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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2013 Nicira, Inc.
4 */
5
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8#include <linux/capability.h>
9#include <linux/module.h>
10#include <linux/types.h>
11#include <linux/kernel.h>
12#include <linux/slab.h>
13#include <linux/uaccess.h>
14#include <linux/skbuff.h>
15#include <linux/netdevice.h>
16#include <linux/in.h>
17#include <linux/tcp.h>
18#include <linux/udp.h>
19#include <linux/if_arp.h>
20#include <linux/init.h>
21#include <linux/in6.h>
22#include <linux/inetdevice.h>
23#include <linux/igmp.h>
24#include <linux/netfilter_ipv4.h>
25#include <linux/etherdevice.h>
26#include <linux/if_ether.h>
27#include <linux/if_vlan.h>
28#include <linux/rculist.h>
29#include <linux/err.h>
30
31#include <net/sock.h>
32#include <net/ip.h>
33#include <net/icmp.h>
34#include <net/protocol.h>
35#include <net/ip_tunnels.h>
36#include <net/arp.h>
37#include <net/checksum.h>
38#include <net/dsfield.h>
39#include <net/inet_ecn.h>
40#include <net/xfrm.h>
41#include <net/net_namespace.h>
42#include <net/netns/generic.h>
43#include <net/rtnetlink.h>
44#include <net/udp.h>
45#include <net/dst_metadata.h>
46#include <net/inet_dscp.h>
47
48#if IS_ENABLED(CONFIG_IPV6)
49#include <net/ipv6.h>
50#include <net/ip6_fib.h>
51#include <net/ip6_route.h>
52#endif
53
54static unsigned int ip_tunnel_hash(__be32 key, __be32 remote)
55{
56 return hash_32((__force u32)key ^ (__force u32)remote,
57 IP_TNL_HASH_BITS);
58}
59
60static bool ip_tunnel_key_match(const struct ip_tunnel_parm_kern *p,
61 const unsigned long *flags, __be32 key)
62{
63 if (!test_bit(IP_TUNNEL_KEY_BIT, flags))
64 return !test_bit(IP_TUNNEL_KEY_BIT, p->i_flags);
65
66 return test_bit(IP_TUNNEL_KEY_BIT, p->i_flags) && p->i_key == key;
67}
68
69/* Fallback tunnel: no source, no destination, no key, no options
70
71 Tunnel hash table:
72 We require exact key match i.e. if a key is present in packet
73 it will match only tunnel with the same key; if it is not present,
74 it will match only keyless tunnel.
75
76 All keysless packets, if not matched configured keyless tunnels
77 will match fallback tunnel.
78 Given src, dst and key, find appropriate for input tunnel.
79*/
80struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
81 int link, const unsigned long *flags,
82 __be32 remote, __be32 local,
83 __be32 key)
84{
85 struct ip_tunnel *t, *cand = NULL;
86 struct hlist_head *head;
87 struct net_device *ndev;
88 unsigned int hash;
89
90 hash = ip_tunnel_hash(key, remote);
91 head = &itn->tunnels[hash];
92
93 hlist_for_each_entry_rcu(t, head, hash_node) {
94 if (local != t->parms.iph.saddr ||
95 remote != t->parms.iph.daddr ||
96 !(t->dev->flags & IFF_UP))
97 continue;
98
99 if (!ip_tunnel_key_match(&t->parms, flags, key))
100 continue;
101
102 if (READ_ONCE(t->parms.link) == link)
103 return t;
104 cand = t;
105 }
106
107 hlist_for_each_entry_rcu(t, head, hash_node) {
108 if (remote != t->parms.iph.daddr ||
109 t->parms.iph.saddr != 0 ||
110 !(t->dev->flags & IFF_UP))
111 continue;
112
113 if (!ip_tunnel_key_match(&t->parms, flags, key))
114 continue;
115
116 if (READ_ONCE(t->parms.link) == link)
117 return t;
118 if (!cand)
119 cand = t;
120 }
121
122 hash = ip_tunnel_hash(key, 0);
123 head = &itn->tunnels[hash];
124
125 hlist_for_each_entry_rcu(t, head, hash_node) {
126 if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) &&
127 (local != t->parms.iph.daddr || !ipv4_is_multicast(local)))
128 continue;
129
130 if (!(t->dev->flags & IFF_UP))
131 continue;
132
133 if (!ip_tunnel_key_match(&t->parms, flags, key))
134 continue;
135
136 if (READ_ONCE(t->parms.link) == link)
137 return t;
138 if (!cand)
139 cand = t;
140 }
141
142 hlist_for_each_entry_rcu(t, head, hash_node) {
143 if ((!test_bit(IP_TUNNEL_NO_KEY_BIT, flags) &&
144 t->parms.i_key != key) ||
145 t->parms.iph.saddr != 0 ||
146 t->parms.iph.daddr != 0 ||
147 !(t->dev->flags & IFF_UP))
148 continue;
149
150 if (READ_ONCE(t->parms.link) == link)
151 return t;
152 if (!cand)
153 cand = t;
154 }
155
156 if (cand)
157 return cand;
158
159 t = rcu_dereference(itn->collect_md_tun);
160 if (t && t->dev->flags & IFF_UP)
161 return t;
162
163 ndev = READ_ONCE(itn->fb_tunnel_dev);
164 if (ndev && ndev->flags & IFF_UP)
165 return netdev_priv(ndev);
166
167 return NULL;
168}
169EXPORT_SYMBOL_GPL(ip_tunnel_lookup);
170
171static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn,
172 struct ip_tunnel_parm_kern *parms)
173{
174 unsigned int h;
175 __be32 remote;
176 __be32 i_key = parms->i_key;
177
178 if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr))
179 remote = parms->iph.daddr;
180 else
181 remote = 0;
182
183 if (!test_bit(IP_TUNNEL_KEY_BIT, parms->i_flags) &&
184 test_bit(IP_TUNNEL_VTI_BIT, parms->i_flags))
185 i_key = 0;
186
187 h = ip_tunnel_hash(i_key, remote);
188 return &itn->tunnels[h];
189}
190
191static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t)
192{
193 struct hlist_head *head = ip_bucket(itn, &t->parms);
194
195 if (t->collect_md)
196 rcu_assign_pointer(itn->collect_md_tun, t);
197 hlist_add_head_rcu(&t->hash_node, head);
198}
199
200static void ip_tunnel_del(struct ip_tunnel_net *itn, struct ip_tunnel *t)
201{
202 if (t->collect_md)
203 rcu_assign_pointer(itn->collect_md_tun, NULL);
204 hlist_del_init_rcu(&t->hash_node);
205}
206
207static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn,
208 struct ip_tunnel_parm_kern *parms,
209 int type)
210{
211 __be32 remote = parms->iph.daddr;
212 __be32 local = parms->iph.saddr;
213 IP_TUNNEL_DECLARE_FLAGS(flags);
214 __be32 key = parms->i_key;
215 int link = parms->link;
216 struct ip_tunnel *t = NULL;
217 struct hlist_head *head = ip_bucket(itn, parms);
218
219 ip_tunnel_flags_copy(flags, parms->i_flags);
220
221 hlist_for_each_entry_rcu(t, head, hash_node, lockdep_rtnl_is_held()) {
222 if (local == t->parms.iph.saddr &&
223 remote == t->parms.iph.daddr &&
224 link == READ_ONCE(t->parms.link) &&
225 type == t->dev->type &&
226 ip_tunnel_key_match(&t->parms, flags, key))
227 break;
228 }
229 return t;
230}
231
232static struct net_device *__ip_tunnel_create(struct net *net,
233 const struct rtnl_link_ops *ops,
234 struct ip_tunnel_parm_kern *parms)
235{
236 int err;
237 struct ip_tunnel *tunnel;
238 struct net_device *dev;
239 char name[IFNAMSIZ];
240
241 err = -E2BIG;
242 if (parms->name[0]) {
243 if (!dev_valid_name(parms->name))
244 goto failed;
245 strscpy(name, parms->name, IFNAMSIZ);
246 } else {
247 if (strlen(ops->kind) > (IFNAMSIZ - 3))
248 goto failed;
249 strcpy(name, ops->kind);
250 strcat(name, "%d");
251 }
252
253 ASSERT_RTNL();
254 dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup);
255 if (!dev) {
256 err = -ENOMEM;
257 goto failed;
258 }
259 dev_net_set(dev, net);
260
261 dev->rtnl_link_ops = ops;
262
263 tunnel = netdev_priv(dev);
264 tunnel->parms = *parms;
265 tunnel->net = net;
266
267 err = register_netdevice(dev);
268 if (err)
269 goto failed_free;
270
271 return dev;
272
273failed_free:
274 free_netdev(dev);
275failed:
276 return ERR_PTR(err);
277}
278
279static int ip_tunnel_bind_dev(struct net_device *dev)
280{
281 struct net_device *tdev = NULL;
282 struct ip_tunnel *tunnel = netdev_priv(dev);
283 const struct iphdr *iph;
284 int hlen = LL_MAX_HEADER;
285 int mtu = ETH_DATA_LEN;
286 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
287
288 iph = &tunnel->parms.iph;
289
290 /* Guess output device to choose reasonable mtu and needed_headroom */
291 if (iph->daddr) {
292 struct flowi4 fl4;
293 struct rtable *rt;
294
295 ip_tunnel_init_flow(&fl4, iph->protocol, iph->daddr,
296 iph->saddr, tunnel->parms.o_key,
297 iph->tos & INET_DSCP_MASK, tunnel->net,
298 tunnel->parms.link, tunnel->fwmark, 0, 0);
299 rt = ip_route_output_key(tunnel->net, &fl4);
300
301 if (!IS_ERR(rt)) {
302 tdev = rt->dst.dev;
303 ip_rt_put(rt);
304 }
305 if (dev->type != ARPHRD_ETHER)
306 dev->flags |= IFF_POINTOPOINT;
307
308 dst_cache_reset(&tunnel->dst_cache);
309 }
310
311 if (!tdev && tunnel->parms.link)
312 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
313
314 if (tdev) {
315 hlen = tdev->hard_header_len + tdev->needed_headroom;
316 mtu = min(tdev->mtu, IP_MAX_MTU);
317 }
318
319 dev->needed_headroom = t_hlen + hlen;
320 mtu -= t_hlen + (dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0);
321
322 if (mtu < IPV4_MIN_MTU)
323 mtu = IPV4_MIN_MTU;
324
325 return mtu;
326}
327
328static struct ip_tunnel *ip_tunnel_create(struct net *net,
329 struct ip_tunnel_net *itn,
330 struct ip_tunnel_parm_kern *parms)
331{
332 struct ip_tunnel *nt;
333 struct net_device *dev;
334 int t_hlen;
335 int mtu;
336 int err;
337
338 dev = __ip_tunnel_create(net, itn->rtnl_link_ops, parms);
339 if (IS_ERR(dev))
340 return ERR_CAST(dev);
341
342 mtu = ip_tunnel_bind_dev(dev);
343 err = dev_set_mtu(dev, mtu);
344 if (err)
345 goto err_dev_set_mtu;
346
347 nt = netdev_priv(dev);
348 t_hlen = nt->hlen + sizeof(struct iphdr);
349 dev->min_mtu = ETH_MIN_MTU;
350 dev->max_mtu = IP_MAX_MTU - t_hlen;
351 if (dev->type == ARPHRD_ETHER)
352 dev->max_mtu -= dev->hard_header_len;
353
354 ip_tunnel_add(itn, nt);
355 return nt;
356
357err_dev_set_mtu:
358 unregister_netdevice(dev);
359 return ERR_PTR(err);
360}
361
362void ip_tunnel_md_udp_encap(struct sk_buff *skb, struct ip_tunnel_info *info)
363{
364 const struct iphdr *iph = ip_hdr(skb);
365 const struct udphdr *udph;
366
367 if (iph->protocol != IPPROTO_UDP)
368 return;
369
370 udph = (struct udphdr *)((__u8 *)iph + (iph->ihl << 2));
371 info->encap.sport = udph->source;
372 info->encap.dport = udph->dest;
373}
374EXPORT_SYMBOL(ip_tunnel_md_udp_encap);
375
376int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
377 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
378 bool log_ecn_error)
379{
380 const struct iphdr *iph = ip_hdr(skb);
381 int nh, err;
382
383#ifdef CONFIG_NET_IPGRE_BROADCAST
384 if (ipv4_is_multicast(iph->daddr)) {
385 DEV_STATS_INC(tunnel->dev, multicast);
386 skb->pkt_type = PACKET_BROADCAST;
387 }
388#endif
389
390 if (test_bit(IP_TUNNEL_CSUM_BIT, tunnel->parms.i_flags) !=
391 test_bit(IP_TUNNEL_CSUM_BIT, tpi->flags)) {
392 DEV_STATS_INC(tunnel->dev, rx_crc_errors);
393 DEV_STATS_INC(tunnel->dev, rx_errors);
394 goto drop;
395 }
396
397 if (test_bit(IP_TUNNEL_SEQ_BIT, tunnel->parms.i_flags)) {
398 if (!test_bit(IP_TUNNEL_SEQ_BIT, tpi->flags) ||
399 (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
400 DEV_STATS_INC(tunnel->dev, rx_fifo_errors);
401 DEV_STATS_INC(tunnel->dev, rx_errors);
402 goto drop;
403 }
404 tunnel->i_seqno = ntohl(tpi->seq) + 1;
405 }
406
407 /* Save offset of outer header relative to skb->head,
408 * because we are going to reset the network header to the inner header
409 * and might change skb->head.
