[NET]: Nuke SET_MODULE_OWNER macro.
[linux-2.6.git] / net / ipv6 / ip6_tunnel.c
1 /*
2  *      IPv6 tunneling device
3  *      Linux INET6 implementation
4  *
5  *      Authors:
6  *      Ville Nuorvala          <vnuorval@tcs.hut.fi>
7  *      Yasuyuki Kozakai        <kozakai@linux-ipv6.org>
8  *
9  *      $Id$
10  *
11  *      Based on:
12  *      linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c
13  *
14  *      RFC 2473
15  *
16  *      This program is free software; you can redistribute it and/or
17  *      modify it under the terms of the GNU General Public License
18  *      as published by the Free Software Foundation; either version
19  *      2 of the License, or (at your option) any later version.
20  *
21  */
22
23 #include <linux/module.h>
24 #include <linux/capability.h>
25 #include <linux/errno.h>
26 #include <linux/types.h>
27 #include <linux/sockios.h>
28 #include <linux/icmp.h>
29 #include <linux/if.h>
30 #include <linux/in.h>
31 #include <linux/ip.h>
32 #include <linux/if_tunnel.h>
33 #include <linux/net.h>
34 #include <linux/in6.h>
35 #include <linux/netdevice.h>
36 #include <linux/if_arp.h>
37 #include <linux/icmpv6.h>
38 #include <linux/init.h>
39 #include <linux/route.h>
40 #include <linux/rtnetlink.h>
41 #include <linux/netfilter_ipv6.h>
42
43 #include <asm/uaccess.h>
44 #include <asm/atomic.h>
45
46 #include <net/icmp.h>
47 #include <net/ip.h>
48 #include <net/ipv6.h>
49 #include <net/ip6_route.h>
50 #include <net/addrconf.h>
51 #include <net/ip6_tunnel.h>
52 #include <net/xfrm.h>
53 #include <net/dsfield.h>
54 #include <net/inet_ecn.h>
55
56 MODULE_AUTHOR("Ville Nuorvala");
57 MODULE_DESCRIPTION("IPv6 tunneling device");
58 MODULE_LICENSE("GPL");
59
60 #define IPV6_TLV_TEL_DST_SIZE 8
61
62 #ifdef IP6_TNL_DEBUG
63 #define IP6_TNL_TRACE(x...) printk(KERN_DEBUG "%s:" x "\n", __FUNCTION__)
64 #else
65 #define IP6_TNL_TRACE(x...) do {;} while(0)
66 #endif
67
68 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
69 #define IPV6_TCLASS_SHIFT 20
70
71 #define HASH_SIZE  32
72
73 #define HASH(addr) ((__force u32)((addr)->s6_addr32[0] ^ (addr)->s6_addr32[1] ^ \
74                      (addr)->s6_addr32[2] ^ (addr)->s6_addr32[3]) & \
75                     (HASH_SIZE - 1))
76
77 static int ip6_fb_tnl_dev_init(struct net_device *dev);
78 static int ip6_tnl_dev_init(struct net_device *dev);
79 static void ip6_tnl_dev_setup(struct net_device *dev);
80
81 /* the IPv6 tunnel fallback device */
82 static struct net_device *ip6_fb_tnl_dev;
83
84
85 /* lists for storing tunnels in use */
86 static struct ip6_tnl *tnls_r_l[HASH_SIZE];
87 static struct ip6_tnl *tnls_wc[1];
88 static struct ip6_tnl **tnls[2] = { tnls_wc, tnls_r_l };
89
90 /* lock for the tunnel lists */
91 static DEFINE_RWLOCK(ip6_tnl_lock);
92
93 static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
94 {
95         struct dst_entry *dst = t->dst_cache;
96
97         if (dst && dst->obsolete &&
98             dst->ops->check(dst, t->dst_cookie) == NULL) {
99                 t->dst_cache = NULL;
100                 dst_release(dst);
101                 return NULL;
102         }
103
104         return dst;
105 }
106
107 static inline void ip6_tnl_dst_reset(struct ip6_tnl *t)
108 {
109         dst_release(t->dst_cache);
110         t->dst_cache = NULL;
111 }
112
113 static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
114 {
115         struct rt6_info *rt = (struct rt6_info *) dst;
116         t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
117         dst_release(t->dst_cache);
118         t->dst_cache = dst;
119 }
120
121 /**
122  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
123  *   @remote: the address of the tunnel exit-point
124  *   @local: the address of the tunnel entry-point
125  *
126  * Return:
127  *   tunnel matching given end-points if found,
128  *   else fallback tunnel if its device is up,
129  *   else %NULL
130  **/
131
132 static struct ip6_tnl *
133 ip6_tnl_lookup(struct in6_addr *remote, struct in6_addr *local)
134 {
135         unsigned h0 = HASH(remote);
136         unsigned h1 = HASH(local);
137         struct ip6_tnl *t;
138
139         for (t = tnls_r_l[h0 ^ h1]; t; t = t->next) {
140                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
141                     ipv6_addr_equal(remote, &t->parms.raddr) &&
142                     (t->dev->flags & IFF_UP))
143                         return t;
144         }
145         if ((t = tnls_wc[0]) != NULL && (t->dev->flags & IFF_UP))
146                 return t;
147
148         return NULL;
149 }
150
151 /**
152  * ip6_tnl_bucket - get head of list matching given tunnel parameters
153  *   @p: parameters containing tunnel end-points
154  *
155  * Description:
156  *   ip6_tnl_bucket() returns the head of the list matching the
157  *   &struct in6_addr entries laddr and raddr in @p.
