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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#include <linux/etherdevice.h>
53
54#define IP6_VTI_HASH_SIZE_SHIFT 5
55#define IP6_VTI_HASH_SIZE (1 << IP6_VTI_HASH_SIZE_SHIFT)
56
57static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
58{
59 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
60
61 return hash_32(hash, IP6_VTI_HASH_SIZE_SHIFT);
62}
63
64static int vti6_dev_init(struct net_device *dev);
65static void vti6_dev_setup(struct net_device *dev);
66static struct rtnl_link_ops vti6_link_ops __read_mostly;
67
68static unsigned int vti6_net_id __read_mostly;
69struct vti6_net {
70 /* the vti6 tunnel fallback device */
71 struct net_device *fb_tnl_dev;
72 /* lists for storing tunnels in use */
73 struct ip6_tnl __rcu *tnls_r_l[IP6_VTI_HASH_SIZE];
74 struct ip6_tnl __rcu *tnls_wc[1];
75 struct ip6_tnl __rcu **tnls[2];
76};
77
78#define for_each_vti6_tunnel_rcu(start) \
79 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
80
81/**
82 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses
83 * @net: network namespace
84 * @remote: the address of the tunnel exit-point
85 * @local: the address of the tunnel entry-point
86 *
87 * Return:
88 * tunnel matching given end-points if found,
89 * else fallback tunnel if its device is up,
90 * else %NULL
91 **/
92static struct ip6_tnl *
93vti6_tnl_lookup(struct net *net, const struct in6_addr *remote,
94 const struct in6_addr *local)
95{
96 unsigned int hash = HASH(remote, local);
97 struct ip6_tnl *t;
98 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
99 struct in6_addr any;
100
101 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
102 if (ipv6_addr_equal(local, &t->parms.laddr) &&
103 ipv6_addr_equal(remote, &t->parms.raddr) &&
104 (t->dev->flags & IFF_UP))
105 return t;
106 }
107
108 memset(&any, 0, sizeof(any));
109 hash = HASH(&any, local);
110 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
111 if (ipv6_addr_equal(local, &t->parms.laddr) &&
112 (t->dev->flags & IFF_UP))
113 return t;
114 }
115
116 hash = HASH(remote, &any);
117 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
118 if (ipv6_addr_equal(remote, &t->parms.raddr) &&
119 (t->dev->flags & IFF_UP))
120 return t;
121 }
122
123 t = rcu_dereference(ip6n->tnls_wc[0]);
124 if (t && (t->dev->flags & IFF_UP))
125 return t;
126
127 return NULL;
128}
129
130/**
131 * vti6_tnl_bucket - get head of list matching given tunnel parameters
132 * @p: parameters containing tunnel end-points
133 *
134 * Description:
135 * vti6_tnl_bucket() returns the head of the list matching the
136 * &struct in6_addr entries laddr and raddr in @p.
137 *
138 * Return: head of IPv6 tunnel list
139 **/
140static struct ip6_tnl __rcu **
141vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
142{
143 const struct in6_addr *remote = &p->raddr;
144 const struct in6_addr *local = &p->laddr;
145 unsigned int h = 0;
146 int prio = 0;
147
148 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
149 prio = 1;
150 h = HASH(remote, local);
151 }
152 return &ip6n->tnls[prio][h];
153}
154
155static void
156vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
157{
158 struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
159
160 rcu_assign_pointer(t->next , rtnl_dereference(*tp));
161 rcu_assign_pointer(*tp, t);
162}
163
164static void
165vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
166{
167 struct ip6_tnl __rcu **tp;
168 struct ip6_tnl *iter;
169
170 for (tp = vti6_tnl_bucket(ip6n, &t->parms);
171 (iter = rtnl_dereference(*tp)) != NULL;
172 tp = &iter->next) {
173 if (t == iter) {
174 rcu_assign_pointer(*tp, t->next);
175 break;
176 }
177 }
178}
179
180static void vti6_dev_free(struct net_device *dev)
181{
182 free_percpu(dev->tstats);
183}
184
185static 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 dev->rtnl_link_ops = &vti6_link_ops;
193 err = register_netdevice(dev);
194 if (err < 0)
195 goto out;
196
197 strcpy(t->parms.name, dev->name);
198
199 dev_hold(dev);
200 vti6_tnl_link(ip6n, t);
201
202 return 0;
203
204out:
205 return err;
206}
207
208static 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 if (!dev_valid_name(p->name))
217 goto failed;
218 strlcpy(name, p->name, IFNAMSIZ);
219 } else {
220 sprintf(name, "ip6_vti%%d");
221 }
222
223 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
224 if (!dev)
225 goto failed;
226
227 dev_net_set(dev, net);
228
229 t = netdev_priv(dev);
230 t->parms = *p;
231 t->net = dev_net(dev);
232
233 err = vti6_tnl_create2(dev);
234 if (err < 0)
235 goto failed_free;
236
237 return t;
238
239failed_free:
240 free_netdev(dev);
241failed:
242 return NULL;
243}
244
245/**
246 * vti6_locate - find or create tunnel matching given parameters
247 * @net: network namespace
248 * @p: tunnel parameters
249 * @create: != 0 if allowed to create new tunnel if no match found
250 *
251 * Description:
252 * vti6_locate() first tries to locate an existing tunnel
253 * based on @parms. If this is unsuccessful, but @create is set a new
254 * tunnel device is created and registered for use.
255 *
256 * Return:
257 * matching tunnel or NULL
258 **/
259static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
260 int create)
261{
262 const struct in6_addr *remote = &p->raddr;
263 const struct in6_addr *local = &p->laddr;
264 struct ip6_tnl __rcu **tp;
265 struct ip6_tnl *t;
266 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
267
268 for (tp = vti6_tnl_bucket(ip6n, p);
269 (t = rtnl_dereference(*tp)) != NULL;
270 tp = &t->next) {
271 if (ipv6_addr_equal(local, &t->parms.laddr) &&
272 ipv6_addr_equal(remote, &t->parms.raddr)) {
273 if (create)
274 return NULL;
275
276 return t;
277 }
278 }
279 if (!create)
280 return NULL;
281 return vti6_tnl_create(net, p);
282}
283
284/**
285 * vti6_dev_uninit - tunnel device uninitializer
286 * @dev: the device to be destroyed
287 *
288 * Description:
289 * vti6_dev_uninit() removes tunnel from its list
290 **/
291static void vti6_dev_uninit(struct net_device *dev)
292{
293 struct ip6_tnl *t = netdev_priv(dev);
294 struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
295
296 if (dev == ip6n->fb_tnl_dev)
297 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
298 else
299 vti6_tnl_unlink(ip6n, t);
300 dev_put(dev);
301}
302
303static int vti6_rcv(struct sk_buff *skb)
304{
305 struct ip6_tnl *t;
306 const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
307
308 rcu_read_lock();
309 t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
310 if (t) {
311 if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
312 rcu_read_unlock();
313 goto discard;
314 }
315
316 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
317 rcu_read_unlock();
318 return 0;
319 }
320
321 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
322 t->dev->stats.rx_dropped++;
323 rcu_read_unlock();
324 goto discard;
325 }
326
327 rcu_read_unlock();
328
329 return xfrm6_rcv_tnl(skb, t);
330 }
331 rcu_read_unlock();
332 return -EINVAL;
333discard:
334 kfree_skb(skb);
335 return 0;
336}
337
338static int vti6_rcv_cb(struct sk_buff *skb, int err)
339{
340 unsigned short family;
341 struct net_device *dev;
342 struct pcpu_sw_netstats *tstats;
343 struct xfrm_state *x;
344 struct xfrm_mode *inner_mode;
345 struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
346 u32 orig_mark = skb->mark;
347 int ret;
348
349 if (!t)
350 return 1;
351
352 dev = t->dev;
353
354 if (err) {
355 dev->stats.rx_errors++;
356 dev->stats.rx_dropped++;
357
358 return 0;
359 }
360
361 x = xfrm_input_state(skb);
362
363 inner_mode = x->inner_mode;
364
365 if (x->sel.family == AF_UNSPEC) {
366 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
367 if (inner_mode == NULL) {
368 XFRM_INC_STATS(dev_net(skb->dev),
369 LINUX_MIB_XFRMINSTATEMODEERROR);
370 return -EINVAL;
371 }
372 }
373
374 family = inner_mode->afinfo->family;
375
376 skb->mark = be32_to_cpu(t->parms.i_key);
377 ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
378 skb->mark = orig_mark;
379
380 if (!ret)
381 return -EPERM;
382
383 skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
384 skb->dev = dev;
385
386 tstats = this_cpu_ptr(dev->tstats);
387 u64_stats_update_begin(&tstats->syncp);
388 tstats->rx_packets++;
389 tstats->rx_bytes += skb->len;
390 u64_stats_update_end(&tstats->syncp);
391
392 return 0;
393}
394
395/**
396 * vti6_addr_conflict - compare packet addresses to tunnel's own
397 * @t: the outgoing tunnel device
398 * @hdr: IPv6 header from the incoming packet
399 *
400 * Description:
401 * Avoid trivial tunneling loop by checking that tunnel exit-point
402 * doesn't match source of incoming packet.
