Loading...
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 strlcpy(name, ops->kind, IFNAMSIZ);
265 strncat(name, "%d", 2);
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);
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{
506 struct ip_tunnel *tunnel = netdev_priv(dev);
507 int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len;
508 int mtu;
509
510 if (df)
511 mtu = dst_mtu(&rt->dst) - dev->hard_header_len
512 - sizeof(struct iphdr) - tunnel->hlen;
513 else
514 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
515
516 skb_dst_update_pmtu(skb, mtu);
517
518 if (skb->protocol == htons(ETH_P_IP)) {
519 if (!skb_is_gso(skb) &&
520 (inner_iph->frag_off & htons(IP_DF)) &&
521 mtu < pkt_size) {
522 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
523 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
524 return -E2BIG;
525 }
526 }
527#if IS_ENABLED(CONFIG_IPV6)
528 else if (skb->protocol == htons(ETH_P_IPV6)) {
529 struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
530
531 if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
532 mtu >= IPV6_MIN_MTU) {
533 if ((tunnel->parms.iph.daddr &&
534 !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
535 rt6->rt6i_dst.plen == 128) {
536 rt6->rt6i_flags |= RTF_MODIFIED;
537 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
538 }
539 }
540
541 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
542 mtu < pkt_size) {
543 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
544 return -E2BIG;
545 }
546 }
547#endif
548 return 0;
549}
550
551void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
552{
553 struct ip_tunnel *tunnel = netdev_priv(dev);
554 u32 headroom = sizeof(struct iphdr);
555 struct ip_tunnel_info *tun_info;
556 const struct ip_tunnel_key *key;
557 const struct iphdr *inner_iph;
558 struct rtable *rt;
559 struct flowi4 fl4;
560 __be16 df = 0;
561 u8 tos, ttl;
562
563 tun_info = skb_tunnel_info(skb);
564 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
565 ip_tunnel_info_af(tun_info) != AF_INET))
566 goto tx_error;
567 key = &tun_info->key;
568 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
569 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
570 tos = key->tos;
571 if (tos == 1) {
572 if (skb->protocol == htons(ETH_P_IP))
573 tos = inner_iph->tos;
574 else if (skb->protocol == htons(ETH_P_IPV6))
575 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
576 }
577 ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 0,
578 RT_TOS(tos), tunnel->parms.link, tunnel->fwmark);
579 if (tunnel->encap.type != TUNNEL_ENCAP_NONE)
580 goto tx_error;
581 rt = ip_route_output_key(tunnel->net, &fl4);
582 if (IS_ERR(rt)) {
583 dev->stats.tx_carrier_errors++;
584 goto tx_error;
585 }
586 if (rt->dst.dev == dev) {
587 ip_rt_put(rt);
588 dev->stats.collisions++;
589 goto tx_error;
590 }
591 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
592 ttl = key->ttl;
593 if (ttl == 0) {
594 if (skb->protocol == htons(ETH_P_IP))
595 ttl = inner_iph->ttl;
596 else if (skb->protocol == htons(ETH_P_IPV6))
597 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
598 else
599 ttl = ip4_dst_hoplimit(&rt->dst);
600 }
601 if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
602 df = htons(IP_DF);
603 else if (skb->protocol == htons(ETH_P_IP))
604 df = inner_iph->frag_off & htons(IP_DF);
605 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
606 if (headroom > dev->needed_headroom)
607 dev->needed_headroom = headroom;
608
609 if (skb_cow_head(skb, dev->needed_headroom)) {
610 ip_rt_put(rt);
611 goto tx_dropped;
612 }
613 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl,
614 df, !net_eq(tunnel->net, dev_net(dev)));
615 return;
616tx_error:
617 dev->stats.tx_errors++;
