[PATCH] EICON ISDN: Removed unused definitions for OS_SEEK_*
[wrt350n-kernel.git] / net / ipv6 / sit.c
blob836eecd7e62bfaa100a616d5aeda26ecc652ada9
1 /*
2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
3 * Linux INET6 implementation
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
9 * $Id: sit.c,v 1.53 2001/09/25 05:09:53 davem Exp $
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.
16 * Changes:
17 * Roger Venning <r.venning@telstra.com>: 6to4 support
18 * Nate Thompson <nate@thebog.net>: 6to4 support
21 #include <linux/module.h>
22 #include <linux/capability.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 #include <linux/if_ether.h>
38 #include <net/sock.h>
39 #include <net/snmp.h>
41 #include <net/ipv6.h>
42 #include <net/protocol.h>
43 #include <net/transp_v6.h>
44 #include <net/ip6_fib.h>
45 #include <net/ip6_route.h>
46 #include <net/ndisc.h>
47 #include <net/addrconf.h>
48 #include <net/ip.h>
49 #include <net/udp.h>
50 #include <net/icmp.h>
51 #include <net/ipip.h>
52 #include <net/inet_ecn.h>
53 #include <net/xfrm.h>
54 #include <net/dsfield.h>
57 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
59 For comments look at net/ipv4/ip_gre.c --ANK
62 #define HASH_SIZE 16
63 #define HASH(addr) ((addr^(addr>>4))&0xF)
65 static int ipip6_fb_tunnel_init(struct net_device *dev);
66 static int ipip6_tunnel_init(struct net_device *dev);
67 static void ipip6_tunnel_setup(struct net_device *dev);
69 static struct net_device *ipip6_fb_tunnel_dev;
71 static struct ip_tunnel *tunnels_r_l[HASH_SIZE];
72 static struct ip_tunnel *tunnels_r[HASH_SIZE];
73 static struct ip_tunnel *tunnels_l[HASH_SIZE];
74 static struct ip_tunnel *tunnels_wc[1];
75 static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l };
77 static DEFINE_RWLOCK(ipip6_lock);
79 static struct ip_tunnel * ipip6_tunnel_lookup(u32 remote, u32 local)
81 unsigned h0 = HASH(remote);
82 unsigned h1 = HASH(local);
83 struct ip_tunnel *t;
85 for (t = tunnels_r_l[h0^h1]; t; t = t->next) {
86 if (local == t->parms.iph.saddr &&
87 remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
88 return t;
90 for (t = tunnels_r[h0]; t; t = t->next) {
91 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
92 return t;
94 for (t = tunnels_l[h1]; t; t = t->next) {
95 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
96 return t;
98 if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
99 return t;
100 return NULL;
103 static struct ip_tunnel ** ipip6_bucket(struct ip_tunnel *t)
105 u32 remote = t->parms.iph.daddr;
106 u32 local = t->parms.iph.saddr;
107 unsigned h = 0;
108 int prio = 0;
110 if (remote) {
111 prio |= 2;
112 h ^= HASH(remote);
114 if (local) {
115 prio |= 1;
116 h ^= HASH(local);
118 return &tunnels[prio][h];
121 static void ipip6_tunnel_unlink(struct ip_tunnel *t)
123 struct ip_tunnel **tp;
125 for (tp = ipip6_bucket(t); *tp; tp = &(*tp)->next) {
126 if (t == *tp) {
127 write_lock_bh(&ipip6_lock);
128 *tp = t->next;
129 write_unlock_bh(&ipip6_lock);
130 break;
135 static void ipip6_tunnel_link(struct ip_tunnel *t)
137 struct ip_tunnel **tp = ipip6_bucket(t);
139 t->next = *tp;
140 write_lock_bh(&ipip6_lock);
141 *tp = t;
142 write_unlock_bh(&ipip6_lock);
145 static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int create)
147 u32 remote = parms->iph.daddr;
148 u32 local = parms->iph.saddr;
