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, READ_ONCE(t->err_time) + IPTUNNEL_ERR_TIMEO)) 211 WRITE_ONCE(t->err_count, READ_ONCE(t->err_count) + 1); 212 else 213 WRITE_ONCE(t->err_count, 1); 214 WRITE_ONCE(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 dev_core_stats_rx_dropped_inc(skb->dev); 472 kfree_skb(skb); 473 return 0; 474 } 475 476 static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, 477 const struct iphdr *tnl_params, 478 __be16 proto) 479 { 480 struct ip_tunnel *tunnel = netdev_priv(dev); 481 IP_TUNNEL_DECLARE_FLAGS(flags); 482 483 ip_tunnel_flags_copy(flags, tunnel->parms.o_flags); 484 485 /* Push GRE header. */ 486 gre_build_header(skb, tunnel->tun_hlen, 487 flags, proto, tunnel->parms.o_key, 488 test_bit(IP_TUNNEL_SEQ_BIT, flags) ? 489 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); 490 491 ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol); 492 } 493 494 static int gre_handle_offloads(struct sk_buff *skb, bool csum) 495 { 496 return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); 497 } 498 499 static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev, 500 __be16 proto) 501 { 502 struct ip_tunnel *tunnel = netdev_priv(dev); 503 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 504 struct ip_tunnel_info *tun_info; 505 const struct ip_tunnel_key *key; 506 int tunnel_hlen; 507 508 tun_info = skb_tunnel_info(skb); 509 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 510 ip_tunnel_info_af(tun_info) != AF_INET)) 511 goto err_free_skb; 512 513 key = &tun_info->key; 514 tunnel_hlen = gre_calc_hlen(key->tun_flags); 515 516 if (skb_cow_head(skb, dev->needed_headroom)) 517 goto err_free_skb; 518 519 /* Push Tunnel header. */ 520 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 521 tunnel->parms.o_flags))) 522 goto err_free_skb; 523 524 __set_bit(IP_TUNNEL_CSUM_BIT, flags); 525 __set_bit(IP_TUNNEL_KEY_BIT, flags); 526 __set_bit(IP_TUNNEL_SEQ_BIT, flags); 527 ip_tunnel_flags_and(flags, tun_info->key.tun_flags, flags); 528 529 gre_build_header(skb, tunnel_hlen, flags, proto, 530 tunnel_id_to_key32(tun_info->key.tun_id), 531 test_bit(IP_TUNNEL_SEQ_BIT, flags) ? 532 htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); 533 534 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); 535 536 return; 537 538 err_free_skb: 539 kfree_skb(skb); 540 DEV_STATS_INC(dev, tx_dropped); 541 } 542 543 static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev) 544 { 545 struct ip_tunnel *tunnel = netdev_priv(dev); 546 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 547 struct ip_tunnel_info *tun_info; 548 const struct ip_tunnel_key *key; 549 struct erspan_metadata *md; 550 bool truncate = false; 551 __be16 proto; 552 int tunnel_hlen; 553 int version; 554 int nhoff; 555 556 tun_info = skb_tunnel_info(skb); 557 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || 558 ip_tunnel_info_af(tun_info) != AF_INET)) 559 goto err_free_skb; 560 561 key = &tun_info->key; 562 if (!test_bit(IP_TUNNEL_ERSPAN_OPT_BIT, tun_info->key.tun_flags)) 563 goto err_free_skb; 564 if (tun_info->options_len < sizeof(*md)) 565 goto err_free_skb; 566 md = ip_tunnel_info_opts(tun_info); 567 568 /* ERSPAN has fixed 8 byte GRE header */ 569 version = md->version; 570 tunnel_hlen = 8 + erspan_hdr_len(version); 571 572 if (skb_cow_head(skb, dev->needed_headroom)) 573 goto err_free_skb; 574 575 if (gre_handle_offloads(skb, false)) 576 goto err_free_skb; 577 578 if (skb->len > dev->mtu + dev->hard_header_len) { 579 if (pskb_trim(skb, dev->mtu + dev->hard_header_len)) 580 goto err_free_skb; 581 truncate = true; 582 } 583 584 nhoff = skb_network_offset(skb); 585 if (skb->protocol == htons(ETH_P_IP) && 586 (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff)) 587 truncate = true; 588 589 if (skb->protocol == htons(ETH_P_IPV6)) { 590 int thoff; 591 592 if (skb_transport_header_was_set(skb)) 593 thoff = skb_transport_offset(skb); 594 else 595 thoff = nhoff + sizeof(struct ipv6hdr); 596 if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff) 597 truncate = true; 598 } 599 600 if (version == 1) { 601 erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)), 602 ntohl(md->u.index), truncate, true); 603 proto = htons(ETH_P_ERSPAN); 604 } else if (version == 2) { 605 erspan_build_header_v2(skb, 606 ntohl(tunnel_id_to_key32(key->tun_id)), 607 md->u.md2.dir, 608 get_hwid(&md->u.md2), 609 truncate, true); 610 proto = htons(ETH_P_ERSPAN2); 611 } else { 612 goto err_free_skb; 613 } 614 615 __set_bit(IP_TUNNEL_SEQ_BIT, flags); 616 gre_build_header(skb, 8, flags, proto, 0, 617 htonl(atomic_fetch_inc(&tunnel->o_seqno))); 618 619 ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); 620 621 return; 622 623 err_free_skb: 624 kfree_skb(skb); 625 DEV_STATS_INC(dev, tx_dropped); 626 } 627 628 static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 629 { 630 struct ip_tunnel_info *info = skb_tunnel_info(skb); 631 const struct ip_tunnel_key *key; 632 struct rtable *rt; 633 struct flowi4 fl4; 634 635 if (ip_tunnel_info_af(info) != AF_INET) 636 return -EINVAL; 637 638 key = &info->key; 639 ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src, 640 tunnel_id_to_key32(key->tun_id), 641 key->tos & ~INET_ECN_MASK, dev_net(dev), 0, 642 skb->mark, skb_get_hash(skb), key->flow_flags); 643 rt = ip_route_output_key(dev_net(dev), &fl4); 644 if (IS_ERR(rt)) 645 return PTR_ERR(rt); 646 647 ip_rt_put(rt); 648 info->key.u.ipv4.src = fl4.saddr; 649 return 0; 650 } 651 652 static netdev_tx_t ipgre_xmit(struct sk_buff *skb, 653 struct net_device *dev) 654 { 655 struct ip_tunnel *tunnel = netdev_priv(dev); 656 const struct iphdr *tnl_params; 657 658 if (!pskb_inet_may_pull(skb)) 659 goto free_skb; 660 661 if (tunnel->collect_md) { 662 gre_fb_xmit(skb, dev, skb->protocol); 663 return NETDEV_TX_OK; 664 } 665 666 if (dev->header_ops) { 667 int pull_len = tunnel->hlen + sizeof(struct iphdr); 668 669 if (skb_cow_head(skb, 0)) 670 goto free_skb; 671 672 if (!pskb_may_pull(skb, pull_len)) 673 goto free_skb; 674 675 tnl_params = (const struct iphdr *)skb->data; 676 677 /* ip_tunnel_xmit() needs skb->data pointing to gre header. */ 678 skb_pull(skb, pull_len); 679 skb_reset_mac_header(skb); 680 681 if (skb->ip_summed == CHECKSUM_PARTIAL && 682 skb_checksum_start(skb) < skb->data) 683 goto free_skb; 684 } else { 685 if (skb_cow_head(skb, dev->needed_headroom)) 686 goto free_skb; 687 688 tnl_params = &tunnel->parms.iph; 689 } 690 691 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 692 tunnel->parms.o_flags))) 693 goto free_skb; 694 695 __gre_xmit(skb, dev, tnl_params, skb->protocol); 696 return NETDEV_TX_OK; 697 698 free_skb: 699 kfree_skb(skb); 700 DEV_STATS_INC(dev, tx_dropped); 701 return NETDEV_TX_OK; 702 } 703 704 static netdev_tx_t erspan_xmit(struct sk_buff *skb, 705 struct net_device *dev) 706 { 707 struct ip_tunnel *tunnel = netdev_priv(dev); 708 bool truncate = false; 709 __be16 proto; 710 711 if (!pskb_inet_may_pull(skb)) 712 goto free_skb; 713 714 if (tunnel->collect_md) { 715 erspan_fb_xmit(skb, dev); 716 return NETDEV_TX_OK; 717 } 718 719 if (gre_handle_offloads(skb, false)) 720 goto free_skb; 721 722 if (skb_cow_head(skb, dev->needed_headroom)) 723 goto free_skb; 724 725 if (skb->len > dev->mtu + dev->hard_header_len) { 726 if (pskb_trim(skb, dev->mtu + dev->hard_header_len)) 727 goto free_skb; 728 truncate = true; 729 } 730 731 /* Push ERSPAN header */ 732 if (tunnel->erspan_ver == 0) { 733 proto = htons(ETH_P_ERSPAN); 734 __clear_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags); 735 } else if (tunnel->erspan_ver == 1) { 736 erspan_build_header(skb, ntohl(tunnel->parms.o_key), 737 tunnel->index, 738 truncate, true); 739 proto = htons(ETH_P_ERSPAN); 740 } else if (tunnel->erspan_ver == 2) { 741 erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key), 742 tunnel->dir, tunnel->hwid, 743 truncate, true); 744 proto = htons(ETH_P_ERSPAN2); 745 } else { 746 goto free_skb; 747 } 748 749 __clear_bit(IP_TUNNEL_KEY_BIT, tunnel->parms.o_flags); 750 __gre_xmit(skb, dev, &tunnel->parms.iph, proto); 751 return NETDEV_TX_OK; 752 753 free_skb: 754 kfree_skb(skb); 755 DEV_STATS_INC(dev, tx_dropped); 756 return NETDEV_TX_OK; 757 } 758 759 static netdev_tx_t gre_tap_xmit(struct sk_buff *skb, 760 struct net_device *dev) 761 { 762 struct ip_tunnel *tunnel = netdev_priv(dev); 763 764 if (!pskb_inet_may_pull(skb)) 765 goto free_skb; 766 767 if (tunnel->collect_md) { 768 gre_fb_xmit(skb, dev, htons(ETH_P_TEB)); 769 return NETDEV_TX_OK; 770 } 771 772 if (gre_handle_offloads(skb, test_bit(IP_TUNNEL_CSUM_BIT, 773 tunnel->parms.o_flags))) 774 goto free_skb; 775 776 if (skb_cow_head(skb, dev->needed_headroom)) 777 goto free_skb; 778 779 __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB)); 780 return NETDEV_TX_OK; 781 782 free_skb: 783 kfree_skb(skb); 784 DEV_STATS_INC(dev, tx_dropped); 785 return NETDEV_TX_OK; 786 } 787 788 static void ipgre_link_update(struct net_device *dev, bool set_mtu) 789 { 790 struct ip_tunnel *tunnel = netdev_priv(dev); 791 int len; 792 793 len = tunnel->tun_hlen; 794 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 795 len = tunnel->tun_hlen - len; 796 tunnel->hlen = tunnel->hlen + len; 797 798 if (dev->header_ops) 799 dev->hard_header_len += len; 800 else 801 dev->needed_headroom += len; 802 803 if (set_mtu) 804 WRITE_ONCE(dev->mtu, max_t(int, dev->mtu - len, 68)); 805 806 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags) || 807 (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) && 808 tunnel->encap.type != TUNNEL_ENCAP_NONE)) { 809 dev->features &= ~NETIF_F_GSO_SOFTWARE; 810 dev->hw_features &= ~NETIF_F_GSO_SOFTWARE; 811 } else { 812 dev->features |= NETIF_F_GSO_SOFTWARE; 813 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 814 } 815 } 816 817 static int ipgre_tunnel_ctl(struct net_device *dev, 818 struct ip_tunnel_parm_kern *p, 819 int cmd) 820 { 821 __be16 i_flags, o_flags; 822 int err; 823 824 if (!ip_tunnel_flags_is_be16_compat(p->i_flags) || 825 !ip_tunnel_flags_is_be16_compat(p->o_flags)) 826 return -EOVERFLOW; 827 828 i_flags = ip_tunnel_flags_to_be16(p->i_flags); 829 o_flags = ip_tunnel_flags_to_be16(p->o_flags); 830 831 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { 832 if (p->iph.version != 4 || p->iph.protocol != IPPROTO_GRE || 833 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)) || 834 ((i_flags | o_flags) & (GRE_VERSION | GRE_ROUTING))) 835 return -EINVAL; 836 } 837 838 gre_flags_to_tnl_flags(p->i_flags, i_flags); 839 gre_flags_to_tnl_flags(p->o_flags, o_flags); 840 841 err = ip_tunnel_ctl(dev, p, cmd); 842 if (err) 843 return err; 844 845 if (cmd == SIOCCHGTUNNEL) { 846 struct ip_tunnel *t = netdev_priv(dev); 847 848 ip_tunnel_flags_copy(t->parms.i_flags, p->i_flags); 849 ip_tunnel_flags_copy(t->parms.o_flags, p->o_flags); 850 851 if (strcmp(dev->rtnl_link_ops->kind, "erspan")) 852 ipgre_link_update(dev, true); 853 } 854 855 i_flags = gre_tnl_flags_to_gre_flags(p->i_flags); 856 ip_tunnel_flags_from_be16(p->i_flags, i_flags); 857 o_flags = gre_tnl_flags_to_gre_flags(p->o_flags); 858 ip_tunnel_flags_from_be16(p->o_flags, o_flags); 859 860 return 0; 861 } 862 863 /* Nice toy. Unfortunately, useless in real life :-) 864 It allows to construct virtual multiprotocol broadcast "LAN" 865 over the Internet, provided multicast routing is tuned. 866 867 868 I have no idea was this bicycle invented before me, 869 so that I had to set ARPHRD_IPGRE to a random value. 870 I have an impression, that Cisco could make something similar, 871 but this feature is apparently missing in IOS<=11.2(8). 872 873 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks 874 with broadcast 224.66.66.66. If you have access to mbone, play with me :-) 875 876 ping -t 255 224.66.66.66 877 878 If nobody answers, mbone does not work. 879 880 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255 881 ip addr add 10.66.66.<somewhat>/24 dev Universe 882 ifconfig Universe up 883 ifconfig Universe add fe80::<Your_real_addr>/10 884 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96 885 ftp 10.66.66.66 886 ... 887 ftp fec0:6666:6666::193.233.7.65 888 ... 889 */ 890 static int ipgre_header(struct sk_buff *skb, struct net_device *dev, 891 unsigned short type, 892 const void *daddr, const void *saddr, unsigned int len) 893 { 894 struct ip_tunnel *t = netdev_priv(dev); 895 struct gre_base_hdr *greh; 896 struct iphdr *iph; 897 int needed; 898 899 needed = t->hlen + sizeof(*iph); 900 if (skb_headroom(skb) < needed && 901 pskb_expand_head(skb, HH_DATA_ALIGN(needed - skb_headroom(skb)), 902 0, GFP_ATOMIC)) 903 return -needed; 904 905 iph = skb_push(skb, needed); 906 greh = (struct gre_base_hdr *)(iph+1); 907 greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags); 908 greh->protocol = htons(type); 909 910 memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); 911 912 /* Set the source hardware address. */ 913 if (saddr) 914 memcpy(&iph->saddr, saddr, 4); 915 if (daddr) 916 memcpy(&iph->daddr, daddr, 4); 917 if (iph->daddr) 918 return t->hlen + sizeof(*iph); 919 920 return -(t->hlen + sizeof(*iph)); 921 } 922 923 static int ipgre_header_parse(const struct sk_buff *skb, const struct net_device *dev, 924 unsigned char *haddr) 925 { 926 const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); 927 memcpy(haddr, &iph->saddr, 4); 928 return 4; 929 } 930 931 static const struct header_ops ipgre_header_ops = { 932 .create = ipgre_header, 933 .parse = ipgre_header_parse, 934 }; 935 936 #ifdef CONFIG_NET_IPGRE_BROADCAST 937 static int ipgre_open(struct net_device *dev) 938 { 939 struct ip_tunnel *t = netdev_priv(dev); 940 941 if (ipv4_is_multicast(t->parms.iph.daddr)) { 942 struct flowi4 fl4 = { 943 .flowi4_oif = t->parms.link, 944 .flowi4_dscp = ip4h_dscp(&t->parms.iph), 945 .flowi4_scope = RT_SCOPE_UNIVERSE, 946 .flowi4_proto = IPPROTO_GRE, 947 .saddr = t->parms.iph.saddr, 948 .daddr = t->parms.iph.daddr, 949 .fl4_gre_key = t->parms.o_key, 950 }; 951 struct rtable *rt; 952 953 rt = ip_route_output_key(t->net, &fl4); 954 if (IS_ERR(rt)) 955 return -EADDRNOTAVAIL; 956 dev = rt->dst.dev; 957 ip_rt_put(rt); 958 if (!__in_dev_get_rtnl(dev)) 959 return -EADDRNOTAVAIL; 960 t->mlink = dev->ifindex; 961 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); 962 } 963 return 0; 964 } 965 966 static int ipgre_close(struct net_device *dev) 967 { 968 struct ip_tunnel *t = netdev_priv(dev); 969 970 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { 971 struct in_device *in_dev; 972 in_dev = inetdev_by_index(t->net, t->mlink); 973 if (in_dev) 974 ip_mc_dec_group(in_dev, t->parms.iph.daddr); 975 } 976 return 0; 977 } 978 #endif 979 980 static const struct net_device_ops ipgre_netdev_ops = { 981 .ndo_init = ipgre_tunnel_init, 982 .ndo_uninit = ip_tunnel_uninit, 983 #ifdef CONFIG_NET_IPGRE_BROADCAST 984 .ndo_open = ipgre_open, 985 .ndo_stop = ipgre_close, 986 #endif 987 .ndo_start_xmit = ipgre_xmit, 988 .ndo_siocdevprivate = ip_tunnel_siocdevprivate, 989 .ndo_change_mtu = ip_tunnel_change_mtu, 990 .ndo_get_stats64 = dev_get_tstats64, 991 .ndo_get_iflink = ip_tunnel_get_iflink, 992 .ndo_tunnel_ctl = ipgre_tunnel_ctl, 993 }; 994 995 #define GRE_FEATURES (NETIF_F_SG | \ 996 NETIF_F_FRAGLIST | \ 997 NETIF_F_HIGHDMA | \ 998 NETIF_F_HW_CSUM) 999 1000 static void ipgre_tunnel_setup(struct net_device *dev) 1001 { 1002 dev->netdev_ops = &ipgre_netdev_ops; 1003 dev->type = ARPHRD_IPGRE; 1004 ip_tunnel_setup(dev, ipgre_net_id); 1005 } 1006 1007 static void __gre_tunnel_init(struct net_device *dev) 1008 { 1009 struct ip_tunnel *tunnel; 1010 1011 tunnel = netdev_priv(dev); 1012 tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); 1013 tunnel->parms.iph.protocol = IPPROTO_GRE; 1014 1015 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 1016 dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph); 1017 1018 dev->features |= GRE_FEATURES; 1019 dev->hw_features |= GRE_FEATURES; 1020 1021 /* TCP offload with GRE SEQ is not supported, nor can we support 2 1022 * levels of outer headers requiring an update. 