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/sock.h> 32 #include <net/ip.h> 33 #include <net/icmp.h> 34 #include <net/protocol.h> 35 #include <net/ip_tunnels.h> 36 #include <net/arp.h> 37 #include <net/checksum.h> 38 #include <net/dsfield.h> 39 #include <net/inet_ecn.h> 40 #include <net/xfrm.h> 41 #include <net/net_namespace.h> 42 #include <net/netns/generic.h> 43 #include <net/rtnetlink.h> 44 #include <net/gre.h> 45 #include <net/dst_metadata.h> 46 #include <net/erspan.h> 47 #include <net/inet_dscp.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 /* skb can be uncloned in __iptunnel_pull_header, so 334 * old pkt_md is no longer valid and we need to reset 335 * it 336 */ 337 gh = skb_network_header(skb) + 338 skb_network_header_len(skb); 339 pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len + 340 sizeof(*ershdr)); 341 md = ip_tunnel_info_opts(&tun_dst->u.tun_info); 342 md->version = ver; 343 md2 = &md->u.md2; 344 memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE : 345 ERSPAN_V2_MDSIZE); 346 347 info = &tun_dst->u.tun_info; 348 __set_bit(IP_TUNNEL_ERSPAN_OPT_BIT, 349 info->key.tun_flags); 350 info->options_len = sizeof(*md); 351 } 352 353 skb_reset_mac_header(skb); 354 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); 355 return PACKET_RCVD; 356 } 357 return PACKET_REJECT; 358 359 drop: 360 kfree_skb(skb); 361 return PACKET_RCVD; 362 } 363 364 static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, 365 struct ip_tunnel_net *itn, int hdr_len, bool raw_proto) 366 { 367 struct metadata_dst *tun_dst = NULL; 368 const struct iphdr *iph; 369 struct ip_tunnel *tunnel; 370 371 iph = ip_hdr(skb); 372 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, 373 iph->saddr, iph->daddr, tpi->key); 374 375 if (tunnel) { 376 const struct iphdr *tnl_params; 377 378 if (__iptunnel_pull_header(skb, hdr_len, tpi->proto, 379 raw_proto, false) < 0) 380 goto drop; 381 382 /* Special case for ipgre_header_parse(), which expects the 383 * mac_header to point to the outer IP header. 384 */ 385 if (tunnel->dev->header_ops == &ipgre_header_ops) 386 skb_pop_mac_header(skb); 387 else 388 skb_reset_mac_header(skb); 389 390 tnl_params = &tunnel->parms.iph; 391 if (tunnel->collect_md || tnl_params->daddr == 0) { 392 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 393 __be64 tun_id; 394 395 __set_bit(IP_TUNNEL_CSUM_BIT, flags); 396 __set_bit(IP_TUNNEL_KEY_BIT, flags); 397 ip_tunnel_flags_and(flags, tpi->flags, flags); 398 399 tun_id = key32_to_tunnel_id(tpi->key); 400 tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0); 401 if (!tun_dst) 402 return PACKET_REJECT; 403 } 404 405 ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); 406 return PACKET_RCVD; 407 } 408 return PACKET_NEXT; 409 410 drop: 411 kfree_skb(skb); 412 return PACKET_RCVD; 413 } 414 415 static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, 416 int hdr_len) 417 { 418 struct net *net = dev_net(skb->dev); 419 struct ip_tunnel_net *itn; 420 int res; 421 422 if (tpi->proto == htons(ETH_P_TEB)) 423 itn = net_generic(net, gre_tap_net_id); 424 else 425 itn = net_generic(net, ipgre_net_id); 426 427 res = __ipgre_rcv(skb, tpi, itn, hdr_len, false); 428 if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) { 429 /* ipgre tunnels in collect metadata mode should receive 430 * also ETH_P_TEB traffic. 431 */ 432 itn = net_generic(net, ipgre_net_id); 433 res = __ipgre_rcv(skb, tpi, itn, hdr_len, true); 434 } 435 return res; 436 } 437 438 static int gre_rcv(struct sk_buff *skb) 439 { 440 struct tnl_ptk_info tpi; 441 bool csum_err = false; 442 int hdr_len; 443 444 #ifdef CONFIG_NET_IPGRE_BROADCAST 445 if (ipv4_is_multicast(ip_hdr(skb)->daddr)) { 446 /* Looped back packet, drop it! */ 447 if (rt_is_output_route(skb_rtable(skb))) 448 goto drop; 449 } 450 #endif 451 452 hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0); 453 if (hdr_len < 0) 454 goto drop; 455 456 if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) || 457 tpi.proto == htons(ETH_P_ERSPAN2))) { 458 if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) 459 return 0; 460 goto out; 461 } 462 463 if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) 464 return 0; 465 466 out: 467 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); 468 drop: 469 kfree_skb(skb); 470 return 0; 471 } 472 473 static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, 474 const struct iphdr *tnl_params, 475 __be16 proto) 476 { 477 struct ip_tunnel *tunnel = netdev_priv(dev); 478 IP_TUNNEL_DECLARE_FLAGS(flags); 479 480 ip_tunnel_flags_copy(flags, tunnel->parms.o_flags); 481 482 /* Push GRE header. */ 483 gre_build_header(skb, tunnel->tun_hlen, 484 flags, proto, tunnel->parms.o_key, 485 test_bit(IP_TUNNEL_SEQ_BIT, flags) ? 486 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); 487 488 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol); 489 } 490 491 static int gre_handle_offloads(struct sk_buff *skb, bool csum) 492 { 493 return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); 494 } 495 496 static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev, 497 __be16 proto) 498 { 499 struct ip_tunnel *tunnel = netdev_priv(dev); 500 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 501 struct ip_tunnel_info *tun_info; 502 const struct ip_tunnel_key *key; 503 int tunnel_hlen; 504 505 tun_info = skb_tunnel_info(skb); 506 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 507 ip_tunnel_info_af(tun_info) != AF_INET)) 508 goto err_free_skb; 509 510 key = &tun_info->key; 511 tunnel_hlen = gre_calc_hlen(key->tun_flags); 512 513 if (skb_cow_head(skb, dev->needed_headroom)) 514 goto err_free_skb; 515 516 /* Push Tunnel header. */ 517 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 518 tunnel->parms.o_flags))) 519 goto err_free_skb; 520 521 __set_bit(IP_TUNNEL_CSUM_BIT, flags); 522 __set_bit(IP_TUNNEL_KEY_BIT, flags); 523 __set_bit(IP_TUNNEL_SEQ_BIT, flags); 524 ip_tunnel_flags_and(flags, tun_info->key.tun_flags, flags); 525 526 gre_build_header(skb, tunnel_hlen, flags, proto, 527 tunnel_id_to_key32(tun_info->key.tun_id), 528 test_bit(IP_TUNNEL_SEQ_BIT, flags) ? 