Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso...
[cascardo/linux.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  *      Based on:
10  *      linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c
11  *
12  *      RFC 2473
13  *
14  *      This program is free software; you can redistribute it and/or
15  *      modify it under the terms of the GNU General Public License
16  *      as published by the Free Software Foundation; either version
17  *      2 of the License, or (at your option) any later version.
18  *
19  */
20
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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/net.h>
33 #include <linux/in6.h>
34 #include <linux/netdevice.h>
35 #include <linux/if_arp.h>
36 #include <linux/icmpv6.h>
37 #include <linux/init.h>
38 #include <linux/route.h>
39 #include <linux/rtnetlink.h>
40 #include <linux/netfilter_ipv6.h>
41 #include <linux/slab.h>
42 #include <linux/hash.h>
43 #include <linux/etherdevice.h>
44
45 #include <asm/uaccess.h>
46 #include <linux/atomic.h>
47
48 #include <net/icmp.h>
49 #include <net/ip.h>
50 #include <net/ip_tunnels.h>
51 #include <net/ipv6.h>
52 #include <net/ip6_route.h>
53 #include <net/addrconf.h>
54 #include <net/ip6_tunnel.h>
55 #include <net/xfrm.h>
56 #include <net/dsfield.h>
57 #include <net/inet_ecn.h>
58 #include <net/net_namespace.h>
59 #include <net/netns/generic.h>
60
61 MODULE_AUTHOR("Ville Nuorvala");
62 MODULE_DESCRIPTION("IPv6 tunneling device");
63 MODULE_LICENSE("GPL");
64 MODULE_ALIAS_RTNL_LINK("ip6tnl");
65 MODULE_ALIAS_NETDEV("ip6tnl0");
66
67 #ifdef IP6_TNL_DEBUG
68 #define IP6_TNL_TRACE(x...) pr_debug("%s:" x "\n", __func__)
69 #else
70 #define IP6_TNL_TRACE(x...) do {;} while(0)
71 #endif
72
73 #define HASH_SIZE_SHIFT  5
74 #define HASH_SIZE (1 << HASH_SIZE_SHIFT)
75
76 static bool log_ecn_error = true;
77 module_param(log_ecn_error, bool, 0644);
78 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
79
80 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
81 {
82         u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
83
84         return hash_32(hash, HASH_SIZE_SHIFT);
85 }
86
87 static int ip6_tnl_dev_init(struct net_device *dev);
88 static void ip6_tnl_dev_setup(struct net_device *dev);
89 static struct rtnl_link_ops ip6_link_ops __read_mostly;
90
91 static int ip6_tnl_net_id __read_mostly;
92 struct ip6_tnl_net {
93         /* the IPv6 tunnel fallback device */
94         struct net_device *fb_tnl_dev;
95         /* lists for storing tunnels in use */
96         struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
97         struct ip6_tnl __rcu *tnls_wc[1];
98         struct ip6_tnl __rcu **tnls[2];
99 };
100
101 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
102 {
103         struct pcpu_sw_netstats tmp, sum = { 0 };
104         int i;
105
106         for_each_possible_cpu(i) {
107                 unsigned int start;
108                 const struct pcpu_sw_netstats *tstats =
109                                                    per_cpu_ptr(dev->tstats, i);
110
111                 do {
112                         start = u64_stats_fetch_begin_irq(&tstats->syncp);
113                         tmp.rx_packets = tstats->rx_packets;
114                         tmp.rx_bytes = tstats->rx_bytes;
115                         tmp.tx_packets = tstats->tx_packets;
116                         tmp.tx_bytes =  tstats->tx_bytes;
117                 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start));
118
119                 sum.rx_packets += tmp.rx_packets;
120                 sum.rx_bytes   += tmp.rx_bytes;
121                 sum.tx_packets += tmp.tx_packets;
122                 sum.tx_bytes   += tmp.tx_bytes;
123         }
124         dev->stats.rx_packets = sum.rx_packets;
125         dev->stats.rx_bytes   = sum.rx_bytes;
126         dev->stats.tx_packets = sum.tx_packets;
127         dev->stats.tx_bytes   = sum.tx_bytes;
128         return &dev->stats;
129 }
130
131 /*
132  * Locking : hash tables are protected by RCU and RTNL
133  */
134
135 struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
136 {
137         struct dst_entry *dst = t->dst_cache;
138
139         if (dst && dst->obsolete &&
140             dst->ops->check(dst, t->dst_cookie) == NULL) {
141                 t->dst_cache = NULL;
142                 dst_release(dst);
143                 return NULL;
144         }
145
146         return dst;
147 }
148 EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
149
150 void ip6_tnl_dst_reset(struct ip6_tnl *t)
151 {
152         dst_release(t->dst_cache);
153         t->dst_cache = NULL;
154 }
155 EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
156
157 void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
158 {
159         struct rt6_info *rt = (struct rt6_info *) dst;
160         t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
161         dst_release(t->dst_cache);
162         t->dst_cache = dst;
163 }
164 EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
165
166 /**
167  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
168  *   @remote: the address of the tunnel exit-point
169  *   @local: the address of the tunnel entry-point
170  *
171  * Return:
172  *   tunnel matching given end-points if found,
173  *   else fallback tunnel if its device is up,
174  *   else %NULL
175  **/
176
177 #define for_each_ip6_tunnel_rcu(start) \
178         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
179
180 static struct ip6_tnl *
181 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
182 {
183         unsigned int hash = HASH(remote, local);
184         struct ip6_tnl *t;
185         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
186         struct in6_addr any;
187
188         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
189                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
190                     ipv6_addr_equal(remote, &t->parms.raddr) &&
191                     (t->dev->flags & IFF_UP))
192                         return t;
193         }
194
195         memset(&any, 0, sizeof(any));
196         hash = HASH(&any, local);
197         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
198                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
199                     (t->dev->flags & IFF_UP))
200                         return t;
201         }
202
203         hash = HASH(remote, &any);
204         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
205                 if (ipv6_addr_equal(remote, &t->parms.raddr) &&
206                     (t->dev->flags & IFF_UP))
207                         return t;
208         }
209
210         t = rcu_dereference(ip6n->tnls_wc[0]);
211         if (t && (t->dev->flags & IFF_UP))
212                 return t;
213
214         return NULL;
215 }
216
217 /**
218  * ip6_tnl_bucket - get head of list matching given tunnel parameters
219  *   @p: parameters containing tunnel end-points
220  *
221  * Description:
222  *   ip6_tnl_bucket() returns the head of the list matching the
223  *   &struct in6_addr entries laddr and raddr in @p.
