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xfrm: Check for esn buffer len in xfrm_new_ae
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv4 / ip_gre.c
blobda5941f18c3c1063ed1477578931e045c8dd7b90
1 /*
2 * Linux NET3: GRE over IP protocol decoder.
3 *
4 * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 */
12
13 #include <linux/capability.h>
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <asm/uaccess.h>
19 #include <linux/skbuff.h>
20 #include <linux/netdevice.h>
21 #include <linux/in.h>
22 #include <linux/tcp.h>
23 #include <linux/udp.h>
24 #include <linux/if_arp.h>
25 #include <linux/mroute.h>
26 #include <linux/init.h>
27 #include <linux/in6.h>
28 #include <linux/inetdevice.h>
29 #include <linux/igmp.h>
30 #include <linux/netfilter_ipv4.h>
31 #include <linux/etherdevice.h>
32 #include <linux/if_ether.h>
33
34 #include <net/sock.h>
35 #include <net/ip.h>
36 #include <net/icmp.h>
37 #include <net/protocol.h>
38 #include <net/ipip.h>
39 #include <net/arp.h>
40 #include <net/checksum.h>
41 #include <net/dsfield.h>
42 #include <net/inet_ecn.h>
43 #include <net/xfrm.h>
44 #include <net/net_namespace.h>
45 #include <net/netns/generic.h>
46 #include <net/rtnetlink.h>
47 #include <net/gre.h>
48
49 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
50 #include <net/ipv6.h>
51 #include <net/ip6_fib.h>
52 #include <net/ip6_route.h>
53 #endif
54
55 /*
56 Problems & solutions
57 --------------------
58
59 1. The most important issue is detecting local dead loops.
60 They would cause complete host lockup in transmit, which
61 would be "resolved" by stack overflow or, if queueing is enabled,
62 with infinite looping in net_bh.
63
64 We cannot track such dead loops during route installation,
65 it is infeasible task. The most general solutions would be
66 to keep skb->encapsulation counter (sort of local ttl),
67 and silently drop packet when it expires. It is a good
68 solution, but it supposes maintaing new variable in ALL
69 skb, even if no tunneling is used.
70
71 Current solution: xmit_recursion breaks dead loops. This is a percpu
72 counter, since when we enter the first ndo_xmit(), cpu migration is
73 forbidden. We force an exit if this counter reaches RECURSION_LIMIT
74
75 2. Networking dead loops would not kill routers, but would really
76 kill network. IP hop limit plays role of "t->recursion" in this case,
77 if we copy it from packet being encapsulated to upper header.
78 It is very good solution, but it introduces two problems:
79
80 - Routing protocols, using packets with ttl=1 (OSPF, RIP2),
81 do not work over tunnels.
82 - traceroute does not work. I planned to relay ICMP from tunnel,
83 so that this problem would be solved and traceroute output
84 would even more informative. This idea appeared to be wrong:
85 only Linux complies to rfc1812 now (yes, guys, Linux is the only
86 true router now :-)), all routers (at least, in neighbourhood of mine)
87 return only 8 bytes of payload. It is the end.
88
89 Hence, if we want that OSPF worked or traceroute said something reasonable,
90 we should search for another solution.
91
92 One of them is to parse packet trying to detect inner encapsulation
93 made by our node. It is difficult or even impossible, especially,
94 taking into account fragmentation. TO be short, tt is not solution at all.
95
96 Current solution: The solution was UNEXPECTEDLY SIMPLE.
97 We force DF flag on tunnels with preconfigured hop limit,
98 that is ALL. :-) Well, it does not remove the problem completely,
99 but exponential growth of network traffic is changed to linear
100 (branches, that exceed pmtu are pruned) and tunnel mtu
101 fastly degrades to value <68, where looping stops.
102 Yes, it is not good if there exists a router in the loop,
103 which does not force DF, even when encapsulating packets have DF set.
104 But it is not our problem! Nobody could accuse us, we made
105 all that we could make. Even if it is your gated who injected
106 fatal route to network, even if it were you who configured
107 fatal static route: you are innocent. :-)
108
109
110
111 3. Really, ipv4/ipip.c, ipv4/ip_gre.c and ipv6/sit.c contain
112 practically identical code. It would be good to glue them
113 together, but it is not very evident, how to make them modular.
114 sit is integral part of IPv6, ipip and gre are naturally modular.
115 We could extract common parts (hash table, ioctl etc)
116 to a separate module (ip_tunnel.c).
117
118 Alexey Kuznetsov.
119 */
120
121 static struct rtnl_link_ops ipgre_link_ops __read_mostly;
122 static int ipgre_tunnel_init(struct net_device *dev);
123 static void ipgre_tunnel_setup(struct net_device *dev);
124 static int ipgre_tunnel_bind_dev(struct net_device *dev);
125
126 /* Fallback tunnel: no source, no destination, no key, no options */
127
128 #define HASH_SIZE 16
129
130 static int ipgre_net_id __read_mostly;
131 struct ipgre_net {
132 struct ip_tunnel __rcu *tunnels[4][HASH_SIZE];
133
134 struct net_device *fb_tunnel_dev;
135 };
136
137 /* Tunnel hash table */
138
139 /*
140 4 hash tables:
141
142 3: (remote,local)
143 2: (remote,*)
144 1: (*,local)
145 0: (*,*)
146
147 We require exact key match i.e. if a key is present in packet
148 it will match only tunnel with the same key; if it is not present,
149 it will match only keyless tunnel.
150
151 All keysless packets, if not matched configured keyless tunnels
152 will match fallback tunnel.
153 */
154
155 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
156
157 #define tunnels_r_l tunnels[3]
158 #define tunnels_r tunnels[2]
159 #define tunnels_l tunnels[1]
160 #define tunnels_wc tunnels[0]
161 /*
162 * Locking : hash tables are protected by RCU and RTNL
163 */
164
165 #define for_each_ip_tunnel_rcu(start) \
166 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
167
168 /* often modified stats are per cpu, other are shared (netdev->stats) */
169 struct pcpu_tstats {
170 unsigned long rx_packets;
171 unsigned long rx_bytes;
172 unsigned long tx_packets;
173 unsigned long tx_bytes;
174 };
175
176 static struct net_device_stats *ipgre_get_stats(struct net_device *dev)
177 {
178 struct pcpu_tstats sum = { 0 };
179 int i;
180
181 for_each_possible_cpu(i) {
182 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
183
184 sum.rx_packets += tstats->rx_packets;
185 sum.rx_bytes += tstats->rx_bytes;
186 sum.tx_packets += tstats->tx_packets;
187 sum.tx_bytes += tstats->tx_bytes;
188 }
189 dev->stats.rx_packets = sum.rx_packets;
190 dev->stats.rx_bytes = sum.rx_bytes;
191 dev->stats.tx_packets = sum.tx_packets;
192 dev->stats.tx_bytes = sum.tx_bytes;
193 return &dev->stats;
194 }
195
196 /* Given src, dst and key, find appropriate for input tunnel. */
197
198 static struct ip_tunnel * ipgre_tunnel_lookup(struct net_device *dev,
199 __be32 remote, __be32 local,
200 __be32 key, __be16 gre_proto)
201 {
202 struct net *net = dev_net(dev);
203 int link = dev->ifindex;
204 unsigned int h0 = HASH(remote);
205 unsigned int h1 = HASH(key);
206 struct ip_tunnel *t, *cand = NULL;
207 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
208 int dev_type = (gre_proto == htons(ETH_P_TEB)) ?
