1 /* 2 * Linux NET3: IP/IP protocol decoder. 3 * 4 * Authors: 5 * Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95 6 * 7 * Fixes: 8 * Alan Cox : Merged and made usable non modular (its so tiny its silly as 9 * a module taking up 2 pages). 10 * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph) 11 * to keep ip_forward happy. 12 * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8). 13 * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL 14 * David Woodhouse : Perform some basic ICMP handling. 15 * IPIP Routing without decapsulation. 16 * Carlos Picoto : GRE over IP support 17 * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c. 18 * I do not want to merge them together. 19 * 20 * This program is free software; you can redistribute it and/or 21 * modify it under the terms of the GNU General Public License 22 * as published by the Free Software Foundation; either version 23 * 2 of the License, or (at your option) any later version. 24 * 25 */ 26 27 /* tunnel.c: an IP tunnel driver 28 29 The purpose of this driver is to provide an IP tunnel through 30 which you can tunnel network traffic transparently across subnets. 31 32 This was written by looking at Nick Holloway's dummy driver 33 Thanks for the great code! 34 35 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95 36 37 Minor tweaks: 38 Cleaned up the code a little and added some pre-1.3.0 tweaks. 39 dev->hard_header/hard_header_len changed to use no headers. 40 Comments/bracketing tweaked. 41 Made the tunnels use dev->name not tunnel: when error reporting. 42 Added tx_dropped stat 43 44 -Alan Cox (alan@lxorguk.ukuu.org.uk) 21 March 95 45 46 Reworked: 47 Changed to tunnel to destination gateway in addition to the 48 tunnel's pointopoint address 49 Almost completely rewritten 50 Note: There is currently no firewall or ICMP handling done. 51 52 -Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96 53 54 */ 55 56 /* Things I wish I had known when writing the tunnel driver: 57 58 When the tunnel_xmit() function is called, the skb contains the 59 packet to be sent (plus a great deal of extra info), and dev 60 contains the tunnel device that _we_ are. 61 62 When we are passed a packet, we are expected to fill in the 63 source address with our source IP address. 64 65 What is the proper way to allocate, copy and free a buffer? 66 After you allocate it, it is a "0 length" chunk of memory 67 starting at zero. If you want to add headers to the buffer 68 later, you'll have to call "skb_reserve(skb, amount)" with 69 the amount of memory you want reserved. Then, you call 70 "skb_put(skb, amount)" with the amount of space you want in 71 the buffer. skb_put() returns a pointer to the top (#0) of 72 that buffer. skb->len is set to the amount of space you have 73 "allocated" with skb_put(). You can then write up to skb->len 74 bytes to that buffer. If you need more, you can call skb_put() 75 again with the additional amount of space you need. You can 76 find out how much more space you can allocate by calling 77 "skb_tailroom(skb)". 78 Now, to add header space, call "skb_push(skb, header_len)". 79 This creates space at the beginning of the buffer and returns 80 a pointer to this new space. If later you need to strip a 81 header from a buffer, call "skb_pull(skb, header_len)". 