1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * IPv6 tunneling device
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Ville Nuorvala <vnuorval@tcs.hut.fi>
8 * Yasuyuki Kozakai <kozakai@linux-ipv6.org>
9 *
10 * Based on:
11 * linux/net/ipv6/sit.c and linux/net/ipv4/ipip.c
12 *
13 * RFC 2473
14 */
15
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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 #include <linux/etherdevice.h>
39
40 #include <linux/uaccess.h>
41 #include <linux/atomic.h>
42
43 #include <net/icmp.h>
44 #include <net/ip.h>
45 #include <net/ip_tunnels.h>
46 #include <net/ipv6.h>
47 #include <net/ip6_route.h>
48 #include <net/addrconf.h>
49 #include <net/ip6_tunnel.h>
50 #include <net/xfrm.h>
51 #include <net/dsfield.h>
52 #include <net/inet_ecn.h>
53 #include <net/net_namespace.h>
54 #include <net/netns/generic.h>
55 #include <net/dst_metadata.h>
56
57 MODULE_AUTHOR("Ville Nuorvala");
58 MODULE_DESCRIPTION("IPv6 tunneling device");
59 MODULE_LICENSE("GPL");
60 MODULE_ALIAS_RTNL_LINK("ip6tnl");
61 MODULE_ALIAS_NETDEV("ip6tnl0");
62
63 #define IP6_TUNNEL_HASH_SIZE_SHIFT 5
64 #define IP6_TUNNEL_HASH_SIZE (1 << IP6_TUNNEL_HASH_SIZE_SHIFT)
65
66 static bool log_ecn_error = true;
67 module_param(log_ecn_error, bool, 0644);
68 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
69
70 static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
71 {
72 u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
73
74 return hash_32(hash, IP6_TUNNEL_HASH_SIZE_SHIFT);
75 }
76
77 static int ip6_tnl_dev_init(struct net_device *dev);
78 static void ip6_tnl_dev_setup(struct net_device *dev);
79 static struct rtnl_link_ops ip6_link_ops __read_mostly;
80
81 static unsigned int ip6_tnl_net_id __read_mostly;
82 struct ip6_tnl_net {
83 /* the IPv6 tunnel fallback device */
84 struct net_device *fb_tnl_dev;
85 /* lists for storing tunnels in use */
86 struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE];
87 struct ip6_tnl __rcu *tnls_wc[1];
88 struct ip6_tnl __rcu **tnls[2];
89 struct ip6_tnl __rcu *collect_md_tun;
90 };
91
92 static inline int ip6_tnl_mpls_supported(void)
93 {
94 return IS_ENABLED(CONFIG_MPLS);
95 }
96
97 #define for_each_ip6_tunnel_rcu(start) \
98 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
99
100 /**
101 * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
102 * @net: network namespace
103 * @link: ifindex of underlying interface
104 * @remote: the address of the tunnel exit-point
105 * @local: the address of the tunnel entry-point
106 *
107 * Return:
108 * tunnel matching given end-points if found,
109 * else fallback tunnel if its device is up,
110 * else %NULL
111 **/
112
113 static struct ip6_tnl *
114 ip6_tnl_lookup(struct net *net, int link,
115 const struct in6_addr *remote, const struct in6_addr *local)
116 {
117 unsigned int hash = HASH(remote, local);
118 struct ip6_tnl *t, *cand = NULL;
119 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
120 struct in6_addr any;
121
122 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
123 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
124 !ipv6_addr_equal(remote, &t->parms.raddr) ||
125 !(t->dev->flags & IFF_UP))
126 continue;
127
128 if (link == t->parms.link)
129 return t;
130 else
131 cand = t;
132 }
133
134 memset(&any, 0, sizeof(any));
135 hash = HASH(&any, local);
136 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
137 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
138 !ipv6_addr_any(&t->parms.raddr) ||
139 !(t->dev->flags & IFF_UP))
140 continue;
141
142 if (link == t->parms.link)
143 return t;
144 else if (!cand)
145 cand = t;
146 }
147
148 hash = HASH(remote, &any);
149 for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
150 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
151 !ipv6_addr_any(&t->parms.laddr) ||
152 !(t->dev->flags & IFF_UP))
153 continue;
154
155 if (link == t->parms.link)
156 return t;
157 else if (!cand)
158 cand = t;
159 }
160
161 if (cand)
162 return cand;
163
164 t = rcu_dereference(ip6n->collect_md_tun);
165 if (t && t->dev->flags & IFF_UP)
166 return t;
167
168 t = rcu_dereference(ip6n->tnls_wc[0]);
169 if (t && (t->dev->flags & IFF_UP))
170 return t;
171
172 return NULL;
173 }
174
175 /**
176 * ip6_tnl_bucket - get head of list matching given tunnel parameters
177 * @ip6n: the private data for ip6_vti in the netns
178 * @p: parameters containing tunnel end-points
179 *
180 * Description:
181 * ip6_tnl_bucket() returns the head of the list matching the
182 * &struct in6_addr entries laddr and raddr in @p.
183 *
184 * Return: head of IPv6 tunnel list
185 **/
186
187 static struct ip6_tnl __rcu **
188 ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p)
189 {
190 const struct in6_addr *remote = &p->raddr;
191 const struct in6_addr *local = &p->laddr;
192 unsigned int h = 0;
193 int prio = 0;
194
195 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
196 prio = 1;
197 h = HASH(remote, local);
198 }
199 return &ip6n->tnls[prio][h];
200 }
201
202 /**
203 * ip6_tnl_link - add tunnel to hash table
204 * @ip6n: the private data for ip6_vti in the netns
205 * @t: tunnel to be added
206 **/
207
208 static void
209 ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
210 {
211 struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);
212
213 if (t->parms.collect_md)
214 rcu_assign_pointer(ip6n->collect_md_tun, t);
215 rcu_assign_pointer(t->next , rtnl_dereference(*tp));
216 rcu_assign_pointer(*tp, t);
217 }
218
219 /**
220 * ip6_tnl_unlink - remove tunnel from hash table
221 * @ip6n: the private data for ip6_vti in the netns
222 * @t: tunnel to be removed
223 **/
224
225 static void
226 ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
227 {
228 struct ip6_tnl __rcu **tp;
229 struct ip6_tnl *iter;
230
231 if (t->parms.collect_md)
232 rcu_assign_pointer(ip6n->collect_md_tun, NULL);
233
234 for (tp = ip6_tnl_bucket(ip6n, &t->parms);
235 (iter = rtnl_dereference(*tp)) != NULL;
236 tp = &iter->next) {
237 if (t == iter) {
238 rcu_assign_pointer(*tp, t->next);
239 break;
240 }
241 }
242 }
243
244 static void ip6_dev_free(struct net_device *dev)
245 {
246 struct ip6_tnl *t = netdev_priv(dev);
247
248 gro_cells_destroy(&t->gro_cells);
249 dst_cache_destroy(&t->dst_cache);
250 }
251
252 static int ip6_tnl_create2(struct net_device *dev)
253 {
254 struct ip6_tnl *t = netdev_priv(dev);
255 struct net *net = dev_net(dev);
256 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
257 int err;
258
259 dev->rtnl_link_ops = &ip6_link_ops;
260 err = register_netdevice(dev);
261 if (err < 0)
262 goto out;
263
264 strcpy(t->parms.name, dev->name);
265
266 ip6_tnl_link(ip6n, t);
267 return 0;
268
269 out:
270 return err;
271 }
272
273 /**
274 * ip6_tnl_create - create a new tunnel
275 * @net: network namespace
276 * @p: tunnel parameters
277 *
278 * Description:
279 * Create tunnel matching given parameters.
280 *
281 * Return:
282 * created tunnel or error pointer
283 **/
284
285 static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
286 {
287 struct net_device *dev;
288 struct ip6_tnl *t;
289 char name[IFNAMSIZ];
290 int err = -E2BIG;
291
292 if (p->name[0]) {
293 if (!dev_valid_name(p->name))
294 goto failed;
295 strscpy(name, p->name, IFNAMSIZ);
296 } else {
297 sprintf(name, "ip6tnl%%d");
298 }
299 err = -ENOMEM;
300 dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
301 ip6_tnl_dev_setup);
302 if (!dev)
303 goto failed;
304
305 dev_net_set(dev, net);
306
307 t = netdev_priv(dev);
308 t->parms = *p;
309 t->net = dev_net(dev);
310 err = ip6_tnl_create2(dev);
311 if (err < 0)
312 goto failed_free;
313
314 return t;
315
316 failed_free:
317 free_netdev(dev);
318 failed:
319 return ERR_PTR(err);
320 }
321
322 /**
323 * ip6_tnl_locate - find or create tunnel matching given parameters
324 * @net: network namespace
325 * @p: tunnel parameters
326 * @create: != 0 if allowed to create new tunnel if no match found
327 *
328 * Description:
329 * ip6_tnl_locate() first tries to locate an existing tunnel
330 * based on @parms. If this is unsuccessful, but @create is set a new
331 * tunnel device is created and registered for use.