529 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); 530 531 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); 532 533 return; 534 535 err_free_skb: 536 kfree_skb(skb); 537 DEV_STATS_INC(dev, tx_dropped); 538 } 539 540 static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev) 541 { 542 struct ip_tunnel *tunnel = netdev_priv(dev); 543 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 544 struct ip_tunnel_info *tun_info; 545 const struct ip_tunnel_key *key; 546 struct erspan_metadata *md; 547 bool truncate = false; 548 __be16 proto; 549 int tunnel_hlen; 550 int version; 551 int nhoff; 552 553 tun_info = skb_tunnel_info(skb); 554 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 555 ip_tunnel_info_af(tun_info) != AF_INET)) 556 goto err_free_skb; 557 558 key = &tun_info->key; 559 if (!test_bit(IP_TUNNEL_ERSPAN_OPT_BIT, tun_info->key.tun_flags)) 560 goto err_free_skb; 561 if (tun_info->options_len < sizeof(*md)) 562 goto err_free_skb; 563 md = ip_tunnel_info_opts(tun_info); 564 565 /* ERSPAN has fixed 8 byte GRE header */ 566 version = md->version; 567 tunnel_hlen = 8 + erspan_hdr_len(version); 568 569 if (skb_cow_head(skb, dev->needed_headroom)) 570 goto err_free_skb; 571 572 if (gre_handle_offloads(skb, false)) 573 goto err_free_skb; 574 575 if (skb->len > dev->mtu + dev->hard_header_len) { 576 if (pskb_trim(skb, dev->mtu + dev->hard_header_len)) 577 goto err_free_skb; 578 truncate = true; 579 } 580 581 nhoff = skb_network_offset(skb); 582 if (skb->protocol == htons(ETH_P_IP) && 583 (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff)) 584 truncate = true; 585 586 if (skb->protocol == htons(ETH_P_IPV6)) { 587 int thoff; 588 589 if (skb_transport_header_was_set(skb)) 590 thoff = skb_transport_offset(skb); 591 else 592 thoff = nhoff + sizeof(struct ipv6hdr); 593 if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff) 594 truncate = true; 595 } 596 597 if (version == 1) { 598 erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)), 599 ntohl(md->u.index), truncate, true); 600 proto = htons(ETH_P_ERSPAN); 601 } else if (version == 2) { 602 erspan_build_header_v2(skb, 603 ntohl(tunnel_id_to_key32(key->tun_id)), 604 md->u.md2.dir, 605 get_hwid(&md->u.md2), 606 truncate, true); 607 proto = htons(ETH_P_ERSPAN2); 608 } else { 609 goto err_free_skb; 610 } 611 612 __set_bit(IP_TUNNEL_SEQ_BIT, flags); 613 gre_build_header(skb, 8, flags, proto, 0, 614 htonl(atomic_fetch_inc(&tunnel->o_seqno))); 615 616 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); 617 618 return; 619 620 err_free_skb: 621 kfree_skb(skb); 622 DEV_STATS_INC(dev, tx_dropped); 623 } 624 625 static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 626 { 627 struct ip_tunnel_info *info = skb_tunnel_info(skb); 628 const struct ip_tunnel_key *key; 629 struct rtable *rt; 630 struct flowi4 fl4; 631 632 if (ip_tunnel_info_af(info) != AF_INET) 633 return -EINVAL; 634 635 key = &info->key; 636 ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src, 637 tunnel_id_to_key32(key->tun_id), 638 key->tos & ~INET_ECN_MASK, dev_net(dev), 0, 639 skb->mark, skb_get_hash(skb), key->flow_flags); 640 rt = ip_route_output_key(dev_net(dev), &fl4); 641 if (IS_ERR(rt)) 642 return PTR_ERR(rt); 643 644 ip_rt_put(rt); 645 info->key.u.ipv4.src = fl4.saddr; 646 return 0; 647 } 648 649 static netdev_tx_t ipgre_xmit(struct sk_buff *skb, 650 struct net_device *dev) 651 { 652 struct ip_tunnel *tunnel = netdev_priv(dev); 653 const struct iphdr *tnl_params; 654 655 if (!pskb_inet_may_pull(skb)) 656 goto free_skb; 657 658 if (tunnel->collect_md) { 659 gre_fb_xmit(skb, dev, skb->protocol); 660 return NETDEV_TX_OK; 661 } 662 663 if (dev->header_ops) { 664 int pull_len = tunnel->hlen + sizeof(struct iphdr); 665 666 if (skb_cow_head(skb, 0)) 667 goto free_skb; 668 669 if (!pskb_may_pull(skb, pull_len)) 670 goto free_skb; 671 672 tnl_params = (const struct iphdr *)skb->data; 673 674 /* ip_tunnel_xmit() needs skb->data pointing to gre header. */ 675 skb_pull(skb, pull_len); 676 skb_reset_mac_header(skb); 677 678 if (skb->ip_summed == CHECKSUM_PARTIAL && 679 skb_checksum_start(skb) < skb->data) 680 goto free_skb; 681 } else { 682 if (skb_cow_head(skb, dev->needed_headroom)) 683 goto free_skb; 684 685 tnl_params = &tunnel->parms.iph; 686 } 687 688 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 689 tunnel->parms.o_flags))) 690 goto free_skb; 691 692 __gre_xmit(skb, dev, tnl_params, skb->protocol); 693 return NETDEV_TX_OK; 694 695 free_skb: 696 kfree_skb(skb); 697 DEV_STATS_INC(dev, tx_dropped); 698 return NETDEV_TX_OK; 699 } 700 701 static netdev_tx_t erspan_xmit(struct sk_buff *skb, 702 struct net_device *dev) 703 { 704 struct ip_tunnel *tunnel = netdev_priv(dev); 705 bool truncate = false; 706 __be16 proto; 707 708 if (!pskb_inet_may_pull(skb)) 709 goto free_skb; 710 711 if (tunnel->collect_md) { 712 erspan_fb_xmit(skb, dev); 713 return NETDEV_TX_OK; 714 } 715 716 if (gre_handle_offloads(skb, false)) 717 goto free_skb; 718 719 if (skb_cow_head(skb, dev->needed_headroom)) 