82 skb_headroom() will return how much space is left at the top 83 of the buffer (before the main data). Remember, this headroom 84 space must be reserved before the skb_put() function is called. 85 */ 86 87 /* 88 This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c 89 90 For comments look at net/ipv4/ip_gre.c --ANK 91 */ 92 93 94 #include <linux/capability.h> 95 #include <linux/module.h> 96 #include <linux/types.h> 97 #include <linux/kernel.h> 98 #include <asm/uaccess.h> 99 #include <linux/skbuff.h> 100 #include <linux/netdevice.h> 101 #include <linux/in.h> 102 #include <linux/tcp.h> 103 #include <linux/udp.h> 104 #include <linux/if_arp.h> 105 #include <linux/mroute.h> 106 #include <linux/init.h> 107 #include <linux/netfilter_ipv4.h> 108 #include <linux/if_ether.h> 109 110 #include <net/sock.h> 111 #include <net/ip.h> 112 #include <net/icmp.h> 113 #include <net/ipip.h> 114 #include <net/inet_ecn.h> 115 #include <net/xfrm.h> 116 #include <net/net_namespace.h> 117 #include <net/netns/generic.h> 118 119 #define HASH_SIZE 16 120 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF) 121 122 static int ipip_net_id; 123 struct ipip_net { 124 struct ip_tunnel *tunnels_r_l[HASH_SIZE]; 125 struct ip_tunnel *tunnels_r[HASH_SIZE]; 126 struct ip_tunnel *tunnels_l[HASH_SIZE]; 127 struct ip_tunnel *tunnels_wc[1]; 128 struct ip_tunnel **tunnels[4]; 129 130 struct net_device *fb_tunnel_dev; 131 }; 132 133 static void ipip_fb_tunnel_init(struct net_device *dev); 134 static void ipip_tunnel_init(struct net_device *dev); 135 static void ipip_tunnel_setup(struct net_device *dev); 136 137 static DEFINE_RWLOCK(ipip_lock); 138 139 static struct ip_tunnel * ipip_tunnel_lookup(struct net *net, 140 __be32 remote, __be32 local) 141 { 142 unsigned h0 = HASH(remote); 143 unsigned h1 = HASH(local); 144 struct ip_tunnel *t; 145 struct ipip_net *ipn = net_generic(net, ipip_net_id); 146 147 for (t = ipn->tunnels_r_l[h0^h1]; t; t = t->next) { 148 if (local == t->parms.iph.saddr && 149 remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) 150 return t; 151 } 152 for (t = ipn->tunnels_r[h0]; t; t = t->next) { 153 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP)) 154 return t; 155 } 156 for (t = ipn->tunnels_l[h1]; t; t = t->next) { 157 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP)) 158 return t; 159 } 160 if ((t = ipn->tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP)) 161 return t; 162 return NULL; 163 } 164 165 static struct ip_tunnel **__ipip_bucket(struct ipip_net *ipn, 166 struct ip_tunnel_parm *parms) 167 { 168 __be32 remote = parms->iph.daddr; 169 __be32 local = parms->iph.saddr; 170 unsigned h = 0; 171 int prio = 0; 172 173 if (remote) { 174 prio |= 2; 175 h ^= HASH(remote); 176 } 177 if (local) { 178 prio |= 1; 179 h ^= HASH(local); 180 } 181 return &ipn->tunnels[prio][h]; 182 } 183 184 static inline struct ip_tunnel **ipip_bucket(struct ipip_net *ipn, 185 struct ip_tunnel *t) 186 { 187 return __ipip_bucket(ipn, &t->parms); 188 } 189 190 static void ipip_tunnel_unlink(struct ipip_net *ipn, struct ip_tunnel *t) 191 { 192 struct ip_tunnel **tp; 193 194 for (tp = ipip_bucket(ipn, t); *tp; tp = &(*tp)->next) { 195 if (t == *tp) { 196 write_lock_bh(&ipip_lock); 