332 *
333 * Return:
334 * matching tunnel or error pointer
335 **/
336
337 static struct ip6_tnl *ip6_tnl_locate(struct net *net,
338 struct __ip6_tnl_parm *p, int create)
339 {
340 const struct in6_addr *remote = &p->raddr;
341 const struct in6_addr *local = &p->laddr;
342 struct ip6_tnl __rcu **tp;
343 struct ip6_tnl *t;
344 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
345
346 for (tp = ip6_tnl_bucket(ip6n, p);
347 (t = rtnl_dereference(*tp)) != NULL;
348 tp = &t->next) {
349 if (ipv6_addr_equal(local, &t->parms.laddr) &&
350 ipv6_addr_equal(remote, &t->parms.raddr) &&
351 p->link == t->parms.link) {
352 if (create)
353 return ERR_PTR(-EEXIST);
354
355 return t;
356 }
357 }
358 if (!create)
359 return ERR_PTR(-ENODEV);
360 return ip6_tnl_create(net, p);
361 }
362
363 /**
364 * ip6_tnl_dev_uninit - tunnel device uninitializer
365 * @dev: the device to be destroyed
366 *
367 * Description:
368 * ip6_tnl_dev_uninit() removes tunnel from its list
369 **/
370
371 static void
372 ip6_tnl_dev_uninit(struct net_device *dev)
373 {
374 struct ip6_tnl *t = netdev_priv(dev);
375 struct net *net = t->net;
376 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
377
378 if (dev == ip6n->fb_tnl_dev)
379 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
380 else
381 ip6_tnl_unlink(ip6n, t);
382 dst_cache_reset(&t->dst_cache);
383 netdev_put(dev, &t->dev_tracker);
384 }
385
386 /**
387 * ip6_tnl_parse_tlv_enc_lim - handle encapsulation limit option
388 * @skb: received socket buffer
389 * @raw: the ICMPv6 error message data
390 *
391 * Return:
392 * 0 if none was found,
393 * else index to encapsulation limit
394 **/
395
396 __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw)
397 {
398 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)raw;
399 unsigned int nhoff = raw - skb->data;
400 unsigned int off = nhoff + sizeof(*ipv6h);
401 u8 nexthdr = ipv6h->nexthdr;
402
403 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
404 struct ipv6_opt_hdr *hdr;
405 u16 optlen;
406
407 if (!pskb_may_pull(skb, off + sizeof(*hdr)))
408 break;
409
410 hdr = (struct ipv6_opt_hdr *)(skb->data + off);
411 if (nexthdr == NEXTHDR_FRAGMENT) {
412 optlen = 8;
413 } else if (nexthdr == NEXTHDR_AUTH) {
414 optlen = ipv6_authlen(hdr);
415 } else {
416 optlen = ipv6_optlen(hdr);
417 }
418
419 if (!pskb_may_pull(skb, off + optlen))
420 break;
421
422 hdr = (struct ipv6_opt_hdr *)(skb->data + off);
423 if (nexthdr == NEXTHDR_FRAGMENT) {
424 struct frag_hdr *frag_hdr = (struct frag_hdr *)hdr;
425
426 if (frag_hdr->frag_off)
427 break;
428 }
429 if (nexthdr == NEXTHDR_DEST) {
430 u16 i = 2;
431
432 while (1) {
433 struct ipv6_tlv_tnl_enc_lim *tel;
434
435 /* No more room for encapsulation limit */
436 if (i + sizeof(*tel) > optlen)
437 break;
438
439 tel = (struct ipv6_tlv_tnl_enc_lim *)(skb->data + off + i);
440 /* return index of option if found and valid */
441 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
442 tel->length == 1)
443 return i + off - nhoff;
444 /* else jump to next option */
445 if (tel->type)
446 i += tel->length + 2;
447 else
448 i++;
449 }
450 }
451 nexthdr = hdr->nexthdr;
452 off += optlen;
453 }
454 return 0;
455 }
456 EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim);
457
458 /* ip6_tnl_err() should handle errors in the tunnel according to the
459 * specifications in RFC 2473.
460 */
461 static int
462 ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
463 u8 *type, u8 *code, int *msg, __u32 *info, int offset)
464 {
465 const struct ipv6hdr *ipv6h = (const struct ipv6hdr *)skb->data;
466 struct net *net = dev_net(skb->dev);
467 u8 rel_type = ICMPV6_DEST_UNREACH;
468 u8 rel_code = ICMPV6_ADDR_UNREACH;
469 __u32 rel_info = 0;
470 struct ip6_tnl *t;
471 int err = -ENOENT;
472 int rel_msg = 0;
473 u8 tproto;
474 __u16 len;
475
476 /* If the packet doesn't contain the original IPv6 header we are
477 in trouble since we might need the source address for further
478 processing of the error. */
479
480 rcu_read_lock();
481 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->daddr, &ipv6h->saddr);
482 if (!t)
483 goto out;
484
485 tproto = READ_ONCE(t->parms.proto);
486 if (tproto != ipproto && tproto != 0)
487 goto out;
488
489 err = 0;
490
491 switch (*type) {
492 case ICMPV6_DEST_UNREACH:
493 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
494 t->parms.name);
495 rel_msg = 1;
496 break;
497 case ICMPV6_TIME_EXCEED:
498 if ((*code) == ICMPV6_EXC_HOPLIMIT) {
499 net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
500 t->parms.name);
501 rel_msg = 1;
502 }
503 break;
504 case ICMPV6_PARAMPROB: {
505 struct ipv6_tlv_tnl_enc_lim *tel;
506 __u32 teli;
507
508 teli = 0;
509 if ((*code) == ICMPV6_HDR_FIELD)
510 teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
511
512 if (teli && teli == *info - 2) {
513 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
514 if (tel->encap_limit == 0) {
515 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
516 t->parms.name);
517 rel_msg = 1;
518 }
519 } else {
520 net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
521 t->parms.name);
522 }
523 break;
524 }
525 case ICMPV6_PKT_TOOBIG: {
526 __u32 mtu;
527
528 ip6_update_pmtu(skb, net, htonl(*info), 0, 0,
529 sock_net_uid(net, NULL));
530 mtu = *info - offset;
531 if (mtu < IPV6_MIN_MTU)
532 mtu = IPV6_MIN_MTU;
533 len = sizeof(*ipv6h) + ntohs(ipv6h->payload_len);
534 if (len > mtu) {
535 rel_type = ICMPV6_PKT_TOOBIG;
536 rel_code = 0;
537 rel_info = mtu;
538 rel_msg = 1;
539 }
540 break;
541 }
542 case NDISC_REDIRECT:
543 ip6_redirect(skb, net, skb->dev->ifindex, 0,
544 sock_net_uid(net, NULL));
545 break;
546 }
547
548 *type = rel_type;
549 *code = rel_code;
550 *info = rel_info;
551 *msg = rel_msg;
552
553 out:
554 rcu_read_unlock();
555 return err;
556 }
557
558 static int
559 ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
560 u8 type, u8 code, int offset, __be32 info)
561 {
562 __u32 rel_info = ntohl(info);
563 const struct iphdr *eiph;
564 struct sk_buff *skb2;
565 int err, rel_msg = 0;
566 u8 rel_type = type;
567 u8 rel_code = code;
568 struct rtable *rt;
569 struct flowi4 fl4;
570
571 err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
572 &rel_msg, &rel_info, offset);
573 if (err < 0)
574 return err;
575
576 if (rel_msg == 0)
577 return 0;
578
579 switch (rel_type) {
580 case ICMPV6_DEST_UNREACH:
581 if (rel_code != ICMPV6_ADDR_UNREACH)
582 return 0;
583 rel_type = ICMP_DEST_UNREACH;
584 rel_code = ICMP_HOST_UNREACH;
585 break;
586 case ICMPV6_PKT_TOOBIG:
587 if (rel_code != 0)
588 return 0;
589 rel_type = ICMP_DEST_UNREACH;
590 rel_code = ICMP_FRAG_NEEDED;
591 break;
592 default:
593 return 0;
594 }
595
596 if (!pskb_may_pull(skb, offset + sizeof(struct iphdr)))
597 return 0;
598
599 skb2 = skb_clone(skb, GFP_ATOMIC);
600 if (!skb2)
601 return 0;
602
603 skb_dst_drop(skb2);
604
605 skb_pull(skb2, offset);
606 skb_reset_network_header(skb2);
607 eiph = ip_hdr(skb2);
608
609 /* Try to guess incoming interface */
610 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, eiph->saddr,
611 0, 0, 0, IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
612 if (IS_ERR(rt))
613 goto out;
614
615 skb2->dev = rt->dst.dev;
616 ip_rt_put(rt);
617
618 /* route "incoming" packet */
619 if (rt->rt_flags & RTCF_LOCAL) {
620 rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL,
621 eiph->daddr, eiph->saddr, 0, 0,
622 IPPROTO_IPIP, RT_TOS(eiph->tos), 0);
623 if (IS_ERR(rt) || rt->dst.dev->type != ARPHRD_TUNNEL6) {
624 if (!IS_ERR(rt))
625 ip_rt_put(rt);
626 goto out;
627 }
628 skb_dst_set(skb2, &rt->dst);
629 } else {
630 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos,
631 skb2->dev) ||
632 skb_dst(skb2)->dev->type != ARPHRD_TUNNEL6)
633 goto out;
634 }
635
636 /* change mtu on this route */
637 if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) {
638 if (rel_info > dst_mtu(skb_dst(skb2)))
639 goto out;
640
641 skb_dst_update_pmtu_no_confirm(skb2, rel_info);
642 }
643
644 icmp_send(skb2, rel_type, rel_code, htonl(rel_info));
645
646 out:
647 kfree_skb(skb2);
648 return 0;
649 }
650
651 static int
652 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
653 u8 type, u8 code, int offset, __be32 info)
654 {
655 __u32 rel_info = ntohl(info);
656 int err, rel_msg = 0;
657 u8 rel_type = type;
658 u8 rel_code = code;
659
660 err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
661 &rel_msg, &rel_info, offset);
662 if (err < 0)
663 return err;
664
665 if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) {
666 struct rt6_info *rt;
667 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
668
669 if (!skb2)
670 return 0;
671
672 skb_dst_drop(skb2);
673 skb_pull(skb2, offset);
674 skb_reset_network_header(skb2);
675
676 /* Try to guess incoming interface */
677 rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr,
678 NULL, 0, skb2, 0);
679
680 if (rt && rt->dst.dev)
681 skb2->dev = rt->dst.dev;
682
683 icmpv6_send(skb2, rel_type, rel_code, rel_info);
684
685 ip6_rt_put(rt);
686
687 kfree_skb(skb2);
688 }
689
690 return 0;
691 }
692
693 static int
694 mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
