blob: c3123c9e1a8e9510511d14ca4ac58f5f63d09c46 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
8 *
9 * $Id: sit.c,v 1.53 2001/09/25 05:09:53 davem Exp $
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 *
16 * Changes:
17 * Roger Venning <r.venning@telstra.com>: 6to4 support
18 * Nate Thompson <nate@thebog.net>: 6to4 support
19 */
20
21#include <linux/config.h>
22#include <linux/module.h>
23#include <linux/errno.h>
24#include <linux/types.h>
25#include <linux/socket.h>
26#include <linux/sockios.h>
27#include <linux/sched.h>
28#include <linux/net.h>
29#include <linux/in6.h>
30#include <linux/netdevice.h>
31#include <linux/if_arp.h>
32#include <linux/icmp.h>
33#include <asm/uaccess.h>
34#include <linux/init.h>
35#include <linux/netfilter_ipv4.h>
36
37#include <net/sock.h>
38#include <net/snmp.h>
39
40#include <net/ipv6.h>
41#include <net/protocol.h>
42#include <net/transp_v6.h>
43#include <net/ip6_fib.h>
44#include <net/ip6_route.h>
45#include <net/ndisc.h>
46#include <net/addrconf.h>
47#include <net/ip.h>
48#include <net/udp.h>
49#include <net/icmp.h>
50#include <net/ipip.h>
51#include <net/inet_ecn.h>
52#include <net/xfrm.h>
53#include <net/dsfield.h>
54
55/*
56 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
57
58 For comments look at net/ipv4/ip_gre.c --ANK
59 */
60
61#define HASH_SIZE 16
62#define HASH(addr) ((addr^(addr>>4))&0xF)
63
64static int ipip6_fb_tunnel_init(struct net_device *dev);
65static int ipip6_tunnel_init(struct net_device *dev);
66static void ipip6_tunnel_setup(struct net_device *dev);
67
68static struct net_device *ipip6_fb_tunnel_dev;
69
70static struct ip_tunnel *tunnels_r_l[HASH_SIZE];
71static struct ip_tunnel *tunnels_r[HASH_SIZE];
72static struct ip_tunnel *tunnels_l[HASH_SIZE];
73static struct ip_tunnel *tunnels_wc[1];
74static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l };
75
76static DEFINE_RWLOCK(ipip6_lock);
77
78static struct ip_tunnel * ipip6_tunnel_lookup(u32 remote, u32 local)
79{
80 unsigned h0 = HASH(remote);
81 unsigned h1 = HASH(local);
82 struct ip_tunnel *t;
83
84 for (t = tunnels_r_l[h0^h1]; t; t = t->next) {
85 if (local == t->parms.iph.saddr &&
86 remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
87 return t;
88 }
89 for (t = tunnels_r[h0]; t; t = t->next) {
90 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
91 return t;
92 }
93 for (t = tunnels_l[h1]; t; t = t->next) {
94 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
95 return t;
96 }
97 if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
98 return t;
99 return NULL;
100}
101
102static struct ip_tunnel ** ipip6_bucket(struct ip_tunnel *t)
103{
104 u32 remote = t->parms.iph.daddr;
105 u32 local = t->parms.iph.saddr;
106 unsigned h = 0;
107 int prio = 0;
108
109 if (remote) {
110 prio |= 2;
111 h ^= HASH(remote);
112 }
113 if (local) {
114 prio |= 1;
115 h ^= HASH(local);
116 }
117 return &tunnels[prio][h];
118}
119
120static void ipip6_tunnel_unlink(struct ip_tunnel *t)
121{
122 struct ip_tunnel **tp;
123
124 for (tp = ipip6_bucket(t); *tp; tp = &(*tp)->next) {
125 if (t == *tp) {
126 write_lock_bh(&ipip6_lock);
127 *tp = t->next;
128 write_unlock_bh(&ipip6_lock);
129 break;
130 }
131 }
132}
133
134static void ipip6_tunnel_link(struct ip_tunnel *t)
135{
136 struct ip_tunnel **tp = ipip6_bucket(t);
137
138 t->next = *tp;
139 write_lock_bh(&ipip6_lock);
140 *tp = t;
141 write_unlock_bh(&ipip6_lock);
142}
143
144static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int create)
145{
146 u32 remote = parms->iph.daddr;
147 u32 local = parms->iph.saddr;