403 *
404 * Return:
405 * 1 if conflict,
406 * 0 else
407 **/
408static inline bool
409vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
410{
411 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
412}
413
414static bool vti6_state_check(const struct xfrm_state *x,
415 const struct in6_addr *dst,
416 const struct in6_addr *src)
417{
418 xfrm_address_t *daddr = (xfrm_address_t *)dst;
419 xfrm_address_t *saddr = (xfrm_address_t *)src;
420
421 /* if there is no transform then this tunnel is not functional.
422 * Or if the xfrm is not mode tunnel.
423 */
424 if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
425 x->props.family != AF_INET6)
426 return false;
427
428 if (ipv6_addr_any(dst))
429 return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
430
431 if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
432 return false;
433
434 return true;
435}
436
437/**
438 * vti6_xmit - send a packet
439 * @skb: the outgoing socket buffer
440 * @dev: the outgoing tunnel device
441 * @fl: the flow informations for the xfrm_lookup
442 **/
443static int
444vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
445{
446 struct ip6_tnl *t = netdev_priv(dev);
447 struct net_device_stats *stats = &t->dev->stats;
448 struct dst_entry *dst = skb_dst(skb);
449 struct net_device *tdev;
450 struct xfrm_state *x;
451 int pkt_len = skb->len;
452 int err = -1;
453 int mtu;
454
455 if (!dst)
456 goto tx_err_link_failure;
457
458 dst_hold(dst);
459 dst = xfrm_lookup(t->net, dst, fl, NULL, 0);
460 if (IS_ERR(dst)) {
461 err = PTR_ERR(dst);
462 dst = NULL;
463 goto tx_err_link_failure;
464 }
465
466 x = dst->xfrm;
467 if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr))
468 goto tx_err_link_failure;
469
470 if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr,
471 (const struct in6_addr *)&x->id.daddr))
472 goto tx_err_link_failure;
473
474 tdev = dst->dev;
475
476 if (tdev == dev) {
477 stats->collisions++;
478 net_warn_ratelimited("%s: Local routing loop detected!\n",
479 t->parms.name);
480 goto tx_err_dst_release;
481 }
482
483 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
484 skb_dst_set(skb, dst);
485 skb->dev = skb_dst(skb)->dev;
486
487 mtu = dst_mtu(dst);
488 if (!skb->ignore_df && skb->len > mtu) {
489 skb_dst_update_pmtu(skb, mtu);
490
491 if (skb->protocol == htons(ETH_P_IPV6)) {
492 if (mtu < IPV6_MIN_MTU)
493 mtu = IPV6_MIN_MTU;
494
495 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
496 } else {
497 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
498 htonl(mtu));
499 }
500
501 return -EMSGSIZE;
502 }
503
504 err = dst_output(t->net, skb->sk, skb);
505 if (net_xmit_eval(err) == 0) {
506 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
507
508 u64_stats_update_begin(&tstats->syncp);
509 tstats->tx_bytes += pkt_len;
510 tstats->tx_packets++;
511 u64_stats_update_end(&tstats->syncp);
512 } else {
513 stats->tx_errors++;
514 stats->tx_aborted_errors++;
515 }
516
517 return 0;
518tx_err_link_failure:
519 stats->tx_carrier_errors++;
520 dst_link_failure(skb);
521tx_err_dst_release:
522 dst_release(dst);
523 return err;
524}
525
526static netdev_tx_t
527vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
528{
529 struct ip6_tnl *t = netdev_priv(dev);
530 struct net_device_stats *stats = &t->dev->stats;
531 struct ipv6hdr *ipv6h;
532 struct flowi fl;
533 int ret;
534
535 memset(&fl, 0, sizeof(fl));
536
537 switch (skb->protocol) {
538 case htons(ETH_P_IPV6):
539 ipv6h = ipv6_hdr(skb);
540
541 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
542 vti6_addr_conflict(t, ipv6h))
543 goto tx_err;
544
545 xfrm_decode_session(skb, &fl, AF_INET6);
546 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
547 break;
548 case htons(ETH_P_IP):
549 xfrm_decode_session(skb, &fl, AF_INET);
550 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
551 break;
552 default:
553 goto tx_err;
554 }
555
556 /* override mark with tunnel output key */
557 fl.flowi_mark = be32_to_cpu(t->parms.o_key);
558
559 ret = vti6_xmit(skb, dev, &fl);
560 if (ret < 0)
561 goto tx_err;
562
563 return NETDEV_TX_OK;
564
565tx_err:
566 stats->tx_errors++;
567 stats->tx_dropped++;
568 kfree_skb(skb);
569 return NETDEV_TX_OK;
570}
571
572static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
573 u8 type, u8 code, int offset, __be32 info)
574{
575 __be32 spi;
576 __u32 mark;
577 struct xfrm_state *x;
578 struct ip6_tnl *t;
579 struct ip_esp_hdr *esph;
580 struct ip_auth_hdr *ah;
581 struct ip_comp_hdr *ipch;
582 struct net *net = dev_net(skb->dev);
583 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
584 int protocol = iph->nexthdr;
585
586 t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
587 if (!t)
588 return -1;
589
590 mark = be32_to_cpu(t->parms.o_key);
591
592 switch (protocol) {
593 case IPPROTO_ESP:
594 esph = (struct ip_esp_hdr *)(skb->data + offset);
595 spi = esph->spi;
596 break;
597 case IPPROTO_AH:
598 ah = (struct ip_auth_hdr *)(skb->data + offset);
599 spi = ah->spi;
600 break;
601 case IPPROTO_COMP:
602 ipch = (struct ip_comp_hdr *)(skb->data + offset);
603 spi = htonl(ntohs(ipch->cpi));
604 break;
605 default:
606 return 0;
607 }
608
609 if (type != ICMPV6_PKT_TOOBIG &&
610 type != NDISC_REDIRECT)
611 return 0;
612
613 x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
614 spi, protocol, AF_INET6);
615 if (!x)
616 return 0;
617
618 if (type == NDISC_REDIRECT)
619 ip6_redirect(skb, net, skb->dev->ifindex, 0,
620 sock_net_uid(net, NULL));
621 else
622 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
623 xfrm_state_put(x);
624
625 return 0;
626}
627
628static void vti6_link_config(struct ip6_tnl *t, bool keep_mtu)
629{
630 struct net_device *dev = t->dev;
631 struct __ip6_tnl_parm *p = &t->parms;
632 struct net_device *tdev = NULL;
633 int mtu;
634
635 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
636 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
637
638 p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
639 IP6_TNL_F_CAP_PER_PACKET);
640 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
641
642 if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
643 dev->flags |= IFF_POINTOPOINT;
644 else
645 dev->flags &= ~IFF_POINTOPOINT;
646
647 if (keep_mtu && dev->mtu) {
648 dev->mtu = clamp(dev->mtu, dev->min_mtu, dev->max_mtu);
649 return;
650 }
651
652 if (p->flags & IP6_TNL_F_CAP_XMIT) {
653 int strict = (ipv6_addr_type(&p->raddr) &
654 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
655 struct rt6_info *rt = rt6_lookup(t->net,
656 &p->raddr, &p->laddr,
657 p->link, NULL, strict);
658
659 if (rt)
660 tdev = rt->dst.dev;
661 ip6_rt_put(rt);
662 }
663
664 if (!tdev && p->link)
665 tdev = __dev_get_by_index(t->net, p->link);
666
667 if (tdev)
668 mtu = tdev->mtu - sizeof(struct ipv6hdr);
669 else
670 mtu = ETH_DATA_LEN - LL_MAX_HEADER - sizeof(struct ipv6hdr);
671
672 dev->mtu = max_t(int, mtu, IPV4_MIN_MTU);
673}
674
675/**
676 * vti6_tnl_change - update the tunnel parameters
677 * @t: tunnel to be changed
678 * @p: tunnel configuration parameters
679 * @keep_mtu: MTU was set from userspace, don't re-compute it
680 *
681 * Description:
682 * vti6_tnl_change() updates the tunnel parameters
683 **/
684static int
685vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
686 bool keep_mtu)
687{
688 t->parms.laddr = p->laddr;
689 t->parms.raddr = p->raddr;
690 t->parms.link = p->link;
691 t->parms.i_key = p->i_key;
692 t->parms.o_key = p->o_key;
693 t->parms.proto = p->proto;
694 t->parms.fwmark = p->fwmark;
695 dst_cache_reset(&t->dst_cache);
696 vti6_link_config(t, keep_mtu);
697 return 0;
698}
699
700static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p,
701 bool keep_mtu)
702{
703 struct net *net = dev_net(t->dev);
704 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
705 int err;
706
707 vti6_tnl_unlink(ip6n, t);
708 synchronize_net();
709 err = vti6_tnl_change(t, p, keep_mtu);
710 vti6_tnl_link(ip6n, t);
711 netdev_state_change(t->dev);
712 return err;
713}
714
715static void
716vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
717{
718 p->laddr = u->laddr;
719 p->raddr = u->raddr;
720 p->link = u->link;
721 p->i_key = u->i_key;
722 p->o_key = u->o_key;
723 p->proto = u->proto;
724
725 memcpy(p->name, u->name, sizeof(u->name));
726}
727
728static void
729vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
730{
731 u->laddr = p->laddr;
732 u->raddr = p->raddr;
733 u->link = p->link;
734 u->i_key = p->i_key;
735 u->o_key = p->o_key;
736 if (u->i_key)
737 u->i_flags |= GRE_KEY;
738 if (u->o_key)
739 u->o_flags |= GRE_KEY;
740 u->proto = p->proto;
741
742 memcpy(u->name, p->name, sizeof(u->name));
743}
744
745/**
746 * vti6_tnl_ioctl - configure vti6 tunnels from userspace
747 * @dev: virtual device associated with tunnel
748 * @ifr: parameters passed from userspace
749 * @cmd: command to be performed
750 *
751 * Description:
752 * vti6_ioctl() is used for managing vti6 tunnels
753 * from userspace.