618 goto kfree;
619tx_dropped:
620 dev->stats.tx_dropped++;
621kfree:
622 kfree_skb(skb);
623}
624EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
625
626void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
627 const struct iphdr *tnl_params, u8 protocol)
628{
629 struct ip_tunnel *tunnel = netdev_priv(dev);
630 const struct iphdr *inner_iph;
631 struct flowi4 fl4;
632 u8 tos, ttl;
633 __be16 df;
634 struct rtable *rt; /* Route to the other host */
635 unsigned int max_headroom; /* The extra header space needed */
636 __be32 dst;
637 bool connected;
638
639 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
640 connected = (tunnel->parms.iph.daddr != 0);
641
642 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
643
644 dst = tnl_params->daddr;
645 if (dst == 0) {
646 /* NBMA tunnel */
647
648 if (!skb_dst(skb)) {
649 dev->stats.tx_fifo_errors++;
650 goto tx_error;
651 }
652
653 if (skb->protocol == htons(ETH_P_IP)) {
654 rt = skb_rtable(skb);
655 dst = rt_nexthop(rt, inner_iph->daddr);
656 }
657#if IS_ENABLED(CONFIG_IPV6)
658 else if (skb->protocol == htons(ETH_P_IPV6)) {
659 const struct in6_addr *addr6;
660 struct neighbour *neigh;
661 bool do_tx_error_icmp;
662 int addr_type;
663
664 neigh = dst_neigh_lookup(skb_dst(skb),
665 &ipv6_hdr(skb)->daddr);
666 if (!neigh)
667 goto tx_error;
668
669 addr6 = (const struct in6_addr *)&neigh->primary_key;
670 addr_type = ipv6_addr_type(addr6);
671
672 if (addr_type == IPV6_ADDR_ANY) {
673 addr6 = &ipv6_hdr(skb)->daddr;
674 addr_type = ipv6_addr_type(addr6);
675 }
676
677 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
678 do_tx_error_icmp = true;
679 else {
680 do_tx_error_icmp = false;
681 dst = addr6->s6_addr32[3];
682 }
683 neigh_release(neigh);
684 if (do_tx_error_icmp)
685 goto tx_error_icmp;
686 }
687#endif
688 else
689 goto tx_error;
690
691 connected = false;
692 }
693
694 tos = tnl_params->tos;
695 if (tos & 0x1) {
696 tos &= ~0x1;
697 if (skb->protocol == htons(ETH_P_IP)) {
698 tos = inner_iph->tos;
699 connected = false;
700 } else if (skb->protocol == htons(ETH_P_IPV6)) {
701 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
702 connected = false;
703 }
704 }
705
706 ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr,
707 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link,
708 tunnel->fwmark);
709
710 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0)
711 goto tx_error;
712
713 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr) :
714 NULL;
715
716 if (!rt) {
717 rt = ip_route_output_key(tunnel->net, &fl4);
718
719 if (IS_ERR(rt)) {
720 dev->stats.tx_carrier_errors++;
721 goto tx_error;
722 }
723 if (connected)
724 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst,
725 fl4.saddr);
726 }
727
728 if (rt->dst.dev == dev) {
729 ip_rt_put(rt);
730 dev->stats.collisions++;
731 goto tx_error;
732 }
733
734 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) {
735 ip_rt_put(rt);
736 goto tx_error;
737 }
738
739 if (tunnel->err_count > 0) {
740 if (time_before(jiffies,
741 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
742 tunnel->err_count--;
743
744 dst_link_failure(skb);
745 } else
746 tunnel->err_count = 0;
747 }
748
749 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
750 ttl = tnl_params->ttl;
751 if (ttl == 0) {
752 if (skb->protocol == htons(ETH_P_IP))
753 ttl = inner_iph->ttl;
754#if IS_ENABLED(CONFIG_IPV6)
755 else if (skb->protocol == htons(ETH_P_IPV6))
756 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
757#endif
758 else
759 ttl = ip4_dst_hoplimit(&rt->dst);
760 }
761
762 df = tnl_params->frag_off;
763 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df)
764 df |= (inner_iph->frag_off&htons(IP_DF));
765