1023 */ 1024 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.o_flags)) 1025 return; 1026 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.o_flags) && 1027 tunnel->encap.type != TUNNEL_ENCAP_NONE) 1028 return; 1029 1030 dev->features |= NETIF_F_GSO_SOFTWARE; 1031 dev->hw_features |= NETIF_F_GSO_SOFTWARE; 1032 1033 dev->lltx = true; 1034 } 1035 1036 static int ipgre_tunnel_init(struct net_device *dev) 1037 { 1038 struct ip_tunnel *tunnel = netdev_priv(dev); 1039 struct iphdr *iph = &tunnel->parms.iph; 1040 1041 __gre_tunnel_init(dev); 1042 1043 __dev_addr_set(dev, &iph->saddr, 4); 1044 memcpy(dev->broadcast, &iph->daddr, 4); 1045 1046 dev->flags = IFF_NOARP; 1047 netif_keep_dst(dev); 1048 dev->addr_len = 4; 1049 1050 if (iph->daddr && !tunnel->collect_md) { 1051 #ifdef CONFIG_NET_IPGRE_BROADCAST 1052 if (ipv4_is_multicast(iph->daddr)) { 1053 if (!iph->saddr) 1054 return -EINVAL; 1055 dev->flags = IFF_BROADCAST; 1056 dev->header_ops = &ipgre_header_ops; 1057 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1058 dev->needed_headroom = 0; 1059 } 1060 #endif 1061 } else if (!tunnel->collect_md) { 1062 dev->header_ops = &ipgre_header_ops; 1063 dev->hard_header_len = tunnel->hlen + sizeof(*iph); 1064 dev->needed_headroom = 0; 1065 } 1066 1067 return ip_tunnel_init(dev); 1068 } 1069 1070 static const struct gre_protocol ipgre_protocol = { 1071 .handler = gre_rcv, 1072 .err_handler = gre_err, 1073 }; 1074 1075 static int __net_init ipgre_init_net(struct net *net) 1076 { 1077 return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); 1078 } 1079 1080 static void __net_exit ipgre_exit_rtnl(struct net *net, 1081 struct list_head *dev_to_kill) 1082 { 1083 ip_tunnel_delete_net(net, ipgre_net_id, &ipgre_link_ops, dev_to_kill); 1084 } 1085 1086 static struct pernet_operations ipgre_net_ops = { 1087 .init = ipgre_init_net, 1088 .exit_rtnl = ipgre_exit_rtnl, 1089 .id = &ipgre_net_id, 1090 .size = sizeof(struct ip_tunnel_net), 1091 }; 1092 1093 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 1094 struct netlink_ext_ack *extack) 1095 { 1096 __be16 flags; 1097 1098 if (!data) 1099 return 0; 1100 1101 flags = 0; 1102 if (data[IFLA_GRE_IFLAGS]) 1103 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1104 if (data[IFLA_GRE_OFLAGS]) 1105 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1106 if (flags & (GRE_VERSION|GRE_ROUTING)) 1107 return -EINVAL; 1108 1109 if (data[IFLA_GRE_COLLECT_METADATA] && 1110 data[IFLA_GRE_ENCAP_TYPE] && 1111 nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) 1112 return -EINVAL; 1113 1114 return 0; 1115 } 1116 1117 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[], 1118 struct netlink_ext_ack *extack) 1119 { 1120 __be32 daddr; 1121 1122 if (tb[IFLA_ADDRESS]) { 1123 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 1124 return -EINVAL; 1125 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 1126 return -EADDRNOTAVAIL; 1127 } 1128 1129 if (!data) 1130 goto out; 1131 1132 if (data[IFLA_GRE_REMOTE]) { 1133 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); 1134 if (!daddr) 1135 return -EINVAL; 1136 } 1137 1138 out: 1139 return ipgre_tunnel_validate(tb, data, extack); 1140 } 1141 1142 static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], 1143 struct netlink_ext_ack *extack) 1144 { 1145 __be16 flags = 0; 1146 int ret; 1147 1148 if (!data) 1149 return 0; 1150 1151 ret = ipgre_tap_validate(tb, data, extack); 1152 if (ret) 1153 return ret; 1154 1155 if (data[IFLA_GRE_ERSPAN_VER] && 1156 nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) 1157 return 0; 1158 1159 /* ERSPAN type II/III should only have GRE sequence and key flag */ 1160 if (data[IFLA_GRE_OFLAGS]) 1161 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); 1162 if (data[IFLA_GRE_IFLAGS]) 1163 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); 1164 if (!data[IFLA_GRE_COLLECT_METADATA] && 1165 flags != (GRE_SEQ | GRE_KEY)) 1166 return -EINVAL; 1167 1168 /* ERSPAN Session ID only has 10-bit. Since we reuse 1169 * 32-bit key field as ID, check it's range. 