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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc
[cris-mirror.git] / net / ipv6 / sit.c
blob43b33373adb2ec8e30420f0acea1367da404d820
1 /*
2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 *
14 * Changes:
15 * Roger Venning <r.venning@telstra.com>: 6to4 support
16 * Nate Thompson <nate@thebog.net>: 6to4 support
17 * Fred Templin <fred.l.templin@boeing.com>: isatap support
18 */
19
20 #include <linux/module.h>
21 #include <linux/capability.h>
22 #include <linux/errno.h>
23 #include <linux/types.h>
24 #include <linux/socket.h>
25 #include <linux/sockios.h>
26 #include <linux/net.h>
27 #include <linux/in6.h>
28 #include <linux/netdevice.h>
29 #include <linux/if_arp.h>
30 #include <linux/icmp.h>
31 #include <linux/slab.h>
32 #include <asm/uaccess.h>
33 #include <linux/init.h>
34 #include <linux/netfilter_ipv4.h>
35 #include <linux/if_ether.h>
36
37 #include <net/sock.h>
38 #include <net/snmp.h>
39
40 #include <net/ipv6.h>
41 #include <net/protocol.h>
42 #include <net/transp_v6.h>
43 #include <net/ip6_fib.h>
44 #include <net/ip6_route.h>
45 #include <net/ndisc.h>
46 #include <net/addrconf.h>
47 #include <net/ip.h>
48 #include <net/udp.h>
49 #include <net/icmp.h>
50 #include <net/ipip.h>
51 #include <net/inet_ecn.h>
52 #include <net/xfrm.h>
53 #include <net/dsfield.h>
54 #include <net/net_namespace.h>
55 #include <net/netns/generic.h>
56
57 /*
58 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
59
60 For comments look at net/ipv4/ip_gre.c --ANK
61 */
62
63 #define HASH_SIZE 16
64 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
65
66 static int ipip6_tunnel_init(struct net_device *dev);
67 static void ipip6_tunnel_setup(struct net_device *dev);
68 static void ipip6_dev_free(struct net_device *dev);
69
70 static int sit_net_id __read_mostly;
71 struct sit_net {
72 struct ip_tunnel __rcu *tunnels_r_l[HASH_SIZE];
73 struct ip_tunnel __rcu *tunnels_r[HASH_SIZE];
74 struct ip_tunnel __rcu *tunnels_l[HASH_SIZE];
75 struct ip_tunnel __rcu *tunnels_wc[1];
76 struct ip_tunnel __rcu **tunnels[4];
77
78 struct net_device *fb_tunnel_dev;
79 };
80
81 /*
82 * Locking : hash tables are protected by RCU and RTNL
83 */
84
85 #define for_each_ip_tunnel_rcu(start) \
86 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
87
88 /* often modified stats are per cpu, other are shared (netdev->stats) */
89 struct pcpu_tstats {
90 unsigned long rx_packets;
91 unsigned long rx_bytes;
92 unsigned long tx_packets;
93 unsigned long tx_bytes;
94 };
95
96 static struct net_device_stats *ipip6_get_stats(struct net_device *dev)
97 {
98 struct pcpu_tstats sum = { 0 };
99 int i;
100
101 for_each_possible_cpu(i) {
102 const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
103
104 sum.rx_packets += tstats->rx_packets;
105 sum.rx_bytes += tstats->rx_bytes;
106 sum.tx_packets += tstats->tx_packets;
107 sum.tx_bytes += tstats->tx_bytes;
108 }
109 dev->stats.rx_packets = sum.rx_packets;
110 dev->stats.rx_bytes = sum.rx_bytes;
111 dev->stats.tx_packets = sum.tx_packets;
112 dev->stats.tx_bytes = sum.tx_bytes;
113 return &dev->stats;
114 }
115 /*
116 * Must be invoked with rcu_read_lock
117 */
118 static struct ip_tunnel * ipip6_tunnel_lookup(struct net *net,
119 struct net_device *dev, __be32 remote, __be32 local)
120 {
121 unsigned int h0 = HASH(remote);
122 unsigned int h1 = HASH(local);
123 struct ip_tunnel *t;
124 struct sit_net *sitn = net_generic(net, sit_net_id);
125
126 for_each_ip_tunnel_rcu(sitn->tunnels_r_l[h0 ^ h1]) {
127 if (local == t->parms.iph.saddr &&
128 remote == t->parms.iph.daddr &&
129 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
130 (t->dev->flags & IFF_UP))
131 return t;
132 }
133 for_each_ip_tunnel_rcu(sitn->tunnels_r[h0]) {
134 if (remote == t->parms.iph.daddr &&
135 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
136 (t->dev->flags & IFF_UP))
137 return t;
138 }
139 for_each_ip_tunnel_rcu(sitn->tunnels_l[h1]) {
140 if (local == t->parms.iph.saddr &&
141 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
142 (t->dev->flags & IFF_UP))
143 return t;
144 }