766 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
767 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap);
768 if (max_headroom > dev->needed_headroom)
769 dev->needed_headroom = max_headroom;
770
771 if (skb_cow_head(skb, dev->needed_headroom)) {
772 ip_rt_put(rt);
773 dev->stats.tx_dropped++;
774 kfree_skb(skb);
775 return;
776 }
777
778 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
779 df, !net_eq(tunnel->net, dev_net(dev)));
780 return;
781
782#if IS_ENABLED(CONFIG_IPV6)
783tx_error_icmp:
784 dst_link_failure(skb);
785#endif
786tx_error:
787 dev->stats.tx_errors++;
788 kfree_skb(skb);
789}
790EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
791
792static void ip_tunnel_update(struct ip_tunnel_net *itn,
793 struct ip_tunnel *t,
794 struct net_device *dev,
795 struct ip_tunnel_parm *p,
796 bool set_mtu,
797 __u32 fwmark)
798{
799 ip_tunnel_del(itn, t);
800 t->parms.iph.saddr = p->iph.saddr;
801 t->parms.iph.daddr = p->iph.daddr;
802 t->parms.i_key = p->i_key;
803 t->parms.o_key = p->o_key;
804 if (dev->type != ARPHRD_ETHER) {
805 memcpy(dev->dev_addr, &p->iph.saddr, 4);
806 memcpy(dev->broadcast, &p->iph.daddr, 4);
807 }
808 ip_tunnel_add(itn, t);
809
810 t->parms.iph.ttl = p->iph.ttl;
811 t->parms.iph.tos = p->iph.tos;
812 t->parms.iph.frag_off = p->iph.frag_off;
813
814 if (t->parms.link != p->link || t->fwmark != fwmark) {
815 int mtu;
816
817 t->parms.link = p->link;
818 t->fwmark = fwmark;
819 mtu = ip_tunnel_bind_dev(dev);
820 if (set_mtu)
821 dev->mtu = mtu;
822 }
823 dst_cache_reset(&t->dst_cache);
824 netdev_state_change(dev);
825}
826
827int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
828{
829 int err = 0;
830 struct ip_tunnel *t = netdev_priv(dev);
831 struct net *net = t->net;
832 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
833
834 switch (cmd) {
835 case SIOCGETTUNNEL:
836 if (dev == itn->fb_tunnel_dev) {
837 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
838 if (!t)
839 t = netdev_priv(dev);
840 }
841 memcpy(p, &t->parms, sizeof(*p));
842 break;
843
844 case SIOCADDTUNNEL:
845 case SIOCCHGTUNNEL:
846 err = -EPERM;
847 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
848 goto done;
849 if (p->iph.ttl)
850 p->iph.frag_off |= htons(IP_DF);
851 if (!(p->i_flags & VTI_ISVTI)) {
852 if (!(p->i_flags & TUNNEL_KEY))
853 p->i_key = 0;
854 if (!(p->o_flags & TUNNEL_KEY))
855 p->o_key = 0;
856 }
857
858 t = ip_tunnel_find(itn, p, itn->type);
859
860 if (cmd == SIOCADDTUNNEL) {
861 if (!t) {
862 t = ip_tunnel_create(net, itn, p);
863 err = PTR_ERR_OR_ZERO(t);
864 break;
865 }
866
867 err = -EEXIST;
868 break;
869 }
870 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
871 if (t) {
872 if (t->dev != dev) {
873 err = -EEXIST;
874 break;
875 }
876 } else {
877 unsigned int nflags = 0;
878
879 if (ipv4_is_multicast(p->iph.daddr))
880 nflags = IFF_BROADCAST;
881 else if (p->iph.daddr)
882 nflags = IFF_POINTOPOINT;
883
884 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
885 err = -EINVAL;
886 break;
887 }
888
889 t = netdev_priv(dev);
890 }
891 }
892
893 if (t) {
894 err = 0;
895 ip_tunnel_update(itn, t, dev, p, true, 0);
896 } else {
897 err = -ENOENT;
898 }
899 break;
900
901 case SIOCDELTUNNEL:
902 err = -EPERM;
903 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
904 goto done;
905
906 if (dev == itn->fb_tunnel_dev) {
907 err = -ENOENT;
908 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
909 if (!t)
910 goto done;
911 err = -EPERM;
912 if (t == netdev_priv(itn->fb_tunnel_dev))
913 goto done;
914 dev = t->dev;
915 }
916 unregister_netdevice(dev);
917 err = 0;
918 break;
919
920 default:
921 err = -EINVAL;
922 }
923
924done:
925 return err;
926}
927EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);
928
929int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
930{
931 struct ip_tunnel *tunnel = netdev_priv(dev);
932 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
933 int max_mtu = IP_MAX_MTU - dev->hard_header_len - t_hlen;
934
935 if (new_mtu < ETH_MIN_MTU)
936 return -EINVAL;
937
938 if (new_mtu > max_mtu) {
939 if (strict)
940 return -EINVAL;
941
942 new_mtu = max_mtu;
943 }
944
945 dev->mtu = new_mtu;
946 return 0;
947}
948EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu);
949
950int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
951{
952 return __ip_tunnel_change_mtu(dev, new_mtu, true);
953}
954EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
955
956static void ip_tunnel_dev_free(struct net_device *dev)
957{
958 struct ip_tunnel *tunnel = netdev_priv(dev);
959
960 gro_cells_destroy(&tunnel->gro_cells);
961 dst_cache_destroy(&tunnel->dst_cache);
962 free_percpu(dev->tstats);
963}
964
965void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
966{
967 struct ip_tunnel *tunnel = netdev_priv(dev);
968 struct ip_tunnel_net *itn;
969
970 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
971
972 if (itn->fb_tunnel_dev != dev) {
973 ip_tunnel_del(itn, netdev_priv(dev));
974 unregister_netdevice_queue(dev, head);
975 }
976}
977EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
978
979struct net *ip_tunnel_get_link_net(const struct net_device *dev)
980{
981 struct ip_tunnel *tunnel = netdev_priv(dev);
982
983 return tunnel->net;
984}
985EXPORT_SYMBOL(ip_tunnel_get_link_net);
986
987int ip_tunnel_get_iflink(const struct net_device *dev)
988{
989 struct ip_tunnel *tunnel = netdev_priv(dev);
990
991 return tunnel->parms.link;
992}
993EXPORT_SYMBOL(ip_tunnel_get_iflink);
994
995int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
996 struct rtnl_link_ops *ops, char *devname)
997{
998 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
999 struct ip_tunnel_parm parms;
1000 unsigned int i;
1001
1002 itn->rtnl_link_ops = ops;
1003 for (i = 0; i < IP_TNL_HASH_SIZE; i++)
1004 INIT_HLIST_HEAD(&itn->tunnels[i]);
1005
1006 if (!ops || !net_has_fallback_tunnels(net)) {
1007 struct ip_tunnel_net *it_init_net;
1008
1009 it_init_net = net_generic(&init_net, ip_tnl_net_id);
1010 itn->type = it_init_net->type;
1011 itn->fb_tunnel_dev = NULL;
1012 return 0;
1013 }
1014
1015 memset(&parms, 0, sizeof(parms));
1016 if (devname)
1017 strlcpy(parms.name, devname, IFNAMSIZ);
1018
1019 rtnl_lock();
1020 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
1021 /* FB netdevice is special: we have one, and only one per netns.
1022 * Allowing to move it to another netns is clearly unsafe.
1023 */
1024 if (!IS_ERR(itn->fb_tunnel_dev)) {
1025 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1026 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
1027 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
1028 itn->type = itn->fb_tunnel_dev->type;
1029 }
1030 rtnl_unlock();
1031
1032 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
1033}
1034EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
1035
1036static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn,
1037 struct list_head *head,
1038 struct rtnl_link_ops *ops)
1039{
1040 struct net_device *dev, *aux;
1041 int h;
1042
1043 for_each_netdev_safe(net, dev, aux)
1044 if (dev->rtnl_link_ops == ops)
1045 unregister_netdevice_queue(dev, head);
1046
1047 for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
1048 struct ip_tunnel *t;
1049 struct hlist_node *n;
1050 struct hlist_head *thead = &itn->tunnels[h];
1051
1052 hlist_for_each_entry_safe(t, n, thead, hash_node)
1053 /* If dev is in the same netns, it has already
1054 * been added to the list by the previous loop.
1055 */
1056 if (!net_eq(dev_net(t->dev), net))
1057 unregister_netdevice_queue(t->dev, head);
1058 }
1059}
1060
1061void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id,
1062 struct rtnl_link_ops *ops)
1063{
1064 struct ip_tunnel_net *itn;
1065 struct net *net;
1066 LIST_HEAD(list);
1067
1068 rtnl_lock();
1069 list_for_each_entry(net, net_list, exit_list) {
1070 itn = net_generic(net, id);
1071 ip_tunnel_destroy(net, itn, &list, ops);
1072 }
1073 unregister_netdevice_many(&list);
1074 rtnl_unlock();
1075}
1076EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets);
1077
1078int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
1079 struct ip_tunnel_parm *p, __u32 fwmark)
1080{
1081 struct ip_tunnel *nt;
1082 struct net *net = dev_net(dev);
1083 struct ip_tunnel_net *itn;
1084 int mtu;
1085 int err;
1086
1087 nt = netdev_priv(dev);
1088 itn = net_generic(net, nt->ip_tnl_net_id);
1089
1090 if (nt->collect_md) {
1091 if (rtnl_dereference(itn->collect_md_tun))
1092 return -EEXIST;
1093 } else {
1094 if (ip_tunnel_find(itn, p, dev->type))
1095 return -EEXIST;
1096 }
1097
1098 nt->net = net;
1099 nt->parms = *p;
1100 nt->fwmark = fwmark;
1101 err = register_netdevice(dev);
1102 if (err)
1103 goto err_register_netdevice;
1104
1105 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1106 eth_hw_addr_random(dev);
1107
1108 mtu = ip_tunnel_bind_dev(dev);
1109 if (tb[IFLA_MTU]) {
1110 unsigned int max = IP_MAX_MTU - dev->hard_header_len - nt->hlen;
1111
1112 mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU,
1113 (unsigned int)(max - sizeof(struct iphdr)));
1114 }
1115
1116 err = dev_set_mtu(dev, mtu);
1117 if (err)
1118 goto err_dev_set_mtu;
1119
1120 ip_tunnel_add(itn, nt);
1121 return 0;
1122
1123err_dev_set_mtu:
1124 unregister_netdevice(dev);
1125err_register_netdevice:
1126 return err;
1127}
1128EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
1129
1130int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
1131 struct ip_tunnel_parm *p, __u32 fwmark)
1132{
1133 struct ip_tunnel *t;
1134 struct ip_tunnel *tunnel = netdev_priv(dev);
1135 struct net *net = tunnel->net;
1136 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
1137
1138 if (dev == itn->fb_tunnel_dev)
1139 return -EINVAL;
1140
1141 t = ip_tunnel_find(itn, p, dev->type);
1142
1143 if (t) {
1144 if (t->dev != dev)
1145 return -EEXIST;
1146 } else {
1147 t = tunnel;
1148
1149 if (dev->type != ARPHRD_ETHER) {
1150 unsigned int nflags = 0;
1151
1152 if (ipv4_is_multicast(p->iph.daddr))
1153 nflags = IFF_BROADCAST;
1154 else if (p->iph.daddr)
1155 nflags = IFF_POINTOPOINT;
1156
1157 if ((dev->flags ^ nflags) &
1158 (IFF_POINTOPOINT | IFF_BROADCAST))
1159 return -EINVAL;
1160 }
1161 }
1162
1163 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark);
1164 return 0;
1165}
1166EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1167
1168int ip_tunnel_init(struct net_device *dev)
1169{
1170 struct ip_tunnel *tunnel = netdev_priv(dev);
1171 struct iphdr *iph = &tunnel->parms.iph;
1172 int err;
1173
1174 dev->needs_free_netdev = true;
1175 dev->priv_destructor = ip_tunnel_dev_free;
1176 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1177 if (!dev->tstats)
1178 return -ENOMEM;
1179
1180 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1181 if (err) {
1182 free_percpu(dev->tstats);
1183 return err;
1184 }
1185
1186 err = gro_cells_init(&tunnel->gro_cells, dev);
1187 if (err) {
1188 dst_cache_destroy(&tunnel->dst_cache);
1189 free_percpu(dev->tstats);
1190 return err;
1191 }
1192
1193 tunnel->dev = dev;
1194 tunnel->net = dev_net(dev);
1195 strcpy(tunnel->parms.name, dev->name);
1196 iph->version = 4;
1197 iph->ihl = 5;
1198
1199 if (tunnel->collect_md) {
1200 dev->features |= NETIF_F_NETNS_LOCAL;
1201 netif_keep_dst(dev);
1202 }
1203 return 0;
1204}
1205EXPORT_SYMBOL_GPL(ip_tunnel_init);
1206
1207void ip_tunnel_uninit(struct net_device *dev)
1208{
1209 struct ip_tunnel *tunnel = netdev_priv(dev);
1210 struct net *net = tunnel->net;
1211 struct ip_tunnel_net *itn;
1212
1213 itn = net_generic(net, tunnel->ip_tnl_net_id);
1214 /* fb_tunnel_dev will be unregisted in net-exit call. */
1215 if (itn->fb_tunnel_dev != dev)
1216 ip_tunnel_del(itn, netdev_priv(dev));
1217
1218 dst_cache_reset(&tunnel->dst_cache);
1219}
1220EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1221
1222/* Do least required initialization, rest of init is done in tunnel_init call */
1223void ip_tunnel_setup(struct net_device *dev, unsigned int net_id)
1224{
1225 struct ip_tunnel *tunnel = netdev_priv(dev);
1226 tunnel->ip_tnl_net_id = net_id;
1227}
1228EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1229
1230MODULE_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");