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Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason...
[mirror_ubuntu-zesty-kernel.git] / net / ipv6 / ip6_vti.c
1 /*
2 * IPv6 virtual tunneling interface
3 *
4 * Copyright (C) 2013 secunet Security Networks AG
5 *
6 * Author:
7 * Steffen Klassert <steffen.klassert@secunet.com>
8 *
9 * Based on:
10 * net/ipv6/ip6_tunnel.c
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 */
17
18 #include <linux/module.h>
19 #include <linux/capability.h>
20 #include <linux/errno.h>
21 #include <linux/types.h>
22 #include <linux/sockios.h>
23 #include <linux/icmp.h>
24 #include <linux/if.h>
25 #include <linux/in.h>
26 #include <linux/ip.h>
27 #include <linux/net.h>
28 #include <linux/in6.h>
29 #include <linux/netdevice.h>
30 #include <linux/if_arp.h>
31 #include <linux/icmpv6.h>
32 #include <linux/init.h>
33 #include <linux/route.h>
34 #include <linux/rtnetlink.h>
35 #include <linux/netfilter_ipv6.h>
36 #include <linux/slab.h>
37 #include <linux/hash.h>
38
39 #include <linux/uaccess.h>
40 #include <linux/atomic.h>
41
42 #include <net/icmp.h>
43 #include <net/ip.h>
44 #include <net/ip_tunnels.h>
45 #include <net/ipv6.h>
46 #include <net/ip6_route.h>
47 #include <net/addrconf.h>
48 #include <net/ip6_tunnel.h>
49 #include <net/xfrm.h>
50 #include <net/net_namespace.h>
51 #include <net/netns/generic.h>
52
53 #define HASH_SIZE_SHIFT 5
54 #define HASH_SIZE (1 << HASH_SIZE_SHIFT)
55
56 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
57 {
58 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
59
60 return hash_32(hash, HASH_SIZE_SHIFT);
61 }
62
63 static int vti6_dev_init(struct net_device *dev);
64 static void vti6_dev_setup(struct net_device *dev);
65 static struct rtnl_link_ops vti6_link_ops __read_mostly;
66
67 static int vti6_net_id __read_mostly;
68 struct vti6_net {
69 /* the vti6 tunnel fallback device */
70 struct net_device *fb_tnl_dev;
71 /* lists for storing tunnels in use */
72 struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
73 struct ip6_tnl __rcu *tnls_wc[1];
74 struct ip6_tnl __rcu **tnls[2];
75 };
76
77 #define for_each_vti6_tunnel_rcu(start) \
78 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
79
80 /**
81 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses
82 * @net: network namespace
83 * @remote: the address of the tunnel exit-point
84 * @local: the address of the tunnel entry-point
85 *
86 * Return:
87 * tunnel matching given end-points if found,
88 * else fallback tunnel if its device is up,
89 * else %NULL
90 **/
91 static struct ip6_tnl *
92 vti6_tnl_lookup(struct net *net, const struct in6_addr *remote,
93 const struct in6_addr *local)
94 {
95 unsigned int hash = HASH(remote, local);
96 struct ip6_tnl *t;
97 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
98 struct in6_addr any;
99
100 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
101 if (ipv6_addr_equal(local, &t->parms.laddr) &&
102 ipv6_addr_equal(remote, &t->parms.raddr) &&
103 (t->dev->flags & IFF_UP))
104 return t;
105 }
106
107 memset(&any, 0, sizeof(any));
108 hash = HASH(&any, local);
109 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
110 if (ipv6_addr_equal(local, &t->parms.laddr) &&
111 (t->dev->flags & IFF_UP))
112 return t;
113 }
114
115 hash = HASH(remote, &any);
116 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
117 if (ipv6_addr_equal(remote, &t->parms.raddr) &&
118 (t->dev->flags & IFF_UP))
119 return t;
120 }
121
122 t = rcu_dereference(ip6n->tnls_wc[0]);
123 if (t && (t->dev->flags & IFF_UP))
124 return t;
125
126 return NULL;
127 }
128
129 /**
130 * vti6_tnl_bucket - get head of list matching given tunnel parameters
131 * @p: parameters containing tunnel end-points
132 *
133 * Description:
134 * vti6_tnl_bucket() returns the head of the list matching the
135 * &struct in6_addr entries laddr and raddr in @p.
