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ipv6: fix the use of pcpu_tstats in ip6_tunnel
[~andy/linux] / 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/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 #include <linux/slab.h>
43 #include <linux/hash.h>
44 #include <linux/etherdevice.h>
45
46 #include <asm/uaccess.h>
47 #include <linux/atomic.h>
48
49 #include <net/icmp.h>
50 #include <net/ip.h>
51 #include <net/ip_tunnels.h>
52 #include <net/ipv6.h>
53 #include <net/ip6_route.h>
54 #include <net/addrconf.h>
55 #include <net/ip6_tunnel.h>
56 #include <net/xfrm.h>
57 #include <net/dsfield.h>
58 #include <net/inet_ecn.h>
59 #include <net/net_namespace.h>
60 #include <net/netns/generic.h>
61
62 MODULE_AUTHOR("Ville Nuorvala");
63 MODULE_DESCRIPTION("IPv6 tunneling device");
64 MODULE_LICENSE("GPL");
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 IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
74 #define IPV6_TCLASS_SHIFT 20
75
76 #define HASH_SIZE_SHIFT  5
77 #define HASH_SIZE (1 << HASH_SIZE_SHIFT)
78
79 static bool log_ecn_error = true;
80 module_param(log_ecn_error, bool, 0644);
81 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
82
83 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
84 {
85         u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
86
87         return hash_32(hash, HASH_SIZE_SHIFT);
88 }
89
90 static int ip6_tnl_dev_init(struct net_device *dev);
91 static void ip6_tnl_dev_setup(struct net_device *dev);
92 static struct rtnl_link_ops ip6_link_ops __read_mostly;
93
94 static int ip6_tnl_net_id __read_mostly;
95 struct ip6_tnl_net {
96         /* the IPv6 tunnel fallback device */
97         struct net_device *fb_tnl_dev;
98         /* lists for storing tunnels in use */
99         struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
100         struct ip6_tnl __rcu *tnls_wc[1];
101         struct ip6_tnl __rcu **tnls[2];
102 };
103
104 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
105 {
106         struct pcpu_tstats tmp, sum = { 0 };
107         int i;
108
109         for_each_possible_cpu(i) {
110                 unsigned int start;
111                 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
112
113                 do {
114                         start = u64_stats_fetch_begin_bh(&tstats->syncp);
115                         tmp.rx_packets = tstats->rx_packets;
116                         tmp.rx_bytes = tstats->rx_bytes;
117                         tmp.tx_packets = tstats->tx_packets;
118                         tmp.tx_bytes =  tstats->tx_bytes;
119                 } while (u64_stats_fetch_retry_bh(&tstats->syncp, start));
120
121                 sum.rx_packets += tmp.rx_packets;
122                 sum.rx_bytes   += tmp.rx_bytes;
123                 sum.tx_packets += tmp.tx_packets;
124                 sum.tx_bytes   += tmp.tx_bytes;
125         }
126         dev->stats.rx_packets = sum.rx_packets;
127         dev->stats.rx_bytes   = sum.rx_bytes;
128         dev->stats.tx_packets = sum.tx_packets;
129         dev->stats.tx_bytes   = sum.tx_bytes;
130         return &dev->stats;
131 }
132
133 /*
134  * Locking : hash tables are protected by RCU and RTNL
135  */
136
137 struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
138 {
139         struct dst_entry *dst = t->dst_cache;
140
141         if (dst && dst->obsolete &&
142             dst->ops->check(dst, t->dst_cookie) == NULL) {
143                 t->dst_cache = NULL;
144                 dst_release(dst);
145                 return NULL;
146         }
147
148         return dst;
149 }
150 EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
151
152 void ip6_tnl_dst_reset(struct ip6_tnl *t)
153 {
154         dst_release(t->dst_cache);
155         t->dst_cache = NULL;
156 }
157 EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
158
159 void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
160 {
161         struct rt6_info *rt = (struct rt6_info *) dst;
162         t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
163         dst_release(t->dst_cache);
164         t->dst_cache = dst;
165 }
166 EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
167
168 /**
169  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
170  *   @remote: the address of the tunnel exit-point
171  *   @local: the address of the tunnel entry-point
172  *
173  * Return:
174  *   tunnel matching given end-points if found,
175  *   else fallback tunnel if its device is up,
176  *   else %NULL
177  **/
178
179 #define for_each_ip6_tunnel_rcu(start) \
180         for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
181
182 static struct ip6_tnl *
183 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
184 {
185         unsigned int hash = HASH(remote, local);
186         struct ip6_tnl *t;
187         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
188
189         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
190                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
191                     ipv6_addr_equal(remote, &t->parms.raddr) &&
192                     (t->dev->flags & IFF_UP))
193                         return t;
194         }
195         t = rcu_dereference(ip6n->tnls_wc[0]);
196         if (t && (t->dev->flags & IFF_UP))
197                 return t;
198
199         return NULL;
200 }
201
202 /**
203  * ip6_tnl_bucket - get head of list matching given tunnel parameters
204  *   @p: parameters containing tunnel end-points
205  *
206  * Description:
207  *   ip6_tnl_bucket() returns the head of the list matching the
208  *   &struct in6_addr entries laddr and raddr in @p.
209  *
210  * Return: head of IPv6 tunnel list
211  **/
212
213 static struct ip6_tnl __rcu **
214 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
215 {
216         const struct in6_addr *remote = &p->raddr;
217         const struct in6_addr *local = &p->laddr;
218         unsigned int h = 0;
219         int prio = 0;
220
221         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
222                 prio = 1;
223                 h = HASH(remote, local);
224         }
225         return &ip6n->tnls[prio][h];
226 }
227
228 /**
229  * ip6_tnl_link - add tunnel to hash table
230  *   @t: tunnel to be added
231  **/
232
233 static void
234 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
235 {
236         struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
237
238         rcu_assign_pointer(t->next , rtnl_dereference(*tp));
239         rcu_assign_pointer(*tp, t);
240 }
241
242 /**
243  * ip6_tnl_unlink - remove tunnel from hash table
244  *   @t: tunnel to be removed
245  **/
246
247 static void
248 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
249 {
250         struct ip6_tnl __rcu **tp;
251         struct ip6_tnl *iter;
252
253         for (tp = ip6_tnl_bucket(ip6n, &t->parms);
254              (iter = rtnl_dereference(*tp)) != NULL;
255              tp = &iter->next) {
256                 if (t == iter) {
257                         rcu_assign_pointer(*tp, t->next);
258                         break;
259                 }
260         }
261 }
262
263 static void ip6_dev_free(struct net_device *dev)
264 {
265         free_percpu(dev->tstats);
266         free_netdev(dev);
267 }
268
269 static int ip6_tnl_create2(struct net_device *dev)
270 {
271         struct ip6_tnl *t = netdev_priv(dev);
272         struct net *net = dev_net(dev);
273         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
274         int err;
275
276         t = netdev_priv(dev);
277         err = ip6_tnl_dev_init(dev);
278         if (err < 0)
279                 goto out;
280
281         err = register_netdevice(dev);
282         if (err < 0)
283                 goto out;
284
285         strcpy(t->parms.name, dev->name);
286         dev->rtnl_link_ops = &ip6_link_ops;
287
288         dev_hold(dev);
289         ip6_tnl_link(ip6n, t);
290         return 0;
291
292 out:
293         return err;
294 }
295
296 /**
297  * ip6_tnl_create - create a new tunnel
298  *   @p: tunnel parameters
299  *   @pt: pointer to new tunnel
300  *
301  * Description:
302  *   Create tunnel matching given parameters.