754 *
755 * The possible commands are the following:
756 * %SIOCGETTUNNEL: get tunnel parameters for device
757 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
758 * %SIOCCHGTUNNEL: change tunnel parameters to those given
759 * %SIOCDELTUNNEL: delete tunnel
760 *
761 * The fallback device "ip6_vti0", created during module
762 * initialization, can be used for creating other tunnel devices.
763 *
764 * Return:
765 * 0 on success,
766 * %-EFAULT if unable to copy data to or from userspace,
767 * %-EPERM if current process hasn't %CAP_NET_ADMIN set
768 * %-EINVAL if passed tunnel parameters are invalid,
769 * %-EEXIST if changing a tunnel's parameters would cause a conflict
770 * %-ENODEV if attempting to change or delete a nonexisting device
771 **/
772static int
773vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
774{
775 int err = 0;
776 struct ip6_tnl_parm2 p;
777 struct __ip6_tnl_parm p1;
778 struct ip6_tnl *t = NULL;
779 struct net *net = dev_net(dev);
780 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
781
782 switch (cmd) {
783 case SIOCGETTUNNEL:
784 if (dev == ip6n->fb_tnl_dev) {
785 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
786 err = -EFAULT;
787 break;
788 }
789 vti6_parm_from_user(&p1, &p);
790 t = vti6_locate(net, &p1, 0);
791 } else {
792 memset(&p, 0, sizeof(p));
793 }
794 if (!t)
795 t = netdev_priv(dev);
796 vti6_parm_to_user(&p, &t->parms);
797 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
798 err = -EFAULT;
799 break;
800 case SIOCADDTUNNEL:
801 case SIOCCHGTUNNEL:
802 err = -EPERM;
803 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
804 break;
805 err = -EFAULT;
806 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
807 break;
808 err = -EINVAL;
809 if (p.proto != IPPROTO_IPV6 && p.proto != 0)
810 break;
811 vti6_parm_from_user(&p1, &p);
812 t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
813 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
814 if (t) {
815 if (t->dev != dev) {
816 err = -EEXIST;
817 break;
818 }
819 } else
820 t = netdev_priv(dev);
821
822 err = vti6_update(t, &p1, false);
823 }
824 if (t) {
825 err = 0;
826 vti6_parm_to_user(&p, &t->parms);
827 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
828 err = -EFAULT;
829
830 } else
831 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
832 break;
833 case SIOCDELTUNNEL:
834 err = -EPERM;
835 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
836 break;
837
838 if (dev == ip6n->fb_tnl_dev) {
839 err = -EFAULT;
840 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
841 break;
842 err = -ENOENT;
843 vti6_parm_from_user(&p1, &p);
844 t = vti6_locate(net, &p1, 0);
845 if (!t)
846 break;
847 err = -EPERM;
848 if (t->dev == ip6n->fb_tnl_dev)
849 break;
850 dev = t->dev;
851 }
852 err = 0;
853 unregister_netdevice(dev);
854 break;
855 default:
856 err = -EINVAL;
857 }
858 return err;
859}
860
861static const struct net_device_ops vti6_netdev_ops = {
862 .ndo_init = vti6_dev_init,
863 .ndo_uninit = vti6_dev_uninit,
864 .ndo_start_xmit = vti6_tnl_xmit,
865 .ndo_do_ioctl = vti6_ioctl,
866 .ndo_get_stats64 = ip_tunnel_get_stats64,
867 .ndo_get_iflink = ip6_tnl_get_iflink,
868};
869
870/**
871 * vti6_dev_setup - setup virtual tunnel device
872 * @dev: virtual device associated with tunnel
873 *
874 * Description:
875 * Initialize function pointers and device parameters
876 **/
877static void vti6_dev_setup(struct net_device *dev)
878{
879 dev->netdev_ops = &vti6_netdev_ops;
880 dev->needs_free_netdev = true;
881 dev->priv_destructor = vti6_dev_free;
882
883 dev->type = ARPHRD_TUNNEL6;
884 dev->min_mtu = IPV4_MIN_MTU;
885 dev->max_mtu = IP_MAX_MTU - sizeof(struct ipv6hdr);
886 dev->flags |= IFF_NOARP;
887 dev->addr_len = sizeof(struct in6_addr);
888 netif_keep_dst(dev);
889 /* This perm addr will be used as interface identifier by IPv6 */
890 dev->addr_assign_type = NET_ADDR_RANDOM;
891 eth_random_addr(dev->perm_addr);
892}
893
894/**
895 * vti6_dev_init_gen - general initializer for all tunnel devices
896 * @dev: virtual device associated with tunnel
897 **/
898static inline int vti6_dev_init_gen(struct net_device *dev)
899{
900 struct ip6_tnl *t = netdev_priv(dev);
901
902 t->dev = dev;
903 t->net = dev_net(dev);
904 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
905 if (!dev->tstats)
906 return -ENOMEM;
907 return 0;
908}
909
910/**
911 * vti6_dev_init - initializer for all non fallback tunnel devices
912 * @dev: virtual device associated with tunnel
913 **/
914static int vti6_dev_init(struct net_device *dev)
915{
916 struct ip6_tnl *t = netdev_priv(dev);
917 int err = vti6_dev_init_gen(dev);
918
919 if (err)
920 return err;
921 vti6_link_config(t, true);
922 return 0;
923}
924
925/**
926 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device
927 * @dev: fallback device
928 *
929 * Return: 0
930 **/
931static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
932{
933 struct ip6_tnl *t = netdev_priv(dev);
934 struct net *net = dev_net(dev);
935 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
936
937 t->parms.proto = IPPROTO_IPV6;
938 dev_hold(dev);
939
940 rcu_assign_pointer(ip6n->tnls_wc[0], t);
941 return 0;
942}
943
944static int vti6_validate(struct nlattr *tb[], struct nlattr *data[],
945 struct netlink_ext_ack *extack)
946{
947 return 0;
948}
949
950static void vti6_netlink_parms(struct nlattr *data[],
951 struct __ip6_tnl_parm *parms)
952{
953 memset(parms, 0, sizeof(*parms));
954
955 if (!data)
956 return;
957
958 if (data[IFLA_VTI_LINK])
959 parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
960
961 if (data[IFLA_VTI_LOCAL])
962 parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]);
963
964 if (data[IFLA_VTI_REMOTE])
965 parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]);
966
967 if (data[IFLA_VTI_IKEY])
968 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
969
970 if (data[IFLA_VTI_OKEY])
971 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
972
973 if (data[IFLA_VTI_FWMARK])
974 parms->fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
975}
976
977static int vti6_newlink(struct net *src_net, struct net_device *dev,
978 struct nlattr *tb[], struct nlattr *data[],
979 struct netlink_ext_ack *extack)
980{
981 struct net *net = dev_net(dev);
982 struct ip6_tnl *nt;
983
984 nt = netdev_priv(dev);
985 vti6_netlink_parms(data, &nt->parms);
986
987 nt->parms.proto = IPPROTO_IPV6;
988
989 if (vti6_locate(net, &nt->parms, 0))
990 return -EEXIST;
991
992 return vti6_tnl_create2(dev);
993}
994
995static void vti6_dellink(struct net_device *dev, struct list_head *head)
996{
997 struct net *net = dev_net(dev);
998 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
999
1000 if (dev != ip6n->fb_tnl_dev)
1001 unregister_netdevice_queue(dev, head);
1002}
1003
1004static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
1005 struct nlattr *data[],
1006 struct netlink_ext_ack *extack)
1007{
1008 struct ip6_tnl *t;
1009 struct __ip6_tnl_parm p;
1010 struct net *net = dev_net(dev);
1011 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1012
1013 if (dev == ip6n->fb_tnl_dev)
1014 return -EINVAL;
1015
1016 vti6_netlink_parms(data, &p);
1017
1018 t = vti6_locate(net, &p, 0);
1019
1020 if (t) {
1021 if (t->dev != dev)
1022 return -EEXIST;
1023 } else
1024 t = netdev_priv(dev);
1025
1026 return vti6_update(t, &p, tb && tb[IFLA_MTU]);
1027}
1028
1029static size_t vti6_get_size(const struct net_device *dev)
1030{
1031 return
1032 /* IFLA_VTI_LINK */
1033 nla_total_size(4) +
1034 /* IFLA_VTI_LOCAL */
1035 nla_total_size(sizeof(struct in6_addr)) +
1036 /* IFLA_VTI_REMOTE */
1037 nla_total_size(sizeof(struct in6_addr)) +
1038 /* IFLA_VTI_IKEY */
1039 nla_total_size(4) +
1040 /* IFLA_VTI_OKEY */
1041 nla_total_size(4) +
1042 /* IFLA_VTI_FWMARK */
1043 nla_total_size(4) +
1044 0;
1045}
1046
1047static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1048{
1049 struct ip6_tnl *tunnel = netdev_priv(dev);
1050 struct __ip6_tnl_parm *parm = &tunnel->parms;
1051
1052 if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
1053 nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) ||
1054 nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) ||
1055 nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
1056 nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key) ||
1057 nla_put_u32(skb, IFLA_VTI_FWMARK, parm->fwmark))
1058 goto nla_put_failure;
1059 return 0;
1060
1061nla_put_failure:
1062 return -EMSGSIZE;
1063}
1064
1065static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
1066 [IFLA_VTI_LINK] = { .type = NLA_U32 },
1067 [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) },
1068 [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) },
1069 [IFLA_VTI_IKEY] = { .type = NLA_U32 },
1070 [IFLA_VTI_OKEY] = { .type = NLA_U32 },
1071 [IFLA_VTI_FWMARK] = { .type = NLA_U32 },