145 t = rcu_dereference(sitn->tunnels_wc[0]);
146 if ((t != NULL) && (t->dev->flags & IFF_UP))
147 return t;
148 return NULL;
149 }
150
151 static struct ip_tunnel __rcu **__ipip6_bucket(struct sit_net *sitn,
152 struct ip_tunnel_parm *parms)
153 {
154 __be32 remote = parms->iph.daddr;
155 __be32 local = parms->iph.saddr;
156 unsigned int h = 0;
157 int prio = 0;
158
159 if (remote) {
160 prio |= 2;
161 h ^= HASH(remote);
162 }
163 if (local) {
164 prio |= 1;
165 h ^= HASH(local);
166 }
167 return &sitn->tunnels[prio][h];
168 }
169
170 static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn,
171 struct ip_tunnel *t)
172 {
173 return __ipip6_bucket(sitn, &t->parms);
174 }
175
176 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
177 {
178 struct ip_tunnel __rcu **tp;
179 struct ip_tunnel *iter;
180
181 for (tp = ipip6_bucket(sitn, t);
182 (iter = rtnl_dereference(*tp)) != NULL;
183 tp = &iter->next) {
184 if (t == iter) {
185 rcu_assign_pointer(*tp, t->next);
186 break;
187 }
188 }
189 }
190
191 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
192 {
193 struct ip_tunnel __rcu **tp = ipip6_bucket(sitn, t);
194
195 rcu_assign_pointer(t->next, rtnl_dereference(*tp));
196 rcu_assign_pointer(*tp, t);
197 }
198
199 static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
200 {
201 #ifdef CONFIG_IPV6_SIT_6RD
202 struct ip_tunnel *t = netdev_priv(dev);
203
204 if (t->dev == sitn->fb_tunnel_dev) {
205 ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0);
206 t->ip6rd.relay_prefix = 0;
207 t->ip6rd.prefixlen = 16;
208 t->ip6rd.relay_prefixlen = 0;
209 } else {
210 struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev);
211 memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd));
212 }
213 #endif
214 }
215
216 static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
217 struct ip_tunnel_parm *parms, int create)
218 {
219 __be32 remote = parms->iph.daddr;
220 __be32 local = parms->iph.saddr;
221 struct ip_tunnel *t, *nt;
222 struct ip_tunnel __rcu **tp;
223 struct net_device *dev;
224 char name[IFNAMSIZ];
225 struct sit_net *sitn = net_generic(net, sit_net_id);
226
227 for (tp = __ipip6_bucket(sitn, parms);
228 (t = rtnl_dereference(*tp)) != NULL;
229 tp = &t->next) {
230 if (local == t->parms.iph.saddr &&
231 remote == t->parms.iph.daddr &&
232 parms->link == t->parms.link) {
233 if (create)
234 return NULL;
235 else
236 return t;
237 }
238 }
239 if (!create)
240 goto failed;
241
242 if (parms->name[0])
243 strlcpy(name, parms->name, IFNAMSIZ);
244 else
245 strcpy(name, "sit%d");
246
247 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
248 if (dev == NULL)
249 return NULL;
250
251 dev_net_set(dev, net);
252
253 if (strchr(name, '%')) {
254 if (dev_alloc_name(dev, name) < 0)
255 goto failed_free;
256 }
257
258 nt = netdev_priv(dev);
259
260 nt->parms = *parms;
261 if (ipip6_tunnel_init(dev) < 0)
262 goto failed_free;
263 ipip6_tunnel_clone_6rd(dev, sitn);
264
265 if (parms->i_flags & SIT_ISATAP)
266 dev->priv_flags |= IFF_ISATAP;
267
268 if (register_netdevice(dev) < 0)
269 goto failed_free;
270
271 dev_hold(dev);
272
273 ipip6_tunnel_link(sitn, nt);
274 return nt;
275
276 failed_free:
277 ipip6_dev_free(dev);
278 failed:
279 return NULL;
280 }
281
282 #define for_each_prl_rcu(start) \
283 for (prl = rcu_dereference(start); \
284 prl; \
285 prl = rcu_dereference(prl->next))
286
287 static struct ip_tunnel_prl_entry *
288 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
289 {
290 struct ip_tunnel_prl_entry *prl;
291
292 for_each_prl_rcu(t->prl)
293 if (prl->addr == addr)
294 break;
295 return prl;
296
297 }
298
299 static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
300 struct ip_tunnel_prl __user *a)
301 {
302 struct ip_tunnel_prl kprl, *kp;
303 struct ip_tunnel_prl_entry *prl;
304 unsigned int cmax, c = 0, ca, len;
305 int ret = 0;
306
307 if (copy_from_user(&kprl, a, sizeof(kprl)))
308 return -EFAULT;
309 cmax = kprl.datalen / sizeof(kprl);
310 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
311 cmax = 1;
312
313 /* For simple GET or for root users,
314 * we try harder to allocate.