209 ARPHRD_ETHER : ARPHRD_IPGRE;
210 int score, cand_score = 4;
211
212 for_each_ip_tunnel_rcu(ign->tunnels_r_l[h0 ^ h1]) {
213 if (local != t->parms.iph.saddr ||
214 remote != t->parms.iph.daddr ||
215 key != t->parms.i_key ||
216 !(t->dev->flags & IFF_UP))
217 continue;
218
219 if (t->dev->type != ARPHRD_IPGRE &&
220 t->dev->type != dev_type)
221 continue;
222
223 score = 0;
224 if (t->parms.link != link)
225 score |= 1;
226 if (t->dev->type != dev_type)
227 score |= 2;
228 if (score == 0)
229 return t;
230
231 if (score < cand_score) {
232 cand = t;
233 cand_score = score;
234 }
235 }
236
237 for_each_ip_tunnel_rcu(ign->tunnels_r[h0 ^ h1]) {
238 if (remote != t->parms.iph.daddr ||
239 key != t->parms.i_key ||
240 !(t->dev->flags & IFF_UP))
241 continue;
242
243 if (t->dev->type != ARPHRD_IPGRE &&
244 t->dev->type != dev_type)
245 continue;
246
247 score = 0;
248 if (t->parms.link != link)
249 score |= 1;
250 if (t->dev->type != dev_type)
251 score |= 2;
252 if (score == 0)
253 return t;
254
255 if (score < cand_score) {
256 cand = t;
257 cand_score = score;
258 }
259 }
260
261 for_each_ip_tunnel_rcu(ign->tunnels_l[h1]) {
262 if ((local != t->parms.iph.saddr &&
263 (local != t->parms.iph.daddr ||
264 !ipv4_is_multicast(local))) ||
265 key != t->parms.i_key ||
266 !(t->dev->flags & IFF_UP))
267 continue;
268
269 if (t->dev->type != ARPHRD_IPGRE &&
270 t->dev->type != dev_type)
271 continue;
272
273 score = 0;
274 if (t->parms.link != link)
275 score |= 1;
276 if (t->dev->type != dev_type)
277 score |= 2;
278 if (score == 0)
279 return t;
280
281 if (score < cand_score) {
282 cand = t;
283 cand_score = score;
284 }
285 }
286
287 for_each_ip_tunnel_rcu(ign->tunnels_wc[h1]) {
288 if (t->parms.i_key != key ||
289 !(t->dev->flags & IFF_UP))
290 continue;
291
292 if (t->dev->type != ARPHRD_IPGRE &&
293 t->dev->type != dev_type)
294 continue;
295
296 score = 0;
297 if (t->parms.link != link)
298 score |= 1;
299 if (t->dev->type != dev_type)
300 score |= 2;
301 if (score == 0)
302 return t;
303
304 if (score < cand_score) {
305 cand = t;
306 cand_score = score;
307 }
308 }
309
310 if (cand != NULL)
311 return cand;
312
313 dev = ign->fb_tunnel_dev;
314 if (dev->flags & IFF_UP)
315 return netdev_priv(dev);
316
317 return NULL;
318 }
319
320 static struct ip_tunnel __rcu **__ipgre_bucket(struct ipgre_net *ign,
321 struct ip_tunnel_parm *parms)
322 {
323 __be32 remote = parms->iph.daddr;
324 __be32 local = parms->iph.saddr;
325 __be32 key = parms->i_key;
326 unsigned int h = HASH(key);
327 int prio = 0;
328
329 if (local)
330 prio |= 1;
331 if (remote && !ipv4_is_multicast(remote)) {
332 prio |= 2;
333 h ^= HASH(remote);
334 }
335
336 return &ign->tunnels[prio][h];
337 }
338
339 static inline struct ip_tunnel __rcu **ipgre_bucket(struct ipgre_net *ign,
340 struct ip_tunnel *t)
341 {
342 return __ipgre_bucket(ign, &t->parms);
343 }
344
345 static void ipgre_tunnel_link(struct ipgre_net *ign, struct ip_tunnel *t)
346 {
347 struct ip_tunnel __rcu **tp = ipgre_bucket(ign, t);
348
349 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
350 rcu_assign_pointer(*tp, t);
351 }
352
353 static void ipgre_tunnel_unlink(struct ipgre_net *ign, struct ip_tunnel *t)
354 {
355 struct ip_tunnel __rcu **tp;
356 struct ip_tunnel *iter;
357
358 for (tp = ipgre_bucket(ign, t);
359 (iter = rtnl_dereference(*tp)) != NULL;
360 tp = &iter->next) {
361 if (t == iter) {
362 rcu_assign_pointer(*tp, t->next);
363 break;
364 }
365 }
366 }
367
368 static struct ip_tunnel *ipgre_tunnel_find(struct net *net,
369 struct ip_tunnel_parm *parms,
370 int type)
371 {
372 __be32 remote = parms->iph.daddr;
373 __be32 local = parms->iph.saddr;
374 __be32 key = parms->i_key;
375 int link = parms->link;
376 struct ip_tunnel *t;
377 struct ip_tunnel __rcu **tp;
378 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
379
380 for (tp = __ipgre_bucket(ign, parms);
381 (t = rtnl_dereference(*tp)) != NULL;
382 tp = &t->next)
383 if (local == t->parms.iph.saddr &&
384 remote == t->parms.iph.daddr &&
385 key == t->parms.i_key &&
386 link == t->parms.link &&
387 type == t->dev->type)
388 break;
389
390 return t;
391 }
392
393 static struct ip_tunnel *ipgre_tunnel_locate(struct net *net,
394 struct ip_tunnel_parm *parms, int create)
395 {
396 struct ip_tunnel *t, *nt;
397 struct net_device *dev;
398 char name[IFNAMSIZ];
399 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
400
401 t = ipgre_tunnel_find(net, parms, ARPHRD_IPGRE);
402 if (t || !create)
403 return t;
404
405 if (parms->name[0])
406 strlcpy(name, parms->name, IFNAMSIZ);
407 else
408 strcpy(name, "gre%d");
409
410 dev = alloc_netdev(sizeof(*t), name, ipgre_tunnel_setup);
411 if (!dev)
412 return NULL;
413
414 dev_net_set(dev, net);
415
416 if (strchr(name, '%')) {
417 if (dev_alloc_name(dev, name) < 0)
418 goto failed_free;
419 }
420
421 nt = netdev_priv(dev);
422 nt->parms = *parms;
423 dev->rtnl_link_ops = &ipgre_link_ops;
424
425 dev->mtu = ipgre_tunnel_bind_dev(dev);
426
427 if (register_netdevice(dev) < 0)
428 goto failed_free;
429
430 dev_hold(dev);
431 ipgre_tunnel_link(ign, nt);
432 return nt;
433
434 failed_free:
435 free_netdev(dev);
436 return NULL;
437 }
438
439 static void ipgre_tunnel_uninit(struct net_device *dev)
440 {
441 struct net *net = dev_net(dev);
442 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
443
444 ipgre_tunnel_unlink(ign, netdev_priv(dev));
445 dev_put(dev);
446 }
447
448
449 static void ipgre_err(struct sk_buff *skb, u32 info)
450 {
451
452 /* All the routers (except for Linux) return only
453 8 bytes of packet payload. It means, that precise relaying of
454 ICMP in the real Internet is absolutely infeasible.
455
456 Moreover, Cisco "wise men" put GRE key to the third word
457 in GRE header. It makes impossible maintaining even soft state for keyed
458 GRE tunnels with enabled checksum. Tell them "thank you".
459
460 Well, I wonder, rfc1812 was written by Cisco employee,
461 what the hell these idiots break standrads established
462 by themself???
