1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Linux NET3: IP/IP protocol decoder. 4 * 5 * Authors: 6 * Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95 7 * 8 * Fixes: 9 * Alan Cox : Merged and made usable non modular (its so tiny its silly as 10 * a module taking up 2 pages). 11 * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph) 12 * to keep ip_forward happy. 13 * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8). 14 * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL 15 * David Woodhouse : Perform some basic ICMP handling. 16 * IPIP Routing without decapsulation. 17 * Carlos Picoto : GRE over IP support 18 * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c. 19 * I do not want to merge them together. 20 */ 21 22 /* tunnel.c: an IP tunnel driver 23 24 The purpose of this driver is to provide an IP tunnel through 25 which you can tunnel network traffic transparently across subnets. 26 27 This was written by looking at Nick Holloway's dummy driver 28 Thanks for the great code! 29 30 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95 31 32 Minor tweaks: 33 Cleaned up the code a little and added some pre-1.3.0 tweaks. 34 dev->hard_header/hard_header_len changed to use no headers. 35 Comments/bracketing tweaked. 36 Made the tunnels use dev->name not tunnel: when error reporting. 37 Added tx_dropped stat 38 39 -Alan Cox (alan@lxorguk.ukuu.org.uk) 21 March 95 40 41 Reworked: 42 Changed to tunnel to destination gateway in addition to the 43 tunnel's pointopoint address 44 Almost completely rewritten 45 Note: There is currently no firewall or ICMP handling done. 46 47 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96 48 49 */ 50 51 /* Things I wish I had known when writing the tunnel driver: 52 53 When the tunnel_xmit() function is called, the skb contains the 54 packet to be sent (plus a great deal of extra info), and dev 55 contains the tunnel device that _we_ are. 56 57 When we are passed a packet, we are expected to fill in the 58 source address with our source IP address. 59 60 What is the proper way to allocate, copy and free a buffer? 61 After you allocate it, it is a "0 length" chunk of memory 62 starting at zero. If you want to add headers to the buffer 63 later, you'll have to call "skb_reserve(skb, amount)" with 64 the amount of memory you want reserved. Then, you call 65 "skb_put(skb, amount)" with the amount of space you want in 66 the buffer. skb_put() returns a pointer to the top (#0) of 67 that buffer. skb->len is set to the amount of space you have 68 "allocated" with skb_put(). You can then write up to skb->len 69 bytes to that buffer. If you need more, you can call skb_put() 70 again with the additional amount of space you need. You can 71 find out how much more space you can allocate by calling 72 "skb_tailroom(skb)". 73 Now, to add header space, call "skb_push(skb, header_len)". 74 This creates space at the beginning of the buffer and returns 75 a pointer to this new space. If later you need to strip a 76 header from a buffer, call "skb_pull(skb, header_len)". 77 skb_headroom() will return how much space is left at the top 78 of the buffer (before the main data). Remember, this headroom 79 space must be reserved before the skb_put() function is called. 