1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Linux NET3: GRE over IP protocol decoder. 4 * 5 * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru) 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10 #include <linux/capability.h> 11 #include <linux/module.h> 12 #include <linux/types.h> 13 #include <linux/kernel.h> 14 #include <linux/slab.h> 15 #include <linux/uaccess.h> 16 #include <linux/skbuff.h> 17 #include <linux/netdevice.h> 18 #include <linux/in.h> 19 #include <linux/tcp.h> 20 #include <linux/udp.h> 21 #include <linux/if_arp.h> 22 #include <linux/if_vlan.h> 23 #include <linux/init.h> 24 #include <linux/in6.h> 25 #include <linux/inetdevice.h> 26 #include <linux/igmp.h> 27 #include <linux/netfilter_ipv4.h> 28 #include <linux/etherdevice.h> 29 #include <linux/if_ether.h> 30 31 #include <net/flow.h> 32 #include <net/sock.h> 33 #include <net/ip.h> 34 #include <net/icmp.h> 35 #include <net/protocol.h> 36 #include <net/ip_tunnels.h> 37 #include <net/arp.h> 38 #include <net/checksum.h> 39 #include <net/dsfield.h> 40 #include <net/inet_ecn.h> 41 #include <net/xfrm.h> 42 #include <net/net_namespace.h> 43 #include <net/netns/generic.h> 44 #include <net/rtnetlink.h> 45 #include <net/gre.h> 46 #include <net/dst_metadata.h> 47 #include <net/erspan.h> 48 49 /* 50 Problems & solutions 51 -------------------- 52 53 1. The most important issue is detecting local dead loops. 54 They would cause complete host lockup in transmit, which 55 would be "resolved" by stack overflow or, if queueing is enabled, 56 with infinite looping in net_bh. 57 58 We cannot track such dead loops during route installation, 59 it is infeasible task. The most general solutions would be 60 to keep skb->encapsulation counter (sort of local ttl), 61 and silently drop packet when it expires. It is a good 62 solution, but it supposes maintaining new variable in ALL 63 skb, even if no tunneling is used. 64 65 Current solution: xmit_recursion breaks dead loops. This is a percpu 66 counter, since when we enter the first ndo_xmit(), cpu migration is 67 forbidden. We force an exit if this counter reaches RECURSION_LIMIT 68 69 2. Networking dead loops would not kill routers, but would really 70 kill network. IP hop limit plays role of "t->recursion" in this case, 71 if we copy it from packet being encapsulated to upper header. 72 It is very good solution, but it introduces two problems: 73 74 - Routing protocols, using packets with ttl=1 (OSPF, RIP2), 75 do not work over tunnels. 76 - traceroute does not work. I planned to relay ICMP from tunnel, 77 so that this problem would be solved and traceroute output 78 would even more informative. This idea appeared to be wrong: 79 only Linux complies to rfc1812 now (yes, guys, Linux is the only 80 true router now :-)), all routers (at least, in neighbourhood of mine) 81 return only 8 bytes of payload. It is the end. 82 83 Hence, if we want that OSPF worked or traceroute said something reasonable, 84 we should search for another solution. 85 86 One of them is to parse packet trying to detect inner encapsulation 87 made by our node. It is difficult or even impossible, especially, 88 taking into account fragmentation. TO be short, ttl is not solution at all. 89 90 Current solution: The solution was UNEXPECTEDLY SIMPLE. 91 We force DF flag on tunnels with preconfigured hop limit, 92 that is ALL. :-) Well, it does not remove the problem completely, 93 but exponential growth of network traffic is changed to linear 94 (branches, that exceed pmtu are pruned) and tunnel mtu 95 rapidly degrades to value <68, where looping stops. 96 Yes, it is not good if there exists a router in the loop, 97 which does not force DF, even when encapsulating packets have DF set. 98 But it is not our problem! Nobody could accuse us, we made 99 all that we could make. Even if it is your gated who injected 100 fatal route to network, even if it were you who configured 101 fatal static route: you are innocent. :-) 102 103 Alexey Kuznetsov. 104 */ 105 106 static bool log_ecn_error = true; 107 module_param(log_ecn_error, bool, 0644); 108 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 109 110 static struct rtnl_link_ops ipgre_link_ops __read_mostly; 111 static const struct header_ops ipgre_header_ops; 112 113 static int ipgre_tunnel_init(struct net_device *dev); 114 static void erspan_build_header(struct sk_buff *skb, 115 u32 id, u32 index, 116 bool truncate, bool is_ipv4); 117 118 static unsigned int ipgre_net_id __read_mostly; 119 static unsigned int gre_tap_net_id __read_mostly; 120 static unsigned int erspan_net_id __read_mostly; 121 122 static int ipgre_err(struct sk_buff *skb, u32 info, 123 const struct tnl_ptk_info *tpi) 124 { 125 126 /* All the routers (except for Linux) return only 127 8 bytes of packet payload. It means, that precise relaying of 128 ICMP in the real Internet is absolutely infeasible. 129 130 Moreover, Cisco "wise men" put GRE key to the third word 131 in GRE header. It makes impossible maintaining even soft 132 state for keyed GRE tunnels with enabled checksum. Tell 133 them "thank you". 134 135 Well, I wonder, rfc1812 was written by Cisco employee, 136 what the hell these idiots break standards established 137 by themselves??? 138 */ 139 struct net *net = dev_net(skb->dev); 140 struct ip_tunnel_net *itn; 141 const struct iphdr *iph; 142 const int type = icmp_hdr(skb)->type; 143 const int code = icmp_hdr(skb)->code; 144 struct ip_tunnel *t; 145 146 if (tpi->proto == htons(ETH_P_TEB)) 147 itn = net_generic(net, gre_tap_net_id); 148 else if (tpi->proto == htons(ETH_P_ERSPAN) || 149 tpi->proto == htons(ETH_P_ERSPAN2)) 150 itn = net_generic(net, erspan_net_id); 151 else 152 itn = net_generic(net, ipgre_net_id); 153 154 iph = (const struct iphdr *)(icmp_hdr(skb) + 1); 155 t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, 156 iph->daddr, iph->saddr, tpi->key); 157 158 if (!t) 159 return -ENOENT; 160 161 switch (type) { 162 default: 163 case ICMP_PARAMETERPROB: 164 return 0; 165 166 case ICMP_DEST_UNREACH: 167 switch (code) { 168 case ICMP_SR_FAILED: 169 case ICMP_PORT_UNREACH: 170 /* Impossible event. */ 171 return 0; 172 default: 173 /* All others are translated to HOST_UNREACH. 174 rfc2003 contains "deep thoughts" about NET_UNREACH, 175 I believe they are just ether pollution. --ANK 176 */ 177 break; 178 } 179 break; 180 181 case ICMP_TIME_EXCEEDED: 182 if (code != ICMP_EXC_TTL) 183 return 0; 184 break; 185 186 case ICMP_REDIRECT: 187 break; 188 } 189 190 #if IS_ENABLED(CONFIG_IPV6) 191 if (tpi->proto == htons(ETH_P_IPV6)) { 192 unsigned int data_len = 0; 193 194 if (type == ICMP_TIME_EXCEEDED) 195 data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */ 196 197 if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len, 198 type, data_len)) 199 return 0; 200 } 201 #endif 202 203 if (t->parms.iph.daddr == 0 || 204 ipv4_is_multicast(t->parms.iph.daddr)) 205 return 0; 206 207 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) 208 return 0; 209 210 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) 211 t->err_count++; 212 else 213 t->err_count = 1; 214 t->err_time = jiffies; 215 216 return 0; 217 } 218 219 static void gre_err(struct sk_buff *skb, u32 info) 220 { 221 /* All the routers (except for Linux) return only 222 * 8 bytes of packet payload. It means, that precise relaying of 223 * ICMP in the real Internet is absolutely infeasible. 