463 */
464
465 struct iphdr *iph = (struct iphdr *)skb->data;
466 __be16 *p = (__be16*)(skb->data+(iph->ihl<<2));
467 int grehlen = (iph->ihl<<2) + 4;
468 const int type = icmp_hdr(skb)->type;
469 const int code = icmp_hdr(skb)->code;
470 struct ip_tunnel *t;
471 __be16 flags;
472
473 flags = p[0];
474 if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) {
475 if (flags&(GRE_VERSION|GRE_ROUTING))
476 return;
477 if (flags&GRE_KEY) {
478 grehlen += 4;
479 if (flags&GRE_CSUM)
480 grehlen += 4;
481 }
482 }
483
484 /* If only 8 bytes returned, keyed message will be dropped here */
485 if (skb_headlen(skb) < grehlen)
486 return;
487
488 switch (type) {
489 default:
490 case ICMP_PARAMETERPROB:
491 return;
492
493 case ICMP_DEST_UNREACH:
494 switch (code) {
495 case ICMP_SR_FAILED:
496 case ICMP_PORT_UNREACH:
497 /* Impossible event. */
498 return;
499 case ICMP_FRAG_NEEDED:
500 /* Soft state for pmtu is maintained by IP core. */
501 return;
502 default:
503 /* All others are translated to HOST_UNREACH.
504 rfc2003 contains "deep thoughts" about NET_UNREACH,
505 I believe they are just ether pollution. --ANK
506 */
507 break;
508 }
509 break;
510 case ICMP_TIME_EXCEEDED:
511 if (code != ICMP_EXC_TTL)
512 return;
513 break;
514 }
515
516 rcu_read_lock();
517 t = ipgre_tunnel_lookup(skb->dev, iph->daddr, iph->saddr,
518 flags & GRE_KEY ?
519 *(((__be32 *)p) + (grehlen / 4) - 1) : 0,
520 p[1]);
521 if (t == NULL || t->parms.iph.daddr == 0 ||
522 ipv4_is_multicast(t->parms.iph.daddr))
523 goto out;
524
525 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
526 goto out;
527
528 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
529 t->err_count++;
530 else
531 t->err_count = 1;
532 t->err_time = jiffies;
533 out:
534 rcu_read_unlock();
535 }
536
537 static inline void ipgre_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
538 {
539 if (INET_ECN_is_ce(iph->tos)) {
540 if (skb->protocol == htons(ETH_P_IP)) {
541 IP_ECN_set_ce(ip_hdr(skb));
542 } else if (skb->protocol == htons(ETH_P_IPV6)) {
543 IP6_ECN_set_ce(ipv6_hdr(skb));
544 }
545 }
546 }
547
548 static inline u8
549 ipgre_ecn_encapsulate(u8 tos, struct iphdr *old_iph, struct sk_buff *skb)
550 {
551 u8 inner = 0;
552 if (skb->protocol == htons(ETH_P_IP))
553 inner = old_iph->tos;
554 else if (skb->protocol == htons(ETH_P_IPV6))
555 inner = ipv6_get_dsfield((struct ipv6hdr *)old_iph);
556 return INET_ECN_encapsulate(tos, inner);
557 }
558
559 static int ipgre_rcv(struct sk_buff *skb)
560 {
561 struct iphdr *iph;
562 u8 *h;
563 __be16 flags;
564 __sum16 csum = 0;
565 __be32 key = 0;
566 u32 seqno = 0;
567 struct ip_tunnel *tunnel;
568 int offset = 4;
569 __be16 gre_proto;
570
571 if (!pskb_may_pull(skb, 16))
572 goto drop_nolock;
573
574 iph = ip_hdr(skb);
575 h = skb->data;
576 flags = *(__be16*)h;
577
578 if (flags&(GRE_CSUM|GRE_KEY|GRE_ROUTING|GRE_SEQ|GRE_VERSION)) {
579 /* - Version must be 0.
580 - We do not support routing headers.
581 */
582 if (flags&(GRE_VERSION|GRE_ROUTING))
583 goto drop_nolock;
584
585 if (flags&GRE_CSUM) {
586 switch (skb->ip_summed) {
587 case CHECKSUM_COMPLETE:
588 csum = csum_fold(skb->csum);
589 if (!csum)
590 break;
591 /* fall through */
592 case CHECKSUM_NONE:
593 skb->csum = 0;
594 csum = __skb_checksum_complete(skb);
595 skb->ip_summed = CHECKSUM_COMPLETE;
596 }
597 offset += 4;
598 }
599 if (flags&GRE_KEY) {
600 key = *(__be32*)(h + offset);
601 offset += 4;
602 }
603 if (flags&GRE_SEQ) {
604 seqno = ntohl(*(__be32*)(h + offset));
605 offset += 4;
606 }
607 }
608
609 gre_proto = *(__be16 *)(h + 2);
610
611 rcu_read_lock();
612 if ((tunnel = ipgre_tunnel_lookup(skb->dev,
613 iph->saddr, iph->daddr, key,
614 gre_proto))) {
615 struct pcpu_tstats *tstats;
616
617 secpath_reset(skb);
618
619 skb->protocol = gre_proto;
620 /* WCCP version 1 and 2 protocol decoding.