80 */ 81 82 /* 83 This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c 84 85 For comments look at net/ipv4/ip_gre.c --ANK 86 */ 87 88 89 #include <linux/capability.h> 90 #include <linux/module.h> 91 #include <linux/types.h> 92 #include <linux/kernel.h> 93 #include <linux/slab.h> 94 #include <linux/uaccess.h> 95 #include <linux/skbuff.h> 96 #include <linux/netdevice.h> 97 #include <linux/in.h> 98 #include <linux/tcp.h> 99 #include <linux/udp.h> 100 #include <linux/if_arp.h> 101 #include <linux/init.h> 102 #include <linux/netfilter_ipv4.h> 103 #include <linux/if_ether.h> 104 105 #include <net/sock.h> 106 #include <net/ip.h> 107 #include <net/icmp.h> 108 #include <net/ip_tunnels.h> 109 #include <net/inet_ecn.h> 110 #include <net/xfrm.h> 111 #include <net/net_namespace.h> 112 #include <net/netns/generic.h> 113 #include <net/dst_metadata.h> 114 115 static bool log_ecn_error = true; 116 module_param(log_ecn_error, bool, 0644); 117 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); 118 119 static unsigned int ipip_net_id __read_mostly; 120 121 static int ipip_tunnel_init(struct net_device *dev); 122 static struct rtnl_link_ops ipip_link_ops __read_mostly; 123 124 static int ipip_err(struct sk_buff *skb, u32 info) 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 struct net *net = dev_net(skb->dev); 131 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id); 132 const struct iphdr *iph = (const struct iphdr *)skb->data; 133 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 134 const int type = icmp_hdr(skb)->type; 135 const int code = icmp_hdr(skb)->code; 136 struct ip_tunnel *t; 137 int err = 0; 138 139 __set_bit(IP_TUNNEL_NO_KEY_BIT, flags); 140 141 t = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, iph->daddr, 142 iph->saddr, 0); 143 if (!t) { 144 err = -ENOENT; 145 goto out; 146 } 147 148 switch (type) { 149 case ICMP_DEST_UNREACH: 150 switch (code) { 151 case ICMP_SR_FAILED: 152 /* Impossible event. */ 153 goto out; 154 default: 155 /* All others are translated to HOST_UNREACH. 156 * rfc2003 contains "deep thoughts" about NET_UNREACH, 157 * I believe they are just ether pollution. --ANK 158 */ 159 break; 160 } 161 break; 162 163 case ICMP_TIME_EXCEEDED: 164 if (code != ICMP_EXC_TTL) 165 goto out; 166 break; 167 168 case ICMP_REDIRECT: 169 break; 170 171 default: 172 goto out; 173 } 174 175 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { 176 ipv4_update_pmtu(skb, net, info, t->parms.link, iph->protocol); 177 goto out; 178 } 179 180 if (type == ICMP_REDIRECT) { 181 ipv4_redirect(skb, net, t->parms.link, iph->protocol); 182 goto out; 183 } 184 185 if (t->parms.iph.daddr == 0) { 186 err = -ENOENT; 187 goto out; 188 } 189 190 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) 191 goto out; 192 193 if (time_before(jiffies, READ_ONCE(t->err_time) + IPTUNNEL_ERR_TIMEO)) 194 WRITE_ONCE(t->err_count, READ_ONCE(t->err_count) + 1); 195 else 196 WRITE_ONCE(t->err_count, 1); 197 WRITE_ONCE(t->err_time, jiffies); 198 199 out: 200 return err; 201 } 202 203 static const struct tnl_ptk_info ipip_tpi = { 204 /* no tunnel info required for ipip. */ 205 .proto = htons(ETH_P_IP), 206 }; 207 208 #if IS_ENABLED(CONFIG_MPLS) 209 static const struct tnl_ptk_info mplsip_tpi = { 210 /* no tunnel info required for mplsip. */ 211 .proto = htons(ETH_P_MPLS_UC), 212 }; 213 #endif 214 215 static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto) 216 { 217 struct net *net = dev_net(skb->dev); 218 struct ip_tunnel_net *itn = net_generic(net, ipip_net_id); 219 IP_TUNNEL_DECLARE_FLAGS(flags) = { }; 