1170 */ 1171 if (data[IFLA_GRE_IKEY] && 1172 (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK)) 1173 return -EINVAL; 1174 1175 if (data[IFLA_GRE_OKEY] && 1176 (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK)) 1177 return -EINVAL; 1178 1179 return 0; 1180 } 1181 1182 static int ipgre_netlink_parms(struct net_device *dev, 1183 struct nlattr *data[], 1184 struct nlattr *tb[], 1185 struct ip_tunnel_parm_kern *parms, 1186 __u32 *fwmark) 1187 { 1188 struct ip_tunnel *t = netdev_priv(dev); 1189 1190 memset(parms, 0, sizeof(*parms)); 1191 1192 parms->iph.protocol = IPPROTO_GRE; 1193 1194 if (!data) 1195 return 0; 1196 1197 if (data[IFLA_GRE_LINK]) 1198 parms->link = nla_get_u32(data[IFLA_GRE_LINK]); 1199 1200 if (data[IFLA_GRE_IFLAGS]) 1201 gre_flags_to_tnl_flags(parms->i_flags, 1202 nla_get_be16(data[IFLA_GRE_IFLAGS])); 1203 1204 if (data[IFLA_GRE_OFLAGS]) 1205 gre_flags_to_tnl_flags(parms->o_flags, 1206 nla_get_be16(data[IFLA_GRE_OFLAGS])); 1207 1208 if (data[IFLA_GRE_IKEY]) 1209 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); 1210 1211 if (data[IFLA_GRE_OKEY]) 1212 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); 1213 1214 if (data[IFLA_GRE_LOCAL]) 1215 parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); 1216 1217 if (data[IFLA_GRE_REMOTE]) 1218 parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); 1219 1220 if (data[IFLA_GRE_TTL]) 1221 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); 1222 1223 if (data[IFLA_GRE_TOS]) 1224 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); 1225 1226 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) { 1227 if (t->ignore_df) 1228 return -EINVAL; 1229 parms->iph.frag_off = htons(IP_DF); 1230 } 1231 1232 if (data[IFLA_GRE_COLLECT_METADATA]) { 1233 t->collect_md = true; 1234 if (dev->type == ARPHRD_IPGRE) 1235 dev->type = ARPHRD_NONE; 1236 } 1237 1238 if (data[IFLA_GRE_IGNORE_DF]) { 1239 if (nla_get_u8(data[IFLA_GRE_IGNORE_DF]) 1240 && (parms->iph.frag_off & htons(IP_DF))) 1241 return -EINVAL; 1242 t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]); 1243 } 1244 1245 if (data[IFLA_GRE_FWMARK]) 1246 *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); 1247 1248 return 0; 1249 } 1250 1251 static int erspan_netlink_parms(struct net_device *dev, 1252 struct nlattr *data[], 1253 struct nlattr *tb[], 1254 struct ip_tunnel_parm_kern *parms, 1255 __u32 *fwmark) 1256 { 1257 struct ip_tunnel *t = netdev_priv(dev); 1258 int err; 1259 1260 err = ipgre_netlink_parms(dev, data, tb, parms, fwmark); 1261 if (err) 1262 return err; 1263 if (!data) 1264 return 0; 1265 1266 if (data[IFLA_GRE_ERSPAN_VER]) { 1267 t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); 1268 1269 if (t->erspan_ver > 2) 1270 return -EINVAL; 1271 } 1272 1273 if (t->erspan_ver == 1) { 1274 if (data[IFLA_GRE_ERSPAN_INDEX]) { 1275 t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]); 1276 if (t->index & ~INDEX_MASK) 1277 return -EINVAL; 1278 } 1279 } else if (t->erspan_ver == 2) { 1280 if (data[IFLA_GRE_ERSPAN_DIR]) { 1281 t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]); 1282 if (t->dir & ~(DIR_MASK >> DIR_OFFSET)) 1283 return -EINVAL; 1284 } 1285 if (data[IFLA_GRE_ERSPAN_HWID]) { 1286 t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]); 1287 if (t->hwid & ~(HWID_MASK >> HWID_OFFSET)) 1288 return -EINVAL; 1289 } 1290 } 1291 1292 return 0; 1293 } 1294 1295 /* This function returns true when ENCAP attributes are present in the nl msg */ 1296 static bool ipgre_netlink_encap_parms(struct nlattr *data[], 1297 struct ip_tunnel_encap *ipencap) 1298 { 1299 bool ret = false; 1300 1301 memset(ipencap, 0, sizeof(*ipencap)); 1302 1303 if (!data) 1304 return ret; 1305 1306 if (data[IFLA_GRE_ENCAP_TYPE]) { 1307 ret = true; 1308 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); 1309 } 1310 1311 if (data[IFLA_GRE_ENCAP_FLAGS]) { 1312 ret = true; 1313 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); 1314 } 1315 1316 if (data[IFLA_GRE_ENCAP_SPORT]) { 1317 ret = true; 1318 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); 1319 } 1320 1321 if (data[IFLA_GRE_ENCAP_DPORT]) { 1322 ret = true; 1323 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); 1324 } 1325 1326 return ret; 1327 } 1328 1329 static int gre_tap_init(struct net_device *dev) 1330 { 1331 __gre_tunnel_init(dev); 1332 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1333 netif_keep_dst(dev); 1334 1335 return ip_tunnel_init(dev); 1336 } 1337 1338 static const struct net_device_ops gre_tap_netdev_ops = { 1339 .ndo_init = gre_tap_init, 1340 .ndo_uninit = ip_tunnel_uninit, 1341 .ndo_start_xmit = gre_tap_xmit, 1342 .ndo_set_mac_address = eth_mac_addr, 1343 .ndo_validate_addr = eth_validate_addr, 1344 .ndo_change_mtu = ip_tunnel_change_mtu, 1345 .ndo_get_stats64 = dev_get_tstats64, 1346 .ndo_get_iflink = ip_tunnel_get_iflink, 1347 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1348 }; 1349 1350 static int erspan_tunnel_init(struct net_device *dev) 1351 { 1352 struct ip_tunnel *tunnel = netdev_priv(dev); 1353 1354 if (tunnel->erspan_ver == 0) 1355 tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ 1356 else 1357 tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ 1358 1359 tunnel->parms.iph.protocol = IPPROTO_GRE; 1360 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + 1361 erspan_hdr_len(tunnel->erspan_ver); 1362 1363 dev->features |= GRE_FEATURES; 1364 dev->hw_features |= GRE_FEATURES; 1365 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1366 