?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
netfilter: nf_conntrack: add support for "conntrack zones"
[linux/fpc-iii.git] / net / ipv6 / sit.c
blob10207cc8cc0e2d4da01f2e7d069d01988a38997a
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 <asm/uaccess.h>
32 #include <linux/init.h>
33 #include <linux/netfilter_ipv4.h>
34 #include <linux/if_ether.h>
35
36 #include <net/sock.h>
37 #include <net/snmp.h>
38
39 #include <net/ipv6.h>
40 #include <net/protocol.h>
41 #include <net/transp_v6.h>
42 #include <net/ip6_fib.h>
43 #include <net/ip6_route.h>
44 #include <net/ndisc.h>
45 #include <net/addrconf.h>
46 #include <net/ip.h>
47 #include <net/udp.h>
48 #include <net/icmp.h>
49 #include <net/ipip.h>
50 #include <net/inet_ecn.h>
51 #include <net/xfrm.h>
52 #include <net/dsfield.h>
53 #include <net/net_namespace.h>
54 #include <net/netns/generic.h>
55
56 /*
57 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
58
59 For comments look at net/ipv4/ip_gre.c --ANK
60 */
61
62 #define HASH_SIZE 16
63 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
64
65 static void ipip6_tunnel_init(struct net_device *dev);
66 static void ipip6_tunnel_setup(struct net_device *dev);
67
68 static int sit_net_id __read_mostly;
69 struct sit_net {
70 struct ip_tunnel *tunnels_r_l[HASH_SIZE];
71 struct ip_tunnel *tunnels_r[HASH_SIZE];
72 struct ip_tunnel *tunnels_l[HASH_SIZE];
73 struct ip_tunnel *tunnels_wc[1];
74 struct ip_tunnel **tunnels[4];
75
76 struct net_device *fb_tunnel_dev;
77 };
78
79 /*
80 * Locking : hash tables are protected by RCU and a spinlock
81 */
82 static DEFINE_SPINLOCK(ipip6_lock);
83
84 #define for_each_ip_tunnel_rcu(start) \
85 for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
86
87 /*
88 * Must be invoked with rcu_read_lock
89 */
90 static struct ip_tunnel * ipip6_tunnel_lookup(struct net *net,
91 struct net_device *dev, __be32 remote, __be32 local)
92 {
93 unsigned h0 = HASH(remote);
94 unsigned h1 = HASH(local);
95 struct ip_tunnel *t;
96 struct sit_net *sitn = net_generic(net, sit_net_id);
97
98 for_each_ip_tunnel_rcu(sitn->tunnels_r_l[h0 ^ h1]) {
99 if (local == t->parms.iph.saddr &&
100 remote == t->parms.iph.daddr &&
101 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
102 (t->dev->flags & IFF_UP))
103 return t;
104 }
105 for_each_ip_tunnel_rcu(sitn->tunnels_r[h0]) {
106 if (remote == t->parms.iph.daddr &&
107 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
108 (t->dev->flags & IFF_UP))
109 return t;
110 }
111 for_each_ip_tunnel_rcu(sitn->tunnels_l[h1]) {
112 if (local == t->parms.iph.saddr &&
113 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
114 (t->dev->flags & IFF_UP))
115 return t;
116 }
117 t = rcu_dereference(sitn->tunnels_wc[0]);
118 if ((t != NULL) && (t->dev->flags & IFF_UP))
119 return t;
120 return NULL;
121 }
122
123 static struct ip_tunnel **__ipip6_bucket(struct sit_net *sitn,
124 struct ip_tunnel_parm *parms)
125 {
126 __be32 remote = parms->iph.daddr;
127 __be32 local = parms->iph.saddr;
128 unsigned h = 0;
129 int prio = 0;
130
131 if (remote) {
132 prio |= 2;
133 h ^= HASH(remote);
134 }
135 if (local) {
136 prio |= 1;
137 h ^= HASH(local);
138 }
139 return &sitn->tunnels[prio][h];
140 }
141
142 static inline struct ip_tunnel **ipip6_bucket(struct sit_net *sitn,
143 struct ip_tunnel *t)
144 {
145 return __ipip6_bucket(sitn, &t->parms);
146 }
147
148 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
149 {
150 struct ip_tunnel **tp;
151
152 for (tp = ipip6_bucket(sitn, t); *tp; tp = &(*tp)->next) {
153 if (t == *tp) {
