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 gre_base_hdr *greh; 895 struct iphdr *iph; 896 int needed; 897 898 needed = t->hlen + sizeof(*iph); 899 if (skb_headroom(skb) < needed && 900 pskb_expand_head(skb, HH_DATA_ALIGN(needed - skb_headroom(skb)), 901 0, GFP_ATOMIC)) 902 return -needed; 903 904 iph = skb_push(skb, needed); 905 greh = (struct gre_base_hdr *)(iph+1); 906 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags); 907 greh->protocol = htons(type); 908 909 memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); 910 911 /* Set the source hardware address. */ 912 if (saddr) 913 memcpy(&iph->saddr, saddr, 4); 914 if (daddr) 915 memcpy(&iph->daddr, daddr, 4); 916 if (iph->daddr) 917 return t->hlen + sizeof(*iph); 918 919 return -(t->hlen + sizeof(*iph)); 920 } 921 922 static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) 923 { 924 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); 925 memcpy(haddr, &iph->saddr, 4); 926 return 4; 927 } 928 929 static const struct header_ops ipgre_header_ops = { 930 .create = ipgre_header, 931 .parse = ipgre_header_parse, 932 }; 933 934 #ifdef CONFIG_NET_IPGRE_BROADCAST 935 static int ipgre_open(struct net_device *dev) 936 { 937 struct ip_tunnel *t = netdev_priv(dev); 938 939 if (ipv4_is_multicast(t->parms.iph.daddr)) { 940 struct flowi4 fl4 = { 941 .flowi4_oif = t->parms.link, 942 .flowi4_dscp = ip4h_dscp(&t->parms.iph), 943 .flowi4_scope = RT_SCOPE_UNIVERSE, 944 .flowi4_proto = IPPROTO_GRE, 945 .saddr = t->parms.iph.saddr, 946 .daddr = t->parms.iph.daddr, 947 .fl4_gre_key = t->parms.o_key, 948 }; 949 struct rtable *rt; 950 951 rt = ip_route_output_key(t->net, &fl4); 952 if (IS_ERR(rt)) 953 return -EADDRNOTAVAIL; 954 dev = rt->dst.dev; 955 ip_rt_put(rt); 956 if (!__in_dev_get_rtnl(dev)) 957 return -EADDRNOTAVAIL; 958 t->mlink = dev->ifindex; 959 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); 960 } 961 return 0; 962 } 963 964 static int ipgre_close(struct net_device *dev) 965 { 966 struct ip_tunnel *t = netdev_priv(dev); 967 968 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { 969 struct in_device *in_dev; 970 in_dev = inetdev_by_index(t->net, t->mlink); 971 if (in_dev) 972 ip_mc_dec_group(in_dev, t->parms.iph.daddr); 973 } 974 return 0; 975 } 976 #endif 977 978 static const struct net_device_ops ipgre_netdev_ops = { 979 .ndo_init = ipgre_tunnel_init, 980 .ndo_uninit = ip_tunnel_uninit, 981 #ifdef CONFIG_NET_IPGRE_BROADCAST 982 .ndo_open = ipgre_open, 983 .ndo_stop = ipgre_close, 984 #endif 985 .ndo_start_xmit = ipgre_xmit, 986 .ndo_siocdevprivate = ip_tunnel_siocdevprivate, 987 .ndo_change_mtu = ip_tunnel_change_mtu, 988 .ndo_get_stats64 = dev_get_tstats64, 989 .ndo_get_iflink = ip_tunnel_get_iflink, 990 .ndo_tunnel_ctl = ipgre_tunnel_ctl, 991 }; 992 993 #define GRE_FEATURES (NETIF_F_SG | \ 994 NETIF_F_FRAGLIST | \ 995 NETIF_F_HIGHDMA | \ 996 NETIF_F_HW_CSUM) 997 998 static void ipgre_tunnel_setup(struct net_device *dev) 999 { 1000 dev->netdev_ops = &ipgre_netdev_ops; 1001 dev->type = ARPHRD_IPGRE; 1002 ip_tunnel_setup(dev, ipgre_net_id); 1003 } 1004 1005 static void __gre_tunnel_init(struct net_device *dev) 1006 { 1007 struct ip_tunnel *tunnel; 1008 1009 tunnel = netdev_priv(dev); 1010 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 1011 tunnel->parms.iph.protocol = IPPROTO_GRE; 1012 1013 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 1014 dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph); 1015 1016 dev->features |= GRE_FEATURES; 1017 dev->hw_features |= GRE_FEATURES; 1018 1019 /* TCP offload with GRE SEQ is not supported, nor can we support 2 1020 * levels of outer headers requiring an update. 