2 * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
3 * Linux INET6 implementation
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.
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>
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>
50 #include <net/inet_ecn.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
63 #define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
65 static int ipip6_fb_tunnel_init(struct net_device *dev);
66 static int ipip6_tunnel_init(struct net_device *dev);
67 static void ipip6_tunnel_setup(struct net_device *dev);
69 static int sit_net_id;
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 __be32 remote, __be32 local)
85 unsigned h0 = HASH(remote);
86 unsigned h1 = HASH(local);
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 && (t->dev->flags&IFF_UP))
95 for (t = sitn->tunnels_r[h0]; t; t = t->next) {
96 if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
99 for (t = sitn->tunnels_l[h1]; t; t = t->next) {
100 if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
103 if ((t = sitn->tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
108 static struct ip_tunnel **__ipip6_bucket(struct sit_net *sitn,
109 struct ip_tunnel_parm *parms)
111 __be32 remote = parms->iph.daddr;
112 __be32 local = parms->iph.saddr;
124 return &sitn->tunnels[prio][h];
127 static inline struct ip_tunnel **ipip6_bucket(struct sit_net *sitn,
130 return __ipip6_bucket(sitn, &t->parms);
133 static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
135 struct ip_tunnel **tp;
137 for (tp = ipip6_bucket(sitn, t); *tp; tp = &(*tp)->next) {
139 write_lock_bh(&ipip6_lock);
141 write_unlock_bh(&ipip6_lock);
147 static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
149 struct ip_tunnel **tp = ipip6_bucket(sitn, t);
152 write_lock_bh(&ipip6_lock);
154 write_unlock_bh(&ipip6_lock);
157 static struct ip_tunnel * ipip6_tunnel_locate(struct net *net,
158 struct ip_tunnel_parm *parms, int create)
160 __be32 remote = parms->iph.daddr;
161 __be32 local = parms->iph.saddr;
162 struct ip_tunnel *t, **tp, *nt;
163 struct net_device *dev;
165 struct sit_net *sitn = net_generic(net, sit_net_id);
167 for (tp = __ipip6_bucket(sitn, parms); (t = *tp) != NULL; tp = &t->next) {
168 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
175 strlcpy(name, parms->name, IFNAMSIZ);
177 sprintf(name, "sit%%d");
179 dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
183 dev_net_set(dev, net);
185 if (strchr(name, '%')) {
186 if (dev_alloc_name(dev, name) < 0)
190 nt = netdev_priv(dev);
191 dev->init = ipip6_tunnel_init;
194 if (parms->i_flags & SIT_ISATAP)
195 dev->priv_flags |= IFF_ISATAP;
197 if (register_netdevice(dev) < 0)
202 ipip6_tunnel_link(sitn, nt);
211 static struct ip_tunnel_prl_entry *
212 __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
214 struct ip_tunnel_prl_entry *p = (struct ip_tunnel_prl_entry *)NULL;
216 for (p = t->prl; p; p = p->next)
223 static int ipip6_tunnel_get_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
225 struct ip_tunnel_prl *kp;
226 struct ip_tunnel_prl_entry *prl;
227 unsigned int cmax, c = 0, ca, len;
230 cmax = a->datalen / sizeof(*a);
231 if (cmax > 1 && a->addr != htonl(INADDR_ANY))
234 /* For simple GET or for root users,
235 * we try harder to allocate.