621 * - Change protocol to IP
622 * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header
623 */
624 if (flags == 0 && gre_proto == htons(ETH_P_WCCP)) {
625 skb->protocol = htons(ETH_P_IP);
626 if ((*(h + offset) & 0xF0) != 0x40)
627 offset += 4;
628 }
629
630 skb->mac_header = skb->network_header;
631 __pskb_pull(skb, offset);
632 skb_postpull_rcsum(skb, skb_transport_header(skb), offset);
633 skb->pkt_type = PACKET_HOST;
634 #ifdef CONFIG_NET_IPGRE_BROADCAST
635 if (ipv4_is_multicast(iph->daddr)) {
636 /* Looped back packet, drop it! */
637 if (rt_is_output_route(skb_rtable(skb)))
638 goto drop;
639 tunnel->dev->stats.multicast++;
640 skb->pkt_type = PACKET_BROADCAST;
641 }
642 #endif
643
644 if (((flags&GRE_CSUM) && csum) ||
645 (!(flags&GRE_CSUM) && tunnel->parms.i_flags&GRE_CSUM)) {
646 tunnel->dev->stats.rx_crc_errors++;
647 tunnel->dev->stats.rx_errors++;
648 goto drop;
649 }
650 if (tunnel->parms.i_flags&GRE_SEQ) {
651 if (!(flags&GRE_SEQ) ||
652 (tunnel->i_seqno && (s32)(seqno - tunnel->i_seqno) < 0)) {
653 tunnel->dev->stats.rx_fifo_errors++;
654 tunnel->dev->stats.rx_errors++;
655 goto drop;
656 }
657 tunnel->i_seqno = seqno + 1;
658 }
659
660 /* Warning: All skb pointers will be invalidated! */
661 if (tunnel->dev->type == ARPHRD_ETHER) {
662 if (!pskb_may_pull(skb, ETH_HLEN)) {
663 tunnel->dev->stats.rx_length_errors++;
664 tunnel->dev->stats.rx_errors++;
665 goto drop;
666 }
667
668 iph = ip_hdr(skb);
669 skb->protocol = eth_type_trans(skb, tunnel->dev);
670 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
671 }
672
673 tstats = this_cpu_ptr(tunnel->dev->tstats);
674 tstats->rx_packets++;
675 tstats->rx_bytes += skb->len;
676
677 __skb_tunnel_rx(skb, tunnel->dev);
678
679 skb_reset_network_header(skb);
680 ipgre_ecn_decapsulate(iph, skb);
681
682 netif_rx(skb);
683
684 rcu_read_unlock();
685 return 0;
686 }
687 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
688
689 drop:
690 rcu_read_unlock();
691 drop_nolock:
692 kfree_skb(skb);
693 return 0;
694 }
695
696 static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
697 {
698 struct ip_tunnel *tunnel = netdev_priv(dev);
699 struct pcpu_tstats *tstats;
700 struct iphdr *old_iph = ip_hdr(skb);
701 struct iphdr *tiph;
702 u8 tos;
703 __be16 df;
704 struct rtable *rt; /* Route to the other host */
705 struct net_device *tdev; /* Device to other host */
706 struct iphdr *iph; /* Our new IP header */
707 unsigned int max_headroom; /* The extra header space needed */
708 int gre_hlen;
709 __be32 dst;
710 int mtu;
711
712 if (dev->type == ARPHRD_ETHER)
713 IPCB(skb)->flags = 0;
714
715 if (dev->header_ops && dev->type == ARPHRD_IPGRE) {
716 gre_hlen = 0;
717 tiph = (struct iphdr *)skb->data;
718 } else {
719 gre_hlen = tunnel->hlen;
720 tiph = &tunnel->parms.iph;
721 }
722
723 if ((dst = tiph->daddr) == 0) {
724 /* NBMA tunnel */
725
726 if (skb_dst(skb) == NULL) {
727 dev->stats.tx_fifo_errors++;
728 goto tx_error;
729 }
730
731 if (skb->protocol == htons(ETH_P_IP)) {
732 rt = skb_rtable(skb);
733 if ((dst = rt->rt_gateway) == 0)
734 goto tx_error_icmp;
735 }
736 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
737 else if (skb->protocol == htons(ETH_P_IPV6)) {
738 struct in6_addr *addr6;
739 int addr_type;
740 struct neighbour *neigh = skb_dst(skb)->neighbour;
741
742 if (neigh == NULL)
743 goto tx_error;
744
745 addr6 = (struct in6_addr *)&neigh->primary_key;
746 addr_type = ipv6_addr_type(addr6);
747
748 if (addr_type == IPV6_ADDR_ANY) {
749 addr6 = &ipv6_hdr(skb)->daddr;
750 addr_type = ipv6_addr_type(addr6);
751 }
752
753 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
754 goto tx_error_icmp;
755
756 dst = addr6->s6_addr32[3];
757 }
758 #endif
759 else
760 goto tx_error;
761 }
762
763 tos = tiph->tos;
764 if (tos == 1) {
765 tos = 0;
766 if (skb->protocol == htons(ETH_P_IP))
767 tos = old_iph->tos;
768 else if (skb->protocol == htons(ETH_P_IPV6))
769 tos = ipv6_get_dsfield((struct ipv6hdr *)old_iph);
770 }
771
772 rt = ip_route_output_gre(dev_net(dev), dst, tiph->saddr,
773 tunnel->parms.o_key, RT_TOS(tos),
774 tunnel->parms.link);
775 if (IS_ERR(rt)) {
776 dev->stats.tx_carrier_errors++;
777 goto tx_error;
778 }
779 tdev = rt->dst.dev;
780
781 if (tdev == dev) {
782 ip_rt_put(rt);
783 dev->stats.collisions++;
784 goto tx_error;
785 }
786
787 df = tiph->frag_off;
788 if (df)
789 mtu = dst_mtu(&rt->dst) - dev->hard_header_len - tunnel->hlen;
790 else
791 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
792
793 if (skb_dst(skb))
794 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
795
796 if (skb->protocol == htons(ETH_P_IP)) {
797 df |= (old_iph->frag_off&htons(IP_DF));
798
799 if ((old_iph->frag_off&htons(IP_DF)) &&
800 mtu < ntohs(old_iph->tot_len)) {
801 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
802 ip_rt_put(rt);
803 goto tx_error;
804 }
805 }
806 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
807 else if (skb->protocol == htons(ETH_P_IPV6)) {
808 struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
809
810 if (rt6 && mtu < dst_mtu(skb_dst(skb)) && mtu >= IPV6_MIN_MTU) {
811 if ((tunnel->parms.iph.daddr &&
812 !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
813 rt6->rt6i_dst.plen == 128) {
814 rt6->rt6i_flags |= RTF_MODIFIED;
815 dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
816 }
817 }
818
819 if (mtu >= IPV6_MIN_MTU && mtu < skb->len - tunnel->hlen + gre_hlen) {
820 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
821 ip_rt_put(rt);
822 goto tx_error;
823 }
824 }
825 #endif
826
827 if (tunnel->err_count > 0) {
828 if (time_before(jiffies,
829 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
830 tunnel->err_count--;
831
832 dst_link_failure(skb);
833 } else
834 tunnel->err_count = 0;
835 }
836
837 max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + rt->dst.header_len;
838
839 if (skb_headroom(skb) < max_headroom || skb_shared(skb)||
840 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
841 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
842 if (max_headroom > dev->needed_headroom)
843 dev->needed_headroom = max_headroom;
844 if (!new_skb) {
845 ip_rt_put(rt);
846 dev->stats.tx_dropped++;
847 dev_kfree_skb(skb);
848 return NETDEV_TX_OK;
849 }
850 if (skb->sk)
851 skb_set_owner_w(new_skb, skb->sk);
852 dev_kfree_skb(skb);
853 skb = new_skb;
854 old_iph = ip_hdr(skb);
855 }
856
857 skb_reset_transport_header(skb);
858 skb_push(skb, gre_hlen);
859 skb_reset_network_header(skb);
860 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
861 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
862 IPSKB_REROUTED);
863 skb_dst_drop(skb);
864 skb_dst_set(skb, &rt->dst);
865
866 /*
867 * Push down and install the IPIP header.
868 */
869
870 iph = ip_hdr(skb);
871 iph->version = 4;
872 iph->ihl = sizeof(struct iphdr) >> 2;
873 iph->frag_off = df;
874 iph->protocol = IPPROTO_GRE;
875 iph->tos = ipgre_ecn_encapsulate(tos, old_iph, skb);
876 iph->daddr = rt->rt_dst;
877 iph->saddr = rt->rt_src;
878
879 if ((iph->ttl = tiph->ttl) == 0) {
880 if (skb->protocol == htons(ETH_P_IP))
881 iph->ttl = old_iph->ttl;
882 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
883 else if (skb->protocol == htons(ETH_P_IPV6))
884 iph->ttl = ((struct ipv6hdr *)old_iph)->hop_limit;
885 #endif
886 else
887 iph->ttl = ip4_dst_hoplimit(&rt->dst);
888 }
889
890 ((__be16 *)(iph + 1))[0] = tunnel->parms.o_flags;
891 ((__be16 *)(iph + 1))[1] = (dev->type == ARPHRD_ETHER) ?