netif_keep_dst(dev); 1367 1368 return ip_tunnel_init(dev); 1369 } 1370 1371 static const struct net_device_ops erspan_netdev_ops = { 1372 .ndo_init = erspan_tunnel_init, 1373 .ndo_uninit = ip_tunnel_uninit, 1374 .ndo_start_xmit = erspan_xmit, 1375 .ndo_set_mac_address = eth_mac_addr, 1376 .ndo_validate_addr = eth_validate_addr, 1377 .ndo_change_mtu = ip_tunnel_change_mtu, 1378 .ndo_get_stats64 = dev_get_tstats64, 1379 .ndo_get_iflink = ip_tunnel_get_iflink, 1380 .ndo_fill_metadata_dst = gre_fill_metadata_dst, 1381 }; 1382 1383 static void ipgre_tap_setup(struct net_device *dev) 1384 { 1385 ether_setup(dev); 1386 dev->max_mtu = 0; 1387 dev->netdev_ops = &gre_tap_netdev_ops; 1388 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1389 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1390 ip_tunnel_setup(dev, gre_tap_net_id); 1391 } 1392 1393 static int 1394 ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[]) 1395 { 1396 struct ip_tunnel_encap ipencap; 1397 1398 if (ipgre_netlink_encap_parms(data, &ipencap)) { 1399 struct ip_tunnel *t = netdev_priv(dev); 1400 int err = ip_tunnel_encap_setup(t, &ipencap); 1401 1402 if (err < 0) 1403 return err; 1404 } 1405 1406 return 0; 1407 } 1408 1409 static int ipgre_newlink(struct net_device *dev, 1410 struct rtnl_newlink_params *params, 1411 struct netlink_ext_ack *extack) 1412 { 1413 struct nlattr **data = params->data; 1414 struct nlattr **tb = params->tb; 1415 struct ip_tunnel_parm_kern p; 1416 __u32 fwmark = 0; 1417 int err; 1418 1419 err = ipgre_newlink_encap_setup(dev, data); 1420 if (err) 1421 return err; 1422 1423 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1424 if (err < 0) 1425 return err; 1426 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1427 fwmark); 1428 } 1429 1430 static int erspan_newlink(struct net_device *dev, 1431 struct rtnl_newlink_params *params, 1432 struct netlink_ext_ack *extack) 1433 { 1434 struct nlattr **data = params->data; 1435 struct nlattr **tb = params->tb; 1436 struct ip_tunnel_parm_kern p; 1437 __u32 fwmark = 0; 1438 int err; 1439 1440 err = ipgre_newlink_encap_setup(dev, data); 1441 if (err) 1442 return err; 1443 1444 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1445 if (err) 1446 return err; 1447 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 1448 fwmark); 1449 } 1450 1451 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], 1452 struct nlattr *data[], 1453 struct netlink_ext_ack *extack) 1454 { 1455 struct ip_tunnel *t = netdev_priv(dev); 1456 struct ip_tunnel_parm_kern p; 1457 __u32 fwmark = t->fwmark; 1458 int err; 1459 1460 if (!rtnl_dev_link_net_capable(dev, t->net)) 1461 return -EPERM; 1462 1463 err = ipgre_newlink_encap_setup(dev, data); 1464 if (err) 1465 return err; 1466 1467 err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); 1468 if (err < 0) 1469 return err; 1470 1471 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1472 if (err < 0) 1473 return err; 1474 1475 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1476 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1477 1478 ipgre_link_update(dev, !tb[IFLA_MTU]); 1479 1480 return 0; 1481 } 1482 1483 static int erspan_changelink(struct net_device *dev, struct nlattr *tb[], 1484 struct nlattr *data[], 1485 struct netlink_ext_ack *extack) 1486 { 1487 struct ip_tunnel *t = netdev_priv(dev); 1488 struct ip_tunnel_parm_kern p; 1489 __u32 fwmark = t->fwmark; 1490 int err; 1491 1492 if (!rtnl_dev_link_net_capable(dev, t->net)) 1493 return -EPERM; 1494 1495 err = ipgre_newlink_encap_setup(dev, data); 1496 if (err) 1497 return err; 1498 1499 err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); 1500 if (err < 0) 1501 return err; 1502 1503 err = ip_tunnel_changelink(dev, tb, &p, fwmark); 1504 if (err < 0) 1505 return err; 1506 1507 ip_tunnel_flags_copy(t->parms.i_flags, p.i_flags); 1508 ip_tunnel_flags_copy(t->parms.o_flags, p.o_flags); 1509 1510 return 0; 1511 } 1512 1513 static size_t ipgre_get_size(const struct net_device *dev) 1514 { 1515 return 1516 /* IFLA_GRE_LINK */ 1517 nla_total_size(4) + 1518 /* IFLA_GRE_IFLAGS */ 1519 nla_total_size(2) + 1520 /* IFLA_GRE_OFLAGS */ 1521 nla_total_size(2) + 1522 /* IFLA_GRE_IKEY */ 1523 nla_total_size(4) + 1524 /* IFLA_GRE_OKEY */ 1525 nla_total_size(4) + 1526 /* IFLA_GRE_LOCAL */ 1527 nla_total_size(4) + 1528 /* IFLA_GRE_REMOTE */ 1529 nla_total_size(4) + 1530 /* IFLA_GRE_TTL */ 1531 nla_total_size(1) + 1532 /* IFLA_GRE_TOS */ 1533 nla_total_size(1) + 1534 /* IFLA_GRE_PMTUDISC */ 1535 nla_total_size(1) + 1536 /* IFLA_GRE_ENCAP_TYPE */ 1537 nla_total_size(2) + 1538 /* IFLA_GRE_ENCAP_FLAGS */ 1539 nla_total_size(2) + 1540 /* IFLA_GRE_ENCAP_SPORT */ 1541 nla_total_size(2) + 1542 /* IFLA_GRE_ENCAP_DPORT */ 1543 nla_total_size(2) + 1544 /* IFLA_GRE_COLLECT_METADATA */ 1545 nla_total_size(0) + 1546 /* IFLA_GRE_IGNORE_DF */ 1547 nla_total_size(1) + 1548 /* IFLA_GRE_FWMARK */ 1549 nla_total_size(4) + 1550 /* IFLA_GRE_ERSPAN_INDEX */ 1551 nla_total_size(4) + 1552 /* IFLA_GRE_ERSPAN_VER */ 1553 nla_total_size(1) + 1554 /* IFLA_GRE_ERSPAN_DIR */ 1555 nla_total_size(1) + 