158  *
159  * Return: head of IPv6 tunnel list
160  **/
161
162 static struct ip6_tnl **
163 ip6_tnl_bucket(struct ip6_tnl_parm *p)
164 {
165         struct in6_addr *remote = &p->raddr;
166         struct in6_addr *local = &p->laddr;
167         unsigned h = 0;
168         int prio = 0;
169
170         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
171                 prio = 1;
172                 h = HASH(remote) ^ HASH(local);
173         }
174         return &tnls[prio][h];
175 }
176
177 /**
178  * ip6_tnl_link - add tunnel to hash table
179  *   @t: tunnel to be added
180  **/
181
182 static void
183 ip6_tnl_link(struct ip6_tnl *t)
184 {
185         struct ip6_tnl **tp = ip6_tnl_bucket(&t->parms);
186
187         t->next = *tp;
188         write_lock_bh(&ip6_tnl_lock);
189         *tp = t;
190         write_unlock_bh(&ip6_tnl_lock);
191 }
192
193 /**
194  * ip6_tnl_unlink - remove tunnel from hash table
195  *   @t: tunnel to be removed
196  **/
197
198 static void
199 ip6_tnl_unlink(struct ip6_tnl *t)
200 {
201         struct ip6_tnl **tp;
202
203         for (tp = ip6_tnl_bucket(&t->parms); *tp; tp = &(*tp)->next) {
204                 if (t == *tp) {
205                         write_lock_bh(&ip6_tnl_lock);
206                         *tp = t->next;
207                         write_unlock_bh(&ip6_tnl_lock);
208                         break;
209                 }
210         }
211 }
212
213 /**
214  * ip6_tnl_create() - create a new tunnel
215  *   @p: tunnel parameters
216  *   @pt: pointer to new tunnel
217  *
218  * Description:
219  *   Create tunnel matching given parameters.
220  *
221  * Return:
222  *   created tunnel or NULL
223  **/
224
225 static struct ip6_tnl *ip6_tnl_create(struct ip6_tnl_parm *p)
226 {
227         struct net_device *dev;
228         struct ip6_tnl *t;
229         char name[IFNAMSIZ];
230         int err;
231
232         if (p->name[0]) {
233                 strlcpy(name, p->name, IFNAMSIZ);
234         } else {
235                 int i;
236                 for (i = 1; i < IP6_TNL_MAX; i++) {
237                         sprintf(name, "ip6tnl%d", i);
238                         if (__dev_get_by_name(&init_net, name) == NULL)
239                                 break;
240                 }
241                 if (i == IP6_TNL_MAX)
242                         goto failed;
243         }
244         dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup);
245         if (dev == NULL)
246                 goto failed;
247
248         t = netdev_priv(dev);
249         dev->init = ip6_tnl_dev_init;
250         t->parms = *p;
251
252         if ((err = register_netdevice(dev)) < 0) {
253                 free_netdev(dev);
254                 goto failed;
255         }
256         dev_hold(dev);
257         ip6_tnl_link(t);
258         return t;
259 failed:
260         return NULL;
261 }
262
263 /**
264  * ip6_tnl_locate - find or create tunnel matching given parameters
265  *   @p: tunnel parameters
266  *   @create: != 0 if allowed to create new tunnel if no match found
267  *
268  * Description:
269  *   ip6_tnl_locate() first tries to locate an existing tunnel
270  *   based on @parms. If this is unsuccessful, but @create is set a new
271  *   tunnel device is created and registered for use.
272  *
273  * Return:
274  *   matching tunnel or NULL
275  **/
276
277 static struct ip6_tnl *ip6_tnl_locate(struct ip6_tnl_parm *p, int create)
278 {
279         struct in6_addr *remote = &p->raddr;
280         struct in6_addr *local = &p->laddr;
281         struct ip6_tnl *t;
282
283         for (t = *ip6_tnl_bucket(p); t; t = t->next) {
284                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
285                     ipv6_addr_equal(remote, &t->parms.raddr))
286                         return t;
287         }
288         if (!create)
289                 return NULL;
290         return ip6_tnl_create(p);
291 }
292
293 /**
294  * ip6_tnl_dev_uninit - tunnel device uninitializer
295  *   @dev: the device to be destroyed
296  *
297  * Description:
298  *   ip6_tnl_dev_uninit() removes tunnel from its list
299  **/
300
301 static void
302 ip6_tnl_dev_uninit(struct net_device *dev)
303 {
304         struct ip6_tnl *t = netdev_priv(dev);
305
306         if (dev == ip6_fb_tnl_dev) {
307                 write_lock_bh(&ip6_tnl_lock);
308                 tnls_wc[0] = NULL;
309                 write_unlock_bh(&ip6_tnl_lock);
310         } else {
311                 ip6_tnl_unlink(t);
312         }
313         ip6_tnl_dst_reset(t);
314         dev_put(dev);
315 }
316
317 /**
318  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
319  *   @skb: received socket buffer
320  *
321  * Return:
322  *   0 if none was found,
323  *   else index to encapsulation limit
324  **/
325
326 static __u16
327 parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
328 {
329         struct ipv6hdr *ipv6h = (struct ipv6hdr *) raw;
330         __u8 nexthdr = ipv6h->nexthdr;
331         __u16 off = sizeof (*ipv6h);
332
333         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
334                 __u16 optlen = 0;
335                 struct ipv6_opt_hdr *hdr;
336                 if (raw + off + sizeof (*hdr) > skb->data &&
337                     !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
338                         break;
339
340                 hdr = (struct ipv6_opt_hdr *) (raw + off);
341                 if (nexthdr == NEXTHDR_FRAGMENT) {
342                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
343                         if (frag_hdr->frag_off)
344                                 break;
345                         optlen = 8;
346                 } else if (nexthdr == NEXTHDR_AUTH) {
347                         optlen = (hdr->hdrlen + 2) << 2;
348                 } else {
349                         optlen = ipv6_optlen(hdr);
350                 }
351                 if (nexthdr == NEXTHDR_DEST) {
352                         __u16 i = off + 2;
353                         while (1) {
354                                 struct ipv6_tlv_tnl_enc_lim *tel;
355
356                                 /* No more room for encapsulation limit */
357                                 if (i + sizeof (*tel) > off + optlen)
358                                         break;
359
360                                 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
361                                 /* return index of option if found and valid */
362                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
363                                     tel->length == 1)
364                                         return i;
365                                 /* else jump to next option */
366                                 if (tel->type)
367                                         i += tel->length + 2;
368                                 else
369                                         i++;
370                         }
371                 }
372                 nexthdr = hdr->nexthdr;
373                 off += optlen;
374         }
375         return 0;
376 }
377
378 /**
379  * ip6_tnl_err - tunnel error handler
380  *
381  * Description:
382  *   ip6_tnl_err() should handle errors in the tunnel according
383  *   to the specifications in RFC 2473.