1021 */ 1022 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags)) 1023 return; 1024 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) && 1025 tunnel->encap.type != TUNNEL_ENCAP_NONE) 1026 return; 1027 1028 dev->features |= NETIF_F_GSO_SOFTWARE; 1029 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 1030 1031 dev->lltx = true; 1032 } 1033 1034 static int ipgre_tunnel_init(struct net_device *dev) 1035 { 1036 struct ip_tunnel *tunnel = netdev_priv(dev); 1037 struct iphdr *iph = &tunnel->parms.iph; 1038 1039 __gre_tunnel_init(dev); 1040 1041 __dev_addr_set(dev, &iph->saddr, 4); 1042 memcpy(dev->broadcast, &iph->daddr, 4); 1043 1044 dev->flags = IFF_NOARP; 1045 netif_keep_dst(dev); 1046 dev->addr_len = 4; 1047 1048 if (iph->daddr && !tunnel->collect_md) { 1049 #ifdef CONFIG_NET_IPGRE_BROADCAST 1050 if (ipv4_is_multicast(iph->daddr)) { 1051 if (!iph->saddr) 1052 return -EINVAL; 1053 dev->flags = IFF_BROADCAST; 1054 dev->header_ops = &ipgre_header_ops; 1055 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1056 dev->needed_headroom = 0; 1057 } 1058 #endif 1059 } else if (!tunnel->collect_md) { 1060 dev->header_ops = &ipgre_header_ops; 1061 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1062 dev->needed_headroom = 0; 1063 } 1064 1065 return ip_tunnel_init(dev); 1066 } 1067 1068 static const struct gre_protocol ipgre_protocol = { 1069 .handler = gre_rcv, 1070 .err_handler = gre_err, 1071 }; 1072 1073 static int __net_init ipgre_init_net(struct net *net) 1074 { 1075 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); 1076 } 1077 1078 static void __net_exit ipgre_exit_rtnl(struct net *net, 1079 struct list_head *dev_to_kill) 1080 { 1081 ip_tunnel_delete_net(net, ipgre_net_id, &ipgre_link_ops, dev_to_kill); 1082 } 1083 1084 static struct pernet_operations ipgre_net_ops = { 1085 .init = ipgre_init_net, 1086 .exit_rtnl = ipgre_exit_rtnl, 1087 .id = &ipgre_net_id, 1088 .size = sizeof(struct ip_tunnel_net), 1089 }; 1090 1091 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1092 struct netlink_ext_ack *extack) 1093 { 1094 __be16 flags; 1095 1096 if (!data) 1097 return 0; 1098 1099 flags = 0; 1100 if (data[IFLA_GRE_IFLAGS]) 1101 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1102 if (data[IFLA_GRE_OFLAGS]) 1103 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1104 if (flags & (GRE_VERSION|GRE_ROUTING)) 1105 return -EINVAL; 1106 1107 if (data[IFLA_GRE_COLLECT_METADATA] && 1108 data[IFLA_GRE_ENCAP_TYPE] && 1109 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) 1110 return -EINVAL; 1111 1112 return 0; 1113 } 1114 1115 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1116 struct netlink_ext_ack *extack) 1117 { 1118 __be32 daddr; 1119 1120 if (tb[IFLA_ADDRESS]) { 1121 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1122 return -EINVAL; 1123 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1124 return -EADDRNOTAVAIL; 1125 } 1126 1127 if (!data) 1128 goto out; 1129 1130 if (data[IFLA_GRE_REMOTE]) { 1131 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); 1132 if (!daddr) 1133 return -EINVAL; 1134 } 1135 1136 out: 1137 return ipgre_tunnel_validate(tb, data, extack); 1138 } 1139 1140 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], 1141 struct netlink_ext_ack *extack) 1142 { 1143 __be16 flags = 0; 1144 int ret; 1145 1146 if (!data) 1147 return 0; 1148 1149 ret = ipgre_tap_validate(tb, data, extack); 1150 if (ret) 1151 return ret; 1152 1153 