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[net-next-2.6.git] / net / ipv6 / sit.c
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1da177e4
LT		 1/*
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);
198 /* Do not decrement MOD_USE_COUNT here. */
199 return nt;
200
201failed:
202 return NULL;
203}
204
205static void ipip6_tunnel_uninit(struct net_device *dev)
206{
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((struct ip_tunnel*)dev->priv);
214 dev_put(dev);
215 }
216}
217
218
219static void ipip6_err(struct sk_buff *skb, u32 info)
220{
221#ifndef I_WISH_WORLD_WERE_PERFECT
222
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.
226 */
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;
231
232 switch (type) {
233 default:
234 case ICMP_PARAMETERPROB:
235 return;
236
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
250 */
251 break;
252 }
253 break;
254 case ICMP_TIME_EXCEEDED:
255 if (code != ICMP_EXC_TTL)
256 return;
257 break;
258 }
259
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;
266
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;
272out:
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;
286
287 if (len < hlen + sizeof(struct ipv6hdr))
288 return;
289 iph6 = (struct ipv6hdr*)(dp + hlen);
290
291 switch (type) {
292 default:
293 return;
294 case ICMP_PARAMETERPROB:
295 if (skb->h.icmph->un.gateway < hlen)
296 return;
297
298 /* So... This guy found something strange INSIDE encapsulated
299 packet. Well, he is fool, but what can we do ?
300 */
301 rel_type = ICMPV6_PARAMPROB;
302 rel_info = skb->h.icmph->un.gateway - hlen;
303 break;
304
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
318 */
319 rel_type = ICMPV6_DEST_UNREACH;
320 rel_code = ICMPV6_ADDR_UNREACH;
321 break;
322 }
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;
330 }
331
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;
340
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;
345
346 rt6i = rt6_lookup(&iph6->daddr, &iph6->saddr, NULL, 0);
347
348 if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) {
349 struct ip_tunnel * t = (struct ip_tunnel*)rt6i->rt6i_dev->priv;
350 if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) {
351 rel_type = ICMPV6_DEST_UNREACH;
352 rel_code = ICMPV6_ADDR_UNREACH;
353 }
354 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
355 }
356 }
357 kfree_skb(skb2);
358 return;
359#endif
360}
361
362static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
363{
364 if (INET_ECN_is_ce(iph->tos))
365 IP6_ECN_set_ce(skb->nh.ipv6h);
366}
367
368static int ipip6_rcv(struct sk_buff *skb)
369{
370 struct iphdr *iph;
371 struct ip_tunnel *tunnel;
372
373 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
374 goto out;
375
376 iph = skb->nh.iph;
377
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 memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
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;
396 }
397
398 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PROT_UNREACH, 0);
399 kfree_skb(skb);
400 read_unlock(&ipip6_lock);
401out:
402 return 0;
403}
404
405/* Returns the embedded IPv4 address if the IPv6 address
406 comes from 6to4 (RFC 3056) addr space */
407
408static inline u32 try_6to4(struct in6_addr *v6dst)
409{
410 u32 dst = 0;
411
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);
415 }
416 return dst;
417}
418
419/*
420 * This function assumes it is being called from dev_queue_xmit()
421 * and that skb is filled properly by that function.
422 */
423
424static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
425{
426 struct ip_tunnel *tunnel = (struct ip_tunnel*)dev->priv;
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;
439
440 if (tunnel->recursion++) {
441 tunnel->stat.collisions++;
442 goto tx_error;
443 }
444
445 if (skb->protocol != htons(ETH_P_IPV6))
446 goto tx_error;
447
448 if (!dst)
449 dst = try_6to4(&iph6->daddr);
450
451 if (!dst) {
452 struct neighbour *neigh = NULL;
453
454 if (skb->dst)
455 neigh = skb->dst->neighbour;
456
457 if (neigh == NULL) {
458 if (net_ratelimit())
459 printk(KERN_DEBUG "sit: nexthop == NULL\n");
460 goto tx_error;
461 }
462
463 addr6 = (struct in6_addr*)&neigh->primary_key;
464 addr_type = ipv6_addr_type(addr6);
465
466 if (addr_type == IPV6_ADDR_ANY) {
467 addr6 = &skb->nh.ipv6h->daddr;
468 addr_type = ipv6_addr_type(addr6);
469 }
470
471 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
472 goto tx_error_icmp;
473
474 dst = addr6->s6_addr32[3];
475 }
476
477 {
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;
487 }
488 }
489 if (rt->rt_type != RTN_UNICAST) {
490 ip_rt_put(rt);
491 tunnel->stat.tx_carrier_errors++;
492 goto tx_error_icmp;
493 }
494 tdev = rt->u.dst.dev;
495
496 if (tdev == dev) {
497 ip_rt_put(rt);
498 tunnel->stat.collisions++;
499 goto tx_error;
500 }
501
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;
506
507 if (mtu < 68) {
508 tunnel->stat.collisions++;
509 ip_rt_put(rt);
510 goto tx_error;
511 }
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);
516
517 if (skb->len > mtu) {
518 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
519 ip_rt_put(rt);
520 goto tx_error;
521 }
522
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;
529 }
530
531 /*
532 * Okay, now see if we can stuff it in the buffer as-is.
