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libnvdimm, pfn: make 'resource' attribute only readable by root
[linux-2.6/btrfs-unstable.git] / net / ipv4 / ip_tunnel.c
blobe9805ad664ac24c3405ad015cfaab89dc1c95279
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 < 68)
353 mtu = 68;
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 if (skb_dst(skb))
524 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
525
526 if (skb->protocol == htons(ETH_P_IP)) {
527 if (!skb_is_gso(skb) &&
528 (inner_iph->frag_off & htons(IP_DF)) &&
529 mtu < pkt_size) {
530 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
531 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
532 return -E2BIG;
533 }
534 }
535 #if IS_ENABLED(CONFIG_IPV6)
536 else if (skb->protocol == htons(ETH_P_IPV6)) {
537 struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
538
539 if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
540 mtu >= IPV6_MIN_MTU) {
541 if ((tunnel->parms.iph.daddr &&
542 !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
543 rt6->rt6i_dst.plen == 128) {
544 rt6->rt6i_flags |= RTF_MODIFIED;
545 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
546 }
547 }
548
549 if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU &&
550 mtu < pkt_size) {
551 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
552 return -E2BIG;
553 }
554 }
555 #endif
556 return 0;
557 }
558
559 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
560 {
561 struct ip_tunnel *tunnel = netdev_priv(dev);
562 u32 headroom = sizeof(struct iphdr);
563 struct ip_tunnel_info *tun_info;
564 const struct ip_tunnel_key *key;
565 const struct iphdr *inner_iph;
566 struct rtable *rt;
567 struct flowi4 fl4;
568 __be16 df = 0;
569 u8 tos, ttl;
570
571 tun_info = skb_tunnel_info(skb);
572 if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
573 ip_tunnel_info_af(tun_info) != AF_INET))
574 goto tx_error;
575 key = &tun_info->key;
576 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
577 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
578 tos = key->tos;
579 if (tos == 1) {
580 if (skb->protocol == htons(ETH_P_IP))
581 tos = inner_iph->tos;
582 else if (skb->protocol == htons(ETH_P_IPV6))
583 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
584 }
585 init_tunnel_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 0,
586 RT_TOS(tos), tunnel->parms.link, tunnel->fwmark);
587 if (tunnel->encap.type != TUNNEL_ENCAP_NONE)
588 goto tx_error;
589 rt = ip_route_output_key(tunnel->net, &fl4);
590 if (IS_ERR(rt)) {
591 dev->stats.tx_carrier_errors++;
592 goto tx_error;
593 }
594 if (rt->dst.dev == dev) {
595 ip_rt_put(rt);
596 dev->stats.collisions++;
597 goto tx_error;
598 }
599 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
600 ttl = key->ttl;
601 if (ttl == 0) {
602 if (skb->protocol == htons(ETH_P_IP))
603 ttl = inner_iph->ttl;
604 else if (skb->protocol == htons(ETH_P_IPV6))
605 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
606 else
607 ttl = ip4_dst_hoplimit(&rt->dst);
608 }
609 if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
610 df = htons(IP_DF);
611 else if (skb->protocol == htons(ETH_P_IP))
612 df = inner_iph->frag_off & htons(IP_DF);
613 headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
614 if (headroom > dev->needed_headroom)
615 dev->needed_headroom = headroom;
616
617 if (skb_cow_head(skb, dev->needed_headroom)) {
618 ip_rt_put(rt);
619 goto tx_dropped;
620 }
621 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl,
622 df, !net_eq(tunnel->net, dev_net(dev)));
623 return;
624 tx_error:
625 dev->stats.tx_errors++;
626 goto kfree;
627 tx_dropped:
628 dev->stats.tx_dropped++;
629 kfree:
