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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / net / ipv4 / ip_tunnel.c
blob6d21068f9b5531e34c0f8be180e2b835fdaae0d7
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
66 static 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
72 static 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 */
96 struct 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
174 skip_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 }
187 EXPORT_SYMBOL_GPL(ip_tunnel_lookup);
188
189 static 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
208 static 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
217 static 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
224 static 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
247 static 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 if (parms->name[0])
257 strlcpy(name, parms->name, IFNAMSIZ);
258 else {
259 if (strlen(ops->kind) > (IFNAMSIZ - 3)) {
260 err = -E2BIG;
261 goto failed;
262 }
263 strlcpy(name, ops->kind, IFNAMSIZ);
264 strncat(name, "%d", 2);
265 }
266
267 ASSERT_RTNL();
268 dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup);
269 if (!dev) {
270 err = -ENOMEM;
271 goto failed;
272 }
273 dev_net_set(dev, net);
274
275 dev->rtnl_link_ops = ops;
276
277 tunnel = netdev_priv(dev);
278 tunnel->parms = *parms;
279 tunnel->net = net;
280
281 err = register_netdevice(dev);
282 if (err)
283 goto failed_free;
284
285 return dev;
286
287 failed_free:
288 free_netdev(dev);
289 failed:
290 return ERR_PTR(err);
291 }
292
293 static inline void init_tunnel_flow(struct flowi4 *fl4,
294 int proto,
295 __be32 daddr, __be32 saddr,
296 __be32 key, __u8 tos, int oif,
297 __u32 mark)
298 {
299 memset(fl4, 0, sizeof(*fl4));
300 fl4->flowi4_oif = oif;
301 fl4->daddr = daddr;
302 fl4->saddr = saddr;
303 fl4->flowi4_tos = tos;
304 fl4->flowi4_proto = proto;
305 fl4->fl4_gre_key = key;
306 fl4->flowi4_mark = mark;
307 }
308
309 static int ip_tunnel_bind_dev(struct net_device *dev)
310 {
311 struct net_device *tdev = NULL;
312 struct ip_tunnel *tunnel = netdev_priv(dev);
313 const struct iphdr *iph;
314 int hlen = LL_MAX_HEADER;
315 int mtu = ETH_DATA_LEN;
316 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
317
318 iph = &tunnel->parms.iph;
319
320 /* Guess output device to choose reasonable mtu and needed_headroom */
321 if (iph->daddr) {
322 struct flowi4 fl4;
323 struct rtable *rt;
324
325 init_tunnel_flow(&fl4, iph->protocol, iph->daddr,
326 iph->saddr, tunnel->parms.o_key,
327 RT_TOS(iph->tos), tunnel->parms.link,
328 tunnel->fwmark);
329 rt = ip_route_output_key(tunnel->net, &fl4);
330
331 if (!IS_ERR(rt)) {
332 tdev = rt->dst.dev;
333 ip_rt_put(rt);
334 }
335 if (dev->type != ARPHRD_ETHER)
336 dev->flags |= IFF_POINTOPOINT;
337
338 dst_cache_reset(&tunnel->dst_cache);
339 }
340
341 if (!tdev && tunnel->parms.link)
342 tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
343
344 if (tdev) {
345 hlen = tdev->hard_header_len + tdev->needed_headroom;
346 mtu = tdev->mtu;
347 }
348
349 dev->needed_headroom = t_hlen + hlen;
350 mtu -= (dev->hard_header_len + t_hlen);
351
352 if (mtu < IPV4_MIN_MTU)
353 mtu = IPV4_MIN_MTU;
354
355 return mtu;
356 }
357
358 static struct ip_tunnel *ip_tunnel_create(struct net *net,
359 struct ip_tunnel_net *itn,
360 struct ip_tunnel_parm *parms)
361 {
362 struct ip_tunnel *nt;
363 struct net_device *dev;
364 int t_hlen;
365
366 BUG_ON(!itn->fb_tunnel_dev);
367 dev = __ip_tunnel_create(net, itn->fb_tunnel_dev->rtnl_link_ops, parms);
368 if (IS_ERR(dev))
369 return ERR_CAST(dev);
370
371 dev->mtu = ip_tunnel_bind_dev(dev);
372