1556 /* IFLA_GRE_ERSPAN_HWID */ 1557 nla_total_size(2) + 1558 0; 1559 } 1560 1561 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) 1562 { 1563 struct ip_tunnel *t = netdev_priv(dev); 1564 struct ip_tunnel_parm_kern *p = &t->parms; 1565 IP_TUNNEL_DECLARE_FLAGS(o_flags); 1566 1567 ip_tunnel_flags_copy(o_flags, p->o_flags); 1568 1569 if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || 1570 nla_put_be16(skb, IFLA_GRE_IFLAGS, 1571 gre_tnl_flags_to_gre_flags(p->i_flags)) || 1572 nla_put_be16(skb, IFLA_GRE_OFLAGS, 1573 gre_tnl_flags_to_gre_flags(o_flags)) || 1574 nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || 1575 nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || 1576 nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || 1577 nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || 1578 nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || 1579 nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || 1580 nla_put_u8(skb, IFLA_GRE_PMTUDISC, 1581 !!(p->iph.frag_off & htons(IP_DF))) || 1582 nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark)) 1583 goto nla_put_failure; 1584 1585 if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, 1586 t->encap.type) || 1587 nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, 1588 t->encap.sport) || 1589 nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, 1590 t->encap.dport) || 1591 nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, 1592 t->encap.flags)) 1593 goto nla_put_failure; 1594 1595 if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df)) 1596 goto nla_put_failure; 1597 1598 if (t->collect_md) { 1599 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) 1600 goto nla_put_failure; 1601 } 1602 1603 return 0; 1604 1605 nla_put_failure: 1606 return -EMSGSIZE; 1607 } 1608 1609 static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev) 1610 { 1611 struct ip_tunnel *t = netdev_priv(dev); 1612 1613 if (t->erspan_ver <= 2) { 1614 if (t->erspan_ver != 0 && !t->collect_md) 1615 __set_bit(IP_TUNNEL_KEY_BIT, t->parms.o_flags); 1616 1617 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) 1618 goto nla_put_failure; 1619 1620 if (t->erspan_ver == 1) { 1621 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) 1622 goto nla_put_failure; 1623 } else if (t->erspan_ver == 2) { 1624 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) 1625 goto nla_put_failure; 1626 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid)) 1627 goto nla_put_failure; 1628 } 1629 } 1630 1631 return ipgre_fill_info(skb, dev); 1632 1633 nla_put_failure: 1634 return -EMSGSIZE; 1635 } 1636 1637 static void erspan_setup(struct net_device *dev) 1638 { 1639 struct ip_tunnel *t = netdev_priv(dev); 1640 1641 ether_setup(dev); 1642 dev->max_mtu = 0; 1643 dev->netdev_ops = &erspan_netdev_ops; 1644 dev->priv_flags &= ~IFF_TX_SKB_SHARING; 1645 dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 1646 ip_tunnel_setup(dev, erspan_net_id); 1647 t->erspan_ver = 1; 1648 } 1649 1650 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { 1651 [IFLA_GRE_LINK] = { .type = NLA_U32 }, 1652 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, 1653 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, 1654 [IFLA_GRE_IKEY] = { .type = NLA_U32 }, 1655 [IFLA_GRE_OKEY] = { .type = NLA_U32 }, 1656 [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) }, 1657 [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, 1658 [IFLA_GRE_TTL] = { .type = NLA_U8 }, 1659 [IFLA_GRE_TOS] = { .type = NLA_U8 }, 1660 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, 1661 [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, 1662 [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, 1663 [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, 1664 [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, 1665 [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, 1666 [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 }, 1667 [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, 1668 [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 }, 1669 [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 }, 1670 [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 }, 1671 [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 }, 1672 }; 1673 1674 static struct rtnl_link_ops ipgre_link_ops __read_mostly = { 1675 .kind = "gre", 1676 .maxtype = IFLA_GRE_MAX, 1677 .policy = ipgre_policy, 1678 .priv_size = sizeof(struct ip_tunnel), 1679 .setup = ipgre_tunnel_setup, 1680 .validate = ipgre_tunnel_validate, 1681 .newlink = ipgre_newlink, 1682 .changelink = ipgre_changelink, 1683 .dellink = ip_tunnel_dellink, 1684 .get_size = ipgre_get_size, 1685 .fill_info = ipgre_fill_info, 1686 .get_link_net = ip_tunnel_get_link_net, 1687 }; 1688 1689 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { 1690 .kind = "gretap", 1691 .maxtype = IFLA_GRE_MAX, 1692 .policy = ipgre_policy, 1693 .priv_size = sizeof(struct ip_tunnel), 1694 .setup = ipgre_tap_setup, 1695 .validate = ipgre_tap_validate, 1696 .newlink = ipgre_newlink, 1697 .changelink = ipgre_changelink, 1698 .dellink = ip_tunnel_dellink, 