136 *
137 * Return: head of IPv6 tunnel list
138 **/
139 static struct ip6_tnl __rcu **
140 vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
141 {
142 const struct in6_addr *remote = &p->raddr;
143 const struct in6_addr *local = &p->laddr;
144 unsigned int h = 0;
145 int prio = 0;
146
147 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
148 prio = 1;
149 h = HASH(remote, local);
150 }
151 return &ip6n->tnls[prio][h];
152 }
153
154 static void
155 vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
156 {
157 struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
158
159 rcu_assign_pointer(t->next , rtnl_dereference(*tp));
160 rcu_assign_pointer(*tp, t);
161 }
162
163 static void
164 vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
165 {
166 struct ip6_tnl __rcu **tp;
167 struct ip6_tnl *iter;
168
169 for (tp = vti6_tnl_bucket(ip6n, &t->parms);
170 (iter = rtnl_dereference(*tp)) != NULL;
171 tp = &iter->next) {
172 if (t == iter) {
173 rcu_assign_pointer(*tp, t->next);
174 break;
175 }
176 }
177 }
178
179 static void vti6_dev_free(struct net_device *dev)
180 {
181 free_percpu(dev->tstats);
182 free_netdev(dev);
183 }
184
185 static int vti6_tnl_create2(struct net_device *dev)
186 {
187 struct ip6_tnl *t = netdev_priv(dev);
188 struct net *net = dev_net(dev);
189 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
190 int err;
191
192 err = register_netdevice(dev);
193 if (err < 0)
194 goto out;
195
196 strcpy(t->parms.name, dev->name);
197 dev->rtnl_link_ops = &vti6_link_ops;
198
199 dev_hold(dev);
200 vti6_tnl_link(ip6n, t);
201
202 return 0;
203
204 out:
205 return err;
206 }
207
208 static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
209 {
210 struct net_device *dev;
211 struct ip6_tnl *t;
212 char name[IFNAMSIZ];
213 int err;
214
215 if (p->name[0])
216 strlcpy(name, p->name, IFNAMSIZ);
217 else
218 sprintf(name, "ip6_vti%%d");
219
220 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
221 if (!dev)
222 goto failed;
223
224 dev_net_set(dev, net);
225
226 t = netdev_priv(dev);
227 t->parms = *p;
228 t->net = dev_net(dev);
229
230 err = vti6_tnl_create2(dev);
231 if (err < 0)
232 goto failed_free;
233
234 return t;
235
236 failed_free:
237 vti6_dev_free(dev);
238 failed:
239 return NULL;
240 }
241
242 /**
243 * vti6_locate - find or create tunnel matching given parameters
244 * @net: network namespace
245 * @p: tunnel parameters
246 * @create: != 0 if allowed to create new tunnel if no match found
247 *
248 * Description:
249 * vti6_locate() first tries to locate an existing tunnel
250 * based on @parms. If this is unsuccessful, but @create is set a new
251 * tunnel device is created and registered for use.
252 *
253 * Return:
254 * matching tunnel or NULL
255 **/
256 static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
257 int create)
258 {
259 const struct in6_addr *remote = &p->raddr;
260 const struct in6_addr *local = &p->laddr;
261 struct ip6_tnl __rcu **tp;
262 struct ip6_tnl *t;
263 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
264
265 for (tp = vti6_tnl_bucket(ip6n, p);
266 (t = rtnl_dereference(*tp)) != NULL;
267 tp = &t->next) {
268 if (ipv6_addr_equal(local, &t->parms.laddr) &&
269 ipv6_addr_equal(remote, &t->parms.raddr)) {
270 if (create)
271 return NULL;
272
273 return t;
274 }
275 }
276 if (!create)
277 return NULL;
278 return vti6_tnl_create(net, p);
279 }
280
281 /**
282 * vti6_dev_uninit - tunnel device uninitializer
283 * @dev: the device to be destroyed
284 *
285 * Description:
286 * vti6_dev_uninit() removes tunnel from its list
287 **/
288 static void vti6_dev_uninit(struct net_device *dev)
289 {
290 struct ip6_tnl *t = netdev_priv(dev);
291 struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
292
293 if (dev == ip6n->fb_tnl_dev)
294 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
295 else
296 vti6_tnl_unlink(ip6n, t);
297 dev_put(dev);
298 }
299