384  **/
385
386 static int
387 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
388             int *type, int *code, int *msg, __u32 *info, int offset)
389 {
390         struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data;
391         struct ip6_tnl *t;
392         int rel_msg = 0;
393         int rel_type = ICMPV6_DEST_UNREACH;
394         int rel_code = ICMPV6_ADDR_UNREACH;
395         __u32 rel_info = 0;
396         __u16 len;
397         int err = -ENOENT;
398
399         /* If the packet doesn't contain the original IPv6 header we are
400            in trouble since we might need the source address for further
401            processing of the error. */
402
403         read_lock(&ip6_tnl_lock);
404         if ((t = ip6_tnl_lookup(&ipv6h->daddr, &ipv6h->saddr)) == NULL)
405                 goto out;
406
407         if (t->parms.proto != ipproto && t->parms.proto != 0)
408                 goto out;
409
410         err = 0;
411
412         switch (*type) {
413                 __u32 teli;
414                 struct ipv6_tlv_tnl_enc_lim *tel;
415                 __u32 mtu;
416         case ICMPV6_DEST_UNREACH:
417                 if (net_ratelimit())
418                         printk(KERN_WARNING
419                                "%s: Path to destination invalid "
420                                "or inactive!\n", t->parms.name);
421                 rel_msg = 1;
422                 break;
423         case ICMPV6_TIME_EXCEED:
424                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
425                         if (net_ratelimit())
426                                 printk(KERN_WARNING
427                                        "%s: Too small hop limit or "
428                                        "routing loop in tunnel!\n",
429                                        t->parms.name);
430                         rel_msg = 1;
431                 }
432                 break;
433         case ICMPV6_PARAMPROB:
434                 teli = 0;
435                 if ((*code) == ICMPV6_HDR_FIELD)
436                         teli = parse_tlv_tnl_enc_lim(skb, skb->data);
437
438                 if (teli && teli == *info - 2) {
439                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
440                         if (tel->encap_limit == 0) {
441                                 if (net_ratelimit())
442                                         printk(KERN_WARNING
443                                                "%s: Too small encapsulation "
444                                                "limit or routing loop in "
445                                                "tunnel!\n", t->parms.name);
446                                 rel_msg = 1;
447                         }
448                 } else if (net_ratelimit()) {
449                         printk(KERN_WARNING
450                                "%s: Recipient unable to parse tunneled "
451                                "packet!\n ", t->parms.name);
452                 }
453                 break;
454         case ICMPV6_PKT_TOOBIG:
455                 mtu = *info - offset;
456                 if (mtu < IPV6_MIN_MTU)
457                         mtu = IPV6_MIN_MTU;
458                 t->dev->mtu = mtu;
459
460                 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
461                         rel_type = ICMPV6_PKT_TOOBIG;
462                         rel_code = 0;
463                         rel_info = mtu;
464                         rel_msg = 1;
465                 }
466                 break;
467         }
468
469         *type = rel_type;
470         *code = rel_code;
471         *info = rel_info;
472         *msg = rel_msg;
473
474 out:
475         read_unlock(&ip6_tnl_lock);
476         return err;
477 }
478
479 static int
480 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
481            int type, int code, int offset, __be32 info)
482 {
483         int rel_msg = 0;
484         int rel_type = type;
485         int rel_code = code;
486         __u32 rel_info = ntohl(info);
487         int err;
488         struct sk_buff *skb2;
489         struct iphdr *eiph;
490         struct flowi fl;
491         struct rtable *rt;
492
493         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
494                           &rel_msg, &rel_info, offset);
495         if (err < 0)
496                 return err;
497
498         if (rel_msg == 0)
499                 return 0;
500
501         switch (rel_type) {
502         case ICMPV6_DEST_UNREACH:
503                 if (rel_code != ICMPV6_ADDR_UNREACH)
504                         return 0;
505                 rel_type = ICMP_DEST_UNREACH;
506                 rel_code = ICMP_HOST_UNREACH;
507                 break;
508         case ICMPV6_PKT_TOOBIG:
509                 if (rel_code != 0)
510                         return 0;
511                 rel_type = ICMP_DEST_UNREACH;
512                 rel_code = ICMP_FRAG_NEEDED;
513                 break;
514         default:
515                 return 0;
516         }
517
518         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
519                 return 0;
520
521         skb2 = skb_clone(skb, GFP_ATOMIC);
522         if (!skb2)
523                 return 0;
524
525         dst_release(skb2->dst);
526         skb2->dst = NULL;
527         skb_pull(skb2, offset);
528         skb_reset_network_header(skb2);
529         eiph = ip_hdr(skb2);
530
531         /* Try to guess incoming interface */
532         memset(&fl, 0, sizeof(fl));
533         fl.fl4_dst = eiph->saddr;
534         fl.fl4_tos = RT_TOS(eiph->tos);
535         fl.proto = IPPROTO_IPIP;
536         if (ip_route_output_key(&rt, &fl))
537                 goto out;
538
539         skb2->dev = rt->u.dst.dev;
540
541         /* route "incoming" packet */
542         if (rt->rt_flags & RTCF_LOCAL) {
543                 ip_rt_put(rt);
544                 rt = NULL;
545                 fl.fl4_dst = eiph->daddr;
546                 fl.fl4_src = eiph->saddr;
547                 fl.fl4_tos = eiph->tos;
548                 if (ip_route_output_key(&rt, &fl) ||
549                     rt->u.dst.dev->type != ARPHRD_TUNNEL) {
550                         ip_rt_put(rt);
551                         goto out;
552                 }
553         } else {
554                 ip_rt_put(rt);
555                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
556                                    skb2->dev) ||
557                     skb2->dst->dev->type != ARPHRD_TUNNEL)
558                         goto out;
559         }
560
561         /* change mtu on this route */
562         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
563                 if (rel_info > dst_mtu(skb2->dst))
564                         goto out;
565
566                 skb2->dst->ops->update_pmtu(skb2->dst, rel_info);