197 *tp = t->next; 198 write_unlock_bh(&ipip_lock); 199 break; 200 } 201 } 202 } 203 204 static void ipip_tunnel_link(struct ipip_net *ipn, struct ip_tunnel *t) 205 { 206 struct ip_tunnel **tp = ipip_bucket(ipn, t); 207 208 t->next = *tp; 209 write_lock_bh(&ipip_lock); 210 *tp = t; 211 write_unlock_bh(&ipip_lock); 212 } 213 214 static struct ip_tunnel * ipip_tunnel_locate(struct net *net, 215 struct ip_tunnel_parm *parms, int create) 216 { 217 __be32 remote = parms->iph.daddr; 218 __be32 local = parms->iph.saddr; 219 struct ip_tunnel *t, **tp, *nt; 220 struct net_device *dev; 221 char name[IFNAMSIZ]; 222 struct ipip_net *ipn = net_generic(net, ipip_net_id); 223 224 for (tp = __ipip_bucket(ipn, parms); (t = *tp) != NULL; tp = &t->next) { 225 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) 226 return t; 227 } 228 if (!create) 229 return NULL; 230 231 if (parms->name[0]) 232 strlcpy(name, parms->name, IFNAMSIZ); 233 else 234 sprintf(name, "tunl%%d"); 235 236 dev = alloc_netdev(sizeof(*t), name, ipip_tunnel_setup); 237 if (dev == NULL) 238 return NULL; 239 240 dev_net_set(dev, net); 241 242 if (strchr(name, '%')) { 243 if (dev_alloc_name(dev, name) < 0) 244 goto failed_free; 245 } 246 247 nt = netdev_priv(dev); 248 nt->parms = *parms; 249 250 ipip_tunnel_init(dev); 251 252 if (register_netdevice(dev) < 0) 253 goto failed_free; 254 255 dev_hold(dev); 256 ipip_tunnel_link(ipn, nt); 257 return nt; 258 259 failed_free: 260 free_netdev(dev); 261 return NULL; 262 } 263 264 static void ipip_tunnel_uninit(struct net_device *dev) 265 { 266 struct net *net = dev_net(dev); 267 struct ipip_net *ipn = net_generic(net, ipip_net_id); 268 269 if (dev == ipn->fb_tunnel_dev) { 270 write_lock_bh(&ipip_lock); 271 ipn->tunnels_wc[0] = NULL; 272 write_unlock_bh(&ipip_lock); 273 } else 274 ipip_tunnel_unlink(ipn, netdev_priv(dev)); 275 dev_put(dev); 276 } 277 278 static int ipip_err(struct sk_buff *skb, u32 info) 279 { 280 281 /* All the routers (except for Linux) return only 282 8 bytes of packet payload. It means, that precise relaying of 283 ICMP in the real Internet is absolutely infeasible. 284 */ 285 struct iphdr *iph = (struct iphdr *)skb->data; 286 const int type = icmp_hdr(skb)->type; 287 const int code = icmp_hdr(skb)->code; 288 struct ip_tunnel *t; 289 int err; 290 291 switch (type) { 292 default: 293 case ICMP_PARAMETERPROB: 294 return 0; 295 296 case ICMP_DEST_UNREACH: 297 switch (code) { 298 case ICMP_SR_FAILED: 299 case ICMP_PORT_UNREACH: 300 /* Impossible event. */ 301 return 0; 302 case ICMP_FRAG_NEEDED: 303 /* Soft state for pmtu is maintained by IP core. */ 304 return 0; 305 default: 306 /* All others are translated to HOST_UNREACH. 307 rfc2003 contains "deep thoughts" about NET_UNREACH, 308 I believe they are just ether pollution. --ANK 309 */ 310 break; 311 } 312 break; 313 case ICMP_TIME_EXCEEDED: 314 if (code != ICMP_EXC_TTL) 315 return 0; 316 break; 317 } 318 319 err = -ENOENT; 320 321 read_lock(&ipip_lock); 322 t = ipip_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr); 323 if (t == NULL || t->parms.iph.daddr == 0) 324 goto out; 325 326 err = 0; 327 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) 328 goto out; 329 330 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) 