300 static int vti6_rcv(struct sk_buff *skb)
301 {
302 struct ip6_tnl *t;
303 const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
304
305 rcu_read_lock();
306 t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
307 if (t) {
308 if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
309 rcu_read_unlock();
310 goto discard;
311 }
312
313 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
314 rcu_read_unlock();
315 return 0;
316 }
317
318 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
319 t->dev->stats.rx_dropped++;
320 rcu_read_unlock();
321 goto discard;
322 }
323
324 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
325
326 rcu_read_unlock();
327
328 return xfrm6_rcv(skb);
329 }
330 rcu_read_unlock();
331 return -EINVAL;
332 discard:
333 kfree_skb(skb);
334 return 0;
335 }
336
337 static int vti6_rcv_cb(struct sk_buff *skb, int err)
338 {
339 unsigned short family;
340 struct net_device *dev;
341 struct pcpu_sw_netstats *tstats;
342 struct xfrm_state *x;
343 struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
344 u32 orig_mark = skb->mark;
345 int ret;
346
347 if (!t)
348 return 1;
349
350 dev = t->dev;
351
352 if (err) {
353 dev->stats.rx_errors++;
354 dev->stats.rx_dropped++;
355
356 return 0;
357 }
358
359 x = xfrm_input_state(skb);
360 family = x->inner_mode->afinfo->family;
361
362 skb->mark = be32_to_cpu(t->parms.i_key);
363 ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
364 skb->mark = orig_mark;
365
366 if (!ret)
367 return -EPERM;
368
369 skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
370 skb->dev = dev;
371
372 tstats = this_cpu_ptr(dev->tstats);
373 u64_stats_update_begin(&tstats->syncp);
374 tstats->rx_packets++;
375 tstats->rx_bytes += skb->len;
376 u64_stats_update_end(&tstats->syncp);
377
378 return 0;
379 }
380
381 /**
382 * vti6_addr_conflict - compare packet addresses to tunnel's own
383 * @t: the outgoing tunnel device
384 * @hdr: IPv6 header from the incoming packet
385 *
386 * Description:
387 * Avoid trivial tunneling loop by checking that tunnel exit-point
388 * doesn't match source of incoming packet.
389 *
390 * Return:
391 * 1 if conflict,
392 * 0 else
393 **/
394 static inline bool
395 vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
396 {
397 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
398 }
399
400 static bool vti6_state_check(const struct xfrm_state *x,
401 const struct in6_addr *dst,
402 const struct in6_addr *src)
403 {
404 xfrm_address_t *daddr = (xfrm_address_t *)dst;
405 xfrm_address_t *saddr = (xfrm_address_t *)src;
406
407 /* if there is no transform then this tunnel is not functional.
408 * Or if the xfrm is not mode tunnel.
409 */
410 if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
411 x->props.family != AF_INET6)
412 return false;
413
414 if (ipv6_addr_any(dst))
415 return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
416
417 if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
418 return false;
419
420 return true;
421 }
422
423 /**
424 * vti6_xmit - send a packet
425 * @skb: the outgoing socket buffer
426 * @dev: the outgoing tunnel device
427 * @fl: the flow informations for the xfrm_lookup
428 **/
429 static int
430 vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
431 {
432 struct ip6_tnl *t = netdev_priv(dev);
433 struct net_device_stats *stats = &t->dev->stats;
434 struct dst_entry *dst = skb_dst(skb);
435 struct net_device *tdev;
436 struct xfrm_state *x;
437 int err = -1;
438 int mtu;
439
440 if (!dst)
441 goto tx_err_link_failure;
442
443 dst_hold(dst);
444 dst = xfrm_lookup(t->net, dst, fl, NULL, 0);
445 if (IS_ERR(dst)) {
446 err = PTR_ERR(dst);
447 dst = NULL;
448 goto tx_err_link_failure;
449 }
450
451 x = dst->xfrm;
452 if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr))
453 goto tx_err_link_failure;
454
455 if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr,
456 (const struct in6_addr *)&x->id.daddr))
457 goto tx_err_link_failure;