567         }
568
569         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
570
571 out:
572         kfree_skb(skb2);
573         return 0;
574 }
575
576 static int
577 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
578            int type, int code, int offset, __be32 info)
579 {
580         int rel_msg = 0;
581         int rel_type = type;
582         int rel_code = code;
583         __u32 rel_info = ntohl(info);
584         int err;
585
586         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
587                           &rel_msg, &rel_info, offset);
588         if (err < 0)
589                 return err;
590
591         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
592                 struct rt6_info *rt;
593                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
594
595                 if (!skb2)
596                         return 0;
597
598                 dst_release(skb2->dst);
599                 skb2->dst = NULL;
600                 skb_pull(skb2, offset);
601                 skb_reset_network_header(skb2);
602
603                 /* Try to guess incoming interface */
604                 rt = rt6_lookup(&ipv6_hdr(skb2)->saddr, NULL, 0, 0);
605
606                 if (rt && rt->rt6i_dev)
607                         skb2->dev = rt->rt6i_dev;
608
609                 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
610
611                 if (rt)
612                         dst_release(&rt->u.dst);
613
614                 kfree_skb(skb2);
615         }
616
617         return 0;
618 }
619
620 static void ip4ip6_dscp_ecn_decapsulate(struct ip6_tnl *t,
621                                         struct ipv6hdr *ipv6h,
622                                         struct sk_buff *skb)
623 {
624         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
625
626         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
627                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
628
629         if (INET_ECN_is_ce(dsfield))
630                 IP_ECN_set_ce(ip_hdr(skb));
631 }
632
633 static void ip6ip6_dscp_ecn_decapsulate(struct ip6_tnl *t,
634                                         struct ipv6hdr *ipv6h,
635                                         struct sk_buff *skb)
636 {
637         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
638                 ipv6_copy_dscp(ipv6h, ipv6_hdr(skb));
639
640         if (INET_ECN_is_ce(ipv6_get_dsfield(ipv6h)))
641                 IP6_ECN_set_ce(ipv6_hdr(skb));
642 }
643
644 static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t)
645 {
646         struct ip6_tnl_parm *p = &t->parms;
647         int ret = 0;
648
649         if (p->flags & IP6_TNL_F_CAP_RCV) {
650                 struct net_device *ldev = NULL;
651
652                 if (p->link)
653                         ldev = dev_get_by_index(&init_net, p->link);
654
655                 if ((ipv6_addr_is_multicast(&p->laddr) ||
656                      likely(ipv6_chk_addr(&p->laddr, ldev, 0))) &&
657                     likely(!ipv6_chk_addr(&p->raddr, NULL, 0)))
658                         ret = 1;
659
660                 if (ldev)
661                         dev_put(ldev);
662         }
663         return ret;
664 }
665
666 /**
667  * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
668  *   @skb: received socket buffer
669  *   @protocol: ethernet protocol ID
670  *   @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN
671  *
672  * Return: 0
673  **/
674
675 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
676                        __u8 ipproto,
677                        void (*dscp_ecn_decapsulate)(struct ip6_tnl *t,
678                                                     struct ipv6hdr *ipv6h,
679                                                     struct sk_buff *skb))
680 {
681         struct ip6_tnl *t;
682         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
683
684         read_lock(&ip6_tnl_lock);
685
686         if ((t = ip6_tnl_lookup(&ipv6h->saddr, &ipv6h->daddr)) != NULL) {
687                 if (t->parms.proto != ipproto && t->parms.proto != 0) {
688                         read_unlock(&ip6_tnl_lock);
689                         goto discard;
690                 }
691
692                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
693                         read_unlock(&ip6_tnl_lock);
694                         goto discard;
695                 }
696
697                 if (!ip6_tnl_rcv_ctl(t)) {
698                         t->stat.rx_dropped++;
699                         read_unlock(&ip6_tnl_lock);
700                         goto discard;
701                 }
702                 secpath_reset(skb);
703                 skb->mac_header = skb->network_header;
704                 skb_reset_network_header(skb);
705                 skb->protocol = htons(protocol);
706                 skb->pkt_type = PACKET_HOST;
707                 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
708                 skb->dev = t->dev;
709                 dst_release(skb->dst);
710                 skb->dst = NULL;
711                 nf_reset(skb);
712
713                 dscp_ecn_decapsulate(t, ipv6h, skb);
714
715                 t->stat.rx_packets++;
716                 t->stat.rx_bytes += skb->len;
717                 netif_rx(skb);
718                 read_unlock(&ip6_tnl_lock);
719                 return 0;
720         }
721         read_unlock(&ip6_tnl_lock);
722         return 1;
723
724 discard:
725         kfree_skb(skb);
726         return 0;
727 }
728
729 static int ip4ip6_rcv(struct sk_buff *skb)
730 {
731         return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
732                            ip4ip6_dscp_ecn_decapsulate);
733 }
734
735 static int ip6ip6_rcv(struct sk_buff *skb)
736 {
737         return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
738                            ip6ip6_dscp_ecn_decapsulate);
739 }
740
741 struct ipv6_tel_txoption {
742         struct ipv6_txoptions ops;
743         __u8 dst_opt[8];
744 };
745
746 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
747 {
748         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
749
750         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
751         opt->dst_opt[3] = 1;
752         opt->dst_opt[4] = encap_limit;
753         opt->dst_opt[5] = IPV6_TLV_PADN;
754         opt->dst_opt[6] = 1;
755
756         opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
757         opt->ops.opt_nflen = 8;
758 }
759
760 /**
761  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
762  *   @t: the outgoing tunnel device
763  *   @hdr: IPv6 header from the incoming packet
764  *
765  * Description:
766  *   Avoid trivial tunneling loop by checking that tunnel exit-point
767  *   doesn't match source of incoming packet.
