1/*
2 * Copyright (c) 2013 Nicira, Inc.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16 * 02110-1301, USA
17 */
18
19#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20
21#include <linux/capability.h>
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/kernel.h>
25#include <linux/slab.h>
26#include <linux/uaccess.h>
27#include <linux/skbuff.h>
28#include <linux/netdevice.h>
29#include <linux/in.h>
30#include <linux/tcp.h>
31#include <linux/udp.h>
32#include <linux/if_arp.h>
33#include <linux/init.h>
34#include <linux/in6.h>
35#include <linux/inetdevice.h>
36#include <linux/igmp.h>
37#include <linux/netfilter_ipv4.h>
38#include <linux/etherdevice.h>
39#include <linux/if_ether.h>
40#include <linux/if_vlan.h>
41#include <linux/rculist.h>
42#include <linux/err.h>
43
44#include <net/sock.h>
45#include <net/ip.h>
46#include <net/icmp.h>
47#include <net/protocol.h>
48#include <net/ip_tunnels.h>
49#include <net/arp.h>
50#include <net/checksum.h>
51#include <net/dsfield.h>
52#include <net/inet_ecn.h>
53#include <net/xfrm.h>
54#include <net/net_namespace.h>
55#include <net/netns/generic.h>
56#include <net/rtnetlink.h>
57#include <net/udp.h>
58#include <net/dst_metadata.h>
59
60#if IS_ENABLED(CONFIG_IPV6)
61#include <net/ipv6.h>
62#include <net/ip6_fib.h>
63#include <net/ip6_route.h>
64#endif
65
66static unsigned int ip_tunnel_hash(__be32 key, __be32 remote)
67{
68 return hash_32((__force u32)key ^ (__force u32)remote,
69 IP_TNL_HASH_BITS);
70}
71
72static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p,
73 __be16 flags, __be32 key)
74{
75 if (p->i_flags & TUNNEL_KEY) {
76 if (flags & TUNNEL_KEY)
77 return key == p->i_key;
78 else
79 /* key expected, none present */
80 return false;
81 } else
82 return !(flags & TUNNEL_KEY);
83}
84
85/* Fallback tunnel: no source, no destination, no key, no options
86
87 Tunnel hash table:
88 We require exact key match i.e. if a key is present in packet
89 it will match only tunnel with the same key; if it is not present,
90 it will match only keyless tunnel.
91
92 All keysless packets, if not matched configured keyless tunnels
93 will match fallback tunnel.
94 Given src, dst and key, find appropriate for input tunnel.
95*/
96struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
97 int link, __be16 flags,
98 __be32 remote, __be32 local,
99 __be32 key)
100{
101 unsigned int hash;
102 struct ip_tunnel *t, *cand = NULL;
103 struct hlist_head *head;
104
105 hash = ip_tunnel_hash(key, remote);
106 head = &itn->tunnels[hash];
107
108 hlist_for_each_entry_rcu(t, head, hash_node) {
109 if (local != t->parms.iph.saddr ||
110 remote != t->parms.iph.daddr ||
111 !(t->dev->flags & IFF_UP))
112 continue;
113
114 if (!ip_tunnel_key_match(&t->parms, flags, key))
115 continue;
116
117 if (t->parms.link == link)
118 return t;
119 else
120 cand = t;
121 }
122
123 hlist_for_each_entry_rcu(t, head, hash_node) {
124 if (remote != t->parms.iph.daddr ||
125 t->parms.iph.saddr != 0 ||
126 !(t->dev->flags & IFF_UP))
127 continue;
128
129 if (!ip_tunnel_key_match(&t->parms, flags, key))
130 continue;
131
132 if (t->parms.link == link)
133 return t;
134 else if (!cand)
135 cand = t;
136 }
137
138 hash = ip_tunnel_hash(key, 0);
139 head = &itn->tunnels[hash];
140
141 hlist_for_each_entry_rcu(t, head, hash_node) {
142 if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) &&
143 (local != t->parms.iph.daddr || !ipv4_is_multicast(local)))
144 continue;
145
146 if (!(t->dev->flags & IFF_UP))
147 continue;
148
149 if (!ip_tunnel_key_match(&t->parms, flags, key))
150 continue;
151
152 if (t->parms.link == link)
153 return t;
154 else if (!cand)
155 cand = t;
156 }
157
158 if (flags & TUNNEL_NO_KEY)
159 goto skip_key_lookup;
160
161 hlist_for_each_entry_rcu(t, head, hash_node) {
162 if (t->parms.i_key != key ||
163 t->parms.iph.saddr != 0 ||
164 t->parms.iph.daddr != 0 ||
165 !(t->dev->flags & IFF_UP))
166 continue;
167
168 if (t->parms.link == link)
169 return t;
170 else if (!cand)
171 cand = t;
172 }
173
174skip_key_lookup:
175 if (cand)
176 return cand;
177
178 t = rcu_dereference(itn->collect_md_tun);