410 */
411 nh = skb_network_header(skb) - skb->head;
412
413 skb_set_network_header(skb, (tunnel->dev->type == ARPHRD_ETHER) ? ETH_HLEN : 0);
414
415 if (!pskb_inet_may_pull(skb)) {
416 DEV_STATS_INC(tunnel->dev, rx_length_errors);
417 DEV_STATS_INC(tunnel->dev, rx_errors);
418 goto drop;
419 }
420 iph = (struct iphdr *)(skb->head + nh);
421
422 err = IP_ECN_decapsulate(iph, skb);
423 if (unlikely(err)) {
424 if (log_ecn_error)
425 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
426 &iph->saddr, iph->tos);
427 if (err > 1) {
428 DEV_STATS_INC(tunnel->dev, rx_frame_errors);
429 DEV_STATS_INC(tunnel->dev, rx_errors);
430 goto drop;
431 }
432 }
433
434 dev_sw_netstats_rx_add(tunnel->dev, skb->len);
435 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
436
437 if (tunnel->dev->type == ARPHRD_ETHER) {
438 skb->protocol = eth_type_trans(skb, tunnel->dev);
439 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
440 } else {
441 skb->dev = tunnel->dev;
442 }
443
444 if (tun_dst)
445 skb_dst_set(skb, (struct dst_entry *)tun_dst);
446
447 gro_cells_receive(&tunnel->gro_cells, skb);
448 return 0;
449
450drop:
451 if (tun_dst)
452 dst_release((struct dst_entry *)tun_dst);
453 kfree_skb(skb);
454 return 0;
455}
456EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
457
458int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops,
459 unsigned int num)
460{
461 if (num >= MAX_IPTUN_ENCAP_OPS)
462 return -ERANGE;
463
464 return !cmpxchg((const struct ip_tunnel_encap_ops **)
465 &iptun_encaps[num],
466 NULL, ops) ? 0 : -1;
467}
468EXPORT_SYMBOL(ip_tunnel_encap_add_ops);
469
470int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops,
471 unsigned int num)
472{
473 int ret;
474
475 if (num >= MAX_IPTUN_ENCAP_OPS)
476 return -ERANGE;
477
478 ret = (cmpxchg((const struct ip_tunnel_encap_ops **)
479 &iptun_encaps[num],
480 ops, NULL) == ops) ? 0 : -1;
481
482 synchronize_net();
483
484 return ret;
485}
486EXPORT_SYMBOL(ip_tunnel_encap_del_ops);
487
488int ip_tunnel_encap_setup(struct ip_tunnel *t,
489 struct ip_tunnel_encap *ipencap)
490{
491 int hlen;
492
493 memset(&t->encap, 0, sizeof(t->encap));
494
495 hlen = ip_encap_hlen(ipencap);
496 if (hlen < 0)
497 return hlen;
498
499 t->encap.type = ipencap->type;
500 t->encap.sport = ipencap->sport;
501 t->encap.dport = ipencap->dport;
502 t->encap.flags = ipencap->flags;
503
504 t->encap_hlen = hlen;
505 t->hlen = t->encap_hlen + t->tun_hlen;
506
507 return 0;
508}
509EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup);
510
511static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
512 struct rtable *rt, __be16 df,
513 const struct iphdr *inner_iph,
514 int tunnel_hlen, __be32 dst, bool md)
515{
516 struct ip_tunnel *tunnel = netdev_priv(dev);
517 int pkt_size;
518 int mtu;
519
520 tunnel_hlen = md ? tunnel_hlen : tunnel->hlen;
521 pkt_size = skb->len - tunnel_hlen;
522 pkt_size -= dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0;
523
524 if (df) {
525 mtu = dst_mtu(&rt->dst) - (sizeof(struct iphdr) + tunnel_hlen);
526 mtu -= dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0;
527 } else {
528 mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
529 }
530
531 if (skb_valid_dst(skb))
532 skb_dst_update_pmtu_no_confirm(skb, mtu);
533
534 if (skb->protocol == htons(ETH_P_IP)) {
535 if (!skb_is_gso(skb) &&
536 (inner_iph->frag_off & htons(IP_DF)) &&
537 mtu < pkt_size) {
538 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
539 return -E2BIG;
540 }
541 }
542#if IS_ENABLED(CONFIG_IPV6)
543 else if (skb->protocol == htons(ETH_P_IPV6)) {
544 struct rt6_info *rt6;
545 __be32 daddr;
546
547 rt6 = skb_valid_dst(skb) ? dst_rt6_info(skb_dst(skb)) :
548 NULL;
549 daddr = md ? dst : tunnel->parms.iph.daddr;
550
551 if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
552 mtu >= IPV6_MIN_MTU) {
553 if ((daddr && !ipv4_is_multicast(daddr)) ||
554 rt6->rt6i_dst.plen == 128) {
555 rt6->rt6i_flags |= RTF_MODIFIED;
556 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
557 }
558 }
559
560 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
561 mtu < pkt_size) {
562 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
563 return -E2BIG;
564 }
565 }
566#endif
567 return 0;
568}
569
570static void ip_tunnel_adj_headroom(struct net_device *dev, unsigned int headroom)
571{
572 /* we must cap headroom to some upperlimit, else pskb_expand_head
573 * will overflow header offsets in skb_headers_offset_update().