224 * 225 * Moreover, Cisco "wise men" put GRE key to the third word 226 * in GRE header. It makes impossible maintaining even soft 227 * state for keyed 228 * GRE tunnels with enabled checksum. Tell them "thank you". 229 * 230 * Well, I wonder, rfc1812 was written by Cisco employee, 231 * what the hell these idiots break standards established 232 * by themselves??? 233 */ 234 235 const struct iphdr *iph = (struct iphdr *)skb->data; 236 const int type = icmp_hdr(skb)->type; 237 const int code = icmp_hdr(skb)->code; 238 struct tnl_ptk_info tpi; 239 240 if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IP), 241 iph->ihl * 4) < 0) 242 return; 243 244 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { 245 ipv4_update_pmtu(skb, dev_net(skb->dev), info, 246 skb->dev->ifindex, IPPROTO_GRE); 247 return; 248 } 249 if (type == ICMP_REDIRECT) { 250 ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex, 251 IPPROTO_GRE); 252 return; 253 } 254 255 ipgre_err(skb, info, &tpi); 256 } 257 258 static bool is_erspan_type1(int gre_hdr_len) 259 { 260 /* Both ERSPAN type I (version 0) and type II (version 1) use 261 * protocol 0x88BE, but the type I has only 4-byte GRE header, 262 * while type II has 8-byte. 263 */ 264 return gre_hdr_len == 4; 265 } 266 267 static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, 268 int gre_hdr_len) 269 { 270 struct net *net = dev_net(skb->dev); 271 struct metadata_dst *tun_dst = NULL; 272 struct erspan_base_hdr *ershdr; 273 IP_TUNNEL_DECLARE_FLAGS(flags); 274 struct ip_tunnel_net *itn; 275 struct ip_tunnel *tunnel; 276 const struct iphdr *iph; 277 struct erspan_md2 *md2; 278 int ver; 279 int len; 280 281 ip_tunnel_flags_copy(flags, tpi->flags); 282 283 itn = net_generic(net, erspan_net_id); 284 iph = ip_hdr(skb); 285 if (is_erspan_type1(gre_hdr_len)) { 286 ver = 0; 287 __set_bit(IP_TUNNEL_NO_KEY_BIT, flags); 288 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, 289 iph->saddr, iph->daddr, 0); 290 } else { 291 if (unlikely(!pskb_may_pull(skb, 292 gre_hdr_len + sizeof(*ershdr)))) 293 return PACKET_REJECT; 294 295 ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); 296 ver = ershdr->ver; 297 iph = ip_hdr(skb); 298 __set_bit(IP_TUNNEL_KEY_BIT, flags); 299 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, 300 iph->saddr, iph->daddr, tpi->key); 301 } 302 303 if (tunnel) { 304 if (is_erspan_type1(gre_hdr_len)) 305 len = gre_hdr_len; 306 else 307 len = gre_hdr_len + erspan_hdr_len(ver); 308 309 if (unlikely(!pskb_may_pull(skb, len))) 310 return PACKET_REJECT; 311 312 if (__iptunnel_pull_header(skb, 313 len, 314 htons(ETH_P_TEB), 315 false, false) < 0) 316 goto drop; 317 318 if (tunnel->collect_md) { 319 struct erspan_metadata *pkt_md, *md; 320 struct ip_tunnel_info *info; 321 unsigned char *gh; 322 __be64 tun_id; 323 324 __set_bit(IP_TUNNEL_KEY_BIT, tpi->flags); 325 ip_tunnel_flags_copy(flags, tpi->flags); 326 tun_id = key32_to_tunnel_id(tpi->key); 327 328 tun_dst = ip_tun_rx_dst(skb, flags, 329 tun_id, sizeof(*md)); 330 if (!tun_dst) 331 return PACKET_REJECT; 332 333 /* MUST set options_len before referencing options */ 334 info = &tun_dst->u.tun_info; 335 info->options_len = sizeof(*md); 336 337 /* skb can be uncloned in __iptunnel_pull_header, so 338 * old pkt_md is no longer valid and we need to reset 339 * it 340 */ 341 gh = skb_network_header(skb) + 342 skb_network_header_len(skb); 343 pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len + 344 sizeof(*ershdr)); 345 md = ip_tunnel_info_opts(&tun_dst->u.tun_info); 346 md->version = ver; 347 md2 = &md->u.md2; 348 memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE : 349 ERSPAN_V2_MDSIZE); 350 351 __set_bit(IP_TUNNEL_ERSPAN_OPT_BIT, 352 info->key.tun_flags); 353 } 354 355 skb_reset_mac_header(skb); 356 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); 357 return PACKET_RCVD; 358 } 359 return PACKET_REJECT; 360 361 drop: 362 kfree_skb(skb); 363 return PACKET_RCVD; 364 } 365 366 static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, 367 struct ip_tunnel_net *itn, int hdr_len, bool raw_proto) 368 { 369 struct metadata_dst *tun_dst = NULL; 370 const struct iphdr *iph; 371 struct ip_tunnel *tunnel; 372 373 iph = ip_hdr(skb); 374 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, 375 iph->saddr, iph->daddr, tpi->key); 376 377 if (tunnel) { 378 const struct iphdr *tnl_params; 379 380 if (__iptunnel_pull_header(skb, hdr_len, tpi->proto, 381 raw_proto, false) < 0) 382 goto drop; 383 384 /* Special case for ipgre_header_parse(), which expects the 385 * mac_header to point to the outer IP header. 386 */ 387 if (tunnel->dev->header_ops == &ipgre_header_ops) 388 skb_pop_mac_header(skb); 389 else 390 skb_reset_mac_header(skb); 391 392 tnl_params = &tunnel->parms.iph; 393 if (tunnel->collect_md || tnl_params->daddr == 0) { 394 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 395 __be64 tun_id; 396 397 __set_bit(IP_TUNNEL_CSUM_BIT, flags); 398 __set_bit(IP_TUNNEL_KEY_BIT, flags); 399 ip_tunnel_flags_and(flags, tpi->flags, flags); 400 401 tun_id = key32_to_tunnel_id(tpi->key); 402 tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0); 403 if (!tun_dst) 404 return PACKET_REJECT; 405 } 406 407 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); 408 return PACKET_RCVD; 409 } 410 return PACKET_NEXT; 411 412 drop: 413 kfree_skb(skb); 414 return PACKET_RCVD; 415 } 416 417 static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, 418 int hdr_len) 419 { 420 struct net *net = dev_net(skb->dev); 421 struct ip_tunnel_net *itn; 422 int res; 423 424 if (tpi->proto == htons(ETH_P_TEB)) 425 itn = net_generic(net, gre_tap_net_id); 426 else 427 itn = net_generic(net, ipgre_net_id); 428 429 res = __ipgre_rcv(skb, tpi, itn, hdr_len, false); 430 if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) { 431 /* ipgre tunnels in collect metadata mode should receive 432 * also ETH_P_TEB traffic. 