630 kfree_skb(skb);
631 }
632 EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
633
634 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
635 const struct iphdr *tnl_params, u8 protocol)
636 {
637 struct ip_tunnel *tunnel = netdev_priv(dev);
638 const struct iphdr *inner_iph;
639 struct flowi4 fl4;
640 u8 tos, ttl;
641 __be16 df;
642 struct rtable *rt; /* Route to the other host */
643 unsigned int max_headroom; /* The extra header space needed */
644 __be32 dst;
645 bool connected;
646
647 inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
648 connected = (tunnel->parms.iph.daddr != 0);
649
650 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
651
652 dst = tnl_params->daddr;
653 if (dst == 0) {
654 /* NBMA tunnel */
655
656 if (!skb_dst(skb)) {
657 dev->stats.tx_fifo_errors++;
658 goto tx_error;
659 }
660
661 if (skb->protocol == htons(ETH_P_IP)) {
662 rt = skb_rtable(skb);
663 dst = rt_nexthop(rt, inner_iph->daddr);
664 }
665 #if IS_ENABLED(CONFIG_IPV6)
666 else if (skb->protocol == htons(ETH_P_IPV6)) {
667 const struct in6_addr *addr6;
668 struct neighbour *neigh;
669 bool do_tx_error_icmp;
670 int addr_type;
671
672 neigh = dst_neigh_lookup(skb_dst(skb),
673 &ipv6_hdr(skb)->daddr);
674 if (!neigh)
675 goto tx_error;
676
677 addr6 = (const struct in6_addr *)&neigh->primary_key;
678 addr_type = ipv6_addr_type(addr6);
679
680 if (addr_type == IPV6_ADDR_ANY) {
681 addr6 = &ipv6_hdr(skb)->daddr;
682 addr_type = ipv6_addr_type(addr6);
683 }
684
685 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
686 do_tx_error_icmp = true;
687 else {
688 do_tx_error_icmp = false;
689 dst = addr6->s6_addr32[3];
690 }
691 neigh_release(neigh);
692 if (do_tx_error_icmp)
693 goto tx_error_icmp;
694 }
695 #endif
696 else
697 goto tx_error;
698
699 connected = false;
700 }
701
702 tos = tnl_params->tos;
703 if (tos & 0x1) {
704 tos &= ~0x1;
705 if (skb->protocol == htons(ETH_P_IP)) {
706 tos = inner_iph->tos;
707 connected = false;
708 } else if (skb->protocol == htons(ETH_P_IPV6)) {
709 tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
710 connected = false;
711 }
712 }
713
714 init_tunnel_flow(&fl4, protocol, dst, tnl_params->saddr,
715 tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link,
716 tunnel->fwmark);
717
718 if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0)
719 goto tx_error;
720
721 rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, &fl4.saddr) :
722 NULL;
723
724 if (!rt) {
725 rt = ip_route_output_key(tunnel->net, &fl4);
726
727 if (IS_ERR(rt)) {
728 dev->stats.tx_carrier_errors++;
729 goto tx_error;
730 }
731 if (connected)
732 dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst,
733 fl4.saddr);
734 }
735
736 if (rt->dst.dev == dev) {
737 ip_rt_put(rt);
738 dev->stats.collisions++;
739 goto tx_error;
740 }
741
742 if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) {
743 ip_rt_put(rt);
744 goto tx_error;
745 }
746
747 if (tunnel->err_count > 0) {
748 if (time_before(jiffies,
749 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
750 tunnel->err_count--;
751
752 dst_link_failure(skb);
753 } else
754 tunnel->err_count = 0;
755 }
756
757 tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
758 ttl = tnl_params->ttl;
759 if (ttl == 0) {
760 if (skb->protocol == htons(ETH_P_IP))
761 ttl = inner_iph->ttl;
762 #if IS_ENABLED(CONFIG_IPV6)
763 else if (skb->protocol == htons(ETH_P_IPV6))
764 ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
765 #endif
766 else
767 ttl = ip4_dst_hoplimit(&rt->dst);
768 }
769
770 df = tnl_params->frag_off;
771 if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df)
772 df |= (inner_iph->frag_off&htons(IP_DF));
773
