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_batch_rtnl(struct list_head *list_net, 1070 struct list_head *dev_to_kill) 1071 { 1072 ip_tunnel_delete_nets(list_net, ipgre_net_id, &ipgre_link_ops, 1073 dev_to_kill); 1074 } 1075 1076 static struct pernet_operations ipgre_net_ops = { 1077 .init = ipgre_init_net, 1078 .exit_batch_rtnl = ipgre_exit_batch_rtnl, 1079 .id = &ipgre_net_id, 1080 .size = sizeof(struct ip_tunnel_net), 1081 }; 1082 1083 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1084 struct netlink_ext_ack *extack) 1085 { 1086 __be16 flags; 1087 1088 if (!data) 1089 return 0; 1090 1091 flags = 0; 1092 if (data[IFLA_GRE_IFLAGS]) 1093 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1094 if (data[IFLA_GRE_OFLAGS]) 1095 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1096 if (flags & (GRE_VERSION|GRE_ROUTING)) 1097 return -EINVAL; 1098 1099 if (data[IFLA_GRE_COLLECT_METADATA] && 1100 data[IFLA_GRE_ENCAP_TYPE] && 1101 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) 1102 return -EINVAL; 1103 1104 return 0; 1105 } 1106 1107 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1108 struct netlink_ext_ack *extack) 1109 { 1110 __be32 daddr; 1111 1112 if (tb[IFLA_ADDRESS]) { 1113 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1114 return -EINVAL; 1115 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1116 return -EADDRNOTAVAIL; 1117 } 1118 1119 if (!data) 1120 goto out; 1121 1122 if (data[IFLA_GRE_REMOTE]) { 1123 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); 1124 if (!daddr) 1125 return -EINVAL; 1126 } 1127 1128 out: 1129 return ipgre_tunnel_validate(tb, data, extack); 1130 } 1131 1132 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], 1133 struct netlink_ext_ack *extack) 1134 { 1135 __be16 flags = 0; 1136 int ret; 1137 1138 if (!data) 1139 return 0; 1140 1141 ret = ipgre_tap_validate(tb, data, extack); 1142 if (ret) 1143 return ret; 1144 1145 if (data[IFLA_GRE_ERSPAN_VER] && 1146 nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) 1147 return 0; 1148 1149 /* ERSPAN type II/III should only have GRE sequence and key flag */ 1150 if (data[IFLA_GRE_OFLAGS]) 1151 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1152 if (data[IFLA_GRE_IFLAGS]) 1153 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1154 if (!data[IFLA_GRE_COLLECT_METADATA] && 1155 flags != (GRE_SEQ | GRE_KEY)) 1156 return -EINVAL; 1157 1158 /* ERSPAN Session ID only has 10-bit. Since we reuse 1159 * 32-bit key field as ID, check it's range. 1160 */ 1161 if (data[IFLA_GRE_IKEY] && 1162 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK)) 1163 return -EINVAL; 1164 1165 if (data[IFLA_GRE_OKEY] && 1166 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK)) 1167 return -EINVAL; 1168 1169 return 0; 1170 } 1171 1172 static int ipgre_netlink_parms(struct net_device *dev, 1173 struct nlattr *data[], 1174 struct nlattr *tb[], 1175 struct ip_tunnel_parm_kern *parms, 1176 __u32 *fwmark) 1177 { 1178 struct ip_tunnel *t = netdev_priv(dev); 1179 1180 memset(parms, 0, sizeof(*parms)); 1181 1182 parms->iph.protocol = IPPROTO_GRE; 1183 1184 if (!data) 1185 return 0; 1186 1187 if (data[IFLA_GRE_LINK]) 1188 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1189 1190 if (data[IFLA_GRE_IFLAGS]) 1191 gre_flags_to_tnl_flags(parms->i_flags, 1192 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1193 1194 if (data[IFLA_GRE_OFLAGS]) 1195 gre_flags_to_tnl_flags(parms->o_flags, 1196 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1197 1198 if (data[IFLA_GRE_IKEY]) 1199 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1200 1201 if (data[IFLA_GRE_OKEY]) 1202 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1203 1204 if (data[IFLA_GRE_LOCAL]) 1205 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); 1206 1207 if (data[IFLA_GRE_REMOTE]) 1208 