433 */ 434 itn = net_generic(net, ipgre_net_id); 435 res = __ipgre_rcv(skb, tpi, itn, hdr_len, true); 436 } 437 return res; 438 } 439 440 static int gre_rcv(struct sk_buff *skb) 441 { 442 struct tnl_ptk_info tpi; 443 bool csum_err = false; 444 int hdr_len; 445 446 #ifdef CONFIG_NET_IPGRE_BROADCAST 447 if (ipv4_is_multicast(ip_hdr(skb)->daddr)) { 448 /* Looped back packet, drop it! */ 449 if (rt_is_output_route(skb_rtable(skb))) 450 goto drop; 451 } 452 #endif 453 454 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0); 455 if (hdr_len < 0) 456 goto drop; 457 458 if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) || 459 tpi.proto == htons(ETH_P_ERSPAN2))) { 460 if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) 461 return 0; 462 goto out; 463 } 464 465 if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) 466 return 0; 467 468 out: 469 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); 470 drop: 471 kfree_skb(skb); 472 return 0; 473 } 474 475 static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, 476 const struct iphdr *tnl_params, 477 __be16 proto) 478 { 479 struct ip_tunnel *tunnel = netdev_priv(dev); 480 IP_TUNNEL_DECLARE_FLAGS(flags); 481 482 ip_tunnel_flags_copy(flags, tunnel->parms.o_flags); 483 484 /* Push GRE header. */ 485 gre_build_header(skb, tunnel->tun_hlen, 486 flags, proto, tunnel->parms.o_key, 487 test_bit(IP_TUNNEL_SEQ_BIT, flags) ? 488 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); 489 490 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol); 491 } 492 493 static int gre_handle_offloads(struct sk_buff *skb, bool csum) 494 { 495 return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); 496 } 497 498 static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev, 499 __be16 proto) 500 { 501 struct ip_tunnel *tunnel = netdev_priv(dev); 502 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 503 struct ip_tunnel_info *tun_info; 504 const struct ip_tunnel_key *key; 505 int tunnel_hlen; 506 507 tun_info = skb_tunnel_info(skb); 508 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 509 ip_tunnel_info_af(tun_info) != AF_INET)) 510 goto err_free_skb; 511 512 key = &tun_info->key; 513 tunnel_hlen = gre_calc_hlen(key->tun_flags); 514 515 if (skb_cow_head(skb, dev->needed_headroom)) 516 goto err_free_skb; 517 518 /* Push Tunnel header. */ 519 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 520 tunnel->parms.o_flags))) 521 goto err_free_skb; 522 523 __set_bit(IP_TUNNEL_CSUM_BIT, flags); 524 __set_bit(IP_TUNNEL_KEY_BIT, flags); 525 __set_bit(IP_TUNNEL_SEQ_BIT, flags); 526 ip_tunnel_flags_and(flags, tun_info->key.tun_flags, flags); 527 528 gre_build_header(skb, tunnel_hlen, flags, proto, 529 tunnel_id_to_key32(tun_info->key.tun_id), 530 test_bit(IP_TUNNEL_SEQ_BIT, flags) ? 531 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); 532 533 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); 534 535 return; 536 537 err_free_skb: 538 kfree_skb(skb); 539 DEV_STATS_INC(dev, tx_dropped); 540 } 541 542 static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev) 543 { 544 struct ip_tunnel *tunnel = netdev_priv(dev); 545 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 546 struct ip_tunnel_info *tun_info; 547 const struct ip_tunnel_key *key; 548 struct erspan_metadata *md; 549 bool truncate = false; 550 __be16 proto; 551 int tunnel_hlen; 552 int version; 553 int nhoff; 554 555 tun_info = skb_tunnel_info(skb); 556 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 557 ip_tunnel_info_af(tun_info) != AF_INET)) 558 goto err_free_skb; 559 560 key = &tun_info->key; 561 if (!test_bit(IP_TUNNEL_ERSPAN_OPT_BIT, tun_info->key.tun_flags)) 562 goto err_free_skb; 563 if (tun_info->options_len < sizeof(*md)) 564 goto err_free_skb; 565 md = ip_tunnel_info_opts(tun_info); 566 567 /* ERSPAN has fixed 8 byte GRE header */ 568 version = md->version; 569 tunnel_hlen = 8 + erspan_hdr_len(version); 570 571 if (skb_cow_head(skb, dev->needed_headroom)) 572 goto err_free_skb; 573 574 if (gre_handle_offloads(skb, false)) 575 goto err_free_skb; 576 577 if (skb->len > dev->mtu + dev->hard_header_len) { 578 if (pskb_trim(skb, dev->mtu + dev->hard_header_len)) 579 goto err_free_skb; 580 truncate = true; 581 } 582 583 nhoff = skb_network_offset(skb); 584 if (skb->protocol == htons(ETH_P_IP) && 585 (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff)) 586 truncate = true; 587 588 if (skb->protocol == htons(ETH_P_IPV6)) { 589 int thoff; 590 591 if (skb_transport_header_was_set(skb)) 592 thoff = skb_transport_offset(skb); 593 else 594 thoff = nhoff + sizeof(struct ipv6hdr); 595 if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff) 596 truncate = true; 597 } 598 599 if (version == 1) { 600 erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)), 601 ntohl(md->u.index), truncate, true); 602 proto = htons(ETH_P_ERSPAN); 603 } else if (version == 2) { 604 erspan_build_header_v2(skb, 605 ntohl(tunnel_id_to_key32(key->tun_id)), 606 md->u.md2.dir, 607 get_hwid(&md->u.md2), 608 truncate, true); 609 proto = htons(ETH_P_ERSPAN2); 610 } else { 611 goto err_free_skb; 612 } 613 614 __set_bit(IP_TUNNEL_SEQ_BIT, flags); 615 gre_build_header(skb, 8, flags, proto, 0, 616 htonl(atomic_fetch_inc(&tunnel->o_seqno))); 617 618 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); 619 620 return; 621 622 err_free_skb: 623 kfree_skb(skb); 624 DEV_STATS_INC(dev, tx_dropped); 625 } 626 627 static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 628 { 629 struct ip_tunnel_info *info = skb_tunnel_info(skb); 630 const struct ip_tunnel_key *key; 631 struct rtable *rt; 632 struct flowi4 fl4; 633 634 if (ip_tunnel_info_af(info) != AF_INET) 635 return -EINVAL; 636 637 key = &info->key; 638 ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src, 639 tunnel_id_to_key32(key->tun_id), 640 key->tos & ~INET_ECN_MASK, dev_net(dev), 0, 641 skb->mark, skb_get_hash(skb), key->flow_flags); 642 rt = ip_route_output_key(dev_net(dev), &fl4); 643 if (IS_ERR(rt)) 644 return PTR_ERR(rt); 645 646 ip_rt_put(rt); 647 info->key.u.ipv4.src = fl4.saddr; 648 return 0; 649 } 650 651 static netdev_tx_t ipgre_xmit(struct sk_buff *skb, 652 struct net_device *dev) 653 { 654 struct ip_tunnel *tunnel = netdev_priv(dev); 655 const struct iphdr *tnl_params; 656 657 if (!pskb_inet_may_pull(skb)) 658 goto free_skb; 659 660 if (tunnel->collect_md) { 661 gre_fb_xmit(skb, dev, skb->protocol); 662 return NETDEV_TX_OK; 663 } 664 665 if (dev->header_ops) { 666 int pull_len = tunnel->hlen + sizeof(struct iphdr); 667 668 if (skb_cow_head(skb, 0)) 669 goto free_skb; 670 671 if (!pskb_may_pull(skb, pull_len)) 672 goto free_skb; 673 674 tnl_params = (const struct iphdr *)skb->data; 675 676 /* ip_tunnel_xmit() needs skb->data pointing to gre header. */ 677 skb_pull(skb, pull_len); 678 skb_reset_mac_header(skb); 679 680 if (skb->ip_summed == CHECKSUM_PARTIAL && 681 skb_checksum_start(skb) < skb->data) 682 goto free_skb; 683 } else { 684 if (skb_cow_head(skb, dev->needed_headroom)) 685 goto free_skb; 686 687 tnl_params = &tunnel->parms.iph; 688 } 689 690 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 691 tunnel->parms.o_flags))) 