303  *
304  * Return:
305  *   created tunnel or NULL
306  **/
307
308 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
309 {
310         struct net_device *dev;
311         struct ip6_tnl *t;
312         char name[IFNAMSIZ];
313         int err;
314
315         if (p->name[0])
316                 strlcpy(name, p->name, IFNAMSIZ);
317         else
318                 sprintf(name, "ip6tnl%%d");
319
320         dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup);
321         if (dev == NULL)
322                 goto failed;
323
324         dev_net_set(dev, net);
325
326         t = netdev_priv(dev);
327         t->parms = *p;
328         t->net = dev_net(dev);
329         err = ip6_tnl_create2(dev);
330         if (err < 0)
331                 goto failed_free;
332
333         return t;
334
335 failed_free:
336         ip6_dev_free(dev);
337 failed:
338         return NULL;
339 }
340
341 /**
342  * ip6_tnl_locate - find or create tunnel matching given parameters
343  *   @p: tunnel parameters
344  *   @create: != 0 if allowed to create new tunnel if no match found
345  *
346  * Description:
347  *   ip6_tnl_locate() first tries to locate an existing tunnel
348  *   based on @parms. If this is unsuccessful, but @create is set a new
349  *   tunnel device is created and registered for use.
350  *
351  * Return:
352  *   matching tunnel or NULL
353  **/
354
355 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
356                 struct __ip6_tnl_parm *p, int create)
357 {
358         const struct in6_addr *remote = &p->raddr;
359         const struct in6_addr *local = &p->laddr;
360         struct ip6_tnl __rcu **tp;
361         struct ip6_tnl *t;
362         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
363
364         for (tp = ip6_tnl_bucket(ip6n, p);
365              (t = rtnl_dereference(*tp)) != NULL;
366              tp = &t->next) {
367                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
368                     ipv6_addr_equal(remote, &t->parms.raddr))
369                         return t;
370         }
371         if (!create)
372                 return NULL;
373         return ip6_tnl_create(net, p);
374 }
375
376 /**
377  * ip6_tnl_dev_uninit - tunnel device uninitializer
378  *   @dev: the device to be destroyed
379  *
380  * Description:
381  *   ip6_tnl_dev_uninit() removes tunnel from its list
382  **/
383
384 static void
385 ip6_tnl_dev_uninit(struct net_device *dev)
386 {
387         struct ip6_tnl *t = netdev_priv(dev);
388         struct net *net = t->net;
389         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
390
391         if (dev == ip6n->fb_tnl_dev)
392                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
393         else
394                 ip6_tnl_unlink(ip6n, t);
395         ip6_tnl_dst_reset(t);
396         dev_put(dev);
397 }
398
399 /**
400  * parse_tvl_tnl_enc_lim - handle encapsulation limit option
401  *   @skb: received socket buffer
402  *
403  * Return:
404  *   0 if none was found,
405  *   else index to encapsulation limit
406  **/
407
408 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
409 {
410         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
411         __u8 nexthdr = ipv6h->nexthdr;
412         __u16 off = sizeof (*ipv6h);
413
414         while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
415                 __u16 optlen = 0;
416                 struct ipv6_opt_hdr *hdr;
417                 if (raw + off + sizeof (*hdr) > skb->data &&
418                     !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
419                         break;
420
421                 hdr = (struct ipv6_opt_hdr *) (raw + off);
422                 if (nexthdr == NEXTHDR_FRAGMENT) {
423                         struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
424                         if (frag_hdr->frag_off)
425                                 break;
426                         optlen = 8;
427                 } else if (nexthdr == NEXTHDR_AUTH) {
428                         optlen = (hdr->hdrlen + 2) << 2;
429                 } else {
430                         optlen = ipv6_optlen(hdr);
431                 }
432                 if (nexthdr == NEXTHDR_DEST) {
433                         __u16 i = off + 2;
434                         while (1) {
435                                 struct ipv6_tlv_tnl_enc_lim *tel;
436
437                                 /* No more room for encapsulation limit */
438                                 if (i + sizeof (*tel) > off + optlen)
439                                         break;
440
441                                 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
442                                 /* return index of option if found and valid */
443                                 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
444                                     tel->length == 1)
445                                         return i;
446                                 /* else jump to next option */
447                                 if (tel->type)
448                                         i += tel->length + 2;
449                                 else
450                                         i++;
451                         }
452                 }
453                 nexthdr = hdr->nexthdr;
454                 off += optlen;
455         }
456         return 0;
457 }
458 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
459
460 /**
461  * ip6_tnl_err - tunnel error handler
462  *
463  * Description:
464  *   ip6_tnl_err() should handle errors in the tunnel according
465  *   to the specifications in RFC 2473.