1699 .get_size = ipgre_get_size, 1700 .fill_info = ipgre_fill_info, 1701 .get_link_net = ip_tunnel_get_link_net, 1702 }; 1703 1704 static struct rtnl_link_ops erspan_link_ops __read_mostly = { 1705 .kind = "erspan", 1706 .maxtype = IFLA_GRE_MAX, 1707 .policy = ipgre_policy, 1708 .priv_size = sizeof(struct ip_tunnel), 1709 .setup = erspan_setup, 1710 .validate = erspan_validate, 1711 .newlink = erspan_newlink, 1712 .changelink = erspan_changelink, 1713 .dellink = ip_tunnel_dellink, 1714 .get_size = ipgre_get_size, 1715 .fill_info = erspan_fill_info, 1716 .get_link_net = ip_tunnel_get_link_net, 1717 }; 1718 1719 struct net_device *gretap_fb_dev_create(struct net *net, const char *name, 1720 u8 name_assign_type) 1721 { 1722 struct rtnl_newlink_params params = { .src_net = net }; 1723 struct nlattr *tb[IFLA_MAX + 1]; 1724 struct net_device *dev; 1725 LIST_HEAD(list_kill); 1726 struct ip_tunnel *t; 1727 int err; 1728 1729 memset(&tb, 0, sizeof(tb)); 1730 params.tb = tb; 1731 1732 dev = rtnl_create_link(net, name, name_assign_type, 1733 &ipgre_tap_ops, tb, NULL); 1734 if (IS_ERR(dev)) 1735 return dev; 1736 1737 /* Configure flow based GRE device. */ 1738 t = netdev_priv(dev); 1739 t->collect_md = true; 1740 1741 err = ipgre_newlink(dev, ¶ms, NULL); 1742 if (err < 0) { 1743 free_netdev(dev); 1744 return ERR_PTR(err); 1745 } 1746 1747 /* openvswitch users expect packet sizes to be unrestricted, 1748 * so set the largest MTU we can. 1749 */ 1750 err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); 1751 if (err) 1752 goto out; 1753 1754 err = rtnl_configure_link(dev, NULL, 0, NULL); 1755 if (err < 0) 1756 goto out; 1757 1758 return dev; 1759 out: 1760 ip_tunnel_dellink(dev, &list_kill); 1761 unregister_netdevice_many(&list_kill); 1762 return ERR_PTR(err); 1763 } 1764 EXPORT_SYMBOL_GPL(gretap_fb_dev_create); 1765 1766 static int __net_init ipgre_tap_init_net(struct net *net) 1767 { 1768 return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); 1769 } 1770 1771 static void __net_exit ipgre_tap_exit_rtnl(struct net *net, 1772 struct list_head *dev_to_kill) 1773 { 1774 ip_tunnel_delete_net(net, gre_tap_net_id, &ipgre_tap_ops, dev_to_kill); 1775 } 1776 1777 static struct pernet_operations ipgre_tap_net_ops = { 1778 .init = ipgre_tap_init_net, 1779 .exit_rtnl = ipgre_tap_exit_rtnl, 1780 .id = &gre_tap_net_id, 1781 .size = sizeof(struct ip_tunnel_net), 1782 }; 1783 1784 static int __net_init erspan_init_net(struct net *net) 1785 { 1786 return ip_tunnel_init_net(net, erspan_net_id, 1787 &erspan_link_ops, "erspan0"); 1788 } 1789 1790 static void __net_exit erspan_exit_rtnl(struct net *net, 1791 struct list_head *dev_to_kill) 1792 { 1793 ip_tunnel_delete_net(net, erspan_net_id, &erspan_link_ops, dev_to_kill); 1794 } 1795 1796 static struct pernet_operations erspan_net_ops = { 1797 .init = erspan_init_net, 1798 .exit_rtnl = erspan_exit_rtnl, 1799 .id = &erspan_net_id, 1800 .size = sizeof(struct ip_tunnel_net), 1801 }; 1802 1803 static int __init ipgre_init(void) 1804 { 1805 int err; 1806 1807 pr_info("GRE over IPv4 tunneling driver\n"); 1808 1809 err = register_pernet_device(&ipgre_net_ops); 1810 if (err < 0) 1811 return err; 1812 1813 err = register_pernet_device(&ipgre_tap_net_ops); 1814 if (err < 0) 1815 goto pnet_tap_failed; 1816 1817 err = register_pernet_device(&erspan_net_ops); 1818 if (err < 0) 1819 goto pnet_erspan_failed; 1820 1821 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); 1822 if (err < 0) { 1823 pr_info("%s: can't add protocol\n", __func__); 1824 goto add_proto_failed; 1825 } 1826 1827 err = rtnl_link_register(&ipgre_link_ops); 1828 if (err < 0) 1829 goto rtnl_link_failed; 1830 1831 err = rtnl_link_register(&ipgre_tap_ops); 1832 if (err < 0) 1833 goto tap_ops_failed; 1834 1835 err = rtnl_link_register(&erspan_link_ops); 1836 if (err < 0) 1837 goto erspan_link_failed; 1838 1839 return 0; 1840 1841 erspan_link_failed: 1842 rtnl_link_unregister(&ipgre_tap_ops); 1843 tap_ops_failed: 1844 rtnl_link_unregister(&ipgre_link_ops); 1845 rtnl_link_failed: 1846 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1847 add_proto_failed: 1848 unregister_pernet_device(&erspan_net_ops); 1849 pnet_erspan_failed: 1850 unregister_pernet_device(&ipgre_tap_net_ops); 1851 pnet_tap_failed: 1852 unregister_pernet_device(&ipgre_net_ops); 1853 return err; 1854 } 1855 1856 static void __exit ipgre_fini(void) 1857 { 1858 rtnl_link_unregister(&ipgre_tap_ops); 1859 rtnl_link_unregister(&ipgre_link_ops); 1860 rtnl_link_unregister(&erspan_link_ops); 1861 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); 1862 unregister_pernet_device(&ipgre_tap_net_ops); 1863 unregister_pernet_device(&ipgre_net_ops); 1864 unregister_pernet_device(&erspan_net_ops); 1865 } 1866 1867 module_init(ipgre_init); 1868 module_exit(ipgre_fini); 1869 MODULE_DESCRIPTION("IPv4 GRE tunnels over IP library"); 1870 MODULE_LICENSE("GPL"); 1871 MODULE_ALIAS_RTNL_LINK("gre"); 1872 MODULE_ALIAS_RTNL_LINK("gretap"); 1873 MODULE_ALIAS_RTNL_LINK("erspan"); 1874 MODULE_ALIAS_NETDEV("gre0"); 1875 MODULE_ALIAS_NETDEV("gretap0"); 1876 MODULE_ALIAS_NETDEV("erspan0"); 1877