224  *
225  * Return: head of IPv6 tunnel list
226  **/
227
228 static struct ip6_tnl __rcu **
229 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
230 {
231         const struct in6_addr *remote = &p->raddr;
232         const struct in6_addr *local = &p->laddr;
233         unsigned int h = 0;
234         int prio = 0;
235
236         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
237                 prio = 1;
238                 h = HASH(remote, local);
239         }
240         return &ip6n->tnls[prio][h];
241 }
242
243 /**
244  * ip6_tnl_link - add tunnel to hash table
245  *   @t: tunnel to be added
246  **/
247
248 static void
249 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
250 {
251         struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
252
253         rcu_assign_pointer(t->next , rtnl_dereference(*tp));
254         rcu_assign_pointer(*tp, t);
255 }
256
257 /**
258  * ip6_tnl_unlink - remove tunnel from hash table
259  *   @t: tunnel to be removed
260  **/
261
262 static void
263 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
264 {
265         struct ip6_tnl __rcu **tp;
266         struct ip6_tnl *iter;
267
268         for (tp = ip6_tnl_bucket(ip6n, &t->parms);
269              (iter = rtnl_dereference(*tp)) != NULL;
270              tp = &iter->next) {
271                 if (t == iter) {
272                         rcu_assign_pointer(*tp, t->next);
273                         break;
274                 }
275         }
276 }
277
278 static void ip6_dev_free(struct net_device *dev)
279 {
280         free_percpu(dev->tstats);
281         free_netdev(dev);
282 }
283
284 static int ip6_tnl_create2(struct net_device *dev)
285 {
286         struct ip6_tnl *t = netdev_priv(dev);
287         struct net *net = dev_net(dev);
288         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
289         int err;
290
291         t = netdev_priv(dev);
292
293         err = register_netdevice(dev);
294         if (err < 0)
295                 goto out;
296
297         strcpy(t->parms.name, dev->name);
298         dev->rtnl_link_ops = &ip6_link_ops;
299
300         dev_hold(dev);
301         ip6_tnl_link(ip6n, t);
302         return 0;
303
304 out:
305         return err;
306 }
307
308 /**
309  * ip6_tnl_create - create a new tunnel
310  *   @p: tunnel parameters
311  *   @pt: pointer to new tunnel
312  *
313  * Description:
314  *   Create tunnel matching given parameters.
315  *
316  * Return:
317  *   created tunnel or NULL
318  **/
319
320 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
321 {
322         struct net_device *dev;
323         struct ip6_tnl *t;
324         char name[IFNAMSIZ];
325         int err;
326
327         if (p->name[0])
328                 strlcpy(name, p->name, IFNAMSIZ);
329         else
330                 sprintf(name, "ip6tnl%%d");
331
332         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
333                            ip6_tnl_dev_setup);
334         if (dev == NULL)
335                 goto failed;
336
337         dev_net_set(dev, net);
338
339         t = netdev_priv(dev);
340         t->parms = *p;
341         t->net = dev_net(dev);
342         err = ip6_tnl_create2(dev);
343         if (err < 0)
344                 goto failed_free;
345
346         return t;
347
348 failed_free:
349         ip6_dev_free(dev);
350 failed:
351         return NULL;
352 }
353
354 /**
355  * ip6_tnl_locate - find or create tunnel matching given parameters
356  *   @p: tunnel parameters
357  *   @create: != 0 if allowed to create new tunnel if no match found
358  *
359  * Description:
360  *   ip6_tnl_locate() first tries to locate an existing tunnel
361  *   based on @parms. If this is unsuccessful, but @create is set a new
362  *   tunnel device is created and registered for use.
363  *
364  * Return:
365  *   matching tunnel or NULL
366  **/
367
368 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
369                 struct __ip6_tnl_parm *p, int create)
370 {
371         const struct in6_addr *remote = &p->raddr;
372         const struct in6_addr *local = &p->laddr;
373         struct ip6_tnl __rcu **tp;
374         struct ip6_tnl *t;
375         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
376
377         for (tp = ip6_tnl_bucket(ip6n, p);
378              (t = rtnl_dereference(*tp)) != NULL;
379              tp = &t->next) {
380                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
381                     ipv6_addr_equal(remote, &t->parms.raddr)) {
382                         if (create)
383                                 return NULL;
384
385                         return t;
386                 }
387         }
388         if (!create)
389                 return NULL;
390         return ip6_tnl_create(net, p);
391 }
392
393 /**
394  * ip6_tnl_dev_uninit - tunnel device uninitializer
395  *   @dev: the device to be destroyed
396  *
397  * Description:
398  *   ip6_tnl_dev_uninit() removes tunnel from its list
399  **/
400
401 static void
402 ip6_tnl_dev_uninit(struct net_device *dev)
403 {
404         struct ip6_tnl *t = netdev_priv(dev);
405         struct net *net = t->net;
406         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
407
408         if (dev == ip6n->fb_tnl_dev)
409                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
410         else
411                 ip6_tnl_unlink(ip6n, t);
412         ip6_tnl_dst_reset(t);
413         dev_put(dev);
414 }
415
416 /**
417  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
418  *   @skb: received socket buffer
419  *
420  * Return:
421  *   0 if none was found,
422  *   else index to encapsulation limit
423  **/
424
425 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
426 {
427         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
428         __u8 nexthdr = ipv6h->nexthdr;
429         __u16 off = sizeof(*ipv6h);
430
431         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
432                 __u16 optlen = 0;
433                 struct ipv6_opt_hdr *hdr;
434                 if (raw + off + sizeof(*hdr) > skb->data &&
435                     !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
436                         break;
437
438                 hdr = (struct ipv6_opt_hdr *) (raw + off);
439                 if (nexthdr == NEXTHDR_FRAGMENT) {
440                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
441                         if (frag_hdr->frag_off)
442                                 break;
443                         optlen = 8;
444                 } else if (nexthdr == NEXTHDR_AUTH) {
445                         optlen = (hdr->hdrlen + 2) << 2;
446                 } else {
447                         optlen = ipv6_optlen(hdr);
448                 }
449                 if (nexthdr == NEXTHDR_DEST) {
450                         __u16 i = off + 2;
451                         while (1) {
452                                 struct ipv6_tlv_tnl_enc_lim *tel;
453
454                                 /* No more room for encapsulation limit */
455                                 if (i + sizeof (*tel) > off + optlen)
456                                         break;
457
458                                 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
459                                 /* return index of option if found and valid */
460                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
461                                     tel->length == 1)
462                                         return i;
463                                 /* else jump to next option */
464                                 if (tel->type)
465                                         i += tel->length + 2;
466                                 else
467                                         i++;
468                         }
469                 }
470                 nexthdr = hdr->nexthdr;
471                 off += optlen;
472         }
473         return 0;
474 }
475 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
476
477 /**
478  * ip6_tnl_err - tunnel error handler
479  *
480  * Description:
481  *   ip6_tnl_err() should handle errors in the tunnel according
482  *   to the specifications in RFC 2473.