149 struct ip_tunnel *t, **tp, *nt;
150 struct net_device *dev;
151 unsigned h = 0;
152 int prio = 0;
153 char name[IFNAMSIZ];
155 if (remote) {
156 prio |= 2;
157 h ^= HASH(remote);
159 if (local) {
160 prio |= 1;
161 h ^= HASH(local);
163 for (tp = &tunnels[prio][h]; (t = *tp) != NULL; tp = &t->next) {
164 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
165 return t;
167 if (!create)
168 goto failed;
170 if (parms->name[0])
171 strlcpy(name, parms->name, IFNAMSIZ);
172 else {
173 int i;
174 for (i=1; i<100; i++) {
175 sprintf(name, "sit%d", i);
176 if (__dev_get_by_name(name) == NULL)
177 break;
179 if (i==100)
180 goto failed;
183 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
184 if (dev == NULL)
185 return NULL;
187 nt = netdev_priv(dev);
188 dev->init = ipip6_tunnel_init;
189 nt->parms = *parms;
191 if (register_netdevice(dev) < 0) {
192 free_netdev(dev);
193 goto failed;
196 dev_hold(dev);
198 ipip6_tunnel_link(nt);
199 return nt;
201 failed:
202 return NULL;
205 static void ipip6_tunnel_uninit(struct net_device *dev)
207 if (dev == ipip6_fb_tunnel_dev) {
208 write_lock_bh(&ipip6_lock);
209 tunnels_wc[0] = NULL;
210 write_unlock_bh(&ipip6_lock);
211 dev_put(dev);
212 } else {
213 ipip6_tunnel_unlink(netdev_priv(dev));
214 dev_put(dev);
219 static void ipip6_err(struct sk_buff *skb, u32 info)
221 #ifndef I_WISH_WORLD_WERE_PERFECT
223 /* It is not :-( All the routers (except for Linux) return only
224 8 bytes of packet payload. It means, that precise relaying of
225 ICMP in the real Internet is absolutely infeasible.
227 struct iphdr *iph = (struct iphdr*)skb->data;
228 int type = skb->h.icmph->type;
229 int code = skb->h.icmph->code;
230 struct ip_tunnel *t;
232 switch (type) {
233 default:
234 case ICMP_PARAMETERPROB:
235 return;
237 case ICMP_DEST_UNREACH:
238 switch (code) {
239 case ICMP_SR_FAILED:
240 case ICMP_PORT_UNREACH:
241 /* Impossible event. */
242 return;
243 case ICMP_FRAG_NEEDED:
244 /* Soft state for pmtu is maintained by IP core. */
245 return;
246 default:
247 /* All others are translated to HOST_UNREACH.
248 rfc2003 contains "deep thoughts" about NET_UNREACH,
249 I believe they are just ether pollution. --ANK
251 break;
253 break;
254 case ICMP_TIME_EXCEEDED:
255 if (code != ICMP_EXC_TTL)
256 return;
257 break;
260 read_lock(&ipip6_lock);
261 t = ipip6_tunnel_lookup(iph->daddr, iph->saddr);
262 if (t == NULL || t->parms.iph.daddr == 0)
263 goto out;
264 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
265 goto out;
267 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
268 t->err_count++;
269 else
270 t->err_count = 1;
271 t->err_time = jiffies;
272 out:
273 read_unlock(&ipip6_lock);
274 return;
275 #else
276 struct iphdr *iph = (struct iphdr*)dp;
277 int hlen = iph->ihl<<2;
278 struct ipv6hdr *iph6;
279 int type = skb->h.icmph->type;
280 int code = skb->h.icmph->code;
281 int rel_type = 0;
282 int rel_code = 0;
283 int rel_info = 0;
284 struct sk_buff *skb2;
285 struct rt6_info *rt6i;
287 if (len < hlen + sizeof(struct ipv6hdr))
288 return;
289 iph6 = (struct ipv6hdr*)(dp + hlen);
291 switch (type) {
292 default:
293 return;
294 case ICMP_PARAMETERPROB:
295 if (skb->h.icmph->un.gateway < hlen)
296 return;
298 /* So... This guy found something strange INSIDE encapsulated
299 packet. Well, he is fool, but what can we do ?