179 if (t && t->dev->flags & IFF_UP)
180 return t;
181
182 if (itn->fb_tunnel_dev && itn->fb_tunnel_dev->flags & IFF_UP)
183 return netdev_priv(itn->fb_tunnel_dev);
184
185 return NULL;
186}
187EXPORT_SYMBOL_GPL(ip_tunnel_lookup);
188
189static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn,
190 struct ip_tunnel_parm *parms)
191{
192 unsigned int h;
193 __be32 remote;
194 __be32 i_key = parms->i_key;
195
196 if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr))
197 remote = parms->iph.daddr;
198 else
199 remote = 0;
200
201 if (!(parms->i_flags & TUNNEL_KEY) && (parms->i_flags & VTI_ISVTI))
202 i_key = 0;
203
204 h = ip_tunnel_hash(i_key, remote);
205 return &itn->tunnels[h];
206}
207
208static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t)
209{
210 struct hlist_head *head = ip_bucket(itn, &t->parms);
211
212 if (t->collect_md)
213 rcu_assign_pointer(itn->collect_md_tun, t);
214 hlist_add_head_rcu(&t->hash_node, head);
215}
216
217static void ip_tunnel_del(struct ip_tunnel_net *itn, struct ip_tunnel *t)
218{
219 if (t->collect_md)
220 rcu_assign_pointer(itn->collect_md_tun, NULL);
221 hlist_del_init_rcu(&t->hash_node);
222}
223
224static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn,
225 struct ip_tunnel_parm *parms,
226 int type)
227{
228 __be32 remote = parms->iph.daddr;
229 __be32 local = parms->iph.saddr;
230 __be32 key = parms->i_key;
231 __be16 flags = parms->i_flags;
232 int link = parms->link;
233 struct ip_tunnel *t = NULL;
234 struct hlist_head *head = ip_bucket(itn, parms);
235
236 hlist_for_each_entry_rcu(t, head, hash_node) {
237 if (local == t->parms.iph.saddr &&
238 remote == t->parms.iph.daddr &&
239 link == t->parms.link &&
240 type == t->dev->type &&
241 ip_tunnel_key_match(&t->parms, flags, key))
242 break;
243 }
244 return t;
245}
246
247static struct net_device *__ip_tunnel_create(struct net *net,
248 const struct rtnl_link_ops *ops,
249 struct ip_tunnel_parm *parms)
250{
251 int err;
252 struct ip_tunnel *tunnel;
253 struct net_device *dev;
254 char name[IFNAMSIZ];
255
256 err = -E2BIG;
257 if (parms->name[0]) {
258 if (!dev_valid_name(parms->name))
259 goto failed;
260 strlcpy(name, parms->name, IFNAMSIZ);
261 } else {
262 if (strlen(ops->kind) > (IFNAMSIZ - 3))
263 goto failed;
264 strcpy(name, ops->kind);
265 strcat(name, "%d");
266 }
267
268 ASSERT_RTNL();
269 dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup);
270 if (!dev) {
271 err = -ENOMEM;
272 goto failed;
273 }
274 dev_net_set(dev, net);
275
276 dev->rtnl_link_ops = ops;
277
278 tunnel = netdev_priv(dev);
279 tunnel->parms = *parms;
280 tunnel->net = net;
281
282 err = register_netdevice(dev);
283 if (err)
284 goto failed_free;
285
286 return dev;
287
288failed_free:
289 free_netdev(dev);
290failed:
291 return ERR_PTR(err);
292}
293
294static int ip_tunnel_bind_dev(struct net_device *dev)
295{
296 struct net_device *tdev = NULL;
297 struct ip_tunnel *tunnel = netdev_priv(dev);
298 const struct iphdr *iph;
299 int hlen = LL_MAX_HEADER;
300 int mtu = ETH_DATA_LEN;
301 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
302
303 iph = &tunnel->parms.iph;
304
305 /* Guess output device to choose reasonable mtu and needed_headroom */
306 if (iph->daddr) {
307 struct flowi4 fl4;
308 struct rtable *rt;
309
310 ip_tunnel_init_flow(&fl4, iph->protocol, iph->daddr,
311 iph->saddr, tunnel->parms.o_key,
312 RT_TOS(iph->tos), tunnel->parms.link,
313 tunnel->fwmark, 0);
314 rt = ip_route_output_key(tunnel->net, &fl4);
315
316 if (!IS_ERR(rt)) {
317 tdev = rt->dst.dev;
318 ip_rt_put(rt);
319 }
320 if (dev->type != ARPHRD_ETHER)
321 dev->flags |= IFF_POINTOPOINT;
322
323 dst_cache_reset(&tunnel->dst_cache);
324 }
325
326 if (!tdev && tunnel->parms.link)
327 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
328
329 if (tdev) {
330 hlen = tdev->hard_header_len + tdev->needed_headroom;
331 mtu = min(tdev->mtu, IP_MAX_MTU);
332 }
333
334 dev->needed_headroom = t_hlen + hlen;
335 mtu -= (dev->hard_header_len + t_hlen);
336
337 if (mtu < IPV4_MIN_MTU)
338 mtu = IPV4_MIN_MTU;
339