if (data[IFLA_GRE_ERSPAN_VER] && 1154 nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) 1155 return 0; 1156 1157 /* ERSPAN type II/III should only have GRE sequence and key flag */ 1158 if (data[IFLA_GRE_OFLAGS]) 1159 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1160 if (data[IFLA_GRE_IFLAGS]) 1161 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1162 if (!data[IFLA_GRE_COLLECT_METADATA] && 1163 flags != (GRE_SEQ | GRE_KEY)) 1164 return -EINVAL; 1165 1166 /* ERSPAN Session ID only has 10-bit. Since we reuse 1167 * 32-bit key field as ID, check it's range. 1168 */ 1169 if (data[IFLA_GRE_IKEY] && 1170 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK)) 1171 return -EINVAL; 1172 1173 if (data[IFLA_GRE_OKEY] && 1174 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK)) 1175 return -EINVAL; 1176 1177 return 0; 1178 } 1179 1180 static int ipgre_netlink_parms(struct net_device *dev, 1181 struct nlattr *data[], 1182 struct nlattr *tb[], 1183 struct ip_tunnel_parm_kern *parms, 1184 __u32 *fwmark) 1185 { 1186 struct ip_tunnel *t = netdev_priv(dev); 1187 1188 memset(parms, 0, sizeof(*parms)); 1189 1190 parms->iph.protocol = IPPROTO_GRE; 1191 1192 if (!data) 1193 return 0; 1194 1195 if (data[IFLA_GRE_LINK]) 1196 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1197 1198 if (data[IFLA_GRE_IFLAGS]) 1199 gre_flags_to_tnl_flags(parms->i_flags, 1200 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1201 1202 if (data[IFLA_GRE_OFLAGS]) 1203 gre_flags_to_tnl_flags(parms->o_flags, 1204 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1205 1206 if (data[IFLA_GRE_IKEY]) 1207 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1208 1209 if (data[IFLA_GRE_OKEY]) 1210 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1211 1212 if (data[IFLA_GRE_LOCAL]) 1213 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); 1214 1215 if (data[IFLA_GRE_REMOTE]) 1216 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); 1217 1218 if (data[IFLA_GRE_TTL]) 1219 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); 1220 1221 if (data[IFLA_GRE_TOS]) 1222 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); 1223 1224 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) { 1225 if (t->ignore_df) 1226 return -EINVAL; 1227 parms->iph.frag_off = htons(IP_DF); 1228 } 1229 1230 if (data[IFLA_GRE_COLLECT_METADATA]) { 1231 t->collect_md = true; 1232 if (dev->type == ARPHRD_IPGRE) 1233 dev->type = ARPHRD_NONE; 1234 } 1235 1236 if (data[IFLA_GRE_IGNORE_DF]) { 1237 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF]) 1238 && (parms->iph.frag_off & htons(IP_DF))) 1239 return -EINVAL; 1240 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]); 1241 } 1242 1243 if (data[IFLA_GRE_FWMARK]) 1244 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1245 1246 return 0; 1247 } 1248 1249 static int erspan_netlink_parms(struct net_device *dev, 1250 struct nlattr *data[], 1251 struct nlattr *tb[], 1252 struct ip_tunnel_parm_kern *parms, 1253 __u32 *fwmark) 1254 { 1255 struct ip_tunnel *t = netdev_priv(dev); 1256 int err; 1257 1258 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark); 1259 if (err) 1260 return err; 1261 if (!data) 1262 return 0; 1263 1264 if (data[IFLA_GRE_ERSPAN_VER]) { 1265 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); 1266 1267 if (t->erspan_ver > 2) 1268 return -EINVAL; 1269 } 1270 1271 if (t->erspan_ver == 1) { 1272 if (data[IFLA_GRE_ERSPAN_INDEX]) { 1273 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]); 1274 if (t->index & ~INDEX_MASK) 1275 return -EINVAL; 1276 } 1277 } else if (t->erspan_ver == 2) { 1278 if (data[IFLA_GRE_ERSPAN_DIR]) { 1279 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]); 1280 if (t->dir & ~(DIR_MASK >> DIR_OFFSET)) 1281 return -EINVAL; 1282 } 1283 if (data[IFLA_GRE_ERSPAN_HWID]) { 1284 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]); 1285 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET)) 1286 return -EINVAL; 1287 } 1288 } 1289 1290 return 0; 1291 } 1292 1293 /* This function returns true when ENCAP attributes are present in the nl msg */ 1294 static bool ipgre_netlink_encap_parms(struct nlattr *data[], 1295 struct ip_tunnel_encap *ipencap) 1296 { 1297 bool ret = false; 1298 1299 memset(ipencap, 0, sizeof(*ipencap)); 1300 1301 if (!data) 1302 return ret; 1303 1304 if (data[IFLA_GRE_ENCAP_TYPE]) { 1305 ret = true; 1306 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1307 } 1308 1309 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1310 ret = true; 1311 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1312 } 1313 1314 if (data[IFLA_GRE_ENCAP_SPORT]) { 1315 ret = true; 1316 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1317 } 1318 1319 if (data[IFLA_GRE_ENCAP_DPORT]) { 1320 ret = true; 1321 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1322 } 1323 1324 return ret; 1325 } 1326 1327 static int gre_tap_init(struct net_device *dev) 1328 { 1329 __gre_tunnel_init(dev); 1330 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1331 netif_keep_dst(dev); 1332 1333 return ip_tunnel_init(dev); 1334 } 1335 1336 static const struct net_device_ops gre_tap_netdev_ops = { 1337 .ndo_init = gre_tap_init, 1338 .ndo_uninit = ip_tunnel_uninit, 1339 .ndo_start_xmit = gre_tap_xmit, 1340 .ndo_set_mac_address = eth_mac_addr, 1341 .ndo_validate_addr = eth_validate_addr, 1342 .ndo_change_mtu = ip_tunnel_change_mtu, 1343 .ndo_get_stats64 = dev_get_tstats64, 1344 .ndo_get_iflink = ip_tunnel_get_iflink, 1345 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1346 }; 1347 1348 static int erspan_tunnel_init(struct net_device *dev) 1349 { 1350 struct ip_tunnel *tunnel = netdev_priv(dev); 1351 1352 if (tunnel->erspan_ver == 0) 1353 tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ 1354 else 1355 tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ 1356 1357 tunnel->parms.iph.protocol = IPPROTO_GRE; 1358 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + 1359 erspan_hdr_len(tunnel->erspan_ver); 1360 1361 dev->features |= GRE_FEATURES; 1362 dev->hw_features |= GRE_FEATURES; 1363 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1364 netif_keep_dst(dev); 1365 1366 return ip_tunnel_init(dev); 1367 } 1368 1369 static const struct net_device_ops erspan_netdev_ops = { 1370 .ndo_init = erspan_tunnel_init, 1371 .ndo_uninit = ip_tunnel_uninit, 1372 .ndo_start_xmit = erspan_xmit, 1373 .ndo_set_mac_address = eth_mac_addr, 1374 .ndo_validate_addr = eth_validate_addr, 1375 .ndo_change_mtu = ip_tunnel_change_mtu, 1376 .ndo_get_stats64 = dev_get_tstats64, 1377 .ndo_get_iflink = ip_tunnel_get_iflink, 1378 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1379 }; 1380 1381 static void ipgre_tap_setup(struct net_device *dev) 1382 { 1383 ether_setup(dev); 1384 dev->max_mtu = 0; 1385 dev->netdev_ops = &gre_tap_netdev_ops; 1386 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1387 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1388 ip_tunnel_setup(dev, gre_tap_net_id); 1389 } 1390 1391 static int 1392 ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[]) 1393 { 1394 struct ip_tunnel_encap ipencap; 1395 