301 rel_type = ICMPV6_PARAMPROB;
302 rel_info = skb->h.icmph->un.gateway - hlen;
303 break;
305 case ICMP_DEST_UNREACH:
306 switch (code) {
307 case ICMP_SR_FAILED:
308 case ICMP_PORT_UNREACH:
309 /* Impossible event. */
310 return;
311 case ICMP_FRAG_NEEDED:
312 /* Too complicated case ... */
313 return;
314 default:
315 /* All others are translated to HOST_UNREACH.
316 rfc2003 contains "deep thoughts" about NET_UNREACH,
317 I believe, it is just ether pollution. --ANK
319 rel_type = ICMPV6_DEST_UNREACH;
320 rel_code = ICMPV6_ADDR_UNREACH;
321 break;
323 break;
324 case ICMP_TIME_EXCEEDED:
325 if (code != ICMP_EXC_TTL)
326 return;
327 rel_type = ICMPV6_TIME_EXCEED;
328 rel_code = ICMPV6_EXC_HOPLIMIT;
329 break;
332 /* Prepare fake skb to feed it to icmpv6_send */
333 skb2 = skb_clone(skb, GFP_ATOMIC);
334 if (skb2 == NULL)
335 return;
336 dst_release(skb2->dst);
337 skb2->dst = NULL;
338 skb_pull(skb2, skb->data - (u8*)iph6);
339 skb2->nh.raw = skb2->data;
341 /* Try to guess incoming interface */
342 rt6i = rt6_lookup(&iph6->saddr, NULL, NULL, 0);
343 if (rt6i && rt6i->rt6i_dev) {
344 skb2->dev = rt6i->rt6i_dev;
346 rt6i = rt6_lookup(&iph6->daddr, &iph6->saddr, NULL, 0);
348 if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) {
349 struct ip_tunnel *t = netdev_priv(rt6i->rt6i_dev);
350 if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) {
351 rel_type = ICMPV6_DEST_UNREACH;
352 rel_code = ICMPV6_ADDR_UNREACH;
354 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
357 kfree_skb(skb2);
358 return;
359 #endif
362 static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
364 if (INET_ECN_is_ce(iph->tos))
365 IP6_ECN_set_ce(skb->nh.ipv6h);
368 static int ipip6_rcv(struct sk_buff *skb)
370 struct iphdr *iph;
371 struct ip_tunnel *tunnel;
373 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
374 goto out;
376 iph = skb->nh.iph;
378 read_lock(&ipip6_lock);
379 if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
380 secpath_reset(skb);
381 skb->mac.raw = skb->nh.raw;
382 skb->nh.raw = skb->data;
383 IPCB(skb)->flags = 0;
384 skb->protocol = htons(ETH_P_IPV6);
385 skb->pkt_type = PACKET_HOST;
386 tunnel->stat.rx_packets++;
387 tunnel->stat.rx_bytes += skb->len;
388 skb->dev = tunnel->dev;
389 dst_release(skb->dst);
390 skb->dst = NULL;
391 nf_reset(skb);
392 ipip6_ecn_decapsulate(iph, skb);
393 netif_rx(skb);
394 read_unlock(&ipip6_lock);
395 return 0;
398 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
399 kfree_skb(skb);
400 read_unlock(&ipip6_lock);
401 out:
402 return 0;
405 /* Returns the embedded IPv4 address if the IPv6 address
406 comes from 6to4 (RFC 3056) addr space */
408 static inline u32 try_6to4(struct in6_addr *v6dst)
410 u32 dst = 0;
412 if (v6dst->s6_addr16[0] == htons(0x2002)) {
413 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
414 memcpy(&dst, &v6dst->s6_addr16[1], 4);
416 return dst;
420 * This function assumes it is being called from dev_queue_xmit()
421 * and that skb is filled properly by that function.