148 struct ip_tunnel *t, **tp, *nt;
149 struct net_device *dev;
150 unsigned h = 0;
151 int prio = 0;
152 char name[IFNAMSIZ];
153
154 if (remote) {
155 prio |= 2;
156 h ^= HASH(remote);
157 }
158 if (local) {
159 prio |= 1;
160 h ^= HASH(local);
161 }
162 for (tp = &tunnels[prio][h]; (t = *tp) != NULL; tp = &t->next) {
163 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
164 return t;
165 }
166 if (!create)
167 goto failed;
168
169 if (parms->name[0])
170 strlcpy(name, parms->name, IFNAMSIZ);
171 else {
172 int i;
173 for (i=1; i<100; i++) {
174 sprintf(name, "sit%d", i);
175 if (__dev_get_by_name(name) == NULL)
176 break;
177 }
178 if (i==100)
179 goto failed;
180 }
181
182 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
183 if (dev == NULL)
184 return NULL;
185
186 nt = dev->priv;
187 dev->init = ipip6_tunnel_init;
188 nt->parms = *parms;
189
190 if (register_netdevice(dev) < 0) {
191 free_netdev(dev);
192 goto failed;
193 }
194
195 dev_hold(dev);
196
197 ipip6_tunnel_link(nt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 return nt;
199
200failed:
201 return NULL;
202}
203
204static void ipip6_tunnel_uninit(struct net_device *dev)
205{
206 if (dev == ipip6_fb_tunnel_dev) {
207 write_lock_bh(&ipip6_lock);
208 tunnels_wc[0] = NULL;
209 write_unlock_bh(&ipip6_lock);
210 dev_put(dev);
211 } else {
212 ipip6_tunnel_unlink((struct ip_tunnel*)dev->priv);
213 dev_put(dev);
214 }
215}
216
217
218static void ipip6_err(struct sk_buff *skb, u32 info)
219{
220#ifndef I_WISH_WORLD_WERE_PERFECT
221
222/* It is not :-( All the routers (except for Linux) return only
223 8 bytes of packet payload. It means, that precise relaying of
224 ICMP in the real Internet is absolutely infeasible.
225 */
226 struct iphdr *iph = (struct iphdr*)skb->data;
227 int type = skb->h.icmph->type;
228 int code = skb->h.icmph->code;
229 struct ip_tunnel *t;
230
231 switch (type) {
232 default:
233 case ICMP_PARAMETERPROB:
234 return;
235
236 case ICMP_DEST_UNREACH:
237 switch (code) {
238 case ICMP_SR_FAILED:
239 case ICMP_PORT_UNREACH:
240 /* Impossible event. */
241 return;
242 case ICMP_FRAG_NEEDED:
243 /* Soft state for pmtu is maintained by IP core. */
244 return;
245 default:
246 /* All others are translated to HOST_UNREACH.
247 rfc2003 contains "deep thoughts" about NET_UNREACH,
248 I believe they are just ether pollution. --ANK
249 */
250 break;
251 }
252 break;
253 case ICMP_TIME_EXCEEDED:
254 if (code != ICMP_EXC_TTL)
255 return;
256 break;
257 }
258
259 read_lock(&ipip6_lock);
260 t = ipip6_tunnel_lookup(iph->daddr, iph->saddr);
261 if (t == NULL || t->parms.iph.daddr == 0)
262 goto out;
263 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
264 goto out;
265
266 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
267 t->err_count++;
268 else
269 t->err_count = 1;
270 t->err_time = jiffies;
271out:
272 read_unlock(&ipip6_lock);
273 return;
274#else
275 struct iphdr *iph = (struct iphdr*)dp;
276 int hlen = iph->ihl<<2;
277 struct ipv6hdr *iph6;
278 int type = skb->h.icmph->type;
279 int code = skb->h.icmph->code;
280 int rel_type = 0;
281 int rel_code = 0;
282 int rel_info = 0;
283 struct sk_buff *skb2;
284 struct rt6_info *rt6i;
285
286 if (len < hlen + sizeof(struct ipv6hdr))
287 return;
288 iph6 = (struct ipv6hdr*)(dp + hlen);
289
290 switch (type) {
291 default:
292 return;
293 case ICMP_PARAMETERPROB:
294 if (skb->h.icmph->un.gateway < hlen)
295 return;
296
297 /* So... This guy found something strange INSIDE encapsulated
298 packet. Well, he is fool, but what can we do ?
