops ip6gre_tap_netdev_ops = { 1291 .ndo_init = ip6gre_tap_init, 1292 .ndo_uninit = ip6gre_tunnel_uninit, 1293 .ndo_start_xmit = ip6gre_tunnel_xmit, 1294 .ndo_set_mac_address = eth_mac_addr, 1295 .ndo_validate_addr = eth_validate_addr, 1296 .ndo_change_mtu = ip6_tnl_change_mtu, 1297 .ndo_get_stats64 = ip_tunnel_get_stats64, 1298 .ndo_get_iflink = ip6_tnl_get_iflink, 1299 }; 1300 1301 #define GRE6_FEATURES (NETIF_F_SG | \ 1302 NETIF_F_FRAGLIST | \ 1303 NETIF_F_HIGHDMA | \ 1304 NETIF_F_HW_CSUM) 1305 1306 static void ip6gre_tap_setup(struct net_device *dev) 1307 { 1308 1309 ether_setup(dev); 1310 1311 dev->netdev_ops = &ip6gre_tap_netdev_ops; 1312 dev->needs_free_netdev = true; 1313 dev->priv_destructor = ip6gre_dev_free; 1314 1315 dev->features |= NETIF_F_NETNS_LOCAL; 1316 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1317 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1318 netif_keep_dst(dev); 1319 } 1320 1321 static bool ip6gre_netlink_encap_parms(struct nlattr *data[], 1322 struct ip_tunnel_encap *ipencap) 1323 { 1324 bool ret = false; 1325 1326 memset(ipencap, 0, sizeof(*ipencap)); 1327 1328 if (!data) 1329 return ret; 1330 1331 if (data[IFLA_GRE_ENCAP_TYPE]) { 1332 ret = true; 1333 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1334 } 1335 1336 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1337 ret = true; 1338 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1339 } 1340 1341 if (data[IFLA_GRE_ENCAP_SPORT]) { 1342 ret = true; 1343 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1344 } 1345 1346 if (data[IFLA_GRE_ENCAP_DPORT]) { 1347 ret = true; 1348 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1349 } 1350 1351 return ret; 1352 } 1353 1354 static int ip6gre_newlink(struct net *src_net, struct net_device *dev, 1355 struct nlattr *tb[], struct nlattr *data[], 1356 struct netlink_ext_ack *extack) 1357 { 1358 struct ip6_tnl *nt; 1359 struct net *net = dev_net(dev); 1360 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1361 struct ip_tunnel_encap ipencap; 1362 int err; 1363 1364 nt = netdev_priv(dev); 1365 1366 if (ip6gre_netlink_encap_parms(data, &ipencap)) { 1367 int err = ip6_tnl_encap_setup(nt, &ipencap); 1368 1369 if (err < 0) 1370 return err; 1371 } 1372 1373 ip6gre_netlink_parms(data, &nt->parms); 1374 1375 if (ip6gre_tunnel_find(net, &nt->parms, dev->type)) 1376 return -EEXIST; 1377 1378 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) 1379 eth_hw_addr_random(dev); 1380 1381 nt->dev = dev; 1382 nt->net = dev_net(dev); 1383 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]); 1384 1385 dev->features |= GRE6_FEATURES; 1386 dev->hw_features |= GRE6_FEATURES; 1387 1388 if (!(nt->parms.o_flags & TUNNEL_SEQ)) { 1389 /* TCP offload with GRE SEQ is not supported, nor 1390 * can we support 2 levels of outer headers requiring 1391 * an update. 1392 */ 1393 if (!(nt->parms.o_flags & TUNNEL_CSUM) || 1394 (nt->encap.type == TUNNEL_ENCAP_NONE)) { 1395 dev->features |= NETIF_F_GSO_SOFTWARE; 1396 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 1397 } 1398 1399 /* Can use a lockless transmit, unless we generate 1400 * output sequences 1401 */ 1402 dev->features |= NETIF_F_LLTX; 1403 } 1404 1405 err = register_netdevice(dev); 1406 if (err) 1407 goto out; 1408 1409 dev_hold(dev); 1410 ip6gre_tunnel_link(ign, nt); 1411 1412 out: 1413 return err; 1414 } 1415 1416 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[], 1417 struct nlattr *data[], 1418 struct netlink_ext_ack *extack) 1419 { 1420 struct ip6_tnl *t, *nt = netdev_priv(dev); 1421 struct net *net = nt->net; 1422 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1423 struct __ip6_tnl_parm p; 1424 struct ip_tunnel_encap ipencap; 1425 1426 if (dev == ign->fb_tunnel_dev) 1427 return -EINVAL; 1428 1429 if (ip6gre_netlink_encap_parms(data, &ipencap)) { 1430 int err = ip6_tnl_encap_setup(nt, &ipencap); 1431 1432 if (err < 0) 1433 return err; 1434 } 1435 1436 ip6gre_netlink_parms(data, &p); 1437 1438 t = ip6gre_tunnel_locate(net, &p, 0); 1439 1440 if (t) { 1441 if (t->dev != dev) 1442 return -EEXIST; 1443 } else { 1444 t = nt; 1445 } 1446 1447 ip6gre_tunnel_unlink(ign, t); 1448 ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]); 1449 ip6gre_tunnel_link(ign, t); 1450 return 0; 1451 } 1452 1453 static void ip6gre_dellink(struct net_device *dev, struct list_head *head) 1454 { 1455 struct net *net = dev_net(dev); 1456 struct ip6gre_net *ign = net_generic(net, ip6gre_net_id); 1457 1458 if (dev != ign->fb_tunnel_dev) 1459 unregister_netdevice_queue(dev, head); 1460 } 1461 1462 static size_t ip6gre_get_size(const struct net_device *dev) 1463 { 1464 return 1465 /* IFLA_GRE_LINK */ 1466 nla_total_size(4) + 1467 /* IFLA_GRE_IFLAGS */ 1468 nla_total_size(2) + 1469 /* IFLA_GRE_OFLAGS */ 1470 nla_total_size(2) + 1471 /* IFLA_GRE_IKEY */ 1472 nla_total_size(4) + 1473 /* IFLA_GRE_OKEY */ 1474 nla_total_size(4) + 1475 /* IFLA_GRE_LOCAL */ 1476 nla_total_size(sizeof(struct in6_addr)) + 1477 /* IFLA_GRE_REMOTE */ 1478 nla_total_size(sizeof(struct in6_addr)) + 1479 /* IFLA_GRE_TTL */ 1480 nla_total_size(1) + 1481 /* IFLA_GRE_ENCAP_LIMIT */ 1482 nla_total_size(1) + 1483 /* IFLA_GRE_FLOWINFO */ 1484 nla_total_size(4) + 1485 /* IFLA_GRE_FLAGS */ 1486 nla_total_size(4) + 1487 /* IFLA_GRE_ENCAP_TYPE */ 1488 nla_total_size(2) + 1489 /* IFLA_GRE_ENCAP_FLAGS */ 1490 nla_total_size(2) + 1491 /* IFLA_GRE_ENCAP_SPORT */ 1492 nla_total_size(2) + 1493 /* IFLA_GRE_ENCAP_DPORT */ 1494 nla_total_size(2) + 1495 /* IFLA_GRE_FWMARK */ 1496 nla_total_size(4) + 1497 0; 1498 } 1499 1500 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1501 { 1502 struct ip6_tnl *t = netdev_priv(dev); 1503 struct __ip6_tnl_parm *p = &t->parms; 1504 1505 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1506 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1507 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1508 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1509 gre_tnl_flags_to_gre_flags(p->o_flags)) || 1510 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1511 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1512 nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) || 1513 nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) || 1514 nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) || 1515 nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) || 1516 nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) || 1517 nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) || 1518 nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark)) 1519 goto nla_put_failure; 1520 1521 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1522 t->encap.type) || 1523 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1524 t->encap.sport) || 1525 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1526 t->encap.dport) || 1527 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1528 t->encap.flags)) 1529 goto nla_put_failure; 1530 1531 return 0; 1532 1533 nla_put_failure: 1534 return -EMSGSIZE; 1535 } 1536 1537 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = { 1538 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1539 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1540 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1541 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1542 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1543 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) }, 1544 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) }, 1545 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1546 [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 }, 1547 [IFLA_GRE_FLOWINFO] = { .type = NLA_U32 }, 1548 [IFLA_GRE_FLAGS] = { .type = NLA_U32 }, 1549 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1550 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1551 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1552 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1553 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1554 }; 1555 1556 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { 1557 .kind = "ip6gre", 1558 .maxtype = IFLA_GRE_MAX, 1559 .policy = ip6gre_policy, 1560 .priv_size = sizeof(struct ip6_tnl), 1561 .setup = ip6gre_tunnel_setup, 1562 .validate = ip6gre_tunnel_validate, 1563 .newlink = ip6gre_newlink, 1564 .changelink = ip6gre_changelink, 1565 .dellink = ip6gre_dellink, 1566 .get_size = ip6gre_get_size, 1567 .fill_info = ip6gre_fill_info, 1568 .get_link_net = ip6_tnl_get_link_net, 1569 }; 1570 1571 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = { 1572 .kind = "ip6gretap", 1573 .maxtype = IFLA_GRE_MAX, 1574 .policy = ip6gre_policy, 1575 .priv_size = sizeof(struct ip6_tnl), 1576 .setup = ip6gre_tap_setup, 1577 .validate = ip6gre_tap_validate, 1578 .newlink = ip6gre_newlink, 1579 .changelink = ip6gre_changelink, 1580 .get_size = ip6gre_get_size, 1581 .fill_info = ip6gre_fill_info, 1582 .get_link_net = ip6_tnl_get_link_net, 1583 }; 1584 1585 /* 1586 * And now the modules code and kernel interface. 1587 */ 1588 1589 static int __init ip6gre_init(void) 1590 { 1591 int err; 1592 1593 pr_info("GRE over IPv6 tunneling driver\n"); 1594 1595 err = register_pernet_device(&ip6gre_net_ops); 1596 if (err < 0) 1597 return err; 1598 1599 err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE); 1600 if (err < 0) { 1601 pr_info("%s: can't add protocol\n", __func__); 1602 goto add_proto_failed; 1603 } 1604 1605 err = rtnl_link_register(&ip6gre_link_ops); 1606 if (err < 0) 1607 goto rtnl_link_failed; 1608 1609 err = rtnl_link_register(&ip6gre_tap_ops); 1610 if (err < 0) 1611 goto tap_ops_failed; 1612 1613 out: 1614 return err; 1615 1616 tap_ops_failed: 1617 rtnl_link_unregister(&ip6gre_link_ops); 1618 rtnl_link_failed: 1619 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1620 add_proto_failed: 1621 unregister_pernet_device(&ip6gre_net_ops); 1622 goto out; 1623 } 1624 1625 static void __exit ip6gre_fini(void) 1626 { 1627 rtnl_link_unregister(&ip6gre_tap_ops); 1628 rtnl_link_unregister(&ip6gre_link_ops); 1629 inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE); 1630 unregister_pernet_device(&ip6gre_net_ops); 1631 } 1632 1633 module_init(ip6gre_init); 1634 module_exit(ip6gre_fini); 1635 MODULE_LICENSE("GPL"); 1636 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); 1637 MODULE_DESCRIPTION("GRE over IPv6 tunneling device"); 1638 MODULE_ALIAS_RTNL_LINK("ip6gre"); 1639 MODULE_ALIAS_RTNL_LINK("ip6gretap"); 1640 MODULE_ALIAS_NETDEV("ip6gre0"); 1641