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Linux 2.6.26-rc5
[linux-2.6/openmoko-kernel/knife-kernel.git] / net / ipv6 / sit.c
blob3de6ffdaedf2ff234a2f16ddaaacce7e4a481aef
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 * $Id: sit.c,v 1.53 2001/09/25 05:09:53 davem Exp $
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 *
16 * Changes:
17 * Roger Venning <r.venning@telstra.com>: 6to4 support
18 * Nate Thompson <nate@thebog.net>: 6to4 support
19 * Fred Templin <fred.l.templin@boeing.com>: isatap support
20 */
21
22 #include <linux/module.h>
23 #include <linux/capability.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/in6.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_arp.h>
32 #include <linux/icmp.h>
33 #include <asm/uaccess.h>
34 #include <linux/init.h>
35 #include <linux/netfilter_ipv4.h>
36 #include <linux/if_ether.h>
37
38 #include <net/sock.h>
39 #include <net/snmp.h>
40
41 #include <net/ipv6.h>
42 #include <net/protocol.h>
43 #include <net/transp_v6.h>
44 #include <net/ip6_fib.h>
45 #include <net/ip6_route.h>
46 #include <net/ndisc.h>
47 #include <net/addrconf.h>
48 #include <net/ip.h>
49 #include <net/udp.h>
50 #include <net/icmp.h>
51 #include <net/ipip.h>
52 #include <net/inet_ecn.h>
53 #include <net/xfrm.h>
54 #include <net/dsfield.h>
55 #include <net/net_namespace.h>
56 #include <net/netns/generic.h>
57
58 /*
59 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
60
61 For comments look at net/ipv4/ip_gre.c --ANK
62 */
63
64 #define HASH_SIZE 16
65 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
66
67 static int ipip6_fb_tunnel_init(struct net_device *dev);
68 static int ipip6_tunnel_init(struct net_device *dev);
69 static void ipip6_tunnel_setup(struct net_device *dev);
70
71 static int sit_net_id;
72 struct sit_net {
73 struct ip_tunnel *tunnels_r_l[HASH_SIZE];
74 struct ip_tunnel *tunnels_r[HASH_SIZE];
75 struct ip_tunnel *tunnels_l[HASH_SIZE];
76 struct ip_tunnel *tunnels_wc[1];
77 struct ip_tunnel **tunnels[4];
78
79 struct net_device *fb_tunnel_dev;
80 };
81
82 static DEFINE_RWLOCK(ipip6_lock);
83
84 static struct ip_tunnel * ipip6_tunnel_lookup(struct net *net,
85 __be32 remote, __be32 local)
86 {
87 unsigned h0 = HASH(remote);
88 unsigned h1 = HASH(local);
89 struct ip_tunnel *t;
90 struct sit_net *sitn = net_generic(net, sit_net_id);
91
92 for (t = sitn->tunnels_r_l[h0^h1]; t; t = t->next) {
93 if (local == t->parms.iph.saddr &&
94 remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
95 return t;
96 }
97 for (t = sitn->tunnels_r[h0]; t; t = t->next) {
98 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
99 return t;
100 }
101 for (t = sitn->tunnels_l[h1]; t; t = t->next) {
102 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
103 return t;
104 }
105 if ((t = sitn->tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
106 return t;
107 return NULL;
108 }
109
110 static struct ip_tunnel **__ipip6_bucket(struct sit_net *sitn,
111 struct ip_tunnel_parm *parms)
112 {
113 __be32 remote = parms->iph.daddr;
114 __be32 local = parms->iph.saddr;
115 unsigned h = 0;
116 int prio = 0;
117
118 if (remote) {
119 prio |= 2;
120 h ^= HASH(remote);
121 }
122 if (local) {
123 prio |= 1;
124 h ^= HASH(local);
125 }
126 return &sitn->tunnels[prio][h];
127 }
128
129 static inline struct ip_tunnel **ipip6_bucket(struct sit_net *sitn,
130 struct ip_tunnel *t)
131 {
132 return __ipip6_bucket(sitn, &t->parms);
133 }
134
135 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
136 {
137 struct ip_tunnel **tp;
138
139 for (tp = ipip6_bucket(sitn, t); *tp; tp = &(*tp)->next) {
140 if (t == *tp) {
141 write_lock_bh(&ipip6_lock);
142 *tp = t->next;
143 write_unlock_bh(&ipip6_lock);
144 break;
145 }
146 }
147 }
148
149 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
150 {
151 struct ip_tunnel **tp = ipip6_bucket(sitn, t);
152
153 t->next = *tp;
154 write_lock_bh(&ipip6_lock);
155 *tp = t;
156 write_unlock_bh(&ipip6_lock);
157 }
158
159 static struct ip_tunnel * ipip6_tunnel_locate(struct net *net,
160 struct ip_tunnel_parm *parms, int create)
161 {
162 __be32 remote = parms->iph.daddr;
163 __be32 local = parms->iph.saddr;
164 struct ip_tunnel *t, **tp, *nt;
165 struct net_device *dev;
166 char name[IFNAMSIZ];
167 struct sit_net *sitn = net_generic(net, sit_net_id);
168
169 for (tp = __ipip6_bucket(sitn, parms); (t = *tp) != NULL; tp = &t->next) {
170 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
171 return t;
172 }
173 if (!create)
174 goto failed;
175
176 if (parms->name[0])
177 strlcpy(name, parms->name, IFNAMSIZ);
178 else
179 sprintf(name, "sit%%d");
180
181 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
182 if (dev == NULL)
183 return NULL;
184
185 dev_net_set(dev, net);
186
187 if (strchr(name, '%')) {
188 if (dev_alloc_name(dev, name) < 0)
189 goto failed_free;
190 }
191
192 nt = netdev_priv(dev);
193 dev->init = ipip6_tunnel_init;
194 nt->parms = *parms;
195
196 if (parms->i_flags & SIT_ISATAP)
197 dev->priv_flags |= IFF_ISATAP;
198
199 if (register_netdevice(dev) < 0)
200 goto failed_free;
201
202 dev_hold(dev);
203
204 ipip6_tunnel_link(sitn, nt);
205 return nt;
206
207 failed_free:
208 free_netdev(dev);
209 failed:
210 return NULL;
211 }
212
213 static struct ip_tunnel_prl_entry *
214 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
215 {
216 struct ip_tunnel_prl_entry *p = (struct ip_tunnel_prl_entry *)NULL;
217
218 for (p = t->prl; p; p = p->next)
219 if (p->addr == addr)
220 break;
221 return p;
222
223 }
224
225 static int ipip6_tunnel_get_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
226 {
227 struct ip_tunnel_prl *kp;
228 struct ip_tunnel_prl_entry *prl;
229 unsigned int cmax, c = 0, ca, len;
230 int ret = 0;
231
232 cmax = a->datalen / sizeof(*a);
233 if (cmax > 1 && a->addr != htonl(INADDR_ANY))
234 cmax = 1;
235
236 /* For simple GET or for root users,
237 * we try harder to allocate.
238 */
239 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
240 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
241 NULL;
242
243 read_lock(&ipip6_lock);
244
245 ca = t->prl_count < cmax ? t->prl_count : cmax;
246
247 if (!kp) {
248 /* We don't try hard to allocate much memory for
249 * non-root users.
250 * For root users, retry allocating enough memory for
251 * the answer.
252 */
253 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
254 if (!kp) {
255 ret = -ENOMEM;
256 goto out;
257 }
258 }
259
260 c = 0;
261 for (prl = t->prl; prl; prl = prl->next) {
262 if (c > cmax)
263 break;
264 if (a->addr != htonl(INADDR_ANY) && prl->addr != a->addr)
265 continue;
266 kp[c].addr = prl->addr;
267 kp[c].flags = prl->flags;
268 c++;
269 if (a->addr != htonl(INADDR_ANY))
270 break;
271 }
272 out:
273 read_unlock(&ipip6_lock);
274
275 len = sizeof(*kp) * c;
276 ret = len ? copy_to_user(a->data, kp, len) : 0;
277
278 kfree(kp);
279 if (ret)
280 return -EFAULT;
281
282 a->datalen = len;
283 return 0;
284 }
285
286 static int
287 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
288 {
289 struct ip_tunnel_prl_entry *p;
290 int err = 0;
291
292 if (a->addr == htonl(INADDR_ANY))
293 return -EINVAL;
294
295 write_lock(&ipip6_lock);
296
297 for (p = t->prl; p; p = p->next) {
298 if (p->addr == a->addr) {
299 if (chg)
300 goto update;
301 err = -EEXIST;
302 goto out;
303 }
304 }
305
306 if (chg) {
307 err = -ENXIO;
308 goto out;
309 }
310
311 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
312 if (!p) {
313 err = -ENOBUFS;
314 goto out;
315 }
316
317 p->next = t->prl;
318 t->prl = p;
319 t->prl_count++;
320 update:
321 p->addr = a->addr;
322 p->flags = a->flags;
323 out:
324 write_unlock(&ipip6_lock);
325 return err;
326 }
327
328 static int
329 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
330 {
331 struct ip_tunnel_prl_entry *x, **p;
332 int err = 0;
333
334 write_lock(&ipip6_lock);
335
336 if (a && a->addr != htonl(INADDR_ANY)) {
337 for (p = &t->prl; *p; p = &(*p)->next) {
338 if ((*p)->addr == a->addr) {
339 x = *p;
340 *p = x->next;
341 kfree(x);
342 t->prl_count--;
343 goto out;
344 }
345 }
346 err = -ENXIO;
347 } else {
348 while (t->prl) {
349 x = t->prl;
350 t->prl = t->prl->next;
351 kfree(x);
352 t->prl_count--;
353 }
354 }
355 out:
356 write_unlock(&ipip6_lock);
357 return 0;
358 }
359
360 static int
361 isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
362 {
363 struct ip_tunnel_prl_entry *p;
364 int ok = 1;
365
366 read_lock(&ipip6_lock);
367 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
368 if (p) {
369 if (p->flags & PRL_DEFAULT)
370 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
371 else
372 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
373 } else {
374 struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
375 if (ipv6_addr_is_isatap(addr6) &&
376 (addr6->s6_addr32[3] == iph->saddr) &&
377 ipv6_chk_prefix(addr6, t->dev))
378 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
379 else
380 ok = 0;
381 }
382 read_unlock(&ipip6_lock);
383 return ok;
384 }
385
386 static void ipip6_tunnel_uninit(struct net_device *dev)
387 {
388 struct net *net = dev_net(dev);
389 struct sit_net *sitn = net_generic(net, sit_net_id);
390
391 if (dev == sitn->fb_tunnel_dev) {
392 write_lock_bh(&ipip6_lock);
393 sitn->tunnels_wc[0] = NULL;
394 write_unlock_bh(&ipip6_lock);
395 dev_put(dev);
396 } else {
397 ipip6_tunnel_unlink(sitn, netdev_priv(dev));
398 ipip6_tunnel_del_prl(netdev_priv(dev), NULL);
399 dev_put(dev);
400 }
401 }
402
403
404 static int ipip6_err(struct sk_buff *skb, u32 info)
405 {
406
407 /* All the routers (except for Linux) return only
408 8 bytes of packet payload. It means, that precise relaying of
409 ICMP in the real Internet is absolutely infeasible.
410 */
411 struct iphdr *iph = (struct iphdr*)skb->data;
412 const int type = icmp_hdr(skb)->type;
413 const int code = icmp_hdr(skb)->code;
414 struct ip_tunnel *t;
415 int err;
416
417 switch (type) {
418 default:
419 case ICMP_PARAMETERPROB:
420 return 0;
421
422 case ICMP_DEST_UNREACH:
423 switch (code) {
424 case ICMP_SR_FAILED:
425 case ICMP_PORT_UNREACH:
426 /* Impossible event. */
427 return 0;
428 case ICMP_FRAG_NEEDED:
429 /* Soft state for pmtu is maintained by IP core. */
430 return 0;
431 default:
432 /* All others are translated to HOST_UNREACH.
433 rfc2003 contains "deep thoughts" about NET_UNREACH,
434 I believe they are just ether pollution. --ANK
435 */
436 break;
437 }
438 break;
439 case ICMP_TIME_EXCEEDED:
440 if (code != ICMP_EXC_TTL)
441 return 0;
442 break;
443 }
444
445 err = -ENOENT;
446
447 read_lock(&ipip6_lock);
448 t = ipip6_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
449 if (t == NULL || t->parms.iph.daddr == 0)
450 goto out;
451
452 err = 0;
453 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
454 goto out;
455
456 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
457 t->err_count++;
458 else
459 t->err_count = 1;
460 t->err_time = jiffies;
461 out:
462 read_unlock(&ipip6_lock);
463 return err;
464 }
465
466 static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
467 {
468 if (INET_ECN_is_ce(iph->tos))
469 IP6_ECN_set_ce(ipv6_hdr(skb));
470 }
471
472 static int ipip6_rcv(struct sk_buff *skb)
473 {
474 struct iphdr *iph;
475 struct ip_tunnel *tunnel;
476
477 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
478 goto out;
479
480 iph = ip_hdr(skb);
481
482 read_lock(&ipip6_lock);
483 if ((tunnel = ipip6_tunnel_lookup(dev_net(skb->dev),
484 iph->saddr, iph->daddr)) != NULL) {
485 secpath_reset(skb);
486 skb->mac_header = skb->network_header;
487 skb_reset_network_header(skb);
488 IPCB(skb)->flags = 0;
489 skb->protocol = htons(ETH_P_IPV6);
490 skb->pkt_type = PACKET_HOST;
491
492 if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
493 !isatap_chksrc(skb, iph, tunnel)) {
494 tunnel->stat.rx_errors++;
495 read_unlock(&ipip6_lock);
496 kfree_skb(skb);
497 return 0;
498 }
499 tunnel->stat.rx_packets++;
500 tunnel->stat.rx_bytes += skb->len;
501 skb->dev = tunnel->dev;
502 dst_release(skb->dst);
503 skb->dst = NULL;
504 nf_reset(skb);
505 ipip6_ecn_decapsulate(iph, skb);
506 netif_rx(skb);
507 read_unlock(&ipip6_lock);
508 return 0;
509 }
510
511 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
512 read_unlock(&ipip6_lock);
513 out:
514 kfree_skb(skb);
515 return 0;
516 }
517
518 /* Returns the embedded IPv4 address if the IPv6 address
519 comes from 6to4 (RFC 3056) addr space */
520
521 static inline __be32 try_6to4(struct in6_addr *v6dst)
522 {
523 __be32 dst = 0;
524
525 if (v6dst->s6_addr16[0] == htons(0x2002)) {
526 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
527 memcpy(&dst, &v6dst->s6_addr16[1], 4);
528 }
529 return dst;
530 }
531
532 /*
533 * This function assumes it is being called from dev_queue_xmit()
534 * and that skb is filled properly by that function.
535 */
536
537 static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
538 {
539 struct ip_tunnel *tunnel = netdev_priv(dev);
540 struct net_device_stats *stats = &tunnel->stat;
541 struct iphdr *tiph = &tunnel->parms.iph;
542 struct ipv6hdr *iph6 = ipv6_hdr(skb);
543 u8 tos = tunnel->parms.iph.tos;
544 struct rtable *rt; /* Route to the other host */
545 struct net_device *tdev; /* Device to other host */
546 struct iphdr *iph; /* Our new IP header */
547 unsigned int max_headroom; /* The extra header space needed */
548 __be32 dst = tiph->daddr;
549 int mtu;
550 struct in6_addr *addr6;
551 int addr_type;
552
553 if (tunnel->recursion++) {
554 tunnel->stat.collisions++;
555 goto tx_error;
556 }
557
558 if (skb->protocol != htons(ETH_P_IPV6))
559 goto tx_error;
560
561 /* ISATAP (RFC4214) - must come before 6to4 */
562 if (dev->priv_flags & IFF_ISATAP) {
563 struct neighbour *neigh = NULL;
564
565 if (skb->dst)
566 neigh = skb->dst->neighbour;
567
568 if (neigh == NULL) {
569 if (net_ratelimit())
570 printk(KERN_DEBUG "sit: nexthop == NULL\n");
571 goto tx_error;
572 }
573
574 addr6 = (struct in6_addr*)&neigh->primary_key;
575 addr_type = ipv6_addr_type(addr6);
576
577 if ((addr_type & IPV6_ADDR_UNICAST) &&
578 ipv6_addr_is_isatap(addr6))
579 dst = addr6->s6_addr32[3];
580 else
581 goto tx_error;
582 }
583
584 if (!dst)
585 dst = try_6to4(&iph6->daddr);
586
587 if (!dst) {
588 struct neighbour *neigh = NULL;
589
590 if (skb->dst)
591 neigh = skb->dst->neighbour;
592
593 if (neigh == NULL) {
594 if (net_ratelimit())
595 printk(KERN_DEBUG "sit: nexthop == NULL\n");
596 goto tx_error;
597 }
598
599 addr6 = (struct in6_addr*)&neigh->primary_key;
600 addr_type = ipv6_addr_type(addr6);
601
602 if (addr_type == IPV6_ADDR_ANY) {
603 addr6 = &ipv6_hdr(skb)->daddr;
604 addr_type = ipv6_addr_type(addr6);
605 }
606
607 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
608 goto tx_error_icmp;
609
610 dst = addr6->s6_addr32[3];
611 }
612
613 {
614 struct flowi fl = { .nl_u = { .ip4_u =
615 { .daddr = dst,
616 .saddr = tiph->saddr,
617 .tos = RT_TOS(tos) } },
618 .oif = tunnel->parms.link,
619 .proto = IPPROTO_IPV6 };
620 if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
621 tunnel->stat.tx_carrier_errors++;
622 goto tx_error_icmp;
623 }
624 }
625 if (rt->rt_type != RTN_UNICAST) {
626 ip_rt_put(rt);
627 tunnel->stat.tx_carrier_errors++;
628 goto tx_error_icmp;
629 }
630 tdev = rt->u.dst.dev;
631
632 if (tdev == dev) {
633 ip_rt_put(rt);
634 tunnel->stat.collisions++;
635 goto tx_error;
636 }
637
638 if (tiph->frag_off)
639 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
640 else
641 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
642
643 if (mtu < 68) {
644 tunnel->stat.collisions++;
645 ip_rt_put(rt);
646 goto tx_error;
647 }
648 if (mtu < IPV6_MIN_MTU)
649 mtu = IPV6_MIN_MTU;
650 if (tunnel->parms.iph.daddr && skb->dst)
651 skb->dst->ops->update_pmtu(skb->dst, mtu);
652
653 if (skb->len > mtu) {
654 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
655 ip_rt_put(rt);
656 goto tx_error;
657 }
658
659 if (tunnel->err_count > 0) {
660 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
661 tunnel->err_count--;
662 dst_link_failure(skb);
663 } else
664 tunnel->err_count = 0;
665 }
666
667 /*
668 * Okay, now see if we can stuff it in the buffer as-is.
669 */
670 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
671
672 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
673 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
674 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
675 if (!new_skb) {
676 ip_rt_put(rt);
677 stats->tx_dropped++;
678 dev_kfree_skb(skb);
679 tunnel->recursion--;
680 return 0;
681 }
682 if (skb->sk)
683 skb_set_owner_w(new_skb, skb->sk);
684 dev_kfree_skb(skb);
685 skb = new_skb;
686 iph6 = ipv6_hdr(skb);
687 }
688
689 skb->transport_header = skb->network_header;
690 skb_push(skb, sizeof(struct iphdr));
691 skb_reset_network_header(skb);
692 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
693 IPCB(skb)->flags = 0;
694 dst_release(skb->dst);
695 skb->dst = &rt->u.dst;
696
697 /*
698 * Push down and install the IPIP header.
699 */
700
701 iph = ip_hdr(skb);
702 iph->version = 4;
703 iph->ihl = sizeof(struct iphdr)>>2;
704 if (mtu > IPV6_MIN_MTU)
705 iph->frag_off = htons(IP_DF);
706 else
707 iph->frag_off = 0;
708
709 iph->protocol = IPPROTO_IPV6;
710 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
711 iph->daddr = rt->rt_dst;
712 iph->saddr = rt->rt_src;
713
714 if ((iph->ttl = tiph->ttl) == 0)
715 iph->ttl = iph6->hop_limit;
716
717 nf_reset(skb);
718
719 IPTUNNEL_XMIT();
720 tunnel->recursion--;
721 return 0;
722
723 tx_error_icmp:
724 dst_link_failure(skb);
725 tx_error:
726 stats->tx_errors++;
727 dev_kfree_skb(skb);
728 tunnel->recursion--;
729 return 0;
730 }
731
732 static void ipip6_tunnel_bind_dev(struct net_device *dev)
733 {
734 struct net_device *tdev = NULL;
735 struct ip_tunnel *tunnel;
736 struct iphdr *iph;
737
738 tunnel = netdev_priv(dev);
739 iph = &tunnel->parms.iph;
740
741 if (iph->daddr) {
742 struct flowi fl = { .nl_u = { .ip4_u =
743 { .daddr = iph->daddr,
744 .saddr = iph->saddr,
745 .tos = RT_TOS(iph->tos) } },
746 .oif = tunnel->parms.link,
747 .proto = IPPROTO_IPV6 };
748 struct rtable *rt;
749 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
750 tdev = rt->u.dst.dev;
751 ip_rt_put(rt);
752 }
753 dev->flags |= IFF_POINTOPOINT;
754 }
755
756 if (!tdev && tunnel->parms.link)
757 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
758
759 if (tdev) {
760 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
761 dev->mtu = tdev->mtu - sizeof(struct iphdr);
762 if (dev->mtu < IPV6_MIN_MTU)
763 dev->mtu = IPV6_MIN_MTU;
764 }
765 dev->iflink = tunnel->parms.link;
766 }
767
768 static int
769 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
770 {
771 int err = 0;
772 struct ip_tunnel_parm p;
773 struct ip_tunnel_prl prl;
774 struct ip_tunnel *t;
775 struct net *net = dev_net(dev);
776 struct sit_net *sitn = net_generic(net, sit_net_id);
777
778 switch (cmd) {
779 case SIOCGETTUNNEL:
780 t = NULL;
781 if (dev == sitn->fb_tunnel_dev) {
782 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
783 err = -EFAULT;
784 break;
785 }
786 t = ipip6_tunnel_locate(net, &p, 0);
787 }
788 if (t == NULL)
789 t = netdev_priv(dev);
790 memcpy(&p, &t->parms, sizeof(p));
791 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
792 err = -EFAULT;
793 break;
794
795 case SIOCADDTUNNEL:
796 case SIOCCHGTUNNEL:
797 err = -EPERM;
798 if (!capable(CAP_NET_ADMIN))
799 goto done;
800
801 err = -EFAULT;
802 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
803 goto done;
804
805 err = -EINVAL;
806 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
807 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
808 goto done;
809 if (p.iph.ttl)
810 p.iph.frag_off |= htons(IP_DF);
811
812 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
813
814 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
815 if (t != NULL) {
816 if (t->dev != dev) {
817 err = -EEXIST;
818 break;
819 }
820 } else {
821 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
822 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
823 err = -EINVAL;
824 break;
825 }
826 t = netdev_priv(dev);
827 ipip6_tunnel_unlink(sitn, t);
828 t->parms.iph.saddr = p.iph.saddr;
829 t->parms.iph.daddr = p.iph.daddr;
830 memcpy(dev->dev_addr, &p.iph.saddr, 4);
831 memcpy(dev->broadcast, &p.iph.daddr, 4);
832 ipip6_tunnel_link(sitn, t);
833 netdev_state_change(dev);
834 }
835 }
836
837 if (t) {
838 err = 0;
839 if (cmd == SIOCCHGTUNNEL) {
840 t->parms.iph.ttl = p.iph.ttl;
841 t->parms.iph.tos = p.iph.tos;
842 if (t->parms.link != p.link) {
843 t->parms.link = p.link;
844 ipip6_tunnel_bind_dev(dev);
845 netdev_state_change(dev);
846 }
847 }
848 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
849 err = -EFAULT;
850 } else
851 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
852 break;
853
854 case SIOCDELTUNNEL:
855 err = -EPERM;
856 if (!capable(CAP_NET_ADMIN))
857 goto done;
858
859 if (dev == sitn->fb_tunnel_dev) {
860 err = -EFAULT;
861 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
862 goto done;
863 err = -ENOENT;
864 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
865 goto done;
866 err = -EPERM;
867 if (t == netdev_priv(sitn->fb_tunnel_dev))
868 goto done;
869 dev = t->dev;
870 }
871 unregister_netdevice(dev);
872 err = 0;
873 break;
874
875 case SIOCGETPRL:
876 case SIOCADDPRL:
877 case SIOCDELPRL:
878 case SIOCCHGPRL:
879 err = -EPERM;
880 if (cmd != SIOCGETPRL && !capable(CAP_NET_ADMIN))
881 goto done;
882 err = -EINVAL;
883 if (dev == sitn->fb_tunnel_dev)
884 goto done;
885 err = -EFAULT;
886 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
887 goto done;
888 err = -ENOENT;
889 if (!(t = netdev_priv(dev)))
890 goto done;
891
892 switch (cmd) {
893 case SIOCGETPRL:
894 err = ipip6_tunnel_get_prl(t, &prl);
895 if (!err && copy_to_user(ifr->ifr_ifru.ifru_data,
896 &prl, sizeof(prl)))
897 err = -EFAULT;
898 break;
899 case SIOCDELPRL:
900 err = ipip6_tunnel_del_prl(t, &prl);
901 break;
902 case SIOCADDPRL:
903 case SIOCCHGPRL:
904 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
905 break;
906 }
907 if (cmd != SIOCGETPRL)
908 netdev_state_change(dev);
909 break;
910
911 default:
912 err = -EINVAL;
913 }
914
915 done:
916 return err;
917 }
918
919 static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
920 {
921 return &(((struct ip_tunnel*)netdev_priv(dev))->stat);
922 }
923
924 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
925 {
926 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
927 return -EINVAL;
928 dev->mtu = new_mtu;
929 return 0;
930 }
931
932 static void ipip6_tunnel_setup(struct net_device *dev)
933 {
934 dev->uninit = ipip6_tunnel_uninit;
935 dev->destructor = free_netdev;
936 dev->hard_start_xmit = ipip6_tunnel_xmit;
937 dev->get_stats = ipip6_tunnel_get_stats;
938 dev->do_ioctl = ipip6_tunnel_ioctl;
939 dev->change_mtu = ipip6_tunnel_change_mtu;
940
941 dev->type = ARPHRD_SIT;
942 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
943 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
944 dev->flags = IFF_NOARP;
945 dev->iflink = 0;
946 dev->addr_len = 4;
947 dev->features |= NETIF_F_NETNS_LOCAL;
948 }
949
950 static int ipip6_tunnel_init(struct net_device *dev)
951 {
952 struct ip_tunnel *tunnel;
953
954 tunnel = netdev_priv(dev);
955
956 tunnel->dev = dev;
957 strcpy(tunnel->parms.name, dev->name);
958
959 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
960 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
961
962 ipip6_tunnel_bind_dev(dev);
963
964 return 0;
965 }
966
967 static int ipip6_fb_tunnel_init(struct net_device *dev)
968 {
969 struct ip_tunnel *tunnel = netdev_priv(dev);
970 struct iphdr *iph = &tunnel->parms.iph;
971 struct net *net = dev_net(dev);
972 struct sit_net *sitn = net_generic(net, sit_net_id);
973
974 tunnel->dev = dev;
975 strcpy(tunnel->parms.name, dev->name);
976
977 iph->version = 4;
978 iph->protocol = IPPROTO_IPV6;
979 iph->ihl = 5;
980 iph->ttl = 64;
981
982 dev_hold(dev);
983 sitn->tunnels_wc[0] = tunnel;
984 return 0;
985 }
986
987 static struct xfrm_tunnel sit_handler = {
988 .handler = ipip6_rcv,
989 .err_handler = ipip6_err,
990 .priority = 1,
991 };
992
993 static void sit_destroy_tunnels(struct sit_net *sitn)
994 {
995 int prio;
996
997 for (prio = 1; prio < 4; prio++) {
998 int h;
999 for (h = 0; h < HASH_SIZE; h++) {
1000 struct ip_tunnel *t;
1001 while ((t = sitn->tunnels[prio][h]) != NULL)
1002 unregister_netdevice(t->dev);
1003 }
1004 }
1005 }
1006
1007 static int sit_init_net(struct net *net)
1008 {
1009 int err;
1010 struct sit_net *sitn;
1011
1012 err = -ENOMEM;
1013 sitn = kzalloc(sizeof(struct sit_net), GFP_KERNEL);
1014 if (sitn == NULL)
1015 goto err_alloc;
1016
1017 err = net_assign_generic(net, sit_net_id, sitn);
1018 if (err < 0)
1019 goto err_assign;
1020
1021 sitn->tunnels[0] = sitn->tunnels_wc;
1022 sitn->tunnels[1] = sitn->tunnels_l;
1023 sitn->tunnels[2] = sitn->tunnels_r;
1024 sitn->tunnels[3] = sitn->tunnels_r_l;
1025
1026 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1027 ipip6_tunnel_setup);
1028 if (!sitn->fb_tunnel_dev) {
1029 err = -ENOMEM;
1030 goto err_alloc_dev;
1031 }
1032
1033 sitn->fb_tunnel_dev->init = ipip6_fb_tunnel_init;
1034 dev_net_set(sitn->fb_tunnel_dev, net);
1035
1036 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1037 goto err_reg_dev;
1038
1039 return 0;
1040
1041 err_reg_dev:
1042 free_netdev(sitn->fb_tunnel_dev);
1043 err_alloc_dev:
1044 /* nothing */
1045 err_assign:
1046 kfree(sitn);
1047 err_alloc:
1048 return err;
1049 }
1050
1051 static void sit_exit_net(struct net *net)
1052 {
1053 struct sit_net *sitn;
1054
1055 sitn = net_generic(net, sit_net_id);
1056 rtnl_lock();
1057 sit_destroy_tunnels(sitn);
1058 unregister_netdevice(sitn->fb_tunnel_dev);
1059 rtnl_unlock();
1060 kfree(sitn);
1061 }
1062
1063 static struct pernet_operations sit_net_ops = {
1064 .init = sit_init_net,
1065 .exit = sit_exit_net,
1066 };
1067
1068 static void __exit sit_cleanup(void)
1069 {
1070 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1071
1072 unregister_pernet_gen_device(sit_net_id, &sit_net_ops);
1073 }
1074
1075 static int __init sit_init(void)
1076 {
1077 int err;
1078
1079 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
1080
1081 if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) {
1082 printk(KERN_INFO "sit init: Can't add protocol\n");
1083 return -EAGAIN;
1084 }
1085
1086 err = register_pernet_gen_device(&sit_net_id, &sit_net_ops);
1087 if (err < 0)
1088 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1089
1090 return err;
1091 }
1092
1093 module_init(sit_init);
1094 module_exit(sit_cleanup);
1095 MODULE_LICENSE("GPL");
1096 MODULE_ALIAS("sit0");
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