237 kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
238 kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
241 read_lock(&ipip6_lock);
243 ca = t->prl_count < cmax ? t->prl_count : cmax;
246 /* We don't try hard to allocate much memory for
248 * For root users, retry allocating enough memory for
251 kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
259 for (prl = t->prl; prl; prl = prl->next) {
262 if (a->addr != htonl(INADDR_ANY) && prl->addr != a->addr)
264 kp[c].addr = prl->addr;
265 kp[c].flags = prl->flags;
267 if (a->addr != htonl(INADDR_ANY))
271 read_unlock(&ipip6_lock);
273 len = sizeof(*kp) * c;
274 ret = len ? copy_to_user(a->data, kp, len) : 0;
285 ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
287 struct ip_tunnel_prl_entry *p;
290 if (a->addr == htonl(INADDR_ANY))
293 write_lock(&ipip6_lock);
295 for (p = t->prl; p; p = p->next) {
296 if (p->addr == a->addr) {
309 p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
322 write_unlock(&ipip6_lock);
327 ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
329 struct ip_tunnel_prl_entry *x, **p;
332 write_lock(&ipip6_lock);
334 if (a && a->addr != htonl(INADDR_ANY)) {
335 for (p = &t->prl; *p; p = &(*p)->next) {
336 if ((*p)->addr == a->addr) {
348 t->prl = t->prl->next;
354 write_unlock(&ipip6_lock);
359 isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
361 struct ip_tunnel_prl_entry *p;
364 read_lock(&ipip6_lock);
365 p = __ipip6_tunnel_locate_prl(t, iph->saddr);
367 if (p->flags & PRL_DEFAULT)
368 skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
370 skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
372 struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
373 if (ipv6_addr_is_isatap(addr6) &&
374 (addr6->s6_addr32[3] == iph->saddr) &&
375 ipv6_chk_prefix(addr6, t->dev))
376 skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
380 read_unlock(&ipip6_lock);
384 static void ipip6_tunnel_uninit(struct net_device *dev)
386 struct net *net = dev_net(dev);
387 struct sit_net *sitn = net_generic(net, sit_net_id);
389 if (dev == sitn->fb_tunnel_dev) {
390 write_lock_bh(&ipip6_lock);
391 sitn->tunnels_wc[0] = NULL;
392 write_unlock_bh(&ipip6_lock);
395 ipip6_tunnel_unlink(sitn, netdev_priv(dev));
396 ipip6_tunnel_del_prl(netdev_priv(dev), NULL);
402 static int ipip6_err(struct sk_buff *skb, u32 info)
405 /* All the routers (except for Linux) return only
406 8 bytes of packet payload. It means, that precise relaying of
407 ICMP in the real Internet is absolutely infeasible.
409 struct iphdr *iph = (struct iphdr*)skb->data;
410 const int type = icmp_hdr(skb)->type;
411 const int code = icmp_hdr(skb)->code;
417 case ICMP_PARAMETERPROB:
420 case ICMP_DEST_UNREACH:
423 case ICMP_PORT_UNREACH:
424 /* Impossible event. */
426 case ICMP_FRAG_NEEDED:
427 /* Soft state for pmtu is maintained by IP core. */
430 /* All others are translated to HOST_UNREACH.
431 rfc2003 contains "deep thoughts" about NET_UNREACH,
432 I believe they are just ether pollution. --ANK
437 case ICMP_TIME_EXCEEDED:
438 if (code != ICMP_EXC_TTL)
445 read_lock(&ipip6_lock);
446 t = ipip6_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
447 if (t == NULL || t->parms.iph.daddr == 0)
451 if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
454 if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
458 t->err_time = jiffies;
460 read_unlock(&ipip6_lock);
464 static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
466 if (INET_ECN_is_ce(iph->tos))
467 IP6_ECN_set_ce(ipv6_hdr(skb));
470 static int ipip6_rcv(struct sk_buff *skb)
473 struct ip_tunnel *tunnel;
475 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
480 read_lock(&ipip6_lock);
481 if ((tunnel = ipip6_tunnel_lookup(dev_net(skb->dev),
482 iph->saddr, iph->daddr)) != NULL) {
484 skb->mac_header = skb->network_header;
485 skb_reset_network_header(skb);
486 IPCB(skb)->flags = 0;
487 skb->protocol = htons(ETH_P_IPV6);
488 skb->pkt_type = PACKET_HOST;
490 if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
491 !isatap_chksrc(skb, iph, tunnel)) {
492 tunnel->dev->stats.rx_errors++;
493 read_unlock(&ipip6_lock);
497 tunnel->dev->stats.rx_packets++;
498 tunnel->dev->stats.rx_bytes += skb->len;
499 skb->dev = tunnel->dev;
500 dst_release(skb->dst);
503 ipip6_ecn_decapsulate(iph, skb);
505 read_unlock(&ipip6_lock);
509 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
510 read_unlock(&ipip6_lock);
516 /* Returns the embedded IPv4 address if the IPv6 address
517 comes from 6to4 (RFC 3056) addr space */
519 static inline __be32 try_6to4(struct in6_addr *v6dst)
523 if (v6dst->s6_addr16[0] == htons(0x2002)) {
524 /* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
525 memcpy(&dst, &v6dst->s6_addr16[1], 4);
531 * This function assumes it is being called from dev_queue_xmit()
532 * and that skb is filled properly by that function.