424 static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
426 struct ip_tunnel *tunnel = netdev_priv(dev);
427 struct net_device_stats *stats = &tunnel->stat;
428 struct iphdr *tiph = &tunnel->parms.iph;
429 struct ipv6hdr *iph6 = skb->nh.ipv6h;
430 u8 tos = tunnel->parms.iph.tos;
431 struct rtable *rt; /* Route to the other host */
432 struct net_device *tdev; /* Device to other host */
433 struct iphdr *iph; /* Our new IP header */
434 int max_headroom; /* The extra header space needed */
435 u32 dst = tiph->daddr;
436 int mtu;
437 struct in6_addr *addr6;
438 int addr_type;
440 if (tunnel->recursion++) {
441 tunnel->stat.collisions++;
442 goto tx_error;
445 if (skb->protocol != htons(ETH_P_IPV6))
446 goto tx_error;
448 if (!dst)
449 dst = try_6to4(&iph6->daddr);
451 if (!dst) {
452 struct neighbour *neigh = NULL;
454 if (skb->dst)
455 neigh = skb->dst->neighbour;
457 if (neigh == NULL) {
458 if (net_ratelimit())
459 printk(KERN_DEBUG "sit: nexthop == NULL\n");
460 goto tx_error;
463 addr6 = (struct in6_addr*)&neigh->primary_key;
464 addr_type = ipv6_addr_type(addr6);
466 if (addr_type == IPV6_ADDR_ANY) {
467 addr6 = &skb->nh.ipv6h->daddr;
468 addr_type = ipv6_addr_type(addr6);
471 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
472 goto tx_error_icmp;
474 dst = addr6->s6_addr32[3];
478 struct flowi fl = { .nl_u = { .ip4_u =
479 { .daddr = dst,
480 .saddr = tiph->saddr,
481 .tos = RT_TOS(tos) } },
482 .oif = tunnel->parms.link,
483 .proto = IPPROTO_IPV6 };
484 if (ip_route_output_key(&rt, &fl)) {
485 tunnel->stat.tx_carrier_errors++;
486 goto tx_error_icmp;
489 if (rt->rt_type != RTN_UNICAST) {
490 ip_rt_put(rt);
491 tunnel->stat.tx_carrier_errors++;
492 goto tx_error_icmp;
494 tdev = rt->u.dst.dev;
496 if (tdev == dev) {
497 ip_rt_put(rt);
498 tunnel->stat.collisions++;
499 goto tx_error;
502 if (tiph->frag_off)
503 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
504 else
505 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
507 if (mtu < 68) {
508 tunnel->stat.collisions++;
509 ip_rt_put(rt);
510 goto tx_error;
512 if (mtu < IPV6_MIN_MTU)
513 mtu = IPV6_MIN_MTU;
514 if (tunnel->parms.iph.daddr && skb->dst)
515 skb->dst->ops->update_pmtu(skb->dst, mtu);
517 if (skb->len > mtu) {
518 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
519 ip_rt_put(rt);
520 goto tx_error;
523 if (tunnel->err_count > 0) {
524 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
525 tunnel->err_count--;
526 dst_link_failure(skb);
527 } else
528 tunnel->err_count = 0;
532 * Okay, now see if we can stuff it in the buffer as-is.
534 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
536 if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
537 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
538 if (!new_skb) {
539 ip_rt_put(rt);
540 stats->tx_dropped++;
541 dev_kfree_skb(skb);
542 tunnel->recursion--;
543 return 0;
545 if (skb->sk)
546 skb_set_owner_w(new_skb, skb->sk);
547 dev_kfree_skb(skb);
548 skb = new_skb;
549 iph6 = skb->nh.ipv6h;
552 skb->h.raw = skb->nh.raw;
553 skb->nh.raw = skb_push(skb, sizeof(struct iphdr));
554 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
555 IPCB(skb)->flags = 0;
556 dst_release(skb->dst);
557 skb->dst = &rt->u.dst;
560 * Push down and install the IPIP header.