720 goto free_skb; 721 722 if (skb->len > dev->mtu + dev->hard_header_len) { 723 if (pskb_trim(skb, dev->mtu + dev->hard_header_len)) 724 goto free_skb; 725 truncate = true; 726 } 727 728 /* Push ERSPAN header */ 729 if (tunnel->erspan_ver == 0) { 730 proto = htons(ETH_P_ERSPAN); 731 __clear_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags); 732 } else if (tunnel->erspan_ver == 1) { 733 erspan_build_header(skb, ntohl(tunnel->parms.o_key), 734 tunnel->index, 735 truncate, true); 736 proto = htons(ETH_P_ERSPAN); 737 } else if (tunnel->erspan_ver == 2) { 738 erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key), 739 tunnel->dir, tunnel->hwid, 740 truncate, true); 741 proto = htons(ETH_P_ERSPAN2); 742 } else { 743 goto free_skb; 744 } 745 746 __clear_bit(IP_TUNNEL_KEY_BIT, tunnel->parms.o_flags); 747 __gre_xmit(skb, dev, &tunnel->parms.iph, proto); 748 return NETDEV_TX_OK; 749 750 free_skb: 751 kfree_skb(skb); 752 DEV_STATS_INC(dev, tx_dropped); 753 return NETDEV_TX_OK; 754 } 755 756 static netdev_tx_t gre_tap_xmit(struct sk_buff *skb, 757 struct net_device *dev) 758 { 759 struct ip_tunnel *tunnel = netdev_priv(dev); 760 761 if (!pskb_inet_may_pull(skb)) 762 goto free_skb; 763 764 if (tunnel->collect_md) { 765 gre_fb_xmit(skb, dev, htons(ETH_P_TEB)); 766 return NETDEV_TX_OK; 767 } 768 769 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 770 tunnel->parms.o_flags))) 771 goto free_skb; 772 773 if (skb_cow_head(skb, dev->needed_headroom)) 774 goto free_skb; 775 776 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB)); 777 return NETDEV_TX_OK; 778 779 free_skb: 780 kfree_skb(skb); 781 DEV_STATS_INC(dev, tx_dropped); 782 return NETDEV_TX_OK; 783 } 784 785 static void ipgre_link_update(struct net_device *dev, bool set_mtu) 786 { 787 struct ip_tunnel *tunnel = netdev_priv(dev); 788 int len; 789 790 len = tunnel->tun_hlen; 791 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 792 len = tunnel->tun_hlen - len; 793 tunnel->hlen = tunnel->hlen + len; 794 795 if (dev->header_ops) 796 dev->hard_header_len += len; 797 else 798 dev->needed_headroom += len; 799 800 if (set_mtu) 801 WRITE_ONCE(dev->mtu, max_t(int, dev->mtu - len, 68)); 802 803 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags) || 804 (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) && 805 tunnel->encap.type != TUNNEL_ENCAP_NONE)) { 806 dev->features &= ~NETIF_F_GSO_SOFTWARE; 807 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE; 808 } else { 809 dev->features |= NETIF_F_GSO_SOFTWARE; 810 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 811 } 812 } 813 814 static int ipgre_tunnel_ctl(struct net_device *dev, 815 struct ip_tunnel_parm_kern *p, 816 int cmd) 817 { 818 __be16 i_flags, o_flags; 819 int err; 820 821 if (!ip_tunnel_flags_is_be16_compat(p->i_flags) || 822 !ip_tunnel_flags_is_be16_compat(p->o_flags)) 823 return -EOVERFLOW; 824 825 i_flags = ip_tunnel_flags_to_be16(p->i_flags); 826 o_flags = ip_tunnel_flags_to_be16(p->o_flags); 827 828 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { 829 if (p->iph.version != 4 || p->iph.protocol != IPPROTO_GRE || 830 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)) || 831 ((i_flags | o_flags) & (GRE_VERSION | GRE_ROUTING))) 832 return -EINVAL; 833 } 834 835 gre_flags_to_tnl_flags(p->i_flags, i_flags); 836 gre_flags_to_tnl_flags(p->o_flags, o_flags); 837 838 err = ip_tunnel_ctl(dev, p, cmd); 839 if (err) 840 return err; 841 842 if (cmd == SIOCCHGTUNNEL) { 843 struct ip_tunnel *t = netdev_priv(dev); 844 845 ip_tunnel_flags_copy(t->parms.i_flags, p->i_flags); 846 ip_tunnel_flags_copy(t->parms.o_flags, p->o_flags); 847 848 if (strcmp(dev->rtnl_link_ops->kind, "erspan")) 849 ipgre_link_update(dev, true); 850 } 851 852 i_flags = gre_tnl_flags_to_gre_flags(p->i_flags); 853 ip_tunnel_flags_from_be16(p->i_flags, i_flags); 854 o_flags = gre_tnl_flags_to_gre_flags(p->o_flags); 855 ip_tunnel_flags_from_be16(p->o_flags, o_flags); 856 857 return 0; 858 } 859 860 /* Nice toy. Unfortunately, useless in real life :-) 861 It allows to construct virtual multiprotocol broadcast "LAN" 862 over the Internet, provided multicast routing is tuned. 863 864 865 I have no idea was this bicycle invented before me, 866 so that I had to set ARPHRD_IPGRE to a random value. 867 I have an impression, that Cisco could make something similar, 868 but this feature is apparently missing in IOS<=11.2(8). 869 870 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks 871 with broadcast 224.66.66.66. If you have access to mbone, play with me :-) 872 873 ping -t 255 224.66.66.66 874 875 If nobody answers, mbone does not work. 876 877 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255 878 ip addr add 10.66.66.<somewhat>/24 dev Universe 879 ifconfig Universe up 880 ifconfig Universe add fe80::<Your_real_addr>/10 881 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96 882 ftp 10.66.66.66 883 ... 884 ftp fec0:6666:6666::193.233.7.65 885 ... 