483  **/
484
485 static int
486 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
487             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
488 {
489         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
490         struct ip6_tnl *t;
491         int rel_msg = 0;
492         u8 rel_type = ICMPV6_DEST_UNREACH;
493         u8 rel_code = ICMPV6_ADDR_UNREACH;
494         u8 tproto;
495         __u32 rel_info = 0;
496         __u16 len;
497         int err = -ENOENT;
498
499         /* If the packet doesn't contain the original IPv6 header we are
500            in trouble since we might need the source address for further
501            processing of the error. */
502
503         rcu_read_lock();
504         t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, &ipv6h->saddr);
505         if (t == NULL)
506                 goto out;
507
508         tproto = ACCESS_ONCE(t->parms.proto);
509         if (tproto != ipproto && tproto != 0)
510                 goto out;
511
512         err = 0;
513
514         switch (*type) {
515                 __u32 teli;
516                 struct ipv6_tlv_tnl_enc_lim *tel;
517                 __u32 mtu;
518         case ICMPV6_DEST_UNREACH:
519                 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
520                                      t->parms.name);
521                 rel_msg = 1;
522                 break;
523         case ICMPV6_TIME_EXCEED:
524                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
525                         net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
526                                              t->parms.name);
527                         rel_msg = 1;
528                 }
529                 break;
530         case ICMPV6_PARAMPROB:
531                 teli = 0;
532                 if ((*code) == ICMPV6_HDR_FIELD)
533                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
534
535                 if (teli && teli == *info - 2) {
536                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
537                         if (tel->encap_limit == 0) {
538                                 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
539                                                      t->parms.name);
540                                 rel_msg = 1;
541                         }
542                 } else {
543                         net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
544                                              t->parms.name);
545                 }
546                 break;
547         case ICMPV6_PKT_TOOBIG:
548                 mtu = *info - offset;
549                 if (mtu < IPV6_MIN_MTU)
550                         mtu = IPV6_MIN_MTU;
551                 t->dev->mtu = mtu;
552
553                 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
554                 if (len > mtu) {
555                         rel_type = ICMPV6_PKT_TOOBIG;
556                         rel_code = 0;
557                         rel_info = mtu;
558                         rel_msg = 1;
559                 }
560                 break;
561         }
562
563         *type = rel_type;
564         *code = rel_code;
565         *info = rel_info;
566         *msg = rel_msg;
567
568 out:
569         rcu_read_unlock();
570         return err;
571 }
572
573 static int
574 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
575            u8 type, u8 code, int offset, __be32 info)
576 {
577         int rel_msg = 0;
578         u8 rel_type = type;
579         u8 rel_code = code;
580         __u32 rel_info = ntohl(info);
581         int err;
582         struct sk_buff *skb2;
583         const struct iphdr *eiph;
584         struct rtable *rt;
585         struct flowi4 fl4;
586
587         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
588                           &rel_msg, &rel_info, offset);
589         if (err < 0)
590                 return err;
591
592         if (rel_msg == 0)
593                 return 0;
594
595         switch (rel_type) {
596         case ICMPV6_DEST_UNREACH:
597                 if (rel_code != ICMPV6_ADDR_UNREACH)
598                         return 0;
599                 rel_type = ICMP_DEST_UNREACH;
600                 rel_code = ICMP_HOST_UNREACH;
601                 break;
602         case ICMPV6_PKT_TOOBIG:
603                 if (rel_code != 0)
604                         return 0;
605                 rel_type = ICMP_DEST_UNREACH;
606                 rel_code = ICMP_FRAG_NEEDED;
607                 break;
608         case NDISC_REDIRECT:
609                 rel_type = ICMP_REDIRECT;
610                 rel_code = ICMP_REDIR_HOST;
611         default:
612                 return 0;
613         }
614
615         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
616                 return 0;
617
618         skb2 = skb_clone(skb, GFP_ATOMIC);
619         if (!skb2)
620                 return 0;
621
622         skb_dst_drop(skb2);
623
624         skb_pull(skb2, offset);
625         skb_reset_network_header(skb2);
626         eiph = ip_hdr(skb2);
627
628         /* Try to guess incoming interface */
629         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
630                                    eiph->saddr, 0,
631                                    0, 0,
632                                    IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
633         if (IS_ERR(rt))
634                 goto out;
635
636         skb2->dev = rt->dst.dev;
637
638         /* route "incoming" packet */
639         if (rt->rt_flags & RTCF_LOCAL) {
640                 ip_rt_put(rt);
641                 rt = NULL;
642                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
643                                            eiph->daddr, eiph->saddr,
644                                            0, 0,
645                                            IPPROTO_IPIP,
646                                            RT_TOS(eiph->tos), 0);
647                 if (IS_ERR(rt) ||
648                     rt->dst.dev->type != ARPHRD_TUNNEL) {
649                         if (!IS_ERR(rt))
650                                 ip_rt_put(rt);
651                         goto out;
652                 }
653                 skb_dst_set(skb2, &rt->dst);
654         } else {
655                 ip_rt_put(rt);
656                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
657                                    skb2->dev) ||
658                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
659                         goto out;
660         }
661
662         /* change mtu on this route */
663         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
664                 if (rel_info > dst_mtu(skb_dst(skb2)))
665                         goto out;
666
667                 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info);
668         }
669         if (rel_type == ICMP_REDIRECT)
670                 skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2);
671
672         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
673
674 out:
675         kfree_skb(skb2);
676         return 0;
677 }
678
679 static int
680 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
681            u8 type, u8 code, int offset, __be32 info)
682 {
683         int rel_msg = 0;
684         u8 rel_type = type;
685         u8 rel_code = code;
686         __u32 rel_info = ntohl(info);
687         int err;
688
689         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
690                           &rel_msg, &rel_info, offset);
691         if (err < 0)
692                 return err;
693
694         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
695                 struct rt6_info *rt;
696                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
697
698                 if (!skb2)
699                         return 0;
700
701                 skb_dst_drop(skb2);
702                 skb_pull(skb2, offset);
703                 skb_reset_network_header(skb2);
704
705                 /* Try to guess incoming interface */
706                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
707                                 NULL, 0, 0);
708
709                 if (rt && rt->dst.dev)
710                         skb2->dev = rt->dst.dev;
711
712                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
713
714                 ip6_rt_put(rt);
715
716                 kfree_skb(skb2);
717         }
718
719         return 0;
720 }
721
722 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
723                                        const struct ipv6hdr *ipv6h,
724                                        struct sk_buff *skb)
725 {
726         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
727
728         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
729                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
730
731         return IP6_ECN_decapsulate(ipv6h, skb);
732 }
733
734 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
735                                        const struct ipv6hdr *ipv6h,
736                                        struct sk_buff *skb)
737 {
738         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
739                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
740
741         return IP6_ECN_decapsulate(ipv6h, skb);
742 }
743
744 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
745                              const struct in6_addr *laddr,
746                              const struct in6_addr *raddr)
747 {
748         struct __ip6_tnl_parm *p = &t->parms;
749         int ltype = ipv6_addr_type(laddr);
750         int rtype = ipv6_addr_type(raddr);
751         __u32 flags = 0;
752
753         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
754                 flags = IP6_TNL_F_CAP_PER_PACKET;
755         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
756                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
757                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
758                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
759                 if (ltype&IPV6_ADDR_UNICAST)
760                         flags |= IP6_TNL_F_CAP_XMIT;
761                 if (rtype&IPV6_ADDR_UNICAST)
762                         flags |= IP6_TNL_F_CAP_RCV;
763         }
764         return flags;
765 }
766 EXPORT_SYMBOL(ip6_tnl_get_cap);
767
768 /* called with rcu_read_lock() */
769 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
770                                   const struct in6_addr *laddr,
771                                   const struct in6_addr *raddr)
772 {
773         struct __ip6_tnl_parm *p = &t->parms;
