?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
ip6tnl: add x-netns support
[linux-2.6.git] / net / ipv6 / ip6_tunnel.c
blobcc3bb201b8b027683d9c8a971e070705d911ed19
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
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_NETDEV("ip6tnl0");
65
66 #ifdef IP6_TNL_DEBUG
67 #define IP6_TNL_TRACE(x...) pr_debug("%s:" x "\n", __func__)
68 #else
69 #define IP6_TNL_TRACE(x...) do {;} while(0)
70 #endif
71
72 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
73 #define IPV6_TCLASS_SHIFT 20
74
75 #define HASH_SIZE_SHIFT 5
76 #define HASH_SIZE (1 << HASH_SIZE_SHIFT)
77
78 static bool log_ecn_error = true;
79 module_param(log_ecn_error, bool, 0644);
80 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
81
82 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
83 {
84 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
85
86 return hash_32(hash, HASH_SIZE_SHIFT);
87 }
88
89 static int ip6_tnl_dev_init(struct net_device *dev);
90 static void ip6_tnl_dev_setup(struct net_device *dev);
91 static struct rtnl_link_ops ip6_link_ops __read_mostly;
92
93 static int ip6_tnl_net_id __read_mostly;
94 struct ip6_tnl_net {
95 /* the IPv6 tunnel fallback device */
96 struct net_device *fb_tnl_dev;
97 /* lists for storing tunnels in use */
98 struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
99 struct ip6_tnl __rcu *tnls_wc[1];
100 struct ip6_tnl __rcu **tnls[2];
101 };
102
103 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
104 {
105 struct pcpu_tstats sum = { 0 };
106 int i;
107
108 for_each_possible_cpu(i) {
109 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
110
111 sum.rx_packets += tstats->rx_packets;
112 sum.rx_bytes += tstats->rx_bytes;
113 sum.tx_packets += tstats->tx_packets;
114 sum.tx_bytes += tstats->tx_bytes;
115 }
116 dev->stats.rx_packets = sum.rx_packets;
117 dev->stats.rx_bytes = sum.rx_bytes;
118 dev->stats.tx_packets = sum.tx_packets;
119 dev->stats.tx_bytes = sum.tx_bytes;
120 return &dev->stats;
121 }
122
123 /*
124 * Locking : hash tables are protected by RCU and RTNL
125 */
126
127 struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
128 {
129 struct dst_entry *dst = t->dst_cache;
130
131 if (dst && dst->obsolete &&
132 dst->ops->check(dst, t->dst_cookie) == NULL) {
133 t->dst_cache = NULL;
134 dst_release(dst);
135 return NULL;
136 }
137
138 return dst;
139 }
140 EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
141
142 void ip6_tnl_dst_reset(struct ip6_tnl *t)
143 {
144 dst_release(t->dst_cache);
145 t->dst_cache = NULL;
146 }
147 EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
148
149 void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
150 {
151 struct rt6_info *rt = (struct rt6_info *) dst;
152 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
153 dst_release(t->dst_cache);
154 t->dst_cache = dst;
155 }
156 EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
157
158 /**
159 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
160 * @remote: the address of the tunnel exit-point
161 * @local: the address of the tunnel entry-point
162 *
163 * Return:
164 * tunnel matching given end-points if found,
165 * else fallback tunnel if its device is up,
166 * else %NULL
167 **/
168
169 #define for_each_ip6_tunnel_rcu(start) \
170 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
171
172 static struct ip6_tnl *
173 ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
174 {
175 unsigned int hash = HASH(remote, local);
176 struct ip6_tnl *t;
177 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
178
179 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
180 if (ipv6_addr_equal(local, &t->parms.laddr) &&
181 ipv6_addr_equal(remote, &t->parms.raddr) &&
182 (t->dev->flags & IFF_UP))
183 return t;
184 }
185 t = rcu_dereference(ip6n->tnls_wc[0]);
186 if (t && (t->dev->flags & IFF_UP))
187 return t;
188
189 return NULL;
190 }
191
192 /**
193 * ip6_tnl_bucket - get head of list matching given tunnel parameters
194 * @p: parameters containing tunnel end-points
195 *
196 * Description:
197 * ip6_tnl_bucket() returns the head of the list matching the
198 * &struct in6_addr entries laddr and raddr in @p.
199 *
200 * Return: head of IPv6 tunnel list
201 **/
202
203 static struct ip6_tnl __rcu **
204 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
205 {
206 const struct in6_addr *remote = &p->raddr;
207 const struct in6_addr *local = &p->laddr;
208 unsigned int h = 0;
209 int prio = 0;
210
211 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
212 prio = 1;
213 h = HASH(remote, local);
214 }
215 return &ip6n->tnls[prio][h];
216 }
217
218 /**
219 * ip6_tnl_link - add tunnel to hash table
220 * @t: tunnel to be added
221 **/
222
223 static void
224 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
225 {
226 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
227
228 rcu_assign_pointer(t->next , rtnl_dereference(*tp));
229 rcu_assign_pointer(*tp, t);
230 }
231
232 /**
233 * ip6_tnl_unlink - remove tunnel from hash table
234 * @t: tunnel to be removed
235 **/
236
237 static void
238 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
239 {
240 struct ip6_tnl __rcu **tp;
241 struct ip6_tnl *iter;
242
243 for (tp = ip6_tnl_bucket(ip6n, &t->parms);
244 (iter = rtnl_dereference(*tp)) != NULL;
245 tp = &iter->next) {
246 if (t == iter) {
247 rcu_assign_pointer(*tp, t->next);
248 break;
249 }
250 }
251 }
252
253 static void ip6_dev_free(struct net_device *dev)
254 {
255 free_percpu(dev->tstats);
256 free_netdev(dev);
257 }
258
259 static int ip6_tnl_create2(struct net_device *dev)
260 {
261 struct ip6_tnl *t = netdev_priv(dev);
262 struct net *net = dev_net(dev);
263 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
264 int err;
265
266 t = netdev_priv(dev);
267 err = ip6_tnl_dev_init(dev);
268 if (err < 0)
269 goto out;
270
271 err = register_netdevice(dev);
272 if (err < 0)
273 goto out;
274
275 strcpy(t->parms.name, dev->name);
276 dev->rtnl_link_ops = &ip6_link_ops;
277
278 dev_hold(dev);
279 ip6_tnl_link(ip6n, t);
280 return 0;
281
282 out:
283 return err;
284 }
285
286 /**
287 * ip6_tnl_create - create a new tunnel
288 * @p: tunnel parameters
289 * @pt: pointer to new tunnel
290 *
291 * Description:
292 * Create tunnel matching given parameters.