331 t->err_count++; 332 else 333 t->err_count = 1; 334 t->err_time = jiffies; 335 out: 336 read_unlock(&ipip_lock); 337 return err; 338 } 339 340 static inline void ipip_ecn_decapsulate(const struct iphdr *outer_iph, 341 struct sk_buff *skb) 342 { 343 struct iphdr *inner_iph = ip_hdr(skb); 344 345 if (INET_ECN_is_ce(outer_iph->tos)) 346 IP_ECN_set_ce(inner_iph); 347 } 348 349 static int ipip_rcv(struct sk_buff *skb) 350 { 351 struct ip_tunnel *tunnel; 352 const struct iphdr *iph = ip_hdr(skb); 353 354 read_lock(&ipip_lock); 355 if ((tunnel = ipip_tunnel_lookup(dev_net(skb->dev), 356 iph->saddr, iph->daddr)) != NULL) { 357 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { 358 read_unlock(&ipip_lock); 359 kfree_skb(skb); 360 return 0; 361 } 362 363 secpath_reset(skb); 364 365 skb->mac_header = skb->network_header; 366 skb_reset_network_header(skb); 367 skb->protocol = htons(ETH_P_IP); 368 skb->pkt_type = PACKET_HOST; 369 370 tunnel->dev->stats.rx_packets++; 371 tunnel->dev->stats.rx_bytes += skb->len; 372 skb->dev = tunnel->dev; 373 skb_dst_drop(skb); 374 nf_reset(skb); 375 ipip_ecn_decapsulate(iph, skb); 376 netif_rx(skb); 377 read_unlock(&ipip_lock); 378 return 0; 379 } 380 read_unlock(&ipip_lock); 381 382 return -1; 383 } 384 385 /* 386 * This function assumes it is being called from dev_queue_xmit() 387 * and that skb is filled properly by that function. 388 */ 389 390 static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) 391 { 392 struct ip_tunnel *tunnel = netdev_priv(dev); 393 struct net_device_stats *stats = &tunnel->dev->stats; 394 struct iphdr *tiph = &tunnel->parms.iph; 395 u8 tos = tunnel->parms.iph.tos; 396 __be16 df = tiph->frag_off; 397 struct rtable *rt; /* Route to the other host */ 398 struct net_device *tdev; /* Device to other host */ 399 struct iphdr *old_iph = ip_hdr(skb); 400 struct iphdr *iph; /* Our new IP header */ 401 unsigned int max_headroom; /* The extra header space needed */ 402 __be32 dst = tiph->daddr; 403 int mtu; 404 405 if (skb->protocol != htons(ETH_P_IP)) 406 goto tx_error; 407 408 if (tos&1) 409 tos = old_iph->tos; 410 411 if (!dst) { 412 /* NBMA tunnel */ 413 if ((rt = skb_rtable(skb)) == NULL) { 414 stats->tx_fifo_errors++; 415 goto tx_error; 416 } 417 if ((dst = rt->rt_gateway) == 0) 418 goto tx_error_icmp; 419 } 420 421 { 422 struct flowi fl = { .oif = tunnel->parms.link, 423 .nl_u = { .ip4_u = 424 { .daddr = dst, 425 .saddr = tiph->saddr, 426 .tos = RT_TOS(tos) } }, 427 .proto = IPPROTO_IPIP }; 428 if (ip_route_output_key(dev_net(dev), &rt, &fl)) { 429 stats->tx_carrier_errors++; 430 goto tx_error_icmp; 431 } 432 } 433 tdev = rt->u.dst.dev; 434 435 if (tdev == dev) { 436 ip_rt_put(rt); 437 stats->collisions++; 438 goto tx_error; 439 } 440 441 df |= old_iph->frag_off & htons(IP_DF); 442 443 if (df) { 444 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr); 445 446 if (mtu < 68) { 447 stats->collisions++; 448 ip_rt_put(rt); 449 goto tx_error; 450 } 451 452 if (skb_dst(skb)) 453 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu); 454 455 if ((old_iph->frag_off & htons(IP_DF)) && 456 mtu < ntohs(old_iph->tot_len)) { 457 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 458 htonl(mtu)); 459 ip_rt_put(rt); 460 goto tx_error; 461 } 462 } 