466  **/
467
468 static int
469 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
470             u8 *type, u8 *code, int *msg, __u32 *info, int offset)
471 {
472         const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
473         struct ip6_tnl *t;
474         int rel_msg = 0;
475         u8 rel_type = ICMPV6_DEST_UNREACH;
476         u8 rel_code = ICMPV6_ADDR_UNREACH;
477         __u32 rel_info = 0;
478         __u16 len;
479         int err = -ENOENT;
480
481         /* If the packet doesn't contain the original IPv6 header we are
482            in trouble since we might need the source address for further
483            processing of the error. */
484
485         rcu_read_lock();
486         if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr,
487                                         &ipv6h->saddr)) == NULL)
488                 goto out;
489
490         if (t->parms.proto != ipproto && t->parms.proto != 0)
491                 goto out;
492
493         err = 0;
494
495         switch (*type) {
496                 __u32 teli;
497                 struct ipv6_tlv_tnl_enc_lim *tel;
498                 __u32 mtu;
499         case ICMPV6_DEST_UNREACH:
500                 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
501                                      t->parms.name);
502                 rel_msg = 1;
503                 break;
504         case ICMPV6_TIME_EXCEED:
505                 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
506                         net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
507                                              t->parms.name);
508                         rel_msg = 1;
509                 }
510                 break;
511         case ICMPV6_PARAMPROB:
512                 teli = 0;
513                 if ((*code) == ICMPV6_HDR_FIELD)
514                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
515
516                 if (teli && teli == *info - 2) {
517                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
518                         if (tel->encap_limit == 0) {
519                                 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
520                                                      t->parms.name);
521                                 rel_msg = 1;
522                         }
523                 } else {
524                         net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
525                                              t->parms.name);
526                 }
527                 break;
528         case ICMPV6_PKT_TOOBIG:
529                 mtu = *info - offset;
530                 if (mtu < IPV6_MIN_MTU)
531                         mtu = IPV6_MIN_MTU;
532                 t->dev->mtu = mtu;
533
534                 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
535                         rel_type = ICMPV6_PKT_TOOBIG;
536                         rel_code = 0;
537                         rel_info = mtu;
538                         rel_msg = 1;
539                 }
540                 break;
541         }
542
543         *type = rel_type;
544         *code = rel_code;
545         *info = rel_info;
546         *msg = rel_msg;
547
548 out:
549         rcu_read_unlock();
550         return err;
551 }
552
553 static int
554 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
555            u8 type, u8 code, int offset, __be32 info)
556 {
557         int rel_msg = 0;
558         u8 rel_type = type;
559         u8 rel_code = code;
560         __u32 rel_info = ntohl(info);
561         int err;
562         struct sk_buff *skb2;
563         const struct iphdr *eiph;
564         struct rtable *rt;
565         struct flowi4 fl4;
566
567         err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
568                           &rel_msg, &rel_info, offset);
569         if (err < 0)
570                 return err;
571
572         if (rel_msg == 0)
573                 return 0;
574
575         switch (rel_type) {
576         case ICMPV6_DEST_UNREACH:
577                 if (rel_code != ICMPV6_ADDR_UNREACH)
578                         return 0;
579                 rel_type = ICMP_DEST_UNREACH;
580                 rel_code = ICMP_HOST_UNREACH;
581                 break;
582         case ICMPV6_PKT_TOOBIG:
583                 if (rel_code != 0)
584                         return 0;
585                 rel_type = ICMP_DEST_UNREACH;
586                 rel_code = ICMP_FRAG_NEEDED;
587                 break;
588         case NDISC_REDIRECT:
589                 rel_type = ICMP_REDIRECT;
590                 rel_code = ICMP_REDIR_HOST;
591         default:
592                 return 0;
593         }
594
595         if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
596                 return 0;
597
598         skb2 = skb_clone(skb, GFP_ATOMIC);
599         if (!skb2)
600                 return 0;
601
602         skb_dst_drop(skb2);
603
604         skb_pull(skb2, offset);
605         skb_reset_network_header(skb2);
606         eiph = ip_hdr(skb2);
607
608         /* Try to guess incoming interface */
609         rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
610                                    eiph->saddr, 0,
611                                    0, 0,
612                                    IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
613         if (IS_ERR(rt))
614                 goto out;
615
616         skb2->dev = rt->dst.dev;
617
618         /* route "incoming" packet */
619         if (rt->rt_flags & RTCF_LOCAL) {
620                 ip_rt_put(rt);
621                 rt = NULL;
622                 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
623                                            eiph->daddr, eiph->saddr,
624                                            0, 0,
625                                            IPPROTO_IPIP,
626                                            RT_TOS(eiph->tos), 0);
627                 if (IS_ERR(rt) ||
628                     rt->dst.dev->type != ARPHRD_TUNNEL) {
629                         if (!IS_ERR(rt))
630                                 ip_rt_put(rt);
631                         goto out;
632                 }
633                 skb_dst_set(skb2, &rt->dst);
634         } else {
635                 ip_rt_put(rt);
636                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
637                                    skb2->dev) ||
638                     skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
639                         goto out;
640         }
641
642         /* change mtu on this route */
643         if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
644                 if (rel_info > dst_mtu(skb_dst(skb2)))
645                         goto out;
646
647                 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info);
648         }
649         if (rel_type == ICMP_REDIRECT)
650                 skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2);
651
652         icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
653
654 out:
655         kfree_skb(skb2);
656         return 0;
657 }
658
659 static int
660 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
661            u8 type, u8 code, int offset, __be32 info)
662 {
663         int rel_msg = 0;
664         u8 rel_type = type;
665         u8 rel_code = code;
666         __u32 rel_info = ntohl(info);
667         int err;
668
669         err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
670                           &rel_msg, &rel_info, offset);
671         if (err < 0)
672                 return err;
673
674         if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
675                 struct rt6_info *rt;
676                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
677
678                 if (!skb2)
679                         return 0;
680
681                 skb_dst_drop(skb2);
682                 skb_pull(skb2, offset);
683                 skb_reset_network_header(skb2);
684
685                 /* Try to guess incoming interface */
686                 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
687                                 NULL, 0, 0);
688
689                 if (rt && rt->dst.dev)
690                         skb2->dev = rt->dst.dev;
691
692                 icmpv6_send(skb2, rel_type, rel_code, rel_info);
693
694                 ip6_rt_put(rt);
695
696                 kfree_skb(skb2);
697         }
698
699         return 0;
700 }
701
702 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
703                                        const struct ipv6hdr *ipv6h,
704                                        struct sk_buff *skb)
705 {
706         __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
707
708         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
709                 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
710
711         return IP6_ECN_decapsulate(ipv6h, skb);
712 }
713
714 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
715                                        const struct ipv6hdr *ipv6h,
716                                        struct sk_buff *skb)
717 {
718         if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
719                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
720
721         return IP6_ECN_decapsulate(ipv6h, skb);
722 }
723
724 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
725                              const struct in6_addr *laddr,
726                              const struct in6_addr *raddr)
727 {
728         struct __ip6_tnl_parm *p = &t->parms;
729         int ltype = ipv6_addr_type(laddr);
730         int rtype = ipv6_addr_type(raddr);
731         __u32 flags = 0;
732
733         if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
734                 flags = IP6_TNL_F_CAP_PER_PACKET;
735         } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
736                    rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
737                    !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