692 goto free_skb; 693 694 __gre_xmit(skb, dev, tnl_params, skb->protocol); 695 return NETDEV_TX_OK; 696 697 free_skb: 698 kfree_skb(skb); 699 DEV_STATS_INC(dev, tx_dropped); 700 return NETDEV_TX_OK; 701 } 702 703 static netdev_tx_t erspan_xmit(struct sk_buff *skb, 704 struct net_device *dev) 705 { 706 struct ip_tunnel *tunnel = netdev_priv(dev); 707 bool truncate = false; 708 __be16 proto; 709 710 if (!pskb_inet_may_pull(skb)) 711 goto free_skb; 712 713 if (tunnel->collect_md) { 714 erspan_fb_xmit(skb, dev); 715 return NETDEV_TX_OK; 716 } 717 718 if (gre_handle_offloads(skb, false)) 719 goto free_skb; 720 721 if (skb_cow_head(skb, dev->needed_headroom)) 722 goto free_skb; 723 724 if (skb->len > dev->mtu + dev->hard_header_len) { 725 if (pskb_trim(skb, dev->mtu + dev->hard_header_len)) 726 goto free_skb; 727 truncate = true; 728 } 729 730 /* Push ERSPAN header */ 731 if (tunnel->erspan_ver == 0) { 732 proto = htons(ETH_P_ERSPAN); 733 __clear_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags); 734 } else if (tunnel->erspan_ver == 1) { 735 erspan_build_header(skb, ntohl(tunnel->parms.o_key), 736 tunnel->index, 737 truncate, true); 738 proto = htons(ETH_P_ERSPAN); 739 } else if (tunnel->erspan_ver == 2) { 740 erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key), 741 tunnel->dir, tunnel->hwid, 742 truncate, true); 743 proto = htons(ETH_P_ERSPAN2); 744 } else { 745 goto free_skb; 746 } 747 748 __clear_bit(IP_TUNNEL_KEY_BIT, tunnel->parms.o_flags); 749 __gre_xmit(skb, dev, &tunnel->parms.iph, proto); 750 return NETDEV_TX_OK; 751 752 free_skb: 753 kfree_skb(skb); 754 DEV_STATS_INC(dev, tx_dropped); 755 return NETDEV_TX_OK; 756 } 757 758 static netdev_tx_t gre_tap_xmit(struct sk_buff *skb, 759 struct net_device *dev) 760 { 761 struct ip_tunnel *tunnel = netdev_priv(dev); 762 763 if (!pskb_inet_may_pull(skb)) 764 goto free_skb; 765 766 if (tunnel->collect_md) { 767 gre_fb_xmit(skb, dev, htons(ETH_P_TEB)); 768 return NETDEV_TX_OK; 769 } 770 771 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 772 tunnel->parms.o_flags))) 773 goto free_skb; 774 775 if (skb_cow_head(skb, dev->needed_headroom)) 776 goto free_skb; 777 778 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB)); 779 return NETDEV_TX_OK; 780 781 free_skb: 782 kfree_skb(skb); 783 DEV_STATS_INC(dev, tx_dropped); 784 return NETDEV_TX_OK; 785 } 786 787 static void ipgre_link_update(struct net_device *dev, bool set_mtu) 788 { 789 struct ip_tunnel *tunnel = netdev_priv(dev); 790 int len; 791 792 len = tunnel->tun_hlen; 793 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 794 len = tunnel->tun_hlen - len; 795 tunnel->hlen = tunnel->hlen + len; 796 797 if (dev->header_ops) 798 dev->hard_header_len += len; 799 else 800 dev->needed_headroom += len; 801 802 if (set_mtu) 803 WRITE_ONCE(dev->mtu, max_t(int, dev->mtu - len, 68)); 804 805 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags) || 806 (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) && 807 tunnel->encap.type != TUNNEL_ENCAP_NONE)) { 808 dev->features &= ~NETIF_F_GSO_SOFTWARE; 809 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE; 810 } else { 811 dev->features |= NETIF_F_GSO_SOFTWARE; 812 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 813 } 814 } 815 816 static int ipgre_tunnel_ctl(struct net_device *dev, 817 struct ip_tunnel_parm_kern *p, 818 int cmd) 819 { 820 __be16 i_flags, o_flags; 821 int err; 822 823 if (!ip_tunnel_flags_is_be16_compat(p->i_flags) || 824 !ip_tunnel_flags_is_be16_compat(p->o_flags)) 825 return -EOVERFLOW; 826 827 i_flags = ip_tunnel_flags_to_be16(p->i_flags); 828 o_flags = ip_tunnel_flags_to_be16(p->o_flags); 829 830 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { 831 if (p->iph.version != 4 || p->iph.protocol != IPPROTO_GRE || 832 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)) || 833 ((i_flags | o_flags) & (GRE_VERSION | GRE_ROUTING))) 834 return -EINVAL; 835 } 836 837 gre_flags_to_tnl_flags(p->i_flags, i_flags); 838 gre_flags_to_tnl_flags(p->o_flags, o_flags); 839 840 err = ip_tunnel_ctl(dev, p, cmd); 841 if (err) 842 return err; 843 844 if (cmd == SIOCCHGTUNNEL) { 845 struct ip_tunnel *t = netdev_priv(dev); 846 847 ip_tunnel_flags_copy(t->parms.i_flags, p->i_flags); 848 ip_tunnel_flags_copy(t->parms.o_flags, p->o_flags); 849 850 if (strcmp(dev->rtnl_link_ops->kind, "erspan")) 851 ipgre_link_update(dev, true); 852 } 853 854 i_flags = gre_tnl_flags_to_gre_flags(p->i_flags); 855 ip_tunnel_flags_from_be16(p->i_flags, i_flags); 856 o_flags = gre_tnl_flags_to_gre_flags(p->o_flags); 857 ip_tunnel_flags_from_be16(p->o_flags, o_flags); 858 859 return 0; 860 } 861 862 /* Nice toy. Unfortunately, useless in real life :-) 863 It allows to construct virtual multiprotocol broadcast "LAN" 864 over the Internet, provided multicast routing is tuned. 865 866 867 I have no idea was this bicycle invented before me, 868 so that I had to set ARPHRD_IPGRE to a random value. 869 I have an impression, that Cisco could make something similar, 870 but this feature is apparently missing in IOS<=11.2(8). 871 872 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks 873 with broadcast 224.66.66.66. If you have access to mbone, play with me :-) 874 875 ping -t 255 224.66.66.66 876 877 If nobody answers, mbone does not work. 878 879 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255 880 ip addr add 10.66.66.<somewhat>/24 dev Universe 881 ifconfig Universe up 882 ifconfig Universe add fe80::<Your_real_addr>/10 883 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96 884 ftp 10.66.66.66 885 ... 886 ftp fec0:6666:6666::193.233.7.65 887 ... 888 */ 889 static int ipgre_header(struct sk_buff *skb, struct net_device *dev, 890 unsigned short type, 891 const void *daddr, const void *saddr, unsigned int len) 892 { 893 struct ip_tunnel *t = netdev_priv(dev); 894 struct iphdr *iph; 895 struct gre_base_hdr *greh; 896 897 iph = skb_push(skb, t->hlen + sizeof(*iph)); 898 greh = (struct gre_base_hdr *)(iph+1); 899 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags); 900 greh->protocol = htons(type); 901 902 memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); 903 904 /* Set the source hardware address. */ 905 if (saddr) 906 memcpy(&iph->saddr, saddr, 4); 907 if (daddr) 908 memcpy(&iph->daddr, daddr, 4); 909 if (iph->daddr) 910 return t->hlen + sizeof(*iph); 911 912 return -(t->hlen + sizeof(*iph)); 913 } 914 915 static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) 916 { 917 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); 918 memcpy(haddr, &iph->saddr, 4); 919 return 4; 920 } 921 922 static const struct header_ops ipgre_header_ops = { 923 .create = ipgre_header, 924 .parse = ipgre_header_parse, 925 }; 926 927 #ifdef CONFIG_NET_IPGRE_BROADCAST 928 static int ipgre_open(struct net_device *dev) 929 { 930 struct ip_tunnel *t = netdev_priv(dev); 931 932 if (ipv4_is_multicast(t->parms.iph.daddr)) { 933 struct flowi4 fl4 = { 934 .flowi4_oif = t->parms.link, 935 .flowi4_dscp = ip4h_dscp(&t->parms.iph), 936 .flowi4_scope = RT_SCOPE_UNIVERSE, 937 .flowi4_proto = IPPROTO_GRE, 938 .saddr = t->parms.iph.saddr, 939 .daddr = t->parms.iph.daddr, 940 .fl4_gre_key = t->parms.o_key, 941 }; 942 struct rtable *rt; 943 944 rt = ip_route_output_key(t->net, &fl4); 945 if (IS_ERR(rt)) 946 return -EADDRNOTAVAIL; 947 dev = rt->dst.dev; 948 ip_rt_put(rt); 949 if (!