768  *
769  * Return:
770  *   1 if conflict,
771  *   0 else
772  **/
773
774 static inline int
775 ip6_tnl_addr_conflict(struct ip6_tnl *t, struct ipv6hdr *hdr)
776 {
777         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
778 }
779
780 static inline int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
781 {
782         struct ip6_tnl_parm *p = &t->parms;
783         int ret = 0;
784
785         if (p->flags & IP6_TNL_F_CAP_XMIT) {
786                 struct net_device *ldev = NULL;
787
788                 if (p->link)
789                         ldev = dev_get_by_index(&init_net, p->link);
790
791                 if (unlikely(!ipv6_chk_addr(&p->laddr, ldev, 0)))
792                         printk(KERN_WARNING
793                                "%s xmit: Local address not yet configured!\n",
794                                p->name);
795                 else if (!ipv6_addr_is_multicast(&p->raddr) &&
796                          unlikely(ipv6_chk_addr(&p->raddr, NULL, 0)))
797                         printk(KERN_WARNING
798                                "%s xmit: Routing loop! "
799                                "Remote address found on this node!\n",
800                                p->name);
801                 else
802                         ret = 1;
803                 if (ldev)
804                         dev_put(ldev);
805         }
806         return ret;
807 }
808 /**
809  * ip6_tnl_xmit2 - encapsulate packet and send
810  *   @skb: the outgoing socket buffer
811  *   @dev: the outgoing tunnel device
812  *   @dsfield: dscp code for outer header
813  *   @fl: flow of tunneled packet
814  *   @encap_limit: encapsulation limit
815  *   @pmtu: Path MTU is stored if packet is too big
816  *
817  * Description:
818  *   Build new header and do some sanity checks on the packet before sending
819  *   it.
820  *
821  * Return:
822  *   0 on success
823  *   -1 fail
824  *   %-EMSGSIZE message too big. return mtu in this case.
825  **/
826
827 static int ip6_tnl_xmit2(struct sk_buff *skb,
828                          struct net_device *dev,
829                          __u8 dsfield,
830                          struct flowi *fl,
831                          int encap_limit,
832                          __u32 *pmtu)
833 {
834         struct ip6_tnl *t = netdev_priv(dev);
835         struct net_device_stats *stats = &t->stat;
836         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
837         struct ipv6_tel_txoption opt;
838         struct dst_entry *dst;
839         struct net_device *tdev;
840         int mtu;
841         int max_headroom = sizeof(struct ipv6hdr);
842         u8 proto;
843         int err = -1;
844         int pkt_len;
845
846         if ((dst = ip6_tnl_dst_check(t)) != NULL)
847                 dst_hold(dst);
848         else {
849                 dst = ip6_route_output(NULL, fl);
850
851                 if (dst->error || xfrm_lookup(&dst, fl, NULL, 0) < 0)
852                         goto tx_err_link_failure;
853         }
854
855         tdev = dst->dev;
856
857         if (tdev == dev) {
858                 stats->collisions++;
859                 if (net_ratelimit())
860                         printk(KERN_WARNING
861                                "%s: Local routing loop detected!\n",
862                                t->parms.name);
863                 goto tx_err_dst_release;
864         }
865         mtu = dst_mtu(dst) - sizeof (*ipv6h);
866         if (encap_limit >= 0) {
867                 max_headroom += 8;
868                 mtu -= 8;
869         }
870         if (mtu < IPV6_MIN_MTU)
871                 mtu = IPV6_MIN_MTU;
872         if (skb->dst)
873                 skb->dst->ops->update_pmtu(skb->dst, mtu);
874         if (skb->len > mtu) {
875                 *pmtu = mtu;
876                 err = -EMSGSIZE;
877                 goto tx_err_dst_release;
878         }
879
880         /*
881          * Okay, now see if we can stuff it in the buffer as-is.