774         int ret = 0;
775         struct net *net = t->net;
776
777         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
778             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
779              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
780                 struct net_device *ldev = NULL;
781
782                 if (p->link)
783                         ldev = dev_get_by_index_rcu(net, p->link);
784
785                 if ((ipv6_addr_is_multicast(laddr) ||
786                      likely(ipv6_chk_addr(net, laddr, ldev, 0))) &&
787                     likely(!ipv6_chk_addr(net, raddr, NULL, 0)))
788                         ret = 1;
789         }
790         return ret;
791 }
792 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
793
794 /**
795  * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
796  *   @skb: received socket buffer
797  *   @protocol: ethernet protocol ID
798  *   @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN
799  *
800  * Return: 0
801  **/
802
803 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
804                        __u8 ipproto,
805                        int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
806                                                    const struct ipv6hdr *ipv6h,
807                                                    struct sk_buff *skb))
808 {
809         struct ip6_tnl *t;
810         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
811         u8 tproto;
812         int err;
813
814         rcu_read_lock();
815         t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
816         if (t != NULL) {
817                 struct pcpu_sw_netstats *tstats;
818
819                 tproto = ACCESS_ONCE(t->parms.proto);
820                 if (tproto != ipproto && tproto != 0) {
821                         rcu_read_unlock();
822                         goto discard;
823                 }
824
825                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
826                         rcu_read_unlock();
827                         goto discard;
828                 }
829
830                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
831                         t->dev->stats.rx_dropped++;
832                         rcu_read_unlock();
833                         goto discard;
834                 }
835                 skb->mac_header = skb->network_header;
836                 skb_reset_network_header(skb);
837                 skb->protocol = htons(protocol);
838                 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
839
840                 __skb_tunnel_rx(skb, t->dev, t->net);
841
842                 err = dscp_ecn_decapsulate(t, ipv6h, skb);
843                 if (unlikely(err)) {
844                         if (log_ecn_error)
845                                 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n",
846                                                      &ipv6h->saddr,
847                                                      ipv6_get_dsfield(ipv6h));
848                         if (err > 1) {
849                                 ++t->dev->stats.rx_frame_errors;
850                                 ++t->dev->stats.rx_errors;
851                                 rcu_read_unlock();
852                                 goto discard;
853                         }
854                 }
855
856                 tstats = this_cpu_ptr(t->dev->tstats);
857                 u64_stats_update_begin(&tstats->syncp);
858                 tstats->rx_packets++;
859                 tstats->rx_bytes += skb->len;
860                 u64_stats_update_end(&tstats->syncp);
861
862                 netif_rx(skb);
863
864                 rcu_read_unlock();
865                 return 0;
866         }
867         rcu_read_unlock();
868         return 1;
869
870 discard:
871         kfree_skb(skb);
872         return 0;
873 }
874
875 static int ip4ip6_rcv(struct sk_buff *skb)
876 {
877         return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
878                            ip4ip6_dscp_ecn_decapsulate);
879 }
880
881 static int ip6ip6_rcv(struct sk_buff *skb)
882 {
883         return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
884                            ip6ip6_dscp_ecn_decapsulate);
885 }
886
887 struct ipv6_tel_txoption {
888         struct ipv6_txoptions ops;
889         __u8 dst_opt[8];
890 };
891
892 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
893 {
894         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
895
896         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
897         opt->dst_opt[3] = 1;
898         opt->dst_opt[4] = encap_limit;
899         opt->dst_opt[5] = IPV6_TLV_PADN;
900         opt->dst_opt[6] = 1;
901
902         opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
903         opt->ops.opt_nflen = 8;
904 }
905
906 /**
907  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
908  *   @t: the outgoing tunnel device
909  *   @hdr: IPv6 header from the incoming packet
910  *
911  * Description:
912  *   Avoid trivial tunneling loop by checking that tunnel exit-point
913  *   doesn't match source of incoming packet.
914  *
915  * Return:
916  *   1 if conflict,
917  *   0 else
918  **/
919
920 static inline bool
921 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
922 {
923         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
924 }
925
926 int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
927                      const struct in6_addr *laddr,
928                      const struct in6_addr *raddr)
929 {
930         struct __ip6_tnl_parm *p = &t->parms;
931         int ret = 0;
932         struct net *net = t->net;
933
934         if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
935             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
936              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
937                 struct net_device *ldev = NULL;
938
939                 rcu_read_lock();
940                 if (p->link)
941                         ldev = dev_get_by_index_rcu(net, p->link);
942
943                 if (unlikely(!ipv6_chk_addr(net, laddr, ldev, 0)))
944                         pr_warn("%s xmit: Local address not yet configured!\n",
945                                 p->name);
946                 else if (!ipv6_addr_is_multicast(raddr) &&
947                          unlikely(ipv6_chk_addr(net, raddr, NULL, 0)))
948                         pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
949                                 p->name);
950                 else
951                         ret = 1;
952                 rcu_read_unlock();
953         }
954         return ret;
955 }
956 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
957
958 /**
959  * ip6_tnl_xmit2 - encapsulate packet and send
960  *   @skb: the outgoing socket buffer
961  *   @dev: the outgoing tunnel device
962  *   @dsfield: dscp code for outer header
963  *   @fl: flow of tunneled packet
964  *   @encap_limit: encapsulation limit
965  *   @pmtu: Path MTU is stored if packet is too big
966  *
967  * Description:
968  *   Build new header and do some sanity checks on the packet before sending
969  *   it.
970  *
971  * Return:
972  *   0 on success
973  *   -1 fail
974  *   %-EMSGSIZE message too big. return mtu in this case.
975  **/
976
977 static int ip6_tnl_xmit2(struct sk_buff *skb,
978                          struct net_device *dev,
979                          __u8 dsfield,
980                          struct flowi6 *fl6,
981                          int encap_limit,
982                          __u32 *pmtu)
983 {
984         struct ip6_tnl *t = netdev_priv(dev);
985         struct net *net = t->net;
986         struct net_device_stats *stats = &t->dev->stats;
987         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
988         struct ipv6_tel_txoption opt;
989         struct dst_entry *dst = NULL, *ndst = NULL;
990         struct net_device *tdev;
991         int mtu;
992         unsigned int max_headroom = sizeof(struct ipv6hdr);
993         u8 proto;
994         int err = -1;
995
996         /* NBMA tunnel */
997         if (ipv6_addr_any(&t->parms.raddr)) {
998                 struct in6_addr *addr6;
999                 struct neighbour *neigh;
1000                 int addr_type;
1001
1002                 if (!skb_dst(skb))
1003                         goto tx_err_link_failure;
1004
1005                 neigh = dst_neigh_lookup(skb_dst(skb),
1006                                          &ipv6_hdr(skb)->daddr);
1007                 if (!neigh)
1008                         goto tx_err_link_failure;
1009
1010                 addr6 = (struct in6_addr *)&neigh->primary_key;
1011                 addr_type = ipv6_addr_type(addr6);
1012
1013                 if (addr_type == IPV6_ADDR_ANY)
1014                         addr6 = &ipv6_hdr(skb)->daddr;
1015
1016                 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1017                 neigh_release(neigh);
1018         } else if (!fl6->flowi6_mark)
1019                 dst = ip6_tnl_dst_check(t);
1020
1021         if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1022                 goto tx_err_link_failure;
1023
1024         if (!dst) {
1025                 ndst = ip6_route_output(net, NULL, fl6);
1026
1027                 if (ndst->error)
1028                         goto tx_err_link_failure;
1029                 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
1030                 if (IS_ERR(ndst)) {
1031                         err = PTR_ERR(ndst);
1032                         ndst = NULL;
1033                         goto tx_err_link_failure;
1034                 }
1035                 dst = ndst;
1036         }
1037
1038         tdev = dst->dev;
1039
1040         if (tdev == dev) {
1041                 stats->collisions++;
1042                 net_warn_ratelimited("%s: Local routing loop detected!\n",
1043                                      t->parms.name);
1044                 goto tx_err_dst_release;
1045         }
1046         mtu = dst_mtu(dst) - sizeof(*ipv6h);
1047         if (encap_limit >= 0) {
1048                 max_headroom += 8;
1049                 mtu -= 8;
1050         }
1051         if (mtu < IPV6_MIN_MTU)
1052                 mtu = IPV6_MIN_MTU;
1053         if (skb_dst(skb))
1054                 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
1055         if (skb->len > mtu) {
1056                 *pmtu = mtu;
1057                 err = -EMSGSIZE;
1058                 goto tx_err_dst_release;
1059         }
1060
1061         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1062
1063         /*
1064          * Okay, now see if we can stuff it in the buffer as-is.