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); 1209 1210 if (data[IFLA_GRE_TTL]) 1211 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); 1212 1213 if (data[IFLA_GRE_TOS]) 1214 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); 1215 1216 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) { 1217 if (t->ignore_df) 1218 return -EINVAL; 1219 parms->iph.frag_off = htons(IP_DF); 1220 } 1221 1222 if (data[IFLA_GRE_COLLECT_METADATA]) { 1223 t->collect_md = true; 1224 if (dev->type == ARPHRD_IPGRE) 1225 dev->type = ARPHRD_NONE; 1226 } 1227 1228 if (data[IFLA_GRE_IGNORE_DF]) { 1229 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF]) 1230 && (parms->iph.frag_off & htons(IP_DF))) 1231 return -EINVAL; 1232 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]); 1233 } 1234 1235 if (data[IFLA_GRE_FWMARK]) 1236 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1237 1238 return 0; 1239 } 1240 1241 static int erspan_netlink_parms(struct net_device *dev, 1242 struct nlattr *data[], 1243 struct nlattr *tb[], 1244 struct ip_tunnel_parm_kern *parms, 1245 __u32 *fwmark) 1246 { 1247 struct ip_tunnel *t = netdev_priv(dev); 1248 int err; 1249 1250 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark); 1251 if (err) 1252 return err; 1253 if (!data) 1254 return 0; 1255 1256 if (data[IFLA_GRE_ERSPAN_VER]) { 1257 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); 1258 1259 if (t->erspan_ver > 2) 1260 return -EINVAL; 1261 } 1262 1263 if (t->erspan_ver == 1) { 1264 if (data[IFLA_GRE_ERSPAN_INDEX]) { 1265 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]); 1266 if (t->index & ~INDEX_MASK) 1267 return -EINVAL; 1268 } 1269 } else if (t->erspan_ver == 2) { 1270 if (data[IFLA_GRE_ERSPAN_DIR]) { 1271 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]); 1272 if (t->dir & ~(DIR_MASK >> DIR_OFFSET)) 1273 return -EINVAL; 1274 } 1275 if (data[IFLA_GRE_ERSPAN_HWID]) { 1276 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]); 1277 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET)) 1278 return -EINVAL; 1279 } 1280 } 1281 1282 return 0; 1283 } 1284 1285 /* This function returns true when ENCAP attributes are present in the nl msg */ 1286 static bool ipgre_netlink_encap_parms(struct nlattr *data[], 1287 struct ip_tunnel_encap *ipencap) 1288 { 1289 bool ret = false; 1290 1291 memset(ipencap, 0, sizeof(*ipencap)); 1292 1293 if (!data) 1294 return ret; 1295 1296 if (data[IFLA_GRE_ENCAP_TYPE]) { 1297 ret = true; 1298 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1299 } 1300 1301 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1302 ret = true; 1303 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1304 } 1305 1306 if (data[IFLA_GRE_ENCAP_SPORT]) { 1307 ret = true; 1308 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1309 } 1310 1311 if (data[IFLA_GRE_ENCAP_DPORT]) { 1312 ret = true; 1313 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1314 } 1315 1316 return ret; 1317 } 1318 1319 static int gre_tap_init(struct net_device *dev) 1320 { 1321 __gre_tunnel_init(dev); 1322 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1323 netif_keep_dst(dev); 1324 1325 return ip_tunnel_init(dev); 1326 } 1327 1328 static const struct net_device_ops gre_tap_netdev_ops = { 1329 .ndo_init = gre_tap_init, 1330 .ndo_uninit = ip_tunnel_uninit, 1331 .ndo_start_xmit = gre_tap_xmit, 1332 .ndo_set_mac_address = eth_mac_addr, 1333 .ndo_validate_addr = eth_validate_addr, 1334 .ndo_change_mtu = ip_tunnel_change_mtu, 1335 .ndo_get_stats64 = dev_get_tstats64, 1336 .ndo_get_iflink = ip_tunnel_get_iflink, 1337 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1338 }; 1339 1340 static int erspan_tunnel_init(struct net_device *dev) 1341 { 1342 struct ip_tunnel *tunnel = netdev_priv(dev); 1343 1344 if (tunnel->erspan_ver == 0) 1345 tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ 1346 else 1347 tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ 1348 1349 tunnel->parms.iph.protocol = IPPROTO_GRE; 1350 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + 1351 erspan_hdr_len(tunnel->erspan_ver); 1352 1353 dev->features |= GRE_FEATURES; 1354 dev->hw_features |= GRE_FEATURES; 1355 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1356 netif_keep_dst(dev); 1357 1358 return ip_tunnel_init(dev); 1359 } 1360 1361 static const struct net_device_ops erspan_netdev_ops = { 1362 .ndo_init = erspan_tunnel_init, 1363 .ndo_uninit = ip_tunnel_uninit, 1364 .ndo_start_xmit = erspan_xmit, 1365 .ndo_set_mac_address = eth_mac_addr, 1366 .ndo_validate_addr = eth_validate_addr, 1367 .ndo_change_mtu = ip_tunnel_change_mtu, 1368 .ndo_get_stats64 = dev_get_tstats64, 1369 .ndo_get_iflink = ip_tunnel_get_iflink, 1370 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1371 }; 1372 1373 static void ipgre_tap_setup(struct net_device *dev) 1374 { 1375 ether_setup(dev); 1376 dev->max_mtu = 0; 1377 dev->netdev_ops = &gre_tap_netdev_ops; 1378 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1379 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1380 ip_tunnel_setup(dev, gre_tap_net_id); 1381 } 1382 1383 static int 1384 ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[]) 1385 { 1386 struct ip_tunnel_encap ipencap; 1387 1388 if (ipgre_netlink_encap_parms(data, &ipencap)) { 1389 struct ip_tunnel *t = netdev_priv(dev); 1390 int err = ip_tunnel_encap_setup(t, &ipencap); 1391 1392 if (err < 0) 1393 return err; 1394 } 1395 1396 return 0; 1397 } 1398 1399 static int ipgre_newlink(struct net *src_net, struct net_device *dev, 1400 struct nlattr *tb[], struct nlattr *data[], 1401 struct netlink_ext_ack *extack) 1402 { 1403 struct ip_tunnel_parm_kern p; 1404 __u32 fwmark = 0; 1405 int err; 1406 1407 err = ipgre_newlink_encap_setup(dev, data); 1408 if (err) 1409 return err; 1410 1411 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1412 if (err < 0) 1413 return err; 1414 return ip_tunnel_newlink(dev, tb, &p, fwmark); 1415 } 1416 1417 static int erspan_newlink(struct net *src_net, struct net_device *dev, 1418 struct nlattr *tb[], struct nlattr *data[], 1419 struct netlink_ext_ack *extack) 1420 { 1421 struct ip_tunnel_parm_kern p; 1422 __u32 fwmark = 0; 1423 int err; 1424 1425 err = ipgre_newlink_encap_setup(dev, data); 1426 if (err) 1427 return err; 1428 1429 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1430 if (err) 1431 return err; 1432 return ip_tunnel_newlink(dev, tb, &p, fwmark); 1433 } 1434 1435 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], 1436 struct nlattr *data[], 1437 struct netlink_ext_ack *extack) 1438 { 1439 struct ip_tunnel *t = netdev_priv(dev); 1440 struct ip_tunnel_parm_kern p; 1441 __u32 fwmark = t->fwmark; 1442 int err; 1443 1444 err = ipgre_newlink_encap_setup(dev, data); 1445 if (err) 1446 return err; 1447 1448 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1449 if (err < 0) 1450 return err; 1451 1452 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1453 if (err < 0) 1454 return err; 1455 1456 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1457 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1458 1459 ipgre_link_update(dev, !tb[IFLA_MTU]); 1460 1461 return 0; 1462 } 1463 1464 static int erspan_changelink(struct net_device *dev, struct nlattr *tb[], 1465 struct nlattr *data[], 1466 struct netlink_ext_ack *extack) 1467 { 1468 struct ip_tunnel *t = netdev_priv(dev); 1469 struct ip_tunnel_parm_kern p; 1470 __u32 fwmark = t->fwmark; 1471 int err; 1472 1473 err = ipgre_newlink_encap_setup(dev, data); 1474 if (err) 1475 return err; 1476 1477 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1478 if (err < 0) 1479 return err; 1480 1481 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1482 if (err < 0) 1483 return err; 1484 1485 