774 max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
775 + rt->dst.header_len + ip_encap_hlen(&tunnel->encap);
776 if (max_headroom > dev->needed_headroom)
777 dev->needed_headroom = max_headroom;
778
779 if (skb_cow_head(skb, dev->needed_headroom)) {
780 ip_rt_put(rt);
781 dev->stats.tx_dropped++;
782 kfree_skb(skb);
783 return;
784 }
785
786 iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
787 df, !net_eq(tunnel->net, dev_net(dev)));
788 return;
789
790 #if IS_ENABLED(CONFIG_IPV6)
791 tx_error_icmp:
792 dst_link_failure(skb);
793 #endif
794 tx_error:
795 dev->stats.tx_errors++;
796 kfree_skb(skb);
797 }
798 EXPORT_SYMBOL_GPL(ip_tunnel_xmit);
799
800 static void ip_tunnel_update(struct ip_tunnel_net *itn,
801 struct ip_tunnel *t,
802 struct net_device *dev,
803 struct ip_tunnel_parm *p,
804 bool set_mtu,
805 __u32 fwmark)
806 {
807 ip_tunnel_del(itn, t);
808 t->parms.iph.saddr = p->iph.saddr;
809 t->parms.iph.daddr = p->iph.daddr;
810 t->parms.i_key = p->i_key;
811 t->parms.o_key = p->o_key;
812 if (dev->type != ARPHRD_ETHER) {
813 memcpy(dev->dev_addr, &p->iph.saddr, 4);
814 memcpy(dev->broadcast, &p->iph.daddr, 4);
815 }
816 ip_tunnel_add(itn, t);
817
818 t->parms.iph.ttl = p->iph.ttl;
819 t->parms.iph.tos = p->iph.tos;
820 t->parms.iph.frag_off = p->iph.frag_off;
821
822 if (t->parms.link != p->link || t->fwmark != fwmark) {
823 int mtu;
824
825 t->parms.link = p->link;
826 t->fwmark = fwmark;
827 mtu = ip_tunnel_bind_dev(dev);
828 if (set_mtu)
829 dev->mtu = mtu;
830 }
831 dst_cache_reset(&t->dst_cache);
832 netdev_state_change(dev);
833 }
834
835 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
836 {
837 int err = 0;
838 struct ip_tunnel *t = netdev_priv(dev);
839 struct net *net = t->net;
840 struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id);
841
842 BUG_ON(!itn->fb_tunnel_dev);
843 switch (cmd) {
844 case SIOCGETTUNNEL:
845 if (dev == itn->fb_tunnel_dev) {
846 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
847 if (!t)
848 t = netdev_priv(dev);
849 }
850 memcpy(p, &t->parms, sizeof(*p));
851 break;
852
853 case SIOCADDTUNNEL:
854 case SIOCCHGTUNNEL:
855 err = -EPERM;
856 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
857 goto done;
858 if (p->iph.ttl)
859 p->iph.frag_off |= htons(IP_DF);
860 if (!(p->i_flags & VTI_ISVTI)) {
861 if (!(p->i_flags & TUNNEL_KEY))
862 p->i_key = 0;
863 if (!(p->o_flags & TUNNEL_KEY))
864 p->o_key = 0;
865 }
866
867 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
868
869 if (cmd == SIOCADDTUNNEL) {
870 if (!t) {
871 t = ip_tunnel_create(net, itn, p);
872 err = PTR_ERR_OR_ZERO(t);
873 break;
874 }
875
876 err = -EEXIST;
877 break;
878 }
879 if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
880 if (t) {
881 if (t->dev != dev) {
882 err = -EEXIST;
883 break;
884 }
885 } else {
886 unsigned int nflags = 0;
887
888 if (ipv4_is_multicast(p->iph.daddr))
889 nflags = IFF_BROADCAST;
890 else if (p->iph.daddr)
891 nflags = IFF_POINTOPOINT;
892
893 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
894 err = -EINVAL;
895 break;
896 }
897
898 t = netdev_priv(dev);
899 }
900 }
901
902 if (t) {
903 err = 0;
904 ip_tunnel_update(itn, t, dev, p, true, 0);
905 } else {
906 err = -ENOENT;
907 }
908 break;
909
910 case SIOCDELTUNNEL:
911 err = -EPERM;
912 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
913 goto done;
914
915 if (dev == itn->fb_tunnel_dev) {
916 err = -ENOENT;
917 t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type);
918 if (!t)
919 goto done;
920 err = -EPERM;
921 if (t == netdev_priv(itn->fb_tunnel_dev))
922 goto done;
923 dev = t->dev;
924 }
925 unregister_netdevice(dev);
926 err = 0;
927 break;
928