882          */
883         max_headroom += LL_RESERVED_SPACE(tdev);
884
885         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
886             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
887                 struct sk_buff *new_skb;
888
889                 if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
890                         goto tx_err_dst_release;
891
892                 if (skb->sk)
893                         skb_set_owner_w(new_skb, skb->sk);
894                 kfree_skb(skb);
895                 skb = new_skb;
896         }
897         dst_release(skb->dst);
898         skb->dst = dst_clone(dst);
899
900         skb->transport_header = skb->network_header;
901
902         proto = fl->proto;
903         if (encap_limit >= 0) {
904                 init_tel_txopt(&opt, encap_limit);
905                 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
906         }
907         skb_push(skb, sizeof(struct ipv6hdr));
908         skb_reset_network_header(skb);
909         ipv6h = ipv6_hdr(skb);
910         *(__be32*)ipv6h = fl->fl6_flowlabel | htonl(0x60000000);
911         dsfield = INET_ECN_encapsulate(0, dsfield);
912         ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
913         ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
914         ipv6h->hop_limit = t->parms.hop_limit;
915         ipv6h->nexthdr = proto;
916         ipv6_addr_copy(&ipv6h->saddr, &fl->fl6_src);
917         ipv6_addr_copy(&ipv6h->daddr, &fl->fl6_dst);
918         nf_reset(skb);
919         pkt_len = skb->len;
920         err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL,
921                       skb->dst->dev, dst_output);
922
923         if (net_xmit_eval(err) == 0) {
924                 stats->tx_bytes += pkt_len;
925                 stats->tx_packets++;
926         } else {
927                 stats->tx_errors++;
928                 stats->tx_aborted_errors++;
929         }
930         ip6_tnl_dst_store(t, dst);
931         return 0;
932 tx_err_link_failure:
933         stats->tx_carrier_errors++;
934         dst_link_failure(skb);
935 tx_err_dst_release:
936         dst_release(dst);
937         return err;
938 }
939
940 static inline int
941 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
942 {
943         struct ip6_tnl *t = netdev_priv(dev);
944         struct iphdr  *iph = ip_hdr(skb);
945         int encap_limit = -1;
946         struct flowi fl;
947         __u8 dsfield;
948         __u32 mtu;
949         int err;
950
951         if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) ||
952             !ip6_tnl_xmit_ctl(t))
953                 return -1;
954
955         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
956                 encap_limit = t->parms.encap_limit;
957
958         memcpy(&fl, &t->fl, sizeof (fl));
959         fl.proto = IPPROTO_IPIP;
960
961         dsfield = ipv4_get_dsfield(iph);
962
963         if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS))
964                 fl.fl6_flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
965                                           & IPV6_TCLASS_MASK;
966
967         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu);
968         if (err != 0) {
969                 /* XXX: send ICMP error even if DF is not set. */
970                 if (err == -EMSGSIZE)
971                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
972                                   htonl(mtu));
973                 return -1;
974         }
975
976         return 0;
977 }
978
979 static inline int
980 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
981 {
982         struct ip6_tnl *t = netdev_priv(dev);
983         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
984         int encap_limit = -1;
985         __u16 offset;
986         struct flowi fl;
987         __u8 dsfield;
988         __u32 mtu;
989         int err;
990
991         if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
992             !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
993                 return -1;
994
995         offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb));
996         if (offset > 0) {
997                 struct ipv6_tlv_tnl_enc_lim *tel;
998                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
999                 if (tel->encap_limit == 0) {
1000                         icmpv6_send(skb, ICMPV6_PARAMPROB,
1001                                     ICMPV6_HDR_FIELD, offset + 2, skb->dev);
1002                         return -1;
1003                 }
1004                 encap_limit = tel->encap_limit - 1;
1005         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1006                 encap_limit = t->parms.encap_limit;
1007
1008         memcpy(&fl, &t->fl, sizeof (fl));
1009         fl.proto = IPPROTO_IPV6;
1010
1011         dsfield = ipv6_get_dsfield(ipv6h);
1012         if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS))
1013                 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1014         if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL))
1015                 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
1016
1017         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl, encap_limit, &mtu);
1018         if (err != 0) {
1019                 if (err == -EMSGSIZE)
1020                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
1021                 return -1;
1022         }
1023
1024         return 0;
1025 }
1026
1027 static int
1028 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1029 {
1030         struct ip6_tnl *t = netdev_priv(dev);
1031         struct net_device_stats *stats = &t->stat;
1032         int ret;
1033
1034         if (t->recursion++) {
1035                 t->stat.collisions++;
1036                 goto tx_err;
1037         }
1038
1039         switch (skb->protocol) {
1040         case __constant_htons(ETH_P_IP):
1041                 ret = ip4ip6_tnl_xmit(skb, dev);
1042                 break;
1043         case __constant_htons(ETH_P_IPV6):
1044                 ret = ip6ip6_tnl_xmit(skb, dev);
1045                 break;
1046         default:
1047                 goto tx_err;
1048         }
1049
1050         if (ret < 0)
1051                 goto tx_err;
1052
1053         t->recursion--;
1054         return 0;
1055
1056 tx_err:
1057         stats->tx_errors++;
1058         stats->tx_dropped++;
1059         kfree_skb(skb);
1060         t->recursion--;
1061         return 0;
1062 }
1063
1064 static void ip6_tnl_set_cap(struct ip6_tnl *t)
1065 {
1066         struct ip6_tnl_parm *p = &t->parms;
1067         int ltype = ipv6_addr_type(&p->laddr);
1068         int rtype = ipv6_addr_type(&p->raddr);
1069
1070         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV);
1071