574 */
575 static const unsigned int max_allowed = 512;
576
577 if (headroom > max_allowed)
578 headroom = max_allowed;
579
580 if (headroom > READ_ONCE(dev->needed_headroom))
581 WRITE_ONCE(dev->needed_headroom, headroom);
582}
583
584void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
585 u8 proto, int tunnel_hlen)
586{
587 struct ip_tunnel *tunnel = netdev_priv(dev);
588 u32 headroom = sizeof(struct iphdr);
589 struct ip_tunnel_info *tun_info;
590 const struct ip_tunnel_key *key;
591 const struct iphdr *inner_iph;
592 struct rtable *rt = NULL;
593 struct flowi4 fl4;
594 __be16 df = 0;
595 u8 tos, ttl;
596 bool use_cache;
597
598 tun_info = skb_tunnel_info(skb);
599 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
600 ip_tunnel_info_af(tun_info) != AF_INET))
601 goto tx_error;
602 key = &tun_info->key;
603 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
604 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
605 tos = key->tos;
606 if (tos == 1) {
607 if (skb->protocol == htons(ETH_P_IP))
608 tos = inner_iph->tos;
609 else if (skb->protocol == htons(ETH_P_IPV6))
610 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
611 }
612 ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src,
613 tunnel_id_to_key32(key->tun_id),
614 tos & INET_DSCP_MASK, tunnel->net, 0, skb->mark,
615 skb_get_hash(skb), key->flow_flags);
616
617 if (!tunnel_hlen)
618 tunnel_hlen = ip_encap_hlen(&tun_info->encap);
619
620 if (ip_tunnel_encap(skb, &tun_info->encap, &proto, &fl4) < 0)
621 goto tx_error;
622
623 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
624 if (use_cache)
625 rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl4.saddr);
626 if (!rt) {
627 rt = ip_route_output_key(tunnel->net, &fl4);
628 if (IS_ERR(rt)) {
629 DEV_STATS_INC(dev, tx_carrier_errors);
630 goto tx_error;
631 }
632 if (use_cache)
633 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
634 fl4.saddr);
635 }
636 if (rt->dst.dev == dev) {
637 ip_rt_put(rt);
638 DEV_STATS_INC(dev, collisions);
639 goto tx_error;
640 }
641
642 if (test_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, key->tun_flags))
643 df = htons(IP_DF);
644 if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, tunnel_hlen,
645 key->u.ipv4.dst, true)) {
646 ip_rt_put(rt);
647 goto tx_error;
648 }
649
650 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
651 ttl = key->ttl;
652 if (ttl == 0) {
653 if (skb->protocol == htons(ETH_P_IP))
654 ttl = inner_iph->ttl;
655 else if (skb->protocol == htons(ETH_P_IPV6))
656 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
657 else
658 ttl = ip4_dst_hoplimit(&rt->dst);
659 }
660
661 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
662 if (skb_cow_head(skb, headroom)) {
663 ip_rt_put(rt);
664 goto tx_dropped;
665 }
666
667 ip_tunnel_adj_headroom(dev, headroom);
668
669 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl,
670 df, !net_eq(tunnel->net, dev_net(dev)));
671 return;
672tx_error:
673 DEV_STATS_INC(dev, tx_errors);
674 goto kfree;
675tx_dropped:
676 DEV_STATS_INC(dev, tx_dropped);
677kfree:
678 kfree_skb(skb);
679}
680EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
681
682void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
683 const struct iphdr *tnl_params, u8 protocol)
684{
685 struct ip_tunnel *tunnel = netdev_priv(dev);
686 struct ip_tunnel_info *tun_info = NULL;
687 const struct iphdr *inner_iph;
688 unsigned int max_headroom; /* The extra header space needed */
689 struct rtable *rt = NULL; /* Route to the other host */
690 __be16 payload_protocol;
691 bool use_cache = false;
692 struct flowi4 fl4;
693 bool md = false;
694 bool connected;
695 u8 tos, ttl;
696 __be32 dst;
697 __be16 df;
698
699 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
700 connected = (tunnel->parms.iph.daddr != 0);
701 payload_protocol = skb_protocol(skb, true);
702
703 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
704
705 dst = tnl_params->daddr;
706 if (dst == 0) {
707 /* NBMA tunnel */
708
709 if (!skb_dst(skb)) {
710 DEV_STATS_INC(dev, tx_fifo_errors);
711 goto tx_error;
712 }
713
714 tun_info = skb_tunnel_info(skb);
715 if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX) &&
716 ip_tunnel_info_af(tun_info) == AF_INET &&
717 tun_info->key.u.ipv4.dst) {
718 dst = tun_info->key.u.ipv4.dst;
719 md = true;
720 connected = true;
721 } else if (payload_protocol == htons(ETH_P_IP)) {
722 rt = skb_rtable(skb);
723 dst = rt_nexthop(rt, inner_iph->daddr);
724 }
725#if IS_ENABLED(CONFIG_IPV6)
726 else if (payload_protocol == htons(ETH_P_IPV6)) {
727 const struct in6_addr *addr6;
728 struct neighbour *neigh;
729 bool do_tx_error_icmp;
730 int addr_type;
731
732 neigh = dst_neigh_lookup(skb_dst(skb),
733 &ipv6_hdr(skb)->daddr);
734 if (!neigh)
735 goto tx_error;
736
737 addr6 = (const struct in6_addr *)&neigh->primary_key;
738 addr_type = ipv6_addr_type(addr6);
739
740 if (addr_type == IPV6_ADDR_ANY) {
741 addr6 = &ipv6_hdr(skb)->daddr;
742 addr_type = ipv6_addr_type(addr6);
743 }
744
745 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
746 do_tx_error_icmp = true;
747 else {
748 do_tx_error_icmp = false;
749 dst = addr6->s6_addr32[3];
750 }
751 neigh_release(neigh);
752 if (do_tx_error_icmp)
753 goto tx_error_icmp;
754 }
755#endif
756 else
757 goto tx_error;
758
759 if (!md)
760 connected = false;
761 }
762
763 tos = tnl_params->tos;
764 if (tos & 0x1) {
765 tos &= ~0x1;
766 if (payload_protocol == htons(ETH_P_IP)) {
767 tos = inner_iph->tos;
768 connected = false;
769 } else if (payload_protocol == htons(ETH_P_IPV6)) {
770 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
771 connected = false;
772 }
773 }
774
775 ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr,
776 tunnel->parms.o_key, tos & INET_DSCP_MASK,
777 tunnel->net, READ_ONCE(tunnel->parms.link),
778 tunnel->fwmark, skb_get_hash(skb), 0);
779
780 if (ip_tunnel_encap(skb, &tunnel->encap, &protocol, &fl4) < 0)
781 goto tx_error;
782
783 if (connected && md) {
784 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
785 if (use_cache)
786 rt = dst_cache_get_ip4(&tun_info->dst_cache,
787 &fl4.saddr);
788 } else {
789 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache,
790 &fl4.saddr) : NULL;
791 }
792
793 if (!rt) {
794 rt = ip_route_output_key(tunnel->net, &fl4);
795
796 if (IS_ERR(rt)) {
797 DEV_STATS_INC(dev, tx_carrier_errors);
798 goto tx_error;
799 }
800 if (use_cache)
801 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
802 fl4.saddr);
803 else if (!md && connected)
804 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst,
805 fl4.saddr);
806 }
807
808 if (rt->dst.dev == dev) {
809 ip_rt_put(rt);
810 DEV_STATS_INC(dev, collisions);
811 goto tx_error;
812 }
813
814 df = tnl_params->frag_off;
815 if (payload_protocol == htons(ETH_P_IP) && !tunnel->ignore_df)
816 df |= (inner_iph->frag_off & htons(IP_DF));
817
818 if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, 0, 0, false)) {
819 ip_rt_put(rt);
820 goto tx_error;
821 }
822
823 if (tunnel->err_count > 0) {
824 if (time_before(jiffies,
825 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
826 tunnel->err_count--;
827
828 dst_link_failure(skb);
829 } else
830 tunnel->err_count = 0;
831 }
832
833 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
834 ttl = tnl_params->ttl;
835 if (ttl == 0) {
836 if (payload_protocol == htons(ETH_P_IP))
837 ttl = inner_iph->ttl;
838#if IS_ENABLED(CONFIG_IPV6)
839 else if (payload_protocol == htons(ETH_P_IPV6))
840 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
841#endif
842 else
843 ttl = ip4_dst_hoplimit(&rt->dst);
844 }
845
846 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
847 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap);
848
849 if (skb_cow_head(skb, max_headroom)) {
850 ip_rt_put(rt);
851 DEV_STATS_INC(dev, tx_dropped);
852 kfree_skb(skb);
853 return;
854 }
855
856 ip_tunnel_adj_headroom(dev, max_headroom);
857
858 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
859 df, !net_eq(tunnel->net, dev_net(dev)));
860 return;
861
862#if IS_ENABLED(CONFIG_IPV6)
863tx_error_icmp:
864 dst_link_failure(skb);
865#endif
866tx_error:
867 DEV_STATS_INC(dev, tx_errors);
868 kfree_skb(skb);
869}
870EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
871
872static void ip_tunnel_update(struct ip_tunnel_net *itn,
873 struct ip_tunnel *t,
874 struct net_device *dev,
875 struct ip_tunnel_parm_kern *p,
876 bool set_mtu,
877 __u32 fwmark)
878{
879 ip_tunnel_del(itn, t);
880 t->parms.iph.saddr = p->iph.saddr;
881 t->parms.iph.daddr = p->iph.daddr;
882 t->parms.i_key = p->i_key;
883 t->parms.o_key = p->o_key;
884 if (dev->type != ARPHRD_ETHER) {
885 __dev_addr_set(dev, &p->iph.saddr, 4);
886 memcpy(dev->broadcast, &p->iph.daddr, 4);
887 }
888 ip_tunnel_add(itn, t);
889
890 t->parms.iph.ttl = p->iph.ttl;
891 t->parms.iph.tos = p->iph.tos;
892 t->parms.iph.frag_off = p->iph.frag_off;
893
894 if (t->parms.link != p->link || t->fwmark != fwmark) {
895 int mtu;
896
897 WRITE_ONCE(t->parms.link, p->link);
898 t->fwmark = fwmark;
899 mtu = ip_tunnel_bind_dev(dev);
900 if (set_mtu)
901 WRITE_ONCE(dev->mtu, mtu);
902 }
903 dst_cache_reset(&t->dst_cache);
904 netdev_state_change(dev);
905}
906
907int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm_kern *p,
908 int cmd)
909{
910 int err = 0;
911 struct ip_tunnel *t = netdev_priv(dev);
912 struct net *net = t->net;
913 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
914
915 switch (cmd) {
916 case SIOCGETTUNNEL:
917 if (dev == itn->fb_tunnel_dev) {
918 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
919 if (!t)
920 t = netdev_priv(dev);
921 }
922 memcpy(p, &t->parms, sizeof(*p));
923 break;
924
925 case SIOCADDTUNNEL:
926 case SIOCCHGTUNNEL:
927 err = -EPERM;
928 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
929 goto done;
930 if (p->iph.ttl)
931 p->iph.frag_off |= htons(IP_DF);
932 if (!test_bit(IP_TUNNEL_VTI_BIT, p->i_flags)) {
933 if (!test_bit(IP_TUNNEL_KEY_BIT, p->i_flags))
934 p->i_key = 0;
935 if (!test_bit(IP_TUNNEL_KEY_BIT, p->o_flags))
936 p->o_key = 0;
937 }
938
939 t = ip_tunnel_find(itn, p, itn->type);
940
941 if (cmd == SIOCADDTUNNEL) {
942 if (!t) {
943 t = ip_tunnel_create(net, itn, p);
944 err = PTR_ERR_OR_ZERO(t);
945 break;
946 }
947
948 err = -EEXIST;
949 break;
950 }
951 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
952 if (t) {
953 if (t->dev != dev) {
954 err = -EEXIST;
955 break;
956 }
957 } else {
958 unsigned int nflags = 0;
959
960 if (ipv4_is_multicast(p->iph.daddr))
961 nflags = IFF_BROADCAST;
962 else if (p->iph.daddr)
963 nflags = IFF_POINTOPOINT;
964
965 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
966 err = -EINVAL;
967 break;
968 }
969
970 t = netdev_priv(dev);
971 }
972 }
973
974 if (t) {
975 err = 0;
976 ip_tunnel_update(itn, t, dev, p, true, 0);
977 } else {
