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.Cox@linux.org) 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 int ipip_fb_tunnel_init(struct net_device *dev); 134 static int 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 dev->init = ipip_tunnel_init; 249 nt->parms = *parms; 250 251 if (register_netdevice(dev) < 0) 252 goto failed_free; 253 254 dev_hold(dev); 255 ipip_tunnel_link(ipn, nt); 256 return nt; 257 258 failed_free: 259 free_netdev(dev); 260 return NULL; 261 } 262 263 static void ipip_tunnel_uninit(struct net_device *dev) 264 { 265 struct net *net = dev_net(dev); 266 struct ipip_net *ipn = net_generic(net, ipip_net_id); 267 268 if (dev == ipn->fb_tunnel_dev) { 269 write_lock_bh(&ipip_lock); 270 ipn->tunnels_wc[0] = NULL; 271 write_unlock_bh(&ipip_lock); 272 } else 273 ipip_tunnel_unlink(ipn, netdev_priv(dev)); 274 dev_put(dev); 275 } 276 277 static int ipip_err(struct sk_buff *skb, u32 info) 278 { 279 280 /* All the routers (except for Linux) return only 281 8 bytes of packet payload. It means, that precise relaying of 282 ICMP in the real Internet is absolutely infeasible. 283 */ 284 struct iphdr *iph = (struct iphdr*)skb->data; 285 const int type = icmp_hdr(skb)->type; 286 const int code = icmp_hdr(skb)->code; 287 struct ip_tunnel *t; 288 int err; 289 290 switch (type) { 291 default: 292 case ICMP_PARAMETERPROB: 293 return 0; 294 295 case ICMP_DEST_UNREACH: 296 switch (code) { 297 case ICMP_SR_FAILED: 298 case ICMP_PORT_UNREACH: 299 /* Impossible event. */ 300 return 0; 301 case ICMP_FRAG_NEEDED: 302 /* Soft state for pmtu is maintained by IP core. */ 303 return 0; 304 default: 305 /* All others are translated to HOST_UNREACH. 306 rfc2003 contains "deep thoughts" about NET_UNREACH, 307 I believe they are just ether pollution. --ANK 308 */ 309 break; 310 } 311 break; 312 case ICMP_TIME_EXCEEDED: 313 if (code != ICMP_EXC_TTL) 314 return 0; 315 break; 316 } 317 318 err = -ENOENT; 319 320 read_lock(&ipip_lock); 321 t = ipip_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr); 322 if (t == NULL || t->parms.iph.daddr == 0) 323 goto out; 324 325 err = 0; 326 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) 327 goto out; 328 329 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO) 330 t->err_count++; 331 else 332 t->err_count = 1; 333 t->err_time = jiffies; 334 out: 335 read_unlock(&ipip_lock); 336 return err; 337 } 338 339 static inline void ipip_ecn_decapsulate(const struct iphdr *outer_iph, 340 struct sk_buff *skb) 341 { 342 struct iphdr *inner_iph = ip_hdr(skb); 343 344 if (INET_ECN_is_ce(outer_iph->tos)) 345 IP_ECN_set_ce(inner_iph); 346 } 347 348 static int ipip_rcv(struct sk_buff *skb) 349 { 350 struct ip_tunnel *tunnel; 351 const struct iphdr *iph = ip_hdr(skb); 352 353 read_lock(&ipip_lock); 354 if ((tunnel = ipip_tunnel_lookup(dev_net(skb->dev), 355 iph->saddr, iph->daddr)) != NULL) { 356 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { 357 read_unlock(&ipip_lock); 358 kfree_skb(skb); 359 return 0; 360 } 361 362 secpath_reset(skb); 363 364 skb->mac_header = skb->network_header; 365 skb_reset_network_header(skb); 366 skb->protocol = htons(ETH_P_IP); 367 skb->pkt_type = PACKET_HOST; 368 369 tunnel->dev->stats.rx_packets++; 370 tunnel->dev->stats.rx_bytes += skb->len; 371 skb->dev = tunnel->dev; 372 dst_release(skb->dst); 373 skb->dst = NULL; 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 int 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 (tunnel->recursion++) { 406 stats->collisions++; 407 goto tx_error; 408 } 409 410 if (skb->protocol != htons(ETH_P_IP)) 411 goto tx_error; 412 413 if (tos&1) 414 tos = old_iph->tos; 415 416 if (!dst) { 417 /* NBMA tunnel */ 418 if ((rt = skb->rtable) == NULL) { 419 stats->tx_fifo_errors++; 420 goto tx_error; 421 } 422 if ((dst = rt->rt_gateway) == 0) 423 goto tx_error_icmp; 424 } 425 426 { 427 struct flowi fl = { .oif = tunnel->parms.link, 428 .nl_u = { .ip4_u = 429 { .daddr = dst, 430 .saddr = tiph->saddr, 431 .tos = RT_TOS(tos) } }, 432 .proto = IPPROTO_IPIP }; 433 if (ip_route_output_key(dev_net(dev), &rt, &fl)) { 434 stats->tx_carrier_errors++; 435 goto tx_error_icmp; 436 } 437 } 438 tdev = rt->u.dst.dev; 439 440 if (tdev == dev) { 441 ip_rt_put(rt); 442 stats->collisions++; 443 goto tx_error; 444 } 445 446 if (tiph->frag_off) 447 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr); 448 else 449 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu; 450 451 if (mtu < 68) { 452 stats->collisions++; 453 ip_rt_put(rt); 454 goto tx_error; 455 } 456 if (skb->dst) 457 skb->dst->ops->update_pmtu(skb->dst, mtu); 458 459 df |= (old_iph->frag_off&htons(IP_DF)); 460 461 if ((old_iph->frag_off&htons(IP_DF)) && mtu < ntohs(old_iph->tot_len)) { 462 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); 463 ip_rt_put(rt); 464 goto tx_error; 465 } 466 467 if (tunnel->err_count > 0) { 468 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) { 469 tunnel->err_count--; 470 dst_link_failure(skb); 471 } else 472 tunnel->err_count = 0; 473 } 474 475 /* 476 * Okay, now see if we can stuff it in the buffer as-is. 477 */ 478 max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr)); 479 480 if (skb_headroom(skb) < max_headroom || skb_shared(skb) || 481 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { 482 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); 483 if (!new_skb) { 484 ip_rt_put(rt); 485 stats->tx_dropped++; 486 dev_kfree_skb(skb); 487 tunnel->recursion--; 488 return 0; 489 } 490 if (skb->sk) 491 skb_set_owner_w(new_skb, skb->sk); 492 dev_kfree_skb(skb); 493 skb = new_skb; 494 old_iph = ip_hdr(skb); 495 } 496 497 skb->transport_header = skb->network_header; 498 skb_push(skb, sizeof(struct iphdr)); 499 skb_reset_network_header(skb); 500 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 501 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | 502 IPSKB_REROUTED); 503 dst_release(skb->dst); 504 skb->dst = &rt->u.dst; 505 506 /* 507 * Push down and install the IPIP header. 508 */ 509 510 iph = ip_hdr(skb); 511 iph->version = 4; 512 iph->ihl = sizeof(struct iphdr)>>2; 513 iph->frag_off = df; 514 iph->protocol = IPPROTO_IPIP; 515 iph->tos = INET_ECN_encapsulate(tos, old_iph->tos); 516 iph->daddr = rt->rt_dst; 517 iph->saddr = rt->rt_src; 518 519 if ((iph->ttl = tiph->ttl) == 0) 520 iph->ttl = old_iph->ttl; 521 522 nf_reset(skb); 523 524 IPTUNNEL_XMIT(); 525 tunnel->recursion--; 526 return 0; 527 528 tx_error_icmp: 529 dst_link_failure(skb); 530 tx_error: 531 stats->tx_errors++; 532 dev_kfree_skb(skb); 533 tunnel->recursion--; 534 return 0; 535 } 536 537 static void ipip_tunnel_bind_dev(struct net_device *dev) 538 { 539 struct net_device *tdev = NULL; 540 struct ip_tunnel *tunnel; 541 struct iphdr *iph; 542 543 tunnel = netdev_priv(dev); 544 iph = &tunnel->parms.iph; 545 546 if (iph->daddr) { 547 struct flowi fl = { .oif = tunnel->parms.link, 548 .nl_u = { .ip4_u = 549 { .daddr = iph->daddr, 550 .saddr = iph->saddr, 551 .tos = RT_TOS(iph->tos) } }, 552 .proto = IPPROTO_IPIP }; 553 struct rtable *rt; 554 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) { 555 tdev = rt->u.dst.dev; 556 