458
459 tdev = dst->dev;
460
461 if (tdev == dev) {
462 stats->collisions++;
463 net_warn_ratelimited("%s: Local routing loop detected!\n",
464 t->parms.name);
465 goto tx_err_dst_release;
466 }
467
468 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
469 skb_dst_set(skb, dst);
470 skb->dev = skb_dst(skb)->dev;
471
472 mtu = dst_mtu(dst);
473 if (!skb->ignore_df && skb->len > mtu) {
474 skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu);
475
476 if (skb->protocol == htons(ETH_P_IPV6))
477 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
478 else
479 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
480 htonl(mtu));
481
482 return -EMSGSIZE;
483 }
484
485 err = dst_output(skb);
486 if (net_xmit_eval(err) == 0) {
487 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
488
489 u64_stats_update_begin(&tstats->syncp);
490 tstats->tx_bytes += skb->len;
491 tstats->tx_packets++;
492 u64_stats_update_end(&tstats->syncp);
493 } else {
494 stats->tx_errors++;
495 stats->tx_aborted_errors++;
496 }
497
498 return 0;
499 tx_err_link_failure:
500 stats->tx_carrier_errors++;
501 dst_link_failure(skb);
502 tx_err_dst_release:
503 dst_release(dst);
504 return err;
505 }
506
507 static netdev_tx_t
508 vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
509 {
510 struct ip6_tnl *t = netdev_priv(dev);
511 struct net_device_stats *stats = &t->dev->stats;
512 struct ipv6hdr *ipv6h;
513 struct flowi fl;
514 int ret;
515
516 memset(&fl, 0, sizeof(fl));
517
518 switch (skb->protocol) {
519 case htons(ETH_P_IPV6):
520 ipv6h = ipv6_hdr(skb);
521
522 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
523 vti6_addr_conflict(t, ipv6h))
524 goto tx_err;
525
526 xfrm_decode_session(skb, &fl, AF_INET6);
527 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
528 break;
529 case htons(ETH_P_IP):
530 xfrm_decode_session(skb, &fl, AF_INET);
531 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
532 break;
533 default:
534 goto tx_err;
535 }
536
537 /* override mark with tunnel output key */
538 fl.flowi_mark = be32_to_cpu(t->parms.o_key);
539
540 ret = vti6_xmit(skb, dev, &fl);
541 if (ret < 0)
542 goto tx_err;
543
544 return NETDEV_TX_OK;
545
546 tx_err:
547 stats->tx_errors++;
548 stats->tx_dropped++;
549 kfree_skb(skb);
550 return NETDEV_TX_OK;
551 }
552
553 static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
554 u8 type, u8 code, int offset, __be32 info)
555 {
556 __be32 spi;
557 __u32 mark;
558 struct xfrm_state *x;
559 struct ip6_tnl *t;
560 struct ip_esp_hdr *esph;
561 struct ip_auth_hdr *ah;
562 struct ip_comp_hdr *ipch;
563 struct net *net = dev_net(skb->dev);
564 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
565 int protocol = iph->nexthdr;
566
567 t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
568 if (!t)
569 return -1;
570
571 mark = be32_to_cpu(t->parms.o_key);
572
573 switch (protocol) {
574 case IPPROTO_ESP:
575 esph = (struct ip_esp_hdr *)(skb->data + offset);
576 spi = esph->spi;
577 break;
578 case IPPROTO_AH:
579 ah = (struct ip_auth_hdr *)(skb->data + offset);
580 spi = ah->spi;
581 break;
582 case IPPROTO_COMP:
583 ipch = (struct ip_comp_hdr *)(skb->data + offset);
584 spi = htonl(ntohs(ipch->cpi));
585 break;
586 default:
587 return 0;
588 }
589
590 if (type != ICMPV6_PKT_TOOBIG &&
591 type != NDISC_REDIRECT)
592 return 0;
593
594 x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
595 spi, protocol, AF_INET6);
596 if (!x)
597 return 0;
598
599 if (type == NDISC_REDIRECT)
600 ip6_redirect(skb, net, skb->dev->ifindex, 0);
601 else
602 ip6_update_pmtu(skb, net, info, 0, 0);
603 xfrm_state_put(x);
604
605 return 0;
606 }
607
608 static void vti6_link_config(struct ip6_tnl *t)
609 {
610 struct net_device *dev = t->dev;
611 struct __ip6_tnl_parm *p = &t->parms;
612
613 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
614 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
615