738                    (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
739                 if (ltype&IPV6_ADDR_UNICAST)
740                         flags |= IP6_TNL_F_CAP_XMIT;
741                 if (rtype&IPV6_ADDR_UNICAST)
742                         flags |= IP6_TNL_F_CAP_RCV;
743         }
744         return flags;
745 }
746 EXPORT_SYMBOL(ip6_tnl_get_cap);
747
748 /* called with rcu_read_lock() */
749 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
750                                   const struct in6_addr *laddr,
751                                   const struct in6_addr *raddr)
752 {
753         struct __ip6_tnl_parm *p = &t->parms;
754         int ret = 0;
755         struct net *net = t->net;
756
757         if ((p->flags & IP6_TNL_F_CAP_RCV) ||
758             ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
759              (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
760                 struct net_device *ldev = NULL;
761
762                 if (p->link)
763                         ldev = dev_get_by_index_rcu(net, p->link);
764
765                 if ((ipv6_addr_is_multicast(laddr) ||
766                      likely(ipv6_chk_addr(net, laddr, ldev, 0))) &&
767                     likely(!ipv6_chk_addr(net, raddr, NULL, 0)))
768                         ret = 1;
769         }
770         return ret;
771 }
772 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
773
774 /**
775  * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
776  *   @skb: received socket buffer
777  *   @protocol: ethernet protocol ID
778  *   @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN
779  *
780  * Return: 0
781  **/
782
783 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
784                        __u8 ipproto,
785                        int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
786                                                    const struct ipv6hdr *ipv6h,
787                                                    struct sk_buff *skb))
788 {
789         struct ip6_tnl *t;
790         const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
791         int err;
792
793         rcu_read_lock();
794
795         if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
796                                         &ipv6h->daddr)) != NULL) {
797                 struct pcpu_tstats *tstats;
798
799                 if (t->parms.proto != ipproto && t->parms.proto != 0) {
800                         rcu_read_unlock();
801                         goto discard;
802                 }
803
804                 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
805                         rcu_read_unlock();
806                         goto discard;
807                 }
808
809                 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
810                         t->dev->stats.rx_dropped++;
811                         rcu_read_unlock();
812                         goto discard;
813                 }
814                 skb->mac_header = skb->network_header;
815                 skb_reset_network_header(skb);
816                 skb->protocol = htons(protocol);
817                 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
818
819                 __skb_tunnel_rx(skb, t->dev, t->net);
820
821                 err = dscp_ecn_decapsulate(t, ipv6h, skb);
822                 if (unlikely(err)) {
823                         if (log_ecn_error)
824                                 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n",
825                                                      &ipv6h->saddr,
826                                                      ipv6_get_dsfield(ipv6h));
827                         if (err > 1) {
828                                 ++t->dev->stats.rx_frame_errors;
829                                 ++t->dev->stats.rx_errors;
830                                 rcu_read_unlock();
831                                 goto discard;
832                         }
833                 }
834
835                 tstats = this_cpu_ptr(t->dev->tstats);
836                 u64_stats_update_begin(&tstats->syncp);
837                 tstats->rx_packets++;
838                 tstats->rx_bytes += skb->len;
839                 u64_stats_update_end(&tstats->syncp);
840
841                 netif_rx(skb);
842
843                 rcu_read_unlock();
844                 return 0;
845         }
846         rcu_read_unlock();
847         return 1;
848
849 discard:
850         kfree_skb(skb);
851         return 0;
852 }
853
854 static int ip4ip6_rcv(struct sk_buff *skb)
855 {
856         return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
857                            ip4ip6_dscp_ecn_decapsulate);
858 }
859
860 static int ip6ip6_rcv(struct sk_buff *skb)
861 {
862         return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
863                            ip6ip6_dscp_ecn_decapsulate);
864 }
865
866 struct ipv6_tel_txoption {
867         struct ipv6_txoptions ops;
868         __u8 dst_opt[8];
869 };
870
871 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
872 {
873         memset(opt, 0, sizeof(struct ipv6_tel_txoption));
874
875         opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
876         opt->dst_opt[3] = 1;
877         opt->dst_opt[4] = encap_limit;
878         opt->dst_opt[5] = IPV6_TLV_PADN;
879         opt->dst_opt[6] = 1;
880
881         opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
882         opt->ops.opt_nflen = 8;
883 }
884
885 /**
886  * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
887  *   @t: the outgoing tunnel device
888  *   @hdr: IPv6 header from the incoming packet
889  *
890  * Description:
891  *   Avoid trivial tunneling loop by checking that tunnel exit-point
892  *   doesn't match source of incoming packet.
893  *
894  * Return:
895  *   1 if conflict,
896  *   0 else
897  **/
898
899 static inline bool
900 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
901 {
902         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
903 }
904
905 int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
906 {
907         struct __ip6_tnl_parm *p = &t->parms;
908         int ret = 0;
909         struct net *net = t->net;
910
911         if (p->flags & IP6_TNL_F_CAP_XMIT) {
912                 struct net_device *ldev = NULL;
913
914                 rcu_read_lock();
915                 if (p->link)
916                         ldev = dev_get_by_index_rcu(net, p->link);
917
918                 if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0)))
919                         pr_warn("%s xmit: Local address not yet configured!\n",
920                                 p->name);
921                 else if (!ipv6_addr_is_multicast(&p->raddr) &&
922                          unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0)))
923                         pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
924                                 p->name);
925                 else
926                         ret = 1;
927                 rcu_read_unlock();
928         }
929         return ret;
930 }
931 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
932
933 /**
934  * ip6_tnl_xmit2 - encapsulate packet and send
935  *   @skb: the outgoing socket buffer
936  *   @dev: the outgoing tunnel device
937  *   @dsfield: dscp code for outer header
938  *   @fl: flow of tunneled packet
939  *   @encap_limit: encapsulation limit
940  *   @pmtu: Path MTU is stored if packet is too big
941  *
942  * Description:
943  *   Build new header and do some sanity checks on the packet before sending
944  *   it.
945  *
946  * Return:
947  *   0 on success
948  *   -1 fail
949  *   %-EMSGSIZE message too big. return mtu in this case.
950  **/
951
952 static int ip6_tnl_xmit2(struct sk_buff *skb,
953                          struct net_device *dev,
954                          __u8 dsfield,
955                          struct flowi6 *fl6,
956                          int encap_limit,
957                          __u32 *pmtu)
958 {
959         struct ip6_tnl *t = netdev_priv(dev);
960         struct net *net = t->net;
961         struct net_device_stats *stats = &t->dev->stats;
962         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
963         struct ipv6_tel_txoption opt;
964         struct dst_entry *dst = NULL, *ndst = NULL;
965         struct net_device *tdev;
966         int mtu;
967         unsigned int max_headroom = sizeof(struct ipv6hdr);
968         u8 proto;
969         int err = -1;
970
971         if (!fl6->flowi6_mark)
972                 dst = ip6_tnl_dst_check(t);
973         if (!dst) {
974                 ndst = ip6_route_output(net, NULL, fl6);
975
976                 if (ndst->error)
977                         goto tx_err_link_failure;
978                 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
979                 if (IS_ERR(ndst)) {
980                         err = PTR_ERR(ndst);
981                         ndst = NULL;
982                         goto tx_err_link_failure;
983                 }
984                 dst = ndst;
985         }
986
987         tdev = dst->dev;
988
989         if (tdev == dev) {
990                 stats->collisions++;
991                 net_warn_ratelimited("%s: Local routing loop detected!\n",
992                                      t->parms.name);
993                 goto tx_err_dst_release;
994         }
995         mtu = dst_mtu(dst) - sizeof (*ipv6h);
996         if (encap_limit >= 0) {
997                 max_headroom += 8;
998                 mtu -= 8;
999         }
1000         if (mtu < IPV6_MIN_MTU)
1001                 mtu = IPV6_MIN_MTU;
1002         if (skb_dst(skb))
1003                 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
1004         if (skb->len > mtu) {
1005                 *pmtu = mtu;
1006                 err = -EMSGSIZE;
1007                 goto tx_err_dst_release;
1008         }
1009
1010         skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1011
1012         /*
1013          * Okay, now see if we can stuff it in the buffer as-is.