1072};
1073
1074static struct rtnl_link_ops vti6_link_ops __read_mostly = {
1075 .kind = "vti6",
1076 .maxtype = IFLA_VTI_MAX,
1077 .policy = vti6_policy,
1078 .priv_size = sizeof(struct ip6_tnl),
1079 .setup = vti6_dev_setup,
1080 .validate = vti6_validate,
1081 .newlink = vti6_newlink,
1082 .dellink = vti6_dellink,
1083 .changelink = vti6_changelink,
1084 .get_size = vti6_get_size,
1085 .fill_info = vti6_fill_info,
1086 .get_link_net = ip6_tnl_get_link_net,
1087};
1088
1089static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n,
1090 struct list_head *list)
1091{
1092 int h;
1093 struct ip6_tnl *t;
1094
1095 for (h = 0; h < IP6_VTI_HASH_SIZE; h++) {
1096 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1097 while (t) {
1098 unregister_netdevice_queue(t->dev, list);
1099 t = rtnl_dereference(t->next);
1100 }
1101 }
1102
1103 t = rtnl_dereference(ip6n->tnls_wc[0]);
1104 unregister_netdevice_queue(t->dev, list);
1105}
1106
1107static int __net_init vti6_init_net(struct net *net)
1108{
1109 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1110 struct ip6_tnl *t = NULL;
1111 int err;
1112
1113 ip6n->tnls[0] = ip6n->tnls_wc;
1114 ip6n->tnls[1] = ip6n->tnls_r_l;
1115
1116 err = -ENOMEM;
1117 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
1118 NET_NAME_UNKNOWN, vti6_dev_setup);
1119
1120 if (!ip6n->fb_tnl_dev)
1121 goto err_alloc_dev;
1122 dev_net_set(ip6n->fb_tnl_dev, net);
1123 ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops;
1124
1125 err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1126 if (err < 0)
1127 goto err_register;
1128
1129 err = register_netdev(ip6n->fb_tnl_dev);
1130 if (err < 0)
1131 goto err_register;
1132
1133 t = netdev_priv(ip6n->fb_tnl_dev);
1134
1135 strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1136 return 0;
1137
1138err_register:
1139 free_netdev(ip6n->fb_tnl_dev);
1140err_alloc_dev:
1141 return err;
1142}
1143
1144static void __net_exit vti6_exit_batch_net(struct list_head *net_list)
1145{
1146 struct vti6_net *ip6n;
1147 struct net *net;
1148 LIST_HEAD(list);
1149
1150 rtnl_lock();
1151 list_for_each_entry(net, net_list, exit_list) {
1152 ip6n = net_generic(net, vti6_net_id);
1153 vti6_destroy_tunnels(ip6n, &list);
1154 }
1155 unregister_netdevice_many(&list);
1156 rtnl_unlock();
1157}
1158
1159static struct pernet_operations vti6_net_ops = {
1160 .init = vti6_init_net,
1161 .exit_batch = vti6_exit_batch_net,
1162 .id = &vti6_net_id,
1163 .size = sizeof(struct vti6_net),
1164};
1165
1166static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
1167 .handler = vti6_rcv,
1168 .cb_handler = vti6_rcv_cb,
1169 .err_handler = vti6_err,
1170 .priority = 100,
1171};
1172
1173static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
1174 .handler = vti6_rcv,
1175 .cb_handler = vti6_rcv_cb,
1176 .err_handler = vti6_err,
1177 .priority = 100,
1178};
1179
1180static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
1181 .handler = vti6_rcv,
1182 .cb_handler = vti6_rcv_cb,
1183 .err_handler = vti6_err,
1184 .priority = 100,
1185};
1186
1187/**
1188 * vti6_tunnel_init - register protocol and reserve needed resources
1189 *
1190 * Return: 0 on success
1191 **/
1192static int __init vti6_tunnel_init(void)
1193{
1194 const char *msg;
1195 int err;
1196
1197 msg = "tunnel device";
1198 err = register_pernet_device(&vti6_net_ops);
1199 if (err < 0)
1200 goto pernet_dev_failed;
1201
1202 msg = "tunnel protocols";
1203 err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
1204 if (err < 0)
1205 goto xfrm_proto_esp_failed;
1206 err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
1207 if (err < 0)
1208 goto xfrm_proto_ah_failed;
1209 err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
1210 if (err < 0)
1211 goto xfrm_proto_comp_failed;
1212
1213 msg = "netlink interface";
1214 err = rtnl_link_register(&vti6_link_ops);
1215 if (err < 0)
1216 goto rtnl_link_failed;
1217
1218 return 0;
1219
1220rtnl_link_failed:
1221 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1222xfrm_proto_comp_failed:
1223 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1224xfrm_proto_ah_failed:
1225 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1226xfrm_proto_esp_failed:
1227 unregister_pernet_device(&vti6_net_ops);
1228pernet_dev_failed:
1229 pr_err("vti6 init: failed to register %s\n", msg);
1230 return err;
1231}
1232
1233/**
1234 * vti6_tunnel_cleanup - free resources and unregister protocol
1235 **/
1236static void __exit vti6_tunnel_cleanup(void)
1237{
1238 rtnl_link_unregister(&vti6_link_ops);
1239 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1240 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1241 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1242 unregister_pernet_device(&vti6_net_ops);
1243}
1244
1245module_init(vti6_tunnel_init);
1246module_exit(vti6_tunnel_cleanup);
1247MODULE_LICENSE("GPL");
1248MODULE_ALIAS_RTNL_LINK("vti6");
1249MODULE_ALIAS_NETDEV("ip6_vti0");
1250MODULE_AUTHOR("Steffen Klassert");
1251MODULE_DESCRIPTION("IPv6 virtual tunnel interface");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * IPv6 virtual tunneling interface
4 *
5 * Copyright (C) 2013 secunet Security Networks AG
6 *
7 * Author:
8 * Steffen Klassert <steffen.klassert@secunet.com>
9 *
10 * Based on:
11 * net/ipv6/ip6_tunnel.c
12 */
13
14#include <linux/module.h>
15#include <linux/capability.h>
16#include <linux/errno.h>
17#include <linux/types.h>
18#include <linux/sockios.h>
19#include <linux/icmp.h>
20#include <linux/if.h>
21#include <linux/in.h>
22#include <linux/ip.h>
23#include <linux/net.h>
24#include <linux/in6.h>
25#include <linux/netdevice.h>
26#include <linux/if_arp.h>
27#include <linux/icmpv6.h>
28#include <linux/init.h>
29#include <linux/route.h>
30#include <linux/rtnetlink.h>
31#include <linux/netfilter_ipv6.h>
32#include <linux/slab.h>
33#include <linux/hash.h>
34
35#include <linux/uaccess.h>
36#include <linux/atomic.h>
37
38#include <net/icmp.h>
39#include <net/ip.h>
40#include <net/ip_tunnels.h>
41#include <net/ipv6.h>
42#include <net/ip6_route.h>
43#include <net/addrconf.h>
44#include <net/ip6_tunnel.h>
45#include <net/xfrm.h>
46#include <net/net_namespace.h>
47#include <net/netns/generic.h>
48#include <linux/etherdevice.h>
49
50#define IP6_VTI_HASH_SIZE_SHIFT 5
51#define IP6_VTI_HASH_SIZE (1 << IP6_VTI_HASH_SIZE_SHIFT)
52
53static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
54{
55 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
56
57 return hash_32(hash, IP6_VTI_HASH_SIZE_SHIFT);
58}
59
60static int vti6_dev_init(struct net_device *dev);
61static void vti6_dev_setup(struct net_device *dev);
62static struct rtnl_link_ops vti6_link_ops __read_mostly;
63
64static unsigned int vti6_net_id __read_mostly;
65struct vti6_net {
66 /* the vti6 tunnel fallback device */
67 struct net_device *fb_tnl_dev;
68 /* lists for storing tunnels in use */
69 struct ip6_tnl __rcu *tnls_r_l[IP6_VTI_HASH_SIZE];
70 struct ip6_tnl __rcu *tnls_wc[1];
71 struct ip6_tnl __rcu **tnls[2];
72};
73
74#define for_each_vti6_tunnel_rcu(start) \
75 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
76
77/**
78 * vti6_tnl_lookup - fetch tunnel matching the end-point addresses
79 * @net: network namespace
80 * @remote: the address of the tunnel exit-point
81 * @local: the address of the tunnel entry-point
82 *
83 * Return:
84 * tunnel matching given end-points if found,
85 * else fallback tunnel if its device is up,
86 * else %NULL
87 **/
88static struct ip6_tnl *
89vti6_tnl_lookup(struct net *net, const struct in6_addr *remote,
90 const struct in6_addr *local)
91{
92 unsigned int hash = HASH(remote, local);
93 struct ip6_tnl *t;
94 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
95 struct in6_addr any;
96
97 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
98 if (ipv6_addr_equal(local, &t->parms.laddr) &&
99 ipv6_addr_equal(remote, &t->parms.raddr) &&
100 (t->dev->flags & IFF_UP))
101 return t;
102 }
103
104 memset(&any, 0, sizeof(any));
105 hash = HASH(&any, local);
106 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
107 if (ipv6_addr_equal(local, &t->parms.laddr) &&
108 (t->dev->flags & IFF_UP))
109 return t;
110 }
111
112 hash = HASH(remote, &any);
113 for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
114 if (ipv6_addr_equal(remote, &t->parms.raddr) &&
115 (t->dev->flags & IFF_UP))
116 return t;
117 }
118
119 t = rcu_dereference(ip6n->tnls_wc[0]);
120 if (t && (t->dev->flags & IFF_UP))
121 return t;
122
123 return NULL;
124}
125
126/**
127 * vti6_tnl_bucket - get head of list matching given tunnel parameters
128 * @ip6n: the private data for ip6_vti in the netns
129 * @p: parameters containing tunnel end-points
130 *
131 * Description:
132 * vti6_tnl_bucket() returns the head of the list matching the
133 * &struct in6_addr entries laddr and raddr in @p.