299 */
300 rel_type = ICMPV6_PARAMPROB;
301 rel_info = skb->h.icmph->un.gateway - hlen;
302 break;
303
304 case ICMP_DEST_UNREACH:
305 switch (code) {
306 case ICMP_SR_FAILED:
307 case ICMP_PORT_UNREACH:
308 /* Impossible event. */
309 return;
310 case ICMP_FRAG_NEEDED:
311 /* Too complicated case ... */
312 return;
313 default:
314 /* All others are translated to HOST_UNREACH.
315 rfc2003 contains "deep thoughts" about NET_UNREACH,
316 I believe, it is just ether pollution. --ANK
317 */
318 rel_type = ICMPV6_DEST_UNREACH;
319 rel_code = ICMPV6_ADDR_UNREACH;
320 break;
321 }
322 break;
323 case ICMP_TIME_EXCEEDED:
324 if (code != ICMP_EXC_TTL)
325 return;
326 rel_type = ICMPV6_TIME_EXCEED;
327 rel_code = ICMPV6_EXC_HOPLIMIT;
328 break;
329 }
330
331 /* Prepare fake skb to feed it to icmpv6_send */
332 skb2 = skb_clone(skb, GFP_ATOMIC);
333 if (skb2 == NULL)
334 return;
335 dst_release(skb2->dst);
336 skb2->dst = NULL;
337 skb_pull(skb2, skb->data - (u8*)iph6);
338 skb2->nh.raw = skb2->data;
339
340 /* Try to guess incoming interface */
341 rt6i = rt6_lookup(&iph6->saddr, NULL, NULL, 0);
342 if (rt6i && rt6i->rt6i_dev) {
343 skb2->dev = rt6i->rt6i_dev;
344
345 rt6i = rt6_lookup(&iph6->daddr, &iph6->saddr, NULL, 0);
346
347 if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) {
348 struct ip_tunnel * t = (struct ip_tunnel*)rt6i->rt6i_dev->priv;
349 if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) {
350 rel_type = ICMPV6_DEST_UNREACH;
351 rel_code = ICMPV6_ADDR_UNREACH;
352 }
353 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
354 }
355 }
356 kfree_skb(skb2);
357 return;
358#endif
359}
360
361static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
362{
363 if (INET_ECN_is_ce(iph->tos))
364 IP6_ECN_set_ce(skb->nh.ipv6h);
365}
366
367static int ipip6_rcv(struct sk_buff *skb)
368{
369 struct iphdr *iph;
370 struct ip_tunnel *tunnel;
371
372 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
373 goto out;
374
375 iph = skb->nh.iph;
376
377 read_lock(&ipip6_lock);
378 if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
379 secpath_reset(skb);
380 skb->mac.raw = skb->nh.raw;
381 skb->nh.raw = skb->data;
382 memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
383 skb->protocol = htons(ETH_P_IPV6);
384 skb->pkt_type = PACKET_HOST;
385 tunnel->stat.rx_packets++;
386 tunnel->stat.rx_bytes += skb->len;
387 skb->dev = tunnel->dev;
388 dst_release(skb->dst);
389 skb->dst = NULL;
390 nf_reset(skb);
391 ipip6_ecn_decapsulate(iph, skb);
392 netif_rx(skb);
393 read_unlock(&ipip6_lock);
394 return 0;
395 }
396
397 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PROT_UNREACH, 0);
398 kfree_skb(skb);
399 read_unlock(&ipip6_lock);
400out:
401 return 0;
402}
403
404/* Returns the embedded IPv4 address if the IPv6 address
405 comes from 6to4 (RFC 3056) addr space */
406
407static inline u32 try_6to4(struct in6_addr *v6dst)
408{
409 u32 dst = 0;
410
411 if (v6dst->s6_addr16[0] == htons(0x2002)) {
412 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
413 memcpy(&dst, &v6dst->s6_addr16[1], 4);
414 }
415 return dst;
416}
417
418/*
419 * This function assumes it is being called from dev_queue_xmit()
420 * and that skb is filled properly by that function.