892 htons(ETH_P_TEB) : skb->protocol;
893
894 if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) {
895 __be32 *ptr = (__be32*)(((u8*)iph) + tunnel->hlen - 4);
896
897 if (tunnel->parms.o_flags&GRE_SEQ) {
898 ++tunnel->o_seqno;
899 *ptr = htonl(tunnel->o_seqno);
900 ptr--;
901 }
902 if (tunnel->parms.o_flags&GRE_KEY) {
903 *ptr = tunnel->parms.o_key;
904 ptr--;
905 }
906 if (tunnel->parms.o_flags&GRE_CSUM) {
907 *ptr = 0;
908 *(__sum16*)ptr = ip_compute_csum((void*)(iph+1), skb->len - sizeof(struct iphdr));
909 }
910 }
911
912 nf_reset(skb);
913 tstats = this_cpu_ptr(dev->tstats);
914 __IPTUNNEL_XMIT(tstats, &dev->stats);
915 return NETDEV_TX_OK;
916
917 tx_error_icmp:
918 dst_link_failure(skb);
919
920 tx_error:
921 dev->stats.tx_errors++;
922 dev_kfree_skb(skb);
923 return NETDEV_TX_OK;
924 }
925
926 static int ipgre_tunnel_bind_dev(struct net_device *dev)
927 {
928 struct net_device *tdev = NULL;
929 struct ip_tunnel *tunnel;
930 struct iphdr *iph;
931 int hlen = LL_MAX_HEADER;
932 int mtu = ETH_DATA_LEN;
933 int addend = sizeof(struct iphdr) + 4;
934
935 tunnel = netdev_priv(dev);
936 iph = &tunnel->parms.iph;
937
938 /* Guess output device to choose reasonable mtu and needed_headroom */
939
940 if (iph->daddr) {
941 struct rtable *rt = ip_route_output_gre(dev_net(dev),
942 iph->daddr, iph->saddr,
943 tunnel->parms.o_key,
944 RT_TOS(iph->tos),
945 tunnel->parms.link);
946
947 if (!IS_ERR(rt)) {
948 tdev = rt->dst.dev;
949 ip_rt_put(rt);
950 }
951
952 if (dev->type != ARPHRD_ETHER)
953 dev->flags |= IFF_POINTOPOINT;
954 }
955
956 if (!tdev && tunnel->parms.link)
957 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
958
959 if (tdev) {
960 hlen = tdev->hard_header_len + tdev->needed_headroom;
961 mtu = tdev->mtu;
962 }
963 dev->iflink = tunnel->parms.link;
964
965 /* Precalculate GRE options length */
966 if (tunnel->parms.o_flags&(GRE_CSUM|GRE_KEY|GRE_SEQ)) {
967 if (tunnel->parms.o_flags&GRE_CSUM)
968 addend += 4;
969 if (tunnel->parms.o_flags&GRE_KEY)
970 addend += 4;
971 if (tunnel->parms.o_flags&GRE_SEQ)
972 addend += 4;
973 }
974 dev->needed_headroom = addend + hlen;
975 mtu -= dev->hard_header_len + addend;
976
977 if (mtu < 68)
978 mtu = 68;
979
980 tunnel->hlen = addend;
981
982 return mtu;
983 }
984
985 static int
986 ipgre_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
987 {
988 int err = 0;
989 struct ip_tunnel_parm p;
990 struct ip_tunnel *t;
991 struct net *net = dev_net(dev);
992 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
993
994 switch (cmd) {
995 case SIOCGETTUNNEL:
996 t = NULL;
997 if (dev == ign->fb_tunnel_dev) {
998 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
999 err = -EFAULT;
1000 break;
1001 }
1002 t = ipgre_tunnel_locate(net, &p, 0);
1003 }
1004 if (t == NULL)
1005 t = netdev_priv(dev);
1006 memcpy(&p, &t->parms, sizeof(p));
1007 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1008 err = -EFAULT;
1009 break;
1010
1011 case SIOCADDTUNNEL:
1012 case SIOCCHGTUNNEL:
1013 err = -EPERM;
1014 if (!capable(CAP_NET_ADMIN))
1015 goto done;
1016
1017 err = -EFAULT;
1018 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1019 goto done;
1020
1021 err = -EINVAL;
1022 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE ||
1023 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)) ||
1024 ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING)))
1025 goto done;
1026 if (p.iph.ttl)
1027 p.iph.frag_off |= htons(IP_DF);
1028
1029 if (!(p.i_flags&GRE_KEY))
1030 p.i_key = 0;
1031 if (!(p.o_flags&GRE_KEY))
1032 p.o_key = 0;
1033
1034 t = ipgre_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
1035
1036 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1037 if (t != NULL) {
1038 if (t->dev != dev) {
1039 err = -EEXIST;
1040 break;
1041 }
1042 } else {
1043 unsigned int nflags = 0;
1044
1045 t = netdev_priv(dev);
1046
1047 if (ipv4_is_multicast(p.iph.daddr))
1048 nflags = IFF_BROADCAST;
1049 else if (p.iph.daddr)
1050 nflags = IFF_POINTOPOINT;
1051
1052 if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) {
1053 err = -EINVAL;
1054 break;
1055 }
1056 ipgre_tunnel_unlink(ign, t);
1057 synchronize_net();
1058 t->parms.iph.saddr = p.iph.saddr;
1059 t->parms.iph.daddr = p.iph.daddr;
1060 t->parms.i_key = p.i_key;
1061 t->parms.o_key = p.o_key;
1062 memcpy(dev->dev_addr, &p.iph.saddr, 4);
1063 memcpy(dev->broadcast, &p.iph.daddr, 4);
1064 ipgre_tunnel_link(ign, t);
1065 netdev_state_change(dev);
1066 }
1067 }
1068
1069 if (t) {
1070 err = 0;
1071 if (cmd == SIOCCHGTUNNEL) {
1072 t->parms.iph.ttl = p.iph.ttl;
1073 t->parms.iph.tos = p.iph.tos;
1074 t->parms.iph.frag_off = p.iph.frag_off;
1075 if (t->parms.link != p.link) {
1076 t->parms.link = p.link;
1077 dev->mtu = ipgre_tunnel_bind_dev(dev);
1078 netdev_state_change(dev);
1079 }
1080 }
1081 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
1082 err = -EFAULT;
1083 } else
1084 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1085 break;
1086
1087 case SIOCDELTUNNEL:
1088 err = -EPERM;
1089 if (!capable(CAP_NET_ADMIN))
1090 goto done;
1091
1092 if (dev == ign->fb_tunnel_dev) {
1093 err = -EFAULT;
1094 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1095 goto done;
1096 err = -ENOENT;
1097 if ((t = ipgre_tunnel_locate(net, &p, 0)) == NULL)
1098 goto done;
1099 err = -EPERM;
1100 if (t == netdev_priv(ign->fb_tunnel_dev))
1101 goto done;
1102 dev = t->dev;
1103 }
1104 unregister_netdevice(dev);
1105 err = 0;
1106 break;
1107
1108 default:
1109 err = -EINVAL;
1110 }
1111
1112 done:
1113 return err;
1114 }
1115
1116 static int ipgre_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1117 {
1118 struct ip_tunnel *tunnel = netdev_priv(dev);
1119 if (new_mtu < 68 ||
1120 new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen)
1121 return -EINVAL;
1122 dev->mtu = new_mtu;
1123 return 0;
1124 }
1125
1126 /* Nice toy. Unfortunately, useless in real life :-)
1127 It allows to construct virtual multiprotocol broadcast "LAN"
1128 over the Internet, provided multicast routing is tuned.