134 *
135 * Return: head of IPv6 tunnel list
136 **/
137static struct ip6_tnl __rcu **
138vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
139{
140 const struct in6_addr *remote = &p->raddr;
141 const struct in6_addr *local = &p->laddr;
142 unsigned int h = 0;
143 int prio = 0;
144
145 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
146 prio = 1;
147 h = HASH(remote, local);
148 }
149 return &ip6n->tnls[prio][h];
150}
151
152static void
153vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
154{
155 struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
156
157 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
158 rcu_assign_pointer(*tp, t);
159}
160
161static void
162vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
163{
164 struct ip6_tnl __rcu **tp;
165 struct ip6_tnl *iter;
166
167 for (tp = vti6_tnl_bucket(ip6n, &t->parms);
168 (iter = rtnl_dereference(*tp)) != NULL;
169 tp = &iter->next) {
170 if (t == iter) {
171 rcu_assign_pointer(*tp, t->next);
172 break;
173 }
174 }
175}
176
177static void vti6_dev_free(struct net_device *dev)
178{
179 free_percpu(dev->tstats);
180}
181
182static int vti6_tnl_create2(struct net_device *dev)
183{
184 struct ip6_tnl *t = netdev_priv(dev);
185 struct net *net = dev_net(dev);
186 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
187 int err;
188
189 dev->rtnl_link_ops = &vti6_link_ops;
190 err = register_netdevice(dev);
191 if (err < 0)
192 goto out;
193
194 strcpy(t->parms.name, dev->name);
195
196 vti6_tnl_link(ip6n, t);
197
198 return 0;
199
200out:
201 return err;
202}
203
204static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
205{
206 struct net_device *dev;
207 struct ip6_tnl *t;
208 char name[IFNAMSIZ];
209 int err;
210
211 if (p->name[0]) {
212 if (!dev_valid_name(p->name))
213 goto failed;
214 strscpy(name, p->name, IFNAMSIZ);
215 } else {
216 sprintf(name, "ip6_vti%%d");
217 }
218
219 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
220 if (!dev)
221 goto failed;
222
223 dev_net_set(dev, net);
224
225 t = netdev_priv(dev);
226 t->parms = *p;
227 t->net = dev_net(dev);
228
229 err = vti6_tnl_create2(dev);
230 if (err < 0)
231 goto failed_free;
232
233 return t;
234
235failed_free:
236 free_netdev(dev);
237failed:
238 return NULL;
239}
240
241/**
242 * vti6_locate - find or create tunnel matching given parameters
243 * @net: network namespace
244 * @p: tunnel parameters
245 * @create: != 0 if allowed to create new tunnel if no match found
246 *
247 * Description:
248 * vti6_locate() first tries to locate an existing tunnel
249 * based on @parms. If this is unsuccessful, but @create is set a new
250 * tunnel device is created and registered for use.
251 *
252 * Return:
253 * matching tunnel or NULL
254 **/
255static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
256 int create)
257{
258 const struct in6_addr *remote = &p->raddr;
259 const struct in6_addr *local = &p->laddr;
260 struct ip6_tnl __rcu **tp;
261 struct ip6_tnl *t;
262 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
263
264 for (tp = vti6_tnl_bucket(ip6n, p);
265 (t = rtnl_dereference(*tp)) != NULL;
266 tp = &t->next) {
267 if (ipv6_addr_equal(local, &t->parms.laddr) &&
268 ipv6_addr_equal(remote, &t->parms.raddr)) {
269 if (create)
270 return NULL;
271
272 return t;
273 }
274 }
275 if (!create)
276 return NULL;
277 return vti6_tnl_create(net, p);
278}
279
280/**
281 * vti6_dev_uninit - tunnel device uninitializer
282 * @dev: the device to be destroyed
283 *
284 * Description:
285 * vti6_dev_uninit() removes tunnel from its list
286 **/
287static void vti6_dev_uninit(struct net_device *dev)
288{
289 struct ip6_tnl *t = netdev_priv(dev);
290 struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
291
292 if (dev == ip6n->fb_tnl_dev)
293 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
294 else
295 vti6_tnl_unlink(ip6n, t);
296 netdev_put(dev, &t->dev_tracker);
297}
298
299static int vti6_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi,
300 int encap_type)
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 goto discard;
316 }
317
318 ipv6h = ipv6_hdr(skb);
319 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
320 DEV_STATS_INC(t->dev, rx_dropped);
321 rcu_read_unlock();
322 goto discard;
323 }
324
325 rcu_read_unlock();
326
327 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
328 XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
329 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
330 return xfrm_input(skb, nexthdr, spi, encap_type);
331 }
332 rcu_read_unlock();
333 return -EINVAL;
334discard:
335 kfree_skb(skb);
336 return 0;
337}
338
339static int vti6_rcv(struct sk_buff *skb)
340{
341 int nexthdr = skb_network_header(skb)[IP6CB(skb)->nhoff];
342
343 return vti6_input_proto(skb, nexthdr, 0, 0);
344}
345
346static int vti6_rcv_cb(struct sk_buff *skb, int err)
347{
348 unsigned short family;
349 struct net_device *dev;
350 struct xfrm_state *x;
351 const struct xfrm_mode *inner_mode;
352 struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
353 u32 orig_mark = skb->mark;
354 int ret;
355
356 if (!t)
357 return 1;
358
359 dev = t->dev;
360
361 if (err) {
362 DEV_STATS_INC(dev, rx_errors);
363 DEV_STATS_INC(dev, rx_dropped);
364
365 return 0;
366 }
367
368 x = xfrm_input_state(skb);
369
370 inner_mode = &x->inner_mode;
371
372 if (x->sel.family == AF_UNSPEC) {
373 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
374 if (inner_mode == NULL) {
375 XFRM_INC_STATS(dev_net(skb->dev),
376 LINUX_MIB_XFRMINSTATEMODEERROR);
377 return -EINVAL;
378 }
379 }
380
381 family = inner_mode->family;
382
383 skb->mark = be32_to_cpu(t->parms.i_key);
384 ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
385 skb->mark = orig_mark;
386
387 if (!ret)
388 return -EPERM;
389
390 skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
391 skb->dev = dev;
392 dev_sw_netstats_rx_add(dev, skb->len);
393
394 return 0;
395}
396
397/**
398 * vti6_addr_conflict - compare packet addresses to tunnel's own
399 * @t: the outgoing tunnel device
400 * @hdr: IPv6 header from the incoming packet
401 *
402 * Description:
403 * Avoid trivial tunneling loop by checking that tunnel exit-point
404 * doesn't match source of incoming packet.
405 *
406 * Return:
407 * 1 if conflict,
408 * 0 else
409 **/
410static inline bool
411vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
412{
413 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
414}
415
416static bool vti6_state_check(const struct xfrm_state *x,
417 const struct in6_addr *dst,
418 const struct in6_addr *src)
419{
420 xfrm_address_t *daddr = (xfrm_address_t *)dst;
421 xfrm_address_t *saddr = (xfrm_address_t *)src;
422
423 /* if there is no transform then this tunnel is not functional.
424 * Or if the xfrm is not mode tunnel.