421 */
422
423static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
424{
425 struct ip_tunnel *tunnel = (struct ip_tunnel*)dev->priv;
426 struct net_device_stats *stats = &tunnel->stat;
427 struct iphdr *tiph = &tunnel->parms.iph;
428 struct ipv6hdr *iph6 = skb->nh.ipv6h;
429 u8 tos = tunnel->parms.iph.tos;
430 struct rtable *rt; /* Route to the other host */
431 struct net_device *tdev; /* Device to other host */
432 struct iphdr *iph; /* Our new IP header */
433 int max_headroom; /* The extra header space needed */
434 u32 dst = tiph->daddr;
435 int mtu;
436 struct in6_addr *addr6;
437 int addr_type;
438
439 if (tunnel->recursion++) {
440 tunnel->stat.collisions++;
441 goto tx_error;
442 }
443
444 if (skb->protocol != htons(ETH_P_IPV6))
445 goto tx_error;
446
447 if (!dst)
448 dst = try_6to4(&iph6->daddr);
449
450 if (!dst) {
451 struct neighbour *neigh = NULL;
452
453 if (skb->dst)
454 neigh = skb->dst->neighbour;
455
456 if (neigh == NULL) {
457 if (net_ratelimit())
458 printk(KERN_DEBUG "sit: nexthop == NULL\n");
459 goto tx_error;
460 }
461
462 addr6 = (struct in6_addr*)&neigh->primary_key;
463 addr_type = ipv6_addr_type(addr6);
464
465 if (addr_type == IPV6_ADDR_ANY) {
466 addr6 = &skb->nh.ipv6h->daddr;
467 addr_type = ipv6_addr_type(addr6);
468 }
469
470 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
471 goto tx_error_icmp;
472
473 dst = addr6->s6_addr32[3];
474 }
475
476 {
477 struct flowi fl = { .nl_u = { .ip4_u =
478 { .daddr = dst,
479 .saddr = tiph->saddr,
480 .tos = RT_TOS(tos) } },
481 .oif = tunnel->parms.link,
482 .proto = IPPROTO_IPV6 };
483 if (ip_route_output_key(&rt, &fl)) {
484 tunnel->stat.tx_carrier_errors++;
485 goto tx_error_icmp;
486 }
487 }
488 if (rt->rt_type != RTN_UNICAST) {
489 ip_rt_put(rt);
490 tunnel->stat.tx_carrier_errors++;
491 goto tx_error_icmp;
492 }
493 tdev = rt->u.dst.dev;
494
495 if (tdev == dev) {
496 ip_rt_put(rt);
497 tunnel->stat.collisions++;
498 goto tx_error;
499 }
500
501 if (tiph->frag_off)
502 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
503 else
504 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
505
506 if (mtu < 68) {
507 tunnel->stat.collisions++;
508 ip_rt_put(rt);
509 goto tx_error;
510 }
511 if (mtu < IPV6_MIN_MTU)
512 mtu = IPV6_MIN_MTU;
513 if (tunnel->parms.iph.daddr && skb->dst)
514 skb->dst->ops->update_pmtu(skb->dst, mtu);
515
516 if (skb->len > mtu) {
517 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
518 ip_rt_put(rt);
519 goto tx_error;
520 }
521
522 if (tunnel->err_count > 0) {
523 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
524 tunnel->err_count--;
525 dst_link_failure(skb);
526 } else
527 tunnel->err_count = 0;
528 }
529
530 /*
531 * Okay, now see if we can stuff it in the buffer as-is.
532 */
533 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
534
535 if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
536 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
537 if (!new_skb) {
538 ip_rt_put(rt);
539 stats->tx_dropped++;
540 dev_kfree_skb(skb);
541 tunnel->recursion--;
542 return 0;
543 }
544 if (skb->sk)
545 skb_set_owner_w(new_skb, skb->sk);
546 dev_kfree_skb(skb);
547 skb = new_skb;
548 iph6 = skb->nh.ipv6h;
549 }
550
551 skb->h.raw = skb->nh.raw;
552 skb->nh.raw = skb_push(skb, sizeof(struct iphdr));
553 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
554 dst_release(skb->dst);
555 skb->dst = &rt->u.dst;
556
557 /*
558 * Push down and install the IPIP header.