293 *
294 * Return:
295 * created tunnel or NULL
296 **/
297
298 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
299 {
300 struct net_device *dev;
301 struct ip6_tnl *t;
302 char name[IFNAMSIZ];
303 int err;
304
305 if (p->name[0])
306 strlcpy(name, p->name, IFNAMSIZ);
307 else
308 sprintf(name, "ip6tnl%%d");
309
310 dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup);
311 if (dev == NULL)
312 goto failed;
313
314 dev_net_set(dev, net);
315
316 t = netdev_priv(dev);
317 t->parms = *p;
318 t->net = dev_net(dev);
319 err = ip6_tnl_create2(dev);
320 if (err < 0)
321 goto failed_free;
322
323 return t;
324
325 failed_free:
326 ip6_dev_free(dev);
327 failed:
328 return NULL;
329 }
330
331 /**
332 * ip6_tnl_locate - find or create tunnel matching given parameters
333 * @p: tunnel parameters
334 * @create: != 0 if allowed to create new tunnel if no match found
335 *
336 * Description:
337 * ip6_tnl_locate() first tries to locate an existing tunnel
338 * based on @parms. If this is unsuccessful, but @create is set a new
339 * tunnel device is created and registered for use.
340 *
341 * Return:
342 * matching tunnel or NULL
343 **/
344
345 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
346 struct __ip6_tnl_parm *p, int create)
347 {
348 const struct in6_addr *remote = &p->raddr;
349 const struct in6_addr *local = &p->laddr;
350 struct ip6_tnl __rcu **tp;
351 struct ip6_tnl *t;
352 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
353
354 for (tp = ip6_tnl_bucket(ip6n, p);
355 (t = rtnl_dereference(*tp)) != NULL;
356 tp = &t->next) {
357 if (ipv6_addr_equal(local, &t->parms.laddr) &&
358 ipv6_addr_equal(remote, &t->parms.raddr))
359 return t;
360 }
361 if (!create)
362 return NULL;
363 return ip6_tnl_create(net, p);
364 }
365
366 /**
367 * ip6_tnl_dev_uninit - tunnel device uninitializer
368 * @dev: the device to be destroyed
369 *
370 * Description:
371 * ip6_tnl_dev_uninit() removes tunnel from its list
372 **/
373
374 static void
375 ip6_tnl_dev_uninit(struct net_device *dev)
376 {
377 struct ip6_tnl *t = netdev_priv(dev);
378 struct net *net = t->net;
379 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
380
381 if (dev == ip6n->fb_tnl_dev)
382 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
383 else
384 ip6_tnl_unlink(ip6n, t);
385 ip6_tnl_dst_reset(t);
386 dev_put(dev);
387 }
388
389 /**
390 * parse_tvl_tnl_enc_lim - handle encapsulation limit option
391 * @skb: received socket buffer
392 *
393 * Return:
394 * 0 if none was found,
395 * else index to encapsulation limit
396 **/
397
398 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
399 {
400 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) raw;
401 __u8 nexthdr = ipv6h->nexthdr;
402 __u16 off = sizeof (*ipv6h);
403
404 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
405 __u16 optlen = 0;
406 struct ipv6_opt_hdr *hdr;
407 if (raw + off + sizeof (*hdr) > skb->data &&
408 !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
409 break;
410
411 hdr = (struct ipv6_opt_hdr *) (raw + off);
412 if (nexthdr == NEXTHDR_FRAGMENT) {
413 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
414 if (frag_hdr->frag_off)
415 break;
416 optlen = 8;
417 } else if (nexthdr == NEXTHDR_AUTH) {
418 optlen = (hdr->hdrlen + 2) << 2;
419 } else {
420 optlen = ipv6_optlen(hdr);
421 }
422 if (nexthdr == NEXTHDR_DEST) {
423 __u16 i = off + 2;
424 while (1) {
425 struct ipv6_tlv_tnl_enc_lim *tel;
426
427 /* No more room for encapsulation limit */
428 if (i + sizeof (*tel) > off + optlen)
429 break;
430
431 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
432 /* return index of option if found and valid */
433 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
434 tel->length == 1)
435 return i;
436 /* else jump to next option */
437 if (tel->type)
438 i += tel->length + 2;
439 else
440 i++;
441 }
442 }
443 nexthdr = hdr->nexthdr;
444 off += optlen;
445 }
446 return 0;
447 }
448 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
449
450 /**
451 * ip6_tnl_err - tunnel error handler
452 *
453 * Description:
454 * ip6_tnl_err() should handle errors in the tunnel according
455 * to the specifications in RFC 2473.