1396 if (ipgre_netlink_encap_parms(data, &ipencap)) { 1397 struct ip_tunnel *t = netdev_priv(dev); 1398 int err = ip_tunnel_encap_setup(t, &ipencap); 1399 1400 if (err < 0) 1401 return err; 1402 } 1403 1404 return 0; 1405 } 1406 1407 static int ipgre_newlink(struct net_device *dev, 1408 struct rtnl_newlink_params *params, 1409 struct netlink_ext_ack *extack) 1410 { 1411 struct nlattr **data = params->data; 1412 struct nlattr **tb = params->tb; 1413 struct ip_tunnel_parm_kern p; 1414 __u32 fwmark = 0; 1415 int err; 1416 1417 err = ipgre_newlink_encap_setup(dev, data); 1418 if (err) 1419 return err; 1420 1421 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1422 if (err < 0) 1423 return err; 1424 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1425 fwmark); 1426 } 1427 1428 static int erspan_newlink(struct net_device *dev, 1429 struct rtnl_newlink_params *params, 1430 struct netlink_ext_ack *extack) 1431 { 1432 struct nlattr **data = params->data; 1433 struct nlattr **tb = params->tb; 1434 struct ip_tunnel_parm_kern p; 1435 __u32 fwmark = 0; 1436 int err; 1437 1438 err = ipgre_newlink_encap_setup(dev, data); 1439 if (err) 1440 return err; 1441 1442 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1443 if (err) 1444 return err; 1445 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1446 fwmark); 1447 } 1448 1449 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], 1450 struct nlattr *data[], 1451 struct netlink_ext_ack *extack) 1452 { 1453 struct ip_tunnel *t = netdev_priv(dev); 1454 struct ip_tunnel_parm_kern p; 1455 __u32 fwmark = t->fwmark; 1456 int err; 1457 1458 err = ipgre_newlink_encap_setup(dev, data); 1459 if (err) 1460 return err; 1461 1462 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1463 if (err < 0) 1464 return err; 1465 1466 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1467 if (err < 0) 1468 return err; 1469 1470 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1471 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1472 1473 ipgre_link_update(dev, !tb[IFLA_MTU]); 1474 1475 return 0; 1476 } 1477 1478 static int erspan_changelink(struct net_device *dev, struct nlattr *tb[], 1479 struct nlattr *data[], 1480 struct netlink_ext_ack *extack) 1481 { 1482 struct ip_tunnel *t = netdev_priv(dev); 1483 struct ip_tunnel_parm_kern p; 1484 __u32 fwmark = t->fwmark; 1485 int err; 1486 1487 err = ipgre_newlink_encap_setup(dev, data); 1488 if (err) 1489 return err; 1490 1491 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1492 if (err < 0) 1493 return err; 1494 1495 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1496 if (err < 0) 1497 return err; 1498 1499 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1500 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1501 1502 return 0; 1503 } 1504 1505 static size_t ipgre_get_size(const struct net_device *dev) 1506 { 1507 return 1508 /* IFLA_GRE_LINK */ 1509 nla_total_size(4) + 1510 /* IFLA_GRE_IFLAGS */ 1511 nla_total_size(2) + 1512 /* IFLA_GRE_OFLAGS */ 1513 nla_total_size(2) + 1514 /* IFLA_GRE_IKEY */ 1515 nla_total_size(4) + 1516 /* IFLA_GRE_OKEY */ 1517 nla_total_size(4) + 1518 /* IFLA_GRE_LOCAL */ 1519 nla_total_size(4) + 1520 /* IFLA_GRE_REMOTE */ 1521 nla_total_size(4) + 1522 /* IFLA_GRE_TTL */ 1523 nla_total_size(1) + 1524 /* IFLA_GRE_TOS */ 1525 nla_total_size(1) + 1526 /* IFLA_GRE_PMTUDISC */ 1527 nla_total_size(1) + 1528 /* IFLA_GRE_ENCAP_TYPE */ 1529 nla_total_size(2) + 1530 /* IFLA_GRE_ENCAP_FLAGS */ 1531 nla_total_size(2) + 1532 /* IFLA_GRE_ENCAP_SPORT */ 1533 nla_total_size(2) + 