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1486 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1487 1488 return 0; 1489 } 1490 1491 static size_t ipgre_get_size(const struct net_device *dev) 1492 { 1493 return 1494 /* IFLA_GRE_LINK */ 1495 nla_total_size(4) + 1496 /* IFLA_GRE_IFLAGS */ 1497 nla_total_size(2) + 1498 /* IFLA_GRE_OFLAGS */ 1499 nla_total_size(2) + 1500 /* IFLA_GRE_IKEY */ 1501 nla_total_size(4) + 1502 /* IFLA_GRE_OKEY */ 1503 nla_total_size(4) + 1504 /* IFLA_GRE_LOCAL */ 1505 nla_total_size(4) + 1506 /* IFLA_GRE_REMOTE */ 1507 nla_total_size(4) + 1508 /* IFLA_GRE_TTL */ 1509 nla_total_size(1) + 1510 /* IFLA_GRE_TOS */ 1511 nla_total_size(1) + 1512 /* IFLA_GRE_PMTUDISC */ 1513 nla_total_size(1) + 1514 /* IFLA_GRE_ENCAP_TYPE */ 1515 nla_total_size(2) + 1516 /* IFLA_GRE_ENCAP_FLAGS */ 1517 nla_total_size(2) + 1518 /* IFLA_GRE_ENCAP_SPORT */ 1519 nla_total_size(2) + 1520 /* IFLA_GRE_ENCAP_DPORT */ 1521 nla_total_size(2) + 1522 /* IFLA_GRE_COLLECT_METADATA */ 1523 nla_total_size(0) + 1524 /* IFLA_GRE_IGNORE_DF */ 1525 nla_total_size(1) + 1526 /* IFLA_GRE_FWMARK */ 1527 nla_total_size(4) + 1528 /* IFLA_GRE_ERSPAN_INDEX */ 1529 nla_total_size(4) + 1530 /* IFLA_GRE_ERSPAN_VER */ 1531 nla_total_size(1) + 1532 /* IFLA_GRE_ERSPAN_DIR */ 1533 nla_total_size(1) + 1534 /* IFLA_GRE_ERSPAN_HWID */ 1535 nla_total_size(2) + 1536 0; 1537 } 1538 1539 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1540 { 1541 struct ip_tunnel *t = netdev_priv(dev); 1542 struct ip_tunnel_parm_kern *p = &t->parms; 1543 IP_TUNNEL_DECLARE_FLAGS(o_flags); 1544 1545 ip_tunnel_flags_copy(o_flags, p->o_flags); 1546 1547 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1548 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1549 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1550 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1551 gre_tnl_flags_to_gre_flags(o_flags)) || 1552 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1553 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1554 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || 1555 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || 1556 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || 1557 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || 1558 nla_put_u8(skb, IFLA_GRE_PMTUDISC, 1559 !!(p->iph.frag_off & htons(IP_DF))) || 1560 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark)) 1561 goto nla_put_failure; 1562 1563 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1564 t->encap.type) || 1565 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1566 t->encap.sport) || 1567 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1568 t->encap.dport) || 1569 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1570 t->encap.flags)) 1571 goto nla_put_failure; 1572 1573 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df)) 1574 goto nla_put_failure; 1575 1576 if (t->collect_md) { 1577 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) 1578 goto nla_put_failure; 1579 } 1580 1581 return 0; 1582 1583 nla_put_failure: 1584 return -EMSGSIZE; 1585 } 1586 1587 static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev) 1588 { 1589 struct ip_tunnel *t = netdev_priv(dev); 1590 1591 if (t->erspan_ver <= 2) { 1592 if (t->erspan_ver != 0 && !t->collect_md) 1593 __set_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags); 1594 1595 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) 1596 goto nla_put_failure; 1597 1598 if (t->erspan_ver == 1) { 1599 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) 1600 goto nla_put_failure; 1601 } else if (t->erspan_ver == 2) { 1602 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) 1603 goto nla_put_failure; 1604 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid)) 1605 goto nla_put_failure; 1606 } 1607 } 1608 1609 return ipgre_fill_info(skb, dev); 1610 1611 