886 */ 887 static int ipgre_header(struct sk_buff *skb, struct net_device *dev, 888 unsigned short type, 889 const void *daddr, const void *saddr, unsigned int len) 890 { 891 struct ip_tunnel *t = netdev_priv(dev); 892 struct iphdr *iph; 893 struct gre_base_hdr *greh; 894 895 iph = skb_push(skb, t->hlen + sizeof(*iph)); 896 greh = (struct gre_base_hdr *)(iph+1); 897 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags); 898 greh->protocol = htons(type); 899 900 memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); 901 902 /* Set the source hardware address. */ 903 if (saddr) 904 memcpy(&iph->saddr, saddr, 4); 905 if (daddr) 906 memcpy(&iph->daddr, daddr, 4); 907 if (iph->daddr) 908 return t->hlen + sizeof(*iph); 909 910 return -(t->hlen + sizeof(*iph)); 911 } 912 913 static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) 914 { 915 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); 916 memcpy(haddr, &iph->saddr, 4); 917 return 4; 918 } 919 920 static const struct header_ops ipgre_header_ops = { 921 .create = ipgre_header, 922 .parse = ipgre_header_parse, 923 }; 924 925 #ifdef CONFIG_NET_IPGRE_BROADCAST 926 static int ipgre_open(struct net_device *dev) 927 { 928 struct ip_tunnel *t = netdev_priv(dev); 929 930 if (ipv4_is_multicast(t->parms.iph.daddr)) { 931 struct flowi4 fl4 = { 932 .flowi4_oif = t->parms.link, 933 .flowi4_tos = inet_dscp_to_dsfield(ip4h_dscp(&t->parms.iph)), 934 .flowi4_scope = RT_SCOPE_UNIVERSE, 935 .flowi4_proto = IPPROTO_GRE, 936 .saddr = t->parms.iph.saddr, 937 .daddr = t->parms.iph.daddr, 938 .fl4_gre_key = t->parms.o_key, 939 }; 940 struct rtable *rt; 941 942 rt = ip_route_output_key(t->net, &fl4); 943 if (IS_ERR(rt)) 944 return -EADDRNOTAVAIL; 945 dev = rt->dst.dev; 946 ip_rt_put(rt); 947 if (!__in_dev_get_rtnl(dev)) 948 return -EADDRNOTAVAIL; 949 t->mlink = dev->ifindex; 950 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); 951 } 952 return 0; 953 } 954 955 static int ipgre_close(struct net_device *dev) 956 { 957 struct ip_tunnel *t = netdev_priv(dev); 958 959 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { 960 struct in_device *in_dev; 961 in_dev = inetdev_by_index(t->net, t->mlink); 962 if (in_dev) 963 ip_mc_dec_group(in_dev, t->parms.iph.daddr); 964 } 965 return 0; 966 } 967 #endif 968 969 static const struct net_device_ops ipgre_netdev_ops = { 970 .ndo_init = ipgre_tunnel_init, 971 .ndo_uninit = ip_tunnel_uninit, 972 #ifdef CONFIG_NET_IPGRE_BROADCAST 973 .ndo_open = ipgre_open, 974 .ndo_stop = ipgre_close, 975 #endif 976 .ndo_start_xmit = ipgre_xmit, 977 .ndo_siocdevprivate = ip_tunnel_siocdevprivate, 978 .ndo_change_mtu = ip_tunnel_change_mtu, 979 .ndo_get_stats64 = dev_get_tstats64, 980 .ndo_get_iflink = ip_tunnel_get_iflink, 981 .ndo_tunnel_ctl = ipgre_tunnel_ctl, 982 }; 983 984 #define GRE_FEATURES (NETIF_F_SG | \ 985 NETIF_F_FRAGLIST | \ 986 NETIF_F_HIGHDMA | \ 987 NETIF_F_HW_CSUM) 988 989 static void ipgre_tunnel_setup(struct net_device *dev) 990 { 991 dev->netdev_ops = &ipgre_netdev_ops; 992 dev->type = ARPHRD_IPGRE; 993 ip_tunnel_setup(dev, ipgre_net_id); 994 } 995 996 static void __gre_tunnel_init(struct net_device *dev) 997 { 998 struct ip_tunnel *tunnel; 999 1000 tunnel = netdev_priv(dev); 1001 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 1002 tunnel->parms.iph.protocol = IPPROTO_GRE; 1003 1004 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 1005 dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph); 1006 1007 dev->features |= GRE_FEATURES; 1008 dev->hw_features |= GRE_FEATURES; 1009 1010 /* TCP offload with GRE SEQ is not supported, nor can we support 2 1011 * levels of outer headers requiring an update. 1012 */ 1013 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags)) 1014 return; 1015 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) && 1016 tunnel->encap.type != TUNNEL_ENCAP_NONE) 1017 return; 1018 1019 dev->features |= NETIF_F_GSO_SOFTWARE; 1020 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 1021 1022 dev->lltx = true; 1023 } 1024 1025 static int ipgre_tunnel_init(struct net_device *dev) 1026 { 1027 struct ip_tunnel *tunnel = netdev_priv(dev); 1028 struct iphdr *iph = &tunnel->parms.iph; 1029 1030 __gre_tunnel_init(dev); 1031 1032 __dev_addr_set(dev, &iph->saddr, 4); 1033 memcpy(dev->broadcast, &iph->daddr, 4); 1034 1035 dev->flags = IFF_NOARP; 1036 netif_keep_dst(dev); 1037 dev->addr_len = 4; 1038 1039 if (iph->daddr && !tunnel->collect_md) { 1040 #ifdef CONFIG_NET_IPGRE_BROADCAST 1041 if (ipv4_is_multicast(iph->daddr)) { 1042 if (!iph->saddr) 1043 return -EINVAL; 1044 dev->flags = IFF_BROADCAST; 1045 dev->header_ops = &ipgre_header_ops; 1046 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1047 dev->needed_headroom = 0; 1048 } 1049 #endif 1050 } else if (!tunnel->collect_md) { 1051 dev->header_ops = &ipgre_header_ops; 1052 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1053 dev->needed_headroom = 0; 1054 } 1055 1056 return ip_tunnel_init(dev); 1057 } 1058 1059 static const struct gre_protocol ipgre_protocol = { 1060 .handler = gre_rcv, 1061 .err_handler = gre_err, 1062 }; 1063 1064 static int __net_init ipgre_init_net(struct net *net) 1065 { 1066 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); 1067 } 1068 1069 static void __net_exit ipgre_exit_rtnl(struct net *net, 1070 struct list_head *dev_to_kill) 1071 { 1072 ip_tunnel_delete_net(net, ipgre_net_id, &ipgre_link_ops, dev_to_kill); 1073 } 1074 1075 static struct pernet_operations ipgre_net_ops = { 1076 .init = ipgre_init_net, 1077 .exit_rtnl = ipgre_exit_rtnl, 1078 .id = &ipgre_net_id, 1079 .size = sizeof(struct ip_tunnel_net), 1080 }; 1081 1082 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1083 struct netlink_ext_ack *extack) 1084 { 1085 __be16 flags; 1086 1087 if (!data) 1088 return 0; 1089 1090 flags = 0; 1091 if (data[IFLA_GRE_IFLAGS]) 1092 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1093 if (data[IFLA_GRE_OFLAGS]) 1094 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1095 if (flags & (GRE_VERSION|GRE_ROUTING)) 1096 return -EINVAL; 1097 1098 if (data[IFLA_GRE_COLLECT_METADATA] && 1099 data[IFLA_GRE_ENCAP_TYPE] && 1100 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) 