695 u8 type, u8 code, int offset, __be32 info)
696 {
697 __u32 rel_info = ntohl(info);
698 int err, rel_msg = 0;
699 u8 rel_type = type;
700 u8 rel_code = code;
701
702 err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code,
703 &rel_msg, &rel_info, offset);
704 return err;
705 }
706
707 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
708 const struct ipv6hdr *ipv6h,
709 struct sk_buff *skb)
710 {
711 __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK;
712
713 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
714 ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield);
715
716 return IP6_ECN_decapsulate(ipv6h, skb);
717 }
718
719 static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
720 const struct ipv6hdr *ipv6h,
721 struct sk_buff *skb)
722 {
723 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
724 ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb));
725
726 return IP6_ECN_decapsulate(ipv6h, skb);
727 }
728
729 static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
730 const struct ipv6hdr *ipv6h,
731 struct sk_buff *skb)
732 {
733 /* ECN is not supported in AF_MPLS */
734 return 0;
735 }
736
737 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
738 const struct in6_addr *laddr,
739 const struct in6_addr *raddr)
740 {
741 struct __ip6_tnl_parm *p = &t->parms;
742 int ltype = ipv6_addr_type(laddr);
743 int rtype = ipv6_addr_type(raddr);
744 __u32 flags = 0;
745
746 if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) {
747 flags = IP6_TNL_F_CAP_PER_PACKET;
748 } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
749 rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) &&
750 !((ltype|rtype) & IPV6_ADDR_LOOPBACK) &&
751 (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) {
752 if (ltype&IPV6_ADDR_UNICAST)
753 flags |= IP6_TNL_F_CAP_XMIT;
754 if (rtype&IPV6_ADDR_UNICAST)
755 flags |= IP6_TNL_F_CAP_RCV;
756 }
757 return flags;
758 }
759 EXPORT_SYMBOL(ip6_tnl_get_cap);
760
761 /* called with rcu_read_lock() */
762 int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
763 const struct in6_addr *laddr,
764 const struct in6_addr *raddr)
765 {
766 struct __ip6_tnl_parm *p = &t->parms;
767 int ret = 0;
768 struct net *net = t->net;
769
770 if ((p->flags & IP6_TNL_F_CAP_RCV) ||
771 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
772 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) {
773 struct net_device *ldev = NULL;
774
775 if (p->link)
776 ldev = dev_get_by_index_rcu(net, p->link);
777
778 if ((ipv6_addr_is_multicast(laddr) ||
779 likely(ipv6_chk_addr_and_flags(net, laddr, ldev, false,
780 0, IFA_F_TENTATIVE))) &&
781 ((p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) ||
782 likely(!ipv6_chk_addr_and_flags(net, raddr, ldev, true,
783 0, IFA_F_TENTATIVE))))
784 ret = 1;
785 }
786 return ret;
787 }
788 EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
789
790 static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
791 const struct tnl_ptk_info *tpi,
792 struct metadata_dst *tun_dst,
793 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
794 const struct ipv6hdr *ipv6h,
795 struct sk_buff *skb),
796 bool log_ecn_err)
797 {
798 const struct ipv6hdr *ipv6h;
799 int nh, err;
800
801 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.i_flags) !=
802 test_bit(IP_TUNNEL_CSUM_BIT, tpi->flags)) {
803 DEV_STATS_INC(tunnel->dev, rx_crc_errors);
804 DEV_STATS_INC(tunnel->dev, rx_errors);
805 goto drop;
806 }
807
808 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.i_flags)) {
809 if (!test_bit(IP_TUNNEL_SEQ_BIT, tpi->flags) ||
810 (tunnel->i_seqno &&
811 (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
812 DEV_STATS_INC(tunnel->dev, rx_fifo_errors);
813 DEV_STATS_INC(tunnel->dev, rx_errors);
814 goto drop;
815 }
816 tunnel->i_seqno = ntohl(tpi->seq) + 1;
817 }
818
819 skb->protocol = tpi->proto;
820
821 /* Warning: All skb pointers will be invalidated! */
822 if (tunnel->dev->type == ARPHRD_ETHER) {
823 if (!pskb_may_pull(skb, ETH_HLEN)) {
824 DEV_STATS_INC(tunnel->dev, rx_length_errors);
825 DEV_STATS_INC(tunnel->dev, rx_errors);
826 goto drop;
827 }
828
829 skb->protocol = eth_type_trans(skb, tunnel->dev);
830 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
831 } else {
832 skb->dev = tunnel->dev;
833 skb_reset_mac_header(skb);
834 }
835
836 /* Save offset of outer header relative to skb->head,
837 * because we are going to reset the network header to the inner header
838 * and might change skb->head.
839 */
840 nh = skb_network_header(skb) - skb->head;
841
842 skb_reset_network_header(skb);
843
844 if (!pskb_inet_may_pull(skb)) {
845 DEV_STATS_INC(tunnel->dev, rx_length_errors);
846 DEV_STATS_INC(tunnel->dev, rx_errors);
847 goto drop;
848 }
849
850 /* Get the outer header. */
851 ipv6h = (struct ipv6hdr *)(skb->head + nh);
852
853 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
854
855 __skb_tunnel_rx(skb, tunnel->dev, tunnel->net);
856
857 err = dscp_ecn_decapsulate(tunnel, ipv6h, skb);
858 if (unlikely(err)) {
859 if (log_ecn_err)
860 net_info_ratelimited("non-ECT from %pI6 with DS=%#x\n",
861 &ipv6h->saddr,
862 ipv6_get_dsfield(ipv6h));
863 if (err > 1) {
864 DEV_STATS_INC(tunnel->dev, rx_frame_errors);
865 DEV_STATS_INC(tunnel->dev, rx_errors);
866 goto drop;
867 }
868 }
869
870 dev_sw_netstats_rx_add(tunnel->dev, skb->len);
871
872 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
873
874 if (tun_dst)
875 skb_dst_set(skb, (struct dst_entry *)tun_dst);
876
877 gro_cells_receive(&tunnel->gro_cells, skb);
878 return 0;
879
880 drop:
881 if (tun_dst)
882 dst_release((struct dst_entry *)tun_dst);
883 kfree_skb(skb);
884 return 0;
885 }
886
887 int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
888 const struct tnl_ptk_info *tpi,
889 struct metadata_dst *tun_dst,
890 bool log_ecn_err)
891 {
892 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
893 const struct ipv6hdr *ipv6h,
894 struct sk_buff *skb);
895
896 dscp_ecn_decapsulate = ip6ip6_dscp_ecn_decapsulate;
897 if (tpi->proto == htons(ETH_P_IP))
898 dscp_ecn_decapsulate = ip4ip6_dscp_ecn_decapsulate;
899
900 return __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
901 log_ecn_err);
902 }
903 EXPORT_SYMBOL(ip6_tnl_rcv);
904
905 static const struct tnl_ptk_info tpi_v6 = {
906 /* no tunnel info required for ipxip6. */
907 .proto = htons(ETH_P_IPV6),
908 };
909
910 static const struct tnl_ptk_info tpi_v4 = {
911 /* no tunnel info required for ipxip6. */
912 .proto = htons(ETH_P_IP),
913 };
914
915 static const struct tnl_ptk_info tpi_mpls = {
916 /* no tunnel info required for mplsip6. */
917 .proto = htons(ETH_P_MPLS_UC),
918 };
919
920 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
921 const struct tnl_ptk_info *tpi,
922 int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
923 const struct ipv6hdr *ipv6h,
924 struct sk_buff *skb))
925 {
926 struct ip6_tnl *t;
927 const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
928 struct metadata_dst *tun_dst = NULL;
929 int ret = -1;
930
931 rcu_read_lock();
932 t = ip6_tnl_lookup(dev_net(skb->dev), skb->dev->ifindex, &ipv6h->saddr, &ipv6h->daddr);
933
934 if (t) {
935 u8 tproto = READ_ONCE(t->parms.proto);
936
937 if (tproto != ipproto && tproto != 0)
938 goto drop;
939 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
940 goto drop;
941 ipv6h = ipv6_hdr(skb);
942 if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr))
943 goto drop;
944 if (iptunnel_pull_header(skb, 0, tpi->proto, false))
945 goto drop;
946 if (t->parms.collect_md) {
947 IP_TUNNEL_DECLARE_FLAGS(flags) = { };
948
949 tun_dst = ipv6_tun_rx_dst(skb, flags, 0, 0);
950 if (!tun_dst)
951 goto drop;
952 }
953 ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
954 log_ecn_error);
955 }
956
957 rcu_read_unlock();
958
959 return ret;
960
961 drop:
962 rcu_read_unlock();
963 kfree_skb(skb);
964 return 0;
965 }
966
967 static int ip4ip6_rcv(struct sk_buff *skb)
968 {
969 return ipxip6_rcv(skb, IPPROTO_IPIP, &tpi_v4,
970 ip4ip6_dscp_ecn_decapsulate);
971 }
972
973 static int ip6ip6_rcv(struct sk_buff *skb)
974 {
975 return ipxip6_rcv(skb, IPPROTO_IPV6, &tpi_v6,
976 ip6ip6_dscp_ecn_decapsulate);
977 }
978
979 static int mplsip6_rcv(struct sk_buff *skb)
980 {
981 return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls,
982 mplsip6_dscp_ecn_decapsulate);
983 }
984
985 struct ipv6_tel_txoption {
986 struct ipv6_txoptions ops;
987 __u8 dst_opt[8];
988 };
989
990 static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit)
991 {
992 memset(opt, 0, sizeof(struct ipv6_tel_txoption));
993
994 opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT;
995 opt->dst_opt[3] = 1;
996 opt->dst_opt[4] = encap_limit;
997 opt->dst_opt[5] = IPV6_TLV_PADN;
998 opt->dst_opt[6] = 1;
999
1000 opt->ops.dst1opt = (struct ipv6_opt_hdr *) opt->dst_opt;
1001 opt->ops.opt_nflen = 8;
1002 }
1003
1004 /**
1005 * ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
1006 * @t: the outgoing tunnel device
1007 * @hdr: IPv6 header from the incoming packet
1008 *
1009 * Description:
1010 * Avoid trivial tunneling loop by checking that tunnel exit-point
1011 * doesn't match source of incoming packet.