463 464 if (tunnel->err_count > 0) { 465 if (time_before(jiffies, 466 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { 467 tunnel->err_count--; 468 dst_link_failure(skb); 469 } else 470 tunnel->err_count = 0; 471 } 472 473 /* 474 * Okay, now see if we can stuff it in the buffer as-is. 475 */ 476 max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr)); 477 478 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 479 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 480 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); 481 if (!new_skb) { 482 ip_rt_put(rt); 483 stats->tx_dropped++; 484 dev_kfree_skb(skb); 485 return NETDEV_TX_OK; 486 } 487 if (skb->sk) 488 skb_set_owner_w(new_skb, skb->sk); 489 dev_kfree_skb(skb); 490 skb = new_skb; 491 old_iph = ip_hdr(skb); 492 } 493 494 skb->transport_header = skb->network_header; 495 skb_push(skb, sizeof(struct iphdr)); 496 skb_reset_network_header(skb); 497 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 498 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | 499 IPSKB_REROUTED); 500 skb_dst_drop(skb); 501 skb_dst_set(skb, &rt->u.dst); 502 503 /* 504 * Push down and install the IPIP header. 505 */ 506 507 iph = ip_hdr(skb); 508 iph->version = 4; 509 iph->ihl = sizeof(struct iphdr)>>2; 510 iph->frag_off = df; 511 iph->protocol = IPPROTO_IPIP; 512 iph->tos = INET_ECN_encapsulate(tos, old_iph->tos); 513 iph->daddr = rt->rt_dst; 514 iph->saddr = rt->rt_src; 515 516 if ((iph->ttl = tiph->ttl) == 0) 517 iph->ttl = old_iph->ttl; 518 519 nf_reset(skb); 520 521 IPTUNNEL_XMIT(); 522 return NETDEV_TX_OK; 523 524 tx_error_icmp: 525 dst_link_failure(skb); 526 tx_error: 527 stats->tx_errors++; 528 dev_kfree_skb(skb); 529 return NETDEV_TX_OK; 530 } 531 532 static void ipip_tunnel_bind_dev(struct net_device *dev) 533 { 534 struct net_device *tdev = NULL; 535 struct ip_tunnel *tunnel; 536 struct iphdr *iph; 537 538 tunnel = netdev_priv(dev); 539 iph = &tunnel->parms.iph; 540 541 if (iph->daddr) { 542 struct flowi fl = { .oif = tunnel->parms.link, 543 .nl_u = { .ip4_u = 544 { .daddr = iph->daddr, 545 .saddr = iph->saddr, 546 .tos = RT_TOS(iph->tos) } }, 547 .proto = IPPROTO_IPIP }; 548 struct rtable *rt; 549 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) { 550 tdev = rt->u.dst.dev; 551 ip_rt_put(rt); 552 } 553 dev->flags |= IFF_POINTOPOINT; 554 } 555 556 if (!tdev && tunnel->parms.link) 557 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link); 558 559 if (tdev) { 560 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); 561 dev->mtu = tdev->mtu - sizeof(struct iphdr); 562 } 563 dev->iflink = tunnel->parms.link; 564 } 565 566 static int 567 ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) 568 { 569 int err = 0; 570 struct ip_tunnel_parm p; 571 struct ip_tunnel *t; 572 struct net *net = dev_net(dev); 573 struct ipip_net *ipn = net_generic(net, ipip_net_id); 574 575 switch (cmd) { 576 case SIOCGETTUNNEL: 577 t = NULL; 578 if (dev == ipn->fb_tunnel_dev) { 579 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 580 err = -EFAULT; 581 break; 582 } 583 t = ipip_tunnel_locate(net, &p, 0); 584 } 585 if (t == NULL) 586 t = netdev_priv(dev); 587 memcpy(&p, &t->parms, sizeof(p)); 588 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 