340 return mtu;
341}
342
343static struct ip_tunnel *ip_tunnel_create(struct net *net,
344 struct ip_tunnel_net *itn,
345 struct ip_tunnel_parm *parms)
346{
347 struct ip_tunnel *nt;
348 struct net_device *dev;
349 int t_hlen;
350 int mtu;
351 int err;
352
353 dev = __ip_tunnel_create(net, itn->rtnl_link_ops, parms);
354 if (IS_ERR(dev))
355 return ERR_CAST(dev);
356
357 mtu = ip_tunnel_bind_dev(dev);
358 err = dev_set_mtu(dev, mtu);
359 if (err)
360 goto err_dev_set_mtu;
361
362 nt = netdev_priv(dev);
363 t_hlen = nt->hlen + sizeof(struct iphdr);
364 dev->min_mtu = ETH_MIN_MTU;
365 dev->max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen;
366 ip_tunnel_add(itn, nt);
367 return nt;
368
369err_dev_set_mtu:
370 unregister_netdevice(dev);
371 return ERR_PTR(err);
372}
373
374int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
375 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
376 bool log_ecn_error)
377{
378 struct pcpu_sw_netstats *tstats;
379 const struct iphdr *iph = ip_hdr(skb);
380 int err;
381
382#ifdef CONFIG_NET_IPGRE_BROADCAST
383 if (ipv4_is_multicast(iph->daddr)) {
384 tunnel->dev->stats.multicast++;
385 skb->pkt_type = PACKET_BROADCAST;
386 }
387#endif
388
389 if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) ||
390 ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) {
391 tunnel->dev->stats.rx_crc_errors++;
392 tunnel->dev->stats.rx_errors++;
393 goto drop;
394 }
395
396 if (tunnel->parms.i_flags&TUNNEL_SEQ) {
397 if (!(tpi->flags&TUNNEL_SEQ) ||
398 (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
399 tunnel->dev->stats.rx_fifo_errors++;
400 tunnel->dev->stats.rx_errors++;
401 goto drop;
402 }
403 tunnel->i_seqno = ntohl(tpi->seq) + 1;
404 }
405
406 skb_reset_network_header(skb);
407
408 err = IP_ECN_decapsulate(iph, skb);
409 if (unlikely(err)) {
410 if (log_ecn_error)
411 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
412 &iph->saddr, iph->tos);
413 if (err > 1) {
414 ++tunnel->dev->stats.rx_frame_errors;
415 ++tunnel->dev->stats.rx_errors;
416 goto drop;
417 }
418 }
419
420 tstats = this_cpu_ptr(tunnel->dev->tstats);
421 u64_stats_update_begin(&tstats->syncp);
422 tstats->rx_packets++;
423 tstats->rx_bytes += skb->len;
424 u64_stats_update_end(&tstats->syncp);
425
426 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
427
428 if (tunnel->dev->type == ARPHRD_ETHER) {
429 skb->protocol = eth_type_trans(skb, tunnel->dev);
430 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
431 } else {
432 skb->dev = tunnel->dev;
433 }
434
435 if (tun_dst)
436 skb_dst_set(skb, (struct dst_entry *)tun_dst);
437
438 gro_cells_receive(&tunnel->gro_cells, skb);
439 return 0;
440
441drop:
442 if (tun_dst)
443 dst_release((struct dst_entry *)tun_dst);
444 kfree_skb(skb);
445 return 0;
446}
447EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
448
449int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops,
450 unsigned int num)
451{
452 if (num >= MAX_IPTUN_ENCAP_OPS)
453 return -ERANGE;
454
455 return !cmpxchg((const struct ip_tunnel_encap_ops **)
456 &iptun_encaps[num],
457 NULL, ops) ? 0 : -1;
458}
459EXPORT_SYMBOL(ip_tunnel_encap_add_ops);
460
461int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops,
462 unsigned int num)
463{
464 int ret;
465
466 if (num >= MAX_IPTUN_ENCAP_OPS)
467 return -ERANGE;
468
469 ret = (cmpxchg((const struct ip_tunnel_encap_ops **)
470 &iptun_encaps[num],
471 ops, NULL) == ops) ? 0 : -1;
472
473 synchronize_net();
474
475 return ret;
476}
477EXPORT_SYMBOL(ip_tunnel_encap_del_ops);
478
479int ip_tunnel_encap_setup(struct ip_tunnel *t,
480 struct ip_tunnel_encap *ipencap)
481{
482 int hlen;
483
484 memset(&t->encap, 0, sizeof(t->encap));
485
486 hlen = ip_encap_hlen(ipencap);
487 if (hlen < 0)
488 return hlen;
489
490 t->encap.type = ipencap->type;
491 t->encap.sport = ipencap->sport;
492 t->encap.dport = ipencap->dport;
493 t->encap.flags = ipencap->flags;
494
495 t->encap_hlen = hlen;
496 t->hlen = t->encap_hlen + t->tun_hlen;
497
498 return 0;
499}
500EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup);
501