1065          */
1066         max_headroom += LL_RESERVED_SPACE(tdev);
1067
1068         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1069             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1070                 struct sk_buff *new_skb;
1071
1072                 new_skb = skb_realloc_headroom(skb, max_headroom);
1073                 if (!new_skb)
1074                         goto tx_err_dst_release;
1075
1076                 if (skb->sk)
1077                         skb_set_owner_w(new_skb, skb->sk);
1078                 consume_skb(skb);
1079                 skb = new_skb;
1080         }
1081         if (fl6->flowi6_mark) {
1082                 skb_dst_set(skb, dst);
1083                 ndst = NULL;
1084         } else {
1085                 skb_dst_set_noref(skb, dst);
1086         }
1087         skb->transport_header = skb->network_header;
1088
1089         proto = fl6->flowi6_proto;
1090         if (encap_limit >= 0) {
1091                 init_tel_txopt(&opt, encap_limit);
1092                 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
1093         }
1094
1095         if (likely(!skb->encapsulation)) {
1096                 skb_reset_inner_headers(skb);
1097                 skb->encapsulation = 1;
1098         }
1099
1100         skb_push(skb, sizeof(struct ipv6hdr));
1101         skb_reset_network_header(skb);
1102         ipv6h = ipv6_hdr(skb);
1103         ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield),
1104                      ip6_make_flowlabel(net, skb, fl6->flowlabel, false));
1105         ipv6h->hop_limit = t->parms.hop_limit;
1106         ipv6h->nexthdr = proto;
1107         ipv6h->saddr = fl6->saddr;
1108         ipv6h->daddr = fl6->daddr;
1109         ip6tunnel_xmit(skb, dev);
1110         if (ndst)
1111                 ip6_tnl_dst_store(t, ndst);
1112         return 0;
1113 tx_err_link_failure:
1114         stats->tx_carrier_errors++;
1115         dst_link_failure(skb);
1116 tx_err_dst_release:
1117         dst_release(ndst);
1118         return err;
1119 }
1120
1121 static inline int
1122 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1123 {
1124         struct ip6_tnl *t = netdev_priv(dev);
1125         const struct iphdr  *iph = ip_hdr(skb);
1126         int encap_limit = -1;
1127         struct flowi6 fl6;
1128         __u8 dsfield;
1129         __u32 mtu;
1130         u8 tproto;
1131         int err;
1132
1133         tproto = ACCESS_ONCE(t->parms.proto);
1134         if (tproto != IPPROTO_IPIP && tproto != 0)
1135                 return -1;
1136
1137         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1138                 encap_limit = t->parms.encap_limit;
1139
1140         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1141         fl6.flowi6_proto = IPPROTO_IPIP;
1142
1143         dsfield = ipv4_get_dsfield(iph);
1144
1145         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1146                 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1147                                           & IPV6_TCLASS_MASK;
1148         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1149                 fl6.flowi6_mark = skb->mark;
1150
1151         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1152         if (err != 0) {
1153                 /* XXX: send ICMP error even if DF is not set. */
1154                 if (err == -EMSGSIZE)
1155                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1156                                   htonl(mtu));
1157                 return -1;
1158         }
1159
1160         return 0;
1161 }
1162
1163 static inline int
1164 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1165 {
1166         struct ip6_tnl *t = netdev_priv(dev);
1167         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1168         int encap_limit = -1;
1169         __u16 offset;
1170         struct flowi6 fl6;
1171         __u8 dsfield;
1172         __u32 mtu;
1173         u8 tproto;
1174         int err;
1175
1176         tproto = ACCESS_ONCE(t->parms.proto);
1177         if ((tproto != IPPROTO_IPV6 && tproto != 0) ||
1178             ip6_tnl_addr_conflict(t, ipv6h))
1179                 return -1;
1180
1181         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
1182         if (offset > 0) {
1183                 struct ipv6_tlv_tnl_enc_lim *tel;
1184                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
1185                 if (tel->encap_limit == 0) {
1186                         icmpv6_send(skb, ICMPV6_PARAMPROB,
1187                                     ICMPV6_HDR_FIELD, offset + 2);
1188                         return -1;
1189                 }
1190                 encap_limit = tel->encap_limit - 1;
1191         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1192                 encap_limit = t->parms.encap_limit;
1193
1194         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1195         fl6.flowi6_proto = IPPROTO_IPV6;
1196
1197         dsfield = ipv6_get_dsfield(ipv6h);
1198         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1199                 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1200         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1201                 fl6.flowlabel |= ip6_flowlabel(ipv6h);
1202         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1203                 fl6.flowi6_mark = skb->mark;
1204
1205         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1206         if (err != 0) {
1207                 if (err == -EMSGSIZE)
1208                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1209                 return -1;
1210         }
1211
1212         return 0;
1213 }
1214
1215 static netdev_tx_t
1216 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1217 {
1218         struct ip6_tnl *t = netdev_priv(dev);
1219         struct net_device_stats *stats = &t->dev->stats;
1220         int ret;
1221
1222         switch (skb->protocol) {
1223         case htons(ETH_P_IP):
1224                 ret = ip4ip6_tnl_xmit(skb, dev);
1225                 break;
1226         case htons(ETH_P_IPV6):
1227                 ret = ip6ip6_tnl_xmit(skb, dev);
1228                 break;
1229         default:
1230                 goto tx_err;
1231         }
1232
1233         if (ret < 0)
1234                 goto tx_err;
1235
1236         return NETDEV_TX_OK;
1237
1238 tx_err:
1239         stats->tx_errors++;
1240         stats->tx_dropped++;
1241         kfree_skb(skb);
1242         return NETDEV_TX_OK;
1243 }
1244
1245 static void ip6_tnl_link_config(struct ip6_tnl *t)
1246 {
1247         struct net_device *dev = t->dev;
1248         struct __ip6_tnl_parm *p = &t->parms;
1249         struct flowi6 *fl6 = &t->fl.u.ip6;
1250
1251         memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1252         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1253
1254         /* Set up flowi template */
1255         fl6->saddr = p->laddr;
1256         fl6->daddr = p->raddr;
1257         fl6->flowi6_oif = p->link;
1258         fl6->flowlabel = 0;
1259
1260         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1261                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1262         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1263                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1264
1265         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1266         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1267
1268         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1269                 dev->flags |= IFF_POINTOPOINT;
1270         else
1271                 dev->flags &= ~IFF_POINTOPOINT;
1272
1273         dev->iflink = p->link;
1274
1275         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1276                 int strict = (ipv6_addr_type(&p->raddr) &
1277                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1278
1279                 struct rt6_info *rt = rt6_lookup(t->net,
1280                                                  &p->raddr, &p->laddr,
1281                                                  p->link, strict);
1282
1283                 if (rt == NULL)
1284                         return;
1285
1286                 if (rt->dst.dev) {
1287                         dev->hard_header_len = rt->dst.dev->hard_header_len +
1288                                 sizeof(struct ipv6hdr);
1289
1290                         dev->mtu = rt->dst.dev->mtu - sizeof(struct ipv6hdr);
1291                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1292                                 dev->mtu -= 8;
1293
1294                         if (dev->mtu < IPV6_MIN_MTU)
1295                                 dev->mtu = IPV6_MIN_MTU;
1296                 }
1297                 ip6_rt_put(rt);
1298         }
1299 }
1300
1301 /**
1302  * ip6_tnl_change - update the tunnel parameters
1303  *   @t: tunnel to be changed
1304  *   @p: tunnel configuration parameters
1305  *
1306  * Description:
1307  *   ip6_tnl_change() updates the tunnel parameters
1308  **/
1309
1310 static int
1311 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1312 {
1313         t->parms.laddr = p->laddr;
1314         t->parms.raddr = p->raddr;
1315         t->parms.flags = p->flags;
1316         t->parms.hop_limit = p->hop_limit;
1317         t->parms.encap_limit = p->encap_limit;
1318         t->parms.flowinfo = p->flowinfo;
1319         t->parms.link = p->link;
1320         t->parms.proto = p->proto;
1321         ip6_tnl_dst_reset(t);
1322         ip6_tnl_link_config(t);
1323         return 0;
1324 }
1325
1326 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1327 {
1328         struct net *net = t->net;
1329         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1330         int err;
1331
1332         ip6_tnl_unlink(ip6n, t);
1333         synchronize_net();
1334         err = ip6_tnl_change(t, p);
1335         ip6_tnl_link(ip6n, t);
1336         netdev_state_change(t->dev);
1337         return err;
1338 }
1339
1340 static int ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1341 {
1342         /* for default tnl0 device allow to change only the proto */
1343         t->parms.proto = p->proto;
1344         netdev_state_change(t->dev);
1345         return 0;
1346 }
1347
1348 static void
1349 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1350 {
1351         p->laddr = u->laddr;
1352         p->raddr = u->raddr;
1353         p->flags = u->flags;
1354         p->hop_limit = u->hop_limit;
1355         p->encap_limit = u->encap_limit;
1356         p->flowinfo = u->flowinfo;
1357         p->link = u->link;
1358         p->proto = u->proto;
1359         memcpy(p->name, u->name, sizeof(u->name));
1360 }
1361
1362 static void
1363 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1364 {
1365         u->laddr = p->laddr;
1366         u->raddr = p->raddr;
1367         u->flags = p->flags;
1368         u->hop_limit = p->hop_limit;
1369         u->encap_limit = p->encap_limit;
1370         u->flowinfo = p->flowinfo;
1371         u->link = p->link;
1372         u->proto = p->proto;
1373         memcpy(u->name, p->name, sizeof(u->name));
1374 }
1375
1376 /**
1377  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1378  *   @dev: virtual device associated with tunnel
1379  *   @ifr: parameters passed from userspace
1380  *   @cmd: command to be performed
1381  *
1382  * Description:
1383  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1384  *   from userspace.
1385  *
1386  *   The possible commands are the following:
1387  *     %SIOCGETTUNNEL: get tunnel parameters for device
1388  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1389  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1390  *     %SIOCDELTUNNEL: delete tunnel
1391  *
1392  *   The fallback device "ip6tnl0", created during module
1393  *   initialization, can be used for creating other tunnel devices.
1394  *
1395  * Return:
1396  *   0 on success,
1397  *   %-EFAULT if unable to copy data to or from userspace,
1398  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1399  *   %-EINVAL if passed tunnel parameters are invalid,
1400  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1401  *   %-ENODEV if attempting to change or delete a nonexisting device
1402  **/
1403
1404 static int
1405 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1406 {
1407         int err = 0;
1408         struct ip6_tnl_parm p;
1409         struct __ip6_tnl_parm p1;
1410         struct ip6_tnl *t = netdev_priv(dev);
1411         struct net *net = t->net;
1412         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1413
1414         switch (cmd) {
1415         case SIOCGETTUNNEL:
1416                 if (dev == ip6n->fb_tnl_dev) {
1417                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1418                                 err = -EFAULT;
1419                                 break;
1420                         }
1421                         ip6_tnl_parm_from_user(&p1, &p);
1422                         t = ip6_tnl_locate(net, &p1, 0);
1423                         if (t == NULL)
1424                                 t = netdev_priv(dev);
1425                 } else {
1426                         memset(&p, 0, sizeof(p));
1427                 }
1428                 ip6_tnl_parm_to_user(&p, &t->parms);
1429                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) {
1430                         err = -EFAULT;
1431                 }
1432                 break;
1433         case SIOCADDTUNNEL:
1434         case SIOCCHGTUNNEL:
1435                 err = -EPERM;
1436                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1437                         break;
1438                 err = -EFAULT;
1439                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1440                         break;
1441                 err = -EINVAL;
1442                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1443                     p.proto != 0)
1444                         break;
1445                 ip6_tnl_parm_from_user(&p1, &p);
1446                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1447                 if (cmd == SIOCCHGTUNNEL) {
1448                         if (t != NULL) {
1449                                 if (t->dev != dev) {
1450                                         err = -EEXIST;
1451                                         break;
1452                                 }
1453                         } else
1454                                 t = netdev_priv(dev);
1455                         if (dev == ip6n->fb_tnl_dev)
1456                                 err = ip6_tnl0_update(t, &p1);
1457                         else
1458                                 err = ip6_tnl_update(t, &p1);
1459                 }
1460                 if (t) {
1461                         err = 0;
1462                         ip6_tnl_parm_to_user(&p, &t->parms);
1463                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1464                                 err = -EFAULT;
1465
1466                 } else
1467                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1468                 break;
1469         case SIOCDELTUNNEL:
1470                 err = -EPERM;
1471                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1472                         break;
1473
1474                 if (dev == ip6n->fb_tnl_dev) {
1475                         err = -EFAULT;
1476                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1477                                 break;
1478                         err = -ENOENT;
1479                         ip6_tnl_parm_from_user(&p1, &p);
1480                         t = ip6_tnl_locate(net, &p1, 0);
1481                         if (t == NULL)
1482                                 break;
1483                         err = -EPERM;