589 err = -EFAULT; 590 break; 591 592 case SIOCADDTUNNEL: 593 case SIOCCHGTUNNEL: 594 err = -EPERM; 595 if (!capable(CAP_NET_ADMIN)) 596 goto done; 597 598 err = -EFAULT; 599 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 600 goto done; 601 602 err = -EINVAL; 603 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP || 604 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF))) 605 goto done; 606 if (p.iph.ttl) 607 p.iph.frag_off |= htons(IP_DF); 608 609 t = ipip_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL); 610 611 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 612 if (t != NULL) { 613 if (t->dev != dev) { 614 err = -EEXIST; 615 break; 616 } 617 } else { 618 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) || 619 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) { 620 err = -EINVAL; 621 break; 622 } 623 t = netdev_priv(dev); 624 ipip_tunnel_unlink(ipn, t); 625 t->parms.iph.saddr = p.iph.saddr; 626 t->parms.iph.daddr = p.iph.daddr; 627 memcpy(dev->dev_addr, &p.iph.saddr, 4); 628 memcpy(dev->broadcast, &p.iph.daddr, 4); 629 ipip_tunnel_link(ipn, t); 630 netdev_state_change(dev); 631 } 632 } 633 634 if (t) { 635 err = 0; 636 if (cmd == SIOCCHGTUNNEL) { 637 t->parms.iph.ttl = p.iph.ttl; 638 t->parms.iph.tos = p.iph.tos; 639 t->parms.iph.frag_off = p.iph.frag_off; 640 if (t->parms.link != p.link) { 641 t->parms.link = p.link; 642 ipip_tunnel_bind_dev(dev); 643 netdev_state_change(dev); 644 } 645 } 646 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) 647 err = -EFAULT; 648 } else 649 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 650 break; 651 652 case SIOCDELTUNNEL: 653 err = -EPERM; 654 if (!capable(CAP_NET_ADMIN)) 655 goto done; 656 657 if (dev == ipn->fb_tunnel_dev) { 658 err = -EFAULT; 659 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 660 goto done; 661 err = -ENOENT; 662 if ((t = ipip_tunnel_locate(net, &p, 0)) == NULL) 663 goto done; 664 err = -EPERM; 665 if (t->dev == ipn->fb_tunnel_dev) 666 goto done; 667 dev = t->dev; 668 } 669 unregister_netdevice(dev); 670 err = 0; 671 break; 672 673 default: 674 err = -EINVAL; 675 } 676 677 done: 678 return err; 679 } 680 681 static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu) 682 { 683 if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr)) 684 return -EINVAL; 685 dev->mtu = new_mtu; 686 return 0; 687 } 688 689 static const struct net_device_ops ipip_netdev_ops = { 690 .ndo_uninit = ipip_tunnel_uninit, 691 .ndo_start_xmit = ipip_tunnel_xmit, 692 .ndo_do_ioctl = ipip_tunnel_ioctl, 693 .ndo_change_mtu = ipip_tunnel_change_mtu, 694 695 }; 696 697 static void ipip_tunnel_setup(struct net_device *dev) 698 { 699 dev->netdev_ops = &ipip_netdev_ops; 700 dev->destructor = free_netdev; 701 702 dev->type = ARPHRD_TUNNEL; 703 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr); 704 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr); 705 dev->flags = IFF_NOARP; 706 dev->iflink = 0; 707 dev->addr_len = 4; 708 dev->features |= NETIF_F_NETNS_LOCAL; 709 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 710 } 711 712 static void ipip_tunnel_init(struct net_device *dev) 713 { 714 struct ip_tunnel *tunnel = netdev_priv(dev); 715 716 tunnel->dev = dev; 717 strcpy(tunnel->parms.name, dev->name); 