616 p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
617 IP6_TNL_F_CAP_PER_PACKET);
618 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
619
620 if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
621 dev->flags |= IFF_POINTOPOINT;
622 else
623 dev->flags &= ~IFF_POINTOPOINT;
624 }
625
626 /**
627 * vti6_tnl_change - update the tunnel parameters
628 * @t: tunnel to be changed
629 * @p: tunnel configuration parameters
630 *
631 * Description:
632 * vti6_tnl_change() updates the tunnel parameters
633 **/
634 static int
635 vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
636 {
637 t->parms.laddr = p->laddr;
638 t->parms.raddr = p->raddr;
639 t->parms.link = p->link;
640 t->parms.i_key = p->i_key;
641 t->parms.o_key = p->o_key;
642 t->parms.proto = p->proto;
643 ip6_tnl_dst_reset(t);
644 vti6_link_config(t);
645 return 0;
646 }
647
648 static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
649 {
650 struct net *net = dev_net(t->dev);
651 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
652 int err;
653
654 vti6_tnl_unlink(ip6n, t);
655 synchronize_net();
656 err = vti6_tnl_change(t, p);
657 vti6_tnl_link(ip6n, t);
658 netdev_state_change(t->dev);
659 return err;
660 }
661
662 static void
663 vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
664 {
665 p->laddr = u->laddr;
666 p->raddr = u->raddr;
667 p->link = u->link;
668 p->i_key = u->i_key;
669 p->o_key = u->o_key;
670 p->proto = u->proto;
671
672 memcpy(p->name, u->name, sizeof(u->name));
673 }
674
675 static void
676 vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
677 {
678 u->laddr = p->laddr;
679 u->raddr = p->raddr;
680 u->link = p->link;
681 u->i_key = p->i_key;
682 u->o_key = p->o_key;
683 u->proto = p->proto;
684
685 memcpy(u->name, p->name, sizeof(u->name));
686 }
687
688 /**
689 * vti6_tnl_ioctl - configure vti6 tunnels from userspace
690 * @dev: virtual device associated with tunnel
691 * @ifr: parameters passed from userspace
692 * @cmd: command to be performed
693 *
694 * Description:
695 * vti6_ioctl() is used for managing vti6 tunnels
696 * from userspace.
697 *
698 * The possible commands are the following:
699 * %SIOCGETTUNNEL: get tunnel parameters for device
700 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
701 * %SIOCCHGTUNNEL: change tunnel parameters to those given
702 * %SIOCDELTUNNEL: delete tunnel
703 *
704 * The fallback device "ip6_vti0", created during module
705 * initialization, can be used for creating other tunnel devices.
706 *
707 * Return:
708 * 0 on success,
709 * %-EFAULT if unable to copy data to or from userspace,
710 * %-EPERM if current process hasn't %CAP_NET_ADMIN set
711 * %-EINVAL if passed tunnel parameters are invalid,
712 * %-EEXIST if changing a tunnel's parameters would cause a conflict
713 * %-ENODEV if attempting to change or delete a nonexisting device
714 **/
715 static int
716 vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
717 {
718 int err = 0;
719 struct ip6_tnl_parm2 p;
720 struct __ip6_tnl_parm p1;
721 struct ip6_tnl *t = NULL;
722 struct net *net = dev_net(dev);
723 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
724
725 switch (cmd) {
726 case SIOCGETTUNNEL:
727 if (dev == ip6n->fb_tnl_dev) {
728 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
729 err = -EFAULT;
730 break;
731 }
732 vti6_parm_from_user(&p1, &p);
733 t = vti6_locate(net, &p1, 0);
734 } else {
735 memset(&p, 0, sizeof(p));
736 }
737 if (!t)
738 t = netdev_priv(dev);
739 vti6_parm_to_user(&p, &t->parms);
740 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
741 err = -EFAULT;
742 break;
743 case SIOCADDTUNNEL:
744 case SIOCCHGTUNNEL:
745 err = -EPERM;
746 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
747 break;
748 err = -EFAULT;
749 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
750 break;
751 err = -EINVAL;
752 if (p.proto != IPPROTO_IPV6 && p.proto != 0)
753 break;
754 vti6_parm_from_user(&p1, &p);