ip_rt_put(rt); 557 } 558 dev->flags |= IFF_POINTOPOINT; 559 } 560 561 if (!tdev && tunnel->parms.link) 562 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link); 563 564 if (tdev) { 565 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr); 566 dev->mtu = tdev->mtu - sizeof(struct iphdr); 567 } 568 dev->iflink = tunnel->parms.link; 569 } 570 571 static int 572 ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) 573 { 574 int err = 0; 575 struct ip_tunnel_parm p; 576 struct ip_tunnel *t; 577 struct net *net = dev_net(dev); 578 struct ipip_net *ipn = net_generic(net, ipip_net_id); 579 580 switch (cmd) { 581 case SIOCGETTUNNEL: 582 t = NULL; 583 if (dev == ipn->fb_tunnel_dev) { 584 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { 585 err = -EFAULT; 586 break; 587 } 588 t = ipip_tunnel_locate(net, &p, 0); 589 } 590 if (t == NULL) 591 t = netdev_priv(dev); 592 memcpy(&p, &t->parms, sizeof(p)); 593 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) 594 err = -EFAULT; 595 break; 596 597 case SIOCADDTUNNEL: 598 case SIOCCHGTUNNEL: 599 err = -EPERM; 600 if (!capable(CAP_NET_ADMIN)) 601 goto done; 602 603 err = -EFAULT; 604 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 605 goto done; 606 607 err = -EINVAL; 608 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP || 609 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF))) 610 goto done; 611 if (p.iph.ttl) 612 p.iph.frag_off |= htons(IP_DF); 613 614 t = ipip_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL); 615 616 if (dev != ipn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { 617 if (t != NULL) { 618 if (t->dev != dev) { 619 err = -EEXIST; 620 break; 621 } 622 } else { 623 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) || 624 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) { 625 err = -EINVAL; 626 break; 627 } 628 t = netdev_priv(dev); 629 ipip_tunnel_unlink(ipn, t); 630 t->parms.iph.saddr = p.iph.saddr; 631 t->parms.iph.daddr = p.iph.daddr; 632 memcpy(dev->dev_addr, &p.iph.saddr, 4); 633 memcpy(dev->broadcast, &p.iph.daddr, 4); 634 ipip_tunnel_link(ipn, t); 635 netdev_state_change(dev); 636 } 637 } 638 639 if (t) { 640 err = 0; 641 if (cmd == SIOCCHGTUNNEL) { 642 t->parms.iph.ttl = p.iph.ttl; 643 t->parms.iph.tos = p.iph.tos; 644 t->parms.iph.frag_off = p.iph.frag_off; 645 if (t->parms.link != p.link) { 646 t->parms.link = p.link; 647 ipip_tunnel_bind_dev(dev); 648 netdev_state_change(dev); 649 } 650 } 651 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p))) 652 err = -EFAULT; 653 } else 654 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); 655 break; 656 657 case SIOCDELTUNNEL: 658 err = -EPERM; 659 if (!capable(CAP_NET_ADMIN)) 660 goto done; 661 662 if (dev == ipn->fb_tunnel_dev) { 663 err = -EFAULT; 664 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) 665 goto done; 666 err = -ENOENT; 667 if ((t = ipip_tunnel_locate(net, &p, 0)) == NULL) 668 goto done; 669 err = -EPERM; 670 if (t->dev == ipn->fb_tunnel_dev) 671 goto done; 672 dev = t->dev; 673 } 674 unregister_netdevice(dev); 675 err = 0; 676 break; 677 678 default: 679 err = -EINVAL; 680 } 681 682 done: 683 return err; 684 } 685 686 static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu) 687 { 688 if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr)) 689 return -EINVAL; 690 dev->mtu = new_mtu; 691 return 0; 692 } 693 694 static void ipip_tunnel_setup(struct net_device *dev) 695 { 696 dev->uninit = ipip_tunnel_uninit; 697 dev->hard_start_xmit = ipip_tunnel_xmit; 698 dev->do_ioctl = ipip_tunnel_ioctl; 699 dev->change_mtu = ipip_tunnel_change_mtu; 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 } 710 711 static int ipip_tunnel_init(struct net_device *dev) 712 { 713 struct ip_tunnel *tunnel; 714 715 tunnel = netdev_priv(dev); 716 717 tunnel->dev = dev; 718 strcpy(tunnel->parms.name, dev->name); 719 720 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4); 721 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4); 722 723 ipip_tunnel_bind_dev(dev); 724 725 return 0; 726 } 727 728 static int ipip_fb_tunnel_init(struct net_device *dev) 729 { 730 struct ip_tunnel *tunnel = netdev_priv(dev); 731 struct iphdr *iph = &tunnel->parms.iph; 732 struct ipip_net *ipn = net_generic(dev_net(dev), ipip_net_id); 733 734 tunnel->dev = dev; 735 strcpy(tunnel->parms.name, dev->name); 736 737 iph->version = 4; 738 iph->protocol = IPPROTO_IPIP; 739 iph->ihl = 5; 740 741 dev_hold(dev); 742 ipn->tunnels_wc[0] = tunnel; 743 return 0; 744 } 745 746 static struct xfrm_tunnel ipip_handler = { 747 .handler = ipip_rcv, 748 .err_handler = ipip_err, 749 .priority = 1, 750 }; 751 752 static char banner[] __initdata = 753 KERN_INFO "IPv4 over IPv4 tunneling driver\n"; 754 755 static void ipip_destroy_tunnels(struct ipip_net *ipn) 756 { 757 int prio; 758 759 for (prio = 1; prio < 4; prio++) { 760 int h; 761 for (h = 0; h < HASH_SIZE; h++) { 762 struct ip_tunnel *t; 763 while ((t = ipn->tunnels[prio][h]) != NULL) 764 unregister_netdevice(t->dev); 765 } 766 } 767 } 768 769 static int ipip_init_net(struct net *net) 770 { 771 int err; 772 struct ipip_net *ipn; 773 774 err = -ENOMEM; 775 ipn = kzalloc(sizeof(struct ipip_net), GFP_KERNEL); 776 if (ipn == NULL) 777 goto err_alloc; 778 779 err = net_assign_generic(net, ipip_net_id, ipn); 780 if (err < 0) 781 goto err_assign; 782 783 ipn->tunnels[0] = ipn->tunnels_wc; 784 ipn->tunnels[1] = ipn->tunnels_l; 785 ipn->tunnels[2] = ipn->tunnels_r; 786 ipn->tunnels[3] = ipn->tunnels_r_l; 787 788 ipn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), 789 "tunl0", 790 ipip_tunnel_setup); 791 if (!ipn->fb_tunnel_dev) { 792 err = -ENOMEM; 793 goto err_alloc_dev; 794 } 795 796 ipn->fb_tunnel_dev->init = ipip_fb_tunnel_init; 797 dev_net_set(ipn->fb_tunnel_dev, net); 798 799 if ((err = register_netdev(ipn->fb_tunnel_dev))) 800 goto err_reg_dev; 801 802 return 0; 803 804 err_reg_dev: 805 free_netdev(ipn->fb_tunnel_dev); 806 err_alloc_dev: 807 /* nothing */ 808 err_assign: 809 kfree(ipn); 810 err_alloc: 811 return err; 812 } 813 814 static void ipip_exit_net(struct net *net) 815 { 816 struct ipip_net *ipn; 817 818 ipn = net_generic(net, ipip_net_id); 819 rtnl_lock(); 820 ipip_destroy_tunnels(ipn); 821 unregister_netdevice(ipn->fb_tunnel_dev); 822 rtnl_unlock(); 823 kfree(ipn); 824 } 825 826 static struct pernet_operations ipip_net_ops = { 827 .init = ipip_init_net, 828 .exit = ipip_exit_net, 829 }; 830 831 static int __init ipip_init(void) 832 { 833 int err; 834 835 printk(banner); 836 837 if (xfrm4_tunnel_register(&ipip_handler, AF_INET)) { 838 printk(KERN_INFO "ipip init: can't register tunnel\n"); 839 return -EAGAIN; 840 } 841 842 err = register_pernet_gen_device(&ipip_net_id, &ipip_net_ops); 843 if (err) 844 xfrm4_tunnel_deregister(&ipip_handler, AF_INET); 845 846 return err; 847 } 848 849 static void __exit ipip_fini(void) 850 { 851 if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET)) 852 printk(KERN_INFO "ipip close: can't deregister tunnel\n"); 853 854 unregister_pernet_gen_device(ipip_net_id, &ipip_net_ops); 855 } 856 857 module_init(ipip_init); 858 module_exit(ipip_fini); 859 MODULE_LICENSE("GPL"); 860