1484                         if (t->dev == ip6n->fb_tnl_dev)
1485                                 break;
1486                         dev = t->dev;
1487                 }
1488                 err = 0;
1489                 unregister_netdevice(dev);
1490                 break;
1491         default:
1492                 err = -EINVAL;
1493         }
1494         return err;
1495 }
1496
1497 /**
1498  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1499  *   @dev: virtual device associated with tunnel
1500  *   @new_mtu: the new mtu
1501  *
1502  * Return:
1503  *   0 on success,
1504  *   %-EINVAL if mtu too small
1505  **/
1506
1507 static int
1508 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1509 {
1510         struct ip6_tnl *tnl = netdev_priv(dev);
1511
1512         if (tnl->parms.proto == IPPROTO_IPIP) {
1513                 if (new_mtu < 68)
1514                         return -EINVAL;
1515         } else {
1516                 if (new_mtu < IPV6_MIN_MTU)
1517                         return -EINVAL;
1518         }
1519         if (new_mtu > 0xFFF8 - dev->hard_header_len)
1520                 return -EINVAL;
1521         dev->mtu = new_mtu;
1522         return 0;
1523 }
1524
1525
1526 static const struct net_device_ops ip6_tnl_netdev_ops = {
1527         .ndo_init       = ip6_tnl_dev_init,
1528         .ndo_uninit     = ip6_tnl_dev_uninit,
1529         .ndo_start_xmit = ip6_tnl_xmit,
1530         .ndo_do_ioctl   = ip6_tnl_ioctl,
1531         .ndo_change_mtu = ip6_tnl_change_mtu,
1532         .ndo_get_stats  = ip6_get_stats,
1533 };
1534
1535
1536 /**
1537  * ip6_tnl_dev_setup - setup virtual tunnel device
1538  *   @dev: virtual device associated with tunnel
1539  *
1540  * Description:
1541  *   Initialize function pointers and device parameters
1542  **/
1543
1544 static void ip6_tnl_dev_setup(struct net_device *dev)
1545 {
1546         struct ip6_tnl *t;
1547
1548         dev->netdev_ops = &ip6_tnl_netdev_ops;
1549         dev->destructor = ip6_dev_free;
1550
1551         dev->type = ARPHRD_TUNNEL6;
1552         dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
1553         dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr);
1554         t = netdev_priv(dev);
1555         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1556                 dev->mtu -= 8;
1557         dev->flags |= IFF_NOARP;
1558         dev->addr_len = sizeof(struct in6_addr);
1559         netif_keep_dst(dev);
1560         /* This perm addr will be used as interface identifier by IPv6 */
1561         dev->addr_assign_type = NET_ADDR_RANDOM;
1562         eth_random_addr(dev->perm_addr);
1563 }
1564
1565
1566 /**
1567  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1568  *   @dev: virtual device associated with tunnel
1569  **/
1570
1571 static inline int
1572 ip6_tnl_dev_init_gen(struct net_device *dev)
1573 {
1574         struct ip6_tnl *t = netdev_priv(dev);
1575
1576         t->dev = dev;
1577         t->net = dev_net(dev);
1578         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1579         if (!dev->tstats)
1580                 return -ENOMEM;
1581         return 0;
1582 }
1583
1584 /**
1585  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1586  *   @dev: virtual device associated with tunnel
1587  **/
1588
1589 static int ip6_tnl_dev_init(struct net_device *dev)
1590 {
1591         struct ip6_tnl *t = netdev_priv(dev);
1592         int err = ip6_tnl_dev_init_gen(dev);
1593
1594         if (err)
1595                 return err;
1596         ip6_tnl_link_config(t);
1597         return 0;
1598 }
1599
1600 /**
1601  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1602  *   @dev: fallback device
1603  *
1604  * Return: 0
1605  **/
1606
1607 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1608 {
1609         struct ip6_tnl *t = netdev_priv(dev);
1610         struct net *net = dev_net(dev);
1611         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1612
1613         t->parms.proto = IPPROTO_IPV6;
1614         dev_hold(dev);
1615
1616         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1617         return 0;
1618 }
1619
1620 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[])
1621 {
1622         u8 proto;
1623
1624         if (!data || !data[IFLA_IPTUN_PROTO])
1625                 return 0;
1626
1627         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1628         if (proto != IPPROTO_IPV6 &&
1629             proto != IPPROTO_IPIP &&
1630             proto != 0)
1631                 return -EINVAL;
1632
1633         return 0;
1634 }
1635
1636 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1637                                   struct __ip6_tnl_parm *parms)
1638 {
1639         memset(parms, 0, sizeof(*parms));
1640
1641         if (!data)
1642                 return;
1643
1644         if (data[IFLA_IPTUN_LINK])
1645                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1646
1647         if (data[IFLA_IPTUN_LOCAL])
1648                 nla_memcpy(&parms->laddr, data[IFLA_IPTUN_LOCAL],
1649                            sizeof(struct in6_addr));
1650
1651         if (data[IFLA_IPTUN_REMOTE])
1652                 nla_memcpy(&parms->raddr, data[IFLA_IPTUN_REMOTE],
1653                            sizeof(struct in6_addr));
1654
1655         if (data[IFLA_IPTUN_TTL])
1656                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1657
1658         if (data[IFLA_IPTUN_ENCAP_LIMIT])
1659                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1660
1661         if (data[IFLA_IPTUN_FLOWINFO])
1662                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1663
1664         if (data[IFLA_IPTUN_FLAGS])
1665                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1666
1667         if (data[IFLA_IPTUN_PROTO])
1668                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1669 }
1670
1671 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
1672                            struct nlattr *tb[], struct nlattr *data[])
1673 {
1674         struct net *net = dev_net(dev);
1675         struct ip6_tnl *nt;
1676
1677         nt = netdev_priv(dev);
1678         ip6_tnl_netlink_parms(data, &nt->parms);
1679
1680         if (ip6_tnl_locate(net, &nt->parms, 0))
1681                 return -EEXIST;
1682
1683         return ip6_tnl_create2(dev);
1684 }
1685
1686 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
1687                               struct nlattr *data[])
1688 {
1689         struct ip6_tnl *t = netdev_priv(dev);
1690         struct __ip6_tnl_parm p;
1691         struct net *net = t->net;
1692         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1693
1694         if (dev == ip6n->fb_tnl_dev)
1695                 return -EINVAL;
1696
1697         ip6_tnl_netlink_parms(data, &p);
1698
1699         t = ip6_tnl_locate(net, &p, 0);
1700
1701         if (t) {
1702                 if (t->dev != dev)
1703                         return -EEXIST;
1704         } else
1705                 t = netdev_priv(dev);
1706
1707         return ip6_tnl_update(t, &p);
1708 }
1709
1710 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
1711 {
1712         struct net *net = dev_net(dev);
1713         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1714
1715         if (dev != ip6n->fb_tnl_dev)
1716                 unregister_netdevice_queue(dev, head);
1717 }
1718
1719 static size_t ip6_tnl_get_size(const struct net_device *dev)
1720 {
1721         return
1722                 /* IFLA_IPTUN_LINK */
1723                 nla_total_size(4) +
1724                 /* IFLA_IPTUN_LOCAL */
1725                 nla_total_size(sizeof(struct in6_addr)) +
1726                 /* IFLA_IPTUN_REMOTE */
1727                 nla_total_size(sizeof(struct in6_addr)) +
1728                 /* IFLA_IPTUN_TTL */
1729                 nla_total_size(1) +
1730                 /* IFLA_IPTUN_ENCAP_LIMIT */
1731                 nla_total_size(1) +