755 t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
756 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
757 if (t) {
758 if (t->dev != dev) {
759 err = -EEXIST;
760 break;
761 }
762 } else
763 t = netdev_priv(dev);
764
765 err = vti6_update(t, &p1);
766 }
767 if (t) {
768 err = 0;
769 vti6_parm_to_user(&p, &t->parms);
770 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
771 err = -EFAULT;
772
773 } else
774 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
775 break;
776 case SIOCDELTUNNEL:
777 err = -EPERM;
778 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
779 break;
780
781 if (dev == ip6n->fb_tnl_dev) {
782 err = -EFAULT;
783 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
784 break;
785 err = -ENOENT;
786 vti6_parm_from_user(&p1, &p);
787 t = vti6_locate(net, &p1, 0);
788 if (!t)
789 break;
790 err = -EPERM;
791 if (t->dev == ip6n->fb_tnl_dev)
792 break;
793 dev = t->dev;
794 }
795 err = 0;
796 unregister_netdevice(dev);
797 break;
798 default:
799 err = -EINVAL;
800 }
801 return err;
802 }
803
804 /**
805 * vti6_tnl_change_mtu - change mtu manually for tunnel device
806 * @dev: virtual device associated with tunnel
807 * @new_mtu: the new mtu
808 *
809 * Return:
810 * 0 on success,
811 * %-EINVAL if mtu too small
812 **/
813 static int vti6_change_mtu(struct net_device *dev, int new_mtu)
814 {
815 if (new_mtu < IPV6_MIN_MTU)
816 return -EINVAL;
817
818 dev->mtu = new_mtu;
819 return 0;
820 }
821
822 static const struct net_device_ops vti6_netdev_ops = {
823 .ndo_init = vti6_dev_init,
824 .ndo_uninit = vti6_dev_uninit,
825 .ndo_start_xmit = vti6_tnl_xmit,
826 .ndo_do_ioctl = vti6_ioctl,
827 .ndo_change_mtu = vti6_change_mtu,
828 .ndo_get_stats64 = ip_tunnel_get_stats64,
829 .ndo_get_iflink = ip6_tnl_get_iflink,
830 };
831
832 /**
833 * vti6_dev_setup - setup virtual tunnel device
834 * @dev: virtual device associated with tunnel
835 *
836 * Description:
837 * Initialize function pointers and device parameters
838 **/
839 static void vti6_dev_setup(struct net_device *dev)
840 {
841 dev->netdev_ops = &vti6_netdev_ops;
842 dev->destructor = vti6_dev_free;
843
844 dev->type = ARPHRD_TUNNEL6;
845 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
846 dev->mtu = ETH_DATA_LEN;
847 dev->flags |= IFF_NOARP;
848 dev->addr_len = sizeof(struct in6_addr);
849 netif_keep_dst(dev);
850 }
851
852 /**
853 * vti6_dev_init_gen - general initializer for all tunnel devices
854 * @dev: virtual device associated with tunnel
855 **/
856 static inline int vti6_dev_init_gen(struct net_device *dev)
857 {
858 struct ip6_tnl *t = netdev_priv(dev);
859
860 t->dev = dev;
861 t->net = dev_net(dev);
862 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
863 if (!dev->tstats)
864 return -ENOMEM;
865 return 0;
866 }
867
868 /**
869 * vti6_dev_init - initializer for all non fallback tunnel devices
870 * @dev: virtual device associated with tunnel
871 **/
872 static int vti6_dev_init(struct net_device *dev)
873 {
874 struct ip6_tnl *t = netdev_priv(dev);
875 int err = vti6_dev_init_gen(dev);
876
877 if (err)
878 return err;
879 vti6_link_config(t);
880 return 0;
881 }
882
883 /**
884 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device
885 * @dev: fallback device
886 *
887 * Return: 0
888 **/
889 static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
890 {
891 struct ip6_tnl *t = netdev_priv(dev);
892 struct net *net = dev_net(dev);
893 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
894
895 t->parms.proto = IPPROTO_IPV6;
896 dev_hold(dev);
897
898 rcu_assign_pointer(ip6n->tnls_wc[0], t);
899 return 0;
900 }
901
902 static int vti6_validate(struct nlattr *tb[], struct nlattr *data[])
903 {
904 return 0;
905 }
906
907 static void vti6_netlink_parms(struct nlattr *data[],
908 struct __ip6_tnl_parm *parms)
909 {
910 memset(parms, 0, sizeof(*parms));
911
912 if (!data)
913 return;
914
915 if (data[IFLA_VTI_LINK])