1014          */
1015         max_headroom += LL_RESERVED_SPACE(tdev);
1016
1017         if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1018             (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1019                 struct sk_buff *new_skb;
1020
1021                 if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
1022                         goto tx_err_dst_release;
1023
1024                 if (skb->sk)
1025                         skb_set_owner_w(new_skb, skb->sk);
1026                 consume_skb(skb);
1027                 skb = new_skb;
1028         }
1029         if (fl6->flowi6_mark) {
1030                 skb_dst_set(skb, dst);
1031                 ndst = NULL;
1032         } else {
1033                 skb_dst_set_noref(skb, dst);
1034         }
1035         skb->transport_header = skb->network_header;
1036
1037         proto = fl6->flowi6_proto;
1038         if (encap_limit >= 0) {
1039                 init_tel_txopt(&opt, encap_limit);
1040                 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
1041         }
1042
1043         if (likely(!skb->encapsulation)) {
1044                 skb_reset_inner_headers(skb);
1045                 skb->encapsulation = 1;
1046         }
1047
1048         skb_push(skb, sizeof(struct ipv6hdr));
1049         skb_reset_network_header(skb);
1050         ipv6h = ipv6_hdr(skb);
1051         ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel);
1052         ipv6h->hop_limit = t->parms.hop_limit;
1053         ipv6h->nexthdr = proto;
1054         ipv6h->saddr = fl6->saddr;
1055         ipv6h->daddr = fl6->daddr;
1056         ip6tunnel_xmit(skb, dev);
1057         if (ndst)
1058                 ip6_tnl_dst_store(t, ndst);
1059         return 0;
1060 tx_err_link_failure:
1061         stats->tx_carrier_errors++;
1062         dst_link_failure(skb);
1063 tx_err_dst_release:
1064         dst_release(ndst);
1065         return err;
1066 }
1067
1068 static inline int
1069 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1070 {
1071         struct ip6_tnl *t = netdev_priv(dev);
1072         const struct iphdr  *iph = ip_hdr(skb);
1073         int encap_limit = -1;
1074         struct flowi6 fl6;
1075         __u8 dsfield;
1076         __u32 mtu;
1077         int err;
1078
1079         if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) ||
1080             !ip6_tnl_xmit_ctl(t))
1081                 return -1;
1082
1083         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1084                 encap_limit = t->parms.encap_limit;
1085
1086         memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1087         fl6.flowi6_proto = IPPROTO_IPIP;
1088
1089         dsfield = ipv4_get_dsfield(iph);
1090
1091         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1092                 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1093                                           & IPV6_TCLASS_MASK;
1094         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1095                 fl6.flowi6_mark = skb->mark;
1096
1097         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1098         if (err != 0) {
1099                 /* XXX: send ICMP error even if DF is not set. */
1100                 if (err == -EMSGSIZE)
1101                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1102                                   htonl(mtu));
1103                 return -1;
1104         }
1105
1106         return 0;
1107 }
1108
1109 static inline int
1110 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1111 {
1112         struct ip6_tnl *t = netdev_priv(dev);
1113         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1114         int encap_limit = -1;
1115         __u16 offset;
1116         struct flowi6 fl6;
1117         __u8 dsfield;
1118         __u32 mtu;
1119         int err;
1120
1121         if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
1122             !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
1123                 return -1;
1124
1125         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
1126         if (offset > 0) {
1127                 struct ipv6_tlv_tnl_enc_lim *tel;
1128                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
1129                 if (tel->encap_limit == 0) {
1130                         icmpv6_send(skb, ICMPV6_PARAMPROB,
1131                                     ICMPV6_HDR_FIELD, offset + 2);
1132                         return -1;
1133                 }
1134                 encap_limit = tel->encap_limit - 1;
1135         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1136                 encap_limit = t->parms.encap_limit;
1137
1138         memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1139         fl6.flowi6_proto = IPPROTO_IPV6;
1140
1141         dsfield = ipv6_get_dsfield(ipv6h);
1142         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1143                 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1144         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1145                 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
1146         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1147                 fl6.flowi6_mark = skb->mark;
1148
1149         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1150         if (err != 0) {
1151                 if (err == -EMSGSIZE)
1152                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1153                 return -1;
1154         }
1155
1156         return 0;
1157 }
1158
1159 static netdev_tx_t
1160 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1161 {
1162         struct ip6_tnl *t = netdev_priv(dev);
1163         struct net_device_stats *stats = &t->dev->stats;
1164         int ret;
1165
1166         switch (skb->protocol) {
1167         case htons(ETH_P_IP):
1168                 ret = ip4ip6_tnl_xmit(skb, dev);
1169                 break;
1170         case htons(ETH_P_IPV6):
1171                 ret = ip6ip6_tnl_xmit(skb, dev);
1172                 break;
1173         default:
1174                 goto tx_err;
1175         }
1176
1177         if (ret < 0)
1178                 goto tx_err;
1179
1180         return NETDEV_TX_OK;
1181
1182 tx_err:
1183         stats->tx_errors++;
1184         stats->tx_dropped++;
1185         kfree_skb(skb);
1186         return NETDEV_TX_OK;
1187 }
1188
1189 static void ip6_tnl_link_config(struct ip6_tnl *t)
1190 {
1191         struct net_device *dev = t->dev;
1192         struct __ip6_tnl_parm *p = &t->parms;
1193         struct flowi6 *fl6 = &t->fl.u.ip6;
1194
1195         memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1196         memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1197
1198         /* Set up flowi template */
1199         fl6->saddr = p->laddr;
1200         fl6->daddr = p->raddr;
1201         fl6->flowi6_oif = p->link;
1202         fl6->flowlabel = 0;
1203
1204         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1205                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1206         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1207                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1208
1209         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1210         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1211
1212         if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1213                 dev->flags |= IFF_POINTOPOINT;
1214         else
1215                 dev->flags &= ~IFF_POINTOPOINT;
1216
1217         dev->iflink = p->link;
1218
1219         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1220                 int strict = (ipv6_addr_type(&p->raddr) &
1221                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1222
1223                 struct rt6_info *rt = rt6_lookup(t->net,