978 err = -ENOENT;
979 }
980 break;
981
982 case SIOCDELTUNNEL:
983 err = -EPERM;
984 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
985 goto done;
986
987 if (dev == itn->fb_tunnel_dev) {
988 err = -ENOENT;
989 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
990 if (!t)
991 goto done;
992 err = -EPERM;
993 if (t == netdev_priv(itn->fb_tunnel_dev))
994 goto done;
995 dev = t->dev;
996 }
997 unregister_netdevice(dev);
998 err = 0;
999 break;
1000
1001 default:
1002 err = -EINVAL;
1003 }
1004
1005done:
1006 return err;
1007}
1008EXPORT_SYMBOL_GPL(ip_tunnel_ctl);
1009
1010bool ip_tunnel_parm_from_user(struct ip_tunnel_parm_kern *kp,
1011 const void __user *data)
1012{
1013 struct ip_tunnel_parm p;
1014
1015 if (copy_from_user(&p, data, sizeof(p)))
1016 return false;
1017
1018 strscpy(kp->name, p.name);
1019 kp->link = p.link;
1020 ip_tunnel_flags_from_be16(kp->i_flags, p.i_flags);
1021 ip_tunnel_flags_from_be16(kp->o_flags, p.o_flags);
1022 kp->i_key = p.i_key;
1023 kp->o_key = p.o_key;
1024 memcpy(&kp->iph, &p.iph, min(sizeof(kp->iph), sizeof(p.iph)));
1025
1026 return true;
1027}
1028EXPORT_SYMBOL_GPL(ip_tunnel_parm_from_user);
1029
1030bool ip_tunnel_parm_to_user(void __user *data, struct ip_tunnel_parm_kern *kp)
1031{
1032 struct ip_tunnel_parm p;
1033
1034 if (!ip_tunnel_flags_is_be16_compat(kp->i_flags) ||
1035 !ip_tunnel_flags_is_be16_compat(kp->o_flags))
1036 return false;
1037
1038 memset(&p, 0, sizeof(p));
1039
1040 strscpy(p.name, kp->name);
1041 p.link = kp->link;
1042 p.i_flags = ip_tunnel_flags_to_be16(kp->i_flags);
1043 p.o_flags = ip_tunnel_flags_to_be16(kp->o_flags);
1044 p.i_key = kp->i_key;
1045 p.o_key = kp->o_key;
1046 memcpy(&p.iph, &kp->iph, min(sizeof(p.iph), sizeof(kp->iph)));
1047
1048 return !copy_to_user(data, &p, sizeof(p));
1049}
1050EXPORT_SYMBOL_GPL(ip_tunnel_parm_to_user);
1051
1052int ip_tunnel_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
1053 void __user *data, int cmd)
1054{
1055 struct ip_tunnel_parm_kern p;
1056 int err;
1057
1058 if (!ip_tunnel_parm_from_user(&p, data))
1059 return -EFAULT;
1060 err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, cmd);
1061 if (!err && !ip_tunnel_parm_to_user(data, &p))
1062 return -EFAULT;
1063 return err;
1064}
1065EXPORT_SYMBOL_GPL(ip_tunnel_siocdevprivate);
1066
1067int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
1068{
1069 struct ip_tunnel *tunnel = netdev_priv(dev);
1070 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1071 int max_mtu = IP_MAX_MTU - t_hlen;
1072
1073 if (dev->type == ARPHRD_ETHER)
1074 max_mtu -= dev->hard_header_len;
1075
1076 if (new_mtu < ETH_MIN_MTU)
1077 return -EINVAL;
1078
1079 if (new_mtu > max_mtu) {
1080 if (strict)
1081 return -EINVAL;
1082
1083 new_mtu = max_mtu;
1084 }
1085
1086 WRITE_ONCE(dev->mtu, new_mtu);
1087 return 0;
1088}
1089EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu);
1090
1091int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1092{
1093 return __ip_tunnel_change_mtu(dev, new_mtu, true);
1094}
1095EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
1096
1097static void ip_tunnel_dev_free(struct net_device *dev)
1098{
1099 struct ip_tunnel *tunnel = netdev_priv(dev);
1100
1101 gro_cells_destroy(&tunnel->gro_cells);
1102 dst_cache_destroy(&tunnel->dst_cache);
1103}
1104
1105void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
1106{
1107 struct ip_tunnel *tunnel = netdev_priv(dev);
1108 struct ip_tunnel_net *itn;
1109
1110 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
1111
1112 if (itn->fb_tunnel_dev != dev) {
1113 ip_tunnel_del(itn, netdev_priv(dev));
1114 unregister_netdevice_queue(dev, head);
1115 }
1116}
1117EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
1118
1119struct net *ip_tunnel_get_link_net(const struct net_device *dev)
1120{
1121 struct ip_tunnel *tunnel = netdev_priv(dev);
1122
1123 return READ_ONCE(tunnel->net);
1124}
1125EXPORT_SYMBOL(ip_tunnel_get_link_net);
1126
1127int ip_tunnel_get_iflink(const struct net_device *dev)
1128{
1129 const struct ip_tunnel *tunnel = netdev_priv(dev);
1130
1131 return READ_ONCE(tunnel->parms.link);
1132}
1133EXPORT_SYMBOL(ip_tunnel_get_iflink);
1134
1135int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
1136 struct rtnl_link_ops *ops, char *devname)
1137{
1138 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
1139 struct ip_tunnel_parm_kern parms;
1140 unsigned int i;
1141
1142 itn->rtnl_link_ops = ops;
1143 for (i = 0; i < IP_TNL_HASH_SIZE; i++)
1144 INIT_HLIST_HEAD(&itn->tunnels[i]);
1145
1146 if (!ops || !net_has_fallback_tunnels(net)) {
1147 struct ip_tunnel_net *it_init_net;
1148
1149 it_init_net = net_generic(&init_net, ip_tnl_net_id);
1150 itn->type = it_init_net->type;
1151 itn->fb_tunnel_dev = NULL;
1152 return 0;
1153 }
1154
1155 memset(&parms, 0, sizeof(parms));
1156 if (devname)
1157 strscpy(parms.name, devname, IFNAMSIZ);
1158
1159 rtnl_lock();
1160 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
1161 /* FB netdevice is special: we have one, and only one per netns.
1162 * Allowing to move it to another netns is clearly unsafe.
1163 */
1164 if (!IS_ERR(itn->fb_tunnel_dev)) {
1165 itn->fb_tunnel_dev->netns_local = true;
1166 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
1167 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
1168 itn->type = itn->fb_tunnel_dev->type;
1169 }
1170 rtnl_unlock();
1171
1172 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
1173}
1174EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
1175
1176static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn,
1177 struct list_head *head,
1178 struct rtnl_link_ops *ops)
1179{
1180 struct net_device *dev, *aux;
1181 int h;
1182
1183 for_each_netdev_safe(net, dev, aux)
1184 if (dev->rtnl_link_ops == ops)
1185 unregister_netdevice_queue(dev, head);
1186
1187 for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
1188 struct ip_tunnel *t;
1189 struct hlist_node *n;
1190 struct hlist_head *thead = &itn->tunnels[h];
1191
1192 hlist_for_each_entry_safe(t, n, thead, hash_node)
1193 /* If dev is in the same netns, it has already
1194 * been added to the list by the previous loop.
1195 */
1196 if (!net_eq(dev_net(t->dev), net))
1197 unregister_netdevice_queue(t->dev, head);
1198 }
1199}
1200
1201void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id,
1202 struct rtnl_link_ops *ops,
1203 struct list_head *dev_to_kill)
1204{
1205 struct ip_tunnel_net *itn;
1206 struct net *net;
1207
1208 ASSERT_RTNL();
1209 list_for_each_entry(net, net_list, exit_list) {
1210 itn = net_generic(net, id);
1211 ip_tunnel_destroy(net, itn, dev_to_kill, ops);
1212 }
1213}
1214EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets);
1215
1216int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
1217 struct ip_tunnel_parm_kern *p, __u32 fwmark)
1218{
1219 struct ip_tunnel *nt;
1220 struct net *net = dev_net(dev);
1221 struct ip_tunnel_net *itn;
1222 int mtu;
1223 int err;
1224
1225 nt = netdev_priv(dev);
1226 itn = net_generic(net, nt->ip_tnl_net_id);
1227
1228 if (nt->collect_md) {
1229 if (rtnl_dereference(itn->collect_md_tun))
1230 return -EEXIST;
1231 } else {
1232 if (ip_tunnel_find(itn, p, dev->type))
1233 return -EEXIST;
1234 }
1235
1236 nt->net = net;
1237 nt->parms = *p;
1238 nt->fwmark = fwmark;
1239 err = register_netdevice(dev);
1240 if (err)
1241 goto err_register_netdevice;
1242
1243 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1244 eth_hw_addr_random(dev);
1245
1246 mtu = ip_tunnel_bind_dev(dev);
1247 if (tb[IFLA_MTU]) {
1248 unsigned int max = IP_MAX_MTU - (nt->hlen + sizeof(struct iphdr));
1249
1250 if (dev->type == ARPHRD_ETHER)
1251 max -= dev->hard_header_len;
1252
1253 mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU, max);
1254 }
1255
1256 err = dev_set_mtu(dev, mtu);
1257 if (err)
1258 goto err_dev_set_mtu;
1259
1260 ip_tunnel_add(itn, nt);
1261 return 0;
1262
1263err_dev_set_mtu:
1264 unregister_netdevice(dev);
1265err_register_netdevice:
1266 return err;
1267}
1268EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
1269
1270int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
1271 struct ip_tunnel_parm_kern *p, __u32 fwmark)
1272{
1273 struct ip_tunnel *t;
1274 struct ip_tunnel *tunnel = netdev_priv(dev);
1275 struct net *net = tunnel->net;
1276 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
1277
1278 if (dev == itn->fb_tunnel_dev)
1279 return -EINVAL;
1280
1281 t = ip_tunnel_find(itn, p, dev->type);
1282
1283 if (t) {
1284 if (t->dev != dev)
1285 return -EEXIST;
1286 } else {
1287 t = tunnel;
1288
1289 if (dev->type != ARPHRD_ETHER) {
1290 unsigned int nflags = 0;
1291
1292 if (ipv4_is_multicast(p->iph.daddr))
1293 nflags = IFF_BROADCAST;
1294 else if (p->iph.daddr)
1295 nflags = IFF_POINTOPOINT;
1296
1297 if ((dev->flags ^ nflags) &
1298 (IFF_POINTOPOINT | IFF_BROADCAST))
1299 return -EINVAL;
1300 }
1301 }
1302
1303 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark);
1304 return 0;
1305}
1306EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1307
1308int ip_tunnel_init(struct net_device *dev)
1309{
1310 struct ip_tunnel *tunnel = netdev_priv(dev);
1311 struct iphdr *iph = &tunnel->parms.iph;
1312 int err;
1313
1314 dev->needs_free_netdev = true;
1315 dev->priv_destructor = ip_tunnel_dev_free;
1316 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1317
1318 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1319 if (err)
1320 return err;
1321
1322 err = gro_cells_init(&tunnel->gro_cells, dev);
1323 if (err) {
1324 dst_cache_destroy(&tunnel->dst_cache);
1325 return err;
1326 }
1327
1328 tunnel->dev = dev;
1329 tunnel->net = dev_net(dev);
1330 strscpy(tunnel->parms.name, dev->name);
1331 iph->version = 4;
1332 iph->ihl = 5;
1333
1334 if (tunnel->collect_md)
1335 netif_keep_dst(dev);
1336 netdev_lockdep_set_classes(dev);
1337 return 0;
1338}
1339EXPORT_SYMBOL_GPL(ip_tunnel_init);
1340
1341void ip_tunnel_uninit(struct net_device *dev)
1342{
1343 struct ip_tunnel *tunnel = netdev_priv(dev);
1344 struct net *net = tunnel->net;
1345 struct ip_tunnel_net *itn;
1346
1347 itn = net_generic(net, tunnel->ip_tnl_net_id);
1348 ip_tunnel_del(itn, netdev_priv(dev));
1349 if (itn->fb_tunnel_dev == dev)
1350 WRITE_ONCE(itn->fb_tunnel_dev, NULL);
1351
1352 dst_cache_reset(&tunnel->dst_cache);
1353}
1354EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1355
1356/* Do least required initialization, rest of init is done in tunnel_init call */
1357void ip_tunnel_setup(struct net_device *dev, unsigned int net_id)
1358{
1359 struct ip_tunnel *tunnel = netdev_priv(dev);
1360 tunnel->ip_tnl_net_id = net_id;
1361}
1362EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1363
1364MODULE_DESCRIPTION("IPv4 tunnel implementation library");
1365MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2013 Nicira, Inc.