154 spin_lock_bh(&ipip6_lock);
155 *tp = t->next;
156 spin_unlock_bh(&ipip6_lock);
157 break;
158 }
159 }
160 }
161
162 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
163 {
164 struct ip_tunnel **tp = ipip6_bucket(sitn, t);
165
166 spin_lock_bh(&ipip6_lock);
167 t->next = *tp;
168 rcu_assign_pointer(*tp, t);
169 spin_unlock_bh(&ipip6_lock);
170 }
171
172 static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
173 {
174 #ifdef CONFIG_IPV6_SIT_6RD
175 struct ip_tunnel *t = netdev_priv(dev);
176
177 if (t->dev == sitn->fb_tunnel_dev) {
178 ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0);
179 t->ip6rd.relay_prefix = 0;
180 t->ip6rd.prefixlen = 16;
181 t->ip6rd.relay_prefixlen = 0;
182 } else {
183 struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev);
184 memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd));
185 }
186 #endif
187 }
188
189 static struct ip_tunnel * ipip6_tunnel_locate(struct net *net,
190 struct ip_tunnel_parm *parms, int create)
191 {
192 __be32 remote = parms->iph.daddr;
193 __be32 local = parms->iph.saddr;
194 struct ip_tunnel *t, **tp, *nt;
195 struct net_device *dev;
196 char name[IFNAMSIZ];
197 struct sit_net *sitn = net_generic(net, sit_net_id);
198
199 for (tp = __ipip6_bucket(sitn, parms); (t = *tp) != NULL; tp = &t->next) {
200 if (local == t->parms.iph.saddr &&
201 remote == t->parms.iph.daddr &&
202 parms->link == t->parms.link) {
203 if (create)
204 return NULL;
205 else
206 return t;
207 }
208 }
209 if (!create)
210 goto failed;
211
212 if (parms->name[0])
213 strlcpy(name, parms->name, IFNAMSIZ);
214 else
215 sprintf(name, "sit%%d");
216
217 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
218 if (dev == NULL)
219 return NULL;
220
221 dev_net_set(dev, net);
222
223 if (strchr(name, '%')) {
224 if (dev_alloc_name(dev, name) < 0)
225 goto failed_free;
226 }
227
228 nt = netdev_priv(dev);
229
230 nt->parms = *parms;
231 ipip6_tunnel_init(dev);
232 ipip6_tunnel_clone_6rd(dev, sitn);
233
234 if (parms->i_flags & SIT_ISATAP)
235 dev->priv_flags |= IFF_ISATAP;
236
237 if (register_netdevice(dev) < 0)
238 goto failed_free;
239
240 dev_hold(dev);
241
242 ipip6_tunnel_link(sitn, nt);
243 return nt;
244
245 failed_free:
246 free_netdev(dev);
247 failed:
248 return NULL;
249 }
250
251 static DEFINE_SPINLOCK(ipip6_prl_lock);
252
253 #define for_each_prl_rcu(start) \
254 for (prl = rcu_dereference(start); \
255 prl; \
256 prl = rcu_dereference(prl->next))
257
258 static struct ip_tunnel_prl_entry *
259 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
260 {
261 struct ip_tunnel_prl_entry *prl;
262
263 for_each_prl_rcu(t->prl)
264 if (prl->addr == addr)
265 break;
266 return prl;
267
268 }
269
270 static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
271 struct ip_tunnel_prl __user *a)
272 {
273 struct ip_tunnel_prl kprl, *kp;
274 struct ip_tunnel_prl_entry *prl;
275 unsigned int cmax, c = 0, ca, len;
276 int ret = 0;
277
278 if (copy_from_user(&kprl, a, sizeof(kprl)))
279 return -EFAULT;
280 cmax = kprl.datalen / sizeof(kprl);
281 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
282 cmax = 1;
283
284 /* For simple GET or for root users,
285 * we try harder to allocate.
286 */
287 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
288 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
289 NULL;
290
291 rcu_read_lock();
292
293 ca = t->prl_count < cmax ? t->prl_count : cmax;
294
295 if (!kp) {
296 /* We don't try hard to allocate much memory for
297 * non-root users.
298 * For root users, retry allocating enough memory for
299 * the answer.