425 */
426 if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
427 x->props.family != AF_INET6)
428 return false;
429
430 if (ipv6_addr_any(dst))
431 return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
432
433 if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
434 return false;
435
436 return true;
437}
438
439/**
440 * vti6_xmit - send a packet
441 * @skb: the outgoing socket buffer
442 * @dev: the outgoing tunnel device
443 * @fl: the flow informations for the xfrm_lookup
444 **/
445static int
446vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
447{
448 struct ip6_tnl *t = netdev_priv(dev);
449 struct dst_entry *dst = skb_dst(skb);
450 struct net_device *tdev;
451 struct xfrm_state *x;
452 int pkt_len = skb->len;
453 int err = -1;
454 int mtu;
455
456 if (!dst) {
457 switch (skb->protocol) {
458 case htons(ETH_P_IP): {
459 struct rtable *rt;
460
461 fl->u.ip4.flowi4_oif = dev->ifindex;
462 fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
463 rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4);
464 if (IS_ERR(rt))
465 goto tx_err_link_failure;
466 dst = &rt->dst;
467 skb_dst_set(skb, dst);
468 break;
469 }
470 case htons(ETH_P_IPV6):
471 fl->u.ip6.flowi6_oif = dev->ifindex;
472 fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
473 dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6);
474 if (dst->error) {
475 dst_release(dst);
476 dst = NULL;
477 goto tx_err_link_failure;
478 }
479 skb_dst_set(skb, dst);
480 break;
481 default:
482 goto tx_err_link_failure;
483 }
484 }
485
486 dst_hold(dst);
487 dst = xfrm_lookup_route(t->net, dst, fl, NULL, 0);
488 if (IS_ERR(dst)) {
489 err = PTR_ERR(dst);
490 dst = NULL;
491 goto tx_err_link_failure;
492 }
493
494 if (dst->flags & DST_XFRM_QUEUE)
495 goto xmit;
496
497 x = dst->xfrm;
498 if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr))
499 goto tx_err_link_failure;
500
501 if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr,
502 (const struct in6_addr *)&x->id.daddr))
503 goto tx_err_link_failure;
504
505 tdev = dst->dev;
506
507 if (tdev == dev) {
508 DEV_STATS_INC(dev, collisions);
509 net_warn_ratelimited("%s: Local routing loop detected!\n",
510 t->parms.name);
511 goto tx_err_dst_release;
512 }
513
514 mtu = dst_mtu(dst);
515 if (skb->len > mtu) {
516 skb_dst_update_pmtu_no_confirm(skb, mtu);
517
518 if (skb->protocol == htons(ETH_P_IPV6)) {
519 if (mtu < IPV6_MIN_MTU)
520 mtu = IPV6_MIN_MTU;
521
522 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
523 } else {
524 if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
525 goto xmit;
526 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
527 htonl(mtu));
528 }
529
530 err = -EMSGSIZE;
531 goto tx_err_dst_release;
532 }
533
534xmit:
535 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
536 skb_dst_set(skb, dst);
537 skb->dev = skb_dst(skb)->dev;
538
539 err = dst_output(t->net, skb->sk, skb);
540 if (net_xmit_eval(err) == 0)
541 err = pkt_len;
542 iptunnel_xmit_stats(dev, err);
543
544 return 0;
545tx_err_link_failure:
546 DEV_STATS_INC(dev, tx_carrier_errors);
547 dst_link_failure(skb);
548tx_err_dst_release:
549 dst_release(dst);
550 return err;
551}
552
553static netdev_tx_t
554vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
555{
556 struct ip6_tnl *t = netdev_priv(dev);
557 struct flowi fl;
558 int ret;
559
560 if (!pskb_inet_may_pull(skb))
561 goto tx_err;
562
563 memset(&fl, 0, sizeof(fl));
564
565 switch (skb->protocol) {
566 case htons(ETH_P_IPV6):
567 if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
568 vti6_addr_conflict(t, ipv6_hdr(skb)))
569 goto tx_err;
570
571 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
572 xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET6);
573 break;
574 case htons(ETH_P_IP):
575 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
576 xfrm_decode_session(dev_net(dev), skb, &fl, AF_INET);
577 break;
578 default:
579 goto tx_err;
580 }
581
582 /* override mark with tunnel output key */
583 fl.flowi_mark = be32_to_cpu(t->parms.o_key);
584
585 ret = vti6_xmit(skb, dev, &fl);
586 if (ret < 0)
587 goto tx_err;
588
589 return NETDEV_TX_OK;
590
591tx_err:
592 DEV_STATS_INC(dev, tx_errors);
593 DEV_STATS_INC(dev, tx_dropped);
594 kfree_skb(skb);
595 return NETDEV_TX_OK;
596}
597
598static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
599 u8 type, u8 code, int offset, __be32 info)
600{
601 __be32 spi;
602 __u32 mark;
603 struct xfrm_state *x;
604 struct ip6_tnl *t;
605 struct ip_esp_hdr *esph;
606 struct ip_auth_hdr *ah;
607 struct ip_comp_hdr *ipch;
608 struct net *net = dev_net(skb->dev);
609 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
610 int protocol = iph->nexthdr;
611
612 t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
613 if (!t)
614 return -1;
615
616 mark = be32_to_cpu(t->parms.o_key);
617
618 switch (protocol) {
619 case IPPROTO_ESP:
620 esph = (struct ip_esp_hdr *)(skb->data + offset);
621 spi = esph->spi;
622 break;
623 case IPPROTO_AH:
624 ah = (struct ip_auth_hdr *)(skb->data + offset);
625 spi = ah->spi;
626 break;
627 case IPPROTO_COMP:
628 ipch = (struct ip_comp_hdr *)(skb->data + offset);
629 spi = htonl(ntohs(ipch->cpi));
630 break;
631 default:
632 return 0;
633 }
634
635 if (type != ICMPV6_PKT_TOOBIG &&
636 type != NDISC_REDIRECT)
637 return 0;
638
639 x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
640 spi, protocol, AF_INET6);
641 if (!x)
642 return 0;
643
644 if (type == NDISC_REDIRECT)
645 ip6_redirect(skb, net, skb->dev->ifindex, 0,
646 sock_net_uid(net, NULL));
647 else
648 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
649 xfrm_state_put(x);
650
651 return 0;
652}
653
654static void vti6_link_config(struct ip6_tnl *t, bool keep_mtu)
655{
656 struct net_device *dev = t->dev;
657 struct __ip6_tnl_parm *p = &t->parms;
658 struct net_device *tdev = NULL;
659 int mtu;
660
661 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
662 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
663
664 p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
665 IP6_TNL_F_CAP_PER_PACKET);
666 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
667
668 if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
669 dev->flags |= IFF_POINTOPOINT;
670 else
671 dev->flags &= ~IFF_POINTOPOINT;
672
673 if (keep_mtu && dev->mtu) {
674 dev->mtu = clamp(dev->mtu, dev->min_mtu, dev->max_mtu);
675 return;
676 }
677
678 if (p->flags & IP6_TNL_F_CAP_XMIT) {
679 int strict = (ipv6_addr_type(&p->raddr) &
680 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
681 struct rt6_info *rt = rt6_lookup(t->net,
682 &p->raddr, &p->laddr,
683 p->link, NULL, strict);
684
685 if (rt)
686 tdev = rt->dst.dev;
687 ip6_rt_put(rt);
688 }
689
690 if (!tdev && p->link)
691 tdev = __dev_get_by_index(t->net, p->link);
692
693 if (tdev)
694 mtu = tdev->mtu - sizeof(struct ipv6hdr);
695 else
696 mtu = ETH_DATA_LEN - LL_MAX_HEADER - sizeof(struct ipv6hdr);
697
698 dev->mtu = max_t(int, mtu, IPV4_MIN_MTU);
699}
700
701/**
702 * vti6_tnl_change - update the tunnel parameters
703 * @t: tunnel to be changed
704 * @p: tunnel configuration parameters
705 * @keep_mtu: MTU was set from userspace, don't re-compute it
706 *
707 * Description:
708 * vti6_tnl_change() updates the tunnel parameters
709 **/
710static int
711vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
712 bool keep_mtu)
713{
714 t->parms.laddr = p->laddr;
715 t->parms.raddr = p->raddr;
716 t->parms.link = p->link;
717 t->parms.i_key = p->i_key;
718 t->parms.o_key = p->o_key;
719 t->parms.proto = p->proto;
720 t->parms.fwmark = p->fwmark;
721 dst_cache_reset(&t->dst_cache);
722 vti6_link_config(t, keep_mtu);
723 return 0;
724}
725
726static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p,
727 bool keep_mtu)
728{
729 struct net *net = dev_net(t->dev);
730 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
731 int err;
732
733 vti6_tnl_unlink(ip6n, t);
734 synchronize_net();
735 err = vti6_tnl_change(t, p, keep_mtu);
736 vti6_tnl_link(ip6n, t);
737 netdev_state_change(t->dev);
738 return err;
739}
740
741static void
742vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
743{
744 p->laddr = u->laddr;
745 p->raddr = u->raddr;
746 p->link = u->link;
747 p->i_key = u->i_key;
748 p->o_key = u->o_key;
749 p->proto = u->proto;
750
751 memcpy(p->name, u->name, sizeof(u->name));
752}
753
754static void
755vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
756{
757 u->laddr = p->laddr;
758 u->raddr = p->raddr;
759 u->link = p->link;
760 u->i_key = p->i_key;
761 u->o_key = p->o_key;
762 if (u->i_key)
763 u->i_flags |= GRE_KEY;
764 if (u->o_key)
765 u->o_flags |= GRE_KEY;
766 u->proto = p->proto;
767
768 memcpy(u->name, p->name, sizeof(u->name));
769}
770
771/**
772 * vti6_siocdevprivate - configure vti6 tunnels from userspace
773 * @dev: virtual device associated with tunnel
774 * @ifr: unused
775 * @data: parameters passed from userspace
776 * @cmd: command to be performed
777 *
778 * Description:
779 * vti6_siocdevprivate() is used for managing vti6 tunnels
780 * from userspace.