456 **/
457
458 static int
459 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
460 u8 *type, u8 *code, int *msg, __u32 *info, int offset)
461 {
462 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data;
463 struct ip6_tnl *t;
464 int rel_msg = 0;
465 u8 rel_type = ICMPV6_DEST_UNREACH;
466 u8 rel_code = ICMPV6_ADDR_UNREACH;
467 __u32 rel_info = 0;
468 __u16 len;
469 int err = -ENOENT;
470
471 /* If the packet doesn't contain the original IPv6 header we are
472 in trouble since we might need the source address for further
473 processing of the error. */
474
475 rcu_read_lock();
476 if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr,
477 &ipv6h->saddr)) == NULL)
478 goto out;
479
480 if (t->parms.proto != ipproto && t->parms.proto != 0)
481 goto out;
482
483 err = 0;
484
485 switch (*type) {
486 __u32 teli;
487 struct ipv6_tlv_tnl_enc_lim *tel;
488 __u32 mtu;
489 case ICMPV6_DEST_UNREACH:
490 net_warn_ratelimited("%s: Path to destination invalid or inactive!\n",
491 t->parms.name);
492 rel_msg = 1;
493 break;
494 case ICMPV6_TIME_EXCEED:
495 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
496 net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
497 t->parms.name);
498 rel_msg = 1;
499 }
500 break;
501 case ICMPV6_PARAMPROB:
502 teli = 0;
503 if ((*code) == ICMPV6_HDR_FIELD)
504 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
505
506 if (teli && teli == *info - 2) {
507 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
508 if (tel->encap_limit == 0) {
509 net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
510 t->parms.name);
511 rel_msg = 1;
512 }
513 } else {
514 net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
515 t->parms.name);
516 }
517 break;
518 case ICMPV6_PKT_TOOBIG:
519 mtu = *info - offset;
520 if (mtu < IPV6_MIN_MTU)
521 mtu = IPV6_MIN_MTU;
522 t->dev->mtu = mtu;
523
524 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
525 rel_type = ICMPV6_PKT_TOOBIG;
526 rel_code = 0;
527 rel_info = mtu;
528 rel_msg = 1;
529 }
530 break;
531 }
532
533 *type = rel_type;
534 *code = rel_code;
535 *info = rel_info;
536 *msg = rel_msg;
537
538 out:
539 rcu_read_unlock();
540 return err;
541 }
542
543 static int
544 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
545 u8 type, u8 code, int offset, __be32 info)
546 {
547 int rel_msg = 0;
548 u8 rel_type = type;
549 u8 rel_code = code;
550 __u32 rel_info = ntohl(info);
551 int err;
552 struct sk_buff *skb2;
553 const struct iphdr *eiph;
554 struct rtable *rt;
555 struct flowi4 fl4;
556
557 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
558 &rel_msg, &rel_info, offset);
559 if (err < 0)
560 return err;
561
562 if (rel_msg == 0)
563 return 0;
564
565 switch (rel_type) {
566 case ICMPV6_DEST_UNREACH:
567 if (rel_code != ICMPV6_ADDR_UNREACH)
568 return 0;
569 rel_type = ICMP_DEST_UNREACH;
570 rel_code = ICMP_HOST_UNREACH;
571 break;
572 case ICMPV6_PKT_TOOBIG:
573 if (rel_code != 0)
574 return 0;
575 rel_type = ICMP_DEST_UNREACH;
576 rel_code = ICMP_FRAG_NEEDED;
577 break;
578 case NDISC_REDIRECT:
579 rel_type = ICMP_REDIRECT;
580 rel_code = ICMP_REDIR_HOST;
581 default:
582 return 0;
583 }
584
585 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
586 return 0;
587
588 skb2 = skb_clone(skb, GFP_ATOMIC);
589 if (!skb2)
590 return 0;
591
592 skb_dst_drop(skb2);
593
594 skb_pull(skb2, offset);
595 skb_reset_network_header(skb2);
596 eiph = ip_hdr(skb2);
597
598 /* Try to guess incoming interface */
599 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
600 eiph->saddr, 0,
601 0, 0,
602 IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
603 if (IS_ERR(rt))
604 goto out;
605
606 skb2->dev = rt->dst.dev;
607
608 /* route "incoming" packet */
609 if (rt->rt_flags & RTCF_LOCAL) {
610 ip_rt_put(rt);
611 rt = NULL;
612 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
613 eiph->daddr, eiph->saddr,
614 0, 0,
615 IPPROTO_IPIP,
616 RT_TOS(eiph->tos), 0);
617 if (IS_ERR(rt) ||
618 rt->dst.dev->type != ARPHRD_TUNNEL) {
619 if (!IS_ERR(rt))
620 ip_rt_put(rt);
621 goto out;
622 }
623 skb_dst_set(skb2, &rt->dst);
624 } else {
625 ip_rt_put(rt);
626 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
627 skb2->dev) ||
628 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL)
629 goto out;
630 }
631
632 /* change mtu on this route */
633 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
634 if (rel_info > dst_mtu(skb_dst(skb2)))
635 goto out;
636
637 skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info);
638 }
639 if (rel_type == ICMP_REDIRECT)
640 skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2);
641
642 icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
643
644 out:
645 kfree_skb(skb2);
646 return 0;
647 }
648
649 static int
650 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
651 u8 type, u8 code, int offset, __be32 info)
652 {
653 int rel_msg = 0;
654 u8 rel_type = type;
655 u8 rel_code = code;
656 __u32 rel_info = ntohl(info);
657 int err;
658
659 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
660 &rel_msg, &rel_info, offset);
661 if (err < 0)
662 return err;
663
664 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
665 struct rt6_info *rt;
666 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
667
668 if (!skb2)
669 return 0;
670
671 skb_dst_drop(skb2);
672 skb_pull(skb2, offset);
673 skb_reset_network_header(skb2);
674
675 /* Try to guess incoming interface */
676 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
677 NULL, 0, 0);
678
679 if (rt && rt->dst.dev)
680 skb2->dev = rt->dst.dev;
681
682 icmpv6_send(skb2, rel_type, rel_code, rel_info);
683
684 ip6_rt_put(rt);
685
686 kfree_skb(skb2);
687 }
688
689 return 0;
690 }
691
692 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
693 const struct ipv6hdr *ipv6h,
694 struct sk_buff *skb)
695 {
696 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
697
698 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
699 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
700
701 return IP6_ECN_decapsulate(ipv6h, skb);
702 }
703
704 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
705 const struct ipv6hdr *ipv6h,
706 struct sk_buff *skb)
707 {
708 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
709 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
710
711 return IP6_ECN_decapsulate(ipv6h, skb);
712 }
713
714 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
715 const struct in6_addr *laddr,
716 const struct in6_addr *raddr)
717 {
718 struct __ip6_tnl_parm *p = &t->parms;
719 int ltype = ipv6_addr_type(laddr);
720 int rtype = ipv6_addr_type(raddr);
721 __u32 flags = 0;
722
723 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
724 flags = IP6_TNL_F_CAP_PER_PACKET;
725 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
726 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
727 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
728 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
729 if (ltype&IPV6_ADDR_UNICAST)
730 flags |= IP6_TNL_F_CAP_XMIT;
731 if (rtype&IPV6_ADDR_UNICAST)
732 flags |= IP6_TNL_F_CAP_RCV;
733 }
734 return flags;