315 */
316 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
317 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
318 NULL;
319
320 rcu_read_lock();
321
322 ca = t->prl_count < cmax ? t->prl_count : cmax;
323
324 if (!kp) {
325 /* We don't try hard to allocate much memory for
326 * non-root users.
327 * For root users, retry allocating enough memory for
328 * the answer.
329 */
330 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
331 if (!kp) {
332 ret = -ENOMEM;
333 goto out;
334 }
335 }
336
337 c = 0;
338 for_each_prl_rcu(t->prl) {
339 if (c >= cmax)
340 break;
341 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
342 continue;
343 kp[c].addr = prl->addr;
344 kp[c].flags = prl->flags;
345 c++;
346 if (kprl.addr != htonl(INADDR_ANY))
347 break;
348 }
349 out:
350 rcu_read_unlock();
351
352 len = sizeof(*kp) * c;
353 ret = 0;
354 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
355 ret = -EFAULT;
356
357 kfree(kp);
358
359 return ret;
360 }
361
362 static int
363 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
364 {
365 struct ip_tunnel_prl_entry *p;
366 int err = 0;
367
368 if (a->addr == htonl(INADDR_ANY))
369 return -EINVAL;
370
371 ASSERT_RTNL();
372
373 for (p = rtnl_dereference(t->prl); p; p = rtnl_dereference(p->next)) {
374 if (p->addr == a->addr) {
375 if (chg) {
376 p->flags = a->flags;
377 goto out;
378 }
379 err = -EEXIST;
380 goto out;
381 }
382 }
383
384 if (chg) {
385 err = -ENXIO;
386 goto out;
387 }
388
389 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
390 if (!p) {
391 err = -ENOBUFS;
392 goto out;
393 }
394
395 p->next = t->prl;
396 p->addr = a->addr;
397 p->flags = a->flags;
398 t->prl_count++;
399 rcu_assign_pointer(t->prl, p);
400 out:
401 return err;
402 }
403
404 static void prl_entry_destroy_rcu(struct rcu_head *head)
405 {
406 kfree(container_of(head, struct ip_tunnel_prl_entry, rcu_head));
407 }
408
409 static void prl_list_destroy_rcu(struct rcu_head *head)
410 {
411 struct ip_tunnel_prl_entry *p, *n;
412
413 p = container_of(head, struct ip_tunnel_prl_entry, rcu_head);
414 do {
415 n = rcu_dereference_protected(p->next, 1);
416 kfree(p);
417 p = n;
418 } while (p);
419 }
420
421 static int
422 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
423 {
424 struct ip_tunnel_prl_entry *x;
425 struct ip_tunnel_prl_entry __rcu **p;
426 int err = 0;
427
428 ASSERT_RTNL();
429
430 if (a && a->addr != htonl(INADDR_ANY)) {
431 for (p = &t->prl;
432 (x = rtnl_dereference(*p)) != NULL;
433 p = &x->next) {
434 if (x->addr == a->addr) {
435 *p = x->next;
436 call_rcu(&x->rcu_head, prl_entry_destroy_rcu);
437 t->prl_count--;
438 goto out;
439 }
440 }
441 err = -ENXIO;
442 } else {
443 x = rtnl_dereference(t->prl);
444 if (x) {
445 t->prl_count = 0;
446 call_rcu(&x->rcu_head, prl_list_destroy_rcu);
447 t->prl = NULL;
448 }
449 }
450 out:
451 return err;
452 }
453
454 static int
455 isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
456 {
457 struct ip_tunnel_prl_entry *p;
458 int ok = 1;
459
460 rcu_read_lock();
461 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
462 if (p) {
463 if (p->flags & PRL_DEFAULT)
464 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
465 else
466 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
467 } else {
468 struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
469 if (ipv6_addr_is_isatap(addr6) &&
470 (addr6->s6_addr32[3] == iph->saddr) &&
471 ipv6_chk_prefix(addr6, t->dev))
472 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
473 else
474 ok = 0;
475 }
476 rcu_read_unlock();
477 return ok;
478 }
479
480 static void ipip6_tunnel_uninit(struct net_device *dev)
481 {
482 struct net *net = dev_net(dev);
483 struct sit_net *sitn = net_generic(net, sit_net_id);
484
485 if (dev == sitn->fb_tunnel_dev) {
486 rcu_assign_pointer(sitn->tunnels_wc[0], NULL);
487 } else {
488 ipip6_tunnel_unlink(sitn, netdev_priv(dev));
489 ipip6_tunnel_del_prl(netdev_priv(dev), NULL);
490 }
491 dev_put(dev);
492 }
493
494
495 static int ipip6_err(struct sk_buff *skb, u32 info)
496 {
497
498 /* All the routers (except for Linux) return only
499 8 bytes of packet payload. It means, that precise relaying of
500 ICMP in the real Internet is absolutely infeasible.
501 */
502 struct iphdr *iph = (struct iphdr*)skb->data;
503 const int type = icmp_hdr(skb)->type;
504 const int code = icmp_hdr(skb)->code;
505 struct ip_tunnel *t;
506 int err;
507
508 switch (type) {
509 default:
510 case ICMP_PARAMETERPROB:
511 return 0;
512
513 case ICMP_DEST_UNREACH:
514 switch (code) {
515 case ICMP_SR_FAILED:
516 case ICMP_PORT_UNREACH:
517 /* Impossible event. */
518 return 0;
519 case ICMP_FRAG_NEEDED:
520 /* Soft state for pmtu is maintained by IP core. */
521 return 0;
522 default:
523 /* All others are translated to HOST_UNREACH.
524 rfc2003 contains "deep thoughts" about NET_UNREACH,
525 I believe they are just ether pollution. --ANK
526 */
527 break;
528 }
529 break;
530 case ICMP_TIME_EXCEEDED:
531 if (code != ICMP_EXC_TTL)
532 return 0;
533 break;
534 }
535
536 err = -ENOENT;
537
538 rcu_read_lock();
539 t = ipip6_tunnel_lookup(dev_net(skb->dev),
540 skb->dev,
541 iph->daddr,
542 iph->saddr);
543 if (t == NULL || t->parms.iph.daddr == 0)
544 goto out;
545
546 err = 0;
547 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
548 goto out;
549
550 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
551 t->err_count++;
552 else
553 t->err_count = 1;
554 t->err_time = jiffies;
555 out:
556 rcu_read_unlock();
557 return err;
558 }
559
560 static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
561 {
562 if (INET_ECN_is_ce(iph->tos))
563 IP6_ECN_set_ce(ipv6_hdr(skb));
564 }
565
566 static int ipip6_rcv(struct sk_buff *skb)
567 {
568 struct iphdr *iph;
569 struct ip_tunnel *tunnel;
570
571 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
572 goto out;
573
574 iph = ip_hdr(skb);
575
576 rcu_read_lock();
577 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
578 iph->saddr, iph->daddr);
579 if (tunnel != NULL) {
580 struct pcpu_tstats *tstats;
581
582 secpath_reset(skb);
583 skb->mac_header = skb->network_header;
584 skb_reset_network_header(skb);
585 IPCB(skb)->flags = 0;
586 skb->protocol = htons(ETH_P_IPV6);
587 skb->pkt_type = PACKET_HOST;
588
589 if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
590 !isatap_chksrc(skb, iph, tunnel)) {
591 tunnel->dev->stats.rx_errors++;
592 rcu_read_unlock();
593 kfree_skb(skb);
594 return 0;
595 }
596
597 tstats = this_cpu_ptr(tunnel->dev->tstats);
598 tstats->rx_packets++;
599 tstats->rx_bytes += skb->len;
600
601 __skb_tunnel_rx(skb, tunnel->dev);
602
603 ipip6_ecn_decapsulate(iph, skb);
604
605 netif_rx(skb);
606
607 rcu_read_unlock();
608 return 0;
609 }
610
611 /* no tunnel matched, let upstream know, ipsec may handle it */
612 rcu_read_unlock();
613 return 1;
614 out:
615 kfree_skb(skb);
616 return 0;
617 }
618
619 /*
620 * Returns the embedded IPv4 address if the IPv6 address
621 * comes from 6rd / 6to4 (RFC 3056) addr space.
622 */
623 static inline
624 __be32 try_6rd(struct in6_addr *v6dst, struct ip_tunnel *tunnel)
625 {
626 __be32 dst = 0;
627
628 #ifdef CONFIG_IPV6_SIT_6RD
629 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
630 tunnel->ip6rd.prefixlen)) {
631 unsigned int pbw0, pbi0;
632 int pbi1;
633 u32 d;
634
635 pbw0 = tunnel->ip6rd.prefixlen >> 5;
636 pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
637
638 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
639 tunnel->ip6rd.relay_prefixlen;
640
641 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
642 if (pbi1 > 0)
643 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
644 (32 - pbi1);
645
646 dst = tunnel->ip6rd.relay_prefix | htonl(d);
647 }
648 #else
649 if (v6dst->s6_addr16[0] == htons(0x2002)) {
650 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
651 memcpy(&dst, &v6dst->s6_addr16[1], 4);
652 }
653 #endif
654 return dst;
655 }
656
657 /*
658 * This function assumes it is being called from dev_queue_xmit()
659 * and that skb is filled properly by that function.
660 */
661
662 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
663 struct net_device *dev)
664 {
665 struct ip_tunnel *tunnel = netdev_priv(dev);
666 struct pcpu_tstats *tstats;
667 struct iphdr *tiph = &tunnel->parms.iph;
668 struct ipv6hdr *iph6 = ipv6_hdr(skb);
669 u8 tos = tunnel->parms.iph.tos;
670 __be16 df = tiph->frag_off;
671 struct rtable *rt; /* Route to the other host */
672 struct net_device *tdev; /* Device to other host */
673 struct iphdr *iph; /* Our new IP header */
674 unsigned int max_headroom; /* The extra header space needed */
675 __be32 dst = tiph->daddr;
676 int mtu;
677 struct in6_addr *addr6;
678 int addr_type;
679
680 if (skb->protocol != htons(ETH_P_IPV6))
681 goto tx_error;
682
683 /* ISATAP (RFC4214) - must come before 6to4 */
684 if (dev->priv_flags & IFF_ISATAP) {
685 struct neighbour *neigh = NULL;
686
687 if (skb_dst(skb))
688 neigh = skb_dst(skb)->neighbour;
689
690 if (neigh == NULL) {
691 if (net_ratelimit())
692 printk(KERN_DEBUG "sit: nexthop == NULL\n");
693 goto tx_error;
694 }
695
696 addr6 = (struct in6_addr*)&neigh->primary_key;
697 addr_type = ipv6_addr_type(addr6);
698
699 if ((addr_type & IPV6_ADDR_UNICAST) &&
700 ipv6_addr_is_isatap(addr6))
701 dst = addr6->s6_addr32[3];
702 else
703 goto tx_error;
704 }
705
706 if (!dst)
707 dst = try_6rd(&iph6->daddr, tunnel);
708
709 if (!dst) {
710 struct neighbour *neigh = NULL;
711
712 if (skb_dst(skb))
713 neigh = skb_dst(skb)->neighbour;
714
715 if (neigh == NULL) {
716 if (net_ratelimit())
717 printk(KERN_DEBUG "sit: nexthop == NULL\n");
718 goto tx_error;
719 }
720
721 addr6 = (struct in6_addr*)&neigh->primary_key;
722 addr_type = ipv6_addr_type(addr6);
723
724 if (addr_type == IPV6_ADDR_ANY) {
725 addr6 = &ipv6_hdr(skb)->daddr;
726 addr_type = ipv6_addr_type(addr6);
727 }
728
729 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
730 goto tx_error_icmp;
731
732 dst = addr6->s6_addr32[3];
733 }
734
735 rt = ip_route_output_ports(dev_net(dev), NULL,
736 dst, tiph->saddr,
737 0, 0,
738 IPPROTO_IPV6, RT_TOS(tos),
739 tunnel->parms.link);
740 if (IS_ERR(rt)) {
741 dev->stats.tx_carrier_errors++;
742 goto tx_error_icmp;
743 }
744 if (rt->rt_type != RTN_UNICAST) {
745 ip_rt_put(rt);
746 dev->stats.tx_carrier_errors++;
747 goto tx_error_icmp;
748 }
749 tdev = rt->dst.dev;
750
751 if (tdev == dev) {
752 ip_rt_put(rt);
753 dev->stats.collisions++;
754 goto tx_error;
755 }
756
757 if (df) {
758 mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr);
759
760 if (mtu < 68) {
761 dev->stats.collisions++;
762 ip_rt_put(rt);
763 goto tx_error;
764 }
765
766 if (mtu < IPV6_MIN_MTU) {
767 mtu = IPV6_MIN_MTU;
768 df = 0;
769 }
770
771 if (tunnel->parms.iph.daddr && skb_dst(skb))
772 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
773
774 if (skb->len > mtu) {
775 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
776 ip_rt_put(rt);
777 goto tx_error;
778 }
779 }
780
781 if (tunnel->err_count > 0) {
782 if (time_before(jiffies,
783 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
784 tunnel->err_count--;
785 dst_link_failure(skb);
786 } else
787 tunnel->err_count = 0;
788 }
789
790 /*
791 * Okay, now see if we can stuff it in the buffer as-is.
792 */
793 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
794
795 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
796 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
797 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
798 if (!new_skb) {
799 ip_rt_put(rt);
800 dev->stats.tx_dropped++;
801 dev_kfree_skb(skb);
802 return NETDEV_TX_OK;
803 }
804 if (skb->sk)
805 skb_set_owner_w(new_skb, skb->sk);
806 dev_kfree_skb(skb);
807 skb = new_skb;
808 iph6 = ipv6_hdr(skb);
809 }
810
811 skb->transport_header = skb->network_header;
812 skb_push(skb, sizeof(struct iphdr));
813 skb_reset_network_header(skb);
814 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
815 IPCB(skb)->flags = 0;
816 skb_dst_drop(skb);
817 skb_dst_set(skb, &rt->dst);
818
819 /*
820 * Push down and install the IPIP header.
821 */
822
823 iph = ip_hdr(skb);
824 iph->version = 4;
825 iph->ihl = sizeof(struct iphdr)>>2;
826 iph->frag_off = df;
827 iph->protocol = IPPROTO_IPV6;
828 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
829 iph->daddr = rt->rt_dst;
830 iph->saddr = rt->rt_src;
831
832 if ((iph->ttl = tiph->ttl) == 0)
833 iph->ttl = iph6->hop_limit;
834
835 nf_reset(skb);
836 tstats = this_cpu_ptr(dev->tstats);
837 __IPTUNNEL_XMIT(tstats, &dev->stats);
838 return NETDEV_TX_OK;
839
840 tx_error_icmp:
841 dst_link_failure(skb);
842 tx_error:
843 dev->stats.tx_errors++;
844 dev_kfree_skb(skb);
845 return NETDEV_TX_OK;
846 }
847
848 static void ipip6_tunnel_bind_dev(struct net_device *dev)
849 {
850 struct net_device *tdev = NULL;
851 struct ip_tunnel *tunnel;
852 struct iphdr *iph;
853
854 tunnel = netdev_priv(dev);
855 iph = &tunnel->parms.iph;
856
857 if (iph->daddr) {
858 struct rtable *rt = ip_route_output_ports(dev_net(dev), NULL,
859 iph->daddr, iph->saddr,
860 0, 0,
861 IPPROTO_IPV6,
862 RT_TOS(iph->tos),
863 tunnel->parms.link);
864
865 if (!IS_ERR(rt)) {
866 tdev = rt->dst.dev;
867 ip_rt_put(rt);
868 }
869 dev->flags |= IFF_POINTOPOINT;
870 }
871
872 if (!tdev && tunnel->parms.link)
873 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
874
875 if (tdev) {
876 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
877 dev->mtu = tdev->mtu - sizeof(struct iphdr);
878 if (dev->mtu < IPV6_MIN_MTU)
879 dev->mtu = IPV6_MIN_MTU;
880 }
881 dev->iflink = tunnel->parms.link;
882 }
883
884 static int
885 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
886 {
887 int err = 0;
888 struct ip_tunnel_parm p;
889 struct ip_tunnel_prl prl;
890 struct ip_tunnel *t;
891 struct net *net = dev_net(dev);
892 struct sit_net *sitn = net_generic(net, sit_net_id);
893 #ifdef CONFIG_IPV6_SIT_6RD
894 struct ip_tunnel_6rd ip6rd;
895 #endif
896
897 switch (cmd) {
898 case SIOCGETTUNNEL:
899 #ifdef CONFIG_IPV6_SIT_6RD
900 case SIOCGET6RD:
901 #endif
902 t = NULL;
903 if (dev == sitn->fb_tunnel_dev) {
904 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
905 err = -EFAULT;
906 break;
907 }
908 t = ipip6_tunnel_locate(net, &p, 0);
909 }
910 if (t == NULL)
911 t = netdev_priv(dev);
912
913 err = -EFAULT;
914 if (cmd == SIOCGETTUNNEL) {
915 memcpy(&p, &t->parms, sizeof(p));
916 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
917 sizeof(p)))
918 goto done;
919 #ifdef CONFIG_IPV6_SIT_6RD
920 } else {
921 ipv6_addr_copy(&ip6rd.prefix, &t->ip6rd.prefix);
922 ip6rd.relay_prefix = t->ip6rd.relay_prefix;
923 ip6rd.prefixlen = t->ip6rd.prefixlen;
924 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
925 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
926 sizeof(ip6rd)))
927 goto done;
928 #endif
929 }
930 err = 0;
931 break;
932
933 case SIOCADDTUNNEL:
934 case SIOCCHGTUNNEL:
935 err = -EPERM;
936 if (!capable(CAP_NET_ADMIN))
937 goto done;
938
939 err = -EFAULT;
940 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
941 goto done;
942
943 err = -EINVAL;
944 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
945 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
946 goto done;
947 if (p.iph.ttl)
948 p.iph.frag_off |= htons(IP_DF);
949
950 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
951
952 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
953 if (t != NULL) {
954 if (t->dev != dev) {
955 err = -EEXIST;
956 break;
957 }
958 } else {
959 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
960 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
961 err = -EINVAL;
962 break;
963 }
964 t = netdev_priv(dev);
965 ipip6_tunnel_unlink(sitn, t);
966 synchronize_net();
967 t->parms.iph.saddr = p.iph.saddr;
968 t->parms.iph.daddr = p.iph.daddr;
969 memcpy(dev->dev_addr, &p.iph.saddr, 4);
970 memcpy(dev->broadcast, &p.iph.daddr, 4);
971 ipip6_tunnel_link(sitn, t);
972 netdev_state_change(dev);
973 }
974 }
975
976 if (t) {
977 err = 0;
978 if (cmd == SIOCCHGTUNNEL) {
979 t->parms.iph.ttl = p.iph.ttl;
980 t->parms.iph.tos = p.iph.tos;
981 if (t->parms.link != p.link) {
982 t->parms.link = p.link;
983 ipip6_tunnel_bind_dev(dev);
984 netdev_state_change(dev);
985 }
986 }
987 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
988 err = -EFAULT;
989 } else
990 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
991 break;
992
993 case SIOCDELTUNNEL:
994 err = -EPERM;
995 if (!capable(CAP_NET_ADMIN))
996 goto done;
997
998 if (dev == sitn->fb_tunnel_dev) {
999 err = -EFAULT;
1000 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1001 goto done;
1002 err = -ENOENT;
1003 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
1004 goto done;
1005 err = -EPERM;
1006 if (t == netdev_priv(sitn->fb_tunnel_dev))
1007 goto done;
1008 dev = t->dev;
1009 }
1010 unregister_netdevice(dev);
1011 err = 0;
1012 break;
1013
1014 case SIOCGETPRL:
1015 err = -EINVAL;
1016 if (dev == sitn->fb_tunnel_dev)
1017 goto done;
1018 err = -ENOENT;
1019 if (!(t = netdev_priv(dev)))
1020 goto done;
1021 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
1022 break;
1023
1024 case SIOCADDPRL:
1025 case SIOCDELPRL:
1026 case SIOCCHGPRL:
1027 err = -EPERM;
1028 if (!capable(CAP_NET_ADMIN))
1029 goto done;
1030 err = -EINVAL;
1031 if (dev == sitn->fb_tunnel_dev)
1032 goto done;
1033 err = -EFAULT;
1034 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
1035 goto done;
1036 err = -ENOENT;
1037 if (!(t = netdev_priv(dev)))
1038 goto done;
1039
1040 switch (cmd) {
1041 case SIOCDELPRL:
1042 err = ipip6_tunnel_del_prl(t, &prl);
1043 break;
1044 case SIOCADDPRL:
1045 case SIOCCHGPRL:
1046 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
1047 break;
1048 }
1049 netdev_state_change(dev);
1050 break;
1051
1052 #ifdef CONFIG_IPV6_SIT_6RD
1053 case SIOCADD6RD:
1054 case SIOCCHG6RD:
1055 case SIOCDEL6RD:
1056 err = -EPERM;
1057 if (!capable(CAP_NET_ADMIN))
1058 goto done;
1059
1060 err = -EFAULT;
1061 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
1062 sizeof(ip6rd)))
1063 goto done;
1064
1065 t = netdev_priv(dev);
1066
1067 if (cmd != SIOCDEL6RD) {
1068 struct in6_addr prefix;
1069 __be32 relay_prefix;
1070
1071 err = -EINVAL;
1072 if (ip6rd.relay_prefixlen > 32 ||
1073 ip6rd.prefixlen + (32 - ip6rd.relay_prefixlen) > 64)
1074 goto done;
1075
1076 ipv6_addr_prefix(&prefix, &ip6rd.prefix,
1077 ip6rd.prefixlen);
1078 if (!ipv6_addr_equal(&prefix, &ip6rd.prefix))
1079 goto done;
1080 if (ip6rd.relay_prefixlen)
1081 relay_prefix = ip6rd.relay_prefix &
1082 htonl(0xffffffffUL <<
1083 (32 - ip6rd.relay_prefixlen));
1084 else
1085 relay_prefix = 0;
1086 if (relay_prefix != ip6rd.relay_prefix)
1087 goto done;
1088
1089 ipv6_addr_copy(&t->ip6rd.prefix, &prefix);
1090 t->ip6rd.relay_prefix = relay_prefix;
1091 t->ip6rd.prefixlen = ip6rd.prefixlen;
1092 t->ip6rd.relay_prefixlen = ip6rd.relay_prefixlen;
1093 } else
1094 ipip6_tunnel_clone_6rd(dev, sitn);
1095
1096 err = 0;
1097 break;
1098 #endif
1099
1100 default:
1101 err = -EINVAL;
1102 }
1103
1104 done:
1105 return err;
1106 }
1107
1108 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1109 {
1110 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
1111 return -EINVAL;
1112 dev->mtu = new_mtu;
1113 return 0;
1114 }
1115
1116 static const struct net_device_ops ipip6_netdev_ops = {
1117 .ndo_uninit = ipip6_tunnel_uninit,
1118 .ndo_start_xmit = ipip6_tunnel_xmit,
1119 .ndo_do_ioctl = ipip6_tunnel_ioctl,
1120 .ndo_change_mtu = ipip6_tunnel_change_mtu,
1121 .ndo_get_stats = ipip6_get_stats,
1122 };
1123
1124 static void ipip6_dev_free(struct net_device *dev)
1125 {
1126 free_percpu(dev->tstats);
1127 free_netdev(dev);
1128 }
1129
1130 static void ipip6_tunnel_setup(struct net_device *dev)
1131 {
1132 dev->netdev_ops = &ipip6_netdev_ops;
1133 dev->destructor = ipip6_dev_free;
1134
1135 dev->type = ARPHRD_SIT;
1136 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
1137 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
1138 dev->flags = IFF_NOARP;
1139 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1140 dev->iflink = 0;
1141 dev->addr_len = 4;
1142 dev->features |= NETIF_F_NETNS_LOCAL;
1143 dev->features |= NETIF_F_LLTX;
1144 }
1145
1146 static int ipip6_tunnel_init(struct net_device *dev)
1147 {
1148 struct ip_tunnel *tunnel = netdev_priv(dev);
1149
1150 tunnel->dev = dev;
1151 strcpy(tunnel->parms.name, dev->name);
1152
1153 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
1154 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
1155
1156 ipip6_tunnel_bind_dev(dev);
1157 dev->tstats = alloc_percpu(struct pcpu_tstats);
1158 if (!dev->tstats)
1159 return -ENOMEM;
1160
1161 return 0;
1162 }
1163
1164 static int __net_init ipip6_fb_tunnel_init(struct net_device *dev)
1165 {
1166 struct ip_tunnel *tunnel = netdev_priv(dev);
1167 struct iphdr *iph = &tunnel->parms.iph;
1168 struct net *net = dev_net(dev);
1169 struct sit_net *sitn = net_generic(net, sit_net_id);
1170
1171 tunnel->dev = dev;
1172 strcpy(tunnel->parms.name, dev->name);
1173
1174 iph->version = 4;
1175 iph->protocol = IPPROTO_IPV6;
1176 iph->ihl = 5;
1177 iph->ttl = 64;
1178
1179 dev->tstats = alloc_percpu(struct pcpu_tstats);
1180 if (!dev->tstats)
1181 return -ENOMEM;
1182 dev_hold(dev);
1183 rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
1184 return 0;
1185 }
1186
1187 static struct xfrm_tunnel sit_handler __read_mostly = {
1188 .handler = ipip6_rcv,
1189 .err_handler = ipip6_err,
1190 .priority = 1,
1191 };
1192
1193 static void __net_exit sit_destroy_tunnels(struct sit_net *sitn, struct list_head *head)
1194 {
1195 int prio;
1196
1197 for (prio = 1; prio < 4; prio++) {
1198 int h;
1199 for (h = 0; h < HASH_SIZE; h++) {
1200 struct ip_tunnel *t;
1201
1202 t = rtnl_dereference(sitn->tunnels[prio][h]);
1203 while (t != NULL) {
1204 unregister_netdevice_queue(t->dev, head);
1205 t = rtnl_dereference(t->next);
1206 }
1207 }
1208 }
1209 }
1210
1211 static int __net_init sit_init_net(struct net *net)
1212 {
1213 struct sit_net *sitn = net_generic(net, sit_net_id);
1214 int err;
1215
1216 sitn->tunnels[0] = sitn->tunnels_wc;
1217 sitn->tunnels[1] = sitn->tunnels_l;
1218 sitn->tunnels[2] = sitn->tunnels_r;
1219 sitn->tunnels[3] = sitn->tunnels_r_l;
1220
1221 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1222 ipip6_tunnel_setup);
1223 if (!sitn->fb_tunnel_dev) {
1224 err = -ENOMEM;
1225 goto err_alloc_dev;
1226 }
1227 dev_net_set(sitn->fb_tunnel_dev, net);
1228
1229 err = ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
1230 if (err)
1231 goto err_dev_free;
1232
1233 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
1234
1235 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1236 goto err_reg_dev;
1237
1238 return 0;
1239
1240 err_reg_dev:
1241 dev_put(sitn->fb_tunnel_dev);
1242 err_dev_free:
1243 ipip6_dev_free(sitn->fb_tunnel_dev);
1244 err_alloc_dev:
1245 return err;
1246 }
1247
1248 static void __net_exit sit_exit_net(struct net *net)
1249 {
1250 struct sit_net *sitn = net_generic(net, sit_net_id);
1251 LIST_HEAD(list);
1252
1253 rtnl_lock();
1254 sit_destroy_tunnels(sitn, &list);
1255 unregister_netdevice_queue(sitn->fb_tunnel_dev, &list);
1256 unregister_netdevice_many(&list);
1257 rtnl_unlock();
1258 }
1259
1260 static struct pernet_operations sit_net_ops = {
1261 .init = sit_init_net,
1262 .exit = sit_exit_net,
1263 .id = &sit_net_id,
1264 .size = sizeof(struct sit_net),
1265 };
1266
1267 static void __exit sit_cleanup(void)
1268 {
1269 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1270
1271 unregister_pernet_device(&sit_net_ops);
1272 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1273 }
1274
1275 static int __init sit_init(void)
1276 {
1277 int err;
1278
1279 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
1280
1281 err = register_pernet_device(&sit_net_ops);
1282 if (err < 0)
1283 return err;
1284 err = xfrm4_tunnel_register(&sit_handler, AF_INET6);
1285 if (err < 0) {
1286 unregister_pernet_device(&sit_net_ops);
1287 printk(KERN_INFO "sit init: Can't add protocol\n");
1288 }
1289 return err;
1290 }
1291
1292 module_init(sit_init);
1293 module_exit(sit_cleanup);
1294 MODULE_LICENSE("GPL");
1295 MODULE_ALIAS_NETDEV("sit0");
CRIS linux kernel tree