Merge branches 'pxa-ian' and 'pxa-xm270' into pxa
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv6 / sit.c
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,
226 struct ip_tunnel_prl __user *a)
227 {
228 struct ip_tunnel_prl kprl, *kp;
229 struct ip_tunnel_prl_entry *prl;
230 unsigned int cmax, c = 0, ca, len;
231 int ret = 0;
232
233 if (copy_from_user(&kprl, a, sizeof(kprl)))
234 return -EFAULT;
235 cmax = kprl.datalen / sizeof(kprl);
236 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
237 cmax = 1;
238
239 /* For simple GET or for root users,
240 * we try harder to allocate.
241 */
242 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
243 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
244 NULL;
245
246 read_lock(&ipip6_lock);
247
248 ca = t->prl_count < cmax ? t->prl_count : cmax;
249
250 if (!kp) {
251 /* We don't try hard to allocate much memory for
252 * non-root users.
253 * For root users, retry allocating enough memory for
254 * the answer.
255 */
256 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
257 if (!kp) {
258 ret = -ENOMEM;
259 goto out;
260 }
261 }
262
263 c = 0;
264 for (prl = t->prl; prl; prl = prl->next) {
265 if (c > cmax)
266 break;
267 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
268 continue;
269 kp[c].addr = prl->addr;
270 kp[c].flags = prl->flags;
271 c++;
272 if (kprl.addr != htonl(INADDR_ANY))
273 break;
274 }
275 out:
276 read_unlock(&ipip6_lock);
277
278 len = sizeof(*kp) * c;
279 ret = 0;
280 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
281 ret = -EFAULT;
282
283 kfree(kp);
284
285 return ret;
286 }
287
288 static int
289 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
290 {
291 struct ip_tunnel_prl_entry *p;
292 int err = 0;
293
294 if (a->addr == htonl(INADDR_ANY))
295 return -EINVAL;
296
297 write_lock(&ipip6_lock);
298
299 for (p = t->prl; p; p = p->next) {
300 if (p->addr == a->addr) {
301 if (chg)
302 goto update;
303 err = -EEXIST;
304 goto out;
305 }
306 }
307
308 if (chg) {
309 err = -ENXIO;
310 goto out;
311 }
312
313 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
314 if (!p) {
315 err = -ENOBUFS;
316 goto out;
317 }
318
319 p->next = t->prl;
320 t->prl = p;
321 t->prl_count++;
322 update:
323 p->addr = a->addr;
324 p->flags = a->flags;
325 out:
326 write_unlock(&ipip6_lock);
327 return err;
328 }
329
330 static int
331 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
332 {
333 struct ip_tunnel_prl_entry *x, **p;
334 int err = 0;
335
336 write_lock(&ipip6_lock);
337
338 if (a && a->addr != htonl(INADDR_ANY)) {
339 for (p = &t->prl; *p; p = &(*p)->next) {
340 if ((*p)->addr == a->addr) {
341 x = *p;
342 *p = x->next;
343 kfree(x);
344 t->prl_count--;
345 goto out;
346 }
347 }
348 err = -ENXIO;
349 } else {
350 while (t->prl) {
351 x = t->prl;
352 t->prl = t->prl->next;
353 kfree(x);
354 t->prl_count--;
355 }
356 }
357 out:
358 write_unlock(&ipip6_lock);
359 return 0;
360 }
361
362 static int
363 isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
364 {
365 struct ip_tunnel_prl_entry *p;
366 int ok = 1;
367
368 read_lock(&ipip6_lock);
369 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
370 if (p) {
371 if (p->flags & PRL_DEFAULT)
372 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
373 else
374 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
375 } else {
376 struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
377 if (ipv6_addr_is_isatap(addr6) &&
378 (addr6->s6_addr32[3] == iph->saddr) &&
379 ipv6_chk_prefix(addr6, t->dev))
380 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
381 else
382 ok = 0;
383 }
384 read_unlock(&ipip6_lock);
385 return ok;
386 }
387
388 static void ipip6_tunnel_uninit(struct net_device *dev)
389 {
390 struct net *net = dev_net(dev);
391 struct sit_net *sitn = net_generic(net, sit_net_id);
392
393 if (dev == sitn->fb_tunnel_dev) {
394 write_lock_bh(&ipip6_lock);
395 sitn->tunnels_wc[0] = NULL;
396 write_unlock_bh(&ipip6_lock);
397 dev_put(dev);
398 } else {
399 ipip6_tunnel_unlink(sitn, netdev_priv(dev));
400 ipip6_tunnel_del_prl(netdev_priv(dev), NULL);
401 dev_put(dev);
402 }
403 }
404
405
406 static int ipip6_err(struct sk_buff *skb, u32 info)
407 {
408
409 /* All the routers (except for Linux) return only
410 8 bytes of packet payload. It means, that precise relaying of
411 ICMP in the real Internet is absolutely infeasible.
412 */
413 struct iphdr *iph = (struct iphdr*)skb->data;
414 const int type = icmp_hdr(skb)->type;
415 const int code = icmp_hdr(skb)->code;
416 struct ip_tunnel *t;
417 int err;
418
419 switch (type) {
420 default:
421 case ICMP_PARAMETERPROB:
422 return 0;
423
424 case ICMP_DEST_UNREACH:
425 switch (code) {
426 case ICMP_SR_FAILED:
427 case ICMP_PORT_UNREACH:
428 /* Impossible event. */
429 return 0;
430 case ICMP_FRAG_NEEDED:
431 /* Soft state for pmtu is maintained by IP core. */
432 return 0;
433 default:
434 /* All others are translated to HOST_UNREACH.
435 rfc2003 contains "deep thoughts" about NET_UNREACH,
436 I believe they are just ether pollution. --ANK
437 */
438 break;
439 }
440 break;
441 case ICMP_TIME_EXCEEDED:
442 if (code != ICMP_EXC_TTL)
443 return 0;
444 break;
445 }
446
447 err = -ENOENT;
448
449 read_lock(&ipip6_lock);
450 t = ipip6_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
451 if (t == NULL || t->parms.iph.daddr == 0)
452 goto out;
453
454 err = 0;
455 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
456 goto out;
457
458 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
459 t->err_count++;
460 else
461 t->err_count = 1;
462 t->err_time = jiffies;
463 out:
464 read_unlock(&ipip6_lock);
465 return err;
466 }
467
468 static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
469 {
470 if (INET_ECN_is_ce(iph->tos))
471 IP6_ECN_set_ce(ipv6_hdr(skb));
472 }
473
474 static int ipip6_rcv(struct sk_buff *skb)
475 {
476 struct iphdr *iph;
477 struct ip_tunnel *tunnel;
478
479 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
480 goto out;
481
482 iph = ip_hdr(skb);
483
484 read_lock(&ipip6_lock);
485 if ((tunnel = ipip6_tunnel_lookup(dev_net(skb->dev),
486 iph->saddr, iph->daddr)) != NULL) {
487 secpath_reset(skb);
488 skb->mac_header = skb->network_header;
489 skb_reset_network_header(skb);
490 IPCB(skb)->flags = 0;
491 skb->protocol = htons(ETH_P_IPV6);
492 skb->pkt_type = PACKET_HOST;
493
494 if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
495 !isatap_chksrc(skb, iph, tunnel)) {
496 tunnel->stat.rx_errors++;
497 read_unlock(&ipip6_lock);
498 kfree_skb(skb);
499 return 0;
500 }
501 tunnel->stat.rx_packets++;
502 tunnel->stat.rx_bytes += skb->len;
503 skb->dev = tunnel->dev;
504 dst_release(skb->dst);
505 skb->dst = NULL;
506 nf_reset(skb);
507 ipip6_ecn_decapsulate(iph, skb);
508 netif_rx(skb);
509 read_unlock(&ipip6_lock);
510 return 0;
511 }
512
513 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
514 read_unlock(&ipip6_lock);
515 out:
516 kfree_skb(skb);
517 return 0;
518 }
519
520 /* Returns the embedded IPv4 address if the IPv6 address
521 comes from 6to4 (RFC 3056) addr space */
522
523 static inline __be32 try_6to4(struct in6_addr *v6dst)
524 {
525 __be32 dst = 0;
526
527 if (v6dst->s6_addr16[0] == htons(0x2002)) {
528 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
529 memcpy(&dst, &v6dst->s6_addr16[1], 4);
530 }
531 return dst;
532 }
533
534 /*
535 * This function assumes it is being called from dev_queue_xmit()
536 * and that skb is filled properly by that function.
537 */
538
539 static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
540 {
541 struct ip_tunnel *tunnel = netdev_priv(dev);
542 struct net_device_stats *stats = &tunnel->stat;
543 struct iphdr *tiph = &tunnel->parms.iph;
544 struct ipv6hdr *iph6 = ipv6_hdr(skb);
545 u8 tos = tunnel->parms.iph.tos;
546 struct rtable *rt; /* Route to the other host */
547 struct net_device *tdev; /* Device to other host */
548 struct iphdr *iph; /* Our new IP header */
549 unsigned int max_headroom; /* The extra header space needed */
550 __be32 dst = tiph->daddr;
551 int mtu;
552 struct in6_addr *addr6;
553 int addr_type;
554
555 if (tunnel->recursion++) {
556 tunnel->stat.collisions++;
557 goto tx_error;
558 }
559
560 if (skb->protocol != htons(ETH_P_IPV6))
561 goto tx_error;
562
563 /* ISATAP (RFC4214) - must come before 6to4 */
564 if (dev->priv_flags & IFF_ISATAP) {
565 struct neighbour *neigh = NULL;
566
567 if (skb->dst)
568 neigh = skb->dst->neighbour;
569
570 if (neigh == NULL) {
571 if (net_ratelimit())
572 printk(KERN_DEBUG "sit: nexthop == NULL\n");
573 goto tx_error;
574 }
575
576 addr6 = (struct in6_addr*)&neigh->primary_key;
577 addr_type = ipv6_addr_type(addr6);
578
579 if ((addr_type & IPV6_ADDR_UNICAST) &&
580 ipv6_addr_is_isatap(addr6))
581 dst = addr6->s6_addr32[3];
582 else
583 goto tx_error;
584 }
585
586 if (!dst)
587 dst = try_6to4(&iph6->daddr);
588
589 if (!dst) {
590 struct neighbour *neigh = NULL;
591
592 if (skb->dst)
593 neigh = skb->dst->neighbour;
594
595 if (neigh == NULL) {
596 if (net_ratelimit())
597 printk(KERN_DEBUG "sit: nexthop == NULL\n");
598 goto tx_error;
599 }
600
601 addr6 = (struct in6_addr*)&neigh->primary_key;
602 addr_type = ipv6_addr_type(addr6);
603
604 if (addr_type == IPV6_ADDR_ANY) {
605 addr6 = &ipv6_hdr(skb)->daddr;
606 addr_type = ipv6_addr_type(addr6);
607 }
608
609 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
610 goto tx_error_icmp;
611
612 dst = addr6->s6_addr32[3];
613 }
614
615 {
616 struct flowi fl = { .nl_u = { .ip4_u =
617 { .daddr = dst,
618 .saddr = tiph->saddr,
619 .tos = RT_TOS(tos) } },
620 .oif = tunnel->parms.link,
621 .proto = IPPROTO_IPV6 };
622 if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
623 tunnel->stat.tx_carrier_errors++;
624 goto tx_error_icmp;
625 }
626 }
627 if (rt->rt_type != RTN_UNICAST) {
628 ip_rt_put(rt);
629 tunnel->stat.tx_carrier_errors++;
630 goto tx_error_icmp;
631 }
632 tdev = rt->u.dst.dev;
633
634 if (tdev == dev) {
635 ip_rt_put(rt);
636 tunnel->stat.collisions++;
637 goto tx_error;
638 }
639
640 if (tiph->frag_off)
641 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
642 else
643 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
644
645 if (mtu < 68) {
646 tunnel->stat.collisions++;
647 ip_rt_put(rt);
648 goto tx_error;
649 }
650 if (mtu < IPV6_MIN_MTU)
651 mtu = IPV6_MIN_MTU;
652 if (tunnel->parms.iph.daddr && skb->dst)
653 skb->dst->ops->update_pmtu(skb->dst, mtu);
654
655 if (skb->len > mtu) {
656 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
657 ip_rt_put(rt);
658 goto tx_error;
659 }
660
661 if (tunnel->err_count > 0) {
662 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
663 tunnel->err_count--;
664 dst_link_failure(skb);
665 } else
666 tunnel->err_count = 0;
667 }
668
669 /*
670 * Okay, now see if we can stuff it in the buffer as-is.
671 */
672 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
673
674 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
675 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
676 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
677 if (!new_skb) {
678 ip_rt_put(rt);
679 stats->tx_dropped++;
680 dev_kfree_skb(skb);
681 tunnel->recursion--;
682 return 0;
683 }
684 if (skb->sk)
685 skb_set_owner_w(new_skb, skb->sk);
686 dev_kfree_skb(skb);
687 skb = new_skb;
688 iph6 = ipv6_hdr(skb);
689 }
690
691 skb->transport_header = skb->network_header;
692 skb_push(skb, sizeof(struct iphdr));
693 skb_reset_network_header(skb);
694 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
695 IPCB(skb)->flags = 0;
696 dst_release(skb->dst);
697 skb->dst = &rt->u.dst;
698
699 /*
700 * Push down and install the IPIP header.
701 */
702
703 iph = ip_hdr(skb);
704 iph->version = 4;
705 iph->ihl = sizeof(struct iphdr)>>2;
706 if (mtu > IPV6_MIN_MTU)
707 iph->frag_off = htons(IP_DF);
708 else
709 iph->frag_off = 0;
710
711 iph->protocol = IPPROTO_IPV6;
712 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
713 iph->daddr = rt->rt_dst;
714 iph->saddr = rt->rt_src;
715
716 if ((iph->ttl = tiph->ttl) == 0)
717 iph->ttl = iph6->hop_limit;
718
719 nf_reset(skb);
720
721 IPTUNNEL_XMIT();
722 tunnel->recursion--;
723 return 0;
724
725 tx_error_icmp:
726 dst_link_failure(skb);
727 tx_error:
728 stats->tx_errors++;
729 dev_kfree_skb(skb);
730 tunnel->recursion--;
731 return 0;
732 }
733
734 static void ipip6_tunnel_bind_dev(struct net_device *dev)
735 {
736 struct net_device *tdev = NULL;
737 struct ip_tunnel *tunnel;
738 struct iphdr *iph;
739
740 tunnel = netdev_priv(dev);
741 iph = &tunnel->parms.iph;
742
743 if (iph->daddr) {
744 struct flowi fl = { .nl_u = { .ip4_u =
745 { .daddr = iph->daddr,
746 .saddr = iph->saddr,
747 .tos = RT_TOS(iph->tos) } },
748 .oif = tunnel->parms.link,
749 .proto = IPPROTO_IPV6 };
750 struct rtable *rt;
751 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
752 tdev = rt->u.dst.dev;
753 ip_rt_put(rt);
754 }
755 dev->flags |= IFF_POINTOPOINT;
756 }
757
758 if (!tdev && tunnel->parms.link)
759 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
760
761 if (tdev) {
762 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
763 dev->mtu = tdev->mtu - sizeof(struct iphdr);
764 if (dev->mtu < IPV6_MIN_MTU)
765 dev->mtu = IPV6_MIN_MTU;
766 }
767 dev->iflink = tunnel->parms.link;
768 }
769
770 static int
771 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
772 {
773 int err = 0;
774 struct ip_tunnel_parm p;
775 struct ip_tunnel_prl prl;
776 struct ip_tunnel *t;
777 struct net *net = dev_net(dev);
778 struct sit_net *sitn = net_generic(net, sit_net_id);
779
780 switch (cmd) {
781 case SIOCGETTUNNEL:
782 t = NULL;
783 if (dev == sitn->fb_tunnel_dev) {
784 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
785 err = -EFAULT;
786 break;
787 }
788 t = ipip6_tunnel_locate(net, &p, 0);
789 }
790 if (t == NULL)
791 t = netdev_priv(dev);
792 memcpy(&p, &t->parms, sizeof(p));
793 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
794 err = -EFAULT;
795 break;
796
797 case SIOCADDTUNNEL:
798 case SIOCCHGTUNNEL:
799 err = -EPERM;
800 if (!capable(CAP_NET_ADMIN))
801 goto done;
802
803 err = -EFAULT;
804 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
805 goto done;
806
807 err = -EINVAL;
808 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
809 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
810 goto done;
811 if (p.iph.ttl)
812 p.iph.frag_off |= htons(IP_DF);
813
814 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
815
816 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
817 if (t != NULL) {
818 if (t->dev != dev) {
819 err = -EEXIST;
820 break;
821 }
822 } else {
823 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
824 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
825 err = -EINVAL;
826 break;
827 }
828 t = netdev_priv(dev);
829 ipip6_tunnel_unlink(sitn, t);
830 t->parms.iph.saddr = p.iph.saddr;
831 t->parms.iph.daddr = p.iph.daddr;
832 memcpy(dev->dev_addr, &p.iph.saddr, 4);
833 memcpy(dev->broadcast, &p.iph.daddr, 4);
834 ipip6_tunnel_link(sitn, t);
835 netdev_state_change(dev);
836 }
837 }
838
839 if (t) {
840 err = 0;
841 if (cmd == SIOCCHGTUNNEL) {
842 t->parms.iph.ttl = p.iph.ttl;
843 t->parms.iph.tos = p.iph.tos;
844 if (t->parms.link != p.link) {
845 t->parms.link = p.link;
846 ipip6_tunnel_bind_dev(dev);
847 netdev_state_change(dev);
848 }
849 }
850 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
851 err = -EFAULT;
852 } else
853 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
854 break;
855
856 case SIOCDELTUNNEL:
857 err = -EPERM;
858 if (!capable(CAP_NET_ADMIN))
859 goto done;
860
861 if (dev == sitn->fb_tunnel_dev) {
862 err = -EFAULT;
863 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
864 goto done;
865 err = -ENOENT;
866 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
867 goto done;
868 err = -EPERM;
869 if (t == netdev_priv(sitn->fb_tunnel_dev))
870 goto done;
871 dev = t->dev;
872 }
873 unregister_netdevice(dev);
874 err = 0;
875 break;
876
877 case SIOCGETPRL:
878 err = -EINVAL;
879 if (dev == sitn->fb_tunnel_dev)
880 goto done;
881 err = -ENOENT;
882 if (!(t = netdev_priv(dev)))
883 goto done;
884 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
885 break;
886
887 case SIOCADDPRL:
888 case SIOCDELPRL:
889 case SIOCCHGPRL:
890 err = -EPERM;
891 if (!capable(CAP_NET_ADMIN))
892 goto done;
893 err = -EINVAL;
894 if (dev == sitn->fb_tunnel_dev)
895 goto done;
896 err = -EFAULT;
897 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
898 goto done;
899 err = -ENOENT;
900 if (!(t = netdev_priv(dev)))
901 goto done;
902
903 switch (cmd) {
904 case SIOCDELPRL:
905 err = ipip6_tunnel_del_prl(t, &prl);
906 break;
907 case SIOCADDPRL:
908 case SIOCCHGPRL:
909 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
910 break;
911 }
912 netdev_state_change(dev);
913 break;
914
915 default:
916 err = -EINVAL;
917 }
918
919 done:
920 return err;
921 }
922
923 static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
924 {
925 return &(((struct ip_tunnel*)netdev_priv(dev))->stat);
926 }
927
928 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
929 {
930 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
931 return -EINVAL;
932 dev->mtu = new_mtu;
933 return 0;
934 }
935
936 static void ipip6_tunnel_setup(struct net_device *dev)
937 {
938 dev->uninit = ipip6_tunnel_uninit;
939 dev->destructor = free_netdev;
940 dev->hard_start_xmit = ipip6_tunnel_xmit;
941 dev->get_stats = ipip6_tunnel_get_stats;
942 dev->do_ioctl = ipip6_tunnel_ioctl;
943 dev->change_mtu = ipip6_tunnel_change_mtu;
944
945 dev->type = ARPHRD_SIT;
946 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
947 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
948 dev->flags = IFF_NOARP;
949 dev->iflink = 0;
950 dev->addr_len = 4;
951 dev->features |= NETIF_F_NETNS_LOCAL;
952 }
953
954 static int ipip6_tunnel_init(struct net_device *dev)
955 {
956 struct ip_tunnel *tunnel;
957
958 tunnel = netdev_priv(dev);
959
960 tunnel->dev = dev;
961 strcpy(tunnel->parms.name, dev->name);
962
963 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
964 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
965
966 ipip6_tunnel_bind_dev(dev);
967
968 return 0;
969 }
970
971 static int ipip6_fb_tunnel_init(struct net_device *dev)
972 {
973 struct ip_tunnel *tunnel = netdev_priv(dev);
974 struct iphdr *iph = &tunnel->parms.iph;
975 struct net *net = dev_net(dev);
976 struct sit_net *sitn = net_generic(net, sit_net_id);
977
978 tunnel->dev = dev;
979 strcpy(tunnel->parms.name, dev->name);
980
981 iph->version = 4;
982 iph->protocol = IPPROTO_IPV6;
983 iph->ihl = 5;
984 iph->ttl = 64;
985
986 dev_hold(dev);
987 sitn->tunnels_wc[0] = tunnel;
988 return 0;
989 }
990
991 static struct xfrm_tunnel sit_handler = {
992 .handler = ipip6_rcv,
993 .err_handler = ipip6_err,
994 .priority = 1,
995 };
996
997 static void sit_destroy_tunnels(struct sit_net *sitn)
998 {
999 int prio;
1000
1001 for (prio = 1; prio < 4; prio++) {
1002 int h;
1003 for (h = 0; h < HASH_SIZE; h++) {
1004 struct ip_tunnel *t;
1005 while ((t = sitn->tunnels[prio][h]) != NULL)
1006 unregister_netdevice(t->dev);
1007 }
1008 }
1009 }
1010
1011 static int sit_init_net(struct net *net)
1012 {
1013 int err;
1014 struct sit_net *sitn;
1015
1016 err = -ENOMEM;
1017 sitn = kzalloc(sizeof(struct sit_net), GFP_KERNEL);
1018 if (sitn == NULL)
1019 goto err_alloc;
1020
1021 err = net_assign_generic(net, sit_net_id, sitn);
1022 if (err < 0)
1023 goto err_assign;
1024
1025 sitn->tunnels[0] = sitn->tunnels_wc;
1026 sitn->tunnels[1] = sitn->tunnels_l;
1027 sitn->tunnels[2] = sitn->tunnels_r;
1028 sitn->tunnels[3] = sitn->tunnels_r_l;
1029
1030 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1031 ipip6_tunnel_setup);
1032 if (!sitn->fb_tunnel_dev) {
1033 err = -ENOMEM;
1034 goto err_alloc_dev;
1035 }
1036
1037 sitn->fb_tunnel_dev->init = ipip6_fb_tunnel_init;
1038 dev_net_set(sitn->fb_tunnel_dev, net);
1039
1040 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1041 goto err_reg_dev;
1042
1043 return 0;
1044
1045 err_reg_dev:
1046 free_netdev(sitn->fb_tunnel_dev);
1047 err_alloc_dev:
1048 /* nothing */
1049 err_assign:
1050 kfree(sitn);
1051 err_alloc:
1052 return err;
1053 }
1054
1055 static void sit_exit_net(struct net *net)
1056 {
1057 struct sit_net *sitn;
1058
1059 sitn = net_generic(net, sit_net_id);
1060 rtnl_lock();
1061 sit_destroy_tunnels(sitn);
1062 unregister_netdevice(sitn->fb_tunnel_dev);
1063 rtnl_unlock();
1064 kfree(sitn);
1065 }
1066
1067 static struct pernet_operations sit_net_ops = {
1068 .init = sit_init_net,
1069 .exit = sit_exit_net,
1070 };
1071
1072 static void __exit sit_cleanup(void)
1073 {
1074 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1075
1076 unregister_pernet_gen_device(sit_net_id, &sit_net_ops);
1077 }
1078
1079 static int __init sit_init(void)
1080 {
1081 int err;
1082
1083 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
1084
1085 if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) {
1086 printk(KERN_INFO "sit init: Can't add protocol\n");
1087 return -EAGAIN;
1088 }
1089
1090 err = register_pernet_gen_device(&sit_net_id, &sit_net_ops);
1091 if (err < 0)
1092 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1093
1094 return err;
1095 }
1096
1097 module_init(sit_init);
1098 module_exit(sit_cleanup);
1099 MODULE_LICENSE("GPL");
1100 MODULE_ALIAS("sit0");