735 }
736 EXPORT_SYMBOL(ip6_tnl_get_cap);
737
738 /* called with rcu_read_lock() */
739 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
740 const struct in6_addr *laddr,
741 const struct in6_addr *raddr)
742 {
743 struct __ip6_tnl_parm *p = &t->parms;
744 int ret = 0;
745 struct net *net = t->net;
746
747 if ((p->flags & IP6_TNL_F_CAP_RCV) ||
748 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
749 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
750 struct net_device *ldev = NULL;
751
752 if (p->link)
753 ldev = dev_get_by_index_rcu(net, p->link);
754
755 if ((ipv6_addr_is_multicast(laddr) ||
756 likely(ipv6_chk_addr(net, laddr, ldev, 0))) &&
757 likely(!ipv6_chk_addr(net, raddr, NULL, 0)))
758 ret = 1;
759 }
760 return ret;
761 }
762 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
763
764 /**
765 * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
766 * @skb: received socket buffer
767 * @protocol: ethernet protocol ID
768 * @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN
769 *
770 * Return: 0
771 **/
772
773 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
774 __u8 ipproto,
775 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
776 const struct ipv6hdr *ipv6h,
777 struct sk_buff *skb))
778 {
779 struct ip6_tnl *t;
780 const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
781 int err;
782
783 rcu_read_lock();
784
785 if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
786 &ipv6h->daddr)) != NULL) {
787 struct pcpu_tstats *tstats;
788
789 if (t->parms.proto != ipproto && t->parms.proto != 0) {
790 rcu_read_unlock();
791 goto discard;
792 }
793
794 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
795 rcu_read_unlock();
796 goto discard;
797 }
798
799 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
800 t->dev->stats.rx_dropped++;
801 rcu_read_unlock();
802 goto discard;
803 }
804 secpath_reset(skb);
805 skb->mac_header = skb->network_header;
806 skb_reset_network_header(skb);
807 skb->protocol = htons(protocol);
808 skb->pkt_type = PACKET_HOST;
809 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
810
811 __skb_tunnel_rx(skb, t->dev);
812
813 err = dscp_ecn_decapsulate(t, ipv6h, skb);
814 if (unlikely(err)) {
815 if (log_ecn_error)
816 net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n",
817 &ipv6h->saddr,
818 ipv6_get_dsfield(ipv6h));
819 if (err > 1) {
820 ++t->dev->stats.rx_frame_errors;
821 ++t->dev->stats.rx_errors;
822 rcu_read_unlock();
823 goto discard;
824 }
825 }
826
827 tstats = this_cpu_ptr(t->dev->tstats);
828 tstats->rx_packets++;
829 tstats->rx_bytes += skb->len;
830
831 if (!net_eq(t->net, dev_net(t->dev)))
832 skb_scrub_packet(skb);
833
834 netif_rx(skb);
835
836 rcu_read_unlock();
837 return 0;
838 }
839 rcu_read_unlock();
840 return 1;
841
842 discard:
843 kfree_skb(skb);
844 return 0;
845 }
846
847 static int ip4ip6_rcv(struct sk_buff *skb)
848 {
849 return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
850 ip4ip6_dscp_ecn_decapsulate);
851 }
852
853 static int ip6ip6_rcv(struct sk_buff *skb)
854 {
855 return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
856 ip6ip6_dscp_ecn_decapsulate);
857 }
858
859 struct ipv6_tel_txoption {
860 struct ipv6_txoptions ops;
861 __u8 dst_opt[8];
862 };
863
864 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
865 {
866 memset(opt, 0, sizeof(struct ipv6_tel_txoption));
867
868 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
869 opt->dst_opt[3] = 1;
870 opt->dst_opt[4] = encap_limit;
871 opt->dst_opt[5] = IPV6_TLV_PADN;
872 opt->dst_opt[6] = 1;
873
874 opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt;
875 opt->ops.opt_nflen = 8;
876 }
877
878 /**
879 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
880 * @t: the outgoing tunnel device
881 * @hdr: IPv6 header from the incoming packet
882 *
883 * Description:
884 * Avoid trivial tunneling loop by checking that tunnel exit-point
885 * doesn't match source of incoming packet.
886 *
887 * Return:
888 * 1 if conflict,
889 * 0 else
890 **/
891
892 static inline bool
893 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
894 {
895 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
896 }
897
898 int ip6_tnl_xmit_ctl(struct ip6_tnl *t)
899 {
900 struct __ip6_tnl_parm *p = &t->parms;
901 int ret = 0;
902 struct net *net = t->net;
903
904 if (p->flags & IP6_TNL_F_CAP_XMIT) {
905 struct net_device *ldev = NULL;
906
907 rcu_read_lock();
908 if (p->link)
909 ldev = dev_get_by_index_rcu(net, p->link);
910
911 if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0)))
912 pr_warn("%s xmit: Local address not yet configured!\n",
913 p->name);
914 else if (!ipv6_addr_is_multicast(&p->raddr) &&
915 unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0)))
916 pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
917 p->name);
918 else
919 ret = 1;
920 rcu_read_unlock();
921 }
922 return ret;
923 }
924 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
925
926 /**
927 * ip6_tnl_xmit2 - encapsulate packet and send
928 * @skb: the outgoing socket buffer
929 * @dev: the outgoing tunnel device
930 * @dsfield: dscp code for outer header
931 * @fl: flow of tunneled packet
932 * @encap_limit: encapsulation limit
933 * @pmtu: Path MTU is stored if packet is too big
934 *
935 * Description:
936 * Build new header and do some sanity checks on the packet before sending
937 * it.
938 *
939 * Return:
940 * 0 on success
941 * -1 fail
942 * %-EMSGSIZE message too big. return mtu in this case.
943 **/
944
945 static int ip6_tnl_xmit2(struct sk_buff *skb,
946 struct net_device *dev,
947 __u8 dsfield,
948 struct flowi6 *fl6,
949 int encap_limit,
950 __u32 *pmtu)
951 {
952 struct ip6_tnl *t = netdev_priv(dev);
953 struct net *net = t->net;
954 struct net_device_stats *stats = &t->dev->stats;
955 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
956 struct ipv6_tel_txoption opt;
957 struct dst_entry *dst = NULL, *ndst = NULL;
958 struct net_device *tdev;
959 int mtu;
960 unsigned int max_headroom = sizeof(struct ipv6hdr);
961 u8 proto;
962 int err = -1;
963
964 if (!fl6->flowi6_mark)
965 dst = ip6_tnl_dst_check(t);
966 if (!dst) {
967 ndst = ip6_route_output(net, NULL, fl6);
968
969 if (ndst->error)
970 goto tx_err_link_failure;
971 ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0);
972 if (IS_ERR(ndst)) {
973 err = PTR_ERR(ndst);
974 ndst = NULL;
975 goto tx_err_link_failure;
976 }
977 dst = ndst;
978 }
979
980 tdev = dst->dev;
981
982 if (tdev == dev) {
983 stats->collisions++;
984 net_warn_ratelimited("%s: Local routing loop detected!\n",
985 t->parms.name);
986 goto tx_err_dst_release;
987 }
988 mtu = dst_mtu(dst) - sizeof (*ipv6h);
989 if (encap_limit >= 0) {
990 max_headroom += 8;
991 mtu -= 8;
992 }
993 if (mtu < IPV6_MIN_MTU)
994 mtu = IPV6_MIN_MTU;
995 if (skb_dst(skb))
996 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
997 if (skb->len > mtu) {
998 *pmtu = mtu;
999 err = -EMSGSIZE;
1000 goto tx_err_dst_release;
1001 }
1002
1003 if (!net_eq(t->net, dev_net(dev)))
1004 skb_scrub_packet(skb);
1005
1006 /*
1007 * Okay, now see if we can stuff it in the buffer as-is.