220 struct metadata_dst *tun_dst = NULL; 221 struct ip_tunnel *tunnel; 222 const struct iphdr *iph; 223 224 __set_bit(IP_TUNNEL_NO_KEY_BIT, flags); 225 226 iph = ip_hdr(skb); 227 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, iph->saddr, 228 iph->daddr, 0); 229 if (tunnel) { 230 const struct tnl_ptk_info *tpi; 231 232 if (tunnel->parms.iph.protocol != ipproto && 233 tunnel->parms.iph.protocol != 0) 234 goto drop; 235 236 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) 237 goto drop; 238 #if IS_ENABLED(CONFIG_MPLS) 239 if (ipproto == IPPROTO_MPLS) 240 tpi = &mplsip_tpi; 241 else 242 #endif 243 tpi = &ipip_tpi; 244 if (iptunnel_pull_header(skb, 0, tpi->proto, false)) 245 goto drop; 246 if (tunnel->collect_md) { 247 ip_tunnel_flags_zero(flags); 248 249 tun_dst = ip_tun_rx_dst(skb, flags, 0, 0); 250 if (!tun_dst) 251 return 0; 252 ip_tunnel_md_udp_encap(skb, &tun_dst->u.tun_info); 253 } 254 skb_reset_mac_header(skb); 255 256 return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); 257 } 258 259 return -1; 260 261 drop: 262 kfree_skb(skb); 263 return 0; 264 } 265 266 static int ipip_rcv(struct sk_buff *skb) 267 { 268 return ipip_tunnel_rcv(skb, IPPROTO_IPIP); 269 } 270 271 #if IS_ENABLED(CONFIG_MPLS) 272 static int mplsip_rcv(struct sk_buff *skb) 273 { 274 return ipip_tunnel_rcv(skb, IPPROTO_MPLS); 275 } 276 #endif 277 278 /* 279 * This function assumes it is being called from dev_queue_xmit() 280 * and that skb is filled properly by that function. 281 */ 282 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, 283 struct net_device *dev) 284 { 285 struct ip_tunnel *tunnel = netdev_priv(dev); 286 const struct iphdr *tiph = &tunnel->parms.iph; 287 u8 ipproto; 288 289 if (!pskb_inet_may_pull(skb)) 290 goto tx_error; 291 292 switch (skb->protocol) { 293 case htons(ETH_P_IP): 294 ipproto = IPPROTO_IPIP; 295 break; 296 #if IS_ENABLED(CONFIG_MPLS) 297 case htons(ETH_P_MPLS_UC): 298 ipproto = IPPROTO_MPLS; 299 break; 300 #endif 301 default: 302 goto tx_error; 303 } 304 305 if (tiph->protocol != ipproto && tiph->protocol != 0) 306 goto tx_error; 307 308 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4)) 309 goto tx_error; 310 311 skb_set_inner_ipproto(skb, ipproto); 312 313 if (tunnel->collect_md) 314 ip_md_tunnel_xmit(skb, dev, ipproto, 0); 315 else 316 ip_tunnel_xmit(skb, dev, tiph, ipproto); 317 return NETDEV_TX_OK; 318 319 tx_error: 320 kfree_skb(skb); 321 322 DEV_STATS_INC(dev, tx_errors); 323 return NETDEV_TX_OK; 324 } 325 326 static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto) 327 { 328 switch (ipproto) { 329 case 0: 330 case IPPROTO_IPIP: 331 #if IS_ENABLED(CONFIG_MPLS) 332 case IPPROTO_MPLS: 333 #endif 334 return true; 335 } 336 337 return false; 338 } 339 340 static int 341 ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm_kern *p, int cmd) 342 { 343 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { 344 if (p->iph.version != 4 || 345 !