1012 *
1013 * Return:
1014 * 1 if conflict,
1015 * 0 else
1016 **/
1017
1018 static inline bool
1019 ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
1020 {
1021 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
1022 }
1023
1024 int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
1025 const struct in6_addr *laddr,
1026 const struct in6_addr *raddr)
1027 {
1028 struct __ip6_tnl_parm *p = &t->parms;
1029 int ret = 0;
1030 struct net *net = t->net;
1031
1032 if (t->parms.collect_md)
1033 return 1;
1034
1035 if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
1036 ((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
1037 (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {
1038 struct net_device *ldev = NULL;
1039
1040 rcu_read_lock();
1041 if (p->link)
1042 ldev = dev_get_by_index_rcu(net, p->link);
1043
1044 if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false,
1045 0, IFA_F_TENTATIVE)))
1046 pr_warn_ratelimited("%s xmit: Local address not yet configured!\n",
1047 p->name);
1048 else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) &&
1049 !ipv6_addr_is_multicast(raddr) &&
1050 unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev,
1051 true, 0, IFA_F_TENTATIVE)))
1052 pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n",
1053 p->name);
1054 else
1055 ret = 1;
1056 rcu_read_unlock();
1057 }
1058 return ret;
1059 }
1060 EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl);
1061
1062 /**
1063 * ip6_tnl_xmit - encapsulate packet and send
1064 * @skb: the outgoing socket buffer
1065 * @dev: the outgoing tunnel device
1066 * @dsfield: dscp code for outer header
1067 * @fl6: flow of tunneled packet
1068 * @encap_limit: encapsulation limit
1069 * @pmtu: Path MTU is stored if packet is too big
1070 * @proto: next header value
1071 *
1072 * Description:
1073 * Build new header and do some sanity checks on the packet before sending
1074 * it.
1075 *
1076 * Return:
1077 * 0 on success
1078 * -1 fail
1079 * %-EMSGSIZE message too big. return mtu in this case.
1080 **/
1081
1082 int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
1083 struct flowi6 *fl6, int encap_limit, __u32 *pmtu,
1084 __u8 proto)
1085 {
1086 struct ip6_tnl *t = netdev_priv(dev);
1087 struct net *net = t->net;
1088 struct ipv6hdr *ipv6h;
1089 struct ipv6_tel_txoption opt;
1090 struct dst_entry *dst = NULL, *ndst = NULL;
1091 struct net_device *tdev;
1092 int mtu;
1093 unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0;
1094 unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
1095 unsigned int max_headroom = psh_hlen;
1096 __be16 payload_protocol;
1097 bool use_cache = false;
1098 u8 hop_limit;
1099 int err = -1;
1100
1101 payload_protocol = skb_protocol(skb, true);
1102
1103 if (t->parms.collect_md) {
1104 hop_limit = skb_tunnel_info(skb)->key.ttl;
1105 goto route_lookup;
1106 } else {
1107 hop_limit = t->parms.hop_limit;
1108 }
1109
1110 /* NBMA tunnel */
1111 if (ipv6_addr_any(&t->parms.raddr)) {
1112 if (payload_protocol == htons(ETH_P_IPV6)) {
1113 struct in6_addr *addr6;
1114 struct neighbour *neigh;
1115 int addr_type;
1116
1117 if (!skb_dst(skb))
1118 goto tx_err_link_failure;
1119
1120 neigh = dst_neigh_lookup(skb_dst(skb),
1121 &ipv6_hdr(skb)->daddr);
1122 if (!neigh)
1123 goto tx_err_link_failure;
1124
1125 addr6 = (struct in6_addr *)&neigh->primary_key;
1126 addr_type = ipv6_addr_type(addr6);
1127
1128 if (addr_type == IPV6_ADDR_ANY)
1129 addr6 = &ipv6_hdr(skb)->daddr;
1130
1131 memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
1132 neigh_release(neigh);
1133 } else if (payload_protocol == htons(ETH_P_IP)) {
1134 const struct rtable *rt = skb_rtable(skb);
1135
1136 if (!rt)
1137 goto tx_err_link_failure;
1138
1139 if (rt->rt_gw_family == AF_INET6)
1140 memcpy(&fl6->daddr, &rt->rt_gw6, sizeof(fl6->daddr));
1141 }
1142 } else if (t->parms.proto != 0 && !(t->parms.flags &
1143 (IP6_TNL_F_USE_ORIG_TCLASS |
1144 IP6_TNL_F_USE_ORIG_FWMARK))) {
1145 /* enable the cache only if neither the outer protocol nor the
1146 * routing decision depends on the current inner header value
1147 */
1148 use_cache = true;
1149 }
1150
1151 if (use_cache)
1152 dst = dst_cache_get(&t->dst_cache);
1153
1154 if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
1155 goto tx_err_link_failure;
1156
1157 if (!dst) {
1158 route_lookup:
1159 /* add dsfield to flowlabel for route lookup */
1160 fl6->flowlabel = ip6_make_flowinfo(dsfield, fl6->flowlabel);
1161
1162 dst = ip6_route_output(net, NULL, fl6);
1163
1164 if (dst->error)
1165 goto tx_err_link_failure;
1166 dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0);
1167 if (IS_ERR(dst)) {
1168 err = PTR_ERR(dst);
1169 dst = NULL;
1170 goto tx_err_link_failure;
1171 }
1172 if (t->parms.collect_md && ipv6_addr_any(&fl6->saddr) &&
1173 ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
1174 &fl6->daddr, 0, &fl6->saddr))
1175 goto tx_err_link_failure;
1176 ndst = dst;
1177 }
1178
1179 tdev = dst->dev;
1180
1181 if (tdev == dev) {
1182 DEV_STATS_INC(dev, collisions);
1183 net_warn_ratelimited("%s: Local routing loop detected!\n",
1184 t->parms.name);
1185 goto tx_err_dst_release;
1186 }
1187 mtu = dst_mtu(dst) - eth_hlen - psh_hlen - t->tun_hlen;
1188 if (encap_limit >= 0) {
1189 max_headroom += 8;
1190 mtu -= 8;
1191 }
1192 mtu = max(mtu, skb->protocol == htons(ETH_P_IPV6) ?
1193 IPV6_MIN_MTU : IPV4_MIN_MTU);
1194
1195 skb_dst_update_pmtu_no_confirm(skb, mtu);
1196 if (skb->len - t->tun_hlen - eth_hlen > mtu && !skb_is_gso(skb)) {
1197 *pmtu = mtu;
1198 err = -EMSGSIZE;
1199 goto tx_err_dst_release;
1200 }
1201
1202 if (t->err_count > 0) {
1203 if (time_before(jiffies,
1204 t->err_time + IP6TUNNEL_ERR_TIMEO)) {
1205 t->err_count--;
1206
1207 dst_link_failure(skb);
1208 } else {
1209 t->err_count = 0;
1210 }
1211 }
1212
1213 skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
1214
1215 /*
1216 * Okay, now see if we can stuff it in the buffer as-is.
1217 */
1218 max_headroom += LL_RESERVED_SPACE(tdev);
1219
1220 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
1221 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
1222 struct sk_buff *new_skb;
1223
1224 new_skb = skb_realloc_headroom(skb, max_headroom);
1225 if (!new_skb)
1226 goto tx_err_dst_release;
1227
1228 if (skb->sk)
1229 skb_set_owner_w(new_skb, skb->sk);
1230 consume_skb(skb);
1231 skb = new_skb;
1232 }
1233
1234 if (t->parms.collect_md) {
1235 if (t->encap.type != TUNNEL_ENCAP_NONE)
1236 goto tx_err_dst_release;
1237 } else {
1238 if (use_cache && ndst)
1239 dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
1240 }
1241 skb_dst_set(skb, dst);
1242
1243 if (hop_limit == 0) {
1244 if (payload_protocol == htons(ETH_P_IP))
1245 hop_limit = ip_hdr(skb)->ttl;
1246 else if (payload_protocol == htons(ETH_P_IPV6))
1247 hop_limit = ipv6_hdr(skb)->hop_limit;
1248 else
1249 hop_limit = ip6_dst_hoplimit(dst);
1250 }
1251
1252 /* Calculate max headroom for all the headers and adjust
1253 * needed_headroom if necessary.