1534 /* IFLA_GRE_ENCAP_DPORT */ 1535 nla_total_size(2) + 1536 /* IFLA_GRE_COLLECT_METADATA */ 1537 nla_total_size(0) + 1538 /* IFLA_GRE_IGNORE_DF */ 1539 nla_total_size(1) + 1540 /* IFLA_GRE_FWMARK */ 1541 nla_total_size(4) + 1542 /* IFLA_GRE_ERSPAN_INDEX */ 1543 nla_total_size(4) + 1544 /* IFLA_GRE_ERSPAN_VER */ 1545 nla_total_size(1) + 1546 /* IFLA_GRE_ERSPAN_DIR */ 1547 nla_total_size(1) + 1548 /* IFLA_GRE_ERSPAN_HWID */ 1549 nla_total_size(2) + 1550 0; 1551 } 1552 1553 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1554 { 1555 struct ip_tunnel *t = netdev_priv(dev); 1556 struct ip_tunnel_parm_kern *p = &t->parms; 1557 IP_TUNNEL_DECLARE_FLAGS(o_flags); 1558 1559 ip_tunnel_flags_copy(o_flags, p->o_flags); 1560 1561 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1562 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1563 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1564 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1565 gre_tnl_flags_to_gre_flags(o_flags)) || 1566 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1567 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1568 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || 1569 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || 1570 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || 1571 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || 1572 nla_put_u8(skb, IFLA_GRE_PMTUDISC, 1573 !!(p->iph.frag_off & htons(IP_DF))) || 1574 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark)) 1575 goto nla_put_failure; 1576 1577 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1578 t->encap.type) || 1579 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1580 t->encap.sport) || 1581 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1582 t->encap.dport) || 1583 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1584 t->encap.flags)) 1585 goto nla_put_failure; 1586 1587 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df)) 1588 goto nla_put_failure; 1589 1590 if (t->collect_md) { 1591 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) 1592 goto nla_put_failure; 1593 } 1594 1595 return 0; 1596 1597 nla_put_failure: 1598 return -EMSGSIZE; 1599 } 1600 1601 static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev) 1602 { 1603 struct ip_tunnel *t = netdev_priv(dev); 1604 1605 if (t->erspan_ver <= 2) { 1606 if (t->erspan_ver != 0 && !t->collect_md) 1607 __set_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags); 1608 1609 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) 1610 goto nla_put_failure; 1611 1612 if (t->erspan_ver == 1) { 1613 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) 1614 goto nla_put_failure; 1615 } else if (t->erspan_ver == 2) { 1616 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) 1617 goto nla_put_failure; 1618 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid)) 1619 goto nla_put_failure; 1620 } 1621 } 1622 1623 return ipgre_fill_info(skb, dev); 1624 1625 nla_put_failure: 1626 return -EMSGSIZE; 1627 } 1628 1629 static void erspan_setup(struct net_device *dev) 1630 { 1631 struct ip_tunnel *t = netdev_priv(dev); 1632 1633 ether_setup(dev); 1634 dev->max_mtu = 0; 1635 dev->netdev_ops = &erspan_netdev_ops; 1636 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1637 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1638 ip_tunnel_setup(dev, erspan_net_id); 1639 t->erspan_ver = 1; 1640 } 1641 1642 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { 1643 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1644 