1129
1130
1131 I have no idea was this bicycle invented before me,
1132 so that I had to set ARPHRD_IPGRE to a random value.
1133 I have an impression, that Cisco could make something similar,
1134 but this feature is apparently missing in IOS<=11.2(8).
1135
1136 I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks
1137 with broadcast 224.66.66.66. If you have access to mbone, play with me :-)
1138
1139 ping -t 255 224.66.66.66
1140
1141 If nobody answers, mbone does not work.
1142
1143 ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255
1144 ip addr add 10.66.66.<somewhat>/24 dev Universe
1145 ifconfig Universe up
1146 ifconfig Universe add fe80::<Your_real_addr>/10
1147 ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96
1148 ftp 10.66.66.66
1149 ...
1150 ftp fec0:6666:6666::193.233.7.65
1151 ...
1152
1153 */
1154
1155 static int ipgre_header(struct sk_buff *skb, struct net_device *dev,
1156 unsigned short type,
1157 const void *daddr, const void *saddr, unsigned int len)
1158 {
1159 struct ip_tunnel *t = netdev_priv(dev);
1160 struct iphdr *iph = (struct iphdr *)skb_push(skb, t->hlen);
1161 __be16 *p = (__be16*)(iph+1);
1162
1163 memcpy(iph, &t->parms.iph, sizeof(struct iphdr));
1164 p[0] = t->parms.o_flags;
1165 p[1] = htons(type);
1166
1167 /*
1168 * Set the source hardware address.
1169 */
1170
1171 if (saddr)
1172 memcpy(&iph->saddr, saddr, 4);
1173 if (daddr)
1174 memcpy(&iph->daddr, daddr, 4);
1175 if (iph->daddr)
1176 return t->hlen;
1177
1178 return -t->hlen;
1179 }
1180
1181 static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr)
1182 {
1183 struct iphdr *iph = (struct iphdr *) skb_mac_header(skb);
1184 memcpy(haddr, &iph->saddr, 4);
1185 return 4;
1186 }
1187
1188 static const struct header_ops ipgre_header_ops = {
1189 .create = ipgre_header,
1190 .parse = ipgre_header_parse,
1191 };
1192
1193 #ifdef CONFIG_NET_IPGRE_BROADCAST
1194 static int ipgre_open(struct net_device *dev)
1195 {
1196 struct ip_tunnel *t = netdev_priv(dev);
1197
1198 if (ipv4_is_multicast(t->parms.iph.daddr)) {
1199 struct rtable *rt = ip_route_output_gre(dev_net(dev),
1200 t->parms.iph.daddr,
1201 t->parms.iph.saddr,
1202 t->parms.o_key,
1203 RT_TOS(t->parms.iph.tos),
1204 t->parms.link);
1205
1206 if (IS_ERR(rt))
1207 return -EADDRNOTAVAIL;
1208 dev = rt->dst.dev;
1209 ip_rt_put(rt);
1210 if (__in_dev_get_rtnl(dev) == NULL)
1211 return -EADDRNOTAVAIL;
1212 t->mlink = dev->ifindex;
1213 ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
1214 }
1215 return 0;
1216 }
1217
1218 static int ipgre_close(struct net_device *dev)
1219 {
1220 struct ip_tunnel *t = netdev_priv(dev);
1221
1222 if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
1223 struct in_device *in_dev;
1224 in_dev = inetdev_by_index(dev_net(dev), t->mlink);
1225 if (in_dev)
1226 ip_mc_dec_group(in_dev, t->parms.iph.daddr);
1227 }
1228 return 0;
1229 }
1230
1231 #endif
1232
1233 static const struct net_device_ops ipgre_netdev_ops = {
1234 .ndo_init = ipgre_tunnel_init,
1235 .ndo_uninit = ipgre_tunnel_uninit,
1236 #ifdef CONFIG_NET_IPGRE_BROADCAST
1237 .ndo_open = ipgre_open,
1238 .ndo_stop = ipgre_close,
1239 #endif
1240 .ndo_start_xmit = ipgre_tunnel_xmit,
1241 .ndo_do_ioctl = ipgre_tunnel_ioctl,
1242 .ndo_change_mtu = ipgre_tunnel_change_mtu,
1243 .ndo_get_stats = ipgre_get_stats,
1244 };
1245
1246 static void ipgre_dev_free(struct net_device *dev)
1247 {
1248 free_percpu(dev->tstats);
1249 free_netdev(dev);
1250 }
1251
1252 static void ipgre_tunnel_setup(struct net_device *dev)
1253 {
1254 dev->netdev_ops = &ipgre_netdev_ops;
1255 dev->destructor = ipgre_dev_free;
1256
1257 dev->type = ARPHRD_IPGRE;
1258 dev->needed_headroom = LL_MAX_HEADER + sizeof(struct iphdr) + 4;
1259 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 4;
1260 dev->flags = IFF_NOARP;
1261 dev->iflink = 0;
1262 dev->addr_len = 4;
1263 dev->features |= NETIF_F_NETNS_LOCAL;
1264 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1265 }
1266
1267 static int ipgre_tunnel_init(struct net_device *dev)
1268 {
1269 struct ip_tunnel *tunnel;
1270 struct iphdr *iph;
1271
1272 tunnel = netdev_priv(dev);
1273 iph = &tunnel->parms.iph;
1274
1275 tunnel->dev = dev;
1276 strcpy(tunnel->parms.name, dev->name);
1277
1278 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
1279 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
1280
1281 if (iph->daddr) {
1282 #ifdef CONFIG_NET_IPGRE_BROADCAST
1283 if (ipv4_is_multicast(iph->daddr)) {
1284 if (!iph->saddr)
1285 return -EINVAL;
1286 dev->flags = IFF_BROADCAST;
1287 dev->header_ops = &ipgre_header_ops;
1288 }
1289 #endif
1290 } else
1291 dev->header_ops = &ipgre_header_ops;
1292
1293 dev->tstats = alloc_percpu(struct pcpu_tstats);
1294 if (!dev->tstats)
1295 return -ENOMEM;
1296
1297 return 0;
1298 }
1299
1300 static void ipgre_fb_tunnel_init(struct net_device *dev)
1301 {
1302 struct ip_tunnel *tunnel = netdev_priv(dev);
1303 struct iphdr *iph = &tunnel->parms.iph;
1304
1305 tunnel->dev = dev;
1306 strcpy(tunnel->parms.name, dev->name);
1307
1308 iph->version = 4;
1309 iph->protocol = IPPROTO_GRE;
1310 iph->ihl = 5;
1311 tunnel->hlen = sizeof(struct iphdr) + 4;
1312
1313 dev_hold(dev);
1314 }
1315
1316
1317 static const struct gre_protocol ipgre_protocol = {
1318 .handler = ipgre_rcv,
1319 .err_handler = ipgre_err,
1320 };
1321
1322 static void ipgre_destroy_tunnels(struct ipgre_net *ign, struct list_head *head)
1323 {
1324 int prio;
1325
1326 for (prio = 0; prio < 4; prio++) {
1327 int h;
1328 for (h = 0; h < HASH_SIZE; h++) {
1329 struct ip_tunnel *t;
1330
1331 t = rtnl_dereference(ign->tunnels[prio][h]);
1332
1333 while (t != NULL) {
1334 unregister_netdevice_queue(t->dev, head);