1254 */
1255 max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr)
1256 + dst->header_len + t->hlen;
1257 if (max_headroom > READ_ONCE(dev->needed_headroom))
1258 WRITE_ONCE(dev->needed_headroom, max_headroom);
1259
1260 err = ip6_tnl_encap(skb, t, &proto, fl6);
1261 if (err)
1262 return err;
1263
1264 if (encap_limit >= 0) {
1265 init_tel_txopt(&opt, encap_limit);
1266 ipv6_push_frag_opts(skb, &opt.ops, &proto);
1267 }
1268
1269 skb_push(skb, sizeof(struct ipv6hdr));
1270 skb_reset_network_header(skb);
1271 ipv6h = ipv6_hdr(skb);
1272 ip6_flow_hdr(ipv6h, dsfield,
1273 ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
1274 ipv6h->hop_limit = hop_limit;
1275 ipv6h->nexthdr = proto;
1276 ipv6h->saddr = fl6->saddr;
1277 ipv6h->daddr = fl6->daddr;
1278 ip6tunnel_xmit(NULL, skb, dev);
1279 return 0;
1280 tx_err_link_failure:
1281 DEV_STATS_INC(dev, tx_carrier_errors);
1282 dst_link_failure(skb);
1283 tx_err_dst_release:
1284 dst_release(dst);
1285 return err;
1286 }
1287 EXPORT_SYMBOL(ip6_tnl_xmit);
1288
1289 static inline int
1290 ipxip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev,
1291 u8 protocol)
1292 {
1293 struct ip6_tnl *t = netdev_priv(dev);
1294 struct ipv6hdr *ipv6h;
1295 const struct iphdr *iph;
1296 int encap_limit = -1;
1297 __u16 offset;
1298 struct flowi6 fl6;
1299 __u8 dsfield, orig_dsfield;
1300 __u32 mtu;
1301 u8 tproto;
1302 int err;
1303
1304 tproto = READ_ONCE(t->parms.proto);
1305 if (tproto != protocol && tproto != 0)
1306 return -1;
1307
1308 if (t->parms.collect_md) {
1309 struct ip_tunnel_info *tun_info;
1310 const struct ip_tunnel_key *key;
1311
1312 tun_info = skb_tunnel_info(skb);
1313 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
1314 ip_tunnel_info_af(tun_info) != AF_INET6))
1315 return -1;
1316 key = &tun_info->key;
1317 memset(&fl6, 0, sizeof(fl6));
1318 fl6.flowi6_proto = protocol;
1319 fl6.saddr = key->u.ipv6.src;
1320 fl6.daddr = key->u.ipv6.dst;
1321 fl6.flowlabel = key->label;
1322 dsfield = key->tos;
1323 switch (protocol) {
1324 case IPPROTO_IPIP:
1325 iph = ip_hdr(skb);
1326 orig_dsfield = ipv4_get_dsfield(iph);
1327 break;
1328 case IPPROTO_IPV6:
1329 ipv6h = ipv6_hdr(skb);
1330 orig_dsfield = ipv6_get_dsfield(ipv6h);
1331 break;
1332 default:
1333 orig_dsfield = dsfield;
1334 break;
1335 }
1336 } else {
1337 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1338 encap_limit = t->parms.encap_limit;
1339 if (protocol == IPPROTO_IPV6) {
1340 offset = ip6_tnl_parse_tlv_enc_lim(skb,
1341 skb_network_header(skb));
1342 /* ip6_tnl_parse_tlv_enc_lim() might have
1343 * reallocated skb->head
1344 */
1345 if (offset > 0) {
1346 struct ipv6_tlv_tnl_enc_lim *tel;
1347
1348 tel = (void *)&skb_network_header(skb)[offset];
1349 if (tel->encap_limit == 0) {
1350 icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
1351 ICMPV6_HDR_FIELD, offset + 2);
1352 return -1;
1353 }
1354 encap_limit = tel->encap_limit - 1;
1355 }
1356 }
1357
1358 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1359 fl6.flowi6_proto = protocol;
1360
1361 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
1362 fl6.flowi6_mark = skb->mark;
1363 else
1364 fl6.flowi6_mark = t->parms.fwmark;
1365 switch (protocol) {
1366 case IPPROTO_IPIP:
1367 iph = ip_hdr(skb);
1368 orig_dsfield = ipv4_get_dsfield(iph);
1369 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1370 dsfield = orig_dsfield;
1371 else
1372 dsfield = ip6_tclass(t->parms.flowinfo);
1373 break;
1374 case IPPROTO_IPV6:
1375 ipv6h = ipv6_hdr(skb);
1376 orig_dsfield = ipv6_get_dsfield(ipv6h);
1377 if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
1378 dsfield = orig_dsfield;
1379 else
1380 dsfield = ip6_tclass(t->parms.flowinfo);
1381 if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
1382 fl6.flowlabel |= ip6_flowlabel(ipv6h);
1383 break;
1384 default:
1385 orig_dsfield = dsfield = ip6_tclass(t->parms.flowinfo);
1386 break;
1387 }
1388 }
1389
1390 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
1391 dsfield = INET_ECN_encapsulate(dsfield, orig_dsfield);
1392
1393 if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
1394 return -1;
1395
1396 skb_set_inner_ipproto(skb, protocol);
1397
1398 err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1399 protocol);
1400 if (err != 0) {
1401 /* XXX: send ICMP error even if DF is not set. */
1402 if (err == -EMSGSIZE)
1403 switch (protocol) {
1404 case IPPROTO_IPIP:
1405 icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1406 ICMP_FRAG_NEEDED, htonl(mtu));
1407 break;
1408 case IPPROTO_IPV6:
1409 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1410 break;
1411 default:
1412 break;
1413 }
1414 return -1;
1415 }
1416
1417 return 0;
1418 }
1419
1420 static netdev_tx_t
1421 ip6_tnl_start_xmit(struct sk_buff *skb, struct net_device *dev)
1422 {
1423 struct ip6_tnl *t = netdev_priv(dev);
1424 u8 ipproto;
1425 int ret;
1426
1427 if (!pskb_inet_may_pull(skb))
1428 goto tx_err;
1429
1430 switch (skb->protocol) {
1431 case htons(ETH_P_IP):
1432 ipproto = IPPROTO_IPIP;
1433 break;
1434 case htons(ETH_P_IPV6):
1435 if (ip6_tnl_addr_conflict(t, ipv6_hdr(skb)))
1436 goto tx_err;
1437 ipproto = IPPROTO_IPV6;
1438 break;
1439 case htons(ETH_P_MPLS_UC):
1440 ipproto = IPPROTO_MPLS;
1441 break;
1442 default:
1443 goto tx_err;
1444 }
1445
1446 ret = ipxip6_tnl_xmit(skb, dev, ipproto);
1447 if (ret < 0)
1448 goto tx_err;
1449
1450 return NETDEV_TX_OK;
1451
1452 tx_err:
1453 DEV_STATS_INC(dev, tx_errors);
1454 DEV_STATS_INC(dev, tx_dropped);
1455 kfree_skb(skb);
1456 return NETDEV_TX_OK;
1457 }
1458
1459 static void ip6_tnl_link_config(struct ip6_tnl *t)
1460 {
1461 struct net_device *dev = t->dev;
1462 struct net_device *tdev = NULL;
1463 struct __ip6_tnl_parm *p = &t->parms;
1464 struct flowi6 *fl6 = &t->fl.u.ip6;
1465 int t_hlen;
1466 int mtu;
1467
1468 __dev_addr_set(dev, &p->laddr, sizeof(struct in6_addr));
1469 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1470
1471 /* Set up flowi template */
1472 fl6->saddr = p->laddr;
1473 fl6->daddr = p->raddr;
1474 fl6->flowi6_oif = p->link;
1475 fl6->flowlabel = 0;
1476
1477 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1478 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1479 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1480 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1481
1482 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1483 p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1484
1485 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
1486 dev->flags |= IFF_POINTOPOINT;
1487 else
1488 dev->flags &= ~IFF_POINTOPOINT;
1489
1490 t->tun_hlen = 0;
1491 t->hlen = t->encap_hlen + t->tun_hlen;
1492 t_hlen = t->hlen + sizeof(struct ipv6hdr);
1493
1494 if (p->flags & IP6_TNL_F_CAP_XMIT) {
1495 int strict = (ipv6_addr_type(&p->raddr) &
1496 (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1497
1498 struct rt6_info *rt = rt6_lookup(t->net,
1499 &p->raddr, &p->laddr,
1500 p->link, NULL, strict);
1501 if (rt) {
1502 tdev = rt->dst.dev;
1503 ip6_rt_put(rt);
1504 }
1505
1506 if (!tdev && p->link)
1507 tdev = __dev_get_by_index(t->net, p->link);
1508
1509 if (tdev) {
1510 dev->needed_headroom = tdev->hard_header_len +
1511 tdev->needed_headroom + t_hlen;
1512 mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU);
1513
1514 mtu = mtu - t_hlen;
1515 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1516 mtu -= 8;
1517
1518 if (mtu < IPV6_MIN_MTU)
1519 mtu = IPV6_MIN_MTU;
1520 WRITE_ONCE(dev->mtu, mtu);
1521 }
1522 }
1523 }
1524
1525 /**
1526 * ip6_tnl_change - update the tunnel parameters
1527 * @t: tunnel to be changed
1528 * @p: tunnel configuration parameters
1529 *
1530 * Description:
1531 * ip6_tnl_change() updates the tunnel parameters
1532 **/
1533
1534 static void
1535 ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
1536 {
1537 t->parms.laddr = p->laddr;
1538 t->parms.raddr = p->raddr;
1539 t->parms.flags = p->flags;
1540 t->parms.hop_limit = p->hop_limit;
1541 t->parms.encap_limit = p->encap_limit;
1542 t->parms.flowinfo = p->flowinfo;
1543 t->parms.link = p->link;
1544 t->parms.proto = p->proto;
1545 t->parms.fwmark = p->fwmark;
1546 dst_cache_reset(&t->dst_cache);
1547 ip6_tnl_link_config(t);
1548 }
1549
1550 static void ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1551 {
1552 struct net *net = t->net;
1553 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1554
1555 ip6_tnl_unlink(ip6n, t);
1556 synchronize_net();
1557 ip6_tnl_change(t, p);
1558 ip6_tnl_link(ip6n, t);
1559 netdev_state_change(t->dev);
1560 }
1561
1562 static void ip6_tnl0_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
1563 {
1564 /* for default tnl0 device allow to change only the proto */
1565 t->parms.proto = p->proto;
1566 netdev_state_change(t->dev);
1567 }
1568
1569 static void
1570 ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u)
1571 {
1572 p->laddr = u->laddr;
1573 p->raddr = u->raddr;
1574 p->flags = u->flags;
1575 p->hop_limit = u->hop_limit;
1576 p->encap_limit = u->encap_limit;
1577 p->flowinfo = u->flowinfo;
1578 p->link = u->link;
1579 p->proto = u->proto;
1580 memcpy(p->name, u->name, sizeof(u->name));
1581 }
1582
1583 static void
1584 ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p)
1585 {
1586 u->laddr = p->laddr;
1587 u->raddr = p->raddr;
1588 u->flags = p->flags;
1589 u->hop_limit = p->hop_limit;
1590 u->encap_limit = p->encap_limit;
1591 u->flowinfo = p->flowinfo;
1592 u->link = p->link;
1593 u->proto = p->proto;
1594 memcpy(u->name, p->name, sizeof(u->name));
1595 }
1596
1597 /**
1598 * ip6_tnl_siocdevprivate - configure ipv6 tunnels from userspace
1599 * @dev: virtual device associated with tunnel
1600 * @ifr: unused
1601 * @data: parameters passed from userspace
1602 * @cmd: command to be performed
1603 *
1604 * Description:
1605 * ip6_tnl_ioctl() is used for managing IPv6 tunnels
1606 * from userspace.