300 */
301 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
302 if (!kp) {
303 ret = -ENOMEM;
304 goto out;
305 }
306 }
307
308 c = 0;
309 for_each_prl_rcu(t->prl) {
310 if (c >= cmax)
311 break;
312 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
313 continue;
314 kp[c].addr = prl->addr;
315 kp[c].flags = prl->flags;
316 c++;
317 if (kprl.addr != htonl(INADDR_ANY))
318 break;
319 }
320 out:
321 rcu_read_unlock();
322
323 len = sizeof(*kp) * c;
324 ret = 0;
325 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
326 ret = -EFAULT;
327
328 kfree(kp);
329
330 return ret;
331 }
332
333 static int
334 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
335 {
336 struct ip_tunnel_prl_entry *p;
337 int err = 0;
338
339 if (a->addr == htonl(INADDR_ANY))
340 return -EINVAL;
341
342 spin_lock(&ipip6_prl_lock);
343
344 for (p = t->prl; p; p = p->next) {
345 if (p->addr == a->addr) {
346 if (chg) {
347 p->flags = a->flags;
348 goto out;
349 }
350 err = -EEXIST;
351 goto out;
352 }
353 }
354
355 if (chg) {
356 err = -ENXIO;
357 goto out;
358 }
359
360 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
361 if (!p) {
362 err = -ENOBUFS;
363 goto out;
364 }
365
366 INIT_RCU_HEAD(&p->rcu_head);
367 p->next = t->prl;
368 p->addr = a->addr;
369 p->flags = a->flags;
370 t->prl_count++;
371 rcu_assign_pointer(t->prl, p);
372 out:
373 spin_unlock(&ipip6_prl_lock);
374 return err;
375 }
376
377 static void prl_entry_destroy_rcu(struct rcu_head *head)
378 {
379 kfree(container_of(head, struct ip_tunnel_prl_entry, rcu_head));
380 }
381
382 static void prl_list_destroy_rcu(struct rcu_head *head)
383 {
384 struct ip_tunnel_prl_entry *p, *n;
385
386 p = container_of(head, struct ip_tunnel_prl_entry, rcu_head);
387 do {
388 n = p->next;
389 kfree(p);
390 p = n;
391 } while (p);
392 }
393
394 static int
395 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
396 {
397 struct ip_tunnel_prl_entry *x, **p;
398 int err = 0;
399
400 spin_lock(&ipip6_prl_lock);
401
402 if (a && a->addr != htonl(INADDR_ANY)) {
403 for (p = &t->prl; *p; p = &(*p)->next) {
404 if ((*p)->addr == a->addr) {
405 x = *p;
406 *p = x->next;
407 call_rcu(&x->rcu_head, prl_entry_destroy_rcu);
408 t->prl_count--;
409 goto out;
410 }
411 }
412 err = -ENXIO;
413 } else {
414 if (t->prl) {
415 t->prl_count = 0;
416 x = t->prl;
417 call_rcu(&x->rcu_head, prl_list_destroy_rcu);
418 t->prl = NULL;
419 }
420 }
421 out:
422 spin_unlock(&ipip6_prl_lock);
423 return err;
424 }
425
426 static int
427 isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
428 {
429 struct ip_tunnel_prl_entry *p;
430 int ok = 1;
431
432 rcu_read_lock();
433 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
434 if (p) {
435 if (p->flags & PRL_DEFAULT)
436 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
437 else
438 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
439 } else {
440 struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
441 if (ipv6_addr_is_isatap(addr6) &&
442 (addr6->s6_addr32[3] == iph->saddr) &&
443 ipv6_chk_prefix(addr6, t->dev))
444 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
445 else
446 ok = 0;
447 }
448 rcu_read_unlock();
449 return ok;
450 }
451
452 static void ipip6_tunnel_uninit(struct net_device *dev)
453 {
454 struct net *net = dev_net(dev);
455 struct sit_net *sitn = net_generic(net, sit_net_id);
456
457 if (dev == sitn->fb_tunnel_dev) {
458 spin_lock_bh(&ipip6_lock);
459 sitn->tunnels_wc[0] = NULL;
460 spin_unlock_bh(&ipip6_lock);
461 dev_put(dev);
462 } else {
463 ipip6_tunnel_unlink(sitn, netdev_priv(dev));
464 ipip6_tunnel_del_prl(netdev_priv(dev), NULL);
465 dev_put(dev);
466 }
467 }
468
469
470 static int ipip6_err(struct sk_buff *skb, u32 info)
471 {
472
473 /* All the routers (except for Linux) return only
474 8 bytes of packet payload. It means, that precise relaying of
475 ICMP in the real Internet is absolutely infeasible.
476 */
477 struct iphdr *iph = (struct iphdr*)skb->data;
478 const int type = icmp_hdr(skb)->type;
479 const int code = icmp_hdr(skb)->code;
480 struct ip_tunnel *t;
481 int err;
482
483 switch (type) {
484 default:
485 case ICMP_PARAMETERPROB:
486 return 0;
487
488 case ICMP_DEST_UNREACH:
489 switch (code) {
490 case ICMP_SR_FAILED:
491 case ICMP_PORT_UNREACH:
492 /* Impossible event. */
493 return 0;
494 case ICMP_FRAG_NEEDED:
495 /* Soft state for pmtu is maintained by IP core. */
496 return 0;
497 default:
498 /* All others are translated to HOST_UNREACH.
499 rfc2003 contains "deep thoughts" about NET_UNREACH,
500 I believe they are just ether pollution. --ANK
501 */
502 break;
503 }
504 break;
505 case ICMP_TIME_EXCEEDED:
506 if (code != ICMP_EXC_TTL)
507 return 0;
508 break;
509 }
510
511 err = -ENOENT;
512
513 rcu_read_lock();
514 t = ipip6_tunnel_lookup(dev_net(skb->dev),
515 skb->dev,
516 iph->daddr,
517 iph->saddr);
518 if (t == NULL || t->parms.iph.daddr == 0)
519 goto out;
520
521 err = 0;
522 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
523 goto out;
524
525 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
526 t->err_count++;
527 else
528 t->err_count = 1;
529 t->err_time = jiffies;
530 out:
531 rcu_read_unlock();
532 return err;
533 }
534
535 static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
536 {
537 if (INET_ECN_is_ce(iph->tos))
538 IP6_ECN_set_ce(ipv6_hdr(skb));
539 }
540
541 static int ipip6_rcv(struct sk_buff *skb)
542 {
543 struct iphdr *iph;
544 struct ip_tunnel *tunnel;
545
546 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
547 goto out;
548
549 iph = ip_hdr(skb);
550
551 rcu_read_lock();
552 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
553 iph->saddr, iph->daddr);
554 if (tunnel != NULL) {
555 secpath_reset(skb);
556 skb->mac_header = skb->network_header;
557 skb_reset_network_header(skb);
558 IPCB(skb)->flags = 0;
559 skb->protocol = htons(ETH_P_IPV6);
560 skb->pkt_type = PACKET_HOST;
561
562 if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
563 !isatap_chksrc(skb, iph, tunnel)) {
564 tunnel->dev->stats.rx_errors++;
565 rcu_read_unlock();
566 kfree_skb(skb);
567 return 0;
568 }
569 tunnel->dev->stats.rx_packets++;
570 tunnel->dev->stats.rx_bytes += skb->len;
571 skb->dev = tunnel->dev;
572 skb_dst_drop(skb);
573 nf_reset(skb);
574 ipip6_ecn_decapsulate(iph, skb);
575 netif_rx(skb);
576 rcu_read_unlock();
577 return 0;
578 }
579
580 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
581 rcu_read_unlock();
582 out:
583 kfree_skb(skb);
584 return 0;
585 }
586
587 /*
588 * Returns the embedded IPv4 address if the IPv6 address
589 * comes from 6rd / 6to4 (RFC 3056) addr space.
590 */
591 static inline
592 __be32 try_6rd(struct in6_addr *v6dst, struct ip_tunnel *tunnel)
593 {
594 __be32 dst = 0;
595
596 #ifdef CONFIG_IPV6_SIT_6RD
597 if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
598 tunnel->ip6rd.prefixlen)) {
599 unsigned pbw0, pbi0;
600 int pbi1;
601 u32 d;
602
603 pbw0 = tunnel->ip6rd.prefixlen >> 5;
604 pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
605
606 d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
607 tunnel->ip6rd.relay_prefixlen;
608
609 pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
610 if (pbi1 > 0)
611 d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
612 (32 - pbi1);
613
614 dst = tunnel->ip6rd.relay_prefix | htonl(d);
615 }
616 #else
617 if (v6dst->s6_addr16[0] == htons(0x2002)) {
618 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
619 memcpy(&dst, &v6dst->s6_addr16[1], 4);
620 }
621 #endif
622 return dst;
623 }
624
625 /*
626 * This function assumes it is being called from dev_queue_xmit()
627 * and that skb is filled properly by that function.
628 */
629
630 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
631 struct net_device *dev)
632 {
633 struct ip_tunnel *tunnel = netdev_priv(dev);
634 struct net_device_stats *stats = &dev->stats;
635 struct netdev_queue *txq = netdev_get_tx_queue(dev, 0);
636 struct iphdr *tiph = &tunnel->parms.iph;
637 struct ipv6hdr *iph6 = ipv6_hdr(skb);
638 u8 tos = tunnel->parms.iph.tos;
639 __be16 df = tiph->frag_off;
640 struct rtable *rt; /* Route to the other host */
641 struct net_device *tdev; /* Device to other host */
642 struct iphdr *iph; /* Our new IP header */
643 unsigned int max_headroom; /* The extra header space needed */
644 __be32 dst = tiph->daddr;
645 int mtu;
646 struct in6_addr *addr6;
647 int addr_type;
648
649 if (skb->protocol != htons(ETH_P_IPV6))
650 goto tx_error;
651
652 /* ISATAP (RFC4214) - must come before 6to4 */
653 if (dev->priv_flags & IFF_ISATAP) {
654 struct neighbour *neigh = NULL;
655
656 if (skb_dst(skb))
657 neigh = skb_dst(skb)->neighbour;
658
659 if (neigh == NULL) {
660 if (net_ratelimit())
661 printk(KERN_DEBUG "sit: nexthop == NULL\n");
662 goto tx_error;
663 }
664
665 addr6 = (struct in6_addr*)&neigh->primary_key;
666 addr_type = ipv6_addr_type(addr6);
667
668 if ((addr_type & IPV6_ADDR_UNICAST) &&
669 ipv6_addr_is_isatap(addr6))
670 dst = addr6->s6_addr32[3];
671 else
672 goto tx_error;
673 }
674
675 if (!dst)
676 dst = try_6rd(&iph6->daddr, tunnel);
677
678 if (!dst) {
679 struct neighbour *neigh = NULL;
680
681 if (skb_dst(skb))
682 neigh = skb_dst(skb)->neighbour;
683
684 if (neigh == NULL) {
685 if (net_ratelimit())
686 printk(KERN_DEBUG "sit: nexthop == NULL\n");
687 goto tx_error;
688 }
689
690 addr6 = (struct in6_addr*)&neigh->primary_key;
691 addr_type = ipv6_addr_type(addr6);
692
693 if (addr_type == IPV6_ADDR_ANY) {
694 addr6 = &ipv6_hdr(skb)->daddr;
695 addr_type = ipv6_addr_type(addr6);
696 }
697
698 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
699 goto tx_error_icmp;
700
701 dst = addr6->s6_addr32[3];
702 }
703
704 {
705 struct flowi fl = { .nl_u = { .ip4_u =
706 { .daddr = dst,
707 .saddr = tiph->saddr,
708 .tos = RT_TOS(tos) } },
709 .oif = tunnel->parms.link,
710 .proto = IPPROTO_IPV6 };
711 if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
712 stats->tx_carrier_errors++;
713 goto tx_error_icmp;
714 }
715 }
716 if (rt->rt_type != RTN_UNICAST) {
717 ip_rt_put(rt);
718 stats->tx_carrier_errors++;
719 goto tx_error_icmp;
720 }
721 tdev = rt->u.dst.dev;
722
723 if (tdev == dev) {
724 ip_rt_put(rt);
725 stats->collisions++;
726 goto tx_error;
727 }
728
729 if (df) {
730 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
731
732 if (mtu < 68) {
733 stats->collisions++;
734 ip_rt_put(rt);
735 goto tx_error;
736 }
737
738 if (mtu < IPV6_MIN_MTU) {
739 mtu = IPV6_MIN_MTU;
740 df = 0;
741 }
742
743 if (tunnel->parms.iph.daddr && skb_dst(skb))
744 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
745
746 if (skb->len > mtu) {
747 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
748 ip_rt_put(rt);
749 goto tx_error;
750 }
751 }
752
753 if (tunnel->err_count > 0) {
754 if (time_before(jiffies,
755 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
756 tunnel->err_count--;
757 dst_link_failure(skb);
758 } else
759 tunnel->err_count = 0;
760 }
761
762 /*
763 * Okay, now see if we can stuff it in the buffer as-is.
764 */
765 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
766
767 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
768 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
769 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
770 if (!new_skb) {
771 ip_rt_put(rt);
772 txq->tx_dropped++;
773 dev_kfree_skb(skb);
774 return NETDEV_TX_OK;
775 }
776 if (skb->sk)
777 skb_set_owner_w(new_skb, skb->sk);
778 dev_kfree_skb(skb);
779 skb = new_skb;
780 iph6 = ipv6_hdr(skb);
781 }
782
783 skb->transport_header = skb->network_header;
784 skb_push(skb, sizeof(struct iphdr));
785 skb_reset_network_header(skb);
786 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
787 IPCB(skb)->flags = 0;
788 skb_dst_drop(skb);
789 skb_dst_set(skb, &rt->u.dst);
790
791 /*
792 * Push down and install the IPIP header.
793 */
794
795 iph = ip_hdr(skb);
796 iph->version = 4;
797 iph->ihl = sizeof(struct iphdr)>>2;
798 iph->frag_off = df;
799 iph->protocol = IPPROTO_IPV6;
800 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
801 iph->daddr = rt->rt_dst;
802 iph->saddr = rt->rt_src;
803
804 if ((iph->ttl = tiph->ttl) == 0)
805 iph->ttl = iph6->hop_limit;
806
807 nf_reset(skb);
808
809 IPTUNNEL_XMIT();
810 return NETDEV_TX_OK;
811
812 tx_error_icmp:
813 dst_link_failure(skb);
814 tx_error:
815 stats->tx_errors++;
816 dev_kfree_skb(skb);
817 return NETDEV_TX_OK;
818 }
819
820 static void ipip6_tunnel_bind_dev(struct net_device *dev)
821 {
822 struct net_device *tdev = NULL;
823 struct ip_tunnel *tunnel;
824 struct iphdr *iph;
825
826 tunnel = netdev_priv(dev);
827 iph = &tunnel->parms.iph;
828
829 if (iph->daddr) {
830 struct flowi fl = { .nl_u = { .ip4_u =
831 { .daddr = iph->daddr,
832 .saddr = iph->saddr,
833 .tos = RT_TOS(iph->tos) } },
834 .oif = tunnel->parms.link,
835 .proto = IPPROTO_IPV6 };
836 struct rtable *rt;
837 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
838 tdev = rt->u.dst.dev;
839 ip_rt_put(rt);
840 }
841 dev->flags |= IFF_POINTOPOINT;
842 }
843
844 if (!tdev && tunnel->parms.link)
845 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
846
847 if (tdev) {
848 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
849 dev->mtu = tdev->mtu - sizeof(struct iphdr);
850 if (dev->mtu < IPV6_MIN_MTU)
851 dev->mtu = IPV6_MIN_MTU;
852 }
853 dev->iflink = tunnel->parms.link;
854 }
855
856 static int
857 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
858 {
859 int err = 0;
860 struct ip_tunnel_parm p;
861 struct ip_tunnel_prl prl;
862 struct ip_tunnel *t;
863 struct net *net = dev_net(dev);
864 struct sit_net *sitn = net_generic(net, sit_net_id);
865 #ifdef CONFIG_IPV6_SIT_6RD
866 struct ip_tunnel_6rd ip6rd;
867 #endif
868
869 switch (cmd) {
870 case SIOCGETTUNNEL:
871 #ifdef CONFIG_IPV6_SIT_6RD
872 case SIOCGET6RD:
873 #endif
874 t = NULL;
875 if (dev == sitn->fb_tunnel_dev) {
876 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
877 err = -EFAULT;
878 break;
879 }
880 t = ipip6_tunnel_locate(net, &p, 0);
881 }
882 if (t == NULL)
883 t = netdev_priv(dev);
884
885 err = -EFAULT;
886 if (cmd == SIOCGETTUNNEL) {
887 memcpy(&p, &t->parms, sizeof(p));
888 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
889 sizeof(p)))
890 goto done;
891 #ifdef CONFIG_IPV6_SIT_6RD
892 } else {
893 ipv6_addr_copy(&ip6rd.prefix, &t->ip6rd.prefix);
894 ip6rd.relay_prefix = t->ip6rd.relay_prefix;
895 ip6rd.prefixlen = t->ip6rd.prefixlen;
896 ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
897 if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
898 sizeof(ip6rd)))
899 goto done;
900 #endif
901 }
902 err = 0;
903 break;
904
905 case SIOCADDTUNNEL:
906 case SIOCCHGTUNNEL:
907 err = -EPERM;
908 if (!capable(CAP_NET_ADMIN))
909 goto done;
910
911 err = -EFAULT;
912 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
913 goto done;
914
915 err = -EINVAL;
916 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
917 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
918 goto done;
919 if (p.iph.ttl)
920 p.iph.frag_off |= htons(IP_DF);
921
922 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
923
924 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
925 if (t != NULL) {
926 if (t->dev != dev) {
927 err = -EEXIST;
928 break;
929 }
930 } else {
931 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
932 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
933 err = -EINVAL;
934 break;
935 }
936 t = netdev_priv(dev);
937 ipip6_tunnel_unlink(sitn, t);
938 t->parms.iph.saddr = p.iph.saddr;
939 t->parms.iph.daddr = p.iph.daddr;
940 memcpy(dev->dev_addr, &p.iph.saddr, 4);
941 memcpy(dev->broadcast, &p.iph.daddr, 4);
942 ipip6_tunnel_link(sitn, t);
943 netdev_state_change(dev);
944 }
945 }
946
947 if (t) {
948 err = 0;
949 if (cmd == SIOCCHGTUNNEL) {
950 t->parms.iph.ttl = p.iph.ttl;
951 t->parms.iph.tos = p.iph.tos;
952 if (t->parms.link != p.link) {
953 t->parms.link = p.link;
954 ipip6_tunnel_bind_dev(dev);
955 netdev_state_change(dev);
956 }
957 }
958 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
959 err = -EFAULT;
960 } else
961 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
962 break;
963
964 case SIOCDELTUNNEL:
965 err = -EPERM;
966 if (!capable(CAP_NET_ADMIN))
967 goto done;
968
969 if (dev == sitn->fb_tunnel_dev) {
970 err = -EFAULT;
971 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
972 goto done;
973 err = -ENOENT;
974 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
975 goto done;
976 err = -EPERM;
977 if (t == netdev_priv(sitn->fb_tunnel_dev))
978 goto done;
979 dev = t->dev;
980 }
981 unregister_netdevice(dev);
982 err = 0;
983 break;
984
985 case SIOCGETPRL:
986 err = -EINVAL;
987 if (dev == sitn->fb_tunnel_dev)
988 goto done;
989 err = -ENOENT;
990 if (!(t = netdev_priv(dev)))
991 goto done;
992 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
993 break;
994
995 case SIOCADDPRL:
996 case SIOCDELPRL:
997 case SIOCCHGPRL:
998 err = -EPERM;
999 if (!capable(CAP_NET_ADMIN))
1000 goto done;
1001 err = -EINVAL;
1002 if (dev == sitn->fb_tunnel_dev)
1003 goto done;
1004 err = -EFAULT;
1005 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
1006 goto done;
1007 err = -ENOENT;
1008 if (!(t = netdev_priv(dev)))
1009 goto done;
1010
1011 switch (cmd) {
1012 case SIOCDELPRL:
1013 err = ipip6_tunnel_del_prl(t, &prl);
1014 break;
1015 case SIOCADDPRL:
1016 case SIOCCHGPRL:
1017 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
1018 break;
1019 }
1020 netdev_state_change(dev);
1021 break;
1022
1023 #ifdef CONFIG_IPV6_SIT_6RD
1024 case SIOCADD6RD:
1025 case SIOCCHG6RD:
1026 case SIOCDEL6RD:
1027 err = -EPERM;
1028 if (!capable(CAP_NET_ADMIN))
1029 goto done;
1030
1031 err = -EFAULT;
1032 if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
1033 sizeof(ip6rd)))
1034 goto done;
1035
1036 t = netdev_priv(dev);
1037
1038 if (cmd != SIOCDEL6RD) {
1039 struct in6_addr prefix;
1040 __be32 relay_prefix;
1041
1042 err = -EINVAL;
1043 if (ip6rd.relay_prefixlen > 32 ||
1044 ip6rd.prefixlen + (32 - ip6rd.relay_prefixlen) > 64)
1045 goto done;
1046
1047 ipv6_addr_prefix(&prefix, &ip6rd.prefix,
1048 ip6rd.prefixlen);
1049 if (!ipv6_addr_equal(&prefix, &ip6rd.prefix))
1050 goto done;
1051 if (ip6rd.relay_prefixlen)
1052 relay_prefix = ip6rd.relay_prefix &
1053 htonl(0xffffffffUL <<
1054 (32 - ip6rd.relay_prefixlen));
1055 else
1056 relay_prefix = 0;
1057 if (relay_prefix != ip6rd.relay_prefix)
1058 goto done;
1059
1060 ipv6_addr_copy(&t->ip6rd.prefix, &prefix);
1061 t->ip6rd.relay_prefix = relay_prefix;
1062 t->ip6rd.prefixlen = ip6rd.prefixlen;
1063 t->ip6rd.relay_prefixlen = ip6rd.relay_prefixlen;
1064 } else
1065 ipip6_tunnel_clone_6rd(dev, sitn);
1066
1067 err = 0;
1068 break;
1069 #endif
1070
1071 default:
1072 err = -EINVAL;
1073 }
1074
1075 done:
1076 return err;
1077 }
1078
1079 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
1080 {
1081 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
1082 return -EINVAL;
1083 dev->mtu = new_mtu;
1084 return 0;
1085 }
1086
1087 static const struct net_device_ops ipip6_netdev_ops = {
1088 .ndo_uninit = ipip6_tunnel_uninit,
1089 .ndo_start_xmit = ipip6_tunnel_xmit,
1090 .ndo_do_ioctl = ipip6_tunnel_ioctl,
1091 .ndo_change_mtu = ipip6_tunnel_change_mtu,
1092 };
1093
1094 static void ipip6_tunnel_setup(struct net_device *dev)
1095 {
1096 dev->netdev_ops = &ipip6_netdev_ops;
1097 dev->destructor = free_netdev;
1098
1099 dev->type = ARPHRD_SIT;
1100 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
1101 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
1102 dev->flags = IFF_NOARP;
1103 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1104 dev->iflink = 0;
1105 dev->addr_len = 4;
1106 dev->features |= NETIF_F_NETNS_LOCAL;
1107 }
1108
1109 static void ipip6_tunnel_init(struct net_device *dev)
1110 {
1111 struct ip_tunnel *tunnel = netdev_priv(dev);
1112
1113 tunnel->dev = dev;
1114 strcpy(tunnel->parms.name, dev->name);
1115
1116 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
1117 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
1118
1119 ipip6_tunnel_bind_dev(dev);
1120 }
1121
1122 static void __net_init ipip6_fb_tunnel_init(struct net_device *dev)
1123 {
1124 struct ip_tunnel *tunnel = netdev_priv(dev);
1125 struct iphdr *iph = &tunnel->parms.iph;
1126 struct net *net = dev_net(dev);
1127 struct sit_net *sitn = net_generic(net, sit_net_id);
1128
1129 tunnel->dev = dev;
1130 strcpy(tunnel->parms.name, dev->name);
1131
1132 iph->version = 4;
1133 iph->protocol = IPPROTO_IPV6;
1134 iph->ihl = 5;
1135 iph->ttl = 64;
1136
1137 dev_hold(dev);
1138 sitn->tunnels_wc[0] = tunnel;
1139 }
1140
1141 static struct xfrm_tunnel sit_handler = {
1142 .handler = ipip6_rcv,
1143 .err_handler = ipip6_err,
1144 .priority = 1,
1145 };
1146
1147 static void __net_exit sit_destroy_tunnels(struct sit_net *sitn, struct list_head *head)
1148 {
1149 int prio;
1150
1151 for (prio = 1; prio < 4; prio++) {
1152 int h;
1153 for (h = 0; h < HASH_SIZE; h++) {
1154 struct ip_tunnel *t = sitn->tunnels[prio][h];
1155
1156 while (t != NULL) {
1157 unregister_netdevice_queue(t->dev, head);
1158 t = t->next;
1159 }
1160 }
1161 }
1162 }
1163
1164 static int __net_init sit_init_net(struct net *net)
1165 {
1166 struct sit_net *sitn = net_generic(net, sit_net_id);
1167 int err;
1168
1169 sitn->tunnels[0] = sitn->tunnels_wc;
1170 sitn->tunnels[1] = sitn->tunnels_l;
1171 sitn->tunnels[2] = sitn->tunnels_r;
1172 sitn->tunnels[3] = sitn->tunnels_r_l;
1173
1174 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1175 ipip6_tunnel_setup);
1176 if (!sitn->fb_tunnel_dev) {
1177 err = -ENOMEM;
1178 goto err_alloc_dev;
1179 }
1180 dev_net_set(sitn->fb_tunnel_dev, net);
1181
1182 ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
1183 ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
1184
1185 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1186 goto err_reg_dev;
1187
1188 return 0;
1189
1190 err_reg_dev:
1191 dev_put(sitn->fb_tunnel_dev);
1192 free_netdev(sitn->fb_tunnel_dev);
1193 err_alloc_dev:
1194 return err;
1195 }
1196
1197 static void __net_exit sit_exit_net(struct net *net)
1198 {
1199 struct sit_net *sitn = net_generic(net, sit_net_id);
1200 LIST_HEAD(list);
1201
1202 rtnl_lock();
1203 sit_destroy_tunnels(sitn, &list);
1204 unregister_netdevice_queue(sitn->fb_tunnel_dev, &list);
1205 unregister_netdevice_many(&list);
1206 rtnl_unlock();
1207 }
1208
1209 static struct pernet_operations sit_net_ops = {
1210 .init = sit_init_net,
1211 .exit = sit_exit_net,
1212 .id = &sit_net_id,
1213 .size = sizeof(struct sit_net),
1214 };
1215
1216 static void __exit sit_cleanup(void)
1217 {
1218 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1219
1220 unregister_pernet_device(&sit_net_ops);
1221 rcu_barrier(); /* Wait for completion of call_rcu()'s */
1222 }
1223
1224 static int __init sit_init(void)
1225 {
1226 int err;
1227
1228 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
1229
1230 if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) {
1231 printk(KERN_INFO "sit init: Can't add protocol\n");
1232 return -EAGAIN;
1233 }
1234
1235 err = register_pernet_device(&sit_net_ops);
1236 if (err < 0)
1237 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1238
1239 return err;
1240 }
1241
1242 module_init(sit_init);
1243 module_exit(sit_cleanup);
1244 MODULE_LICENSE("GPL");
1245 MODULE_ALIAS("sit0");
Linux with added FPC-III support