373 nt = netdev_priv(dev);
374 t_hlen = nt->hlen + sizeof(struct iphdr);
375 dev->min_mtu = ETH_MIN_MTU;
376 dev->max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen;
377 ip_tunnel_add(itn, nt);
378 return nt;
379 }
380
381 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
382 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
383 bool log_ecn_error)
384 {
385 struct pcpu_sw_netstats *tstats;
386 const struct iphdr *iph = ip_hdr(skb);
387 int err;
388
389 #ifdef CONFIG_NET_IPGRE_BROADCAST
390 if (ipv4_is_multicast(iph->daddr)) {
391 tunnel->dev->stats.multicast++;
392 skb->pkt_type = PACKET_BROADCAST;
393 }
394 #endif
395
396 if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) ||
397 ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) {
398 tunnel->dev->stats.rx_crc_errors++;
399 tunnel->dev->stats.rx_errors++;
400 goto drop;
401 }
402
403 if (tunnel->parms.i_flags&TUNNEL_SEQ) {
404 if (!(tpi->flags&TUNNEL_SEQ) ||
405 (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) {
406 tunnel->dev->stats.rx_fifo_errors++;
407 tunnel->dev->stats.rx_errors++;
408 goto drop;
409 }
410 tunnel->i_seqno = ntohl(tpi->seq) + 1;
411 }
412
413 skb_reset_network_header(skb);
414
415 err = IP_ECN_decapsulate(iph, skb);
416 if (unlikely(err)) {
417 if (log_ecn_error)
418 net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
419 &iph->saddr, iph->tos);
420 if (err > 1) {
421 ++tunnel->dev->stats.rx_frame_errors;
422 ++tunnel->dev->stats.rx_errors;
423 goto drop;
424 }
425 }
426
427 tstats = this_cpu_ptr(tunnel->dev->tstats);
428 u64_stats_update_begin(&tstats->syncp);
429 tstats->rx_packets++;
430 tstats->rx_bytes += skb->len;
431 u64_stats_update_end(&tstats->syncp);
432
433 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));
434
435 if (tunnel->dev->type == ARPHRD_ETHER) {
436 skb->protocol = eth_type_trans(skb, tunnel->dev);
437 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
438 } else {
439 skb->dev = tunnel->dev;
440 }
441
442 if (tun_dst)
443 skb_dst_set(skb, (struct dst_entry *)tun_dst);
444
445 gro_cells_receive(&tunnel->gro_cells, skb);
446 return 0;
447
448 drop:
449 if (tun_dst)
450 dst_release((struct dst_entry *)tun_dst);
451 kfree_skb(skb);
452 return 0;
453 }
454 EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
455
456 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops,
457 unsigned int num)
458 {
459 if (num >= MAX_IPTUN_ENCAP_OPS)
460 return -ERANGE;
461
462 return !cmpxchg((const struct ip_tunnel_encap_ops **)
463 &iptun_encaps[num],
464 NULL, ops) ? 0 : -1;
465 }
466 EXPORT_SYMBOL(ip_tunnel_encap_add_ops);
467
468 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops,
469 unsigned int num)
470 {
471 int ret;
472
473 if (num >= MAX_IPTUN_ENCAP_OPS)
474 return -ERANGE;
475
476 ret = (cmpxchg((const struct ip_tunnel_encap_ops **)
477 &iptun_encaps[num],
478 ops, NULL) == ops) ? 0 : -1;
479
480 synchronize_net();
481
482 return ret;
483 }
484 EXPORT_SYMBOL(ip_tunnel_encap_del_ops);
485
486 int ip_tunnel_encap_setup(struct ip_tunnel *t,
487 struct ip_tunnel_encap *ipencap)
488 {
489 int hlen;
490
491 memset(&t->encap, 0, sizeof(t->encap));
492
493 hlen = ip_encap_hlen(ipencap);
494 if (hlen < 0)
495 return hlen;
496
497 t->encap.type = ipencap->type;
498 t->encap.sport = ipencap->sport;
499 t->encap.dport = ipencap->dport;
500 t->encap.flags = ipencap->flags;
501
502 t->encap_hlen = hlen;
503 t->hlen = t->encap_hlen + t->tun_hlen;
504
505 return 0;
506 }
507 EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup);
508
509 static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
510 struct rtable *rt, __be16 df,
511 const struct iphdr *inner_iph)