__in_dev_get_rtnl(dev)) 950 return -EADDRNOTAVAIL; 951 t->mlink = dev->ifindex; 952 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); 953 } 954 return 0; 955 } 956 957 static int ipgre_close(struct net_device *dev) 958 { 959 struct ip_tunnel *t = netdev_priv(dev); 960 961 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { 962 struct in_device *in_dev; 963 in_dev = inetdev_by_index(t->net, t->mlink); 964 if (in_dev) 965 ip_mc_dec_group(in_dev, t->parms.iph.daddr); 966 } 967 return 0; 968 } 969 #endif 970 971 static const struct net_device_ops ipgre_netdev_ops = { 972 .ndo_init = ipgre_tunnel_init, 973 .ndo_uninit = ip_tunnel_uninit, 974 #ifdef CONFIG_NET_IPGRE_BROADCAST 975 .ndo_open = ipgre_open, 976 .ndo_stop = ipgre_close, 977 #endif 978 .ndo_start_xmit = ipgre_xmit, 979 .ndo_siocdevprivate = ip_tunnel_siocdevprivate, 980 .ndo_change_mtu = ip_tunnel_change_mtu, 981 .ndo_get_stats64 = dev_get_tstats64, 982 .ndo_get_iflink = ip_tunnel_get_iflink, 983 .ndo_tunnel_ctl = ipgre_tunnel_ctl, 984 }; 985 986 #define GRE_FEATURES (NETIF_F_SG | \ 987 NETIF_F_FRAGLIST | \ 988 NETIF_F_HIGHDMA | \ 989 NETIF_F_HW_CSUM) 990 991 static void ipgre_tunnel_setup(struct net_device *dev) 992 { 993 dev->netdev_ops = &ipgre_netdev_ops; 994 dev->type = ARPHRD_IPGRE; 995 ip_tunnel_setup(dev, ipgre_net_id); 996 } 997 998 static void __gre_tunnel_init(struct net_device *dev) 999 { 1000 struct ip_tunnel *tunnel; 1001 1002 tunnel = netdev_priv(dev); 1003 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 1004 tunnel->parms.iph.protocol = IPPROTO_GRE; 1005 1006 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 1007 dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph); 1008 1009 dev->features |= GRE_FEATURES; 1010 dev->hw_features |= GRE_FEATURES; 1011 1012 /* TCP offload with GRE SEQ is not supported, nor can we support 2 1013 * levels of outer headers requiring an update. 1014 */ 1015 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags)) 1016 return; 1017 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) && 1018 tunnel->encap.type != TUNNEL_ENCAP_NONE) 1019 return; 1020 1021 dev->features |= NETIF_F_GSO_SOFTWARE; 1022 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 1023 1024 dev->lltx = true; 1025 } 1026 1027 static int ipgre_tunnel_init(struct net_device *dev) 1028 { 1029 struct ip_tunnel *tunnel = netdev_priv(dev); 1030 struct iphdr *iph = &tunnel->parms.iph; 1031 1032 __gre_tunnel_init(dev); 1033 1034 __dev_addr_set(dev, &iph->saddr, 4); 1035 memcpy(dev->broadcast, &iph->daddr, 4); 1036 1037 dev->flags = IFF_NOARP; 1038 netif_keep_dst(dev); 1039 dev->addr_len = 4; 1040 1041 if (iph->daddr && !tunnel->collect_md) { 1042 #ifdef CONFIG_NET_IPGRE_BROADCAST 1043 if (ipv4_is_multicast(iph->daddr)) { 1044 if (!iph->saddr) 1045 return -EINVAL; 1046 dev->flags = IFF_BROADCAST; 1047 dev->header_ops = &ipgre_header_ops; 1048 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1049 dev->needed_headroom = 0; 1050 } 1051 #endif 1052 } else if (!tunnel->collect_md) { 1053 dev->header_ops = &ipgre_header_ops; 1054 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1055 dev->needed_headroom = 0; 1056 } 1057 1058 return ip_tunnel_init(dev); 1059 } 1060 1061 static const struct gre_protocol ipgre_protocol = { 1062 .handler = gre_rcv, 1063 .err_handler = gre_err, 1064 }; 1065 1066 static int __net_init ipgre_init_net(struct net *net) 1067 { 1068 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); 1069 } 1070 1071 static void __net_exit ipgre_exit_rtnl(struct net *net, 1072 struct list_head *dev_to_kill) 1073 { 1074 ip_tunnel_delete_net(net, ipgre_net_id, &ipgre_link_ops, dev_to_kill); 1075 } 1076 1077 static struct pernet_operations ipgre_net_ops = { 1078 .init = ipgre_init_net, 1079 .exit_rtnl = ipgre_exit_rtnl, 1080 .id = &ipgre_net_id, 1081 .size = sizeof(struct ip_tunnel_net), 1082 }; 1083 1084 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1085 struct netlink_ext_ack *extack) 1086 { 1087 __be16 flags; 1088 1089 if (!data) 1090 return 0; 1091 1092 flags = 0; 1093 if (data[IFLA_GRE_IFLAGS]) 1094 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1095 if (data[IFLA_GRE_OFLAGS]) 1096 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1097 if (flags & (GRE_VERSION|GRE_ROUTING)) 1098 return -EINVAL; 1099 1100 if (data[IFLA_GRE_COLLECT_METADATA] && 1101 data[IFLA_GRE_ENCAP_TYPE] && 1102 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) 1103 return -EINVAL; 1104 1105 return 0; 1106 } 1107 1108 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1109 struct netlink_ext_ack *extack) 1110 { 1111 __be32 daddr; 1112 1113 if (tb[IFLA_ADDRESS]) { 1114 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1115 return -EINVAL; 1116 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1117 return -EADDRNOTAVAIL; 1118 } 1119 1120 if (!data) 1121 goto out; 1122 1123 if (data[IFLA_GRE_REMOTE]) { 1124 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); 1125 if (!daddr) 1126 return -EINVAL; 1127 } 1128 1129 out: 1130 return ipgre_tunnel_validate(tb, data, extack); 1131 } 1132 1133 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], 1134 struct netlink_ext_ack *extack) 1135 { 1136 __be16 flags = 0; 1137 int ret; 1138 1139 if (!data) 1140 return 0; 1141 1142 ret = ipgre_tap_validate(tb, data, extack); 1143 if (ret) 1144 return ret; 1145 1146 if (data[IFLA_GRE_ERSPAN_VER] && 1147 nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) 1148 return 0; 1149 1150 /* ERSPAN type II/III should only have GRE sequence and key flag */ 1151 if (data[IFLA_GRE_OFLAGS]) 1152 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1153 if (data[IFLA_GRE_IFLAGS]) 1154 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1155 if (!data[IFLA_GRE_COLLECT_METADATA] && 1156 flags != (GRE_SEQ | GRE_KEY)) 1157 return -EINVAL; 1158 1159 /* ERSPAN Session ID only has 10-bit. Since we reuse 1160 * 32-bit key field as ID, check it's range. 