1607 *
1608 * The possible commands are the following:
1609 * %SIOCGETTUNNEL: get tunnel parameters for device
1610 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
1611 * %SIOCCHGTUNNEL: change tunnel parameters to those given
1612 * %SIOCDELTUNNEL: delete tunnel
1613 *
1614 * The fallback device "ip6tnl0", created during module
1615 * initialization, can be used for creating other tunnel devices.
1616 *
1617 * Return:
1618 * 0 on success,
1619 * %-EFAULT if unable to copy data to or from userspace,
1620 * %-EPERM if current process hasn't %CAP_NET_ADMIN set
1621 * %-EINVAL if passed tunnel parameters are invalid,
1622 * %-EEXIST if changing a tunnel's parameters would cause a conflict
1623 * %-ENODEV if attempting to change or delete a nonexisting device
1624 **/
1625
1626 static int
1627 ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
1628 void __user *data, int cmd)
1629 {
1630 int err = 0;
1631 struct ip6_tnl_parm p;
1632 struct __ip6_tnl_parm p1;
1633 struct ip6_tnl *t = netdev_priv(dev);
1634 struct net *net = t->net;
1635 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1636
1637 memset(&p1, 0, sizeof(p1));
1638
1639 switch (cmd) {
1640 case SIOCGETTUNNEL:
1641 if (dev == ip6n->fb_tnl_dev) {
1642 if (copy_from_user(&p, data, sizeof(p))) {
1643 err = -EFAULT;
1644 break;
1645 }
1646 ip6_tnl_parm_from_user(&p1, &p);
1647 t = ip6_tnl_locate(net, &p1, 0);
1648 if (IS_ERR(t))
1649 t = netdev_priv(dev);
1650 } else {
1651 memset(&p, 0, sizeof(p));
1652 }
1653 ip6_tnl_parm_to_user(&p, &t->parms);
1654 if (copy_to_user(data, &p, sizeof(p)))
1655 err = -EFAULT;
1656 break;
1657 case SIOCADDTUNNEL:
1658 case SIOCCHGTUNNEL:
1659 err = -EPERM;
1660 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1661 break;
1662 err = -EFAULT;
1663 if (copy_from_user(&p, data, sizeof(p)))
1664 break;
1665 err = -EINVAL;
1666 if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
1667 p.proto != 0)
1668 break;
1669 ip6_tnl_parm_from_user(&p1, &p);
1670 t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL);
1671 if (cmd == SIOCCHGTUNNEL) {
1672 if (!IS_ERR(t)) {
1673 if (t->dev != dev) {
1674 err = -EEXIST;
1675 break;
1676 }
1677 } else
1678 t = netdev_priv(dev);
1679 if (dev == ip6n->fb_tnl_dev)
1680 ip6_tnl0_update(t, &p1);
1681 else
1682 ip6_tnl_update(t, &p1);
1683 }
1684 if (!IS_ERR(t)) {
1685 err = 0;
1686 ip6_tnl_parm_to_user(&p, &t->parms);
1687 if (copy_to_user(data, &p, sizeof(p)))
1688 err = -EFAULT;
1689
1690 } else {
1691 err = PTR_ERR(t);
1692 }
1693 break;
1694 case SIOCDELTUNNEL:
1695 err = -EPERM;
1696 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1697 break;
1698
1699 if (dev == ip6n->fb_tnl_dev) {
1700 err = -EFAULT;
1701 if (copy_from_user(&p, data, sizeof(p)))
1702 break;
1703 err = -ENOENT;
1704 ip6_tnl_parm_from_user(&p1, &p);
1705 t = ip6_tnl_locate(net, &p1, 0);
1706 if (IS_ERR(t))
1707 break;
1708 err = -EPERM;
1709 if (t->dev == ip6n->fb_tnl_dev)
1710 break;
1711 dev = t->dev;
1712 }
1713 err = 0;
1714 unregister_netdevice(dev);
1715 break;
1716 default:
1717 err = -EINVAL;
1718 }
1719 return err;
1720 }
1721
1722 /**
1723 * ip6_tnl_change_mtu - change mtu manually for tunnel device
1724 * @dev: virtual device associated with tunnel
1725 * @new_mtu: the new mtu
1726 *
1727 * Return:
1728 * 0 on success,
1729 * %-EINVAL if mtu too small
1730 **/
1731
1732 int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1733 {
1734 struct ip6_tnl *tnl = netdev_priv(dev);
1735 int t_hlen;
1736
1737 t_hlen = tnl->hlen + sizeof(struct ipv6hdr);
1738 if (tnl->parms.proto == IPPROTO_IPV6) {
1739 if (new_mtu < IPV6_MIN_MTU)
1740 return -EINVAL;
1741 } else {
1742 if (new_mtu < ETH_MIN_MTU)
1743 return -EINVAL;
1744 }
1745 if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {
1746 if (new_mtu > IP6_MAX_MTU - dev->hard_header_len - t_hlen)
1747 return -EINVAL;
1748 } else {
1749 if (new_mtu > IP_MAX_MTU - dev->hard_header_len - t_hlen)
1750 return -EINVAL;
1751 }
1752 WRITE_ONCE(dev->mtu, new_mtu);
1753 return 0;
1754 }
1755 EXPORT_SYMBOL(ip6_tnl_change_mtu);
1756
1757 int ip6_tnl_get_iflink(const struct net_device *dev)
1758 {
1759 struct ip6_tnl *t = netdev_priv(dev);
1760
1761 return READ_ONCE(t->parms.link);
1762 }
1763 EXPORT_SYMBOL(ip6_tnl_get_iflink);
1764
1765 int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops,
1766 unsigned int num)
1767 {
1768 if (num >= MAX_IPTUN_ENCAP_OPS)
1769 return -ERANGE;
1770
1771 return !cmpxchg((const struct ip6_tnl_encap_ops **)
1772 &ip6tun_encaps[num],
1773 NULL, ops) ? 0 : -1;
1774 }
1775 EXPORT_SYMBOL(ip6_tnl_encap_add_ops);
1776
1777 int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops,
1778 unsigned int num)
1779 {
1780 int ret;
1781
1782 if (num >= MAX_IPTUN_ENCAP_OPS)
1783 return -ERANGE;
1784
1785 ret = (cmpxchg((const struct ip6_tnl_encap_ops **)
1786 &ip6tun_encaps[num],
1787 ops, NULL) == ops) ? 0 : -1;
1788
1789 synchronize_net();
1790
1791 return ret;
1792 }
1793 EXPORT_SYMBOL(ip6_tnl_encap_del_ops);
1794
1795 int ip6_tnl_encap_setup(struct ip6_tnl *t,
1796 struct ip_tunnel_encap *ipencap)
1797 {
1798 int hlen;
1799
1800 memset(&t->encap, 0, sizeof(t->encap));
1801
1802 hlen = ip6_encap_hlen(ipencap);
1803 if (hlen < 0)
1804 return hlen;
1805
1806 t->encap.type = ipencap->type;
1807 t->encap.sport = ipencap->sport;
1808 t->encap.dport = ipencap->dport;
1809 t->encap.flags = ipencap->flags;
1810
1811 t->encap_hlen = hlen;
1812 t->hlen = t->encap_hlen + t->tun_hlen;
1813
1814 return 0;
1815 }
1816 EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup);
1817
1818 static const struct net_device_ops ip6_tnl_netdev_ops = {
1819 .ndo_init = ip6_tnl_dev_init,
1820 .ndo_uninit = ip6_tnl_dev_uninit,
1821 .ndo_start_xmit = ip6_tnl_start_xmit,
1822 .ndo_siocdevprivate = ip6_tnl_siocdevprivate,
1823 .ndo_change_mtu = ip6_tnl_change_mtu,
1824 .ndo_get_stats64 = dev_get_tstats64,
1825 .ndo_get_iflink = ip6_tnl_get_iflink,
1826 };
1827
1828 #define IPXIPX_FEATURES (NETIF_F_SG | \
1829 NETIF_F_FRAGLIST | \
1830 NETIF_F_HIGHDMA | \
1831 NETIF_F_GSO_SOFTWARE | \
1832 NETIF_F_HW_CSUM)
1833
1834 /**
1835 * ip6_tnl_dev_setup - setup virtual tunnel device
1836 * @dev: virtual device associated with tunnel
1837 *
1838 * Description:
1839 * Initialize function pointers and device parameters
1840 **/
1841
1842 static void ip6_tnl_dev_setup(struct net_device *dev)
1843 {
1844 dev->netdev_ops = &ip6_tnl_netdev_ops;
1845 dev->header_ops = &ip_tunnel_header_ops;
1846 dev->needs_free_netdev = true;
1847 dev->priv_destructor = ip6_dev_free;
1848
1849 dev->type = ARPHRD_TUNNEL6;
1850 dev->flags |= IFF_NOARP;
1851 dev->addr_len = sizeof(struct in6_addr);
1852 dev->features |= NETIF_F_LLTX;
1853 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1854 netif_keep_dst(dev);
1855
1856 dev->features |= IPXIPX_FEATURES;
1857 dev->hw_features |= IPXIPX_FEATURES;
1858
1859 /* This perm addr will be used as interface identifier by IPv6 */
1860 dev->addr_assign_type = NET_ADDR_RANDOM;
1861 eth_random_addr(dev->perm_addr);
1862 }
1863
1864
1865 /**
1866 * ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1867 * @dev: virtual device associated with tunnel
1868 **/
1869
1870 static inline int
1871 ip6_tnl_dev_init_gen(struct net_device *dev)
1872 {
1873 struct ip6_tnl *t = netdev_priv(dev);
1874 int ret;
1875 int t_hlen;
1876