nla_put_failure: 1612 return -EMSGSIZE; 1613 } 1614 1615 static void erspan_setup(struct net_device *dev) 1616 { 1617 struct ip_tunnel *t = netdev_priv(dev); 1618 1619 ether_setup(dev); 1620 dev->max_mtu = 0; 1621 dev->netdev_ops = &erspan_netdev_ops; 1622 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1623 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1624 ip_tunnel_setup(dev, erspan_net_id); 1625 t->erspan_ver = 1; 1626 } 1627 1628 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { 1629 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1630 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1631 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1632 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1633 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1634 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) }, 1635 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, 1636 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1637 [IFLA_GRE_TOS] = { .type = NLA_U8 }, 1638 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, 1639 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1640 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1641 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1642 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1643 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, 1644 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 }, 1645 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1646 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 }, 1647 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 }, 1648 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 }, 1649 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 }, 1650 }; 1651 1652 static struct rtnl_link_ops ipgre_link_ops __read_mostly = { 1653 .kind = "gre", 1654 .maxtype = IFLA_GRE_MAX, 1655 .policy = ipgre_policy, 1656 .priv_size = sizeof(struct ip_tunnel), 1657 .setup = ipgre_tunnel_setup, 1658 .validate = ipgre_tunnel_validate, 1659 .newlink = ipgre_newlink, 1660 .changelink = ipgre_changelink, 1661 .dellink = ip_tunnel_dellink, 1662 .get_size = ipgre_get_size, 1663 .fill_info = ipgre_fill_info, 1664 .get_link_net = ip_tunnel_get_link_net, 1665 }; 1666 1667 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { 1668 .kind = "gretap", 1669 .maxtype = IFLA_GRE_MAX, 1670 .policy = ipgre_policy, 1671 .priv_size = sizeof(struct ip_tunnel), 1672 .setup = ipgre_tap_setup, 1673 .validate = ipgre_tap_validate, 1674 .newlink = ipgre_newlink, 1675 .changelink = ipgre_changelink, 1676 .dellink = ip_tunnel_dellink, 1677 .get_size = ipgre_get_size, 1678 .fill_info = ipgre_fill_info, 1679 .get_link_net = ip_tunnel_get_link_net, 1680 }; 1681 1682 static struct rtnl_link_ops erspan_link_ops __read_mostly = { 1683 .kind = "erspan", 1684 .maxtype = IFLA_GRE_MAX, 1685 .policy = ipgre_policy, 1686 .priv_size = sizeof(struct ip_tunnel), 1687 .setup = erspan_setup, 1688 .validate = erspan_validate, 1689 .newlink = erspan_newlink, 1690 .changelink = erspan_changelink, 1691 .dellink = ip_tunnel_dellink, 1692 .get_size = ipgre_get_size, 1693 .fill_info = erspan_fill_info, 1694 .get_link_net = ip_tunnel_get_link_net, 1695 }; 1696 1697 struct net_device *gretap_fb_dev_create(struct net *net, const char *name, 1698 u8 name_assign_type) 1699 { 1700 struct nlattr *tb[IFLA_MAX + 1]; 1701 struct net_device *dev; 1702 LIST_HEAD(list_kill); 1703 struct ip_tunnel *t; 1704 int err; 1705 1706 memset(&tb, 0, sizeof(tb)); 1707 1708 dev = rtnl_create_link(net, name, name_assign_type, 1709 &ipgre_tap_ops, tb, NULL); 1710 if (IS_ERR(dev)) 1711 return dev; 1712 1713 /* Configure flow based GRE device. */ 1714 t = netdev_priv(dev); 1715 t->collect_md = true; 1716 1717 err = ipgre_newlink(net, dev, tb, NULL, NULL); 1718 if (err < 0) { 1719 free_netdev(dev); 1720 return