781 *
782 * The possible commands are the following:
783 * %SIOCGETTUNNEL: get tunnel parameters for device
784 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
785 * %SIOCCHGTUNNEL: change tunnel parameters to those given
786 * %SIOCDELTUNNEL: delete tunnel
787 *
788 * The fallback device "ip6_vti0", created during module
789 * initialization, can be used for creating other tunnel devices.
790 *
791 * Return:
792 * 0 on success,
793 * %-EFAULT if unable to copy data to or from userspace,
794 * %-EPERM if current process hasn't %CAP_NET_ADMIN set
795 * %-EINVAL if passed tunnel parameters are invalid,
796 * %-EEXIST if changing a tunnel's parameters would cause a conflict
797 * %-ENODEV if attempting to change or delete a nonexisting device
798 **/
799static int
800vti6_siocdevprivate(struct net_device *dev, struct ifreq *ifr, void __user *data, int cmd)
801{
802 int err = 0;
803 struct ip6_tnl_parm2 p;
804 struct __ip6_tnl_parm p1;
805 struct ip6_tnl *t = NULL;
806 struct net *net = dev_net(dev);
807 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
808
809 memset(&p1, 0, sizeof(p1));
810
811 switch (cmd) {
812 case SIOCGETTUNNEL:
813 if (dev == ip6n->fb_tnl_dev) {
814 if (copy_from_user(&p, data, sizeof(p))) {
815 err = -EFAULT;
816 break;
817 }
818 vti6_parm_from_user(&p1, &p);
819 t = vti6_locate(net, &p1, 0);
820 } else {
821 memset(&p, 0, sizeof(p));
822 }
823 if (!t)
824 t = netdev_priv(dev);
825 vti6_parm_to_user(&p, &t->parms);
826 if (copy_to_user(data, &p, sizeof(p)))
827 err = -EFAULT;
828 break;
829 case SIOCADDTUNNEL:
830 case SIOCCHGTUNNEL:
831 err = -EPERM;
832 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
833 break;
834 err = -EFAULT;
835 if (copy_from_user(&p, data, sizeof(p)))
836 break;
837 err = -EINVAL;
838 if (p.proto != IPPROTO_IPV6 && p.proto != 0)
839 break;
840 vti6_parm_from_user(&p1, &p);
841 t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
842 if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
843 if (t) {
844 if (t->dev != dev) {
845 err = -EEXIST;
846 break;
847 }
848 } else
849 t = netdev_priv(dev);
850
851 err = vti6_update(t, &p1, false);
852 }
853 if (t) {
854 err = 0;
855 vti6_parm_to_user(&p, &t->parms);
856 if (copy_to_user(data, &p, sizeof(p)))
857 err = -EFAULT;
858
859 } else
860 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
861 break;
862 case SIOCDELTUNNEL:
863 err = -EPERM;
864 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
865 break;
866
867 if (dev == ip6n->fb_tnl_dev) {
868 err = -EFAULT;
869 if (copy_from_user(&p, data, sizeof(p)))
870 break;
871 err = -ENOENT;
872 vti6_parm_from_user(&p1, &p);
873 t = vti6_locate(net, &p1, 0);
874 if (!t)
875 break;
876 err = -EPERM;
877 if (t->dev == ip6n->fb_tnl_dev)
878 break;
879 dev = t->dev;
880 }
881 err = 0;
882 unregister_netdevice(dev);
883 break;
884 default:
885 err = -EINVAL;
886 }
887 return err;
888}
889
890static const struct net_device_ops vti6_netdev_ops = {
891 .ndo_init = vti6_dev_init,
892 .ndo_uninit = vti6_dev_uninit,
893 .ndo_start_xmit = vti6_tnl_xmit,
894 .ndo_siocdevprivate = vti6_siocdevprivate,
895 .ndo_get_stats64 = dev_get_tstats64,
896 .ndo_get_iflink = ip6_tnl_get_iflink,
897};
898
899/**
900 * vti6_dev_setup - setup virtual tunnel device
901 * @dev: virtual device associated with tunnel
902 *
903 * Description:
904 * Initialize function pointers and device parameters
905 **/
906static void vti6_dev_setup(struct net_device *dev)
907{
908 dev->netdev_ops = &vti6_netdev_ops;
909 dev->header_ops = &ip_tunnel_header_ops;
910 dev->needs_free_netdev = true;
911 dev->priv_destructor = vti6_dev_free;
912
913 dev->type = ARPHRD_TUNNEL6;
914 dev->min_mtu = IPV4_MIN_MTU;
915 dev->max_mtu = IP_MAX_MTU - sizeof(struct ipv6hdr);
916 dev->flags |= IFF_NOARP;
917 dev->addr_len = sizeof(struct in6_addr);
918 netif_keep_dst(dev);
919 /* This perm addr will be used as interface identifier by IPv6 */
920 dev->addr_assign_type = NET_ADDR_RANDOM;
921 eth_random_addr(dev->perm_addr);
922}
923
924/**
925 * vti6_dev_init_gen - general initializer for all tunnel devices
926 * @dev: virtual device associated with tunnel
927 **/
928static inline int vti6_dev_init_gen(struct net_device *dev)
929{
930 struct ip6_tnl *t = netdev_priv(dev);
931
932 t->dev = dev;
933 t->net = dev_net(dev);
934 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
935 if (!dev->tstats)
936 return -ENOMEM;
937 netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
938 return 0;
939}
940
941/**
942 * vti6_dev_init - initializer for all non fallback tunnel devices
943 * @dev: virtual device associated with tunnel
944 **/
945static int vti6_dev_init(struct net_device *dev)
946{
947 struct ip6_tnl *t = netdev_priv(dev);
948 int err = vti6_dev_init_gen(dev);
949
950 if (err)
951 return err;
952 vti6_link_config(t, true);
953 return 0;
954}
955
956/**
957 * vti6_fb_tnl_dev_init - initializer for fallback tunnel device
958 * @dev: fallback device
959 *
960 * Return: 0
961 **/
962static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
963{
964 struct ip6_tnl *t = netdev_priv(dev);
965 struct net *net = dev_net(dev);
966 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
967
968 t->parms.proto = IPPROTO_IPV6;
969
970 rcu_assign_pointer(ip6n->tnls_wc[0], t);
971 return 0;
972}
973
974static int vti6_validate(struct nlattr *tb[], struct nlattr *data[],
975 struct netlink_ext_ack *extack)
976{
977 return 0;
978}
979
980static void vti6_netlink_parms(struct nlattr *data[],
981 struct __ip6_tnl_parm *parms)
982{
983 memset(parms, 0, sizeof(*parms));
984
985 if (!data)
986 return;
987
988 if (data[IFLA_VTI_LINK])
989 parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
990
991 if (data[IFLA_VTI_LOCAL])
992 parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]);
993
994 if (data[IFLA_VTI_REMOTE])
995 parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]);
996
997 if (data[IFLA_VTI_IKEY])
998 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
999
1000 if (data[IFLA_VTI_OKEY])
1001 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
1002
1003 if (data[IFLA_VTI_FWMARK])
1004 parms->fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
1005}
1006
1007static int vti6_newlink(struct net *src_net, struct net_device *dev,
1008 struct nlattr *tb[], struct nlattr *data[],
1009 struct netlink_ext_ack *extack)
1010{
1011 struct net *net = dev_net(dev);
1012 struct ip6_tnl *nt;
1013
1014 nt = netdev_priv(dev);
1015 vti6_netlink_parms(data, &nt->parms);
1016
1017 nt->parms.proto = IPPROTO_IPV6;
1018
1019 if (vti6_locate(net, &nt->parms, 0))
1020 return -EEXIST;
1021
1022 return vti6_tnl_create2(dev);
1023}
1024
1025static void vti6_dellink(struct net_device *dev, struct list_head *head)
1026{
1027 struct net *net = dev_net(dev);
1028 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1029
1030 if (dev != ip6n->fb_tnl_dev)
1031 unregister_netdevice_queue(dev, head);
1032}
1033
1034static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
1035 struct nlattr *data[],
1036 struct netlink_ext_ack *extack)
1037{
1038 struct ip6_tnl *t;
1039 struct __ip6_tnl_parm p;
1040 struct net *net = dev_net(dev);
1041 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1042
1043 if (dev == ip6n->fb_tnl_dev)
1044 return -EINVAL;
1045
1046 vti6_netlink_parms(data, &p);
1047
1048 t = vti6_locate(net, &p, 0);
1049
1050 if (t) {
1051 if (t->dev != dev)
1052 return -EEXIST;
1053 } else
1054 t = netdev_priv(dev);
1055
1056 return vti6_update(t, &p, tb && tb[IFLA_MTU]);
1057}
1058
1059static size_t vti6_get_size(const struct net_device *dev)
1060{
1061 return
1062 /* IFLA_VTI_LINK */
1063 nla_total_size(4) +
1064 /* IFLA_VTI_LOCAL */
1065 nla_total_size(sizeof(struct in6_addr)) +
1066 /* IFLA_VTI_REMOTE */
1067 nla_total_size(sizeof(struct in6_addr)) +
1068 /* IFLA_VTI_IKEY */
1069 nla_total_size(4) +
1070 /* IFLA_VTI_OKEY */