512 {
513 struct ip_tunnel *tunnel = netdev_priv(dev);
514 int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len;
515 int mtu;
516
517 if (df)
518 mtu = dst_mtu(&rt->dst) - dev->hard_header_len
519 - sizeof(struct iphdr) - tunnel->hlen;
520 else
521 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
522
523 skb_dst_update_pmtu(skb, mtu);
524
525 if (skb->protocol == htons(ETH_P_IP)) {
526 if (!skb_is_gso(skb) &&
527 (inner_iph->frag_off & htons(IP_DF)) &&
528 mtu < pkt_size) {
529 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
530 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
531 return -E2BIG;
532 }
533 }
534 #if IS_ENABLED(CONFIG_IPV6)
535 else if (skb->protocol == htons(ETH_P_IPV6)) {
536 struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
537
538 if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
539 mtu >= IPV6_MIN_MTU) {
540 if ((tunnel->parms.iph.daddr &&
541 !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
542 rt6->rt6i_dst.plen == 128) {
543 rt6->rt6i_flags |= RTF_MODIFIED;
544 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
545 }
546 }
547
548 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
549 mtu < pkt_size) {
550 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
551 return -E2BIG;
552 }
553 }
554 #endif
555 return 0;
556 }
557
558 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
559 {
560 struct ip_tunnel *tunnel = netdev_priv(dev);
561 u32 headroom = sizeof(struct iphdr);
562 struct ip_tunnel_info *tun_info;
563 const struct ip_tunnel_key *key;
564 const struct iphdr *inner_iph;
565 struct rtable *rt;
566 struct flowi4 fl4;
567 __be16 df = 0;
568 u8 tos, ttl;
569
570 tun_info = skb_tunnel_info(skb);
571 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
572 ip_tunnel_info_af(tun_info) != AF_INET))
573 goto tx_error;
574 key = &tun_info->key;
575 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
576 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
577 tos = key->tos;
578 if (tos == 1) {
579 if (skb->protocol == htons(ETH_P_IP))
580 tos = inner_iph->tos;
581 else if (skb->protocol == htons(ETH_P_IPV6))
582 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
583 }
584 init_tunnel_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 0,
585 RT_TOS(tos), tunnel->parms.link, tunnel->fwmark);
586 if (tunnel->encap.type != TUNNEL_ENCAP_NONE)
587 goto tx_error;
588 rt = ip_route_output_key(tunnel->net, &fl4);
589 if (IS_ERR(rt)) {
590 dev->stats.tx_carrier_errors++;
591 goto tx_error;
592 }
593 if (rt->dst.dev == dev) {
594 ip_rt_put(rt);
595 dev->stats.collisions++;
596 goto tx_error;
597 }
598 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
599 ttl = key->ttl;
600 if (ttl == 0) {
601 if (skb->protocol == htons(ETH_P_IP))
602 ttl = inner_iph->ttl;
603 else if (skb->protocol == htons(ETH_P_IPV6))
604 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
605 else
606 ttl = ip4_dst_hoplimit(&rt->dst);
607 }
608 if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
609 df = htons(IP_DF);
610 else if (skb->protocol == htons(ETH_P_IP))
611 df = inner_iph->frag_off & htons(IP_DF);
612 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
613 if (headroom > dev->needed_headroom)
614 dev->needed_headroom = headroom;
615
616 if (skb_cow_head(skb, dev->needed_headroom)) {
617 ip_rt_put(rt);
618 goto tx_dropped;
619 }
620 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl,
621 df, !net_eq(tunnel->net, dev_net(dev)));
622 return;
623 tx_error:
624 dev->stats.tx_errors++;
625 goto kfree;
626 tx_dropped:
627 dev->stats.tx_dropped++;
628 kfree:
629 kfree_skb(skb);
630 }