4 */
5
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8#include <linux/capability.h>
9#include <linux/module.h>
10#include <linux/types.h>
11#include <linux/kernel.h>
12#include <linux/slab.h>
13#include <linux/uaccess.h>
14#include <linux/skbuff.h>
15#include <linux/netdevice.h>
16#include <linux/in.h>
17#include <linux/tcp.h>
18#include <linux/udp.h>
19#include <linux/if_arp.h>
20#include <linux/init.h>
21#include <linux/in6.h>
22#include <linux/inetdevice.h>
23#include <linux/igmp.h>
24#include <linux/netfilter_ipv4.h>
25#include <linux/etherdevice.h>
26#include <linux/if_ether.h>
27#include <linux/if_vlan.h>
28#include <linux/rculist.h>
29#include <linux/err.h>
30
31#include <net/sock.h>
32#include <net/ip.h>
33#include <net/icmp.h>
34#include <net/protocol.h>
35#include <net/ip_tunnels.h>
36#include <net/arp.h>
37#include <net/checksum.h>
38#include <net/dsfield.h>
39#include <net/inet_ecn.h>
40#include <net/xfrm.h>
41#include <net/net_namespace.h>
42#include <net/netns/generic.h>
43#include <net/rtnetlink.h>
44#include <net/udp.h>
45#include <net/dst_metadata.h>
46
47#if IS_ENABLED(CONFIG_IPV6)
48#include <net/ipv6.h>
49#include <net/ip6_fib.h>
50#include <net/ip6_route.h>
51#endif
52
53static unsigned int ip_tunnel_hash(__be32 key, __be32 remote)
54{
55 return hash_32((__force u32)key ^ (__force u32)remote,
56 IP_TNL_HASH_BITS);
57}
58
59static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p,
60 __be16 flags, __be32 key)
61{
62 if (p->i_flags & TUNNEL_KEY) {
63 if (flags & TUNNEL_KEY)
64 return key == p->i_key;
65 else
66 /* key expected, none present */
67 return false;
68 } else
69 return !(flags & TUNNEL_KEY);
70}
71
72/* Fallback tunnel: no source, no destination, no key, no options
73
74 Tunnel hash table:
75 We require exact key match i.e. if a key is present in packet
76 it will match only tunnel with the same key; if it is not present,
77 it will match only keyless tunnel.
78
79 All keysless packets, if not matched configured keyless tunnels
80 will match fallback tunnel.
81 Given src, dst and key, find appropriate for input tunnel.
82*/
83struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
84 int link, __be16 flags,
85 __be32 remote, __be32 local,
86 __be32 key)
87{
88 struct ip_tunnel *t, *cand = NULL;
89 struct hlist_head *head;
90 struct net_device *ndev;
91 unsigned int hash;
92
93 hash = ip_tunnel_hash(key, remote);
94 head = &itn->tunnels[hash];
95
96 hlist_for_each_entry_rcu(t, head, hash_node) {
97 if (local != t->parms.iph.saddr ||
98 remote != t->parms.iph.daddr ||
99 !(t->dev->flags & IFF_UP))
100 continue;
101
102 if (!ip_tunnel_key_match(&t->parms, flags, key))
103 continue;
104
105 if (t->parms.link == link)
106 return t;
107 else
108 cand = t;
109 }
110
111 hlist_for_each_entry_rcu(t, head, hash_node) {
112 if (remote != t->parms.iph.daddr ||
113 t->parms.iph.saddr != 0 ||
114 !(t->dev->flags & IFF_UP))
115 continue;
116
117 if (!ip_tunnel_key_match(&t->parms, flags, key))
118 continue;
119
120 if (t->parms.link == link)
121 return t;
122 else if (!cand)
123 cand = t;
124 }
125
126 hash = ip_tunnel_hash(key, 0);
127 head = &itn->tunnels[hash];
128
129 hlist_for_each_entry_rcu(t, head, hash_node) {
130 if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) &&
131 (local != t->parms.iph.daddr || !ipv4_is_multicast(local)))
132 continue;
133
134 if (!(t->dev->flags & IFF_UP))
135 continue;
136
137 if (!ip_tunnel_key_match(&t->parms, flags, key))
138 continue;
139
140 if (t->parms.link == link)
141 return t;
142 else if (!cand)
143 cand = t;
144 }
145
146 hlist_for_each_entry_rcu(t, head, hash_node) {
147 if ((!(flags & TUNNEL_NO_KEY) && t->parms.i_key != key) ||
148 t->parms.iph.saddr != 0 ||
149 t->parms.iph.daddr != 0 ||
150 !(t->dev->flags & IFF_UP))
151 continue;
152
153 if (t->parms.link == link)
154 return t;
155 else if (!cand)
156 cand = t;
157 }
158
159 if (cand)
160 return cand;
161
162 t = rcu_dereference(itn->collect_md_tun);
163 if (t && t->dev->flags & IFF_UP)
164 return t;
165
166 ndev = READ_ONCE(itn->fb_tunnel_dev);
167 if (ndev && ndev->flags & IFF_UP)
168 return netdev_priv(ndev);
169
170 return NULL;
171}
172EXPORT_SYMBOL_GPL(ip_tunnel_lookup);
173
174static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn,
175 struct ip_tunnel_parm *parms)
176{
177 unsigned int h;
178 __be32 remote;
179 __be32 i_key = parms->i_key;
180
181 if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr))
182 remote = parms->iph.daddr;
183 else
184 remote = 0;
185
186 if (!(parms->i_flags & TUNNEL_KEY) && (parms->i_flags & VTI_ISVTI))
187 i_key = 0;
188
189 h = ip_tunnel_hash(i_key, remote);
190 return &itn->tunnels[h];
191}
192
193static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t)
194{
195 struct hlist_head *head = ip_bucket(itn, &t->parms);
196
197 if (t->collect_md)
198 rcu_assign_pointer(itn->collect_md_tun, t);
199 hlist_add_head_rcu(&t->hash_node, head);
200}
201
202static void ip_tunnel_del(struct ip_tunnel_net *itn, struct ip_tunnel *t)
203{
204 if (t->collect_md)
205 rcu_assign_pointer(itn->collect_md_tun, NULL);
206 hlist_del_init_rcu(&t->hash_node);
207}
208
209static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn,
210 struct ip_tunnel_parm *parms,
211 int type)
212{
213 __be32 remote = parms->iph.daddr;
214 __be32 local = parms->iph.saddr;
215 __be32 key = parms->i_key;
216 __be16 flags = parms->i_flags;
217 int link = parms->link;
218 struct ip_tunnel *t = NULL;
219 struct hlist_head *head = ip_bucket(itn, parms);
220
221 hlist_for_each_entry_rcu(t, head, hash_node) {
222 if (local == t->parms.iph.saddr &&
223 remote == t->parms.iph.daddr &&
224 link == t->parms.link &&
225 type == t->dev->type &&
226 ip_tunnel_key_match(&t->parms, flags, key))
227 break;
228 }
229 return t;
230}
231
232static struct net_device *__ip_tunnel_create(struct net *net,
233 const struct rtnl_link_ops *ops,
234 struct ip_tunnel_parm *parms)
235{
236 int err;
237 struct ip_tunnel *tunnel;
238 struct net_device *dev;
239 char name[IFNAMSIZ];
240
241 err = -E2BIG;
242 if (parms->name[0]) {
243 if (!dev_valid_name(parms->name))
244 goto failed;
245 strscpy(name, parms->name, IFNAMSIZ);
246 } else {
247 if (strlen(ops->kind) > (IFNAMSIZ - 3))
248 goto failed;
249 strcpy(name, ops->kind);
250 strcat(name, "%d");
251 }
252
253 ASSERT_RTNL();
254 dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup);
255 if (!dev) {
256 err = -ENOMEM;
257 goto failed;
258 }
259 dev_net_set(dev, net);
260
261 dev->rtnl_link_ops = ops;
262
263 tunnel = netdev_priv(dev);
264 tunnel->parms = *parms;
265 tunnel->net = net;
266
267 err = register_netdevice(dev);
268 if (err)
269 goto failed_free;
270
271 return dev;
272
273failed_free:
274 free_netdev(dev);
275failed:
276 return ERR_PTR(err);
277}
278
279static int ip_tunnel_bind_dev(struct net_device *dev)
280{
281 struct net_device *tdev = NULL;
282 struct ip_tunnel *tunnel = netdev_priv(dev);
283 const struct iphdr *iph;
284 int hlen = LL_MAX_HEADER;
285 int mtu = ETH_DATA_LEN;
286 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
287
288 iph = &tunnel->parms.iph;
289
290 /* Guess output device to choose reasonable mtu and needed_headroom */
291 if (iph->daddr) {
292 struct flowi4 fl4;