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1645 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1646 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1647 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1648 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) }, 1649 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, 1650 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1651 [IFLA_GRE_TOS] = { .type = NLA_U8 }, 1652 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, 1653 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1654 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1655 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1656 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1657 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, 1658 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 }, 1659 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1660 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 }, 1661 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 }, 1662 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 }, 1663 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 }, 1664 }; 1665 1666 static struct rtnl_link_ops ipgre_link_ops __read_mostly = { 1667 .kind = "gre", 1668 .maxtype = IFLA_GRE_MAX, 1669 .policy = ipgre_policy, 1670 .priv_size = sizeof(struct ip_tunnel), 1671 .setup = ipgre_tunnel_setup, 1672 .validate = ipgre_tunnel_validate, 1673 .newlink = ipgre_newlink, 1674 .changelink = ipgre_changelink, 1675 .dellink = ip_tunnel_dellink, 1676 .get_size = ipgre_get_size, 1677 .fill_info = ipgre_fill_info, 1678 .get_link_net = ip_tunnel_get_link_net, 1679 }; 1680 1681 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { 1682 .kind = "gretap", 1683 .maxtype = IFLA_GRE_MAX, 1684 .policy = ipgre_policy, 1685 .priv_size = sizeof(struct ip_tunnel), 1686 .setup = ipgre_tap_setup, 1687 .validate = ipgre_tap_validate, 1688 .newlink = ipgre_newlink, 1689 .changelink = ipgre_changelink, 1690 .dellink = ip_tunnel_dellink, 1691 .get_size = ipgre_get_size, 1692 .fill_info = ipgre_fill_info, 1693 .get_link_net = ip_tunnel_get_link_net, 1694 }; 1695 1696 static struct rtnl_link_ops erspan_link_ops __read_mostly = { 1697 .kind = "erspan", 1698 .maxtype = IFLA_GRE_MAX, 1699 .policy = ipgre_policy, 1700 .priv_size = sizeof(struct ip_tunnel), 1701 .setup = erspan_setup, 1702 .validate = erspan_validate, 1703 .newlink = erspan_newlink, 1704 .changelink = erspan_changelink, 1705 .dellink = ip_tunnel_dellink, 1706 .get_size = ipgre_get_size, 1707 .fill_info = erspan_fill_info, 1708 .get_link_net = ip_tunnel_get_link_net, 1709 }; 1710 1711 struct net_device *gretap_fb_dev_create(struct net *net, const char *name, 1712 u8 name_assign_type) 1713 { 1714 struct rtnl_newlink_params params = { .src_net = net }; 1715 struct nlattr *tb[IFLA_MAX + 1]; 1716 struct net_device *dev; 1717 LIST_HEAD(list_kill); 1718 struct ip_tunnel *t; 1719 int err; 1720 1721 memset(&tb, 0, sizeof(tb)); 1722 params.tb = tb; 1723 1724 dev = rtnl_create_link(net, name, name_assign_type, 1725 &ipgre_tap_ops, tb, NULL); 1726 if (IS_ERR(dev)) 1727 return dev; 1728 1729 /* Configure flow based GRE device. */ 1730 t = netdev_priv(dev); 1731 t->collect_md = true; 1732 1733 err = ipgre_newlink(dev, ¶ms, NULL); 1734 if (err < 0) { 1735 free_netdev(dev); 1736 return ERR_PTR(err); 1737 } 1738 1739 /* openvswitch users expect packet sizes to be unrestricted, 1740 * so set the largest MTU we can. 1741 */ 1742 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); 1743 if (err) 1744 goto