1224                                                  &p->raddr, &p->laddr,
1225                                                  p->link, strict);
1226
1227                 if (rt == NULL)
1228                         return;
1229
1230                 if (rt->dst.dev) {
1231                         dev->hard_header_len = rt->dst.dev->hard_header_len +
1232                                 sizeof (struct ipv6hdr);
1233
1234                         dev->mtu = rt->dst.dev->mtu - sizeof (struct ipv6hdr);
1235                         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1236                                 dev->mtu-=8;
1237
1238                         if (dev->mtu < IPV6_MIN_MTU)
1239                                 dev->mtu = IPV6_MIN_MTU;
1240                 }
1241                 ip6_rt_put(rt);
1242         }
1243 }
1244
1245 /**
1246  * ip6_tnl_change - update the tunnel parameters
1247  *   @t: tunnel to be changed
1248  *   @p: tunnel configuration parameters
1249  *
1250  * Description:
1251  *   ip6_tnl_change() updates the tunnel parameters
1252  **/
1253
1254 static int
1255 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1256 {
1257         t->parms.laddr = p->laddr;
1258         t->parms.raddr = p->raddr;
1259         t->parms.flags = p->flags;
1260         t->parms.hop_limit = p->hop_limit;
1261         t->parms.encap_limit = p->encap_limit;
1262         t->parms.flowinfo = p->flowinfo;
1263         t->parms.link = p->link;
1264         t->parms.proto = p->proto;
1265         ip6_tnl_dst_reset(t);
1266         ip6_tnl_link_config(t);
1267         return 0;
1268 }
1269
1270 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1271 {
1272         struct net *net = t->net;
1273         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1274         int err;
1275
1276         ip6_tnl_unlink(ip6n, t);
1277         synchronize_net();
1278         err = ip6_tnl_change(t, p);
1279         ip6_tnl_link(ip6n, t);
1280         netdev_state_change(t->dev);
1281         return err;
1282 }
1283
1284 static void
1285 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1286 {
1287         p->laddr = u->laddr;
1288         p->raddr = u->raddr;
1289         p->flags = u->flags;
1290         p->hop_limit = u->hop_limit;
1291         p->encap_limit = u->encap_limit;
1292         p->flowinfo = u->flowinfo;
1293         p->link = u->link;
1294         p->proto = u->proto;
1295         memcpy(p->name, u->name, sizeof(u->name));
1296 }
1297
1298 static void
1299 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1300 {
1301         u->laddr = p->laddr;
1302         u->raddr = p->raddr;
1303         u->flags = p->flags;
1304         u->hop_limit = p->hop_limit;
1305         u->encap_limit = p->encap_limit;
1306         u->flowinfo = p->flowinfo;
1307         u->link = p->link;
1308         u->proto = p->proto;
1309         memcpy(u->name, p->name, sizeof(u->name));
1310 }
1311
1312 /**
1313  * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1314  *   @dev: virtual device associated with tunnel
1315  *   @ifr: parameters passed from userspace
1316  *   @cmd: command to be performed
1317  *
1318  * Description:
1319  *   ip6_tnl_ioctl() is used for managing IPv6 tunnels
1320  *   from userspace.
1321  *
1322  *   The possible commands are the following:
1323  *     %SIOCGETTUNNEL: get tunnel parameters for device
1324  *     %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1325  *     %SIOCCHGTUNNEL: change tunnel parameters to those given
1326  *     %SIOCDELTUNNEL: delete tunnel
1327  *
1328  *   The fallback device "ip6tnl0", created during module
1329  *   initialization, can be used for creating other tunnel devices.
1330  *
1331  * Return:
1332  *   0 on success,
1333  *   %-EFAULT if unable to copy data to or from userspace,
1334  *   %-EPERM if current process hasn't %CAP_NET_ADMIN set
1335  *   %-EINVAL if passed tunnel parameters are invalid,
1336  *   %-EEXIST if changing a tunnel's parameters would cause a conflict
1337  *   %-ENODEV if attempting to change or delete a nonexisting device
1338  **/
1339
1340 static int
1341 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1342 {
1343         int err = 0;
1344         struct ip6_tnl_parm p;
1345         struct __ip6_tnl_parm p1;
1346         struct ip6_tnl *t = NULL;
1347         struct net *net = dev_net(dev);
1348         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1349
1350         switch (cmd) {
1351         case SIOCGETTUNNEL:
1352                 if (dev == ip6n->fb_tnl_dev) {
1353                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {
1354                                 err = -EFAULT;
1355                                 break;
1356                         }
1357                         ip6_tnl_parm_from_user(&p1, &p);
1358                         t = ip6_tnl_locate(net, &p1, 0);
1359                 } else {
1360                         memset(&p, 0, sizeof(p));
1361                 }
1362                 if (t == NULL)
1363                         t = netdev_priv(dev);
1364                 ip6_tnl_parm_to_user(&p, &t->parms);
1365                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
1366                         err = -EFAULT;
1367                 }
1368                 break;
1369         case SIOCADDTUNNEL:
1370         case SIOCCHGTUNNEL:
1371                 err = -EPERM;
1372                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1373                         break;
1374                 err = -EFAULT;
1375                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1376                         break;
1377                 err = -EINVAL;
1378                 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1379                     p.proto != 0)
1380                         break;
1381                 ip6_tnl_parm_from_user(&p1, &p);
1382                 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1383                 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
1384                         if (t != NULL) {
1385                                 if (t->dev != dev) {
1386                                         err = -EEXIST;
1387                                         break;
1388                                 }
1389                         } else
1390                                 t = netdev_priv(dev);
1391
1392                         err = ip6_tnl_update(t, &p1);
1393                 }
1394                 if (t) {
1395                         err = 0;
1396                         ip6_tnl_parm_to_user(&p, &t->parms);
1397                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1398                                 err = -EFAULT;
1399
1400                 } else
1401                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1402                 break;
1403         case SIOCDELTUNNEL:
1404                 err = -EPERM;
1405                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1406                         break;
1407
1408                 if (dev == ip6n->fb_tnl_dev) {
1409                         err = -EFAULT;
1410                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1411                                 break;
1412                         err = -ENOENT;
1413                         ip6_tnl_parm_from_user(&p1, &p);
1414                         t = ip6_tnl_locate(net, &p1, 0);
1415                         if (t == NULL)
1416                                 break;
1417                         err = -EPERM;
1418                         if (t->dev == ip6n->fb_tnl_dev)
1419                                 break;
1420                         dev = t->dev;
1421                 }
1422                 err = 0;
1423                 unregister_netdevice(dev);
1424                 break;
1425         default:
1426                 err = -EINVAL;
1427         }
1428         return err;
1429 }
1430
1431 /**
1432  * ip6_tnl_change_mtu - change mtu manually for tunnel device
1433  *   @dev: virtual device associated with tunnel
1434  *   @new_mtu: the new mtu
1435  *
1436  * Return:
1437  *   0 on success,
1438  *   %-EINVAL if mtu too small
1439  **/
1440
1441 static int
1442 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1443 {
1444         struct ip6_tnl *tnl = netdev_priv(dev);
1445
1446         if (tnl->parms.proto == IPPROTO_IPIP) {
1447                 if (new_mtu < 68)
1448                         return -EINVAL;
1449         } else {
1450                 if (new_mtu < IPV6_MIN_MTU)
1451                         return -EINVAL;
1452         }
1453         if (new_mtu > 0xFFF8 - dev->hard_header_len)
1454                 return -EINVAL;
1455         dev->mtu = new_mtu;
1456         return 0;
1457 }
1458
1459
1460 static const struct net_device_ops ip6_tnl_netdev_ops = {
1461         .ndo_uninit     = ip6_tnl_dev_uninit,
1462         .ndo_start_xmit = ip6_tnl_xmit,
1463         .ndo_do_ioctl   = ip6_tnl_ioctl,
1464         .ndo_change_mtu = ip6_tnl_change_mtu,
1465         .ndo_get_stats  = ip6_get_stats,
1466 };
1467
1468
1469 /**
1470  * ip6_tnl_dev_setup - setup virtual tunnel device
1471  *   @dev: virtual device associated with tunnel
1472  *
1473  * Description:
1474  *   Initialize function pointers and device parameters
1475  **/
1476
1477 static void ip6_tnl_dev_setup(struct net_device *dev)
1478 {
1479         struct ip6_tnl *t;
1480
1481         dev->netdev_ops = &ip6_tnl_netdev_ops;
1482         dev->destructor = ip6_dev_free;
1483
1484         dev->type = ARPHRD_TUNNEL6;
1485         dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
1486         dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr);
1487         t = netdev_priv(dev);
1488         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1489                 dev->mtu-=8;
1490         dev->flags |= IFF_NOARP;
1491         dev->addr_len = sizeof(struct in6_addr);
1492         dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1493         /* This perm addr will be used as interface identifier by IPv6 */
1494         dev->addr_assign_type = NET_ADDR_RANDOM;
1495         eth_random_addr(dev->perm_addr);
1496 }
1497
1498
1499 /**
1500  * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1501  *   @dev: virtual device associated with tunnel
1502  **/
1503
1504 static inline int
1505 ip6_tnl_dev_init_gen(struct net_device *dev)
1506 {
1507         struct ip6_tnl *t = netdev_priv(dev);
1508         int i;
1509
1510         t->dev = dev;
1511         t->net = dev_net(dev);
1512         dev->tstats = alloc_percpu(struct pcpu_tstats);
1513         if (!dev->tstats)
1514                 return -ENOMEM;
1515
1516         for_each_possible_cpu(i) {
1517                 struct pcpu_tstats *ip6_tnl_stats;
1518                 ip6_tnl_stats = per_cpu_ptr(dev->tstats, i);
1519                 u64_stats_init(&ip6_tnl_stats->syncp);
1520         }
1521         return 0;
1522 }
1523
1524 /**
1525  * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1526  *   @dev: virtual device associated with tunnel
1527  **/
1528
1529 static int ip6_tnl_dev_init(struct net_device *dev)
1530 {
1531         struct ip6_tnl *t = netdev_priv(dev);
1532         int err = ip6_tnl_dev_init_gen(dev);
1533
1534         if (err)
1535                 return err;
1536         ip6_tnl_link_config(t);
1537         return 0;
1538 }
1539
1540 /**
1541  * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1542  *   @dev: fallback device
1543  *
1544  * Return: 0
1545  **/
1546
1547 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1548 {
1549         struct ip6_tnl *t = netdev_priv(dev);
1550         struct net *net = dev_net(dev);
1551         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1552         int err = ip6_tnl_dev_init_gen(dev);
1553
1554         if (err)
1555                 return err;
1556
1557         t->parms.proto = IPPROTO_IPV6;
1558         dev_hold(dev);
1559
1560         ip6_tnl_link_config(t);
1561
1562         rcu_assign_pointer(ip6n->tnls_wc[0], t);
1563         return 0;
1564 }
1565
1566 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[])
1567 {
1568         u8 proto;
1569
1570         if (!data)
1571                 return 0;
1572
1573         proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1574         if (proto != IPPROTO_IPV6 &&
1575             proto != IPPROTO_IPIP &&
1576             proto != 0)
1577                 return -EINVAL;
1578
1579         return 0;
1580 }
1581
1582 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1583                                   struct __ip6_tnl_parm *parms)
1584 {
1585         memset(parms, 0, sizeof(*parms));
1586
1587         if (!data)
1588                 return;
1589
1590         if (data[IFLA_IPTUN_LINK])
1591                 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1592
1593         if (data[IFLA_IPTUN_LOCAL])
1594                 nla_memcpy(&parms->laddr, data[IFLA_IPTUN_LOCAL],
1595                            sizeof(struct in6_addr));
1596
1597         if (data[IFLA_IPTUN_REMOTE])
1598                 nla_memcpy(&parms->raddr, data[IFLA_IPTUN_REMOTE],
1599                            sizeof(struct in6_addr));
1600
1601         if (data[IFLA_IPTUN_TTL])
1602                 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1603
1604         if (data[IFLA_IPTUN_ENCAP_LIMIT])
1605                 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1606
1607         if (data[IFLA_IPTUN_FLOWINFO])
1608                 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1609
1610         if (data[IFLA_IPTUN_FLAGS])
1611                 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1612
1613         if (data[IFLA_IPTUN_PROTO])
1614                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1615 }
1616
1617 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
1618                            struct nlattr *tb[], struct nlattr *data[])
1619 {
1620         struct net *net = dev_net(dev);
1621         struct ip6_tnl *nt;
1622
1623         nt = netdev_priv(dev);
1624         ip6_tnl_netlink_parms(data, &nt->parms);
1625
1626         if (ip6_tnl_locate(net, &nt->parms, 0))
1627                 return -EEXIST;
1628
1629         return ip6_tnl_create2(dev);
1630 }
1631
1632 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
1633                               struct nlattr *data[])
1634 {
1635         struct ip6_tnl *t = netdev_priv(dev);
1636         struct __ip6_tnl_parm p;
1637         struct net *net = t->net;
1638         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1639
1640         if (dev == ip6n->fb_tnl_dev)
1641                 return -EINVAL;
1642
1643         ip6_tnl_netlink_parms(data, &p);
1644
1645         t = ip6_tnl_locate(net, &p, 0);
1646
1647         if (t) {
1648                 if (t->dev != dev)
1649                         return -EEXIST;
1650         } else
1651                 t = netdev_priv(dev);
1652
1653         return ip6_tnl_update(t, &p);
1654 }
1655
1656 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
1657 {
1658         struct net *net = dev_net(dev);
1659         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1660
1661         if (dev != ip6n->fb_tnl_dev)
1662                 unregister_netdevice_queue(dev, head);
1663 }
1664
1665 static size_t ip6_tnl_get_size(const struct net_device *dev)
1666 {
1667         return
1668                 /* IFLA_IPTUN_LINK */
1669                 nla_total_size(4) +
1670                 /* IFLA_IPTUN_LOCAL */
1671                 nla_total_size(sizeof(struct in6_addr)) +
1672                 /* IFLA_IPTUN_REMOTE */
1673                 nla_total_size(sizeof(struct in6_addr)) +
1674                 /* IFLA_IPTUN_TTL */