1101 return -EINVAL; 1102 1103 return 0; 1104 } 1105 1106 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1107 struct netlink_ext_ack *extack) 1108 { 1109 __be32 daddr; 1110 1111 if (tb[IFLA_ADDRESS]) { 1112 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1113 return -EINVAL; 1114 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1115 return -EADDRNOTAVAIL; 1116 } 1117 1118 if (!data) 1119 goto out; 1120 1121 if (data[IFLA_GRE_REMOTE]) { 1122 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); 1123 if (!daddr) 1124 return -EINVAL; 1125 } 1126 1127 out: 1128 return ipgre_tunnel_validate(tb, data, extack); 1129 } 1130 1131 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], 1132 struct netlink_ext_ack *extack) 1133 { 1134 __be16 flags = 0; 1135 int ret; 1136 1137 if (!data) 1138 return 0; 1139 1140 ret = ipgre_tap_validate(tb, data, extack); 1141 if (ret) 1142 return ret; 1143 1144 if (data[IFLA_GRE_ERSPAN_VER] && 1145 nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) 1146 return 0; 1147 1148 /* ERSPAN type II/III should only have GRE sequence and key flag */ 1149 if (data[IFLA_GRE_OFLAGS]) 1150 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1151 if (data[IFLA_GRE_IFLAGS]) 1152 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1153 if (!data[IFLA_GRE_COLLECT_METADATA] && 1154 flags != (GRE_SEQ | GRE_KEY)) 1155 return -EINVAL; 1156 1157 /* ERSPAN Session ID only has 10-bit. Since we reuse 1158 * 32-bit key field as ID, check it's range. 1159 */ 1160 if (data[IFLA_GRE_IKEY] && 1161 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK)) 1162 return -EINVAL; 1163 1164 if (data[IFLA_GRE_OKEY] && 1165 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK)) 1166 return -EINVAL; 1167 1168 return 0; 1169 } 1170 1171 static int ipgre_netlink_parms(struct net_device *dev, 1172 struct nlattr *data[], 1173 struct nlattr *tb[], 1174 struct ip_tunnel_parm_kern *parms, 1175 __u32 *fwmark) 1176 { 1177 struct ip_tunnel *t = netdev_priv(dev); 1178 1179 memset(parms, 0, sizeof(*parms)); 1180 1181 parms->iph.protocol = IPPROTO_GRE; 1182 1183 if (!data) 1184 return 0; 1185 1186 if (data[IFLA_GRE_LINK]) 1187 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1188 1189 if (data[IFLA_GRE_IFLAGS]) 1190 gre_flags_to_tnl_flags(parms->i_flags, 1191 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1192 1193 if (data[IFLA_GRE_OFLAGS]) 1194 gre_flags_to_tnl_flags(parms->o_flags, 1195 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1196 1197 if (data[IFLA_GRE_IKEY]) 1198 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1199 1200 if (data[IFLA_GRE_OKEY]) 1201 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1202 1203 if (data[IFLA_GRE_LOCAL]) 1204 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); 1205 1206 if (data[IFLA_GRE_REMOTE]) 1207 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); 1208 1209 if (data[IFLA_GRE_TTL]) 1210 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); 1211 1212 if (data[IFLA_GRE_TOS]) 1213 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); 1214 1215 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) { 1216 if (t->ignore_df) 1217 return -EINVAL; 1218 parms->iph.frag_off = htons(IP_DF); 1219 } 1220 1221 if (data[IFLA_GRE_COLLECT_METADATA]) { 1222 t->collect_md = true; 1223 if (dev->type == ARPHRD_IPGRE) 1224 dev->type = ARPHRD_NONE; 1225 } 1226 1227 if (data[IFLA_GRE_IGNORE_DF]) { 1228 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF]) 1229 && (parms->iph.frag_off & htons(IP_DF))) 1230 return -EINVAL; 1231 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]); 1232 } 1233 1234 if (data[IFLA_GRE_FWMARK]) 1235 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1236 1237 return 0; 1238 } 1239 1240 static int erspan_netlink_parms(struct net_device *dev, 1241 struct nlattr *data[], 1242 struct nlattr *tb[], 1243 struct ip_tunnel_parm_kern *parms, 1244 __u32 *fwmark) 1245 { 1246 struct ip_tunnel *t = netdev_priv(dev); 1247 int err; 1248 1249 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark); 1250 if (err) 1251 return err; 1252 if (!data) 1253 return 0; 1254 1255 if (data[IFLA_GRE_ERSPAN_VER]) { 1256 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); 1257 1258 if (t->erspan_ver > 2) 1259 return -EINVAL; 1260 } 1261 1262 if (t->erspan_ver == 1) { 1263 if (data[IFLA_GRE_ERSPAN_INDEX]) { 1264 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]); 1265 if (t->index & ~INDEX_MASK) 1266 return -EINVAL; 1267 } 1268 } else if (t->erspan_ver == 2) { 1269 if (data[IFLA_GRE_ERSPAN_DIR]) { 1270 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]); 1271 if (t->dir & ~(DIR_MASK >> DIR_OFFSET)) 1272 return -EINVAL; 1273 } 1274 if (data[IFLA_GRE_ERSPAN_HWID]) { 1275 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]); 1276 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET)) 1277 return -EINVAL; 1278 } 1279 } 1280 1281 return 0; 1282 } 1283 1284 /* This function returns true when ENCAP attributes are present in the nl msg */ 1285 static bool ipgre_netlink_encap_parms(struct nlattr *data[], 1286 struct ip_tunnel_encap *ipencap) 1287 { 1288 bool ret = false; 1289 1290 memset(ipencap, 0, sizeof(*ipencap)); 1291 1292 if (!data) 1293 return ret; 1294 1295 if (data[IFLA_GRE_ENCAP_TYPE]) { 1296 ret = true; 1297 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1298 } 1299 1300 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1301 ret = true; 1302 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1303 } 1304 1305 if (data[IFLA_GRE_ENCAP_SPORT]) { 1306 ret = true; 1307 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1308 } 1309 1310 if (data[IFLA_GRE_ENCAP_DPORT]) { 1311 ret = true; 1312 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1313 } 1314 1315 return ret; 1316 } 1317 1318 static int gre_tap_init(struct net_device *dev) 1319 { 1320 __gre_tunnel_init(dev); 1321 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1322 netif_keep_dst(dev); 1323 1324 return ip_tunnel_init(dev); 1325 } 1326 1327 static const struct net_device_ops gre_tap_netdev_ops = { 1328 .ndo_init = gre_tap_init, 1329 .ndo_uninit = ip_tunnel_uninit, 1330 .ndo_start_xmit = gre_tap_xmit, 1331 .ndo_set_mac_address = eth_mac_addr, 1332 .ndo_validate_addr = eth_validate_addr, 1333 .ndo_change_mtu = ip_tunnel_change_mtu, 1334 .ndo_get_stats64 = dev_get_tstats64, 1335 .ndo_get_iflink = ip_tunnel_get_iflink, 1336 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1337 }; 1338 1339 static int erspan_tunnel_init(struct net_device *dev) 1340 { 1341 struct ip_tunnel *tunnel = netdev_priv(dev); 1342 1343 if (tunnel->erspan_ver == 0) 1344 tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ 1345 else 1346 tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ 1347 1348 tunnel->parms.iph.protocol = IPPROTO_GRE; 1349 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + 1350 erspan_hdr_len(tunnel->erspan_ver); 1351 1352 dev->features |= GRE_FEATURES; 1353 dev->hw_features |= GRE_FEATURES; 1354 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1355 netif_keep_dst(dev); 1356 1357 return ip_tunnel_init(dev); 1358 } 1359 1360 static const struct net_device_ops erspan_netdev_ops = { 1361 .ndo_init = erspan_tunnel_init, 1362 .ndo_uninit = ip_tunnel_uninit, 1363 .ndo_start_xmit = erspan_xmit, 1364 .ndo_set_mac_address = eth_mac_addr, 1365 .ndo_validate_addr = eth_validate_addr, 1366 .ndo_change_mtu = ip_tunnel_change_mtu, 1367 .ndo_get_stats64 = dev_get_tstats64, 1368 .ndo_get_iflink = ip_tunnel_get_iflink, 1369 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1370 }; 1371 1372 static void ipgre_tap_setup(struct net_device *dev) 1373 { 1374 ether_setup(dev); 1375 dev->max_mtu = 0; 1376 dev->netdev_ops = &gre_tap_netdev_ops; 1377 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1378 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1379 ip_tunnel_setup(dev, gre_tap_net_id); 1380 } 1381 1382 static int 1383 ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[]) 1384 { 1385 struct ip_tunnel_encap ipencap; 1386 1387 if (ipgre_netlink_encap_parms(data, &ipencap)) { 1388 struct ip_tunnel *t = netdev_priv(dev); 1389 int err = ip_tunnel_encap_setup(t, &ipencap); 1390 1391 if (err < 0) 1392 return err; 1393 } 1394 1395 return 0; 1396 } 1397 1398 static int ipgre_newlink(struct net_device *dev, 1399 struct rtnl_newlink_params *params, 1400 struct netlink_ext_ack *extack) 1401 { 1402 struct nlattr **data = params->data; 1403 struct nlattr **tb = params->tb; 1404 struct ip_tunnel_parm_kern p; 1405 __u32 fwmark = 0; 1406 int err; 1407 1408 err = ipgre_newlink_encap_setup(dev, data); 1409 if (err) 1410 return err; 1411 1412 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1413 if (err < 0) 1414 return err; 1415 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1416 fwmark); 1417 } 1418 1419 static int erspan_newlink(struct net_device *dev, 1420 struct rtnl_newlink_params *params, 1421 struct netlink_ext_ack *extack) 1422 { 1423 struct nlattr **data = params->data; 1424 struct nlattr **tb = params->tb; 1425 struct ip_tunnel_parm_kern p; 1426 __u32 fwmark = 0; 1427 int err; 1428 1429 err = ipgre_newlink_encap_setup(dev, data); 1430 if (err) 1431 return err; 1432 1433 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1434 if (err) 1435 return err; 1436 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1437 fwmark); 1438 } 1439 1440 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], 1441 struct nlattr *data[], 1442 struct netlink_ext_ack *extack) 1443 { 1444 struct ip_tunnel *t = netdev_priv(dev); 1445 struct ip_tunnel_parm_kern p; 1446 __u32 fwmark = t->fwmark; 1447 int err; 1448 1449 err = ipgre_newlink_encap_setup(dev, data); 1450 if (err) 1451 return err; 1452 1453 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1454 if (err < 0) 1455 return err; 1456 1457 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1458 if (err < 0) 1459 return err; 1460 1461 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1462 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1463 1464 ipgre_link_update(dev, !tb[IFLA_MTU]); 1465 1466 return 0; 1467 } 1468 1469 static int erspan_changelink(struct net_device *dev, struct nlattr *tb[], 1470 struct nlattr *data[], 1471 struct netlink_ext_ack *extack) 1472 { 1473 struct ip_tunnel *t = netdev_priv(dev); 1474 struct ip_tunnel_parm_kern p; 1475 __u32 fwmark = t->fwmark; 1476 int err; 1477 1478 err = ipgre_newlink_encap_setup(dev, data); 1479 if (err) 1480 return err; 1481 1482 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1483 if (err < 0) 1484 return err; 1485 1486 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1487 if (err < 0) 1488 return err; 1489 1490 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1491 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1492 1493 return 0; 1494 } 1495 1496 static size_t ipgre_get_size(const struct net_device *dev) 1497 { 1498 return 1499 /* IFLA_GRE_LINK */ 1500 nla_total_size(4) + 1501 /* IFLA_GRE_IFLAGS */ 1502 nla_total_size(2) + 1503 /* IFLA_GRE_OFLAGS */ 1504 nla_total_size(2) + 1505 /* IFLA_GRE_IKEY */ 1506 nla_total_size(4) + 1507 /* IFLA_GRE_OKEY */ 1508 nla_total_size(4) + 1509 /* IFLA_GRE_LOCAL */ 1510 nla_total_size(4) + 1511 /* IFLA_GRE_REMOTE */ 1512 nla_total_size(4) + 1513 /* IFLA_GRE_TTL */ 1514 nla_total_size(1) + 1515 /* IFLA_GRE_TOS */ 1516 nla_total_size(1) + 1517 /* IFLA_GRE_PMTUDISC */ 1518 nla_total_size(1) + 1519 /* IFLA_GRE_ENCAP_TYPE */ 1520 nla_total_size(2) + 1521 /* IFLA_GRE_ENCAP_FLAGS */ 1522 nla_total_size(2) + 1523 /* IFLA_GRE_ENCAP_SPORT */ 1524 nla_total_size(2) + 1525 /* IFLA_GRE_ENCAP_DPORT */ 1526 nla_total_size(2) + 1527 /* IFLA_GRE_COLLECT_METADATA */ 1528 nla_total_size(0) + 1529 /* IFLA_GRE_IGNORE_DF */ 1530 nla_total_size(1) + 1531 /* IFLA_GRE_FWMARK */ 1532 nla_total_size(4) + 1533 /* IFLA_GRE_ERSPAN_INDEX */ 1534 nla_total_size(4) + 1535 /* IFLA_GRE_ERSPAN_VER */ 1536 nla_total_size(1) + 1537 /* IFLA_GRE_ERSPAN_DIR */ 1538 nla_total_size(1) + 1539 /* IFLA_GRE_ERSPAN_HWID */ 1540 nla_total_size(2) + 1541 0; 1542 } 1543 1544 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1545 { 1546 struct ip_tunnel *t = netdev_priv(dev); 1547 struct ip_tunnel_parm_kern *p = &t->parms; 1548 IP_TUNNEL_DECLARE_FLAGS(o_flags); 1549 1550 ip_tunnel_flags_copy(o_flags, p->o_flags); 1551 1552 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1553 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1554 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1555 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1556 gre_tnl_flags_to_gre_flags(o_flags)) || 1557 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1558 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1559 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || 1560 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || 1561 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || 1562 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || 1563 nla_put_u8(skb, IFLA_GRE_PMTUDISC, 1564 !!(p->iph.frag_off & htons(IP_DF))) || 1565 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark)) 1566 goto nla_put_failure; 1567 1568 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1569 t->encap.type) || 1570 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1571 t->encap.sport) || 1572 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1573 t->encap.dport) || 1574 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1575 t->encap.flags)) 1576 goto nla_put_failure; 1577 1578 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df)) 1579 goto nla_put_failure; 1580 1581 if (t->collect_md) { 1582 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) 1583 goto nla_put_failure; 1584 } 1585 1586 return 0; 1587 1588 nla_put_failure: 1589 return -EMSGSIZE; 1590 } 1591 1592 static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev) 1593 { 1594 struct ip_tunnel *t = netdev_priv(dev); 1595 1596 if (t->erspan_ver <= 2) { 1597 if (t->erspan_ver != 0 && !t->collect_md) 1598 __set_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags); 1599 1600 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) 1601 goto nla_put_failure; 1602 1603 if (t->erspan_ver == 1) { 1604 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) 1605 goto nla_put_failure; 1606 } else if (t->erspan_ver == 2) { 1607 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) 1608 goto nla_put_failure; 1609 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid)) 1610 goto nla_put_failure; 1611 } 1612 } 1613 1614 return ipgre_fill_info(skb, dev); 1615 1616 nla_put_failure: 1617 return -EMSGSIZE; 1618 } 1619 1620 static void erspan_setup(struct net_device *dev) 1621 { 1622 struct ip_tunnel *t = netdev_priv(dev); 1623 1624 ether_setup(dev); 1625 dev->max_mtu = 0; 1626 dev->netdev_ops = &erspan_netdev_ops; 1627 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1628 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1629 ip_tunnel_setup(dev, erspan_net_id); 1630 t->erspan_ver = 1; 1631 } 1632 1633 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { 1634 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1635 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1636 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1637 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1638 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1639 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) }, 1640 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, 1641 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1642 [IFLA_GRE_TOS] = { .type = NLA_U8 }, 1643 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, 1644 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1645 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1646 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1647 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1648 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, 1649 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 }, 1650 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1651 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 }, 1652 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 }, 1653 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 }, 1654 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 }, 1655 }; 1656 1657 static struct rtnl_link_ops ipgre_link_ops __read_mostly = { 1658 .kind = "gre", 1659 .maxtype = IFLA_GRE_MAX, 1660 .policy = ipgre_policy, 1661 .priv_size = sizeof(struct ip_tunnel), 1662 .setup = ipgre_tunnel_setup, 1663 .validate = ipgre_tunnel_validate, 1664 .newlink = ipgre_newlink, 1665 .changelink = ipgre_changelink, 1666 .dellink = ip_tunnel_dellink, 1667 .get_size = ipgre_get_size, 1668 .fill_info = ipgre_fill_info, 1669 .get_link_net = ip_tunnel_get_link_net, 1670 }; 1671 1672 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { 1673 .kind = "gretap", 1674 .maxtype = IFLA_GRE_MAX, 1675 .policy = ipgre_policy, 1676 .priv_size = sizeof(struct ip_tunnel), 1677 .setup = ipgre_tap_setup, 1678 .validate = ipgre_tap_validate, 1679 .newlink = ipgre_newlink, 1680 .changelink = ipgre_changelink, 1681 .dellink = ip_tunnel_dellink, 1682 .get_size = ipgre_get_size, 1683 .fill_info = ipgre_fill_info, 1684 .get_link_net = ip_tunnel_get_link_net, 1685 }; 1686 1687 static struct rtnl_link_ops erspan_link_ops __read_mostly = { 1688 .kind = "erspan", 1689 .maxtype = IFLA_GRE_MAX, 1690 .policy = ipgre_policy, 1691 .priv_size = sizeof(struct ip_tunnel), 1692 .setup = erspan_setup, 1693 .validate = erspan_validate, 1694 .newlink = erspan_newlink, 1695 .changelink = erspan_changelink, 1696 .dellink = ip_tunnel_dellink, 1697 .get_size = ipgre_get_size, 1698 .fill_info = erspan_fill_info, 1699 .get_link_net = ip_tunnel_get_link_net, 1700 }; 1701 1702 struct net_device *gretap_fb_dev_create(struct net *net, const char *name, 1703 u8 name_assign_type) 1704 { 1705 struct rtnl_newlink_params params = { .src_net = net }; 1706 struct nlattr *tb[IFLA_MAX + 1]; 1707 struct net_device *dev; 1708 LIST_HEAD(list_kill); 1709 struct ip_tunnel *t; 1710 int err; 1711 1712 memset(&tb, 0, sizeof(tb)); 1713 params.tb = tb; 1714 1715 dev = rtnl_create_link(net, name, name_assign_type, 1716 &ipgre_tap_ops, tb, NULL); 1717 if (IS_ERR(dev)) 1718 return dev; 1719 1720 /* Configure flow based GRE device. */ 1721 t = netdev_priv(dev); 1722 t->collect_md = true; 1723 1724 err = ipgre_newlink(dev, ¶ms, NULL); 1725 if (err < 0) { 1726 free_netdev(dev); 1727 return ERR_PTR(err); 1728 } 1729 1730 /* openvswitch users expect packet sizes to be unrestricted, 1731 * so set the largest MTU we can. 1732 */ 1733 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); 1734 if (err) 1735 goto out; 1736 1737 err = rtnl_configure_link(dev, NULL, 0, NULL); 1738 if (err < 0) 1739 goto out; 1740 1741 return dev; 1742 out: 1743 ip_tunnel_dellink(dev, &list_kill); 1744 unregister_netdevice_many(&list_kill); 1745 return ERR_PTR(err); 1746 } 1747 EXPORT_SYMBOL_GPL(gretap_fb_dev_create); 1748 1749 static int __net_init ipgre_tap_init_net(struct net *net) 1750 { 1751 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); 1752 } 1753 1754 static void __net_exit ipgre_tap_exit_rtnl(struct net *net, 1755 struct list_head *dev_to_kill) 1756 { 1757 ip_tunnel_delete_net(net, gre_tap_net_id, &ipgre_tap_ops, dev_to_kill); 1758 } 1759 1760 static struct pernet_operations ipgre_tap_net_ops = { 1761 .init = ipgre_tap_init_net, 1762 .exit_rtnl = ipgre_tap_exit_rtnl, 1763 .id = &gre_tap_net_id, 1764 .size = sizeof(struct ip_tunnel_net), 1765 }; 1766 1767 static int __net_init erspan_init_net(struct net *net) 1768 { 1769 return ip_tunnel_init_net(net, erspan_net_id, 1770 &erspan_link_ops, "erspan0"); 1771 } 1772 1773 static void __net_exit erspan_exit_rtnl(struct net *net, 1774 struct list_head *dev_to_kill) 1775 { 1776 ip_tunnel_delete_net(net, erspan_net_id, &erspan_link_ops, dev_to_kill); 1777 } 1778 1779 static struct pernet_operations erspan_net_ops = { 1780 .init = erspan_init_net, 1781 .exit_rtnl = erspan_exit_rtnl, 1782 .id = &erspan_net_id, 1783 .size = sizeof(struct ip_tunnel_net), 1784 }; 1785 1786 static int __init ipgre_init(void) 1787 { 1788 int err; 1789 1790 pr_info("GRE over IPv4 tunneling driver\n"); 1791 1792 err = register_pernet_device(&ipgre_net_ops); 1793 if (err < 0) 1794 return err; 1795 1796 err = register_pernet_device(&ipgre_tap_net_ops); 1797 if (err < 0) 1798 goto pnet_tap_failed; 1799 1800 err = register_pernet_device(&erspan_net_ops); 1801 if (err < 0) 1802 goto pnet_erspan_failed; 1803 1804 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); 1805 if (err < 0) { 1806 pr_info("%s: can't add protocol\n", __func__); 1807 goto add_proto_failed; 1808 } 1809 1810 err = rtnl_link_register(&ipgre_link_ops); 1811 if (err < 0) 1812 goto rtnl_link_failed; 1813 1814 err = rtnl_link_register(&ipgre_tap_ops); 1815 if (err < 0) 1816 goto tap_ops_failed; 1817 1818 err = rtnl_link_register(&erspan_link_ops); 1819 if (err < 0) 1820 goto erspan_link_failed; 1821 1822 return 0; 1823 1824 erspan_link_failed: 1825 rtnl_link_unregister(&ipgre_tap_ops); 1826 tap_ops_failed: 1827 rtnl_link_unregister(&ipgre_link_ops); 1828 rtnl_link_failed: 1829 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1830 add_proto_failed: 1831 unregister_pernet_device(&erspan_net_ops); 1832 pnet_erspan_failed: 1833 unregister_pernet_device(&ipgre_tap_net_ops); 1834 pnet_tap_failed: 1835 unregister_pernet_device(&ipgre_net_ops); 1836 return err; 1837 } 1838 1839 static void __exit ipgre_fini(void) 1840 { 1841 rtnl_link_unregister(&ipgre_tap_ops); 1842 rtnl_link_unregister(&ipgre_link_ops); 1843 rtnl_link_unregister(&erspan_link_ops); 1844 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1845 unregister_pernet_device(&ipgre_tap_net_ops); 1846 unregister_pernet_device(&ipgre_net_ops); 1847 unregister_pernet_device(&erspan_net_ops); 1848 } 1849 1850 module_init(ipgre_init); 1851 module_exit(ipgre_fini); 1852 MODULE_DESCRIPTION("IPv4 GRE tunnels over IP library"); 1853 MODULE_LICENSE("GPL"); 1854 MODULE_ALIAS_RTNL_LINK("gre"); 1855 MODULE_ALIAS_RTNL_LINK("gretap"); 1856 MODULE_ALIAS_RTNL_LINK("erspan"); 1857 MODULE_ALIAS_NETDEV("gre0"); 1858 MODULE_ALIAS_NETDEV("gretap0"); 1859 MODULE_ALIAS_NETDEV("erspan0"); 1860