1877 t->dev = dev;
1878 t->net = dev_net(dev);
1879
1880 ret = dst_cache_init(&t->dst_cache, GFP_KERNEL);
1881 if (ret)
1882 return ret;
1883
1884 ret = gro_cells_init(&t->gro_cells, dev);
1885 if (ret)
1886 goto destroy_dst;
1887
1888 t->tun_hlen = 0;
1889 t->hlen = t->encap_hlen + t->tun_hlen;
1890 t_hlen = t->hlen + sizeof(struct ipv6hdr);
1891
1892 dev->type = ARPHRD_TUNNEL6;
1893 dev->mtu = ETH_DATA_LEN - t_hlen;
1894 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1895 dev->mtu -= 8;
1896 dev->min_mtu = ETH_MIN_MTU;
1897 dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len - t_hlen;
1898
1899 netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
1900 netdev_lockdep_set_classes(dev);
1901 return 0;
1902
1903 destroy_dst:
1904 dst_cache_destroy(&t->dst_cache);
1905
1906 return ret;
1907 }
1908
1909 /**
1910 * ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1911 * @dev: virtual device associated with tunnel
1912 **/
1913
1914 static int ip6_tnl_dev_init(struct net_device *dev)
1915 {
1916 struct ip6_tnl *t = netdev_priv(dev);
1917 int err = ip6_tnl_dev_init_gen(dev);
1918
1919 if (err)
1920 return err;
1921 ip6_tnl_link_config(t);
1922 if (t->parms.collect_md)
1923 netif_keep_dst(dev);
1924 return 0;
1925 }
1926
1927 /**
1928 * ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1929 * @dev: fallback device
1930 *
1931 * Return: 0
1932 **/
1933
1934 static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
1935 {
1936 struct ip6_tnl *t = netdev_priv(dev);
1937 struct net *net = dev_net(dev);
1938 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
1939
1940 t->parms.proto = IPPROTO_IPV6;
1941
1942 rcu_assign_pointer(ip6n->tnls_wc[0], t);
1943 return 0;
1944 }
1945
1946 static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[],
1947 struct netlink_ext_ack *extack)
1948 {
1949 u8 proto;
1950
1951 if (!data || !data[IFLA_IPTUN_PROTO])
1952 return 0;
1953
1954 proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1955 if (proto != IPPROTO_IPV6 &&
1956 proto != IPPROTO_IPIP &&
1957 proto != 0)
1958 return -EINVAL;
1959
1960 return 0;
1961 }
1962
1963 static void ip6_tnl_netlink_parms(struct nlattr *data[],
1964 struct __ip6_tnl_parm *parms)
1965 {
1966 memset(parms, 0, sizeof(*parms));
1967
1968 if (!data)
1969 return;
1970
1971 if (data[IFLA_IPTUN_LINK])
1972 parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
1973
1974 if (data[IFLA_IPTUN_LOCAL])
1975 parms->laddr = nla_get_in6_addr(data[IFLA_IPTUN_LOCAL]);
1976
1977 if (data[IFLA_IPTUN_REMOTE])
1978 parms->raddr = nla_get_in6_addr(data[IFLA_IPTUN_REMOTE]);
1979
1980 if (data[IFLA_IPTUN_TTL])
1981 parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]);
1982
1983 if (data[IFLA_IPTUN_ENCAP_LIMIT])
1984 parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]);
1985
1986 if (data[IFLA_IPTUN_FLOWINFO])
1987 parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]);
1988
1989 if (data[IFLA_IPTUN_FLAGS])
1990 parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]);
1991
1992 if (data[IFLA_IPTUN_PROTO])
1993 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
1994
1995 if (data[IFLA_IPTUN_COLLECT_METADATA])
1996 parms->collect_md = true;
1997
1998 if (data[IFLA_IPTUN_FWMARK])
1999 parms->fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
2000 }
2001
2002 static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
2003 struct nlattr *tb[], struct nlattr *data[],
2004 struct netlink_ext_ack *extack)
2005 {
2006 struct net *net = dev_net(dev);
2007 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2008 struct ip_tunnel_encap ipencap;
2009 struct ip6_tnl *nt, *t;
2010 int err;
2011
2012 nt = netdev_priv(dev);
2013
2014 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
2015 err = ip6_tnl_encap_setup(nt, &ipencap);
2016 if (err < 0)
2017 return err;
2018 }
2019
2020 ip6_tnl_netlink_parms(data, &nt->parms);
2021
2022 if (nt->parms.collect_md) {
2023 if (rtnl_dereference(ip6n->collect_md_tun))
2024 return -EEXIST;
2025 } else {
2026 t = ip6_tnl_locate(net, &nt->parms, 0);
2027 if (!IS_ERR(t))
2028 return -EEXIST;
2029 }
2030
2031 err = ip6_tnl_create2(dev);
2032 if (!err && tb[IFLA_MTU])
2033 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
2034
2035 return err;
2036 }
2037
2038 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
2039 struct nlattr *data[],
2040 struct netlink_ext_ack *extack)
2041 {
2042 struct ip6_tnl *t = netdev_priv(dev);
2043 struct __ip6_tnl_parm p;
2044 struct net *net = t->net;
2045 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2046 struct ip_tunnel_encap ipencap;
2047
2048 if (dev == ip6n->fb_tnl_dev)
2049 return -EINVAL;
2050
2051 if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
2052 int err = ip6_tnl_encap_setup(t, &ipencap);
2053
2054 if (err < 0)
2055 return err;
2056 }
2057 ip6_tnl_netlink_parms(data, &p);
2058 if (p.collect_md)
2059 return -EINVAL;
2060
2061 t = ip6_tnl_locate(net, &p, 0);
2062 if (!IS_ERR(t)) {
2063 if (t->dev != dev)
2064 return -EEXIST;
2065 } else
2066 t = netdev_priv(dev);
2067
2068 ip6_tnl_update(t, &p);
2069 return 0;
2070 }
2071
2072 static void ip6_tnl_dellink(struct net_device *dev, struct list_head *head)
2073 {
2074 struct net *net = dev_net(dev);
2075 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2076
2077 if (dev != ip6n->fb_tnl_dev)
2078 unregister_netdevice_queue(dev, head);
2079 }
2080
2081 static size_t ip6_tnl_get_size(const struct net_device *dev)
2082 {
2083 return
2084 /* IFLA_IPTUN_LINK */
2085 nla_total_size(4) +
2086 /* IFLA_IPTUN_LOCAL */
2087 nla_total_size(sizeof(struct in6_addr)) +
2088 /* IFLA_IPTUN_REMOTE */
2089 nla_total_size(sizeof(struct in6_addr)) +
2090 /* IFLA_IPTUN_TTL */
2091 nla_total_size(1) +
2092 /* IFLA_IPTUN_ENCAP_LIMIT */
2093 nla_total_size(1) +
2094 /* IFLA_IPTUN_FLOWINFO */
2095 nla_total_size(4) +
2096 /* IFLA_IPTUN_FLAGS */
2097 nla_total_size(4) +
2098 /* IFLA_IPTUN_PROTO */
2099 nla_total_size(1) +
2100 /* IFLA_IPTUN_ENCAP_TYPE */
2101 nla_total_size(2) +
2102 /* IFLA_IPTUN_ENCAP_FLAGS */
2103 nla_total_size(2) +
2104 /* IFLA_IPTUN_ENCAP_SPORT */
2105 nla_total_size(2) +
2106 /* IFLA_IPTUN_ENCAP_DPORT */
2107 nla_total_size(2) +
2108 /* IFLA_IPTUN_COLLECT_METADATA */
2109 nla_total_size(0) +
2110 /* IFLA_IPTUN_FWMARK */
2111 nla_total_size(4) +
2112 0;
2113 }
2114
2115 static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
2116 {
2117 struct ip6_tnl *tunnel = netdev_priv(dev);
2118 struct __ip6_tnl_parm *parm = &tunnel->parms;
2119
2120 if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
2121 nla_put_in6_addr(skb, IFLA_IPTUN_LOCAL, &parm->laddr) ||
2122 nla_put_in6_addr(skb, IFLA_IPTUN_REMOTE, &parm->raddr) ||
2123 nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) ||
2124 nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
2125 nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
2126 nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
2127 nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) ||
2128 nla_put_u32(skb, IFLA_IPTUN_FWMARK, parm->fwmark))
2129 goto nla_put_failure;
2130
2131 if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) ||
2132 nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) ||
2133 nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) ||
2134 nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags))