293 struct rtable *rt;
294
295 ip_tunnel_init_flow(&fl4, iph->protocol, iph->daddr,
296 iph->saddr, tunnel->parms.o_key,
297 RT_TOS(iph->tos), dev_net(dev),
298 tunnel->parms.link, tunnel->fwmark, 0, 0);
299 rt = ip_route_output_key(tunnel->net, &fl4);
300
301 if (!IS_ERR(rt)) {
302 tdev = rt->dst.dev;
303 ip_rt_put(rt);
304 }
305 if (dev->type != ARPHRD_ETHER)
306 dev->flags |= IFF_POINTOPOINT;
307
308 dst_cache_reset(&tunnel->dst_cache);
309 }
310
311 if (!tdev && tunnel->parms.link)
312 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
313
314 if (tdev) {
315 hlen = tdev->hard_header_len + tdev->needed_headroom;
316 mtu = min(tdev->mtu, IP_MAX_MTU);
317 }
318
319 dev->needed_headroom = t_hlen + hlen;
320 mtu -= t_hlen + (dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0);
321
322 if (mtu < IPV4_MIN_MTU)
323 mtu = IPV4_MIN_MTU;
324
325 return mtu;
326}
327
328static struct ip_tunnel *ip_tunnel_create(struct net *net,
329 struct ip_tunnel_net *itn,
330 struct ip_tunnel_parm *parms)
331{
332 struct ip_tunnel *nt;
333 struct net_device *dev;
334 int t_hlen;
335 int mtu;
336 int err;
337
338 dev = __ip_tunnel_create(net, itn->rtnl_link_ops, parms);
339 if (IS_ERR(dev))
340 return ERR_CAST(dev);
341
342 mtu = ip_tunnel_bind_dev(dev);
343 err = dev_set_mtu(dev, mtu);
344 if (err)
345 goto err_dev_set_mtu;
346
347 nt = netdev_priv(dev);
348 t_hlen = nt->hlen + sizeof(struct iphdr);
349 dev->min_mtu = ETH_MIN_MTU;
350 dev->max_mtu = IP_MAX_MTU - t_hlen;
351 if (dev->type == ARPHRD_ETHER)
352 dev->max_mtu -= dev->hard_header_len;
353
354 ip_tunnel_add(itn, nt);
355 return nt;
356
357err_dev_set_mtu:
358 unregister_netdevice(dev);
359 return ERR_PTR(err);
360}
361
362void ip_tunnel_md_udp_encap(struct sk_buff *skb, struct ip_tunnel_info *info)
363{
364 const struct iphdr *iph = ip_hdr(skb);
365 const struct udphdr *udph;
366
367 if (iph->protocol != IPPROTO_UDP)
368 return;
369
370 udph = (struct udphdr *)((__u8 *)iph + (iph->ihl << 2));
371 info->encap.sport = udph->source;
372 info->encap.dport = udph->dest;
373}
374EXPORT_SYMBOL(ip_tunnel_md_udp_encap);
375
376int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
377 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
378 bool log_ecn_error)
379{
380 const struct iphdr *iph = ip_hdr(skb);
381 int err;
382
383#ifdef CONFIG_NET_IPGRE_BROADCAST
384 if (ipv4_is_multicast(iph->daddr)) {
385 DEV_STATS_INC(tunnel->dev, multicast);
386 skb->pkt_type = PACKET_BROADCAST;
387 }
388#endif
389
390 if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) ||
391 ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) {
392 DEV_STATS_INC(tunnel->dev, rx_crc_errors);
393 DEV_STATS_INC(tunnel->dev, rx_errors);
394 goto drop;
395 }
396
397 if (tunnel->parms.i_flags&TUNNEL_SEQ) {
398 if (!(tpi->flags&TUNNEL_SEQ) ||
399 (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
400 DEV_STATS_INC(tunnel->dev, rx_fifo_errors);
401 DEV_STATS_INC(tunnel->dev, rx_errors);
402 goto drop;
403 }
404 tunnel->i_seqno = ntohl(tpi->seq) + 1;
405 }
406
407 skb_set_network_header(skb, (tunnel->dev->type == ARPHRD_ETHER) ? ETH_HLEN : 0);
408
409 err = IP_ECN_decapsulate(iph, skb);
410 if (unlikely(err)) {
411 if (log_ecn_error)
412 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
413 &iph->saddr, iph->tos);
414 if (err > 1) {
415 DEV_STATS_INC(tunnel->dev, rx_frame_errors);
416 DEV_STATS_INC(tunnel->dev, rx_errors);
417 goto drop;
418 }
419 }
420
421 dev_sw_netstats_rx_add(tunnel->dev, skb->len);
422 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
423
424 if (tunnel->dev->type == ARPHRD_ETHER) {
425 skb->protocol = eth_type_trans(skb, tunnel->dev);
426 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
427 } else {
428 skb->dev = tunnel->dev;
429 }
430
431 if (tun_dst)
432 skb_dst_set(skb, (struct dst_entry *)tun_dst);
433
434 gro_cells_receive(&tunnel->gro_cells, skb);
435 return 0;
436
437drop:
438 if (tun_dst)
439 dst_release((struct dst_entry *)tun_dst);
440 kfree_skb(skb);
441 return 0;
442}
443EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
444
445int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops,
446 unsigned int num)
447{
448 if (num >= MAX_IPTUN_ENCAP_OPS)
449 return -ERANGE;
450
451 return !cmpxchg((const struct ip_tunnel_encap_ops **)
452 &iptun_encaps[num],
453 NULL, ops) ? 0 : -1;
454}
455EXPORT_SYMBOL(ip_tunnel_encap_add_ops);
456
457int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops,
458 unsigned int num)
459{
460 int ret;
461
462 if (num >= MAX_IPTUN_ENCAP_OPS)
463 return -ERANGE;
464
465 ret = (cmpxchg((const struct ip_tunnel_encap_ops **)
466 &iptun_encaps[num],
467 ops, NULL) == ops) ? 0 : -1;
468
469 synchronize_net();
470
471 return ret;
472}
473EXPORT_SYMBOL(ip_tunnel_encap_del_ops);
474
475int ip_tunnel_encap_setup(struct ip_tunnel *t,
476 struct ip_tunnel_encap *ipencap)
477{
478 int hlen;
479
480 memset(&t->encap, 0, sizeof(t->encap));
481
482 hlen = ip_encap_hlen(ipencap);
483 if (hlen < 0)
484 return hlen;
485
486 t->encap.type = ipencap->type;
487 t->encap.sport = ipencap->sport;
488 t->encap.dport = ipencap->dport;
489 t->encap.flags = ipencap->flags;
490
491 t->encap_hlen = hlen;
492 t->hlen = t->encap_hlen + t->tun_hlen;
493
494 return 0;
495}
496EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup);
497
498static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
499 struct rtable *rt, __be16 df,
500 const struct iphdr *inner_iph,
501 int tunnel_hlen, __be32 dst, bool md)
502{
503 struct ip_tunnel *tunnel = netdev_priv(dev);
504 int pkt_size;
505 int mtu;
506
507 tunnel_hlen = md ? tunnel_hlen : tunnel->hlen;
508 pkt_size = skb->len - tunnel_hlen;
509 pkt_size -= dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0;
510
511 if (df) {
512 mtu = dst_mtu(&rt->dst) - (sizeof(struct iphdr) + tunnel_hlen);
513 mtu -= dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0;
514 } else {
515 mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
516 }
517
518 if (skb_valid_dst(skb))
519 skb_dst_update_pmtu_no_confirm(skb, mtu);
520
521 if (skb->protocol == htons(ETH_P_IP)) {
522 if (!skb_is_gso(skb) &&
523 (inner_iph->frag_off & htons(IP_DF)) &&
524 mtu < pkt_size) {
525 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
526 return -E2BIG;
527 }
528 }
529#if IS_ENABLED(CONFIG_IPV6)
530 else if (skb->protocol == htons(ETH_P_IPV6)) {
531 struct rt6_info *rt6;
532 __be32 daddr;
533
534 rt6 = skb_valid_dst(skb) ? (struct rt6_info *)skb_dst(skb) :
535 NULL;
536 daddr = md ? dst : tunnel->parms.iph.daddr;
537
538 if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
539 mtu >= IPV6_MIN_MTU) {
540 if ((daddr && !ipv4_is_multicast(daddr)) ||
541 rt6->rt6i_dst.plen == 128) {
542 rt6->rt6i_flags |= RTF_MODIFIED;
543 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
544 }
545 }
546
547 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
548 mtu < pkt_size) {
549 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
550 return -E2BIG;
551 }
552 }
553#endif
554 return 0;
555}
556
557static void ip_tunnel_adj_headroom(struct net_device *dev, unsigned int headroom)
558{
559 /* we must cap headroom to some upperlimit, else pskb_expand_head
560 * will overflow header offsets in skb_headers_offset_update().