1161 */ 1162 if (data[IFLA_GRE_IKEY] && 1163 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK)) 1164 return -EINVAL; 1165 1166 if (data[IFLA_GRE_OKEY] && 1167 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK)) 1168 return -EINVAL; 1169 1170 return 0; 1171 } 1172 1173 static int ipgre_netlink_parms(struct net_device *dev, 1174 struct nlattr *data[], 1175 struct nlattr *tb[], 1176 struct ip_tunnel_parm_kern *parms, 1177 __u32 *fwmark) 1178 { 1179 struct ip_tunnel *t = netdev_priv(dev); 1180 1181 memset(parms, 0, sizeof(*parms)); 1182 1183 parms->iph.protocol = IPPROTO_GRE; 1184 1185 if (!data) 1186 return 0; 1187 1188 if (data[IFLA_GRE_LINK]) 1189 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1190 1191 if (data[IFLA_GRE_IFLAGS]) 1192 gre_flags_to_tnl_flags(parms->i_flags, 1193 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1194 1195 if (data[IFLA_GRE_OFLAGS]) 1196 gre_flags_to_tnl_flags(parms->o_flags, 1197 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1198 1199 if (data[IFLA_GRE_IKEY]) 1200 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1201 1202 if (data[IFLA_GRE_OKEY]) 1203 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1204 1205 if (data[IFLA_GRE_LOCAL]) 1206 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); 1207 1208 if (data[IFLA_GRE_REMOTE]) 1209 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); 1210 1211 if (data[IFLA_GRE_TTL]) 1212 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); 1213 1214 if (data[IFLA_GRE_TOS]) 1215 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); 1216 1217 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) { 1218 if (t->ignore_df) 1219 return -EINVAL; 1220 parms->iph.frag_off = htons(IP_DF); 1221 } 1222 1223 if (data[IFLA_GRE_COLLECT_METADATA]) { 1224 t->collect_md = true; 1225 if (dev->type == ARPHRD_IPGRE) 1226 dev->type = ARPHRD_NONE; 1227 } 1228 1229 if (data[IFLA_GRE_IGNORE_DF]) { 1230 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF]) 1231 && (parms->iph.frag_off & htons(IP_DF))) 1232 return -EINVAL; 1233 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]); 1234 } 1235 1236 if (data[IFLA_GRE_FWMARK]) 1237 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1238 1239 return 0; 1240 } 1241 1242 static int erspan_netlink_parms(struct net_device *dev, 1243 struct nlattr *data[], 1244 struct nlattr *tb[], 1245 struct ip_tunnel_parm_kern *parms, 1246 __u32 *fwmark) 1247 { 1248 struct ip_tunnel *t = netdev_priv(dev); 1249 int err; 1250 1251 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark); 1252 if (err) 1253 return err; 1254 if (!data) 1255 return 0; 1256 1257 if (data[IFLA_GRE_ERSPAN_VER]) { 1258 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); 1259 1260 if (t->erspan_ver > 2) 1261 return -EINVAL; 1262 } 1263 1264 if (t->erspan_ver == 1) { 1265 if (data[IFLA_GRE_ERSPAN_INDEX]) { 1266 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]); 1267 if (t->index & ~INDEX_MASK) 1268 return -EINVAL; 1269 } 1270 } else if (t->erspan_ver == 2) { 1271 if (data[IFLA_GRE_ERSPAN_DIR]) { 1272 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]); 1273 if (t->dir & ~(DIR_MASK >> DIR_OFFSET)) 1274 return -EINVAL; 1275 } 1276 if (data[IFLA_GRE_ERSPAN_HWID]) { 1277 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]); 1278 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET)) 1279 return -EINVAL; 1280 } 1281 } 1282 1283 return 0; 1284 } 1285 1286 /* This function returns true when ENCAP attributes are present in the nl msg */ 1287 static bool ipgre_netlink_encap_parms(struct nlattr *data[], 1288 struct ip_tunnel_encap *ipencap) 1289 { 1290 bool ret = false; 1291 1292 memset(ipencap, 0, sizeof(*ipencap)); 1293 1294 if (!data) 1295 return ret; 1296 1297 if (data[IFLA_GRE_ENCAP_TYPE]) { 1298 ret = true; 1299 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1300 } 1301 1302 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1303 ret = true; 1304 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1305 } 1306 1307 if (data[IFLA_GRE_ENCAP_SPORT]) { 1308 ret = true; 1309 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1310 } 1311 1312 if (data[IFLA_GRE_ENCAP_DPORT]) { 1313 ret = true; 1314 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1315 } 1316 1317 return ret; 1318 } 1319 1320 static int gre_tap_init(struct net_device *dev) 1321 { 1322 __gre_tunnel_init(dev); 1323 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1324 netif_keep_dst(dev); 1325 1326 return ip_tunnel_init(dev); 1327 } 1328 1329 static const struct net_device_ops gre_tap_netdev_ops = { 1330 .ndo_init = gre_tap_init, 1331 .ndo_uninit = ip_tunnel_uninit, 1332 .ndo_start_xmit = gre_tap_xmit, 1333 .ndo_set_mac_address = eth_mac_addr, 1334 .ndo_validate_addr = eth_validate_addr, 1335 .ndo_change_mtu = ip_tunnel_change_mtu, 1336 .ndo_get_stats64 = dev_get_tstats64, 1337 .ndo_get_iflink = ip_tunnel_get_iflink, 1338 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1339 }; 1340 1341 static int erspan_tunnel_init(struct net_device *dev) 1342 { 1343 struct ip_tunnel *tunnel = netdev_priv(dev); 1344 1345 if (tunnel->erspan_ver == 0) 1346 tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ 1347 else 1348 tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ 1349 1350 tunnel->parms.iph.protocol = IPPROTO_GRE; 1351 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + 1352 erspan_hdr_len(tunnel->erspan_ver); 1353 1354 dev->features |= GRE_FEATURES; 1355 dev->hw_features |= GRE_FEATURES; 1356 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1357 netif_keep_dst(dev); 1358 1359 return ip_tunnel_init(dev); 1360 } 1361 1362 static const struct net_device_ops erspan_netdev_ops = { 1363 .ndo_init = erspan_tunnel_init, 1364 .ndo_uninit = ip_tunnel_uninit, 1365 .ndo_start_xmit = erspan_xmit, 1366 .ndo_set_mac_address = eth_mac_addr, 1367 .ndo_validate_addr = eth_validate_addr, 1368 .ndo_change_mtu = ip_tunnel_change_mtu, 1369 .ndo_get_stats64 = dev_get_tstats64, 1370 .ndo_get_iflink = ip_tunnel_get_iflink, 1371 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1372 }; 1373 1374 static void ipgre_tap_setup(struct net_device *dev) 1375 { 1376 ether_setup(dev); 1377 dev->max_mtu = 0; 1378 dev->netdev_ops = &gre_tap_netdev_ops; 1379 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1380 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1381 ip_tunnel_setup(dev, gre_tap_net_id); 1382 } 1383 1384 static int 1385 ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[]) 1386 { 1387 struct ip_tunnel_encap ipencap; 1388 1389 if (ipgre_netlink_encap_parms(data, &ipencap)) { 1390 struct ip_tunnel *t = netdev_priv(dev); 1391 int err = ip_tunnel_encap_setup(t, &ipencap); 1392 1393 if (err < 0) 1394 return err; 1395 } 1396 1397 return 0; 1398 } 1399 1400 static int ipgre_newlink(struct net_device *dev, 1401 struct rtnl_newlink_params *params, 1402 struct netlink_ext_ack *extack) 1403 { 1404 struct nlattr **data = params->data; 1405 struct nlattr **tb = params->tb; 1406 struct ip_tunnel_parm_kern p; 1407 __u32 fwmark = 0; 1408 int err; 1409 1410 err = ipgre_newlink_encap_setup(dev, data); 1411 if (err) 1412 return err; 1413 