563 iph = skb->nh.iph;
564 iph->version = 4;
565 iph->ihl = sizeof(struct iphdr)>>2;
566 if (mtu > IPV6_MIN_MTU)
567 iph->frag_off = htons(IP_DF);
568 else
569 iph->frag_off = 0;
571 iph->protocol = IPPROTO_IPV6;
572 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
573 iph->daddr = rt->rt_dst;
574 iph->saddr = rt->rt_src;
576 if ((iph->ttl = tiph->ttl) == 0)
577 iph->ttl = iph6->hop_limit;
579 nf_reset(skb);
581 IPTUNNEL_XMIT();
582 tunnel->recursion--;
583 return 0;
585 tx_error_icmp:
586 dst_link_failure(skb);
587 tx_error:
588 stats->tx_errors++;
589 dev_kfree_skb(skb);
590 tunnel->recursion--;
591 return 0;
594 static int
595 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
597 int err = 0;
598 struct ip_tunnel_parm p;
599 struct ip_tunnel *t;
601 switch (cmd) {
602 case SIOCGETTUNNEL:
603 t = NULL;
604 if (dev == ipip6_fb_tunnel_dev) {
605 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
606 err = -EFAULT;
607 break;
609 t = ipip6_tunnel_locate(&p, 0);
611 if (t == NULL)
612 t = netdev_priv(dev);
613 memcpy(&p, &t->parms, sizeof(p));
614 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
615 err = -EFAULT;
616 break;
618 case SIOCADDTUNNEL:
619 case SIOCCHGTUNNEL:
620 err = -EPERM;
621 if (!capable(CAP_NET_ADMIN))
622 goto done;
624 err = -EFAULT;
625 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
626 goto done;
628 err = -EINVAL;
629 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
630 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
631 goto done;
632 if (p.iph.ttl)
633 p.iph.frag_off |= htons(IP_DF);
635 t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL);
637 if (dev != ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
638 if (t != NULL) {
639 if (t->dev != dev) {
640 err = -EEXIST;
641 break;
643 } else {
644 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
645 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
646 err = -EINVAL;
647 break;
649 t = netdev_priv(dev);
650 ipip6_tunnel_unlink(t);
651 t->parms.iph.saddr = p.iph.saddr;
652 t->parms.iph.daddr = p.iph.daddr;
653 memcpy(dev->dev_addr, &p.iph.saddr, 4);
654 memcpy(dev->broadcast, &p.iph.daddr, 4);
655 ipip6_tunnel_link(t);
656 netdev_state_change(dev);
660 if (t) {
661 err = 0;
662 if (cmd == SIOCCHGTUNNEL) {
663 t->parms.iph.ttl = p.iph.ttl;
664 t->parms.iph.tos = p.iph.tos;
666 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
667 err = -EFAULT;
668 } else
669 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
670 break;
672 case SIOCDELTUNNEL:
673 err = -EPERM;
674 if (!capable(CAP_NET_ADMIN))
675 goto done;
677 if (dev == ipip6_fb_tunnel_dev) {
678 err = -EFAULT;
679 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
680 goto done;
681 err = -ENOENT;
682 if ((t = ipip6_tunnel_locate(&p, 0)) == NULL)
683 goto done;
684 err = -EPERM;
685 if (t == netdev_priv(ipip6_fb_tunnel_dev))
686 goto done;
687 dev = t->dev;
689 err = unregister_netdevice(dev);
690 break;
692 default:
693 err = -EINVAL;
696 done:
697 return err;
700 static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
702 return &(((struct ip_tunnel*)netdev_priv(dev))->stat);
705 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
707 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
708 return -EINVAL;