1008 */
1009 max_headroom += LL_RESERVED_SPACE(tdev);
1010
1011 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1012 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1013 struct sk_buff *new_skb;
1014
1015 if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
1016 goto tx_err_dst_release;
1017
1018 if (skb->sk)
1019 skb_set_owner_w(new_skb, skb->sk);
1020 consume_skb(skb);
1021 skb = new_skb;
1022 }
1023 skb_dst_drop(skb);
1024 if (fl6->flowi6_mark) {
1025 skb_dst_set(skb, dst);
1026 ndst = NULL;
1027 } else {
1028 skb_dst_set_noref(skb, dst);
1029 }
1030 skb->transport_header = skb->network_header;
1031
1032 proto = fl6->flowi6_proto;
1033 if (encap_limit >= 0) {
1034 init_tel_txopt(&opt, encap_limit);
1035 ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL);
1036 }
1037 skb_push(skb, sizeof(struct ipv6hdr));
1038 skb_reset_network_header(skb);
1039 ipv6h = ipv6_hdr(skb);
1040 ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel);
1041 ipv6h->hop_limit = t->parms.hop_limit;
1042 ipv6h->nexthdr = proto;
1043 ipv6h->saddr = fl6->saddr;
1044 ipv6h->daddr = fl6->daddr;
1045 ip6tunnel_xmit(skb, dev);
1046 if (ndst)
1047 ip6_tnl_dst_store(t, ndst);
1048 return 0;
1049 tx_err_link_failure:
1050 stats->tx_carrier_errors++;
1051 dst_link_failure(skb);
1052 tx_err_dst_release:
1053 dst_release(ndst);
1054 return err;
1055 }
1056
1057 static inline int
1058 ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1059 {
1060 struct ip6_tnl *t = netdev_priv(dev);
1061 const struct iphdr *iph = ip_hdr(skb);
1062 int encap_limit = -1;
1063 struct flowi6 fl6;
1064 __u8 dsfield;
1065 __u32 mtu;
1066 int err;
1067
1068 if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) ||
1069 !ip6_tnl_xmit_ctl(t))
1070 return -1;
1071
1072 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1073 encap_limit = t->parms.encap_limit;
1074
1075 memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1076 fl6.flowi6_proto = IPPROTO_IPIP;
1077
1078 dsfield = ipv4_get_dsfield(iph);
1079
1080 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1081 fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
1082 & IPV6_TCLASS_MASK;
1083 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1084 fl6.flowi6_mark = skb->mark;
1085
1086 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1087 if (err != 0) {
1088 /* XXX: send ICMP error even if DF is not set. */
1089 if (err == -EMSGSIZE)
1090 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1091 htonl(mtu));
1092 return -1;
1093 }
1094
1095 return 0;
1096 }
1097
1098 static inline int
1099 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1100 {
1101 struct ip6_tnl *t = netdev_priv(dev);
1102 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
1103 int encap_limit = -1;
1104 __u16 offset;
1105 struct flowi6 fl6;
1106 __u8 dsfield;
1107 __u32 mtu;
1108 int err;
1109
1110 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
1111 !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
1112 return -1;
1113
1114 offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
1115 if (offset > 0) {
1116 struct ipv6_tlv_tnl_enc_lim *tel;
1117 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
1118 if (tel->encap_limit == 0) {
1119 icmpv6_send(skb, ICMPV6_PARAMPROB,
1120 ICMPV6_HDR_FIELD, offset + 2);
1121 return -1;
1122 }
1123 encap_limit = tel->encap_limit - 1;
1124 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1125 encap_limit = t->parms.encap_limit;
1126
1127 memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6));
1128 fl6.flowi6_proto = IPPROTO_IPV6;
1129
1130 dsfield = ipv6_get_dsfield(ipv6h);
1131 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1132 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
1133 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1134 fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
1135 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1136 fl6.flowi6_mark = skb->mark;
1137
1138 err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
1139 if (err != 0) {
1140 if (err == -EMSGSIZE)
1141 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1142 return -1;
1143 }
1144
1145 return 0;
1146 }
1147
1148 static netdev_tx_t
1149 ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
1150 {
1151 struct ip6_tnl *t = netdev_priv(dev);
1152 struct net_device_stats *stats = &t->dev->stats;
1153 int ret;
1154
1155 switch (skb->protocol) {
1156 case htons(ETH_P_IP):
1157 ret = ip4ip6_tnl_xmit(skb, dev);
1158 break;
1159 case htons(ETH_P_IPV6):
1160 ret = ip6ip6_tnl_xmit(skb, dev);
1161 break;
1162 default:
1163 goto tx_err;
1164 }
1165
1166 if (ret < 0)
1167 goto tx_err;
1168
1169 return NETDEV_TX_OK;
1170
1171 tx_err:
1172 stats->tx_errors++;
1173 stats->tx_dropped++;
1174 kfree_skb(skb);
1175 return NETDEV_TX_OK;
1176 }
1177
1178 static void ip6_tnl_link_config(struct ip6_tnl *t)
1179 {
1180 struct net_device *dev = t->dev;
1181 struct __ip6_tnl_parm *p = &t->parms;
1182 struct flowi6 *fl6 = &t->fl.u.ip6;
1183
1184 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1185 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1186
1187 /* Set up flowi template */
1188 fl6->saddr = p->laddr;
1189 fl6->daddr = p->raddr;
1190 fl6->flowi6_oif = p->link;
1191 fl6->flowlabel = 0;
1192
1193 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1194 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1195 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1196 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1197
1198 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1199 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1200
1201 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1202 dev->flags |= IFF_POINTOPOINT;
1203 else
1204 dev->flags &= ~IFF_POINTOPOINT;
1205
1206 dev->iflink = p->link;
1207
1208 if (p->flags & IP6_TNL_F_CAP_XMIT) {
1209 int strict = (ipv6_addr_type(&p->raddr) &