916 parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
917
918 if (data[IFLA_VTI_LOCAL])
919 parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]);
920
921 if (data[IFLA_VTI_REMOTE])
922 parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]);
923
924 if (data[IFLA_VTI_IKEY])
925 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
926
927 if (data[IFLA_VTI_OKEY])
928 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
929 }
930
931 static int vti6_newlink(struct net *src_net, struct net_device *dev,
932 struct nlattr *tb[], struct nlattr *data[])
933 {
934 struct net *net = dev_net(dev);
935 struct ip6_tnl *nt;
936
937 nt = netdev_priv(dev);
938 vti6_netlink_parms(data, &nt->parms);
939
940 nt->parms.proto = IPPROTO_IPV6;
941
942 if (vti6_locate(net, &nt->parms, 0))
943 return -EEXIST;
944
945 return vti6_tnl_create2(dev);
946 }
947
948 static void vti6_dellink(struct net_device *dev, struct list_head *head)
949 {
950 struct net *net = dev_net(dev);
951 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
952
953 if (dev != ip6n->fb_tnl_dev)
954 unregister_netdevice_queue(dev, head);
955 }
956
957 static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
958 struct nlattr *data[])
959 {
960 struct ip6_tnl *t;
961 struct __ip6_tnl_parm p;
962 struct net *net = dev_net(dev);
963 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
964
965 if (dev == ip6n->fb_tnl_dev)
966 return -EINVAL;
967
968 vti6_netlink_parms(data, &p);
969
970 t = vti6_locate(net, &p, 0);
971
972 if (t) {
973 if (t->dev != dev)
974 return -EEXIST;
975 } else
976 t = netdev_priv(dev);
977
978 return vti6_update(t, &p);
979 }
980
981 static size_t vti6_get_size(const struct net_device *dev)
982 {
983 return
984 /* IFLA_VTI_LINK */
985 nla_total_size(4) +
986 /* IFLA_VTI_LOCAL */
987 nla_total_size(sizeof(struct in6_addr)) +
988 /* IFLA_VTI_REMOTE */
989 nla_total_size(sizeof(struct in6_addr)) +
990 /* IFLA_VTI_IKEY */
991 nla_total_size(4) +
992 /* IFLA_VTI_OKEY */
993 nla_total_size(4) +
994 0;
995 }
996
997 static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
998 {
999 struct ip6_tnl *tunnel = netdev_priv(dev);
1000 struct __ip6_tnl_parm *parm = &tunnel->parms;
1001
1002 if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
1003 nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) ||
1004 nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) ||
1005 nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
1006 nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key))
1007 goto nla_put_failure;
1008 return 0;
1009
1010 nla_put_failure:
1011 return -EMSGSIZE;
1012 }
1013
1014 static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
1015 [IFLA_VTI_LINK] = { .type = NLA_U32 },
1016 [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) },
1017 [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) },
1018 [IFLA_VTI_IKEY] = { .type = NLA_U32 },
1019 [IFLA_VTI_OKEY] = { .type = NLA_U32 },
1020 };
1021
1022 static struct rtnl_link_ops vti6_link_ops __read_mostly = {
1023 .kind = "vti6",
1024 .maxtype = IFLA_VTI_MAX,
1025 .policy = vti6_policy,
1026 .priv_size = sizeof(struct ip6_tnl),
1027 .setup = vti6_dev_setup,
1028 .validate = vti6_validate,
1029 .newlink = vti6_newlink,
1030 .dellink = vti6_dellink,
1031 .changelink = vti6_changelink,
1032 .get_size = vti6_get_size,
1033 .fill_info = vti6_fill_info,
1034 .get_link_net = ip6_tnl_get_link_net,
1035 };
1036
1037 static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n)
1038 {
1039 int h;
1040 struct ip6_tnl *t;
1041 LIST_HEAD(list);
1042
1043 for (h = 0; h < HASH_SIZE; h++) {
1044 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1045 while (t) {
1046 unregister_netdevice_queue(t->dev, &list);
1047 t = rtnl_dereference(t->next);
1048 }
1049 }
1050
1051 t = rtnl_dereference(ip6n->tnls_wc[0]);
1052 unregister_netdevice_queue(t->dev, &list);
1053 unregister_netdevice_many(&list);
1054 }
1055