929 default:
930 err = -EINVAL;
931 }
932
933 done:
934 return err;
935 }
936 EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);
937
938 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
939 {
940 struct ip_tunnel *tunnel = netdev_priv(dev);
941 int t_hlen = tunnel->hlen + sizeof(struct iphdr);
942 int max_mtu = 0xFFF8 - dev->hard_header_len - t_hlen;
943
944 if (new_mtu < ETH_MIN_MTU)
945 return -EINVAL;
946
947 if (new_mtu > max_mtu) {
948 if (strict)
949 return -EINVAL;
950
951 new_mtu = max_mtu;
952 }
953
954 dev->mtu = new_mtu;
955 return 0;
956 }
957 EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu);
958
959 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
960 {
961 return __ip_tunnel_change_mtu(dev, new_mtu, true);
962 }
963 EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu);
964
965 static void ip_tunnel_dev_free(struct net_device *dev)
966 {
967 struct ip_tunnel *tunnel = netdev_priv(dev);
968
969 gro_cells_destroy(&tunnel->gro_cells);
970 dst_cache_destroy(&tunnel->dst_cache);
971 free_percpu(dev->tstats);
972 }
973
974 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head)
975 {
976 struct ip_tunnel *tunnel = netdev_priv(dev);
977 struct ip_tunnel_net *itn;
978
979 itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id);
980
981 if (itn->fb_tunnel_dev != dev) {
982 ip_tunnel_del(itn, netdev_priv(dev));
983 unregister_netdevice_queue(dev, head);
984 }
985 }
986 EXPORT_SYMBOL_GPL(ip_tunnel_dellink);
987
988 struct net *ip_tunnel_get_link_net(const struct net_device *dev)
989 {
990 struct ip_tunnel *tunnel = netdev_priv(dev);
991
992 return tunnel->net;
993 }
994 EXPORT_SYMBOL(ip_tunnel_get_link_net);
995
996 int ip_tunnel_get_iflink(const struct net_device *dev)
997 {
998 struct ip_tunnel *tunnel = netdev_priv(dev);
999
1000 return tunnel->parms.link;
1001 }
1002 EXPORT_SYMBOL(ip_tunnel_get_iflink);
1003
1004 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
1005 struct rtnl_link_ops *ops, char *devname)
1006 {
1007 struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id);
1008 struct ip_tunnel_parm parms;
1009 unsigned int i;
1010
1011 for (i = 0; i < IP_TNL_HASH_SIZE; i++)
1012 INIT_HLIST_HEAD(&itn->tunnels[i]);
1013
1014 if (!ops) {
1015 itn->fb_tunnel_dev = NULL;
1016 return 0;
1017 }
1018
1019 memset(&parms, 0, sizeof(parms));
1020 if (devname)
1021 strlcpy(parms.name, devname, IFNAMSIZ);
1022
1023 rtnl_lock();
1024 itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms);
1025 /* FB netdevice is special: we have one, and only one per netns.
1026 * Allowing to move it to another netns is clearly unsafe.
1027 */
1028 if (!IS_ERR(itn->fb_tunnel_dev)) {
1029 itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1030 itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev);
1031 ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev));
1032 }
1033 rtnl_unlock();
1034
1035 return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev);
1036 }
1037 EXPORT_SYMBOL_GPL(ip_tunnel_init_net);
1038
1039 static void ip_tunnel_destroy(struct ip_tunnel_net *itn, struct list_head *head,
1040 struct rtnl_link_ops *ops)
1041 {
1042 struct net *net = dev_net(itn->fb_tunnel_dev);
1043 struct net_device *dev, *aux;
1044 int h;
1045
1046 for_each_netdev_safe(net, dev, aux)
1047 if (dev->rtnl_link_ops == ops)
1048 unregister_netdevice_queue(dev, head);
1049
1050 for (h = 0; h < IP_TNL_HASH_SIZE; h++) {
1051 struct ip_tunnel *t;
1052 struct hlist_node *n;
1053 struct hlist_head *thead = &itn->tunnels[h];
1054
1055 hlist_for_each_entry_safe(t, n, thead, hash_node)
1056 /* If dev is in the same netns, it has already
1057 * been added to the list by the previous loop.