533 */
534 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
535
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;
544 }
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;
550 }
551
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 dst_release(skb->dst);
556 skb->dst = &rt->u.dst;
557
558 /*
559 * Push down and install the IPIP header.
560 */
561
562 iph = skb->nh.iph;
563 iph->version = 4;
564 iph->ihl = sizeof(struct iphdr)>>2;
565 if (mtu > IPV6_MIN_MTU)
566 iph->frag_off = htons(IP_DF);
567 else
568 iph->frag_off = 0;
569
570 iph->protocol = IPPROTO_IPV6;
571 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
572 iph->daddr = rt->rt_dst;
573 iph->saddr = rt->rt_src;
574
575 if ((iph->ttl = tiph->ttl) == 0)
576 iph->ttl = iph6->hop_limit;
577
578 nf_reset(skb);
579
580 IPTUNNEL_XMIT();
581 tunnel->recursion--;
582 return 0;
583
584tx_error_icmp:
585 dst_link_failure(skb);
586tx_error:
587 stats->tx_errors++;
588 dev_kfree_skb(skb);
589 tunnel->recursion--;
590 return 0;
591}
592
593static int
594ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
595{
596 int err = 0;
597 struct ip_tunnel_parm p;
598 struct ip_tunnel *t;
599
600 switch (cmd) {
601 case SIOCGETTUNNEL:
602 t = NULL;
603 if (dev == ipip6_fb_tunnel_dev) {
604 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
605 err = -EFAULT;
606 break;
607 }
608 t = ipip6_tunnel_locate(&p, 0);
609 }
610 if (t == NULL)
611 t = (struct ip_tunnel*)dev->priv;
612 memcpy(&p, &t->parms, sizeof(p));
613 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
614 err = -EFAULT;
615 break;
616
617 case SIOCADDTUNNEL:
618 case SIOCCHGTUNNEL:
619 err = -EPERM;
620 if (!capable(CAP_NET_ADMIN))
621 goto done;
622
623 err = -EFAULT;
624 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
625 goto done;
626
627 err = -EINVAL;
628 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
629 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
630 goto done;
631 if (p.iph.ttl)
632 p.iph.frag_off |= htons(IP_DF);
633
634 t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL);
635
636 if (dev != ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
637 if (t != NULL) {
638 if (t->dev != dev) {
639 err = -EEXIST;
640 break;
641 }
642 } else {
643 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
644 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
645 err = -EINVAL;
646 break;
647 }
648 t = (struct ip_tunnel*)dev->priv;
649 ipip6_tunnel_unlink(t);
650 t->parms.iph.saddr = p.iph.saddr;
651 t->parms.iph.daddr = p.iph.daddr;
652 memcpy(dev->dev_addr, &p.iph.saddr, 4);
653 memcpy(dev->broadcast, &p.iph.daddr, 4);
654 ipip6_tunnel_link(t);
655 netdev_state_change(dev);
656 }
657 }
658
659 if (t) {
660 err = 0;
661 if (cmd == SIOCCHGTUNNEL) {
662 t->parms.iph.ttl = p.iph.ttl;
663 t->parms.iph.tos = p.iph.tos;
664 }
665 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
666 err = -EFAULT;
667 } else
668 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
669 break;
670
671 case SIOCDELTUNNEL:
672 err = -EPERM;
673 if (!capable(CAP_NET_ADMIN))
674 goto done;
675
676 if (dev == ipip6_fb_tunnel_dev) {
677 err = -EFAULT;
678 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
679 goto done;
680 err = -ENOENT;
681 if ((t = ipip6_tunnel_locate(&p, 0)) == NULL)
682 goto done;
683 err = -EPERM;
684 if (t == ipip6_fb_tunnel_dev->priv)
685 goto done;
686 dev = t->dev;
687 }
688 err = unregister_netdevice(dev);
689 break;
690
691 default:
692 err = -EINVAL;
693 }
694
695done:
696 return err;
697}
698
699static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
700{
701 return &(((struct ip_tunnel*)dev->priv)->stat);
702}
703
704static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
705{
706 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
707 return -EINVAL;
708 dev->mtu = new_mtu;
709 return 0;
710}
711
712static void ipip6_tunnel_setup(struct net_device *dev)
713{
714 SET_MODULE_OWNER(dev);
715 dev->uninit = ipip6_tunnel_uninit;
716 dev->destructor = free_netdev;
717 dev->hard_start_xmit = ipip6_tunnel_xmit;
718 dev->get_stats = ipip6_tunnel_get_stats;
719 dev->do_ioctl = ipip6_tunnel_ioctl;
720 dev->change_mtu = ipip6_tunnel_change_mtu;
721
722 dev->type = ARPHRD_SIT;
723 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
724 dev->mtu = 1500 - sizeof(struct iphdr);
725 dev->flags = IFF_NOARP;
726 dev->iflink = 0;
727 dev->addr_len = 4;
728}
729
730static int ipip6_tunnel_init(struct net_device *dev)
731{
732 struct net_device *tdev = NULL;
733 struct ip_tunnel *tunnel;
734 struct iphdr *iph;
735
736 tunnel = (struct ip_tunnel*)dev->priv;
737 iph = &tunnel->parms.iph;
738
739 tunnel->dev = dev;
740 strcpy(tunnel->parms.name, dev->name);
741
742 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
743 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
744
745 if (iph->daddr) {
746 struct flowi fl = { .nl_u = { .ip4_u =
747 { .daddr = iph->daddr,
748 .saddr = iph->saddr,
749 .tos = RT_TOS(iph->tos) } },
750 .oif = tunnel->parms.link,
751 .proto = IPPROTO_IPV6 };
752 struct rtable *rt;
753 if (!ip_route_output_key(&rt, &fl)) {
754 tdev = rt->u.dst.dev;
755 ip_rt_put(rt);
756 }
757 dev->flags |= IFF_POINTOPOINT;
758 }
759
760 if (!tdev && tunnel->parms.link)
761 tdev = __dev_get_by_index(tunnel->parms.link);
762
763 if (tdev) {
764 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
765 dev->mtu = tdev->mtu - sizeof(struct iphdr);
766 if (dev->mtu < IPV6_MIN_MTU)
767 dev->mtu = IPV6_MIN_MTU;
768 }
769 dev->iflink = tunnel->parms.link;
770
771 return 0;
772}
773
774int __init ipip6_fb_tunnel_init(struct net_device *dev)
775{
776 struct ip_tunnel *tunnel = dev->priv;
777 struct iphdr *iph = &tunnel->parms.iph;
778
779 tunnel->dev = dev;
780 strcpy(tunnel->parms.name, dev->name);
781
782 iph->version = 4;
783 iph->protocol = IPPROTO_IPV6;
784 iph->ihl = 5;
785 iph->ttl = 64;
786
787 dev_hold(dev);
788 tunnels_wc[0] = tunnel;
789 return 0;
790}
791
792static struct net_protocol sit_protocol = {
793 .handler = ipip6_rcv,
794 .err_handler = ipip6_err,
795};
796
797void __exit sit_cleanup(void)
798{
799 inet_del_protocol(&sit_protocol, IPPROTO_IPV6);
800 unregister_netdev(ipip6_fb_tunnel_dev);
801}
802
803int __init sit_init(void)
804{
805 int err;
806
807 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
808
809 if (inet_add_protocol(&sit_protocol, IPPROTO_IPV6) < 0) {
810 printk(KERN_INFO "sit init: Can't add protocol\n");
811 return -EAGAIN;
812 }
813
814 ipip6_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
815 ipip6_tunnel_setup);
816 if (!ipip6_fb_tunnel_dev) {
817 err = -ENOMEM;
818 goto err1;
819 }
820
821 ipip6_fb_tunnel_dev->init = ipip6_fb_tunnel_init;
822
823 if ((err = register_netdev(ipip6_fb_tunnel_dev)))
824 goto err2;
825
826 out:
827 return err;
828 err2:
829 free_netdev(ipip6_fb_tunnel_dev);
830 err1:
831 inet_del_protocol(&sit_protocol, IPPROTO_IPV6);
832 goto out;
833}
Clone of davem's net-next-2.6 tree