561 */
562 static const unsigned int max_allowed = 512;
563
564 if (headroom > max_allowed)
565 headroom = max_allowed;
566
567 if (headroom > READ_ONCE(dev->needed_headroom))
568 WRITE_ONCE(dev->needed_headroom, headroom);
569}
570
571void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
572 u8 proto, int tunnel_hlen)
573{
574 struct ip_tunnel *tunnel = netdev_priv(dev);
575 u32 headroom = sizeof(struct iphdr);
576 struct ip_tunnel_info *tun_info;
577 const struct ip_tunnel_key *key;
578 const struct iphdr *inner_iph;
579 struct rtable *rt = NULL;
580 struct flowi4 fl4;
581 __be16 df = 0;
582 u8 tos, ttl;
583 bool use_cache;
584
585 tun_info = skb_tunnel_info(skb);
586 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
587 ip_tunnel_info_af(tun_info) != AF_INET))
588 goto tx_error;
589 key = &tun_info->key;
590 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
591 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
592 tos = key->tos;
593 if (tos == 1) {
594 if (skb->protocol == htons(ETH_P_IP))
595 tos = inner_iph->tos;
596 else if (skb->protocol == htons(ETH_P_IPV6))
597 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
598 }
599 ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src,
600 tunnel_id_to_key32(key->tun_id), RT_TOS(tos),
601 dev_net(dev), 0, skb->mark, skb_get_hash(skb),
602 key->flow_flags);
603
604 if (!tunnel_hlen)
605 tunnel_hlen = ip_encap_hlen(&tun_info->encap);
606
607 if (ip_tunnel_encap(skb, &tun_info->encap, &proto, &fl4) < 0)
608 goto tx_error;
609
610 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
611 if (use_cache)
612 rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl4.saddr);
613 if (!rt) {
614 rt = ip_route_output_key(tunnel->net, &fl4);
615 if (IS_ERR(rt)) {
616 DEV_STATS_INC(dev, tx_carrier_errors);
617 goto tx_error;
618 }
619 if (use_cache)
620 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
621 fl4.saddr);
622 }
623 if (rt->dst.dev == dev) {
624 ip_rt_put(rt);
625 DEV_STATS_INC(dev, collisions);
626 goto tx_error;
627 }
628
629 if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
630 df = htons(IP_DF);
631 if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, tunnel_hlen,
632 key->u.ipv4.dst, true)) {
633 ip_rt_put(rt);
634 goto tx_error;
635 }
636
637 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
638 ttl = key->ttl;
639 if (ttl == 0) {
640 if (skb->protocol == htons(ETH_P_IP))
641 ttl = inner_iph->ttl;
642 else if (skb->protocol == htons(ETH_P_IPV6))
643 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
644 else
645 ttl = ip4_dst_hoplimit(&rt->dst);
646 }
647
648 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
649 if (skb_cow_head(skb, headroom)) {
650 ip_rt_put(rt);
651 goto tx_dropped;
652 }
653
654 ip_tunnel_adj_headroom(dev, headroom);
655
656 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl,
657 df, !net_eq(tunnel->net, dev_net(dev)));
658 return;
659tx_error:
660 DEV_STATS_INC(dev, tx_errors);
661 goto kfree;
662tx_dropped:
663 DEV_STATS_INC(dev, tx_dropped);
664kfree:
665 kfree_skb(skb);
666}
667EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
668
669void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
670 const struct iphdr *tnl_params, u8 protocol)
671{
672 struct ip_tunnel *tunnel = netdev_priv(dev);
673 struct ip_tunnel_info *tun_info = NULL;
674 const struct iphdr *inner_iph;
675 unsigned int max_headroom; /* The extra header space needed */
676 struct rtable *rt = NULL; /* Route to the other host */
677 __be16 payload_protocol;
678 bool use_cache = false;
679 struct flowi4 fl4;
680 bool md = false;
681 bool connected;
682 u8 tos, ttl;
683 __be32 dst;
684 __be16 df;
685
686 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
687 connected = (tunnel->parms.iph.daddr != 0);
688 payload_protocol = skb_protocol(skb, true);
689
690 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
691
692 dst = tnl_params->daddr;
693 if (dst == 0) {
694 /* NBMA tunnel */
695
696 if (!skb_dst(skb)) {
697 DEV_STATS_INC(dev, tx_fifo_errors);
698 goto tx_error;
699 }
700
701 tun_info = skb_tunnel_info(skb);
702 if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX) &&
703 ip_tunnel_info_af(tun_info) == AF_INET &&
704 tun_info->key.u.ipv4.dst) {
705 dst = tun_info->key.u.ipv4.dst;
706 md = true;
707 connected = true;
708 } else if (payload_protocol == htons(ETH_P_IP)) {
709 rt = skb_rtable(skb);
710 dst = rt_nexthop(rt, inner_iph->daddr);
711 }
712#if IS_ENABLED(CONFIG_IPV6)
713 else if (payload_protocol == htons(ETH_P_IPV6)) {
714 const struct in6_addr *addr6;
715 struct neighbour *neigh;
716 bool do_tx_error_icmp;
717 int addr_type;
718
719 neigh = dst_neigh_lookup(skb_dst(skb),
720 &ipv6_hdr(skb)->daddr);
721 if (!neigh)
722 goto tx_error;
723
724 addr6 = (const struct in6_addr *)&neigh->primary_key;
725 addr_type = ipv6_addr_type(addr6);
726
727 if (addr_type == IPV6_ADDR_ANY) {
728 addr6 = &ipv6_hdr(skb)->daddr;
729 addr_type = ipv6_addr_type(addr6);
730 }
731
732 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
733 do_tx_error_icmp = true;
734 else {
735 do_tx_error_icmp = false;
736 dst = addr6->s6_addr32[3];
737 }
738 neigh_release(neigh);
739 if (do_tx_error_icmp)
740 goto tx_error_icmp;
741 }
742#endif
743 else
744 goto tx_error;
745
746 if (!md)
747 connected = false;
748 }
749
750 tos = tnl_params->tos;
751 if (tos & 0x1) {
752 tos &= ~0x1;
753 if (payload_protocol == htons(ETH_P_IP)) {
754 tos = inner_iph->tos;
755 connected = false;
756 } else if (payload_protocol == htons(ETH_P_IPV6)) {
757 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
758 connected = false;
759 }
760 }
761
762 ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr,
763 tunnel->parms.o_key, RT_TOS(tos),
764 dev_net(dev), tunnel->parms.link,
765 tunnel->fwmark, skb_get_hash(skb), 0);
766
767 if (ip_tunnel_encap(skb, &tunnel->encap, &protocol, &fl4) < 0)
768 goto tx_error;
769
770 if (connected && md) {
771 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
772 if (use_cache)
773 rt = dst_cache_get_ip4(&tun_info->dst_cache,
774 &fl4.saddr);
775 } else {
776 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache,
777 &fl4.saddr) : NULL;
778 }
779
780 if (!rt) {
781 rt = ip_route_output_key(tunnel->net, &fl4);
782
783 if (IS_ERR(rt)) {
784 DEV_STATS_INC(dev, tx_carrier_errors);
785 goto tx_error;
786 }
787 if (use_cache)
788 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
789 fl4.saddr);
790 else if (!md && connected)
791 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst,
792 fl4.saddr);
793 }
794
795 if (rt->dst.dev == dev) {
796 ip_rt_put(rt);
797 DEV_STATS_INC(dev, collisions);
798 goto tx_error;
799 }
800
801 df = tnl_params->frag_off;
802 if (payload_protocol == htons(ETH_P_IP) && !tunnel->ignore_df)
803 df |= (inner_iph->frag_off & htons(IP_DF));
804
805 if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, 0, 0, false)) {
806 ip_rt_put(rt);
807 goto tx_error;
808 }
809
810 if (tunnel->err_count > 0) {
811 if (time_before(jiffies,
812 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
813 tunnel->err_count--;
814
815 dst_link_failure(skb);
816 } else
817 tunnel->err_count = 0;
818 }
819
820 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
821 ttl = tnl_params->ttl;
822 if (ttl == 0) {
823 if (payload_protocol == htons(ETH_P_IP))
824 ttl = inner_iph->ttl;
825#if IS_ENABLED(CONFIG_IPV6)
826 else if (payload_protocol == htons(ETH_P_IPV6))
827 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
828#endif
829 else
830 ttl = ip4_dst_hoplimit(&rt->dst);
831 }
832
833 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
834 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap);
835
836 if (skb_cow_head(skb, max_headroom)) {
837 ip_rt_put(rt);
838 DEV_STATS_INC(dev, tx_dropped);
839 kfree_skb(skb);
840 return;
841 }
842
843 ip_tunnel_adj_headroom(dev, max_headroom);
844
845 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
846 df, !net_eq(tunnel->net, dev_net(dev)));
847 return;
848
849#if IS_ENABLED(CONFIG_IPV6)
850tx_error_icmp:
851 dst_link_failure(skb);
852#endif
853tx_error:
854 DEV_STATS_INC(dev, tx_errors);
855 kfree_skb(skb);
856}
857EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
858
859static void ip_tunnel_update(struct ip_tunnel_net *itn,
860 struct ip_tunnel *t,
861 struct net_device *dev,
862 struct ip_tunnel_parm *p,
863 bool set_mtu,
864 __u32 fwmark)
865{
866 ip_tunnel_del(itn, t);
867 t->parms.iph.saddr = p->iph.saddr;
868 t->parms.iph.daddr = p->iph.daddr;
869 t->parms.i_key = p->i_key;
870 t->parms.o_key = p->o_key;
871 if (dev->type != ARPHRD_ETHER) {
872 __dev_addr_set(dev, &p->iph.saddr, 4);
873 memcpy(dev->broadcast, &p->iph.daddr, 4);
874 }
875 ip_tunnel_add(itn, t);
876
877 t->parms.iph.ttl = p->iph.ttl;
878 t->parms.iph.tos = p->iph.tos;
879 t->parms.iph.frag_off = p->iph.frag_off;
880
881 if (t->parms.link != p->link || t->fwmark != fwmark) {
882 int mtu;
883
884 t->parms.link = p->link;
885 t->fwmark = fwmark;
886 mtu = ip_tunnel_bind_dev(dev);
887 if (set_mtu)
888 dev->mtu = mtu;
889 }
890 dst_cache_reset(&t->dst_cache);
891 netdev_state_change(dev);
892}
893
894int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
895{
896 int err = 0;
897 struct ip_tunnel *t = netdev_priv(dev);
898 struct net *net = t->net;
899 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
900
901 switch (cmd) {
902 case SIOCGETTUNNEL:
903 if (dev == itn->fb_tunnel_dev) {
904 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
905 if (!t)
906 t = netdev_priv(dev);
907 }
908 memcpy(p, &t->parms, sizeof(*p));
909 break;
910
911 case SIOCADDTUNNEL:
912 case SIOCCHGTUNNEL:
913 err = -EPERM;
914 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
915 goto done;
916 if (p->iph.ttl)
917 p->iph.frag_off |= htons(IP_DF);
918 if (!(p->i_flags & VTI_ISVTI)) {
919 if (!(p->i_flags & TUNNEL_KEY))
920 p->i_key = 0;
921 if (!(p->o_flags & TUNNEL_KEY))
922 p->o_key = 0;
923 }
924
925 t = ip_tunnel_find(itn, p, itn->type);
926
927 if (cmd == SIOCADDTUNNEL) {
928 if (!t) {
929 t = ip_tunnel_create(net, itn, p);
930 err = PTR_ERR_OR_ZERO(t);
931 break;
932 }
933
934 err = -EEXIST;