1210 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1211
1212 struct rt6_info *rt = rt6_lookup(t->net,
1213 &p->raddr, &p->laddr,
1214 p->link, strict);
1215
1216 if (rt == NULL)
1217 return;
1218
1219 if (rt->dst.dev) {
1220 dev->hard_header_len = rt->dst.dev->hard_header_len +
1221 sizeof (struct ipv6hdr);
1222
1223 dev->mtu = rt->dst.dev->mtu - sizeof (struct ipv6hdr);
1224 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1225 dev->mtu-=8;
1226
1227 if (dev->mtu < IPV6_MIN_MTU)
1228 dev->mtu = IPV6_MIN_MTU;
1229 }
1230 ip6_rt_put(rt);
1231 }
1232 }
1233
1234 /**
1235 * ip6_tnl_change - update the tunnel parameters
1236 * @t: tunnel to be changed
1237 * @p: tunnel configuration parameters
1238 *
1239 * Description:
1240 * ip6_tnl_change() updates the tunnel parameters
1241 **/
1242
1243 static int
1244 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1245 {
1246 t->parms.laddr = p->laddr;
1247 t->parms.raddr = p->raddr;
1248 t->parms.flags = p->flags;
1249 t->parms.hop_limit = p->hop_limit;
1250 t->parms.encap_limit = p->encap_limit;
1251 t->parms.flowinfo = p->flowinfo;
1252 t->parms.link = p->link;
1253 t->parms.proto = p->proto;
1254 ip6_tnl_dst_reset(t);
1255 ip6_tnl_link_config(t);
1256 return 0;
1257 }
1258
1259 static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1260 {
1261 struct net *net = t->net;
1262 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1263 int err;
1264
1265 ip6_tnl_unlink(ip6n, t);
1266 synchronize_net();
1267 err = ip6_tnl_change(t, p);
1268 ip6_tnl_link(ip6n, t);
1269 netdev_state_change(t->dev);
1270 return err;
1271 }
1272
1273 static void
1274 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1275 {
1276 p->laddr = u->laddr;
1277 p->raddr = u->raddr;
1278 p->flags = u->flags;
1279 p->hop_limit = u->hop_limit;
1280 p->encap_limit = u->encap_limit;
1281 p->flowinfo = u->flowinfo;
1282 p->link = u->link;
1283 p->proto = u->proto;
1284 memcpy(p->name, u->name, sizeof(u->name));
1285 }
1286
1287 static void
1288 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1289 {
1290 u->laddr = p->laddr;
1291 u->raddr = p->raddr;
1292 u->flags = p->flags;
1293 u->hop_limit = p->hop_limit;
1294 u->encap_limit = p->encap_limit;
1295 u->flowinfo = p->flowinfo;
1296 u->link = p->link;
1297 u->proto = p->proto;
1298 memcpy(u->name, p->name, sizeof(u->name));
1299 }
1300
1301 /**
1302 * ip6_tnl_ioctl - configure ipv6 tunnels from userspace
1303 * @dev: virtual device associated with tunnel
1304 * @ifr: parameters passed from userspace
1305 * @cmd: command to be performed
1306 *
1307 * Description:
1308 * ip6_tnl_ioctl() is used for managing IPv6 tunnels
1309 * from userspace.
1310 *
1311 * The possible commands are the following:
1312 * %SIOCGETTUNNEL: get tunnel parameters for device
1313 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1314 * %SIOCCHGTUNNEL: change tunnel parameters to those given
1315 * %SIOCDELTUNNEL: delete tunnel
1316 *
1317 * The fallback device "ip6tnl0", created during module
1318 * initialization, can be used for creating other tunnel devices.
1319 *
1320 * Return:
1321 * 0 on success,
1322 * %-EFAULT if unable to copy data to or from userspace,
1323 * %-EPERM if current process hasn't %CAP_NET_ADMIN set
1324 * %-EINVAL if passed tunnel parameters are invalid,
1325 * %-EEXIST if changing a tunnel's parameters would cause a conflict
1326 * %-ENODEV if attempting to change or delete a nonexisting device
1327 **/
1328
1329 static int
1330 ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1331 {
1332 int err = 0;
1333 struct ip6_tnl_parm p;
1334 struct __ip6_tnl_parm p1;
1335 struct ip6_tnl *t = NULL;
1336 struct net *net = dev_net(dev);
1337 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1338
1339 switch (cmd) {
1340 case SIOCGETTUNNEL:
1341 if (dev == ip6n->fb_tnl_dev) {
1342 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {
1343 err = -EFAULT;
1344 break;
1345 }
1346 ip6_tnl_parm_from_user(&p1, &p);
1347 t = ip6_tnl_locate(net, &p1, 0);
1348 } else {
1349 memset(&p, 0, sizeof(p));
1350 }
1351 if (t == NULL)
1352 t = netdev_priv(dev);
1353 ip6_tnl_parm_to_user(&p, &t->parms);
1354 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
1355 err = -EFAULT;
1356 }
1357 break;
1358 case SIOCADDTUNNEL:
1359 case SIOCCHGTUNNEL:
1360 err = -EPERM;
1361 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1362 break;
1363 err = -EFAULT;
1364 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1365 break;
1366 err = -EINVAL;
1367 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1368 p.proto != 0)
1369 break;
1370 ip6_tnl_parm_from_user(&p1, &p);
1371 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1372 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
1373 if (t != NULL) {
1374 if (t->dev != dev) {
1375 err = -EEXIST;
1376 break;
1377 }
1378 } else
1379 t = netdev_priv(dev);
1380
1381 err = ip6_tnl_update(t, &p1);
1382 }
1383 if (t) {
1384 err = 0;
1385 ip6_tnl_parm_to_user(&p, &t->parms);
1386 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1387 err = -EFAULT;
1388
1389 } else
1390 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1391 break;
1392 case SIOCDELTUNNEL:
1393 err = -EPERM;
1394 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1395 break;
1396
1397 if (dev == ip6n->fb_tnl_dev) {
1398 err = -EFAULT;
1399 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
1400 break;
1401 err = -ENOENT;
1402 ip6_tnl_parm_from_user(&p1, &p);
1403 t = ip6_tnl_locate(net, &p1, 0);
1404 if (t == NULL)
1405 break;
1406 err = -EPERM;
1407 if (t->dev == ip6n->fb_tnl_dev)
1408 break;
1409 dev = t->dev;
1410 }
1411 err = 0;
1412 unregister_netdevice(dev);
1413 break;
1414 default:
1415 err = -EINVAL;
1416 }
1417 return err;
1418 }
1419
1420 /**
1421 * ip6_tnl_change_mtu - change mtu manually for tunnel device
1422 * @dev: virtual device associated with tunnel