1414 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1415 if (err < 0) 1416 return err; 1417 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1418 fwmark); 1419 } 1420 1421 static int erspan_newlink(struct net_device *dev, 1422 struct rtnl_newlink_params *params, 1423 struct netlink_ext_ack *extack) 1424 { 1425 struct nlattr **data = params->data; 1426 struct nlattr **tb = params->tb; 1427 struct ip_tunnel_parm_kern p; 1428 __u32 fwmark = 0; 1429 int err; 1430 1431 err = ipgre_newlink_encap_setup(dev, data); 1432 if (err) 1433 return err; 1434 1435 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1436 if (err) 1437 return err; 1438 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1439 fwmark); 1440 } 1441 1442 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], 1443 struct nlattr *data[], 1444 struct netlink_ext_ack *extack) 1445 { 1446 struct ip_tunnel *t = netdev_priv(dev); 1447 struct ip_tunnel_parm_kern p; 1448 __u32 fwmark = t->fwmark; 1449 int err; 1450 1451 err = ipgre_newlink_encap_setup(dev, data); 1452 if (err) 1453 return err; 1454 1455 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1456 if (err < 0) 1457 return err; 1458 1459 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1460 if (err < 0) 1461 return err; 1462 1463 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1464 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1465 1466 ipgre_link_update(dev, !tb[IFLA_MTU]); 1467 1468 return 0; 1469 } 1470 1471 static int erspan_changelink(struct net_device *dev, struct nlattr *tb[], 1472 struct nlattr *data[], 1473 struct netlink_ext_ack *extack) 1474 { 1475 struct ip_tunnel *t = netdev_priv(dev); 1476 struct ip_tunnel_parm_kern p; 1477 __u32 fwmark = t->fwmark; 1478 int err; 1479 1480 err = ipgre_newlink_encap_setup(dev, data); 1481 if (err) 1482 return err; 1483 1484 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1485 if (err < 0) 1486 return err; 1487 1488 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1489 if (err < 0) 1490 return err; 1491 1492 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1493 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1494 1495 return 0; 1496 } 1497 1498 static size_t ipgre_get_size(const struct net_device *dev) 1499 { 1500 return 1501 /* IFLA_GRE_LINK */ 1502 nla_total_size(4) + 1503 /* IFLA_GRE_IFLAGS */ 1504 nla_total_size(2) + 1505 /* IFLA_GRE_OFLAGS */ 1506 nla_total_size(2) + 1507 /* IFLA_GRE_IKEY */ 1508 nla_total_size(4) + 1509 /* IFLA_GRE_OKEY */ 1510 nla_total_size(4) + 1511 /* IFLA_GRE_LOCAL */ 1512 nla_total_size(4) + 1513 /* IFLA_GRE_REMOTE */ 1514 nla_total_size(4) + 1515 /* IFLA_GRE_TTL */ 1516 nla_total_size(1) + 1517 /* IFLA_GRE_TOS */ 1518 nla_total_size(1) + 1519 /* IFLA_GRE_PMTUDISC */ 1520 nla_total_size(1) + 1521 /* IFLA_GRE_ENCAP_TYPE */ 1522 nla_total_size(2) + 1523 /* IFLA_GRE_ENCAP_FLAGS */ 1524 nla_total_size(2) + 1525 /* IFLA_GRE_ENCAP_SPORT */ 1526 nla_total_size(2) + 1527 /* IFLA_GRE_ENCAP_DPORT */ 1528 nla_total_size(2) + 1529 /* IFLA_GRE_COLLECT_METADATA */ 1530 nla_total_size(0) + 1531 /* IFLA_GRE_IGNORE_DF */ 1532 nla_total_size(1) + 1533 /* IFLA_GRE_FWMARK */ 1534 nla_total_size(4) + 1535 /* IFLA_GRE_ERSPAN_INDEX */ 1536 nla_total_size(4) + 1537 /* IFLA_GRE_ERSPAN_VER */ 1538 nla_total_size(1) + 1539 /* IFLA_GRE_ERSPAN_DIR */ 1540 nla_total_size(1) + 1541 /* IFLA_GRE_ERSPAN_HWID */ 1542 nla_total_size(2) + 1543 0; 1544 } 1545 1546 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1547 { 1548 struct ip_tunnel *t = netdev_priv(dev); 1549 struct ip_tunnel_parm_kern *p = &t->parms; 1550 IP_TUNNEL_DECLARE_FLAGS(o_flags); 1551 1552 ip_tunnel_flags_copy(o_flags, p->o_flags); 1553 1554 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1555 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1556 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1557 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1558 gre_tnl_flags_to_gre_flags(o_flags)) || 1559 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1560 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1561 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || 1562 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || 1563 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || 1564 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || 1565 nla_put_u8(skb, IFLA_GRE_PMTUDISC, 1566 !!(p->iph.frag_off & htons(IP_DF))) || 1567 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark)) 1568 goto nla_put_failure; 1569 1570 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1571 t->encap.type) || 1572 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1573 t->encap.sport) || 1574 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1575 t->encap.dport) || 1576 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1577 t->encap.flags)) 1578 goto nla_put_failure; 1579 1580 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df)) 1581 goto nla_put_failure; 1582 1583 if (t->collect_md) { 1584 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) 1585 goto nla_put_failure; 1586 } 1587 1588 return 0; 1589 1590 nla_put_failure: 1591 return -EMSGSIZE; 1592 } 1593 1594 static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev) 1595 { 1596 struct ip_tunnel *t = netdev_priv(dev); 1597 1598 if (t->erspan_ver <= 2) { 1599 if (t->erspan_ver != 0 && !t->collect_md) 1600 __set_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags); 1601 1602 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) 1603 goto nla_put_failure; 1604 1605 if (t->erspan_ver == 1) { 1606 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) 1607 goto nla_put_failure; 1608 } else if (t->erspan_ver == 2) { 1609 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) 1610 goto nla_put_failure; 1611 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid)) 1612 goto nla_put_failure; 1613 } 1614 } 1615 1616 return ipgre_fill_info(skb, dev); 1617 1618 nla_put_failure: 1619 return -EMSGSIZE; 1620 } 1621 1622 static void erspan_setup(struct net_device *dev) 1623 { 1624 struct ip_tunnel *t = netdev_priv(dev); 1625 1626 ether_setup(dev); 1627 dev->max_mtu = 0; 1628 dev->netdev_ops = &erspan_netdev_ops; 1629 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1630 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1631 ip_tunnel_setup(dev, erspan_net_id); 1632 t->erspan_ver = 1; 1633 } 1634 1635 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { 1636 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1637 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1638 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1639 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1640 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1641 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) }, 1642 