935 break;
936 }
937 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
938 if (t) {
939 if (t->dev != dev) {
940 err = -EEXIST;
941 break;
942 }
943 } else {
944 unsigned int nflags = 0;
945
946 if (ipv4_is_multicast(p->iph.daddr))
947 nflags = IFF_BROADCAST;
948 else if (p->iph.daddr)
949 nflags = IFF_POINTOPOINT;
950
951 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
952 err = -EINVAL;
953 break;
954 }
955
956 t = netdev_priv(dev);
957 }
958 }
959
960 if (t) {
961 err = 0;
962 ip_tunnel_update(itn, t, dev, p, true, 0);
963 } else {
964 err = -ENOENT;
965 }
966 break;
967
968 case SIOCDELTUNNEL:
969 err = -EPERM;
970 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
971 goto done;
972
973 if (dev == itn->fb_tunnel_dev) {
974 err = -ENOENT;
975 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
976 if (!t)
977 goto done;
978 err = -EPERM;
979 if (t == netdev_priv(itn->fb_tunnel_dev))
980 goto done;
981 dev = t->dev;
982 }
983 unregister_netdevice(dev);
984 err = 0;
985 break;
986
987 default:
988 err = -EINVAL;
989 }
990
991done:
992 return err;
993}
994EXPORT_SYMBOL_GPL(ip_tunnel_ctl);
995
996int ip_tunnel_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
997 void __user *data, int cmd)
998{
999 struct ip_tunnel_parm p;
1000 int err;
1001
1002 if (copy_from_user(&p, data, sizeof(p)))
1003 return -EFAULT;
1004 err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, cmd);
1005 if (!err && copy_to_user(data, &p, sizeof(p)))
1006 return -EFAULT;
1007 return err;
1008}
1009EXPORT_SYMBOL_GPL(ip_tunnel_siocdevprivate);
1010
1011int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
1012{
1013 struct ip_tunnel *tunnel = netdev_priv(dev);
1014 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
1015 int max_mtu = IP_MAX_MTU - t_hlen;
1016
1017 if (dev->type == ARPHRD_ETHER)
1018 max_mtu -= dev->hard_header_len;
1019
1020 if (new_mtu < ETH_MIN_MTU)
1021 return -EINVAL;
1022
1023 if (new_mtu > max_mtu) {
1024 if (strict)
1025 return -EINVAL;
1026
1027 new_mtu = max_mtu;
1028 }
1029
1030 dev->mtu = new_mtu;
1031 return 0;
1032}
1033EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu);
1034
1035int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1036{
1037 return __ip_tunnel_change_mtu(dev, new_mtu, true);
1038}
1039EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
1040
1041static void ip_tunnel_dev_free(struct net_device *dev)
1042{
1043 struct ip_tunnel *tunnel = netdev_priv(dev);
1044
1045 gro_cells_destroy(&tunnel->gro_cells);
1046 dst_cache_destroy(&tunnel->dst_cache);
1047 free_percpu(dev->tstats);
1048}
1049
1050void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
1051{
1052 struct ip_tunnel *tunnel = netdev_priv(dev);
1053 struct ip_tunnel_net *itn;
1054
1055 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
1056
1057 if (itn->fb_tunnel_dev != dev) {
1058 ip_tunnel_del(itn, netdev_priv(dev));
1059 unregister_netdevice_queue(dev, head);
1060 }
1061}
1062EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
1063
1064struct net *ip_tunnel_get_link_net(const struct net_device *dev)
1065{
1066 struct ip_tunnel *tunnel = netdev_priv(dev);
1067
1068 return tunnel->net;
1069}
1070EXPORT_SYMBOL(ip_tunnel_get_link_net);
1071
1072int ip_tunnel_get_iflink(const struct net_device *dev)
1073{
1074 struct ip_tunnel *tunnel = netdev_priv(dev);
1075
1076 return tunnel->parms.link;
1077}
1078EXPORT_SYMBOL(ip_tunnel_get_iflink);
1079
1080int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
1081 struct rtnl_link_ops *ops, char *devname)
1082{
1083 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
1084 struct ip_tunnel_parm parms;
1085 unsigned int i;
1086
1087 itn->rtnl_link_ops = ops;
1088 for (i = 0; i < IP_TNL_HASH_SIZE; i++)
1089 INIT_HLIST_HEAD(&itn->tunnels[i]);
1090
1091 if (!ops || !net_has_fallback_tunnels(net)) {
1092 struct ip_tunnel_net *it_init_net;
1093
1094 it_init_net = net_generic(&init_net, ip_tnl_net_id);
1095 itn->type = it_init_net->type;
1096 itn->fb_tunnel_dev = NULL;
1097 return 0;
1098 }
1099
1100 memset(&parms, 0, sizeof(parms));
1101 if (devname)
1102 strscpy(parms.name, devname, IFNAMSIZ);
1103
1104 rtnl_lock();
1105 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
1106 /* FB netdevice is special: we have one, and only one per netns.
1107 * Allowing to move it to another netns is clearly unsafe.
1108 */
1109 if (!IS_ERR(itn->fb_tunnel_dev)) {
1110 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1111 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
1112 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
1113 itn->type = itn->fb_tunnel_dev->type;
1114 }
1115 rtnl_unlock();
1116
1117 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
1118}
1119EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
1120
1121static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn,
1122 struct list_head *head,
1123 struct rtnl_link_ops *ops)
1124{
1125 struct net_device *dev, *aux;
1126 int h;
1127
1128 for_each_netdev_safe(net, dev, aux)
1129 if (dev->rtnl_link_ops == ops)
1130 unregister_netdevice_queue(dev, head);
1131
1132 for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
1133 struct ip_tunnel *t;
1134 struct hlist_node *n;
1135 struct hlist_head *thead = &itn->tunnels[h];
1136
1137 hlist_for_each_entry_safe(t, n, thead, hash_node)
1138 /* If dev is in the same netns, it has already
1139 * been added to the list by the previous loop.
1140 */
1141 if (!net_eq(dev_net(t->dev), net))
1142 unregister_netdevice_queue(t->dev, head);
1143 }
1144}
1145
1146void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id,
1147 struct rtnl_link_ops *ops)
1148{
1149 struct ip_tunnel_net *itn;
1150 struct net *net;
1151 LIST_HEAD(list);
1152
1153 rtnl_lock();
1154 list_for_each_entry(net, net_list, exit_list) {
1155 itn = net_generic(net, id);
1156 ip_tunnel_destroy(net, itn, &list, ops);
1157 }
1158 unregister_netdevice_many(&list);
1159 rtnl_unlock();
1160}
1161EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets);
1162
1163int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
1164 struct ip_tunnel_parm *p, __u32 fwmark)
1165{
1166 struct ip_tunnel *nt;
1167 struct net *net = dev_net(dev);
1168 struct ip_tunnel_net *itn;
1169 int mtu;
1170 int err;
1171
1172 nt = netdev_priv(dev);
1173 itn = net_generic(net, nt->ip_tnl_net_id);
1174
1175 if (nt->collect_md) {
1176 if (rtnl_dereference(itn->collect_md_tun))
1177 return -EEXIST;
1178 } else {
1179 if (ip_tunnel_find(itn, p, dev->type))
1180 return -EEXIST;
1181 }
1182
1183 nt->net = net;
1184 nt->parms = *p;
1185 nt->fwmark = fwmark;
1186 err = register_netdevice(dev);
1187 if (err)
1188 goto err_register_netdevice;
1189
1190 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1191 eth_hw_addr_random(dev);
1192
1193 mtu = ip_tunnel_bind_dev(dev);
1194 if (tb[IFLA_MTU]) {
1195 unsigned int max = IP_MAX_MTU - (nt->hlen + sizeof(struct iphdr));
1196
1197 if (dev->type == ARPHRD_ETHER)
1198 max -= dev->hard_header_len;
1199
1200 mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU, max);
1201 }
1202
1203 err = dev_set_mtu(dev, mtu);
1204 if (err)
1205 goto err_dev_set_mtu;
1206
1207 ip_tunnel_add(itn, nt);
1208 return 0;
1209
1210err_dev_set_mtu:
1211 unregister_netdevice(dev);
1212err_register_netdevice:
1213 return err;
1214}
1215EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
1216
1217int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
1218 struct ip_tunnel_parm *p, __u32 fwmark)
1219{
1220 struct ip_tunnel *t;
1221 struct ip_tunnel *tunnel = netdev_priv(dev);
1222 struct net *net = tunnel->net;
1223 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
1224
1225 if (dev == itn->fb_tunnel_dev)
1226 return -EINVAL;
1227
1228 t = ip_tunnel_find(itn, p, dev->type);
1229
1230 if (t) {
1231 if (t->dev != dev)
1232 return -EEXIST;
1233 } else {
1234 t = tunnel;
1235
1236 if (dev->type != ARPHRD_ETHER) {
1237 unsigned int nflags = 0;
1238
1239 if (ipv4_is_multicast(p->iph.daddr))
1240 nflags = IFF_BROADCAST;
1241 else if (p->iph.daddr)
1242 nflags = IFF_POINTOPOINT;
1243
1244 if ((dev->flags ^ nflags) &
1245 (IFF_POINTOPOINT | IFF_BROADCAST))
1246 return -EINVAL;
1247 }
1248 }
1249
1250 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark);
1251 return 0;
1252}
1253EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1254
1255int ip_tunnel_init(struct net_device *dev)
1256{
1257 struct ip_tunnel *tunnel = netdev_priv(dev);
1258 struct iphdr *iph = &tunnel->parms.iph;
1259 int err;
1260
1261 dev->needs_free_netdev = true;
1262 dev->priv_destructor = ip_tunnel_dev_free;
1263 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1264 if (!dev->tstats)
1265 return -ENOMEM;
1266
1267 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1268 if (err) {
1269 free_percpu(dev->tstats);
1270 return err;
1271 }
1272
1273 err = gro_cells_init(&tunnel->gro_cells, dev);
1274 if (err) {
1275 dst_cache_destroy(&tunnel->dst_cache);
1276 free_percpu(dev->tstats);
1277 return err;
1278 }
1279
1280 tunnel->dev = dev;
1281 tunnel->net = dev_net(dev);
1282 strcpy(tunnel->parms.name, dev->name);
1283 iph->version = 4;
1284 iph->ihl = 5;
1285
1286 if (tunnel->collect_md)
1287 netif_keep_dst(dev);
1288 return 0;
1289}
1290EXPORT_SYMBOL_GPL(ip_tunnel_init);
1291
1292void ip_tunnel_uninit(struct net_device *dev)
1293{
1294 struct ip_tunnel *tunnel = netdev_priv(dev);
1295 struct net *net = tunnel->net;
1296 struct ip_tunnel_net *itn;
1297
1298 itn = net_generic(net, tunnel->ip_tnl_net_id);
1299 ip_tunnel_del(itn, netdev_priv(dev));
1300 if (itn->fb_tunnel_dev == dev)
1301 WRITE_ONCE(itn->fb_tunnel_dev, NULL);
1302
1303 dst_cache_reset(&tunnel->dst_cache);
1304}
1305EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1306
1307/* Do least required initialization, rest of init is done in tunnel_init call */
1308void ip_tunnel_setup(struct net_device *dev, unsigned int net_id)
1309{
1310 struct ip_tunnel *tunnel = netdev_priv(dev);
1311 tunnel->ip_tnl_net_id = net_id;
1312}
1313EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1314
1315MODULE_DESCRIPTION("IPv4 tunnel implementation library");
1316MODULE_LICENSE("GPL");