559 */
560
561 iph = skb->nh.iph;
562 iph->version = 4;
563 iph->ihl = sizeof(struct iphdr)>>2;
564 if (mtu > IPV6_MIN_MTU)
565 iph->frag_off = htons(IP_DF);
566 else
567 iph->frag_off = 0;
568
569 iph->protocol = IPPROTO_IPV6;
570 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
571 iph->daddr = rt->rt_dst;
572 iph->saddr = rt->rt_src;
573
574 if ((iph->ttl = tiph->ttl) == 0)
575 iph->ttl = iph6->hop_limit;
576
577 nf_reset(skb);
578
579 IPTUNNEL_XMIT();
580 tunnel->recursion--;
581 return 0;
582
583tx_error_icmp:
584 dst_link_failure(skb);
585tx_error:
586 stats->tx_errors++;
587 dev_kfree_skb(skb);
588 tunnel->recursion--;
589 return 0;
590}
591
592static int
593ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
594{
595 int err = 0;
596 struct ip_tunnel_parm p;
597 struct ip_tunnel *t;
598
599 switch (cmd) {
600 case SIOCGETTUNNEL:
601 t = NULL;
602 if (dev == ipip6_fb_tunnel_dev) {
603 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
604 err = -EFAULT;
605 break;
606 }
607 t = ipip6_tunnel_locate(&p, 0);
608 }
609 if (t == NULL)
610 t = (struct ip_tunnel*)dev->priv;
611 memcpy(&p, &t->parms, sizeof(p));
612 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
613 err = -EFAULT;
614 break;
615
616 case SIOCADDTUNNEL:
617 case SIOCCHGTUNNEL:
618 err = -EPERM;
619 if (!capable(CAP_NET_ADMIN))
620 goto done;
621
622 err = -EFAULT;
623 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
624 goto done;
625
626 err = -EINVAL;
627 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
628 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
629 goto done;
630 if (p.iph.ttl)
631 p.iph.frag_off |= htons(IP_DF);
632
633 t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL);
634
635 if (dev != ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
636 if (t != NULL) {
637 if (t->dev != dev) {
638 err = -EEXIST;
639 break;
640 }
641 } else {
642 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
643 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
644 err = -EINVAL;
645 break;
646 }
647 t = (struct ip_tunnel*)dev->priv;
648 ipip6_tunnel_unlink(t);
649 t->parms.iph.saddr = p.iph.saddr;
650 t->parms.iph.daddr = p.iph.daddr;
651 memcpy(dev->dev_addr, &p.iph.saddr, 4);
652 memcpy(dev->broadcast, &p.iph.daddr, 4);
653 ipip6_tunnel_link(t);
654 netdev_state_change(dev);
655 }
656 }
657
658 if (t) {
659 err = 0;
660 if (cmd == SIOCCHGTUNNEL) {
661 t->parms.iph.ttl = p.iph.ttl;
662 t->parms.iph.tos = p.iph.tos;
663 }
664 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
665 err = -EFAULT;
666 } else
667 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
668 break;
669
670 case SIOCDELTUNNEL:
671 err = -EPERM;
672 if (!capable(CAP_NET_ADMIN))
673 goto done;
674
675 if (dev == ipip6_fb_tunnel_dev) {
676 err = -EFAULT;
677 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
678 goto done;
679 err = -ENOENT;
680 if ((t = ipip6_tunnel_locate(&p, 0)) == NULL)
681 goto done;
682 err = -EPERM;
683 if (t == ipip6_fb_tunnel_dev->priv)
684 goto done;
685 dev = t->dev;
686 }
687 err = unregister_netdevice(dev);
688 break;
689
690 default:
691 err = -EINVAL;
692 }
693
694done:
695 return err;
696}
697
698static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
699{
700 return &(((struct ip_tunnel*)dev->priv)->stat);
701}
702
703static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
704{
705 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
706 return -EINVAL;
707 dev->mtu = new_mtu;
708 return 0;
709}
710
711static void ipip6_tunnel_setup(struct net_device *dev)
712{
713 SET_MODULE_OWNER(dev);