535 static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
537 struct ip_tunnel *tunnel = netdev_priv(dev);
538 struct net_device_stats *stats = &tunnel->dev->stats;
539 struct iphdr *tiph = &tunnel->parms.iph;
540 struct ipv6hdr *iph6 = ipv6_hdr(skb);
541 u8 tos = tunnel->parms.iph.tos;
542 struct rtable *rt; /* Route to the other host */
543 struct net_device *tdev; /* Device to other host */
544 struct iphdr *iph; /* Our new IP header */
545 unsigned int max_headroom; /* The extra header space needed */
546 __be32 dst = tiph->daddr;
548 struct in6_addr *addr6;
551 if (tunnel->recursion++) {
556 if (skb->protocol != htons(ETH_P_IPV6))
559 /* ISATAP (RFC4214) - must come before 6to4 */
560 if (dev->priv_flags & IFF_ISATAP) {
561 struct neighbour *neigh = NULL;
564 neigh = skb->dst->neighbour;
568 printk(KERN_DEBUG "sit: nexthop == NULL\n");
572 addr6 = (struct in6_addr*)&neigh->primary_key;
573 addr_type = ipv6_addr_type(addr6);
575 if ((addr_type & IPV6_ADDR_UNICAST) &&
576 ipv6_addr_is_isatap(addr6))
577 dst = addr6->s6_addr32[3];
583 dst = try_6to4(&iph6->daddr);
586 struct neighbour *neigh = NULL;
589 neigh = skb->dst->neighbour;
593 printk(KERN_DEBUG "sit: nexthop == NULL\n");
597 addr6 = (struct in6_addr*)&neigh->primary_key;
598 addr_type = ipv6_addr_type(addr6);
600 if (addr_type == IPV6_ADDR_ANY) {
601 addr6 = &ipv6_hdr(skb)->daddr;
602 addr_type = ipv6_addr_type(addr6);
605 if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
608 dst = addr6->s6_addr32[3];
612 struct flowi fl = { .nl_u = { .ip4_u =
614 .saddr = tiph->saddr,
615 .tos = RT_TOS(tos) } },
616 .oif = tunnel->parms.link,
617 .proto = IPPROTO_IPV6 };
618 if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
619 stats->tx_carrier_errors++;
623 if (rt->rt_type != RTN_UNICAST) {
625 stats->tx_carrier_errors++;
628 tdev = rt->u.dst.dev;
637 mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
639 mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
646 if (mtu < IPV6_MIN_MTU)
648 if (tunnel->parms.iph.daddr && skb->dst)
649 skb->dst->ops->update_pmtu(skb->dst, mtu);
651 if (skb->len > mtu) {
652 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
657 if (tunnel->err_count > 0) {
658 if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
660 dst_link_failure(skb);
662 tunnel->err_count = 0;
666 * Okay, now see if we can stuff it in the buffer as-is.
668 max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
670 if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
671 (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
672 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
681 skb_set_owner_w(new_skb, skb->sk);
684 iph6 = ipv6_hdr(skb);
687 skb->transport_header = skb->network_header;
688 skb_push(skb, sizeof(struct iphdr));
689 skb_reset_network_header(skb);
690 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
691 IPCB(skb)->flags = 0;
692 dst_release(skb->dst);
693 skb->dst = &rt->u.dst;
696 * Push down and install the IPIP header.