1058 */
1059 if (!net_eq(dev_net(t->dev), net))
1060 unregister_netdevice_queue(t->dev, head);
1061 }
1062 }
1063
1064 void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops)
1065 {
1066 LIST_HEAD(list);
1067
1068 rtnl_lock();
1069 ip_tunnel_destroy(itn, &list, ops);
1070 unregister_netdevice_many(&list);
1071 rtnl_unlock();
1072 }
1073 EXPORT_SYMBOL_GPL(ip_tunnel_delete_net);
1074
1075 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
1076 struct ip_tunnel_parm *p, __u32 fwmark)
1077 {
1078 struct ip_tunnel *nt;
1079 struct net *net = dev_net(dev);
1080 struct ip_tunnel_net *itn;
1081 int mtu;
1082 int err;
1083
1084 nt = netdev_priv(dev);
1085 itn = net_generic(net, nt->ip_tnl_net_id);
1086
1087 if (nt->collect_md) {
1088 if (rtnl_dereference(itn->collect_md_tun))
1089 return -EEXIST;
1090 } else {
1091 if (ip_tunnel_find(itn, p, dev->type))
1092 return -EEXIST;
1093 }
1094
1095 nt->net = net;
1096 nt->parms = *p;
1097 nt->fwmark = fwmark;
1098 err = register_netdevice(dev);
1099 if (err)
1100 goto out;
1101
1102 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1103 eth_hw_addr_random(dev);
1104
1105 mtu = ip_tunnel_bind_dev(dev);
1106 if (!tb[IFLA_MTU])
1107 dev->mtu = mtu;
1108
1109 ip_tunnel_add(itn, nt);
1110 out:
1111 return err;
1112 }
1113 EXPORT_SYMBOL_GPL(ip_tunnel_newlink);
1114
1115 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
1116 struct ip_tunnel_parm *p, __u32 fwmark)
1117 {
1118 struct ip_tunnel *t;
1119 struct ip_tunnel *tunnel = netdev_priv(dev);
1120 struct net *net = tunnel->net;
1121 struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id);
1122
1123 if (dev == itn->fb_tunnel_dev)
1124 return -EINVAL;
1125
1126 t = ip_tunnel_find(itn, p, dev->type);
1127
1128 if (t) {
1129 if (t->dev != dev)
1130 return -EEXIST;
1131 } else {
1132 t = tunnel;
1133
1134 if (dev->type != ARPHRD_ETHER) {
1135 unsigned int nflags = 0;
1136
1137 if (ipv4_is_multicast(p->iph.daddr))
1138 nflags = IFF_BROADCAST;
1139 else if (p->iph.daddr)
1140 nflags = IFF_POINTOPOINT;
1141
1142 if ((dev->flags ^ nflags) &
1143 (IFF_POINTOPOINT | IFF_BROADCAST))
1144 return -EINVAL;
1145 }
1146 }
1147
1148 ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark);
1149 return 0;
1150 }
1151 EXPORT_SYMBOL_GPL(ip_tunnel_changelink);
1152
1153 int ip_tunnel_init(struct net_device *dev)
1154 {
1155 struct ip_tunnel *tunnel = netdev_priv(dev);
1156 struct iphdr *iph = &tunnel->parms.iph;
1157 int err;
1158
1159 dev->needs_free_netdev = true;
1160 dev->priv_destructor = ip_tunnel_dev_free;
1161 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1162 if (!dev->tstats)
1163 return -ENOMEM;
1164
1165 err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1166 if (err) {
1167 free_percpu(dev->tstats);
1168 return err;
1169 }
1170
1171 err = gro_cells_init(&tunnel->gro_cells, dev);
1172 if (err) {
1173 dst_cache_destroy(&tunnel->dst_cache);
1174 free_percpu(dev->tstats);
1175 return err;
1176 }
1177
1178 tunnel->dev = dev;
1179 tunnel->net = dev_net(dev);
1180 strcpy(tunnel->parms.name, dev->name);
1181 iph->version = 4;
1182 iph->ihl = 5;
1183
1184 if (tunnel->collect_md) {
1185 dev->features |= NETIF_F_NETNS_LOCAL;
1186 netif_keep_dst(dev);
1187 }
1188 return 0;
1189 }
1190 EXPORT_SYMBOL_GPL(ip_tunnel_init);
1191
1192 void ip_tunnel_uninit(struct net_device *dev)
1193 {
1194 struct ip_tunnel *tunnel = netdev_priv(dev);
1195 struct net *net = tunnel->net;
1196 struct ip_tunnel_net *itn;
1197
1198 itn = net_generic(net, tunnel->ip_tnl_net_id);
1199 /* fb_tunnel_dev will be unregisted in net-exit call. */
1200 if (itn->fb_tunnel_dev != dev)
1201 ip_tunnel_del(itn, netdev_priv(dev));
1202
1203 dst_cache_reset(&tunnel->dst_cache);
1204 }
1205 EXPORT_SYMBOL_GPL(ip_tunnel_uninit);
1206
1207 /* Do least required initialization, rest of init is done in tunnel_init call */
1208 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id)
1209 {
1210 struct ip_tunnel *tunnel = netdev_priv(dev);
1211 tunnel->ip_tnl_net_id = net_id;
1212 }
1213 EXPORT_SYMBOL_GPL(ip_tunnel_setup);
1214
1215 MODULE_LICENSE("GPL");
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