2135 goto nla_put_failure;
2136
2137 if (parm->collect_md)
2138 if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
2139 goto nla_put_failure;
2140
2141 return 0;
2142
2143 nla_put_failure:
2144 return -EMSGSIZE;
2145 }
2146
2147 struct net *ip6_tnl_get_link_net(const struct net_device *dev)
2148 {
2149 struct ip6_tnl *tunnel = netdev_priv(dev);
2150
2151 return READ_ONCE(tunnel->net);
2152 }
2153 EXPORT_SYMBOL(ip6_tnl_get_link_net);
2154
2155 static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
2156 [IFLA_IPTUN_LINK] = { .type = NLA_U32 },
2157 [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) },
2158 [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) },
2159 [IFLA_IPTUN_TTL] = { .type = NLA_U8 },
2160 [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 },
2161 [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 },
2162 [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 },
2163 [IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
2164 [IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 },
2165 [IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
2166 [IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
2167 [IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
2168 [IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG },
2169 [IFLA_IPTUN_FWMARK] = { .type = NLA_U32 },
2170 };
2171
2172 static struct rtnl_link_ops ip6_link_ops __read_mostly = {
2173 .kind = "ip6tnl",
2174 .maxtype = IFLA_IPTUN_MAX,
2175 .policy = ip6_tnl_policy,
2176 .priv_size = sizeof(struct ip6_tnl),
2177 .setup = ip6_tnl_dev_setup,
2178 .validate = ip6_tnl_validate,
2179 .newlink = ip6_tnl_newlink,
2180 .changelink = ip6_tnl_changelink,
2181 .dellink = ip6_tnl_dellink,
2182 .get_size = ip6_tnl_get_size,
2183 .fill_info = ip6_tnl_fill_info,
2184 .get_link_net = ip6_tnl_get_link_net,
2185 };
2186
2187 static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
2188 .handler = ip4ip6_rcv,
2189 .err_handler = ip4ip6_err,
2190 .priority = 1,
2191 };
2192
2193 static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
2194 .handler = ip6ip6_rcv,
2195 .err_handler = ip6ip6_err,
2196 .priority = 1,
2197 };
2198
2199 static struct xfrm6_tunnel mplsip6_handler __read_mostly = {
2200 .handler = mplsip6_rcv,
2201 .err_handler = mplsip6_err,
2202 .priority = 1,
2203 };
2204
2205 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list)
2206 {
2207 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2208 struct net_device *dev, *aux;
2209 int h;
2210 struct ip6_tnl *t;
2211
2212 for_each_netdev_safe(net, dev, aux)
2213 if (dev->rtnl_link_ops == &ip6_link_ops)
2214 unregister_netdevice_queue(dev, list);
2215
2216 for (h = 0; h < IP6_TUNNEL_HASH_SIZE; h++) {
2217 t = rtnl_dereference(ip6n->tnls_r_l[h]);
2218 while (t) {
2219 /* If dev is in the same netns, it has already
2220 * been added to the list by the previous loop.
2221 */
2222 if (!net_eq(dev_net(t->dev), net))
2223 unregister_netdevice_queue(t->dev, list);
2224 t = rtnl_dereference(t->next);
2225 }
2226 }
2227
2228 t = rtnl_dereference(ip6n->tnls_wc[0]);
2229 while (t) {
2230 /* If dev is in the same netns, it has already
2231 * been added to the list by the previous loop.
2232 */
2233 if (!net_eq(dev_net(t->dev), net))
2234 unregister_netdevice_queue(t->dev, list);
2235 t = rtnl_dereference(t->next);
2236 }
2237 }
2238
2239 static int __net_init ip6_tnl_init_net(struct net *net)
2240 {
2241 struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
2242 struct ip6_tnl *t = NULL;
2243 int err;
2244
2245 ip6n->tnls[0] = ip6n->tnls_wc;
2246 ip6n->tnls[1] = ip6n->tnls_r_l;
2247
2248 if (!net_has_fallback_tunnels(net))
2249 return 0;
2250 err = -ENOMEM;
2251 ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
2252 NET_NAME_UNKNOWN, ip6_tnl_dev_setup);
2253
2254 if (!ip6n->fb_tnl_dev)
2255 goto err_alloc_dev;
2256 dev_net_set(ip6n->fb_tnl_dev, net);
2257 ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops;
2258 /* FB netdevice is special: we have one, and only one per netns.
2259 * Allowing to move it to another netns is clearly unsafe.
2260 */
2261 ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL;
2262
2263 err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
2264 if (err < 0)
2265 goto err_register;
2266
2267 err = register_netdev(ip6n->fb_tnl_dev);
2268 if (err < 0)
2269 goto err_register;
2270
2271 t = netdev_priv(ip6n->fb_tnl_dev);
2272
2273 strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
2274 return 0;
2275
2276 err_register:
2277 free_netdev(ip6n->fb_tnl_dev);
2278 err_alloc_dev:
2279 return err;
2280 }
2281
2282 static void __net_exit ip6_tnl_exit_batch_rtnl(struct list_head *net_list,
2283 struct list_head *dev_to_kill)
2284 {
2285 struct net *net;
2286
2287 ASSERT_RTNL();
2288 list_for_each_entry(net, net_list, exit_list)
2289 ip6_tnl_destroy_tunnels(net, dev_to_kill);
2290 }
2291
2292 static struct pernet_operations ip6_tnl_net_ops = {
2293 .init = ip6_tnl_init_net,
2294 .exit_batch_rtnl = ip6_tnl_exit_batch_rtnl,
2295 .id = &ip6_tnl_net_id,
2296 .size = sizeof(struct ip6_tnl_net),
2297 };
2298
2299 /**
2300 * ip6_tunnel_init - register protocol and reserve needed resources
2301 *
2302 * Return: 0 on success
2303 **/
2304
2305 static int __init ip6_tunnel_init(void)
2306 {
2307 int err;
2308
2309 if (!ipv6_mod_enabled())
2310 return -EOPNOTSUPP;
2311
2312 err = register_pernet_device(&ip6_tnl_net_ops);
2313 if (err < 0)
2314 goto out_pernet;
2315
2316 err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET);
2317 if (err < 0) {
2318 pr_err("%s: can't register ip4ip6\n", __func__);
2319 goto out_ip4ip6;
2320 }
2321
2322 err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6);
2323 if (err < 0) {
2324 pr_err("%s: can't register ip6ip6\n", __func__);
2325 goto out_ip6ip6;
2326 }
2327
2328 if (ip6_tnl_mpls_supported()) {
2329 err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS);
2330 if (err < 0) {
2331 pr_err("%s: can't register mplsip6\n", __func__);
2332 goto out_mplsip6;
2333 }
2334 }
2335
2336 err = rtnl_link_register(&ip6_link_ops);
2337 if (err < 0)
2338 goto rtnl_link_failed;
2339
2340 return 0;
2341
2342 rtnl_link_failed:
2343 if (ip6_tnl_mpls_supported())
2344 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS);
2345 out_mplsip6:
2346 xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
2347 out_ip6ip6:
2348 xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
2349 out_ip4ip6:
2350 unregister_pernet_device(&ip6_tnl_net_ops);
2351 out_pernet:
2352 return err;
2353 }
2354
2355 /**
2356 * ip6_tunnel_cleanup - free resources and unregister protocol
2357 **/
2358
2359 static void __exit ip6_tunnel_cleanup(void)
2360 {
2361 rtnl_link_unregister(&ip6_link_ops);
2362 if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET))
2363 pr_info("%s: can't deregister ip4ip6\n", __func__);
2364
2365 if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
2366 pr_info("%s: can't deregister ip6ip6\n", __func__);
2367
2368 if (ip6_tnl_mpls_supported() &&
2369 xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS))
2370 pr_info("%s: can't deregister mplsip6\n", __func__);
2371 unregister_pernet_device(&ip6_tnl_net_ops);
2372 }
2373
2374 module_init(ip6_tunnel_init);
2375 module_exit(ip6_tunnel_cleanup);
2376
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