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) || 346 p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF))) 347 return -EINVAL; 348 } 349 350 p->i_key = p->o_key = 0; 351 ip_tunnel_flags_zero(p->i_flags); 352 ip_tunnel_flags_zero(p->o_flags); 353 return ip_tunnel_ctl(dev, p, cmd); 354 } 355 356 static int ipip_fill_forward_path(struct net_device_path_ctx *ctx, 357 struct net_device_path *path) 358 { 359 struct ip_tunnel *tunnel = netdev_priv(ctx->dev); 360 const struct iphdr *tiph = &tunnel->parms.iph; 361 struct rtable *rt; 362 363 rt = ip_route_output(dev_net(ctx->dev), tiph->daddr, tiph->saddr, 364 inet_dsfield_to_dscp(tiph->tos), 365 tunnel->parms.link, RT_SCOPE_UNIVERSE); 366 if (IS_ERR(rt)) 367 return PTR_ERR(rt); 368 369 path->type = DEV_PATH_TUN; 370 path->tun.src_v4.s_addr = tiph->saddr; 371 path->tun.dst_v4.s_addr = tiph->daddr; 372 path->tun.l3_proto = IPPROTO_IPIP; 373 path->dev = ctx->dev; 374 375 ctx->dev = rt->dst.dev; 376 ip_rt_put(rt); 377 378 return 0; 379 } 380 381 static const struct net_device_ops ipip_netdev_ops = { 382 .ndo_init = ipip_tunnel_init, 383 .ndo_uninit = ip_tunnel_uninit, 384 .ndo_start_xmit = ipip_tunnel_xmit, 385 .ndo_siocdevprivate = ip_tunnel_siocdevprivate, 386 .ndo_change_mtu = ip_tunnel_change_mtu, 387 .ndo_get_stats64 = dev_get_tstats64, 388 .ndo_get_iflink = ip_tunnel_get_iflink, 389 .ndo_tunnel_ctl = ipip_tunnel_ctl, 390 .ndo_fill_forward_path = ipip_fill_forward_path, 391 }; 392 393 #define IPIP_FEATURES (NETIF_F_SG | \ 394 NETIF_F_FRAGLIST | \ 395 NETIF_F_HIGHDMA | \ 396 NETIF_F_GSO_SOFTWARE | \ 397 NETIF_F_HW_CSUM) 398 399 static void ipip_tunnel_setup(struct net_device *dev) 400 { 401 dev->netdev_ops = &ipip_netdev_ops; 402 dev->header_ops = &ip_tunnel_header_ops; 403 404 dev->type = ARPHRD_TUNNEL; 405 dev->flags = IFF_NOARP; 406 dev->addr_len = 4; 407 dev->lltx = true; 408 netif_keep_dst(dev); 409 410 dev->features |= IPIP_FEATURES; 411 dev->hw_features |= IPIP_FEATURES; 412 ip_tunnel_setup(dev, ipip_net_id); 413 } 414 415 static int ipip_tunnel_init(struct net_device *dev) 416 { 417 struct ip_tunnel *tunnel = netdev_priv(dev); 418 419 __dev_addr_set(dev, &tunnel->parms.iph.saddr, 4); 420 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); 421 422 tunnel->tun_hlen = 0; 423 tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; 424 return ip_tunnel_init(dev); 425 } 426 427 static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], 428 struct netlink_ext_ack *extack) 429 { 430 u8 proto; 431 432 if (!data || !data[IFLA_IPTUN_PROTO]) 433 return 0; 434 435 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); 436 if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0) 437 return -EINVAL; 438 439 return 0; 440 } 441 442 static void ipip_netlink_parms(struct nlattr *data[], 443 struct ip_tunnel_parm_kern *parms, 444 bool *collect_md, __u32 *fwmark) 445 { 446 memset(parms, 0, sizeof(*parms)); 447 448 parms->iph.version = 4; 449 parms->iph.protocol = IPPROTO_IPIP; 450 parms->iph.ihl = 5; 451 *collect_md = false; 452 453 if (!data) 454 return; 455 456 ip_tunnel_netlink_parms(data, parms); 457 458 if (data[IFLA_IPTUN_COLLECT_METADATA]) 459 *collect_md = true; 460 461 if (data[IFLA_IPTUN_FWMARK]) 462 *fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]); 463 } 464 465 static int ipip_newlink(struct net_device *dev, 466 struct rtnl_newlink_params *params, 467 struct netlink_ext_ack *extack) 468 { 469 struct ip_tunnel *t = netdev_priv(dev); 470 struct nlattr **data = params->data; 471 struct nlattr **tb = params->tb; 472 struct ip_tunnel_encap ipencap; 473 struct ip_tunnel_parm_kern p; 474 __u32 fwmark = 0; 475 476 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 477 int err = ip_tunnel_encap_setup(t, &ipencap); 478 479 if (err < 0) 480 return err; 481 } 482 483 ipip_netlink_parms(data, &p, &t->collect_md, &fwmark); 484 return ip_tunnel_newlink(params->link_net ? : dev_net(dev), dev, tb, &p, 485 fwmark); 486 } 487 488 static int ipip_changelink(struct net_device *dev, struct nlattr *tb[], 489 struct nlattr *data[], 490 struct netlink_ext_ack *extack) 491 { 492 struct ip_tunnel *t = netdev_priv(dev); 493 struct ip_tunnel_encap ipencap; 494 struct ip_tunnel_parm_kern p; 495 bool collect_md; 496 __u32 fwmark = t->fwmark; 497 498 if (!rtnl_dev_link_net_capable(dev, t->net)) 499 return -EPERM; 500 501 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) { 502 int err = ip_tunnel_encap_setup(t, &ipencap); 503 504 if (err < 0) 505 return err; 506 } 507 508 ipip_netlink_parms(data, &p, &collect_md, &fwmark); 509 if (collect_md) 510 return -EINVAL; 511 512 if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) || 513 (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr)) 514 return -EINVAL; 515 516 return ip_tunnel_changelink(dev, tb, &p, fwmark); 517 } 518 519 static size_t ipip_get_size(const struct net_device *dev) 520 { 521 return 522 /* IFLA_IPTUN_LINK */ 523 nla_total_size(4) + 524 /* IFLA_IPTUN_LOCAL */ 525 nla_total_size(4) + 526 /* IFLA_IPTUN_REMOTE */ 527 nla_total_size(4) + 528 /* IFLA_IPTUN_TTL */ 529 nla_total_size(1) + 530 /* IFLA_IPTUN_TOS */ 531 nla_total_size(1) + 532 /* IFLA_IPTUN_PROTO */ 533 nla_total_size(1) + 534 /* IFLA_IPTUN_PMTUDISC */ 535 nla_total_size(1) + 536 /* IFLA_IPTUN_ENCAP_TYPE */ 537 nla_total_size(2) + 538 /* IFLA_IPTUN_ENCAP_FLAGS */ 539 nla_total_size(2) + 540 /* IFLA_IPTUN_ENCAP_SPORT */ 541 nla_total_size(2) + 542 /* IFLA_IPTUN_ENCAP_DPORT */ 543 nla_total_size(2) + 544 /* IFLA_IPTUN_COLLECT_METADATA */ 545 nla_total_size(0) + 546 /* IFLA_IPTUN_FWMARK */ 547 nla_total_size(4) + 548 0; 549 } 550 551 static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev) 552 { 553 struct ip_tunnel *tunnel = netdev_priv(dev); 554 struct ip_tunnel_parm_kern *parm = &tunnel->parms; 555 556 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || 557 nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) || 558 nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) || 559 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) || 560 nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) || 561 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) || 562 nla_put_u8(skb, IFLA_IPTUN_PMTUDISC, 563 !!(parm->iph.frag_off & htons(IP_DF))) || 564 nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark)) 565 goto nla_put_failure; 566 567 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, 568 tunnel->encap.type) || 569 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, 570 tunnel->encap.sport) || 571 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, 572 tunnel->encap.dport) || 573 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, 574 tunnel->encap.flags)) 575 goto nla_put_failure; 576 577 if (tunnel->collect_md) 578 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA)) 579 goto nla_put_failure; 580 return 0; 581 582 nla_put_failure: 583 return -EMSGSIZE; 584 } 585 586 static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = { 587 [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, 588 [IFLA_IPTUN_LOCAL] = { .type = NLA_U32 }, 589 [IFLA_IPTUN_REMOTE] = { .type = NLA_U32 }, 590 [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, 591 [IFLA_IPTUN_TOS] = { .type = NLA_U8 }, 592 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, 593 [IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 }, 594 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 }, 595 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 }, 596 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 }, 597 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 }, 598 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG }, 599 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 }, 600 }; 601 602 static struct rtnl_link_ops ipip_link_ops __read_mostly = { 603 .kind = "ipip", 604 .maxtype = IFLA_IPTUN_MAX, 605 .policy = ipip_policy, 606 .priv_size = sizeof(struct ip_tunnel), 607 .setup = ipip_tunnel_setup, 608 .validate = ipip_tunnel_validate, 609 .newlink = ipip_newlink, 610 .changelink = ipip_changelink, 611 .dellink = ip_tunnel_dellink, 612 .get_size = ipip_get_size, 613 .fill_info = ipip_fill_info, 614 .get_link_net = ip_tunnel_get_link_net, 615 }; 616 617 static struct xfrm_tunnel ipip_handler __read_mostly = { 618 .handler = ipip_rcv, 619 .err_handler = ipip_err, 620 .priority = 1, 621 }; 622 623 #if IS_ENABLED(CONFIG_MPLS) 624 static struct xfrm_tunnel mplsip_handler __read_mostly = { 625 .handler = mplsip_rcv, 626 .err_handler = ipip_err, 627 .priority = 1, 628 }; 629 #endif 630 631 static int __net_init ipip_init_net(struct net *net) 632 { 633 return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0"); 634 } 635 636 static void __net_exit ipip_exit_rtnl(struct net *net, 637 struct list_head *dev_to_kill) 638 { 639 ip_tunnel_delete_net(net, ipip_net_id, &ipip_link_ops, dev_to_kill); 640 } 641 642 static struct pernet_operations ipip_net_ops = { 643 .init = ipip_init_net, 644 .exit_rtnl = ipip_exit_rtnl, 645 .id = &ipip_net_id, 646 .size = sizeof(struct ip_tunnel_net), 647 }; 648 649 static int __init ipip_init(void) 650 { 651 int err; 652 653 pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n"); 654 655 err = register_pernet_device(&ipip_net_ops); 656 if (err < 0) 657 return err; 658 err = xfrm4_tunnel_register(&ipip_handler, AF_INET); 659 if (err < 0) { 660 pr_info("%s: can't register tunnel\n", __func__); 661 goto xfrm_tunnel_ipip_failed; 662 } 663 #if IS_ENABLED(CONFIG_MPLS) 664 err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS); 665 if (err < 0) { 666 pr_info("%s: can't register tunnel\n", __func__); 667 goto xfrm_tunnel_mplsip_failed; 668 } 669 #endif 670 err = rtnl_link_register(&ipip_link_ops); 671 if (err < 0) 672 goto rtnl_link_failed; 673 674 out: 675 return err; 676 677 rtnl_link_failed: 678 #if IS_ENABLED(CONFIG_MPLS) 679 xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS); 680 xfrm_tunnel_mplsip_failed: 681 682 #endif 683 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 684 xfrm_tunnel_ipip_failed: 685 unregister_pernet_device(&ipip_net_ops); 686 goto out; 687 } 688 689 static void __exit ipip_fini(void) 690 { 691 rtnl_link_unregister(&ipip_link_ops); 692 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET)) 693 pr_info("%s: can't deregister tunnel\n", __func__); 694 #if IS_ENABLED(CONFIG_MPLS) 695 if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS)) 696 pr_info("%s: can't deregister tunnel\n", __func__); 697 #endif 698 unregister_pernet_device(&ipip_net_ops); 699 } 700 701 module_init(ipip_init); 702 module_exit(ipip_fini); 703 MODULE_DESCRIPTION("IP/IP protocol decoder library"); 704 MODULE_LICENSE("GPL"); 705 MODULE_ALIAS_RTNL_LINK("ipip"); 706 MODULE_ALIAS_NETDEV("tunl0"); 707