502static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
503 struct rtable *rt, __be16 df,
504 const struct iphdr *inner_iph,
505 int tunnel_hlen, __be32 dst, bool md)
506{
507 struct ip_tunnel *tunnel = netdev_priv(dev);
508 int pkt_size;
509 int mtu;
510
511 tunnel_hlen = md ? tunnel_hlen : tunnel->hlen;
512 pkt_size = skb->len - tunnel_hlen - dev->hard_header_len;
513
514 if (df)
515 mtu = dst_mtu(&rt->dst) - dev->hard_header_len
516 - sizeof(struct iphdr) - tunnel_hlen;
517 else
518 mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
519
520 if (skb_valid_dst(skb))
521 skb_dst_update_pmtu(skb, mtu);
522
523 if (skb->protocol == htons(ETH_P_IP)) {
524 if (!skb_is_gso(skb) &&
525 (inner_iph->frag_off & htons(IP_DF)) &&
526 mtu < pkt_size) {
527 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
528 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
529 return -E2BIG;
530 }
531 }
532#if IS_ENABLED(CONFIG_IPV6)
533 else if (skb->protocol == htons(ETH_P_IPV6)) {
534 struct rt6_info *rt6;
535 __be32 daddr;
536
537 rt6 = skb_valid_dst(skb) ? (struct rt6_info *)skb_dst(skb) :
538 NULL;
539 daddr = md ? dst : tunnel->parms.iph.daddr;
540
541 if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
542 mtu >= IPV6_MIN_MTU) {
543 if ((daddr && !ipv4_is_multicast(daddr)) ||
544 rt6->rt6i_dst.plen == 128) {
545 rt6->rt6i_flags |= RTF_MODIFIED;
546 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
547 }
548 }
549
550 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
551 mtu < pkt_size) {
552 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
553 return -E2BIG;
554 }
555 }
556#endif
557 return 0;
558}
559
560void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
561 u8 proto, int tunnel_hlen)
562{
563 struct ip_tunnel *tunnel = netdev_priv(dev);
564 u32 headroom = sizeof(struct iphdr);
565 struct ip_tunnel_info *tun_info;
566 const struct ip_tunnel_key *key;
567 const struct iphdr *inner_iph;
568 struct rtable *rt = NULL;
569 struct flowi4 fl4;
570 __be16 df = 0;
571 u8 tos, ttl;
572 bool use_cache;
573
574 tun_info = skb_tunnel_info(skb);
575 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
576 ip_tunnel_info_af(tun_info) != AF_INET))
577 goto tx_error;
578 key = &tun_info->key;
579 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
580 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
581 tos = key->tos;
582 if (tos == 1) {
583 if (skb->protocol == htons(ETH_P_IP))
584 tos = inner_iph->tos;
585 else if (skb->protocol == htons(ETH_P_IPV6))
586 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
587 }
588 ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src,
589 tunnel_id_to_key32(key->tun_id), RT_TOS(tos),
590 0, skb->mark, skb_get_hash(skb));
591 if (tunnel->encap.type != TUNNEL_ENCAP_NONE)
592 goto tx_error;
593
594 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
595 if (use_cache)
596 rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl4.saddr);
597 if (!rt) {
598 rt = ip_route_output_key(tunnel->net, &fl4);
599 if (IS_ERR(rt)) {
600 dev->stats.tx_carrier_errors++;
601 goto tx_error;
602 }
603 if (use_cache)
604 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
605 fl4.saddr);
606 }
607 if (rt->dst.dev == dev) {
608 ip_rt_put(rt);
609 dev->stats.collisions++;
610 goto tx_error;
611 }
612
613 if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
614 df = htons(IP_DF);
615 if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, tunnel_hlen,
616 key->u.ipv4.dst, true)) {
617 ip_rt_put(rt);
618 goto tx_error;
619 }
620
621 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
622 ttl = key->ttl;
623 if (ttl == 0) {
624 if (skb->protocol == htons(ETH_P_IP))
625 ttl = inner_iph->ttl;
626 else if (skb->protocol == htons(ETH_P_IPV6))
627 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
628 else
629 ttl = ip4_dst_hoplimit(&rt->dst);
630 }
631
632 if (!df && skb->protocol == htons(ETH_P_IP))
633 df = inner_iph->frag_off & htons(IP_DF);
634
635 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
636 if (headroom > dev->needed_headroom)
637 dev->needed_headroom = headroom;