1056 static int __net_init vti6_init_net(struct net *net)
1057 {
1058 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1059 struct ip6_tnl *t = NULL;
1060 int err;
1061
1062 ip6n->tnls[0] = ip6n->tnls_wc;
1063 ip6n->tnls[1] = ip6n->tnls_r_l;
1064
1065 err = -ENOMEM;
1066 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
1067 NET_NAME_UNKNOWN, vti6_dev_setup);
1068
1069 if (!ip6n->fb_tnl_dev)
1070 goto err_alloc_dev;
1071 dev_net_set(ip6n->fb_tnl_dev, net);
1072 ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops;
1073
1074 err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1075 if (err < 0)
1076 goto err_register;
1077
1078 err = register_netdev(ip6n->fb_tnl_dev);
1079 if (err < 0)
1080 goto err_register;
1081
1082 t = netdev_priv(ip6n->fb_tnl_dev);
1083
1084 strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1085 return 0;
1086
1087 err_register:
1088 vti6_dev_free(ip6n->fb_tnl_dev);
1089 err_alloc_dev:
1090 return err;
1091 }
1092
1093 static void __net_exit vti6_exit_net(struct net *net)
1094 {
1095 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1096
1097 rtnl_lock();
1098 vti6_destroy_tunnels(ip6n);
1099 rtnl_unlock();
1100 }
1101
1102 static struct pernet_operations vti6_net_ops = {
1103 .init = vti6_init_net,
1104 .exit = vti6_exit_net,
1105 .id = &vti6_net_id,
1106 .size = sizeof(struct vti6_net),
1107 };
1108
1109 static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
1110 .handler = vti6_rcv,
1111 .cb_handler = vti6_rcv_cb,
1112 .err_handler = vti6_err,
1113 .priority = 100,
1114 };
1115
1116 static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
1117 .handler = vti6_rcv,
1118 .cb_handler = vti6_rcv_cb,
1119 .err_handler = vti6_err,
1120 .priority = 100,
1121 };
1122
1123 static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
1124 .handler = vti6_rcv,
1125 .cb_handler = vti6_rcv_cb,
1126 .err_handler = vti6_err,
1127 .priority = 100,
1128 };
1129
1130 /**
1131 * vti6_tunnel_init - register protocol and reserve needed resources
1132 *
1133 * Return: 0 on success
1134 **/
1135 static int __init vti6_tunnel_init(void)
1136 {
1137 const char *msg;
1138 int err;
1139
1140 msg = "tunnel device";
1141 err = register_pernet_device(&vti6_net_ops);
1142 if (err < 0)
1143 goto pernet_dev_failed;
1144
1145 msg = "tunnel protocols";
1146 err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
1147 if (err < 0)
1148 goto xfrm_proto_esp_failed;
1149 err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
1150 if (err < 0)
1151 goto xfrm_proto_ah_failed;
1152 err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
1153 if (err < 0)
1154 goto xfrm_proto_comp_failed;
1155
1156 msg = "netlink interface";
1157 err = rtnl_link_register(&vti6_link_ops);
1158 if (err < 0)
1159 goto rtnl_link_failed;
1160
1161 return 0;
1162
1163 rtnl_link_failed:
1164 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1165 xfrm_proto_comp_failed:
1166 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1167 xfrm_proto_ah_failed:
1168 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1169 xfrm_proto_esp_failed:
1170 unregister_pernet_device(&vti6_net_ops);
1171 pernet_dev_failed:
1172 pr_err("vti6 init: failed to register %s\n", msg);
1173 return err;
1174 }
1175
1176 /**
1177 * vti6_tunnel_cleanup - free resources and unregister protocol
1178 **/
1179 static void __exit vti6_tunnel_cleanup(void)
1180 {
1181 rtnl_link_unregister(&vti6_link_ops);
1182 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1183 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1184 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1185 unregister_pernet_device(&vti6_net_ops);
1186 }
1187
1188 module_init(vti6_tunnel_init);
1189 module_exit(vti6_tunnel_cleanup);
1190 MODULE_LICENSE("GPL");
1191 MODULE_ALIAS_RTNL_LINK("vti6");
1192 MODULE_ALIAS_NETDEV("ip6_vti0");
1193 MODULE_AUTHOR("Steffen Klassert");
1194 MODULE_DESCRIPTION("IPv6 virtual tunnel interface");