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, 1643 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1644 [IFLA_GRE_TOS] = { .type = NLA_U8 }, 1645 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, 1646 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1647 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1648 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1649 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1650 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, 1651 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 }, 1652 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1653 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 }, 1654 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 }, 1655 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 }, 1656 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 }, 1657 }; 1658 1659 static struct rtnl_link_ops ipgre_link_ops __read_mostly = { 1660 .kind = "gre", 1661 .maxtype = IFLA_GRE_MAX, 1662 .policy = ipgre_policy, 1663 .priv_size = sizeof(struct ip_tunnel), 1664 .setup = ipgre_tunnel_setup, 1665 .validate = ipgre_tunnel_validate, 1666 .newlink = ipgre_newlink, 1667 .changelink = ipgre_changelink, 1668 .dellink = ip_tunnel_dellink, 1669 .get_size = ipgre_get_size, 1670 .fill_info = ipgre_fill_info, 1671 .get_link_net = ip_tunnel_get_link_net, 1672 }; 1673 1674 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { 1675 .kind = "gretap", 1676 .maxtype = IFLA_GRE_MAX, 1677 .policy = ipgre_policy, 1678 .priv_size = sizeof(struct ip_tunnel), 1679 .setup = ipgre_tap_setup, 1680 .validate = ipgre_tap_validate, 1681 .newlink = ipgre_newlink, 1682 .changelink = ipgre_changelink, 1683 .dellink = ip_tunnel_dellink, 1684 .get_size = ipgre_get_size, 1685 .fill_info = ipgre_fill_info, 1686 .get_link_net = ip_tunnel_get_link_net, 1687 }; 1688 1689 static struct rtnl_link_ops erspan_link_ops __read_mostly = { 1690 .kind = "erspan", 1691 .maxtype = IFLA_GRE_MAX, 1692 .policy = ipgre_policy, 1693 .priv_size = sizeof(struct ip_tunnel), 1694 .setup = erspan_setup, 1695 .validate = erspan_validate, 1696 .newlink = erspan_newlink, 1697 .changelink = erspan_changelink, 1698 .dellink = ip_tunnel_dellink, 1699 .get_size = ipgre_get_size, 1700 .fill_info = erspan_fill_info, 1701 .get_link_net = ip_tunnel_get_link_net, 1702 }; 1703 1704 struct net_device *gretap_fb_dev_create(struct net *net, const char *name, 1705 u8 name_assign_type) 1706 { 1707 struct rtnl_newlink_params params = { .src_net = net }; 1708 struct nlattr *tb[IFLA_MAX + 1]; 1709 struct net_device *dev; 1710 LIST_HEAD(list_kill); 1711 struct ip_tunnel *t; 1712 int err; 1713 1714 memset(&tb, 0, sizeof(tb)); 1715 params.tb = tb; 1716 1717 dev = rtnl_create_link(net, name, name_assign_type, 1718 &ipgre_tap_ops, tb, NULL); 1719 if (IS_ERR(dev)) 1720 return dev; 1721 1722 /* Configure flow based GRE device. */ 1723 t = netdev_priv(dev); 1724 t->collect_md = true; 1725 1726 err = ipgre_newlink(dev, ¶ms, NULL); 1727 if (err < 0) { 1728 free_netdev(dev); 1729 return ERR_PTR(err); 1730 } 1731 1732 /* openvswitch users expect packet sizes to be unrestricted, 1733 * so set the largest MTU we can. 1734 */ 1735 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); 1736 if (err) 1737 goto out; 1738 1739 err = rtnl_configure_link(dev, NULL, 0, NULL); 1740 if (err < 0) 1741 goto out; 1742 1743 return dev; 1744 out: 1745 ip_tunnel_dellink(dev, &list_kill); 1746 unregister_netdevice_many(&list_kill); 1747 return ERR_PTR(err); 1748 } 1749 EXPORT_SYMBOL_GPL(gretap_fb_dev_create); 1750 1751 static int __net_init ipgre_tap_init_net(struct net *net) 1752 { 1753 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); 1754 } 1755 1756 static void __net_exit ipgre_tap_exit_rtnl(struct net *net, 1757 struct list_head *dev_to_kill) 1758 { 1759 ip_tunnel_delete_net(net, gre_tap_net_id, &ipgre_tap_ops, dev_to_kill); 1760 } 1761 1762 static struct pernet_operations ipgre_tap_net_ops = { 1763 .init = ipgre_tap_init_net, 1764 .exit_rtnl = ipgre_tap_exit_rtnl, 1765 .id = &gre_tap_net_id, 1766 .size = sizeof(struct ip_tunnel_net), 1767 }; 1768 1769 static int __net_init erspan_init_net(struct net *net) 1770 { 1771 return ip_tunnel_init_net(net, erspan_net_id, 1772 &erspan_link_ops, "erspan0"); 1773 } 1774 1775 static void __net_exit erspan_exit_rtnl(struct net *net, 1776 struct list_head *dev_to_kill) 1777 { 1778 ip_tunnel_delete_net(net, erspan_net_id, &erspan_link_ops, dev_to_kill); 1779 } 1780 1781 static struct pernet_operations erspan_net_ops = { 1782 .init = erspan_init_net, 1783 .exit_rtnl = erspan_exit_rtnl, 1784 .id = &erspan_net_id, 1785 .size = sizeof(struct ip_tunnel_net), 1786 }; 1787 1788 static int __init ipgre_init(void) 1789 { 1790 int err; 1791 1792 pr_info("GRE over IPv4 tunneling driver\n"); 1793 1794 err = register_pernet_device(&ipgre_net_ops); 1795 if (err < 0) 1796 return err; 1797 1798 err = register_pernet_device(&ipgre_tap_net_ops); 1799 if (err < 0) 1800 goto pnet_tap_failed; 1801 1802 err = register_pernet_device(&erspan_net_ops); 1803 if (err < 0) 1804 goto pnet_erspan_failed; 1805 1806 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); 1807 if (err < 0) { 1808 pr_info("%s: can't add protocol\n", __func__); 1809 goto add_proto_failed; 1810 } 1811 1812 err = rtnl_link_register(&ipgre_link_ops); 1813 if (err < 0) 1814 goto rtnl_link_failed; 1815 1816 err = rtnl_link_register(&ipgre_tap_ops); 1817 if (err < 0) 1818 goto tap_ops_failed; 1819 1820 err = rtnl_link_register(&erspan_link_ops); 1821 if (err < 0) 1822 goto erspan_link_failed; 1823 1824 return 0; 1825 1826 erspan_link_failed: 1827 rtnl_link_unregister(&ipgre_tap_ops); 1828 tap_ops_failed: 1829 rtnl_link_unregister(&ipgre_link_ops); 1830 rtnl_link_failed: 1831 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1832 add_proto_failed: 1833 unregister_pernet_device(&erspan_net_ops); 1834 pnet_erspan_failed: 1835 unregister_pernet_device(&ipgre_tap_net_ops); 1836 pnet_tap_failed: 1837 unregister_pernet_device(&ipgre_net_ops); 1838 return err; 1839 } 1840 1841 static void __exit ipgre_fini(void) 1842 { 1843 rtnl_link_unregister(&ipgre_tap_ops); 1844 rtnl_link_unregister(&ipgre_link_ops); 1845 rtnl_link_unregister(&erspan_link_ops); 1846 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1847 unregister_pernet_device(&ipgre_tap_net_ops); 1848 unregister_pernet_device(&ipgre_net_ops); 1849 unregister_pernet_device(&erspan_net_ops); 1850 } 1851 1852 module_init(ipgre_init); 1853 module_exit(ipgre_fini); 1854 MODULE_DESCRIPTION("IPv4 GRE tunnels over IP library"); 1855 MODULE_LICENSE("GPL"); 1856 MODULE_ALIAS_RTNL_LINK("gre"); 1857 MODULE_ALIAS_RTNL_LINK("gretap"); 1858 MODULE_ALIAS_RTNL_LINK("erspan"); 1859 MODULE_ALIAS_NETDEV("gre0"); 1860 MODULE_ALIAS_NETDEV("gretap0"); 1861 MODULE_ALIAS_NETDEV("erspan0"); 1862