1423 * @new_mtu: the new mtu
1424 *
1425 * Return:
1426 * 0 on success,
1427 * %-EINVAL if mtu too small
1428 **/
1429
1430 static int
1431 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1432 {
1433 if (new_mtu < IPV6_MIN_MTU) {
1434 return -EINVAL;
1435 }
1436 dev->mtu = new_mtu;
1437 return 0;
1438 }
1439
1440
1441 static const struct net_device_ops ip6_tnl_netdev_ops = {
1442 .ndo_uninit = ip6_tnl_dev_uninit,
1443 .ndo_start_xmit = ip6_tnl_xmit,
1444 .ndo_do_ioctl = ip6_tnl_ioctl,
1445 .ndo_change_mtu = ip6_tnl_change_mtu,
1446 .ndo_get_stats = ip6_get_stats,
1447 };
1448
1449
1450 /**
1451 * ip6_tnl_dev_setup - setup virtual tunnel device
1452 * @dev: virtual device associated with tunnel
1453 *
1454 * Description:
1455 * Initialize function pointers and device parameters
1456 **/
1457
1458 static void ip6_tnl_dev_setup(struct net_device *dev)
1459 {
1460 struct ip6_tnl *t;
1461
1462 dev->netdev_ops = &ip6_tnl_netdev_ops;
1463 dev->destructor = ip6_dev_free;
1464
1465 dev->type = ARPHRD_TUNNEL6;
1466 dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
1467 dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr);
1468 t = netdev_priv(dev);
1469 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1470 dev->mtu-=8;
1471 dev->flags |= IFF_NOARP;
1472 dev->addr_len = sizeof(struct in6_addr);
1473 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1474 }
1475
1476
1477 /**
1478 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1479 * @dev: virtual device associated with tunnel
1480 **/
1481
1482 static inline int
1483 ip6_tnl_dev_init_gen(struct net_device *dev)
1484 {
1485 struct ip6_tnl *t = netdev_priv(dev);
1486
1487 t->dev = dev;
1488 t->net = dev_net(dev);
1489 dev->tstats = alloc_percpu(struct pcpu_tstats);
1490 if (!dev->tstats)
1491 return -ENOMEM;
1492 return 0;
1493 }
1494
1495 /**
1496 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1497 * @dev: virtual device associated with tunnel
1498 **/
1499
1500 static int ip6_tnl_dev_init(struct net_device *dev)
1501 {
1502 struct ip6_tnl *t = netdev_priv(dev);
1503 int err = ip6_tnl_dev_init_gen(dev);
1504
1505 if (err)
1506 return err;
1507 ip6_tnl_link_config(t);
1508 return 0;
1509 }
1510
1511 /**
1512 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1513 * @dev: fallback device
1514 *
1515 * Return: 0
1516 **/
1517
1518 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1519 {
1520 struct ip6_tnl *t = netdev_priv(dev);
1521 struct net *net = dev_net(dev);
1522 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1523 int err = ip6_tnl_dev_init_gen(dev);
1524
1525 if (err)
1526 return err;
1527
1528 t->parms.proto = IPPROTO_IPV6;
1529 dev_hold(dev);
1530
1531 ip6_tnl_link_config(t);
1532
1533 rcu_assign_pointer(ip6n->tnls_wc[0], t);
1534 return 0;
1535 }
1536
1537 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[])
1538 {
1539 u8 proto;
1540
1541 if (!data)
1542 return 0;
1543
1544 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1545 if (proto != IPPROTO_IPV6 &&
1546 proto != IPPROTO_IPIP &&
1547 proto != 0)
1548 return -EINVAL;
1549
1550 return 0;
1551 }
1552
1553 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1554 struct __ip6_tnl_parm *parms)
1555 {
1556 memset(parms, 0, sizeof(*parms));
1557
1558 if (!data)
1559 return;
1560
1561 if (data[IFLA_IPTUN_LINK])
1562 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1563
1564 if (data[IFLA_IPTUN_LOCAL])
1565 nla_memcpy(&parms->laddr, data[IFLA_IPTUN_LOCAL],
1566 sizeof(struct in6_addr));
1567
1568 if (data[IFLA_IPTUN_REMOTE])
1569 nla_memcpy(&parms->raddr, data[IFLA_IPTUN_REMOTE],
1570 sizeof(struct in6_addr));
1571
1572 if (data[IFLA_IPTUN_TTL])
1573 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1574
1575 if (data[IFLA_IPTUN_ENCAP_LIMIT])
1576 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1577
1578 if (data[IFLA_IPTUN_FLOWINFO])
1579 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1580
1581 if (data[IFLA_IPTUN_FLAGS])
1582 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1583
1584 if (data[IFLA_IPTUN_PROTO])
1585 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1586 }
1587
1588 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
1589 struct nlattr *tb[], struct nlattr *data[])
1590 {
1591 struct net *net = dev_net(dev);
1592 struct ip6_tnl *nt;
1593
1594 nt = netdev_priv(dev);
1595 ip6_tnl_netlink_parms(data, &nt->parms);
1596
1597 if (ip6_tnl_locate(net, &nt->parms, 0))
1598 return -EEXIST;
1599
1600 return ip6_tnl_create2(dev);
1601 }
1602
1603 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
1604 struct nlattr *data[])
1605 {
1606 struct ip6_tnl *t = netdev_priv(dev);
1607 struct __ip6_tnl_parm p;
1608 struct net *net = t->net;
1609 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1610
1611 if (dev == ip6n->fb_tnl_dev)
1612 return -EINVAL;
1613
1614 ip6_tnl_netlink_parms(data, &p);
1615
1616 t = ip6_tnl_locate(net, &p, 0);
1617
1618 if (t) {
1619 if (t->dev != dev)
1620 return -EEXIST;
1621 } else
1622 t = netdev_priv(dev);
1623
1624 return ip6_tnl_update(t, &p);
1625 }
1626
1627 static size_t ip6_tnl_get_size(const struct net_device *dev)
1628 {
1629 return
1630 /* IFLA_IPTUN_LINK */
1631 nla_total_size(4) +
1632 /* IFLA_IPTUN_LOCAL */
1633 nla_total_size(sizeof(struct in6_addr)) +
1634 /* IFLA_IPTUN_REMOTE */
1635 nla_total_size(sizeof(struct in6_addr)) +
1636 /* IFLA_IPTUN_TTL */
1637 nla_total_size(1) +
1638 /* IFLA_IPTUN_ENCAP_LIMIT */
1639 nla_total_size(1) +
1640 /* IFLA_IPTUN_FLOWINFO */
1641 nla_total_size(4) +
1642 /* IFLA_IPTUN_FLAGS */
1643 nla_total_size(4) +
1644 /* IFLA_IPTUN_PROTO */
1645 nla_total_size(1) +
1646 0;
1647 }
1648
1649 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
1650 {
1651 struct ip6_tnl *tunnel = netdev_priv(dev);
1652 struct __ip6_tnl_parm *parm = &tunnel->parms;
1653
1654 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