1335 t = rtnl_dereference(t->next);
1336 }
1337 }
1338 }
1339 }
1340
1341 static int __net_init ipgre_init_net(struct net *net)
1342 {
1343 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
1344 int err;
1345
1346 ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "gre0",
1347 ipgre_tunnel_setup);
1348 if (!ign->fb_tunnel_dev) {
1349 err = -ENOMEM;
1350 goto err_alloc_dev;
1351 }
1352 dev_net_set(ign->fb_tunnel_dev, net);
1353
1354 ipgre_fb_tunnel_init(ign->fb_tunnel_dev);
1355 ign->fb_tunnel_dev->rtnl_link_ops = &ipgre_link_ops;
1356
1357 if ((err = register_netdev(ign->fb_tunnel_dev)))
1358 goto err_reg_dev;
1359
1360 rcu_assign_pointer(ign->tunnels_wc[0],
1361 netdev_priv(ign->fb_tunnel_dev));
1362 return 0;
1363
1364 err_reg_dev:
1365 ipgre_dev_free(ign->fb_tunnel_dev);
1366 err_alloc_dev:
1367 return err;
1368 }
1369
1370 static void __net_exit ipgre_exit_net(struct net *net)
1371 {
1372 struct ipgre_net *ign;
1373 LIST_HEAD(list);
1374
1375 ign = net_generic(net, ipgre_net_id);
1376 rtnl_lock();
1377 ipgre_destroy_tunnels(ign, &list);
1378 unregister_netdevice_many(&list);
1379 rtnl_unlock();
1380 }
1381
1382 static struct pernet_operations ipgre_net_ops = {
1383 .init = ipgre_init_net,
1384 .exit = ipgre_exit_net,
1385 .id = &ipgre_net_id,
1386 .size = sizeof(struct ipgre_net),
1387 };
1388
1389 static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
1390 {
1391 __be16 flags;
1392
1393 if (!data)
1394 return 0;
1395
1396 flags = 0;
1397 if (data[IFLA_GRE_IFLAGS])
1398 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1399 if (data[IFLA_GRE_OFLAGS])
1400 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1401 if (flags & (GRE_VERSION|GRE_ROUTING))
1402 return -EINVAL;
1403
1404 return 0;
1405 }
1406
1407 static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[])
1408 {
1409 __be32 daddr;
1410
1411 if (tb[IFLA_ADDRESS]) {
1412 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1413 return -EINVAL;
1414 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1415 return -EADDRNOTAVAIL;
1416 }
1417
1418 if (!data)
1419 goto out;
1420
1421 if (data[IFLA_GRE_REMOTE]) {
1422 memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4);
1423 if (!daddr)
1424 return -EINVAL;
1425 }
1426
1427 out:
1428 return ipgre_tunnel_validate(tb, data);
1429 }
1430
1431 static void ipgre_netlink_parms(struct nlattr *data[],
1432 struct ip_tunnel_parm *parms)
1433 {
1434 memset(parms, 0, sizeof(*parms));
1435
1436 parms->iph.protocol = IPPROTO_GRE;
1437
1438 if (!data)
1439 return;
1440
1441 if (data[IFLA_GRE_LINK])
1442 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1443
1444 if (data[IFLA_GRE_IFLAGS])
1445 parms->i_flags = nla_get_be16(data[IFLA_GRE_IFLAGS]);
1446
1447 if (data[IFLA_GRE_OFLAGS])
1448 parms->o_flags = nla_get_be16(data[IFLA_GRE_OFLAGS]);
1449
1450 if (data[IFLA_GRE_IKEY])
1451 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1452
1453 if (data[IFLA_GRE_OKEY])
1454 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1455
1456 if (data[IFLA_GRE_LOCAL])
1457 parms->iph.saddr = nla_get_be32(data[IFLA_GRE_LOCAL]);
1458
1459 if (data[IFLA_GRE_REMOTE])
1460 parms->iph.daddr = nla_get_be32(data[IFLA_GRE_REMOTE]);
1461
1462 if (data[IFLA_GRE_TTL])
1463 parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]);
1464
1465 if (data[IFLA_GRE_TOS])
1466 parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
1467
1468 if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC]))
1469 parms->iph.frag_off = htons(IP_DF);
1470 }
1471
1472 static int ipgre_tap_init(struct net_device *dev)
1473 {
1474 struct ip_tunnel *tunnel;
1475
1476 tunnel = netdev_priv(dev);
1477
1478 tunnel->dev = dev;
1479 strcpy(tunnel->parms.name, dev->name);
1480
1481 ipgre_tunnel_bind_dev(dev);
1482
1483 dev->tstats = alloc_percpu(struct pcpu_tstats);
1484 if (!dev->tstats)
1485 return -ENOMEM;
1486
1487 return 0;
1488 }
1489
1490 static const struct net_device_ops ipgre_tap_netdev_ops = {
1491 .ndo_init = ipgre_tap_init,
1492 .ndo_uninit = ipgre_tunnel_uninit,
1493 .ndo_start_xmit = ipgre_tunnel_xmit,
1494 .ndo_set_mac_address = eth_mac_addr,
1495 .ndo_validate_addr = eth_validate_addr,
1496 .ndo_change_mtu = ipgre_tunnel_change_mtu,
1497 .ndo_get_stats = ipgre_get_stats,
1498 };
1499
1500 static void ipgre_tap_setup(struct net_device *dev)
1501 {
1502
1503 ether_setup(dev);
1504
1505 dev->netdev_ops = &ipgre_tap_netdev_ops;
1506 dev->destructor = ipgre_dev_free;
1507
1508 dev->iflink = 0;
1509 dev->features |= NETIF_F_NETNS_LOCAL;
1510 }
1511
1512 static int ipgre_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[],
1513 struct nlattr *data[])
1514 {
1515 struct ip_tunnel *nt;
1516 struct net *net = dev_net(dev);
1517 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
1518 int mtu;
1519 int err;
1520
1521 nt = netdev_priv(dev);
1522 ipgre_netlink_parms(data, &nt->parms);
1523
1524 if (ipgre_tunnel_find(net, &nt->parms, dev->type))
1525 return -EEXIST;
1526
1527 if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1528 random_ether_addr(dev->dev_addr);
1529
1530 mtu = ipgre_tunnel_bind_dev(dev);
1531 if (!tb[IFLA_MTU])
1532 dev->mtu = mtu;
1533
1534 /* Can use a lockless transmit, unless we generate output sequences */
1535 if (!(nt->parms.o_flags & GRE_SEQ))
1536 dev->features |= NETIF_F_LLTX;
1537
1538 err = register_netdevice(dev);
1539 if (err)
1540 goto out;
1541
1542 dev_hold(dev);
1543 ipgre_tunnel_link(ign, nt);
1544
1545 out:
1546 return err;
1547 }
1548
1549 static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
1550 struct nlattr *data[])
1551 {
1552 struct ip_tunnel *t, *nt;
1553 struct net *net = dev_net(dev);
1554 struct ipgre_net *ign = net_generic(net, ipgre_net_id);