1071 nla_total_size(4) +
1072 /* IFLA_VTI_FWMARK */
1073 nla_total_size(4) +
1074 0;
1075}
1076
1077static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
1078{
1079 struct ip6_tnl *tunnel = netdev_priv(dev);
1080 struct __ip6_tnl_parm *parm = &tunnel->parms;
1081
1082 if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
1083 nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) ||
1084 nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) ||
1085 nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
1086 nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key) ||
1087 nla_put_u32(skb, IFLA_VTI_FWMARK, parm->fwmark))
1088 goto nla_put_failure;
1089 return 0;
1090
1091nla_put_failure:
1092 return -EMSGSIZE;
1093}
1094
1095static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
1096 [IFLA_VTI_LINK] = { .type = NLA_U32 },
1097 [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) },
1098 [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) },
1099 [IFLA_VTI_IKEY] = { .type = NLA_U32 },
1100 [IFLA_VTI_OKEY] = { .type = NLA_U32 },
1101 [IFLA_VTI_FWMARK] = { .type = NLA_U32 },
1102};
1103
1104static struct rtnl_link_ops vti6_link_ops __read_mostly = {
1105 .kind = "vti6",
1106 .maxtype = IFLA_VTI_MAX,
1107 .policy = vti6_policy,
1108 .priv_size = sizeof(struct ip6_tnl),
1109 .setup = vti6_dev_setup,
1110 .validate = vti6_validate,
1111 .newlink = vti6_newlink,
1112 .dellink = vti6_dellink,
1113 .changelink = vti6_changelink,
1114 .get_size = vti6_get_size,
1115 .fill_info = vti6_fill_info,
1116 .get_link_net = ip6_tnl_get_link_net,
1117};
1118
1119static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n,
1120 struct list_head *list)
1121{
1122 int h;
1123 struct ip6_tnl *t;
1124
1125 for (h = 0; h < IP6_VTI_HASH_SIZE; h++) {
1126 t = rtnl_dereference(ip6n->tnls_r_l[h]);
1127 while (t) {
1128 unregister_netdevice_queue(t->dev, list);
1129 t = rtnl_dereference(t->next);
1130 }
1131 }
1132
1133 t = rtnl_dereference(ip6n->tnls_wc[0]);
1134 if (t)
1135 unregister_netdevice_queue(t->dev, list);
1136}
1137
1138static int __net_init vti6_init_net(struct net *net)
1139{
1140 struct vti6_net *ip6n = net_generic(net, vti6_net_id);
1141 struct ip6_tnl *t = NULL;
1142 int err;
1143
1144 ip6n->tnls[0] = ip6n->tnls_wc;
1145 ip6n->tnls[1] = ip6n->tnls_r_l;
1146
1147 if (!net_has_fallback_tunnels(net))
1148 return 0;
1149 err = -ENOMEM;
1150 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
1151 NET_NAME_UNKNOWN, vti6_dev_setup);
1152
1153 if (!ip6n->fb_tnl_dev)
1154 goto err_alloc_dev;
1155 dev_net_set(ip6n->fb_tnl_dev, net);
1156 ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops;
1157
1158 err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
1159 if (err < 0)
1160 goto err_register;
1161
1162 err = register_netdev(ip6n->fb_tnl_dev);
1163 if (err < 0)
1164 goto err_register;
1165
1166 t = netdev_priv(ip6n->fb_tnl_dev);
1167
1168 strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
1169 return 0;
1170
1171err_register:
1172 free_netdev(ip6n->fb_tnl_dev);
1173err_alloc_dev:
1174 return err;
1175}
1176
1177static void __net_exit vti6_exit_batch_net(struct list_head *net_list)
1178{
1179 struct vti6_net *ip6n;
1180 struct net *net;
1181 LIST_HEAD(list);
1182
1183 rtnl_lock();
1184 list_for_each_entry(net, net_list, exit_list) {
1185 ip6n = net_generic(net, vti6_net_id);
1186 vti6_destroy_tunnels(ip6n, &list);
1187 }
1188 unregister_netdevice_many(&list);
1189 rtnl_unlock();
1190}
1191
1192static struct pernet_operations vti6_net_ops = {
1193 .init = vti6_init_net,
1194 .exit_batch = vti6_exit_batch_net,
1195 .id = &vti6_net_id,
1196 .size = sizeof(struct vti6_net),
1197};
1198
1199static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
1200 .handler = vti6_rcv,
1201 .input_handler = vti6_input_proto,
1202 .cb_handler = vti6_rcv_cb,
1203 .err_handler = vti6_err,
1204 .priority = 100,
1205};
1206
1207static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
1208 .handler = vti6_rcv,
1209 .input_handler = vti6_input_proto,
1210 .cb_handler = vti6_rcv_cb,
1211 .err_handler = vti6_err,
1212 .priority = 100,
1213};
1214
1215static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
1216 .handler = vti6_rcv,
1217 .input_handler = vti6_input_proto,
1218 .cb_handler = vti6_rcv_cb,
1219 .err_handler = vti6_err,
1220 .priority = 100,
1221};
1222
1223#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1224static int vti6_rcv_tunnel(struct sk_buff *skb)
1225{
1226 const xfrm_address_t *saddr;
1227 __be32 spi;
1228
1229 saddr = (const xfrm_address_t *)&ipv6_hdr(skb)->saddr;
1230 spi = xfrm6_tunnel_spi_lookup(dev_net(skb->dev), saddr);
1231
1232 return vti6_input_proto(skb, IPPROTO_IPV6, spi, 0);
1233}
1234
1235static struct xfrm6_tunnel vti_ipv6_handler __read_mostly = {
1236 .handler = vti6_rcv_tunnel,
1237 .cb_handler = vti6_rcv_cb,
1238 .err_handler = vti6_err,
1239 .priority = 0,
1240};
1241
1242static struct xfrm6_tunnel vti_ip6ip_handler __read_mostly = {
1243 .handler = vti6_rcv_tunnel,
1244 .cb_handler = vti6_rcv_cb,
1245 .err_handler = vti6_err,
1246 .priority = 0,
1247};
1248#endif
1249
1250/**
1251 * vti6_tunnel_init - register protocol and reserve needed resources
1252 *
1253 * Return: 0 on success
1254 **/
1255static int __init vti6_tunnel_init(void)
1256{
1257 const char *msg;
1258 int err;
1259
1260 msg = "tunnel device";
1261 err = register_pernet_device(&vti6_net_ops);
1262 if (err < 0)
1263 goto pernet_dev_failed;
1264
1265 msg = "tunnel protocols";
1266 err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
1267 if (err < 0)
1268 goto xfrm_proto_esp_failed;
1269 err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
1270 if (err < 0)
1271 goto xfrm_proto_ah_failed;
1272 err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
1273 if (err < 0)
1274 goto xfrm_proto_comp_failed;
1275#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1276 msg = "ipv6 tunnel";
1277 err = xfrm6_tunnel_register(&vti_ipv6_handler, AF_INET6);
1278 if (err < 0)
1279 goto vti_tunnel_ipv6_failed;
1280 err = xfrm6_tunnel_register(&vti_ip6ip_handler, AF_INET);
1281 if (err < 0)
1282 goto vti_tunnel_ip6ip_failed;
1283#endif
1284
1285 msg = "netlink interface";
1286 err = rtnl_link_register(&vti6_link_ops);
1287 if (err < 0)
1288 goto rtnl_link_failed;
1289
1290 return 0;
1291
1292rtnl_link_failed:
1293#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1294 err = xfrm6_tunnel_deregister(&vti_ip6ip_handler, AF_INET);
1295vti_tunnel_ip6ip_failed:
1296 err = xfrm6_tunnel_deregister(&vti_ipv6_handler, AF_INET6);
1297vti_tunnel_ipv6_failed:
1298#endif
1299 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1300xfrm_proto_comp_failed:
1301 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1302xfrm_proto_ah_failed:
1303 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1304xfrm_proto_esp_failed:
1305 unregister_pernet_device(&vti6_net_ops);
1306pernet_dev_failed:
1307 pr_err("vti6 init: failed to register %s\n", msg);
1308 return err;
1309}
1310
1311/**
1312 * vti6_tunnel_cleanup - free resources and unregister protocol
1313 **/
1314static void __exit vti6_tunnel_cleanup(void)
1315{
1316 rtnl_link_unregister(&vti6_link_ops);
1317#if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL)
1318 xfrm6_tunnel_deregister(&vti_ip6ip_handler, AF_INET);
1319 xfrm6_tunnel_deregister(&vti_ipv6_handler, AF_INET6);
1320#endif
1321 xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
1322 xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
1323 xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
1324 unregister_pernet_device(&vti6_net_ops);
1325}
1326
1327module_init(vti6_tunnel_init);
1328module_exit(vti6_tunnel_cleanup);
1329MODULE_LICENSE("GPL");
1330MODULE_ALIAS_RTNL_LINK("vti6");
1331MODULE_ALIAS_NETDEV("ip6_vti0");
1332MODULE_AUTHOR("Steffen Klassert");
1333MODULE_DESCRIPTION("IPv6 virtual tunnel interface");