ERR_PTR(err); 1721 } 1722 1723 /* openvswitch users expect packet sizes to be unrestricted, 1724 * so set the largest MTU we can. 1725 */ 1726 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); 1727 if (err) 1728 goto out; 1729 1730 err = rtnl_configure_link(dev, NULL, 0, NULL); 1731 if (err < 0) 1732 goto out; 1733 1734 return dev; 1735 out: 1736 ip_tunnel_dellink(dev, &list_kill); 1737 unregister_netdevice_many(&list_kill); 1738 return ERR_PTR(err); 1739 } 1740 EXPORT_SYMBOL_GPL(gretap_fb_dev_create); 1741 1742 static int __net_init ipgre_tap_init_net(struct net *net) 1743 { 1744 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); 1745 } 1746 1747 static void __net_exit ipgre_tap_exit_batch_rtnl(struct list_head *list_net, 1748 struct list_head *dev_to_kill) 1749 { 1750 ip_tunnel_delete_nets(list_net, gre_tap_net_id, &ipgre_tap_ops, 1751 dev_to_kill); 1752 } 1753 1754 static struct pernet_operations ipgre_tap_net_ops = { 1755 .init = ipgre_tap_init_net, 1756 .exit_batch_rtnl = ipgre_tap_exit_batch_rtnl, 1757 .id = &gre_tap_net_id, 1758 .size = sizeof(struct ip_tunnel_net), 1759 }; 1760 1761 static int __net_init erspan_init_net(struct net *net) 1762 { 1763 return ip_tunnel_init_net(net, erspan_net_id, 1764 &erspan_link_ops, "erspan0"); 1765 } 1766 1767 static void __net_exit erspan_exit_batch_rtnl(struct list_head *net_list, 1768 struct list_head *dev_to_kill) 1769 { 1770 ip_tunnel_delete_nets(net_list, erspan_net_id, &erspan_link_ops, 1771 dev_to_kill); 1772 } 1773 1774 static struct pernet_operations erspan_net_ops = { 1775 .init = erspan_init_net, 1776 .exit_batch_rtnl = erspan_exit_batch_rtnl, 1777 .id = &erspan_net_id, 1778 .size = sizeof(struct ip_tunnel_net), 1779 }; 1780 1781 static int __init ipgre_init(void) 1782 { 1783 int err; 1784 1785 pr_info("GRE over IPv4 tunneling driver\n"); 1786 1787 err = register_pernet_device(&ipgre_net_ops); 1788 if (err < 0) 1789 return err; 1790 1791 err = register_pernet_device(&ipgre_tap_net_ops); 1792 if (err < 0) 1793 goto pnet_tap_failed; 1794 1795 err = register_pernet_device(&erspan_net_ops); 1796 if (err < 0) 1797 goto pnet_erspan_failed; 1798 1799 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); 1800 if (err < 0) { 1801 pr_info("%s: can't add protocol\n", __func__); 1802 goto add_proto_failed; 1803 } 1804 1805 err = rtnl_link_register(&ipgre_link_ops); 1806 if (err < 0) 1807 goto rtnl_link_failed; 1808 1809 err = rtnl_link_register(&ipgre_tap_ops); 1810 if (err < 0) 1811 goto tap_ops_failed; 1812 1813 err = rtnl_link_register(&erspan_link_ops); 1814 if (err < 0) 1815 goto erspan_link_failed; 1816 1817 return 0; 1818 1819 erspan_link_failed: 1820 rtnl_link_unregister(&ipgre_tap_ops); 1821 tap_ops_failed: 1822 rtnl_link_unregister(&ipgre_link_ops); 1823 rtnl_link_failed: 1824 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1825 add_proto_failed: 1826 unregister_pernet_device(&erspan_net_ops); 1827 pnet_erspan_failed: 1828 unregister_pernet_device(&ipgre_tap_net_ops); 1829 pnet_tap_failed: 1830 unregister_pernet_device(&ipgre_net_ops); 1831 return err; 1832 } 1833 1834 static void __exit ipgre_fini(void) 1835 { 1836 rtnl_link_unregister(&ipgre_tap_ops); 1837 rtnl_link_unregister(&ipgre_link_ops); 1838 rtnl_link_unregister(&erspan_link_ops); 1839 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1840 unregister_pernet_device(&ipgre_tap_net_ops); 1841 unregister_pernet_device(&ipgre_net_ops); 1842 unregister_pernet_device(&erspan_net_ops); 1843 } 1844 1845 module_init(ipgre_init); 1846 module_exit(ipgre_fini); 1847 MODULE_DESCRIPTION("IPv4 GRE tunnels over IP library"); 1848 MODULE_LICENSE("GPL"); 1849 MODULE_ALIAS_RTNL_LINK("gre"); 1850 MODULE_ALIAS_RTNL_LINK("gretap"); 1851 MODULE_ALIAS_RTNL_LINK("erspan"); 1852 MODULE_ALIAS_NETDEV("gre0"); 1853 MODULE_ALIAS_NETDEV("gretap0"); 1854 MODULE_ALIAS_NETDEV("erspan0"); 1855