638
639 if (skb_cow_head(skb, dev->needed_headroom)) {
640 ip_rt_put(rt);
641 goto tx_dropped;
642 }
643 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl,
644 df, !net_eq(tunnel->net, dev_net(dev)));
645 return;
646tx_error:
647 dev->stats.tx_errors++;
648 goto kfree;
649tx_dropped:
650 dev->stats.tx_dropped++;
651kfree:
652 kfree_skb(skb);
653}
654EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
655
656void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
657 const struct iphdr *tnl_params, u8 protocol)
658{
659 struct ip_tunnel *tunnel = netdev_priv(dev);
660 struct ip_tunnel_info *tun_info = NULL;
661 const struct iphdr *inner_iph;
662 unsigned int max_headroom; /* The extra header space needed */
663 struct rtable *rt = NULL; /* Route to the other host */
664 bool use_cache = false;
665 struct flowi4 fl4;
666 bool md = false;
667 bool connected;
668 u8 tos, ttl;
669 __be32 dst;
670 __be16 df;
671
672 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
673 connected = (tunnel->parms.iph.daddr != 0);
674
675 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
676
677 dst = tnl_params->daddr;
678 if (dst == 0) {
679 /* NBMA tunnel */
680
681 if (!skb_dst(skb)) {
682 dev->stats.tx_fifo_errors++;
683 goto tx_error;
684 }
685
686 tun_info = skb_tunnel_info(skb);
687 if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX) &&
688 ip_tunnel_info_af(tun_info) == AF_INET &&
689 tun_info->key.u.ipv4.dst) {
690 dst = tun_info->key.u.ipv4.dst;
691 md = true;
692 connected = true;
693 }
694 else if (skb->protocol == htons(ETH_P_IP)) {
695 rt = skb_rtable(skb);
696 dst = rt_nexthop(rt, inner_iph->daddr);
697 }
698#if IS_ENABLED(CONFIG_IPV6)
699 else if (skb->protocol == htons(ETH_P_IPV6)) {
700 const struct in6_addr *addr6;
701 struct neighbour *neigh;
702 bool do_tx_error_icmp;
703 int addr_type;
704
705 neigh = dst_neigh_lookup(skb_dst(skb),
706 &ipv6_hdr(skb)->daddr);
707 if (!neigh)
708 goto tx_error;
709
710 addr6 = (const struct in6_addr *)&neigh->primary_key;
711 addr_type = ipv6_addr_type(addr6);
712
713 if (addr_type == IPV6_ADDR_ANY) {
714 addr6 = &ipv6_hdr(skb)->daddr;
715 addr_type = ipv6_addr_type(addr6);
716 }
717
718 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
719 do_tx_error_icmp = true;
720 else {
721 do_tx_error_icmp = false;
722 dst = addr6->s6_addr32[3];
723 }
724 neigh_release(neigh);
725 if (do_tx_error_icmp)
726 goto tx_error_icmp;
727 }
728#endif
729 else
730 goto tx_error;
731
732 if (!md)
733 connected = false;
734 }
735
736 tos = tnl_params->tos;
737 if (tos & 0x1) {
738 tos &= ~0x1;
739 if (skb->protocol == htons(ETH_P_IP)) {
740 tos = inner_iph->tos;
741 connected = false;
742 } else if (skb->protocol == htons(ETH_P_IPV6)) {
743 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
744 connected = false;
745 }
746 }
747
748 ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr,
749 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link,
750 tunnel->fwmark, skb_get_hash(skb));
751
752 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0)
753 goto tx_error;
754
755 if (connected && md) {
756 use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
757 if (use_cache)
758 rt = dst_cache_get_ip4(&tun_info->dst_cache,
759 &fl4.saddr);
760 } else {
761 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache,
762 &fl4.saddr) : NULL;
763 }
764
765 if (!rt) {
766 rt = ip_route_output_key(tunnel->net, &fl4);
767
768 if (IS_ERR(rt)) {
769 dev->stats.tx_carrier_errors++;
770 goto tx_error;
771 }
772 if (use_cache)
773 dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
774 fl4.saddr);
775 else if (!md && connected)
776 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst,
777 fl4.saddr);
778 }
779
780 if (rt->dst.dev == dev) {
781 ip_rt_put(rt);
782 dev->stats.collisions++;
783 goto tx_error;
784 }
785
786 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph,
787 0, 0, false)) {
788 ip_rt_put(rt);
789 goto tx_error;
790 }
791
792 if (tunnel->err_count > 0) {
793 if (time_before(jiffies,
794 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
795 tunnel->err_count--;
796
797 dst_link_failure(skb);
798 } else
799 tunnel->err_count = 0;
800 }
801
802 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
803 ttl = tnl_params->ttl;
804 if (ttl == 0) {
805 if (skb->protocol == htons(ETH_P_IP))
806 ttl = inner_iph->ttl;
807#if IS_ENABLED(CONFIG_IPV6)
808 else if (skb->protocol == htons(ETH_P_IPV6))
809 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
810#endif
811 else
812 ttl = ip4_dst_hoplimit(&rt->dst);
813 }
814
815 df = tnl_params->frag_off;
816 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df)
817 df |= (inner_iph->frag_off&htons(IP_DF));
818
819 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
820 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap);
821 if (max_headroom > dev->needed_headroom)
822 dev->needed_headroom = max_headroom;
823
824 if (skb_cow_head(skb, dev->needed_headroom)) {
825 ip_rt_put(rt);
826 dev->stats.tx_dropped++;
827 kfree_skb(skb);
828 return;
829 }
830
831 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
832 df, !net_eq(tunnel->net, dev_net(dev)));
833 return;
834
835#if IS_ENABLED(CONFIG_IPV6)
836tx_error_icmp:
837 dst_link_failure(skb);
838#endif
839tx_error:
840 dev->stats.tx_errors++;
841 kfree_skb(skb);
842}
843EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
844
845static void ip_tunnel_update(struct ip_tunnel_net *itn,
846 struct ip_tunnel *t,
847 struct net_device *dev,
848 struct ip_tunnel_parm *p,
849 bool set_mtu,
850 __u32 fwmark)
851{
852 ip_tunnel_del(itn, t);
853 t->parms.iph.saddr = p->iph.saddr;
854 t->parms.iph.daddr = p->iph.daddr;
855 t->parms.i_key = p->i_key;
856 t->parms.o_key = p->o_key;
857 if (dev->type != ARPHRD_ETHER) {
858 memcpy(dev->dev_addr, &p->iph.saddr, 4);
859 memcpy(dev->broadcast, &p->iph.daddr, 4);
860 }
861 ip_tunnel_add(itn, t);
862
863 t->parms.iph.ttl = p->iph.ttl;
864 t->parms.iph.tos = p->iph.tos;
865 t->parms.iph.frag_off = p->iph.frag_off;
866
867 if (t->parms.link != p->link || t->fwmark != fwmark) {
868 int mtu;
869
870 t->parms.link = p->link;
871 t->fwmark = fwmark;
872 mtu = ip_tunnel_bind_dev(dev);
873 if (set_mtu)
874 dev->mtu = mtu;
875 }
876 dst_cache_reset(&t->dst_cache);
877 netdev_state_change(dev);
878}
879
880int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
881{
882 int err = 0;
883 struct ip_tunnel *t = netdev_priv(dev);
884 struct net *net = t->net;
885 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
886
887 switch (cmd) {
888 case SIOCGETTUNNEL:
889 if (dev == itn->fb_tunnel_dev) {
890 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
891 if (!t)
892 t = netdev_priv(dev);
893 }
894 memcpy(p, &t->parms, sizeof(*p));
895 break;
896
897 case SIOCADDTUNNEL:
898 case SIOCCHGTUNNEL:
899 err = -EPERM;
900 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
901 goto done;
902 if (p->iph.ttl)
903 p->iph.frag_off |= htons(IP_DF);
904 if (!(p->i_flags & VTI_ISVTI)) {
905 if (!(p->i_flags & TUNNEL_KEY))
906 p->i_key = 0;
907 if (!(p->o_flags & TUNNEL_KEY))
908 p->o_key = 0;
909 }
910
911 t = ip_tunnel_find(itn, p, itn->type);
912
913 if (cmd == SIOCADDTUNNEL) {
914 if (!t) {
915 t = ip_tunnel_create(net, itn, p);
916 err = PTR_ERR_OR_ZERO(t);
917 break;
918 }
919
920 err = -EEXIST;
921 break;
922 }
923 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
924 if (t) {
925 if (t->dev != dev) {
926 err = -EEXIST;
927 break;
928 }
929 } else {
930 unsigned int nflags = 0;
931
932 if (ipv4_is_multicast(p->iph.daddr))
933 nflags = IFF_BROADCAST;
934 else if (p->iph.daddr)
935 nflags = IFF_POINTOPOINT;
936
937 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
938 err = -EINVAL;
939 break;
940 }
941
942 t = netdev_priv(dev);
943 }
944 }
945
946 if (t) {
947 err = 0;
948 ip_tunnel_update(itn, t, dev, p, true, 0);
949 } else {
950 err = -ENOENT;
951 }
952 break;
953
954 case SIOCDELTUNNEL:
955 err = -EPERM;
956 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
957 goto done;
958
959 if (dev == itn->fb_tunnel_dev) {
960 err = -ENOENT;
961 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
962 if (!t)
963 goto done;
964 err = -EPERM;
965 if (t == netdev_priv(itn->fb_tunnel_dev))
966 goto done;
967 dev = t->dev;
968 }
969 unregister_netdevice(dev);
970 err = 0;
971 break;
972
973 default:
974 err = -EINVAL;
975 }
976
977done:
978 return err;
979}
980EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);
981
982int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
983{
984 struct ip_tunnel *tunnel = netdev_priv(dev);
985 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
986 int max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen;
987
988 if (new_mtu < ETH_MIN_MTU)
989 return -EINVAL;
990
991 if (new_mtu > max_mtu) {
992 if (strict)
993 return -EINVAL;
994
995 new_mtu = max_mtu;
996 }
997
998 dev->mtu = new_mtu;
999 return 0;
1000}
1001EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu);
1002
1003int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1004{
1005 return __ip_tunnel_change_mtu(dev, new_mtu, true);
1006}
1007EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
1008
1009static void ip_tunnel_dev_free(struct net_device *dev)
1010{
1011 struct ip_tunnel *tunnel = netdev_priv(dev);
1012
1013 gro_cells_destroy(&tunnel->gro_cells);
1014 dst_cache_destroy(&tunnel->dst_cache);
1015 free_percpu(dev->tstats);
1016}
1017
1018void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
1019{
1020 struct ip_tunnel *tunnel = netdev_priv(dev);
1021 struct ip_tunnel_net *itn;
1022
1023 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
1024
1025 if (itn->fb_tunnel_dev != dev) {
1026 ip_tunnel_del(itn, netdev_priv(dev));
1027 unregister_netdevice_queue(dev, head);
1028 }
1029}
1030EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
1031
1032struct net *ip_tunnel_get_link_net(const struct net_device *dev)
1033{
1034 struct ip_tunnel *tunnel = netdev_priv(dev);
1035
1036 return tunnel->net;
1037}
1038EXPORT_SYMBOL(ip_tunnel_get_link_net);
1039
1040int ip_tunnel_get_iflink(const struct net_device *dev)
1041{
1042 struct ip_tunnel *tunnel = netdev_priv(dev);
1043
1044 return tunnel->parms.link;
1045}
1046EXPORT_SYMBOL(ip_tunnel_get_iflink);
1047
1048int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
1049 struct rtnl_link_ops *ops, char *devname)
1050{
1051 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
1052 struct ip_tunnel_parm parms;
1053 unsigned int i;
1054
1055 itn->rtnl_link_ops = ops;
1056 for (i = 0; i < IP_TNL_HASH_SIZE; i++)
1057 INIT_HLIST_HEAD(&itn->tunnels[i]);
1058
1059 if (!ops || !net_has_fallback_tunnels(net)) {
1060 struct ip_tunnel_net *it_init_net;
1061
1062 it_init_net = net_generic(&init_net, ip_tnl_net_id);
1063 itn->type = it_init_net->type;
1064 itn->fb_tunnel_dev = NULL;
1065 return 0;
1066 }
1067
1068 memset(&parms, 0, sizeof(parms));
1069 if (devname)
1070 strlcpy(parms.name, devname, IFNAMSIZ);
1071
1072 rtnl_lock();
1073 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
1074 /* FB netdevice is special: we have one, and only one per netns.
1075 * Allowing to move it to another netns is clearly unsafe.
1076 */
1077 if (!IS_ERR(itn->fb_tunnel_dev)) {
1078 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1079 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
1080 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
1081 itn->type = itn->fb_tunnel_dev->type;
1082 }
1083 rtnl_unlock();
1084
1085 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
1086}
1087EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
1088
1089static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn,
1090 struct list_head *head,
1091 struct rtnl_link_ops *ops)
1092{
1093 struct net_device *dev, *aux;
1094 int h;
1095
1096 for_each_netdev_safe(net, dev, aux)
1097 if (dev->rtnl_link_ops == ops)
1098 unregister_netdevice_queue(dev, head);
1099
1100 for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
1101 struct ip_tunnel *t;
1102 struct hlist_node *n;
1103 struct hlist_head *thead = &itn->tunnels[h];
1104
1105 hlist_for_each_entry_safe(t, n, thead, hash_node)
1106 /* If dev is in the same netns, it has already
1107 * been added to the list by the previous loop.
1108 */
1109 if (!net_eq(dev_net(t->dev), net))
1110 unregister_netdevice_queue(t->dev, head);
1111 }
1112}
1113
1114void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id,
1115 struct rtnl_link_ops *ops)
1116{
1117 struct ip_tunnel_net *itn;
1118 struct net *net;
1119 LIST_HEAD(list);
1120
1121 rtnl_lock();
1122 list_for_each_entry(net, net_list, exit_list) {
1123 itn = net_generic(net, id);
1124 ip_tunnel_destroy(net, itn, &list, ops);
1125 }
1126 unregister_netdevice_many(&list);
1127 rtnl_unlock();
1128}
1129EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets);
1130
1131int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
1132 struct ip_tunnel_parm *p, __u32 fwmark)
1133{
1134 struct ip_tunnel *nt;
1135 struct net *net = dev_net(dev);
1136 struct ip_tunnel_net *itn;
1137 int mtu;
1138 int err;
1139
1140 nt = netdev_priv(dev);
1141 itn = net_generic(net, nt->ip_tnl_net_id);
1142
1143 if (nt->collect_md) {
1144 if (rtnl_dereference(itn->collect_md_tun))
1145 return -EEXIST;
1146 } else {
1147 if (ip_tunnel_find(itn, p, dev->type))
1148 return -EEXIST;
1149 }
1150
1151 nt->net = net;
1152 nt->parms = *p;
1153 nt->fwmark = fwmark;
1154 err = register_netdevice(dev);
1155 if (err)
1156 goto err_register_netdevice;
1157
1158 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1159 eth_hw_addr_random(dev);
1160
1161 mtu = ip_tunnel_bind_dev(dev);
1162 if (tb[IFLA_MTU]) {
1163 unsigned int max = IP_MAX_MTU - dev->hard_header_len - nt->hlen;
1164
1165 mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU,
1166 (unsigned int)(max - sizeof(struct iphdr)));
1167 }
1168
1169 err = dev_set_mtu(dev, mtu);
1170 if (err)
1171 goto err_dev_set_mtu;
1172
1173 ip_tunnel_add(itn, nt);
1174 return 0;
1175
1176err_dev_set_mtu:
1177 unregister_netdevice(dev);
1178err_register_netdevice:
1179 return err;
1180}
1181EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
1182
1183int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
1184 struct ip_tunnel_parm *p, __u32 fwmark)
1185{
1186 struct ip_tunnel *t;
1187 struct ip_tunnel *tunnel = netdev_priv(dev);
1188 struct net *net = tunnel->net;
1189 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
1190
1191 if (dev == itn->fb_tunnel_dev)
1192 return -EINVAL;
1193
1194 t = ip_tunnel_find(itn, p, dev->type);
1195
1196 if (t) {
1197 if (t->dev != dev)
1198 return -EEXIST;
1199 } else {
1200 t = tunnel;
1201
1202 if (dev->type != ARPHRD_ETHER) {
1203 unsigned int nflags = 0;
1204
1205 if (ipv4_is_multicast(p->iph.daddr))
1206 nflags = IFF_BROADCAST;
1207 else if (p->iph.daddr)
1208 nflags = IFF_POINTOPOINT;
1209
1210 if ((dev->flags ^ nflags) &
1211 (IFF_POINTOPOINT | IFF_BROADCAST))
1212 return -EINVAL;
1213 }
1214 }
1215
1216 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark);
1217 return 0;
1218}
1219EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1220
1221int ip_tunnel_init(struct net_device *dev)
1222{
1223 struct ip_tunnel *tunnel = netdev_priv(dev);
1224 struct iphdr *iph = &tunnel->parms.iph;
1225 int err;
1226
1227 dev->needs_free_netdev = true;
1228 dev->priv_destructor = ip_tunnel_dev_free;
1229 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1230 if (!dev->tstats)
1231 return -ENOMEM;
1232
1233 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1234 if (err) {
1235 free_percpu(dev->tstats);
1236 return err;
1237 }
1238
1239 err = gro_cells_init(&tunnel->gro_cells, dev);
1240 if (err) {
1241 dst_cache_destroy(&tunnel->dst_cache);
1242 free_percpu(dev->tstats);
1243 return err;
1244 }
1245
1246 tunnel->dev = dev;
1247 tunnel->net = dev_net(dev);
1248 strcpy(tunnel->parms.name, dev->name);
1249 iph->version = 4;
1250 iph->ihl = 5;
1251
1252 if (tunnel->collect_md) {
1253 dev->features |= NETIF_F_NETNS_LOCAL;
1254 netif_keep_dst(dev);
1255 }
1256 return 0;
1257}
1258EXPORT_SYMBOL_GPL(ip_tunnel_init);
1259
1260void ip_tunnel_uninit(struct net_device *dev)
1261{
1262 struct ip_tunnel *tunnel = netdev_priv(dev);
1263 struct net *net = tunnel->net;
1264 struct ip_tunnel_net *itn;
1265
1266 itn = net_generic(net, tunnel->ip_tnl_net_id);
1267 /* fb_tunnel_dev will be unregisted in net-exit call. */
1268 if (itn->fb_tunnel_dev != dev)
1269 ip_tunnel_del(itn, netdev_priv(dev));
1270
1271 dst_cache_reset(&tunnel->dst_cache);
1272}
1273EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1274
1275/* Do least required initialization, rest of init is done in tunnel_init call */
1276void ip_tunnel_setup(struct net_device *dev, unsigned int net_id)
1277{
1278 struct ip_tunnel *tunnel = netdev_priv(dev);
1279 tunnel->ip_tnl_net_id = net_id;
1280}
1281EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1282
1283MODULE_LICENSE("GPL");
1284