714 dev->uninit = ipip6_tunnel_uninit;
715 dev->destructor = free_netdev;
716 dev->hard_start_xmit = ipip6_tunnel_xmit;
717 dev->get_stats = ipip6_tunnel_get_stats;
718 dev->do_ioctl = ipip6_tunnel_ioctl;
719 dev->change_mtu = ipip6_tunnel_change_mtu;
720
721 dev->type = ARPHRD_SIT;
722 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
723 dev->mtu = 1500 - sizeof(struct iphdr);
724 dev->flags = IFF_NOARP;
725 dev->iflink = 0;
726 dev->addr_len = 4;
727}
728
729static int ipip6_tunnel_init(struct net_device *dev)
730{
731 struct net_device *tdev = NULL;
732 struct ip_tunnel *tunnel;
733 struct iphdr *iph;
734
735 tunnel = (struct ip_tunnel*)dev->priv;
736 iph = &tunnel->parms.iph;
737
738 tunnel->dev = dev;
739 strcpy(tunnel->parms.name, dev->name);
740
741 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
742 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
743
744 if (iph->daddr) {
745 struct flowi fl = { .nl_u = { .ip4_u =
746 { .daddr = iph->daddr,
747 .saddr = iph->saddr,
748 .tos = RT_TOS(iph->tos) } },
749 .oif = tunnel->parms.link,
750 .proto = IPPROTO_IPV6 };
751 struct rtable *rt;
752 if (!ip_route_output_key(&rt, &fl)) {
753 tdev = rt->u.dst.dev;
754 ip_rt_put(rt);
755 }
756 dev->flags |= IFF_POINTOPOINT;
757 }
758
759 if (!tdev && tunnel->parms.link)
760 tdev = __dev_get_by_index(tunnel->parms.link);
761
762 if (tdev) {
763 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
764 dev->mtu = tdev->mtu - sizeof(struct iphdr);
765 if (dev->mtu < IPV6_MIN_MTU)
766 dev->mtu = IPV6_MIN_MTU;
767 }
768 dev->iflink = tunnel->parms.link;
769
770 return 0;
771}
772
Arnaldo Carvalho de Melo20380732005-08-16 02:18:02 -0300773static int __init ipip6_fb_tunnel_init(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774{
775 struct ip_tunnel *tunnel = dev->priv;
776 struct iphdr *iph = &tunnel->parms.iph;
777
778 tunnel->dev = dev;
779 strcpy(tunnel->parms.name, dev->name);
780
781 iph->version = 4;
782 iph->protocol = IPPROTO_IPV6;
783 iph->ihl = 5;
784 iph->ttl = 64;
785
786 dev_hold(dev);
787 tunnels_wc[0] = tunnel;
788 return 0;
789}
790
791static struct net_protocol sit_protocol = {
792 .handler = ipip6_rcv,
793 .err_handler = ipip6_err,
794};
795
Alexey Kuznetsovdb445752005-07-30 17:46:44 -0700796static void __exit sit_destroy_tunnels(void)
797{
798 int prio;
799
800 for (prio = 1; prio < 4; prio++) {
801 int h;
802 for (h = 0; h < HASH_SIZE; h++) {
803 struct ip_tunnel *t;
804 while ((t = tunnels[prio][h]) != NULL)
805 unregister_netdevice(t->dev);
806 }
807 }
808}
809
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810void __exit sit_cleanup(void)
811{
812 inet_del_protocol(&sit_protocol, IPPROTO_IPV6);
Alexey Kuznetsovdb445752005-07-30 17:46:44 -0700813
814 rtnl_lock();
815 sit_destroy_tunnels();
816 unregister_netdevice(ipip6_fb_tunnel_dev);
817 rtnl_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818}
819
820int __init sit_init(void)
821{
822 int err;
823
824 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
825
826 if (inet_add_protocol(&sit_protocol, IPPROTO_IPV6) < 0) {
827 printk(KERN_INFO "sit init: Can't add protocol\n");
828 return -EAGAIN;
829 }
830
831 ipip6_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
832 ipip6_tunnel_setup);
833 if (!ipip6_fb_tunnel_dev) {
834 err = -ENOMEM;
835 goto err1;
836 }
837
838 ipip6_fb_tunnel_dev->init = ipip6_fb_tunnel_init;
839
840 if ((err = register_netdev(ipip6_fb_tunnel_dev)))
841 goto err2;
842
843 out:
844 return err;
845 err2:
846 free_netdev(ipip6_fb_tunnel_dev);
847 err1:
848 inet_del_protocol(&sit_protocol, IPPROTO_IPV6);
849 goto out;
850}