1072         if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
1073             rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
1074             !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
1075             (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
1076                 if (ltype&IPV6_ADDR_UNICAST)
1077                         p->flags |= IP6_TNL_F_CAP_XMIT;
1078                 if (rtype&IPV6_ADDR_UNICAST)
1079                         p->flags |= IP6_TNL_F_CAP_RCV;
1080         }
1081 }
1082
1083 static void ip6_tnl_link_config(struct ip6_tnl *t)
1084 {
1085         struct net_device *dev = t->dev;
1086         struct ip6_tnl_parm *p = &t->parms;
1087         struct flowi *fl = &t->fl;
1088
1089         memcpy(&dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1090         memcpy(&dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1091
1092         /* Set up flowi template */
1093         ipv6_addr_copy(&fl->fl6_src, &p->laddr);
1094         ipv6_addr_copy(&fl->fl6_dst, &p->raddr);
1095         fl->oif = p->link;
1096         fl->fl6_flowlabel = 0;
1097
1098         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1099                 fl->fl6_flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1100         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1101                 fl->fl6_flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1102
1103         ip6_tnl_set_cap(t);
1104
1105         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1106                 dev->flags |= IFF_POINTOPOINT;
1107         else
1108                 dev->flags &= ~IFF_POINTOPOINT;
1109
1110         dev->iflink = p->link;
1111
1112         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1113                 int strict = (ipv6_addr_type(&p->raddr) &
1114                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1115
1116                 struct rt6_info *rt = rt6_lookup(&p->raddr, &p->laddr,
1117                                                  p->link, strict);
1118
1119                 if (rt == NULL)
1120                         return;
1121
1122                 if (rt->rt6i_dev) {
1123                         dev->hard_header_len = rt->rt6i_dev->hard_header_len +
1124                                 sizeof (struct ipv6hdr);
1125
1126                         dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr);
1127
1128                         if (dev->mtu < IPV6_MIN_MTU)
1129                                 dev->mtu = IPV6_MIN_MTU;
1130                 }
1131                 dst_release(&rt->u.dst);
1132         }
1133 }
1134
1135 /**
1136  * ip6_tnl_change - update the tunnel parameters
1137  *   @t: tunnel to be changed
1138  *   @p: tunnel configuration parameters
1139  *   @active: != 0 if tunnel is ready for use
1140  *
1141  * Description:
1142  *   ip6_tnl_change() updates the tunnel parameters
1143  **/
1144
1145 static int
1146 ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p)
1147 {
1148         ipv6_addr_copy(&t->parms.laddr, &p->laddr);
1149         ipv6_addr_copy(&t->parms.raddr, &p->raddr);
1150         t->parms.flags = p->flags;
1151         t->parms.hop_limit = p->hop_limit;
1152         t->parms.encap_limit = p->encap_limit;
1153         t->parms.flowinfo = p->flowinfo;
1154         t->parms.link = p->link;
1155         t->parms.proto = p->proto;
1156         ip6_tnl_dst_reset(t);
1157         ip6_tnl_link_config(t);
1158         return 0;
1159 }
1160
1161 /**
1162  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1163  *   @dev: virtual device associated with tunnel
1164  *   @ifr: parameters passed from userspace
1165  *   @cmd: command to be performed
1166  *
1167  * Description:
1168  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1169  *   from userspace.
1170  *
1171  *   The possible commands are the following:
1172  *     %SIOCGETTUNNEL: get tunnel parameters for device
1173  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1174  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1175  *     %SIOCDELTUNNEL: delete tunnel
1176  *
1177  *   The fallback device "ip6tnl0", created during module
1178  *   initialization, can be used for creating other tunnel devices.
1179  *
1180  * Return:
1181  *   0 on success,
1182  *   %-EFAULT if unable to copy data to or from userspace,
1183  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1184  *   %-EINVAL if passed tunnel parameters are invalid,
1185  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1186  *   %-ENODEV if attempting to change or delete a nonexisting device
1187  **/
1188
1189 static int
1190 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1191 {
1192         int err = 0;
1193         struct ip6_tnl_parm p;
1194         struct ip6_tnl *t = NULL;
1195
1196         switch (cmd) {
1197         case SIOCGETTUNNEL:
1198                 if (dev == ip6_fb_tnl_dev) {
1199                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {
1200                                 err = -EFAULT;
1201                                 break;
1202                         }
1203                         t = ip6_tnl_locate(&p, 0);
1204                 }
1205                 if (t == NULL)
1206                         t = netdev_priv(dev);
1207                 memcpy(&p, &t->parms, sizeof (p));
1208                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
1209                         err = -EFAULT;
1210                 }
1211                 break;
1212         case SIOCADDTUNNEL:
1213         case SIOCCHGTUNNEL:
1214                 err = -EPERM;
1215                 if (!capable(CAP_NET_ADMIN))
1216                         break;
1217                 err = -EFAULT;
1218                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1219                         break;
1220                 err = -EINVAL;
1221                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1222                     p.proto != 0)
1223                         break;
1224                 t = ip6_tnl_locate(&p, cmd == SIOCADDTUNNEL);
1225                 if (dev != ip6_fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
1226                         if (t != NULL) {
1227                                 if (t->dev != dev) {
1228                                         err = -EEXIST;
1229                                         break;
1230                                 }
1231                         } else
1232                                 t = netdev_priv(dev);
1233
1234                         ip6_tnl_unlink(t);
1235                         err = ip6_tnl_change(t, &p);
1236                         ip6_tnl_link(t);
1237                         netdev_state_change(dev);
1238                 }
1239                 if (t) {
1240                         err = 0;
1241                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p)))