709 dev->mtu = new_mtu;
710 return 0;
713 static void ipip6_tunnel_setup(struct net_device *dev)
715 SET_MODULE_OWNER(dev);
716 dev->uninit = ipip6_tunnel_uninit;
717 dev->destructor = free_netdev;
718 dev->hard_start_xmit = ipip6_tunnel_xmit;
719 dev->get_stats = ipip6_tunnel_get_stats;
720 dev->do_ioctl = ipip6_tunnel_ioctl;
721 dev->change_mtu = ipip6_tunnel_change_mtu;
723 dev->type = ARPHRD_SIT;
724 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
725 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
726 dev->flags = IFF_NOARP;
727 dev->iflink = 0;
728 dev->addr_len = 4;
731 static int ipip6_tunnel_init(struct net_device *dev)
733 struct net_device *tdev = NULL;
734 struct ip_tunnel *tunnel;
735 struct iphdr *iph;
737 tunnel = netdev_priv(dev);
738 iph = &tunnel->parms.iph;
740 tunnel->dev = dev;
741 strcpy(tunnel->parms.name, dev->name);
743 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
744 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
746 if (iph->daddr) {
747 struct flowi fl = { .nl_u = { .ip4_u =
748 { .daddr = iph->daddr,
749 .saddr = iph->saddr,
750 .tos = RT_TOS(iph->tos) } },
751 .oif = tunnel->parms.link,
752 .proto = IPPROTO_IPV6 };
753 struct rtable *rt;
754 if (!ip_route_output_key(&rt, &fl)) {
755 tdev = rt->u.dst.dev;
756 ip_rt_put(rt);
758 dev->flags |= IFF_POINTOPOINT;
761 if (!tdev && tunnel->parms.link)
762 tdev = __dev_get_by_index(tunnel->parms.link);
764 if (tdev) {
765 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
766 dev->mtu = tdev->mtu - sizeof(struct iphdr);
767 if (dev->mtu < IPV6_MIN_MTU)
768 dev->mtu = IPV6_MIN_MTU;
770 dev->iflink = tunnel->parms.link;
772 return 0;
775 static int __init ipip6_fb_tunnel_init(struct net_device *dev)
777 struct ip_tunnel *tunnel = netdev_priv(dev);
778 struct iphdr *iph = &tunnel->parms.iph;
780 tunnel->dev = dev;
781 strcpy(tunnel->parms.name, dev->name);
783 iph->version = 4;
784 iph->protocol = IPPROTO_IPV6;
785 iph->ihl = 5;
786 iph->ttl = 64;
788 dev_hold(dev);
789 tunnels_wc[0] = tunnel;
790 return 0;
793 static struct net_protocol sit_protocol = {
794 .handler = ipip6_rcv,
795 .err_handler = ipip6_err,
798 static void __exit sit_destroy_tunnels(void)
800 int prio;
802 for (prio = 1; prio < 4; prio++) {
803 int h;
804 for (h = 0; h < HASH_SIZE; h++) {
805 struct ip_tunnel *t;
806 while ((t = tunnels[prio][h]) != NULL)
807 unregister_netdevice(t->dev);
812 void __exit sit_cleanup(void)
814 inet_del_protocol(&sit_protocol, IPPROTO_IPV6);
816 rtnl_lock();
817 sit_destroy_tunnels();
818 unregister_netdevice(ipip6_fb_tunnel_dev);
819 rtnl_unlock();
822 int __init sit_init(void)
824 int err;
826 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
828 if (inet_add_protocol(&sit_protocol, IPPROTO_IPV6) < 0) {
829 printk(KERN_INFO "sit init: Can't add protocol\n");
830 return -EAGAIN;
833 ipip6_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
834 ipip6_tunnel_setup);
835 if (!ipip6_fb_tunnel_dev) {
836 err = -ENOMEM;
837 goto err1;
840 ipip6_fb_tunnel_dev->init = ipip6_fb_tunnel_init;
842 if ((err = register_netdev(ipip6_fb_tunnel_dev)))
843 goto err2;
845 out:
846 return err;
847 err2:
848 free_netdev(ipip6_fb_tunnel_dev);
849 err1:
850 inet_del_protocol(&sit_protocol, IPPROTO_IPV6);
851 goto out;