1675                 nla_total_size(1) +
1676                 /* IFLA_IPTUN_ENCAP_LIMIT */
1677                 nla_total_size(1) +
1678                 /* IFLA_IPTUN_FLOWINFO */
1679                 nla_total_size(4) +
1680                 /* IFLA_IPTUN_FLAGS */
1681                 nla_total_size(4) +
1682                 /* IFLA_IPTUN_PROTO */
1683                 nla_total_size(1) +
1684                 0;
1685 }
1686
1687 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
1688 {
1689         struct ip6_tnl *tunnel = netdev_priv(dev);
1690         struct __ip6_tnl_parm *parm = &tunnel->parms;
1691
1692         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1693             nla_put(skb, IFLA_IPTUN_LOCAL, sizeof(struct in6_addr),
1694                     &parm->laddr) ||
1695             nla_put(skb, IFLA_IPTUN_REMOTE, sizeof(struct in6_addr),
1696                     &parm->raddr) ||
1697             nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
1698             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
1699             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
1700             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
1701             nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
1702                 goto nla_put_failure;
1703         return 0;
1704
1705 nla_put_failure:
1706         return -EMSGSIZE;
1707 }
1708
1709 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
1710         [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
1711         [IFLA_IPTUN_LOCAL]              = { .len = sizeof(struct in6_addr) },
1712         [IFLA_IPTUN_REMOTE]             = { .len = sizeof(struct in6_addr) },
1713         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
1714         [IFLA_IPTUN_ENCAP_LIMIT]        = { .type = NLA_U8 },
1715         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
1716         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
1717         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
1718 };
1719
1720 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
1721         .kind           = "ip6tnl",
1722         .maxtype        = IFLA_IPTUN_MAX,
1723         .policy         = ip6_tnl_policy,
1724         .priv_size      = sizeof(struct ip6_tnl),
1725         .setup          = ip6_tnl_dev_setup,
1726         .validate       = ip6_tnl_validate,
1727         .newlink        = ip6_tnl_newlink,
1728         .changelink     = ip6_tnl_changelink,
1729         .dellink        = ip6_tnl_dellink,
1730         .get_size       = ip6_tnl_get_size,
1731         .fill_info      = ip6_tnl_fill_info,
1732 };
1733
1734 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
1735         .handler        = ip4ip6_rcv,
1736         .err_handler    = ip4ip6_err,
1737         .priority       =       1,
1738 };
1739
1740 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
1741         .handler        = ip6ip6_rcv,
1742         .err_handler    = ip6ip6_err,
1743         .priority       =       1,
1744 };
1745
1746 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net)
1747 {
1748         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1749         struct net_device *dev, *aux;
1750         int h;
1751         struct ip6_tnl *t;
1752         LIST_HEAD(list);
1753
1754         for_each_netdev_safe(net, dev, aux)
1755                 if (dev->rtnl_link_ops == &ip6_link_ops)
1756                         unregister_netdevice_queue(dev, &list);
1757
1758         for (h = 0; h < HASH_SIZE; h++) {
1759                 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1760                 while (t != NULL) {
1761                         /* If dev is in the same netns, it has already
1762                          * been added to the list by the previous loop.
1763                          */
1764                         if (!net_eq(dev_net(t->dev), net))
1765                                 unregister_netdevice_queue(t->dev, &list);
1766                         t = rtnl_dereference(t->next);
1767                 }
1768         }
1769
1770         unregister_netdevice_many(&list);
1771 }
1772
1773 static int __net_init ip6_tnl_init_net(struct net *net)
1774 {
1775         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1776         struct ip6_tnl *t = NULL;
1777         int err;
1778
1779         ip6n->tnls[0] = ip6n->tnls_wc;
1780         ip6n->tnls[1] = ip6n->tnls_r_l;
1781
1782         err = -ENOMEM;
1783         ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1784                                       ip6_tnl_dev_setup);
1785
1786         if (!ip6n->fb_tnl_dev)
1787                 goto err_alloc_dev;
1788         dev_net_set(ip6n->fb_tnl_dev, net);
1789         ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
1790         /* FB netdevice is special: we have one, and only one per netns.
1791          * Allowing to move it to another netns is clearly unsafe.
1792          */
1793         ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
1794
1795         err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1796         if (err < 0)
1797                 goto err_register;
1798
1799         err = register_netdev(ip6n->fb_tnl_dev);
1800         if (err < 0)
1801                 goto err_register;
1802
1803         t = netdev_priv(ip6n->fb_tnl_dev);
1804
1805         strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1806         return 0;
1807
1808 err_register:
1809         ip6_dev_free(ip6n->fb_tnl_dev);
1810 err_alloc_dev:
1811         return err;
1812 }
1813
1814 static void __net_exit ip6_tnl_exit_net(struct net *net)
1815 {
1816         rtnl_lock();
1817         ip6_tnl_destroy_tunnels(net);
1818         rtnl_unlock();
1819 }
1820
1821 static struct pernet_operations ip6_tnl_net_ops = {
1822         .init = ip6_tnl_init_net,
1823         .exit = ip6_tnl_exit_net,
1824         .id   = &ip6_tnl_net_id,
1825         .size = sizeof(struct ip6_tnl_net),
1826 };
1827
1828 /**
1829  * ip6_tunnel_init - register protocol and reserve needed resources
1830  *
1831  * Return: 0 on success
1832  **/
1833
1834 static int __init ip6_tunnel_init(void)
1835 {
1836         int  err;
1837
1838         err = register_pernet_device(&ip6_tnl_net_ops);
1839         if (err < 0)
1840                 goto out_pernet;
1841
1842         err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
1843         if (err < 0) {
1844                 pr_err("%s: can't register ip4ip6\n", __func__);
1845                 goto out_ip4ip6;
1846         }
1847
1848         err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
1849         if (err < 0) {
1850                 pr_err("%s: can't register ip6ip6\n", __func__);
1851                 goto out_ip6ip6;
1852         }
1853         err = rtnl_link_register(&ip6_link_ops);
1854         if (err < 0)
1855                 goto rtnl_link_failed;
1856
1857         return 0;
1858
1859 rtnl_link_failed:
1860         xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
1861 out_ip6ip6:
1862         xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1863 out_ip4ip6:
1864         unregister_pernet_device(&ip6_tnl_net_ops);
1865 out_pernet:
1866         return err;
1867 }
1868
1869 /**
1870  * ip6_tunnel_cleanup - free resources and unregister protocol
1871  **/
1872
1873 static void __exit ip6_tunnel_cleanup(void)
1874 {
1875         rtnl_link_unregister(&ip6_link_ops);
1876         if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1877                 pr_info("%s: can't deregister ip4ip6\n", __func__);
1878
1879         if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
1880                 pr_info("%s: can't deregister ip6ip6\n", __func__);
1881
1882         unregister_pernet_device(&ip6_tnl_net_ops);
1883 }
1884
1885 module_init(ip6_tunnel_init);
1886 module_exit(ip6_tunnel_cleanup);