1655 nla_put(skb, IFLA_IPTUN_LOCAL, sizeof(struct in6_addr),
1656 &parm->raddr) ||
1657 nla_put(skb, IFLA_IPTUN_REMOTE, sizeof(struct in6_addr),
1658 &parm->laddr) ||
1659 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
1660 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
1661 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
1662 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
1663 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
1664 goto nla_put_failure;
1665 return 0;
1666
1667 nla_put_failure:
1668 return -EMSGSIZE;
1669 }
1670
1671 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
1672 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
1673 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) },
1674 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) },
1675 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
1676 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 },
1677 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 },
1678 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 },
1679 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
1680 };
1681
1682 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
1683 .kind = "ip6tnl",
1684 .maxtype = IFLA_IPTUN_MAX,
1685 .policy = ip6_tnl_policy,
1686 .priv_size = sizeof(struct ip6_tnl),
1687 .setup = ip6_tnl_dev_setup,
1688 .validate = ip6_tnl_validate,
1689 .newlink = ip6_tnl_newlink,
1690 .changelink = ip6_tnl_changelink,
1691 .get_size = ip6_tnl_get_size,
1692 .fill_info = ip6_tnl_fill_info,
1693 };
1694
1695 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
1696 .handler = ip4ip6_rcv,
1697 .err_handler = ip4ip6_err,
1698 .priority = 1,
1699 };
1700
1701 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
1702 .handler = ip6ip6_rcv,
1703 .err_handler = ip6ip6_err,
1704 .priority = 1,
1705 };
1706
1707 static void __net_exit ip6_tnl_destroy_tunnels(struct ip6_tnl_net *ip6n)
1708 {
1709 struct net *net = dev_net(ip6n->fb_tnl_dev);
1710 struct net_device *dev, *aux;
1711 int h;
1712 struct ip6_tnl *t;
1713 LIST_HEAD(list);
1714
1715 for_each_netdev_safe(net, dev, aux)
1716 if (dev->rtnl_link_ops == &ip6_link_ops)
1717 unregister_netdevice_queue(dev, &list);
1718
1719 for (h = 0; h < HASH_SIZE; h++) {
1720 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1721 while (t != NULL) {
1722 /* If dev is in the same netns, it has already
1723 * been added to the list by the previous loop.
1724 */
1725 if (!net_eq(dev_net(t->dev), net))
1726 unregister_netdevice_queue(t->dev, &list);
1727 t = rtnl_dereference(t->next);
1728 }
1729 }
1730
1731 t = rtnl_dereference(ip6n->tnls_wc[0]);
1732 unregister_netdevice_queue(t->dev, &list);
1733 unregister_netdevice_many(&list);
1734 }
1735
1736 static int __net_init ip6_tnl_init_net(struct net *net)
1737 {
1738 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1739 struct ip6_tnl *t = NULL;
1740 int err;
1741
1742 ip6n->tnls[0] = ip6n->tnls_wc;
1743 ip6n->tnls[1] = ip6n->tnls_r_l;
1744
1745 err = -ENOMEM;
1746 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1747 ip6_tnl_dev_setup);
1748
1749 if (!ip6n->fb_tnl_dev)
1750 goto err_alloc_dev;
1751 dev_net_set(ip6n->fb_tnl_dev, net);
1752 /* FB netdevice is special: we have one, and only one per netns.
1753 * Allowing to move it to another netns is clearly unsafe.
1754 */
1755 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
1756
1757 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1758 if (err < 0)
1759 goto err_register;
1760
1761 err = register_netdev(ip6n->fb_tnl_dev);
1762 if (err < 0)
1763 goto err_register;
1764
1765 t = netdev_priv(ip6n->fb_tnl_dev);
1766
1767 strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1768 return 0;
1769
1770 err_register:
1771 ip6_dev_free(ip6n->fb_tnl_dev);
1772 err_alloc_dev:
1773 return err;
1774 }
1775
1776 static void __net_exit ip6_tnl_exit_net(struct net *net)
1777 {
1778 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1779
1780 rtnl_lock();
1781 ip6_tnl_destroy_tunnels(ip6n);
1782 rtnl_unlock();
1783 }
1784
1785 static struct pernet_operations ip6_tnl_net_ops = {
1786 .init = ip6_tnl_init_net,
1787 .exit = ip6_tnl_exit_net,
1788 .id = &ip6_tnl_net_id,
1789 .size = sizeof(struct ip6_tnl_net),
1790 };
1791
1792 /**
1793 * ip6_tunnel_init - register protocol and reserve needed resources
1794 *
1795 * Return: 0 on success
1796 **/
1797
1798 static int __init ip6_tunnel_init(void)
1799 {
1800 int err;
1801
1802 err = register_pernet_device(&ip6_tnl_net_ops);
1803 if (err < 0)
1804 goto out_pernet;
1805
1806 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
1807 if (err < 0) {
1808 pr_err("%s: can't register ip4ip6\n", __func__);
1809 goto out_ip4ip6;
1810 }
1811
1812 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
1813 if (err < 0) {
1814 pr_err("%s: can't register ip6ip6\n", __func__);
1815 goto out_ip6ip6;
1816 }
1817 err = rtnl_link_register(&ip6_link_ops);
1818 if (err < 0)
1819 goto rtnl_link_failed;
1820
1821 return 0;
1822
1823 rtnl_link_failed:
1824 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
1825 out_ip6ip6:
1826 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
1827 out_ip4ip6:
1828 unregister_pernet_device(&ip6_tnl_net_ops);
1829 out_pernet:
1830 return err;
1831 }
1832
1833 /**
1834 * ip6_tunnel_cleanup - free resources and unregister protocol
1835 **/
1836
1837 static void __exit ip6_tunnel_cleanup(void)
1838 {
1839 rtnl_link_unregister(&ip6_link_ops);
1840 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
1841 pr_info("%s: can't deregister ip4ip6\n", __func__);
1842
1843 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
1844 pr_info("%s: can't deregister ip6ip6\n", __func__);
1845
1846 unregister_pernet_device(&ip6_tnl_net_ops);
1847 }
1848
1849 module_init(ip6_tunnel_init);
1850 module_exit(ip6_tunnel_cleanup);
Linus' kernel tree