1732                 /* IFLA_IPTUN_FLOWINFO */
1733                 nla_total_size(4) +
1734                 /* IFLA_IPTUN_FLAGS */
1735                 nla_total_size(4) +
1736                 /* IFLA_IPTUN_PROTO */
1737                 nla_total_size(1) +
1738                 0;
1739 }
1740
1741 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
1742 {
1743         struct ip6_tnl *tunnel = netdev_priv(dev);
1744         struct __ip6_tnl_parm *parm = &tunnel->parms;
1745
1746         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1747             nla_put(skb, IFLA_IPTUN_LOCAL, sizeof(struct in6_addr),
1748                     &parm->laddr) ||
1749             nla_put(skb, IFLA_IPTUN_REMOTE, sizeof(struct in6_addr),
1750                     &parm->raddr) ||
1751             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
1752             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
1753             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
1754             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
1755             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
1756                 goto nla_put_failure;
1757         return 0;
1758
1759 nla_put_failure:
1760         return -EMSGSIZE;
1761 }
1762
1763 struct net *ip6_tnl_get_link_net(const struct net_device *dev)
1764 {
1765         struct ip6_tnl *tunnel = netdev_priv(dev);
1766
1767         return tunnel->net;
1768 }
1769 EXPORT_SYMBOL(ip6_tnl_get_link_net);
1770
1771 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
1772         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
1773         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
1774         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
1775         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
1776         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
1777         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
1778         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
1779         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
1780 };
1781
1782 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
1783         .kind           = "ip6tnl",
1784         .maxtype        = IFLA_IPTUN_MAX,
1785         .policy         = ip6_tnl_policy,
1786         .priv_size      = sizeof(struct ip6_tnl),
1787         .setup          = ip6_tnl_dev_setup,
1788         .validate       = ip6_tnl_validate,
1789         .newlink        = ip6_tnl_newlink,
1790         .changelink     = ip6_tnl_changelink,
1791         .dellink        = ip6_tnl_dellink,
1792         .get_size       = ip6_tnl_get_size,
1793         .fill_info      = ip6_tnl_fill_info,
1794         .get_link_net   = ip6_tnl_get_link_net,
1795 };
1796
1797 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
1798         .handler        = ip4ip6_rcv,
1799         .err_handler    = ip4ip6_err,
1800         .priority       =       1,
1801 };
1802
1803 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
1804         .handler        = ip6ip6_rcv,
1805         .err_handler    = ip6ip6_err,
1806         .priority       =       1,
1807 };
1808
1809 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net)
1810 {
1811         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1812         struct net_device *dev, *aux;
1813         int h;
1814         struct ip6_tnl *t;
1815         LIST_HEAD(list);
1816
1817         for_each_netdev_safe(net, dev, aux)
1818                 if (dev->rtnl_link_ops == &ip6_link_ops)
1819                         unregister_netdevice_queue(dev, &list);
1820
1821         for (h = 0; h < HASH_SIZE; h++) {
1822                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1823                 while (t != NULL) {
1824                         /* If dev is in the same netns, it has already
1825                          * been added to the list by the previous loop.
1826                          */
1827                         if (!net_eq(dev_net(t->dev), net))
1828                                 unregister_netdevice_queue(t->dev, &list);
1829                         t = rtnl_dereference(t->next);
1830                 }
1831         }
1832
1833         unregister_netdevice_many(&list);
1834 }
1835
1836 static int __net_init ip6_tnl_init_net(struct net *net)
1837 {
1838         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1839         struct ip6_tnl *t = NULL;
1840         int err;
1841
1842         ip6n->tnls[0] = ip6n->tnls_wc;
1843         ip6n->tnls[1] = ip6n->tnls_r_l;
1844
1845         err = -ENOMEM;
1846         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1847                                         NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
1848
1849         if (!ip6n->fb_tnl_dev)
1850                 goto err_alloc_dev;
1851         dev_net_set(ip6n->fb_tnl_dev, net);
1852         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
1853         /* FB netdevice is special: we have one, and only one per netns.
1854          * Allowing to move it to another netns is clearly unsafe.
1855          */
1856         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
1857
1858         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1859         if (err < 0)
1860                 goto err_register;
1861
1862         err = register_netdev(ip6n->fb_tnl_dev);
1863         if (err < 0)
1864                 goto err_register;
1865
1866         t = netdev_priv(ip6n->fb_tnl_dev);
1867
1868         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1869         return 0;
1870
1871 err_register:
1872         ip6_dev_free(ip6n->fb_tnl_dev);
1873 err_alloc_dev:
1874         return err;
1875 }
1876
1877 static void __net_exit ip6_tnl_exit_net(struct net *net)
1878 {
1879         rtnl_lock();
1880         ip6_tnl_destroy_tunnels(net);
1881         rtnl_unlock();
1882 }
1883
1884 static struct pernet_operations ip6_tnl_net_ops = {
1885         .init = ip6_tnl_init_net,
1886         .exit = ip6_tnl_exit_net,
1887         .id   = &ip6_tnl_net_id,
1888         .size = sizeof(struct ip6_tnl_net),
1889 };
1890
1891 /**
1892  * ip6_tunnel_init - register protocol and reserve needed resources
1893  *
1894  * Return: 0 on success
1895  **/
1896
1897 static int __init ip6_tunnel_init(void)
1898 {
1899         int  err;
1900
1901         err = register_pernet_device(&ip6_tnl_net_ops);
1902         if (err < 0)
1903                 goto out_pernet;
1904
1905         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
1906         if (err < 0) {
1907                 pr_err("%s: can't register ip4ip6\n", __func__);
1908                 goto out_ip4ip6;
1909         }
1910
1911         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
1912         if (err < 0) {
1913                 pr_err("%s: can't register ip6ip6\n", __func__);
1914                 goto out_ip6ip6;
1915         }
1916         err = rtnl_link_register(&ip6_link_ops);
1917         if (err < 0)
1918                 goto rtnl_link_failed;
1919
1920         return 0;
1921
1922 rtnl_link_failed:
1923         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
1924 out_ip6ip6:
1925         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1926 out_ip4ip6:
1927         unregister_pernet_device(&ip6_tnl_net_ops);
1928 out_pernet:
1929         return err;
1930 }
1931
1932 /**
1933  * ip6_tunnel_cleanup - free resources and unregister protocol
1934  **/
1935
1936 static void __exit ip6_tunnel_cleanup(void)
1937 {
1938         rtnl_link_unregister(&ip6_link_ops);
1939         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1940                 pr_info("%s: can't deregister ip4ip6\n", __func__);
1941
1942         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
1943                 pr_info("%s: can't deregister ip6ip6\n", __func__);
1944
1945         unregister_pernet_device(&ip6_tnl_net_ops);
1946 }
1947
1948 module_init(ip6_tunnel_init);
1949 module_exit(ip6_tunnel_cleanup);