1555 struct ip_tunnel_parm p;
1556 int mtu;
1557
1558 if (dev == ign->fb_tunnel_dev)
1559 return -EINVAL;
1560
1561 nt = netdev_priv(dev);
1562 ipgre_netlink_parms(data, &p);
1563
1564 t = ipgre_tunnel_locate(net, &p, 0);
1565
1566 if (t) {
1567 if (t->dev != dev)
1568 return -EEXIST;
1569 } else {
1570 t = nt;
1571
1572 if (dev->type != ARPHRD_ETHER) {
1573 unsigned int nflags = 0;
1574
1575 if (ipv4_is_multicast(p.iph.daddr))
1576 nflags = IFF_BROADCAST;
1577 else if (p.iph.daddr)
1578 nflags = IFF_POINTOPOINT;
1579
1580 if ((dev->flags ^ nflags) &
1581 (IFF_POINTOPOINT | IFF_BROADCAST))
1582 return -EINVAL;
1583 }
1584
1585 ipgre_tunnel_unlink(ign, t);
1586 t->parms.iph.saddr = p.iph.saddr;
1587 t->parms.iph.daddr = p.iph.daddr;
1588 t->parms.i_key = p.i_key;
1589 if (dev->type != ARPHRD_ETHER) {
1590 memcpy(dev->dev_addr, &p.iph.saddr, 4);
1591 memcpy(dev->broadcast, &p.iph.daddr, 4);
1592 }
1593 ipgre_tunnel_link(ign, t);
1594 netdev_state_change(dev);
1595 }
1596
1597 t->parms.o_key = p.o_key;
1598 t->parms.iph.ttl = p.iph.ttl;
1599 t->parms.iph.tos = p.iph.tos;
1600 t->parms.iph.frag_off = p.iph.frag_off;
1601
1602 if (t->parms.link != p.link) {
1603 t->parms.link = p.link;
1604 mtu = ipgre_tunnel_bind_dev(dev);
1605 if (!tb[IFLA_MTU])
1606 dev->mtu = mtu;
1607 netdev_state_change(dev);
1608 }
1609
1610 return 0;
1611 }
1612
1613 static size_t ipgre_get_size(const struct net_device *dev)
1614 {
1615 return
1616 /* IFLA_GRE_LINK */
1617 nla_total_size(4) +
1618 /* IFLA_GRE_IFLAGS */
1619 nla_total_size(2) +
1620 /* IFLA_GRE_OFLAGS */
1621 nla_total_size(2) +
1622 /* IFLA_GRE_IKEY */
1623 nla_total_size(4) +
1624 /* IFLA_GRE_OKEY */
1625 nla_total_size(4) +
1626 /* IFLA_GRE_LOCAL */
1627 nla_total_size(4) +
1628 /* IFLA_GRE_REMOTE */
1629 nla_total_size(4) +
1630 /* IFLA_GRE_TTL */
1631 nla_total_size(1) +
1632 /* IFLA_GRE_TOS */
1633 nla_total_size(1) +
1634 /* IFLA_GRE_PMTUDISC */
1635 nla_total_size(1) +
1636 0;
1637 }
1638
1639 static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
1640 {
1641 struct ip_tunnel *t = netdev_priv(dev);
1642 struct ip_tunnel_parm *p = &t->parms;
1643
1644 NLA_PUT_U32(skb, IFLA_GRE_LINK, p->link);
1645 NLA_PUT_BE16(skb, IFLA_GRE_IFLAGS, p->i_flags);
1646 NLA_PUT_BE16(skb, IFLA_GRE_OFLAGS, p->o_flags);
1647 NLA_PUT_BE32(skb, IFLA_GRE_IKEY, p->i_key);
1648 NLA_PUT_BE32(skb, IFLA_GRE_OKEY, p->o_key);
1649 NLA_PUT_BE32(skb, IFLA_GRE_LOCAL, p->iph.saddr);
1650 NLA_PUT_BE32(skb, IFLA_GRE_REMOTE, p->iph.daddr);
1651 NLA_PUT_U8(skb, IFLA_GRE_TTL, p->iph.ttl);
1652 NLA_PUT_U8(skb, IFLA_GRE_TOS, p->iph.tos);
1653 NLA_PUT_U8(skb, IFLA_GRE_PMTUDISC, !!(p->iph.frag_off & htons(IP_DF)));
1654
1655 return 0;
1656
1657 nla_put_failure:
1658 return -EMSGSIZE;
1659 }
1660
1661 static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
1662 [IFLA_GRE_LINK] = { .type = NLA_U32 },
1663 [IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
1664 [IFLA_GRE_OFLAGS] = { .type = NLA_U16 },
1665 [IFLA_GRE_IKEY] = { .type = NLA_U32 },
1666 [IFLA_GRE_OKEY] = { .type = NLA_U32 },
1667 [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
1668 [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
1669 [IFLA_GRE_TTL] = { .type = NLA_U8 },
1670 [IFLA_GRE_TOS] = { .type = NLA_U8 },
1671 [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 },
1672 };
1673
1674 static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
1675 .kind = "gre",
1676 .maxtype = IFLA_GRE_MAX,
1677 .policy = ipgre_policy,
1678 .priv_size = sizeof(struct ip_tunnel),
1679 .setup = ipgre_tunnel_setup,
1680 .validate = ipgre_tunnel_validate,
1681 .newlink = ipgre_newlink,
1682 .changelink = ipgre_changelink,
1683 .get_size = ipgre_get_size,
1684 .fill_info = ipgre_fill_info,
1685 };
1686
1687 static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
1688 .kind = "gretap",
1689 .maxtype = IFLA_GRE_MAX,
1690 .policy = ipgre_policy,
1691 .priv_size = sizeof(struct ip_tunnel),
1692 .setup = ipgre_tap_setup,
1693 .validate = ipgre_tap_validate,
1694 .newlink = ipgre_newlink,
1695 .changelink = ipgre_changelink,
1696 .get_size = ipgre_get_size,
1697 .fill_info = ipgre_fill_info,
1698 };
1699
1700 /*
1701 * And now the modules code and kernel interface.
1702 */
1703
1704 static int __init ipgre_init(void)
1705 {
1706 int err;
1707
1708 printk(KERN_INFO "GRE over IPv4 tunneling driver\n");
1709
1710 err = register_pernet_device(&ipgre_net_ops);
1711 if (err < 0)
1712 return err;
1713
1714 err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
1715 if (err < 0) {
1716 printk(KERN_INFO "ipgre init: can't add protocol\n");
1717 goto add_proto_failed;
1718 }
1719
1720 err = rtnl_link_register(&ipgre_link_ops);
1721 if (err < 0)
1722 goto rtnl_link_failed;
1723
1724 err = rtnl_link_register(&ipgre_tap_ops);
1725 if (err < 0)
1726 goto tap_ops_failed;
1727
1728 out:
1729 return err;
1730
1731 tap_ops_failed:
1732 rtnl_link_unregister(&ipgre_link_ops);
1733 rtnl_link_failed:
1734 gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
1735 add_proto_failed:
1736 unregister_pernet_device(&ipgre_net_ops);
1737 goto out;
1738 }
1739
1740 static void __exit ipgre_fini(void)
1741 {
1742 rtnl_link_unregister(&ipgre_tap_ops);
1743 rtnl_link_unregister(&ipgre_link_ops);
1744 if (gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO) < 0)
1745 printk(KERN_INFO "ipgre close: can't remove protocol\n");
1746 unregister_pernet_device(&ipgre_net_ops);
1747 }
1748
1749 module_init(ipgre_init);
1750 module_exit(ipgre_fini);
1751 MODULE_LICENSE("GPL");
1752 MODULE_ALIAS_RTNL_LINK("gre");
1753 MODULE_ALIAS_RTNL_LINK("gretap");
1754 MODULE_ALIAS_NETDEV("gre0");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree