Save sram context after changing MPU, DSP or core clocks
[linux-ginger.git] / net / ipv6 / sit.c
blobdbd19a78ca73ad32b048b8e9c8b89f3600195c90
1 /*
2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
3 * Linux INET6 implementation
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
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.
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
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>
36 #include <net/sock.h>
37 #include <net/snmp.h>
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>
57 This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
59 For comments look at net/ipv4/ip_gre.c --ANK
62 #define HASH_SIZE 16
63 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
65 static void ipip6_fb_tunnel_init(struct net_device *dev);
66 static void ipip6_tunnel_init(struct net_device *dev);
67 static void ipip6_tunnel_setup(struct net_device *dev);
69 static int sit_net_id;
70 struct sit_net {
71 struct ip_tunnel *tunnels_r_l[HASH_SIZE];
72 struct ip_tunnel *tunnels_r[HASH_SIZE];
73 struct ip_tunnel *tunnels_l[HASH_SIZE];
74 struct ip_tunnel *tunnels_wc[1];
75 struct ip_tunnel **tunnels[4];
77 struct net_device *fb_tunnel_dev;
80 static DEFINE_RWLOCK(ipip6_lock);
82 static struct ip_tunnel * ipip6_tunnel_lookup(struct net *net,
83 struct net_device *dev, __be32 remote, __be32 local)
85 unsigned h0 = HASH(remote);
86 unsigned h1 = HASH(local);
87 struct ip_tunnel *t;
88 struct sit_net *sitn = net_generic(net, sit_net_id);
90 for (t = sitn->tunnels_r_l[h0^h1]; t; t = t->next) {
91 if (local == t->parms.iph.saddr &&
92 remote == t->parms.iph.daddr &&
93 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
94 (t->dev->flags & IFF_UP))
95 return t;
97 for (t = sitn->tunnels_r[h0]; t; t = t->next) {
98 if (remote == t->parms.iph.daddr &&
99 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
100 (t->dev->flags & IFF_UP))
101 return t;
103 for (t = sitn->tunnels_l[h1]; t; t = t->next) {
104 if (local == t->parms.iph.saddr &&
105 (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
106 (t->dev->flags & IFF_UP))
107 return t;
109 t = sitn->tunnels_wc[0];
110 if ((t != NULL) && (t->dev->flags & IFF_UP))
111 return t;
112 return NULL;
115 static struct ip_tunnel **__ipip6_bucket(struct sit_net *sitn,
116 struct ip_tunnel_parm *parms)
118 __be32 remote = parms->iph.daddr;
119 __be32 local = parms->iph.saddr;
120 unsigned h = 0;
121 int prio = 0;
123 if (remote) {
124 prio |= 2;
125 h ^= HASH(remote);
127 if (local) {
128 prio |= 1;
129 h ^= HASH(local);
131 return &sitn->tunnels[prio][h];
134 static inline struct ip_tunnel **ipip6_bucket(struct sit_net *sitn,
135 struct ip_tunnel *t)
137 return __ipip6_bucket(sitn, &t->parms);
140 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
142 struct ip_tunnel **tp;
144 for (tp = ipip6_bucket(sitn, t); *tp; tp = &(*tp)->next) {
145 if (t == *tp) {
146 write_lock_bh(&ipip6_lock);
147 *tp = t->next;
148 write_unlock_bh(&ipip6_lock);
149 break;
154 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
156 struct ip_tunnel **tp = ipip6_bucket(sitn, t);
158 t->next = *tp;
159 write_lock_bh(&ipip6_lock);
160 *tp = t;
161 write_unlock_bh(&ipip6_lock);
164 static struct ip_tunnel * ipip6_tunnel_locate(struct net *net,
165 struct ip_tunnel_parm *parms, int create)
167 __be32 remote = parms->iph.daddr;
168 __be32 local = parms->iph.saddr;
169 struct ip_tunnel *t, **tp, *nt;
170 struct net_device *dev;
171 char name[IFNAMSIZ];
172 struct sit_net *sitn = net_generic(net, sit_net_id);
174 for (tp = __ipip6_bucket(sitn, parms); (t = *tp) != NULL; tp = &t->next) {
175 if (local == t->parms.iph.saddr &&
176 remote == t->parms.iph.daddr &&
177 parms->link == t->parms.link) {
178 if (create)
179 return NULL;
180 else
181 return t;
184 if (!create)
185 goto failed;
187 if (parms->name[0])
188 strlcpy(name, parms->name, IFNAMSIZ);
189 else
190 sprintf(name, "sit%%d");
192 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
193 if (dev == NULL)
194 return NULL;
196 dev_net_set(dev, net);
198 if (strchr(name, '%')) {
199 if (dev_alloc_name(dev, name) < 0)
200 goto failed_free;
203 nt = netdev_priv(dev);
205 nt->parms = *parms;
206 ipip6_tunnel_init(dev);
208 if (parms->i_flags & SIT_ISATAP)
209 dev->priv_flags |= IFF_ISATAP;
211 if (register_netdevice(dev) < 0)
212 goto failed_free;
214 dev_hold(dev);
216 ipip6_tunnel_link(sitn, nt);
217 return nt;
219 failed_free:
220 free_netdev(dev);
221 failed:
222 return NULL;
225 static struct ip_tunnel_prl_entry *
226 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
228 struct ip_tunnel_prl_entry *p = (struct ip_tunnel_prl_entry *)NULL;
230 for (p = t->prl; p; p = p->next)
231 if (p->addr == addr)
232 break;
233 return p;
237 static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
238 struct ip_tunnel_prl __user *a)
240 struct ip_tunnel_prl kprl, *kp;
241 struct ip_tunnel_prl_entry *prl;
242 unsigned int cmax, c = 0, ca, len;
243 int ret = 0;
245 if (copy_from_user(&kprl, a, sizeof(kprl)))
246 return -EFAULT;
247 cmax = kprl.datalen / sizeof(kprl);
248 if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
249 cmax = 1;
251 /* For simple GET or for root users,
252 * we try harder to allocate.
254 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
255 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
256 NULL;
258 read_lock(&ipip6_lock);
260 ca = t->prl_count < cmax ? t->prl_count : cmax;
262 if (!kp) {
263 /* We don't try hard to allocate much memory for
264 * non-root users.
265 * For root users, retry allocating enough memory for
266 * the answer.
268 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
269 if (!kp) {
270 ret = -ENOMEM;
271 goto out;
275 c = 0;
276 for (prl = t->prl; prl; prl = prl->next) {
277 if (c >= cmax)
278 break;
279 if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
280 continue;
281 kp[c].addr = prl->addr;
282 kp[c].flags = prl->flags;
283 c++;
284 if (kprl.addr != htonl(INADDR_ANY))
285 break;
287 out:
288 read_unlock(&ipip6_lock);
290 len = sizeof(*kp) * c;
291 ret = 0;
292 if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
293 ret = -EFAULT;
295 kfree(kp);
297 return ret;
300 static int
301 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
303 struct ip_tunnel_prl_entry *p;
304 int err = 0;
306 if (a->addr == htonl(INADDR_ANY))
307 return -EINVAL;
309 write_lock(&ipip6_lock);
311 for (p = t->prl; p; p = p->next) {
312 if (p->addr == a->addr) {
313 if (chg)
314 goto update;
315 err = -EEXIST;
316 goto out;
320 if (chg) {
321 err = -ENXIO;
322 goto out;
325 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
326 if (!p) {
327 err = -ENOBUFS;
328 goto out;
331 p->next = t->prl;
332 t->prl = p;
333 t->prl_count++;
334 update:
335 p->addr = a->addr;
336 p->flags = a->flags;
337 out:
338 write_unlock(&ipip6_lock);
339 return err;
342 static int
343 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
345 struct ip_tunnel_prl_entry *x, **p;
346 int err = 0;
348 write_lock(&ipip6_lock);
350 if (a && a->addr != htonl(INADDR_ANY)) {
351 for (p = &t->prl; *p; p = &(*p)->next) {
352 if ((*p)->addr == a->addr) {
353 x = *p;
354 *p = x->next;
355 kfree(x);
356 t->prl_count--;
357 goto out;
360 err = -ENXIO;
361 } else {
362 while (t->prl) {
363 x = t->prl;
364 t->prl = t->prl->next;
365 kfree(x);
366 t->prl_count--;
369 out:
370 write_unlock(&ipip6_lock);
371 return err;
374 static int
375 isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
377 struct ip_tunnel_prl_entry *p;
378 int ok = 1;
380 read_lock(&ipip6_lock);
381 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
382 if (p) {
383 if (p->flags & PRL_DEFAULT)
384 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
385 else
386 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
387 } else {
388 struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
389 if (ipv6_addr_is_isatap(addr6) &&
390 (addr6->s6_addr32[3] == iph->saddr) &&
391 ipv6_chk_prefix(addr6, t->dev))
392 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
393 else
394 ok = 0;
396 read_unlock(&ipip6_lock);
397 return ok;
400 static void ipip6_tunnel_uninit(struct net_device *dev)
402 struct net *net = dev_net(dev);
403 struct sit_net *sitn = net_generic(net, sit_net_id);
405 if (dev == sitn->fb_tunnel_dev) {
406 write_lock_bh(&ipip6_lock);
407 sitn->tunnels_wc[0] = NULL;
408 write_unlock_bh(&ipip6_lock);
409 dev_put(dev);
410 } else {
411 ipip6_tunnel_unlink(sitn, netdev_priv(dev));
412 ipip6_tunnel_del_prl(netdev_priv(dev), NULL);
413 dev_put(dev);
418 static int ipip6_err(struct sk_buff *skb, u32 info)
421 /* All the routers (except for Linux) return only
422 8 bytes of packet payload. It means, that precise relaying of
423 ICMP in the real Internet is absolutely infeasible.
425 struct iphdr *iph = (struct iphdr*)skb->data;
426 const int type = icmp_hdr(skb)->type;
427 const int code = icmp_hdr(skb)->code;
428 struct ip_tunnel *t;
429 int err;
431 switch (type) {
432 default:
433 case ICMP_PARAMETERPROB:
434 return 0;
436 case ICMP_DEST_UNREACH:
437 switch (code) {
438 case ICMP_SR_FAILED:
439 case ICMP_PORT_UNREACH:
440 /* Impossible event. */
441 return 0;
442 case ICMP_FRAG_NEEDED:
443 /* Soft state for pmtu is maintained by IP core. */
444 return 0;
445 default:
446 /* All others are translated to HOST_UNREACH.
447 rfc2003 contains "deep thoughts" about NET_UNREACH,
448 I believe they are just ether pollution. --ANK
450 break;
452 break;
453 case ICMP_TIME_EXCEEDED:
454 if (code != ICMP_EXC_TTL)
455 return 0;
456 break;
459 err = -ENOENT;
461 read_lock(&ipip6_lock);
462 t = ipip6_tunnel_lookup(dev_net(skb->dev),
463 skb->dev,
464 iph->daddr,
465 iph->saddr);
466 if (t == NULL || t->parms.iph.daddr == 0)
467 goto out;
469 err = 0;
470 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
471 goto out;
473 if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
474 t->err_count++;
475 else
476 t->err_count = 1;
477 t->err_time = jiffies;
478 out:
479 read_unlock(&ipip6_lock);
480 return err;
483 static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
485 if (INET_ECN_is_ce(iph->tos))
486 IP6_ECN_set_ce(ipv6_hdr(skb));
489 static int ipip6_rcv(struct sk_buff *skb)
491 struct iphdr *iph;
492 struct ip_tunnel *tunnel;
494 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
495 goto out;
497 iph = ip_hdr(skb);
499 read_lock(&ipip6_lock);
500 tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
501 iph->saddr, iph->daddr);
502 if (tunnel != NULL) {
503 secpath_reset(skb);
504 skb->mac_header = skb->network_header;
505 skb_reset_network_header(skb);
506 IPCB(skb)->flags = 0;
507 skb->protocol = htons(ETH_P_IPV6);
508 skb->pkt_type = PACKET_HOST;
510 if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
511 !isatap_chksrc(skb, iph, tunnel)) {
512 tunnel->dev->stats.rx_errors++;
513 read_unlock(&ipip6_lock);
514 kfree_skb(skb);
515 return 0;
517 tunnel->dev->stats.rx_packets++;
518 tunnel->dev->stats.rx_bytes += skb->len;
519 skb->dev = tunnel->dev;
520 skb_dst_drop(skb);
521 nf_reset(skb);
522 ipip6_ecn_decapsulate(iph, skb);
523 netif_rx(skb);
524 read_unlock(&ipip6_lock);
525 return 0;
528 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
529 read_unlock(&ipip6_lock);
530 out:
531 kfree_skb(skb);
532 return 0;
535 /* Returns the embedded IPv4 address if the IPv6 address
536 comes from 6to4 (RFC 3056) addr space */
538 static inline __be32 try_6to4(struct in6_addr *v6dst)
540 __be32 dst = 0;
542 if (v6dst->s6_addr16[0] == htons(0x2002)) {
543 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
544 memcpy(&dst, &v6dst->s6_addr16[1], 4);
546 return dst;
550 * This function assumes it is being called from dev_queue_xmit()
551 * and that skb is filled properly by that function.
554 static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
555 struct net_device *dev)
557 struct ip_tunnel *tunnel = netdev_priv(dev);
558 struct net_device_stats *stats = &tunnel->dev->stats;
559 struct iphdr *tiph = &tunnel->parms.iph;
560 struct ipv6hdr *iph6 = ipv6_hdr(skb);
561 u8 tos = tunnel->parms.iph.tos;
562 struct rtable *rt; /* Route to the other host */
563 struct net_device *tdev; /* Device to other host */
564 struct iphdr *iph; /* Our new IP header */
565 unsigned int max_headroom; /* The extra header space needed */
566 __be32 dst = tiph->daddr;
567 int mtu;
568 struct in6_addr *addr6;
569 int addr_type;
571 if (skb->protocol != htons(ETH_P_IPV6))
572 goto tx_error;
574 /* ISATAP (RFC4214) - must come before 6to4 */
575 if (dev->priv_flags & IFF_ISATAP) {
576 struct neighbour *neigh = NULL;
578 if (skb_dst(skb))
579 neigh = skb_dst(skb)->neighbour;
581 if (neigh == NULL) {
582 if (net_ratelimit())
583 printk(KERN_DEBUG "sit: nexthop == NULL\n");
584 goto tx_error;
587 addr6 = (struct in6_addr*)&neigh->primary_key;
588 addr_type = ipv6_addr_type(addr6);
590 if ((addr_type & IPV6_ADDR_UNICAST) &&
591 ipv6_addr_is_isatap(addr6))
592 dst = addr6->s6_addr32[3];
593 else
594 goto tx_error;
597 if (!dst)
598 dst = try_6to4(&iph6->daddr);
600 if (!dst) {
601 struct neighbour *neigh = NULL;
603 if (skb_dst(skb))
604 neigh = skb_dst(skb)->neighbour;
606 if (neigh == NULL) {
607 if (net_ratelimit())
608 printk(KERN_DEBUG "sit: nexthop == NULL\n");
609 goto tx_error;
612 addr6 = (struct in6_addr*)&neigh->primary_key;
613 addr_type = ipv6_addr_type(addr6);
615 if (addr_type == IPV6_ADDR_ANY) {
616 addr6 = &ipv6_hdr(skb)->daddr;
617 addr_type = ipv6_addr_type(addr6);
620 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
621 goto tx_error_icmp;
623 dst = addr6->s6_addr32[3];
627 struct flowi fl = { .nl_u = { .ip4_u =
628 { .daddr = dst,
629 .saddr = tiph->saddr,
630 .tos = RT_TOS(tos) } },
631 .oif = tunnel->parms.link,
632 .proto = IPPROTO_IPV6 };
633 if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
634 stats->tx_carrier_errors++;
635 goto tx_error_icmp;
638 if (rt->rt_type != RTN_UNICAST) {
639 ip_rt_put(rt);
640 stats->tx_carrier_errors++;
641 goto tx_error_icmp;
643 tdev = rt->u.dst.dev;
645 if (tdev == dev) {
646 ip_rt_put(rt);
647 stats->collisions++;
648 goto tx_error;
651 if (tiph->frag_off)
652 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
653 else
654 mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
656 if (mtu < 68) {
657 stats->collisions++;
658 ip_rt_put(rt);
659 goto tx_error;
661 if (mtu < IPV6_MIN_MTU)
662 mtu = IPV6_MIN_MTU;
663 if (tunnel->parms.iph.daddr && skb_dst(skb))
664 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
666 if (skb->len > mtu) {
667 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
668 ip_rt_put(rt);
669 goto tx_error;
672 if (tunnel->err_count > 0) {
673 if (time_before(jiffies,
674 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
675 tunnel->err_count--;
676 dst_link_failure(skb);
677 } else
678 tunnel->err_count = 0;
682 * Okay, now see if we can stuff it in the buffer as-is.
684 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
686 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
687 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
688 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
689 if (!new_skb) {
690 ip_rt_put(rt);
691 stats->tx_dropped++;
692 dev_kfree_skb(skb);
693 return NETDEV_TX_OK;
695 if (skb->sk)
696 skb_set_owner_w(new_skb, skb->sk);
697 dev_kfree_skb(skb);
698 skb = new_skb;
699 iph6 = ipv6_hdr(skb);
702 skb->transport_header = skb->network_header;
703 skb_push(skb, sizeof(struct iphdr));
704 skb_reset_network_header(skb);
705 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
706 IPCB(skb)->flags = 0;
707 skb_dst_drop(skb);
708 skb_dst_set(skb, &rt->u.dst);
711 * Push down and install the IPIP header.
714 iph = ip_hdr(skb);
715 iph->version = 4;
716 iph->ihl = sizeof(struct iphdr)>>2;
717 if (mtu > IPV6_MIN_MTU)
718 iph->frag_off = tiph->frag_off;
719 else
720 iph->frag_off = 0;
722 iph->protocol = IPPROTO_IPV6;
723 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
724 iph->daddr = rt->rt_dst;
725 iph->saddr = rt->rt_src;
727 if ((iph->ttl = tiph->ttl) == 0)
728 iph->ttl = iph6->hop_limit;
730 nf_reset(skb);
732 IPTUNNEL_XMIT();
733 return NETDEV_TX_OK;
735 tx_error_icmp:
736 dst_link_failure(skb);
737 tx_error:
738 stats->tx_errors++;
739 dev_kfree_skb(skb);
740 return NETDEV_TX_OK;
743 static void ipip6_tunnel_bind_dev(struct net_device *dev)
745 struct net_device *tdev = NULL;
746 struct ip_tunnel *tunnel;
747 struct iphdr *iph;
749 tunnel = netdev_priv(dev);
750 iph = &tunnel->parms.iph;
752 if (iph->daddr) {
753 struct flowi fl = { .nl_u = { .ip4_u =
754 { .daddr = iph->daddr,
755 .saddr = iph->saddr,
756 .tos = RT_TOS(iph->tos) } },
757 .oif = tunnel->parms.link,
758 .proto = IPPROTO_IPV6 };
759 struct rtable *rt;
760 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
761 tdev = rt->u.dst.dev;
762 ip_rt_put(rt);
764 dev->flags |= IFF_POINTOPOINT;
767 if (!tdev && tunnel->parms.link)
768 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
770 if (tdev) {
771 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
772 dev->mtu = tdev->mtu - sizeof(struct iphdr);
773 if (dev->mtu < IPV6_MIN_MTU)
774 dev->mtu = IPV6_MIN_MTU;
776 dev->iflink = tunnel->parms.link;
779 static int
780 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
782 int err = 0;
783 struct ip_tunnel_parm p;
784 struct ip_tunnel_prl prl;
785 struct ip_tunnel *t;
786 struct net *net = dev_net(dev);
787 struct sit_net *sitn = net_generic(net, sit_net_id);
789 switch (cmd) {
790 case SIOCGETTUNNEL:
791 t = NULL;
792 if (dev == sitn->fb_tunnel_dev) {
793 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
794 err = -EFAULT;
795 break;
797 t = ipip6_tunnel_locate(net, &p, 0);
799 if (t == NULL)
800 t = netdev_priv(dev);
801 memcpy(&p, &t->parms, sizeof(p));
802 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
803 err = -EFAULT;
804 break;
806 case SIOCADDTUNNEL:
807 case SIOCCHGTUNNEL:
808 err = -EPERM;
809 if (!capable(CAP_NET_ADMIN))
810 goto done;
812 err = -EFAULT;
813 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
814 goto done;
816 err = -EINVAL;
817 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
818 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
819 goto done;
820 if (p.iph.ttl)
821 p.iph.frag_off |= htons(IP_DF);
823 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
825 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
826 if (t != NULL) {
827 if (t->dev != dev) {
828 err = -EEXIST;
829 break;
831 } else {
832 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
833 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
834 err = -EINVAL;
835 break;
837 t = netdev_priv(dev);
838 ipip6_tunnel_unlink(sitn, t);
839 t->parms.iph.saddr = p.iph.saddr;
840 t->parms.iph.daddr = p.iph.daddr;
841 memcpy(dev->dev_addr, &p.iph.saddr, 4);
842 memcpy(dev->broadcast, &p.iph.daddr, 4);
843 ipip6_tunnel_link(sitn, t);
844 netdev_state_change(dev);
848 if (t) {
849 err = 0;
850 if (cmd == SIOCCHGTUNNEL) {
851 t->parms.iph.ttl = p.iph.ttl;
852 t->parms.iph.tos = p.iph.tos;
853 if (t->parms.link != p.link) {
854 t->parms.link = p.link;
855 ipip6_tunnel_bind_dev(dev);
856 netdev_state_change(dev);
859 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
860 err = -EFAULT;
861 } else
862 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
863 break;
865 case SIOCDELTUNNEL:
866 err = -EPERM;
867 if (!capable(CAP_NET_ADMIN))
868 goto done;
870 if (dev == sitn->fb_tunnel_dev) {
871 err = -EFAULT;
872 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
873 goto done;
874 err = -ENOENT;
875 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
876 goto done;
877 err = -EPERM;
878 if (t == netdev_priv(sitn->fb_tunnel_dev))
879 goto done;
880 dev = t->dev;
882 unregister_netdevice(dev);
883 err = 0;
884 break;
886 case SIOCGETPRL:
887 err = -EINVAL;
888 if (dev == sitn->fb_tunnel_dev)
889 goto done;
890 err = -ENOENT;
891 if (!(t = netdev_priv(dev)))
892 goto done;
893 err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
894 break;
896 case SIOCADDPRL:
897 case SIOCDELPRL:
898 case SIOCCHGPRL:
899 err = -EPERM;
900 if (!capable(CAP_NET_ADMIN))
901 goto done;
902 err = -EINVAL;
903 if (dev == sitn->fb_tunnel_dev)
904 goto done;
905 err = -EFAULT;
906 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
907 goto done;
908 err = -ENOENT;
909 if (!(t = netdev_priv(dev)))
910 goto done;
912 switch (cmd) {
913 case SIOCDELPRL:
914 err = ipip6_tunnel_del_prl(t, &prl);
915 break;
916 case SIOCADDPRL:
917 case SIOCCHGPRL:
918 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
919 break;
921 netdev_state_change(dev);
922 break;
924 default:
925 err = -EINVAL;
928 done:
929 return err;
932 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
934 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
935 return -EINVAL;
936 dev->mtu = new_mtu;
937 return 0;
940 static const struct net_device_ops ipip6_netdev_ops = {
941 .ndo_uninit = ipip6_tunnel_uninit,
942 .ndo_start_xmit = ipip6_tunnel_xmit,
943 .ndo_do_ioctl = ipip6_tunnel_ioctl,
944 .ndo_change_mtu = ipip6_tunnel_change_mtu,
947 static void ipip6_tunnel_setup(struct net_device *dev)
949 dev->netdev_ops = &ipip6_netdev_ops;
950 dev->destructor = free_netdev;
952 dev->type = ARPHRD_SIT;
953 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
954 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
955 dev->flags = IFF_NOARP;
956 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
957 dev->iflink = 0;
958 dev->addr_len = 4;
959 dev->features |= NETIF_F_NETNS_LOCAL;
962 static void ipip6_tunnel_init(struct net_device *dev)
964 struct ip_tunnel *tunnel = netdev_priv(dev);
966 tunnel->dev = dev;
967 strcpy(tunnel->parms.name, dev->name);
969 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
970 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
972 ipip6_tunnel_bind_dev(dev);
975 static void ipip6_fb_tunnel_init(struct net_device *dev)
977 struct ip_tunnel *tunnel = netdev_priv(dev);
978 struct iphdr *iph = &tunnel->parms.iph;
979 struct net *net = dev_net(dev);
980 struct sit_net *sitn = net_generic(net, sit_net_id);
982 tunnel->dev = dev;
983 strcpy(tunnel->parms.name, dev->name);
985 iph->version = 4;
986 iph->protocol = IPPROTO_IPV6;
987 iph->ihl = 5;
988 iph->ttl = 64;
990 dev_hold(dev);
991 sitn->tunnels_wc[0] = tunnel;
994 static struct xfrm_tunnel sit_handler = {
995 .handler = ipip6_rcv,
996 .err_handler = ipip6_err,
997 .priority = 1,
1000 static void sit_destroy_tunnels(struct sit_net *sitn)
1002 int prio;
1004 for (prio = 1; prio < 4; prio++) {
1005 int h;
1006 for (h = 0; h < HASH_SIZE; h++) {
1007 struct ip_tunnel *t;
1008 while ((t = sitn->tunnels[prio][h]) != NULL)
1009 unregister_netdevice(t->dev);
1014 static int sit_init_net(struct net *net)
1016 int err;
1017 struct sit_net *sitn;
1019 err = -ENOMEM;
1020 sitn = kzalloc(sizeof(struct sit_net), GFP_KERNEL);
1021 if (sitn == NULL)
1022 goto err_alloc;
1024 err = net_assign_generic(net, sit_net_id, sitn);
1025 if (err < 0)
1026 goto err_assign;
1028 sitn->tunnels[0] = sitn->tunnels_wc;
1029 sitn->tunnels[1] = sitn->tunnels_l;
1030 sitn->tunnels[2] = sitn->tunnels_r;
1031 sitn->tunnels[3] = sitn->tunnels_r_l;
1033 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1034 ipip6_tunnel_setup);
1035 if (!sitn->fb_tunnel_dev) {
1036 err = -ENOMEM;
1037 goto err_alloc_dev;
1039 dev_net_set(sitn->fb_tunnel_dev, net);
1041 ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
1043 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1044 goto err_reg_dev;
1046 return 0;
1048 err_reg_dev:
1049 dev_put(sitn->fb_tunnel_dev);
1050 free_netdev(sitn->fb_tunnel_dev);
1051 err_alloc_dev:
1052 /* nothing */
1053 err_assign:
1054 kfree(sitn);
1055 err_alloc:
1056 return err;
1059 static void sit_exit_net(struct net *net)
1061 struct sit_net *sitn;
1063 sitn = net_generic(net, sit_net_id);
1064 rtnl_lock();
1065 sit_destroy_tunnels(sitn);
1066 unregister_netdevice(sitn->fb_tunnel_dev);
1067 rtnl_unlock();
1068 kfree(sitn);
1071 static struct pernet_operations sit_net_ops = {
1072 .init = sit_init_net,
1073 .exit = sit_exit_net,
1076 static void __exit sit_cleanup(void)
1078 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1080 unregister_pernet_gen_device(sit_net_id, &sit_net_ops);
1083 static int __init sit_init(void)
1085 int err;
1087 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
1089 if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) {
1090 printk(KERN_INFO "sit init: Can't add protocol\n");
1091 return -EAGAIN;
1094 err = register_pernet_gen_device(&sit_net_id, &sit_net_ops);
1095 if (err < 0)
1096 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1098 return err;
1101 module_init(sit_init);
1102 module_exit(sit_cleanup);
1103 MODULE_LICENSE("GPL");
1104 MODULE_ALIAS("sit0");