631 EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
632
633 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
634 const struct iphdr *tnl_params, u8 protocol)
635 {
636 struct ip_tunnel *tunnel = netdev_priv(dev);
637 const struct iphdr *inner_iph;
638 struct flowi4 fl4;
639 u8 tos, ttl;
640 __be16 df;
641 struct rtable *rt; /* Route to the other host */
642 unsigned int max_headroom; /* The extra header space needed */
643 __be32 dst;
644 bool connected;
645
646 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
647 connected = (tunnel->parms.iph.daddr != 0);
648
649 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
650
651 dst = tnl_params->daddr;
652 if (dst == 0) {
653 /* NBMA tunnel */
654
655 if (!skb_dst(skb)) {
656 dev->stats.tx_fifo_errors++;
657 goto tx_error;
658 }
659
660 if (skb->protocol == htons(ETH_P_IP)) {
661 rt = skb_rtable(skb);
662 dst = rt_nexthop(rt, inner_iph->daddr);
663 }
664 #if IS_ENABLED(CONFIG_IPV6)
665 else if (skb->protocol == htons(ETH_P_IPV6)) {
666 const struct in6_addr *addr6;
667 struct neighbour *neigh;
668 bool do_tx_error_icmp;
669 int addr_type;
670
671 neigh = dst_neigh_lookup(skb_dst(skb),
672 &ipv6_hdr(skb)->daddr);
673 if (!neigh)
674 goto tx_error;
675
676 addr6 = (const struct in6_addr *)&neigh->primary_key;
677 addr_type = ipv6_addr_type(addr6);
678
679 if (addr_type == IPV6_ADDR_ANY) {
680 addr6 = &ipv6_hdr(skb)->daddr;
681 addr_type = ipv6_addr_type(addr6);
682 }
683
684 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
685 do_tx_error_icmp = true;
686 else {
687 do_tx_error_icmp = false;
688 dst = addr6->s6_addr32[3];
689 }
690 neigh_release(neigh);
691 if (do_tx_error_icmp)
692 goto tx_error_icmp;
693 }
694 #endif
695 else
696 goto tx_error;
697
698 connected = false;
699 }
700
701 tos = tnl_params->tos;
702 if (tos & 0x1) {
703 tos &= ~0x1;
704 if (skb->protocol == htons(ETH_P_IP)) {
705 tos = inner_iph->tos;
706 connected = false;
707 } else if (skb->protocol == htons(ETH_P_IPV6)) {
708 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
709 connected = false;
710 }
711 }
712
713 init_tunnel_flow(&fl4, protocol, dst, tnl_params->saddr,
714 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link,
715 tunnel->fwmark);
716
717 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0)
718 goto tx_error;
719
720 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr) :
721 NULL;
722
723 if (!rt) {
724 rt = ip_route_output_key(tunnel->net, &fl4);
725
726 if (IS_ERR(rt)) {
727 dev->stats.tx_carrier_errors++;
728 goto tx_error;
729 }
730 if (connected)
731 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst,
732 fl4.saddr);
733 }
734
735 if (rt->dst.dev == dev) {
736 ip_rt_put(rt);
737 dev->stats.collisions++;
738 goto tx_error;
739 }
740
741 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) {
742 ip_rt_put(rt);
743 goto tx_error;
744 }
745
746 if (tunnel->err_count > 0) {
747 if (time_before(jiffies,
748 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
749 tunnel->err_count--;
750
751 dst_link_failure(skb);
752 } else
753 tunnel->err_count = 0;
754 }
755
756 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
757 ttl = tnl_params->ttl;
758 if (ttl == 0) {
759 if (skb->protocol == htons(ETH_P_IP))
760 ttl = inner_iph->ttl;
761 #if IS_ENABLED(CONFIG_IPV6)
762 else if (skb->protocol == htons(ETH_P_IPV6))
763 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
764 #endif
765 else
766 ttl = ip4_dst_hoplimit(&rt->dst);
767 }
768
769 df = tnl_params->frag_off;
770 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df)
771 df |= (inner_iph->frag_off&htons(IP_DF));
772
773 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
774 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap);
775 if (max_headroom > dev->needed_headroom)
776 dev->needed_headroom = max_headroom;
777
778 if (skb_cow_head(skb, dev->needed_headroom)) {
779 ip_rt_put(rt);
780 dev->stats.tx_dropped++;
781 kfree_skb(skb);
782 return;
783 }
784
785 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
786 df, !net_eq(tunnel->net, dev_net(dev)));
787 return;
788
789 #if IS_ENABLED(CONFIG_IPV6)
790 tx_error_icmp:
791 dst_link_failure(skb);
792 #endif
793 tx_error:
794 dev->stats.tx_errors++;
795 kfree_skb(skb);
796 }
797 EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
798
799 static void ip_tunnel_update(struct ip_tunnel_net *itn,
800 struct ip_tunnel *t,
801 struct net_device *dev,
802 struct ip_tunnel_parm *p,
803 bool set_mtu,
804 __u32 fwmark)
805 {
806 ip_tunnel_del(itn, t);
807 t->parms.iph.saddr = p->iph.saddr;
808 t->parms.iph.daddr = p->iph.daddr;
809 t->parms.i_key = p->i_key;
810 t->parms.o_key = p->o_key;
811 if (dev->type != ARPHRD_ETHER) {
812 memcpy(dev->dev_addr, &p->iph.saddr, 4);
813 memcpy(dev->broadcast, &p->iph.daddr, 4);
814 }
815 ip_tunnel_add(itn, t);
816
817 t->parms.iph.ttl = p->iph.ttl;
818 t->parms.iph.tos = p->iph.tos;
819 t->parms.iph.frag_off = p->iph.frag_off;
820
821 if (t->parms.link != p->link || t->fwmark != fwmark) {
822 int mtu;
823
824 t->parms.link = p->link;
825 t->fwmark = fwmark;
826 mtu = ip_tunnel_bind_dev(dev);
827 if (set_mtu)
828 dev->mtu = mtu;
829 }
830 dst_cache_reset(&t->dst_cache);
831 netdev_state_change(dev);
832 }
833
834 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
835 {
836 int err = 0;
837 struct ip_tunnel *t = netdev_priv(dev);
838 struct net *net = t->net;
839 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
840
841 BUG_ON(!itn->fb_tunnel_dev);
842 switch (cmd) {
843 case SIOCGETTUNNEL:
844 if (dev == itn->fb_tunnel_dev) {
845 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
846 if (!t)
847 t = netdev_priv(dev);
848 }
849 memcpy(p, &t->parms, sizeof(*p));
850 break;
851
852 case SIOCADDTUNNEL:
853 case SIOCCHGTUNNEL:
854 err = -EPERM;
855 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
856 goto done;
857 if (p->iph.ttl)
858 p->iph.frag_off |= htons(IP_DF);
859 if (!(p->i_flags & VTI_ISVTI)) {
860 if (!(p->i_flags & TUNNEL_KEY))
861 p->i_key = 0;
862 if (!(p->o_flags & TUNNEL_KEY))
863 p->o_key = 0;
864 }
865
866 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
867
868 if (cmd == SIOCADDTUNNEL) {
869 if (!t) {
870 t = ip_tunnel_create(net, itn, p);
871 err = PTR_ERR_OR_ZERO(t);
872 break;
873 }
874
875 err = -EEXIST;
876 break;
877 }
878 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
879 if (t) {
880 if (t->dev != dev) {
881 err = -EEXIST;
882 break;
883 }
884 } else {
885 unsigned int nflags = 0;
886
887 if (ipv4_is_multicast(p->iph.daddr))
888 nflags = IFF_BROADCAST;
889 else if (p->iph.daddr)
890 nflags = IFF_POINTOPOINT;
891
892 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
893 err = -EINVAL;
894 break;
895 }
896
897 t = netdev_priv(dev);
898 }
899 }
900
901 if (t) {
902 err = 0;
903 ip_tunnel_update(itn, t, dev, p, true, 0);
904 } else {
905 err = -ENOENT;
906 }
907 break;
908
909 case SIOCDELTUNNEL:
910 err = -EPERM;
911 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
912 goto done;
913
914 if (dev == itn->fb_tunnel_dev) {
915 err = -ENOENT;
916 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
917 if (!t)
918 goto done;
919 err = -EPERM;
920 if (t == netdev_priv(itn->fb_tunnel_dev))
921 goto done;
922 dev = t->dev;
923 }
924 unregister_netdevice(dev);
925 err = 0;
926 break;
927
928 default:
929 err = -EINVAL;
930 }
931
932 done:
933 return err;
934 }
935 EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);
936
937 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
938 {
939 struct ip_tunnel *tunnel = netdev_priv(dev);
940 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
941 int max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen;
942
943 if (new_mtu < ETH_MIN_MTU)
944 return -EINVAL;
945
946 if (new_mtu > max_mtu) {
947 if (strict)
948 return -EINVAL;
949
950 new_mtu = max_mtu;
951 }
952
953 dev->mtu = new_mtu;
954 return 0;
955 }
956 EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu);
957
958 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
959 {
960 return __ip_tunnel_change_mtu(dev, new_mtu, true);
961 }
962 EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
963
964 static void ip_tunnel_dev_free(struct net_device *dev)
965 {
966 struct ip_tunnel *tunnel = netdev_priv(dev);
967
968 gro_cells_destroy(&tunnel->gro_cells);
969 dst_cache_destroy(&tunnel->dst_cache);
970 free_percpu(dev->tstats);
971 }
972
973 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
974 {
975 struct ip_tunnel *tunnel = netdev_priv(dev);
976 struct ip_tunnel_net *itn;
977
978 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
979
980 if (itn->fb_tunnel_dev != dev) {
981 ip_tunnel_del(itn, netdev_priv(dev));
982 unregister_netdevice_queue(dev, head);
983 }
984 }
985 EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
986
987 struct net *ip_tunnel_get_link_net(const struct net_device *dev)
988 {
989 struct ip_tunnel *tunnel = netdev_priv(dev);
990
991 return tunnel->net;
992 }
993 EXPORT_SYMBOL(ip_tunnel_get_link_net);
994
995 int ip_tunnel_get_iflink(const struct net_device *dev)
996 {
997 struct ip_tunnel *tunnel = netdev_priv(dev);
998
999 return tunnel->parms.link;
1000 }
1001 EXPORT_SYMBOL(ip_tunnel_get_iflink);
1002
1003 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
1004 struct rtnl_link_ops *ops, char *devname)
1005 {
1006 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
1007 struct ip_tunnel_parm parms;
1008 unsigned int i;
1009
1010 for (i = 0; i < IP_TNL_HASH_SIZE; i++)
1011 INIT_HLIST_HEAD(&itn->tunnels[i]);
1012
1013 if (!ops) {
1014 itn->fb_tunnel_dev = NULL;
1015 return 0;
1016 }
1017
1018 memset(&parms, 0, sizeof(parms));
1019 if (devname)
1020 strlcpy(parms.name, devname, IFNAMSIZ);
1021
1022 rtnl_lock();
1023 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
1024 /* FB netdevice is special: we have one, and only one per netns.
1025 * Allowing to move it to another netns is clearly unsafe.
1026 */
1027 if (!IS_ERR(itn->fb_tunnel_dev)) {
1028 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1029 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
1030 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
1031 }
1032 rtnl_unlock();
1033
1034 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
1035 }
1036 EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
1037
1038 static void ip_tunnel_destroy(struct ip_tunnel_net *itn, struct list_head *head,
1039 struct rtnl_link_ops *ops)
1040 {
1041 struct net *net = dev_net(itn->fb_tunnel_dev);
1042 struct net_device *dev, *aux;
1043 int h;
1044
1045 for_each_netdev_safe(net, dev, aux)
1046 if (dev->rtnl_link_ops == ops)
1047 unregister_netdevice_queue(dev, head);
1048
1049 for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
1050 struct ip_tunnel *t;
1051 struct hlist_node *n;
1052 struct hlist_head *thead = &itn->tunnels[h];
1053
1054 hlist_for_each_entry_safe(t, n, thead, hash_node)
1055 /* If dev is in the same netns, it has already
1056 * been added to the list by the previous loop.
1057 */
1058 if (!net_eq(dev_net(t->dev), net))
1059 unregister_netdevice_queue(t->dev, head);
1060 }
1061 }
1062
1063 void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id,
1064 struct rtnl_link_ops *ops)
1065 {
1066 struct ip_tunnel_net *itn;
1067 struct net *net;
1068 LIST_HEAD(list);
1069
1070 rtnl_lock();
1071 list_for_each_entry(net, net_list, exit_list) {
1072 itn = net_generic(net, id);
1073 ip_tunnel_destroy(itn, &list, ops);
1074 }
1075 unregister_netdevice_many(&list);
1076 rtnl_unlock();
1077 }
1078 EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets);
1079
1080 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
1081 struct ip_tunnel_parm *p, __u32 fwmark)
1082 {
1083 struct ip_tunnel *nt;
1084 struct net *net = dev_net(dev);
1085 struct ip_tunnel_net *itn;
1086 int mtu;
1087 int err;
1088
1089 nt = netdev_priv(dev);
1090 itn = net_generic(net, nt->ip_tnl_net_id);
1091
1092 if (nt->collect_md) {
1093 if (rtnl_dereference(itn->collect_md_tun))
1094 return -EEXIST;
1095 } else {
1096 if (ip_tunnel_find(itn, p, dev->type))
1097 return -EEXIST;
1098 }
1099
1100 nt->net = net;
1101 nt->parms = *p;
1102 nt->fwmark = fwmark;
1103 err = register_netdevice(dev);
1104 if (err)
1105 goto out;
1106
1107 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1108 eth_hw_addr_random(dev);
1109
1110 mtu = ip_tunnel_bind_dev(dev);
1111 if (!tb[IFLA_MTU])
1112 dev->mtu = mtu;
1113
1114 ip_tunnel_add(itn, nt);
1115 out:
1116 return err;
1117 }
1118 EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
1119
1120 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
1121 struct ip_tunnel_parm *p, __u32 fwmark)
1122 {
1123 struct ip_tunnel *t;
1124 struct ip_tunnel *tunnel = netdev_priv(dev);
1125 struct net *net = tunnel->net;
1126 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
1127
1128 if (dev == itn->fb_tunnel_dev)
1129 return -EINVAL;
1130
1131 t = ip_tunnel_find(itn, p, dev->type);
1132
1133 if (t) {
1134 if (t->dev != dev)
1135 return -EEXIST;
1136 } else {
1137 t = tunnel;
1138
1139 if (dev->type != ARPHRD_ETHER) {
1140 unsigned int nflags = 0;
1141
1142 if (ipv4_is_multicast(p->iph.daddr))
1143 nflags = IFF_BROADCAST;
1144 else if (p->iph.daddr)
1145 nflags = IFF_POINTOPOINT;
1146
1147 if ((dev->flags ^ nflags) &
1148 (IFF_POINTOPOINT | IFF_BROADCAST))
1149 return -EINVAL;
1150 }
1151 }
1152
1153 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark);
1154 return 0;
1155 }
1156 EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1157
1158 int ip_tunnel_init(struct net_device *dev)
1159 {
1160 struct ip_tunnel *tunnel = netdev_priv(dev);
1161 struct iphdr *iph = &tunnel->parms.iph;
1162 int err;
1163
1164 dev->needs_free_netdev = true;
1165 dev->priv_destructor = ip_tunnel_dev_free;
1166 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1167 if (!dev->tstats)
1168 return -ENOMEM;
1169
1170 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1171 if (err) {
1172 free_percpu(dev->tstats);
1173 return err;
1174 }
1175
1176 err = gro_cells_init(&tunnel->gro_cells, dev);
1177 if (err) {
1178 dst_cache_destroy(&tunnel->dst_cache);
1179 free_percpu(dev->tstats);
1180 return err;
1181 }
1182
1183 tunnel->dev = dev;
1184 tunnel->net = dev_net(dev);
1185 strcpy(tunnel->parms.name, dev->name);
1186 iph->version = 4;
1187 iph->ihl = 5;
1188
1189 if (tunnel->collect_md) {
1190 dev->features |= NETIF_F_NETNS_LOCAL;
1191 netif_keep_dst(dev);
1192 }
1193 return 0;
1194 }
1195 EXPORT_SYMBOL_GPL(ip_tunnel_init);
1196
1197 void ip_tunnel_uninit(struct net_device *dev)
1198 {
1199 struct ip_tunnel *tunnel = netdev_priv(dev);
1200 struct net *net = tunnel->net;
1201 struct ip_tunnel_net *itn;
1202
1203 itn = net_generic(net, tunnel->ip_tnl_net_id);
1204 /* fb_tunnel_dev will be unregisted in net-exit call. */
1205 if (itn->fb_tunnel_dev != dev)
1206 ip_tunnel_del(itn, netdev_priv(dev));
1207
1208 dst_cache_reset(&tunnel->dst_cache);
1209 }
1210 EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1211
1212 /* Do least required initialization, rest of init is done in tunnel_init call */
1213 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id)
1214 {
1215 struct ip_tunnel *tunnel = netdev_priv(dev);
1216 tunnel->ip_tnl_net_id = net_id;
1217 }
1218 EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1219
1220 MODULE_LICENSE("GPL");
CRIS linux kernel tree