1242                                 err = -EFAULT;
1243
1244                 } else
1245                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1246                 break;
1247         case SIOCDELTUNNEL:
1248                 err = -EPERM;
1249                 if (!capable(CAP_NET_ADMIN))
1250                         break;
1251
1252                 if (dev == ip6_fb_tnl_dev) {
1253                         err = -EFAULT;
1254                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1255                                 break;
1256                         err = -ENOENT;
1257                         if ((t = ip6_tnl_locate(&p, 0)) == NULL)
1258                                 break;
1259                         err = -EPERM;
1260                         if (t->dev == ip6_fb_tnl_dev)
1261                                 break;
1262                         dev = t->dev;
1263                 }
1264                 err = 0;
1265                 unregister_netdevice(dev);
1266                 break;
1267         default:
1268                 err = -EINVAL;
1269         }
1270         return err;
1271 }
1272
1273 /**
1274  * ip6_tnl_get_stats - return the stats for tunnel device
1275  *   @dev: virtual device associated with tunnel
1276  *
1277  * Return: stats for device
1278  **/
1279
1280 static struct net_device_stats *
1281 ip6_tnl_get_stats(struct net_device *dev)
1282 {
1283         return &(((struct ip6_tnl *)netdev_priv(dev))->stat);
1284 }
1285
1286 /**
1287  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1288  *   @dev: virtual device associated with tunnel
1289  *   @new_mtu: the new mtu
1290  *
1291  * Return:
1292  *   0 on success,
1293  *   %-EINVAL if mtu too small
1294  **/
1295
1296 static int
1297 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1298 {
1299         if (new_mtu < IPV6_MIN_MTU) {
1300                 return -EINVAL;
1301         }
1302         dev->mtu = new_mtu;
1303         return 0;
1304 }
1305
1306 /**
1307  * ip6_tnl_dev_setup - setup virtual tunnel device
1308  *   @dev: virtual device associated with tunnel
1309  *
1310  * Description:
1311  *   Initialize function pointers and device parameters
1312  **/
1313
1314 static void ip6_tnl_dev_setup(struct net_device *dev)
1315 {
1316         dev->uninit = ip6_tnl_dev_uninit;
1317         dev->destructor = free_netdev;
1318         dev->hard_start_xmit = ip6_tnl_xmit;
1319         dev->get_stats = ip6_tnl_get_stats;
1320         dev->do_ioctl = ip6_tnl_ioctl;
1321         dev->change_mtu = ip6_tnl_change_mtu;
1322
1323         dev->type = ARPHRD_TUNNEL6;
1324         dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
1325         dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr);
1326         dev->flags |= IFF_NOARP;
1327         dev->addr_len = sizeof(struct in6_addr);
1328 }
1329
1330
1331 /**
1332  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1333  *   @dev: virtual device associated with tunnel
1334  **/
1335
1336 static inline void
1337 ip6_tnl_dev_init_gen(struct net_device *dev)
1338 {
1339         struct ip6_tnl *t = netdev_priv(dev);
1340         t->dev = dev;
1341         strcpy(t->parms.name, dev->name);
1342 }
1343
1344 /**
1345  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1346  *   @dev: virtual device associated with tunnel
1347  **/
1348
1349 static int
1350 ip6_tnl_dev_init(struct net_device *dev)
1351 {
1352         struct ip6_tnl *t = netdev_priv(dev);
1353         ip6_tnl_dev_init_gen(dev);
1354         ip6_tnl_link_config(t);
1355         return 0;
1356 }
1357
1358 /**
1359  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1360  *   @dev: fallback device
1361  *
1362  * Return: 0
1363  **/
1364
1365 static int
1366 ip6_fb_tnl_dev_init(struct net_device *dev)
1367 {
1368         struct ip6_tnl *t = netdev_priv(dev);
1369         ip6_tnl_dev_init_gen(dev);
1370         t->parms.proto = IPPROTO_IPV6;
1371         dev_hold(dev);
1372         tnls_wc[0] = t;
1373         return 0;
1374 }
1375
1376 static struct xfrm6_tunnel ip4ip6_handler = {
1377         .handler        = ip4ip6_rcv,
1378         .err_handler    = ip4ip6_err,
1379         .priority       =       1,
1380 };
1381
1382 static struct xfrm6_tunnel ip6ip6_handler = {
1383         .handler        = ip6ip6_rcv,
1384         .err_handler    = ip6ip6_err,
1385         .priority       =       1,
1386 };
1387
1388 /**
1389  * ip6_tunnel_init - register protocol and reserve needed resources
1390  *
1391  * Return: 0 on success
1392  **/
1393
1394 static int __init ip6_tunnel_init(void)
1395 {
1396         int  err;
1397
1398         if (xfrm6_tunnel_register(&ip4ip6_handler, AF_INET)) {
1399                 printk(KERN_ERR "ip6_tunnel init: can't register ip4ip6\n");
1400                 err = -EAGAIN;
1401                 goto out;
1402         }
1403
1404         if (xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6)) {
1405                 printk(KERN_ERR "ip6_tunnel init: can't register ip6ip6\n");
1406                 err = -EAGAIN;
1407                 goto unreg_ip4ip6;
1408         }
1409         ip6_fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1410                                       ip6_tnl_dev_setup);
1411
1412         if (!ip6_fb_tnl_dev) {
1413                 err = -ENOMEM;
1414                 goto fail;
1415         }
1416         ip6_fb_tnl_dev->init = ip6_fb_tnl_dev_init;
1417
1418         if ((err = register_netdev(ip6_fb_tnl_dev))) {
1419                 free_netdev(ip6_fb_tnl_dev);
1420                 goto fail;
1421         }
1422         return 0;
1423 fail:
1424         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
1425 unreg_ip4ip6:
1426         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1427 out:
1428         return err;
1429 }
1430
1431 static void __exit ip6_tnl_destroy_tunnels(void)
1432 {
1433         int h;
1434         struct ip6_tnl *t;
1435
1436         for (h = 0; h < HASH_SIZE; h++) {
1437                 while ((t = tnls_r_l[h]) != NULL)
1438                         unregister_netdevice(t->dev);
1439         }
1440
1441         t = tnls_wc[0];
1442         unregister_netdevice(t->dev);
1443 }
1444
1445 /**
1446  * ip6_tunnel_cleanup - free resources and unregister protocol
1447  **/
1448
1449 static void __exit ip6_tunnel_cleanup(void)
1450 {
1451         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1452                 printk(KERN_INFO "ip6_tunnel close: can't deregister ip4ip6\n");
1453
1454         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
1455                 printk(KERN_INFO "ip6_tunnel close: can't deregister ip6ip6\n");
1456
1457         rtnl_lock();
1458         ip6_tnl_destroy_tunnels();
1459         rtnl_unlock();
1460 }
1461
1462 module_init(ip6_tunnel_init);
1463 module_exit(ip6_tunnel_cleanup);