718 719 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); 720 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); 721 722 ipip_tunnel_bind_dev(dev); 723 } 724 725 static void ipip_fb_tunnel_init(struct net_device *dev) 726 { 727 struct ip_tunnel *tunnel = netdev_priv(dev); 728 struct iphdr *iph = &tunnel->parms.iph; 729 struct ipip_net *ipn = net_generic(dev_net(dev), ipip_net_id); 730 731 tunnel->dev = dev; 732 strcpy(tunnel->parms.name, dev->name); 733 734 iph->version = 4; 735 iph->protocol = IPPROTO_IPIP; 736 iph->ihl = 5; 737 738 dev_hold(dev); 739 ipn->tunnels_wc[0] = tunnel; 740 } 741 742 static struct xfrm_tunnel ipip_handler = { 743 .handler = ipip_rcv, 744 .err_handler = ipip_err, 745 .priority = 1, 746 }; 747 748 static const char banner[] __initconst = 749 KERN_INFO "IPv4 over IPv4 tunneling driver\n"; 750 751 static void ipip_destroy_tunnels(struct ipip_net *ipn) 752 { 753 int prio; 754 755 for (prio = 1; prio < 4; prio++) { 756 int h; 757 for (h = 0; h < HASH_SIZE; h++) { 758 struct ip_tunnel *t; 759 while ((t = ipn->tunnels[prio][h]) != NULL) 760 unregister_netdevice(t->dev); 761 } 762 } 763 } 764 765 static int ipip_init_net(struct net *net) 766 { 767 int err; 768 struct ipip_net *ipn; 769 770 err = -ENOMEM; 771 ipn = kzalloc(sizeof(struct ipip_net), GFP_KERNEL); 772 if (ipn == NULL) 773 goto err_alloc; 774 775 err = net_assign_generic(net, ipip_net_id, ipn); 776 if (err < 0) 777 goto err_assign; 778 779 ipn->tunnels[0] = ipn->tunnels_wc; 780 ipn->tunnels[1] = ipn->tunnels_l; 781 ipn->tunnels[2] = ipn->tunnels_r; 782 ipn->tunnels[3] = ipn->tunnels_r_l; 783 784 ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), 785 "tunl0", 786 ipip_tunnel_setup); 787 if (!ipn->fb_tunnel_dev) { 788 err = -ENOMEM; 789 goto err_alloc_dev; 790 } 791 dev_net_set(ipn->fb_tunnel_dev, net); 792 793 ipip_fb_tunnel_init(ipn->fb_tunnel_dev); 794 795 if ((err = register_netdev(ipn->fb_tunnel_dev))) 796 goto err_reg_dev; 797 798 return 0; 799 800 err_reg_dev: 801 free_netdev(ipn->fb_tunnel_dev); 802 err_alloc_dev: 803 /* nothing */ 804 err_assign: 805 kfree(ipn); 806 err_alloc: 807 return err; 808 } 809 810 static void ipip_exit_net(struct net *net) 811 { 812 struct ipip_net *ipn; 813 814 ipn = net_generic(net, ipip_net_id); 815 rtnl_lock(); 816 ipip_destroy_tunnels(ipn); 817 unregister_netdevice(ipn->fb_tunnel_dev); 818 rtnl_unlock(); 819 kfree(ipn); 820 } 821 822 static struct pernet_operations ipip_net_ops = { 823 .init = ipip_init_net, 824 .exit = ipip_exit_net, 825 }; 826 827 static int __init ipip_init(void) 828 { 829 int err; 830 831 printk(banner); 832 833 if (xfrm4_tunnel_register(&ipip_handler, AF_INET)) { 834 printk(KERN_INFO "ipip init: can't register tunnel\n"); 835 return -EAGAIN; 836 } 837 838 err = register_pernet_gen_device(&ipip_net_id, &ipip_net_ops); 839 if (err) 840 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 841 842 return err; 843 } 844 845 static void __exit ipip_fini(void) 846 { 847 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET)) 848 printk(KERN_INFO "ipip close: can't deregister tunnel\n"); 849 850 unregister_pernet_gen_device(ipip_net_id, &ipip_net_ops); 851 } 852 853 module_init(ipip_init); 854 module_exit(ipip_fini); 855 MODULE_LICENSE("GPL"); 856