out; 1745 1746 err = rtnl_configure_link(dev, NULL, 0, NULL); 1747 if (err < 0) 1748 goto out; 1749 1750 return dev; 1751 out: 1752 ip_tunnel_dellink(dev, &list_kill); 1753 unregister_netdevice_many(&list_kill); 1754 return ERR_PTR(err); 1755 } 1756 EXPORT_SYMBOL_GPL(gretap_fb_dev_create); 1757 1758 static int __net_init ipgre_tap_init_net(struct net *net) 1759 { 1760 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); 1761 } 1762 1763 static void __net_exit ipgre_tap_exit_rtnl(struct net *net, 1764 struct list_head *dev_to_kill) 1765 { 1766 ip_tunnel_delete_net(net, gre_tap_net_id, &ipgre_tap_ops, dev_to_kill); 1767 } 1768 1769 static struct pernet_operations ipgre_tap_net_ops = { 1770 .init = ipgre_tap_init_net, 1771 .exit_rtnl = ipgre_tap_exit_rtnl, 1772 .id = &gre_tap_net_id, 1773 .size = sizeof(struct ip_tunnel_net), 1774 }; 1775 1776 static int __net_init erspan_init_net(struct net *net) 1777 { 1778 return ip_tunnel_init_net(net, erspan_net_id, 1779 &erspan_link_ops, "erspan0"); 1780 } 1781 1782 static void __net_exit erspan_exit_rtnl(struct net *net, 1783 struct list_head *dev_to_kill) 1784 { 1785 ip_tunnel_delete_net(net, erspan_net_id, &erspan_link_ops, dev_to_kill); 1786 } 1787 1788 static struct pernet_operations erspan_net_ops = { 1789 .init = erspan_init_net, 1790 .exit_rtnl = erspan_exit_rtnl, 1791 .id = &erspan_net_id, 1792 .size = sizeof(struct ip_tunnel_net), 1793 }; 1794 1795 static int __init ipgre_init(void) 1796 { 1797 int err; 1798 1799 pr_info("GRE over IPv4 tunneling driver\n"); 1800 1801 err = register_pernet_device(&ipgre_net_ops); 1802 if (err < 0) 1803 return err; 1804 1805 err = register_pernet_device(&ipgre_tap_net_ops); 1806 if (err < 0) 1807 goto pnet_tap_failed; 1808 1809 err = register_pernet_device(&erspan_net_ops); 1810 if (err < 0) 1811 goto pnet_erspan_failed; 1812 1813 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); 1814 if (err < 0) { 1815 pr_info("%s: can't add protocol\n", __func__); 1816 goto add_proto_failed; 1817 } 1818 1819 err = rtnl_link_register(&ipgre_link_ops); 1820 if (err < 0) 1821 goto rtnl_link_failed; 1822 1823 err = rtnl_link_register(&ipgre_tap_ops); 1824 if (err < 0) 1825 goto tap_ops_failed; 1826 1827 err = rtnl_link_register(&erspan_link_ops); 1828 if (err < 0) 1829 goto erspan_link_failed; 1830 1831 return 0; 1832 1833 erspan_link_failed: 1834 rtnl_link_unregister(&ipgre_tap_ops); 1835 tap_ops_failed: 1836 rtnl_link_unregister(&ipgre_link_ops); 1837 rtnl_link_failed: 1838 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1839 add_proto_failed: 1840 unregister_pernet_device(&erspan_net_ops); 1841 pnet_erspan_failed: 1842 unregister_pernet_device(&ipgre_tap_net_ops); 1843 pnet_tap_failed: 1844 unregister_pernet_device(&ipgre_net_ops); 1845 return err; 1846 } 1847 1848 static void __exit ipgre_fini(void) 1849 { 1850 rtnl_link_unregister(&ipgre_tap_ops); 1851 rtnl_link_unregister(&ipgre_link_ops); 1852 rtnl_link_unregister(&erspan_link_ops); 1853 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1854 unregister_pernet_device(&ipgre_tap_net_ops); 1855 unregister_pernet_device(&ipgre_net_ops); 1856 unregister_pernet_device(&erspan_net_ops); 1857 } 1858 1859 module_init(ipgre_init); 1860 module_exit(ipgre_fini); 1861 MODULE_DESCRIPTION("IPv4 GRE tunnels over IP library"); 1862 MODULE_LICENSE("GPL"); 1863 MODULE_ALIAS_RTNL_LINK("gre"); 1864 MODULE_ALIAS_RTNL_LINK("gretap"); 1865 MODULE_ALIAS_RTNL_LINK("erspan"); 1866 MODULE_ALIAS_NETDEV("gre0"); 1867 MODULE_ALIAS_NETDEV("gretap0"); 1868 MODULE_ALIAS_NETDEV("erspan0"); 1869