701 iph->ihl = sizeof(struct iphdr)>>2;
702 if (mtu > IPV6_MIN_MTU)
703 iph->frag_off = htons(IP_DF);
707 iph->protocol = IPPROTO_IPV6;
708 iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
709 iph->daddr = rt->rt_dst;
710 iph->saddr = rt->rt_src;
712 if ((iph->ttl = tiph->ttl) == 0)
713 iph->ttl = iph6->hop_limit;
722 dst_link_failure(skb);
730 static void ipip6_tunnel_bind_dev(struct net_device *dev)
732 struct net_device *tdev = NULL;
733 struct ip_tunnel *tunnel;
736 tunnel = netdev_priv(dev);
737 iph = &tunnel->parms.iph;
740 struct flowi fl = { .nl_u = { .ip4_u =
741 { .daddr = iph->daddr,
743 .tos = RT_TOS(iph->tos) } },
744 .oif = tunnel->parms.link,
745 .proto = IPPROTO_IPV6 };
747 if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
748 tdev = rt->u.dst.dev;
751 dev->flags |= IFF_POINTOPOINT;
754 if (!tdev && tunnel->parms.link)
755 tdev = __dev_get_by_index(dev_net(dev), tunnel->parms.link);
758 dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
759 dev->mtu = tdev->mtu - sizeof(struct iphdr);
760 if (dev->mtu < IPV6_MIN_MTU)
761 dev->mtu = IPV6_MIN_MTU;
763 dev->iflink = tunnel->parms.link;
767 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
770 struct ip_tunnel_parm p;
771 struct ip_tunnel_prl prl;
773 struct net *net = dev_net(dev);
774 struct sit_net *sitn = net_generic(net, sit_net_id);
779 if (dev == sitn->fb_tunnel_dev) {
780 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
784 t = ipip6_tunnel_locate(net, &p, 0);
787 t = netdev_priv(dev);
788 memcpy(&p, &t->parms, sizeof(p));
789 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
796 if (!capable(CAP_NET_ADMIN))
800 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
804 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
805 p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
808 p.iph.frag_off |= htons(IP_DF);
810 t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
812 if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
819 if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
820 (!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
824 t = netdev_priv(dev);
825 ipip6_tunnel_unlink(sitn, t);
826 t->parms.iph.saddr = p.iph.saddr;
827 t->parms.iph.daddr = p.iph.daddr;
828 memcpy(dev->dev_addr, &p.iph.saddr, 4);
829 memcpy(dev->broadcast, &p.iph.daddr, 4);
830 ipip6_tunnel_link(sitn, t);
831 netdev_state_change(dev);
837 if (cmd == SIOCCHGTUNNEL) {
838 t->parms.iph.ttl = p.iph.ttl;
839 t->parms.iph.tos = p.iph.tos;
840 if (t->parms.link != p.link) {
841 t->parms.link = p.link;
842 ipip6_tunnel_bind_dev(dev);
843 netdev_state_change(dev);
846 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
849 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
854 if (!capable(CAP_NET_ADMIN))
857 if (dev == sitn->fb_tunnel_dev) {
859 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
862 if ((t = ipip6_tunnel_locate(net, &p, 0)) == NULL)
865 if (t == netdev_priv(sitn->fb_tunnel_dev))
869 unregister_netdevice(dev);
878 if (cmd != SIOCGETPRL && !capable(CAP_NET_ADMIN))
881 if (dev == sitn->fb_tunnel_dev)
884 if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
887 if (!(t = netdev_priv(dev)))
892 err = ipip6_tunnel_get_prl(t, &prl);
893 if (!err && copy_to_user(ifr->ifr_ifru.ifru_data,
898 err = ipip6_tunnel_del_prl(t, &prl);
902 err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
905 if (cmd != SIOCGETPRL)
906 netdev_state_change(dev);
917 static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
919 if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
925 static void ipip6_tunnel_setup(struct net_device *dev)
927 dev->uninit = ipip6_tunnel_uninit;
928 dev->destructor = free_netdev;
929 dev->hard_start_xmit = ipip6_tunnel_xmit;
930 dev->do_ioctl = ipip6_tunnel_ioctl;
931 dev->change_mtu = ipip6_tunnel_change_mtu;
933 dev->type = ARPHRD_SIT;
934 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
935 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
936 dev->flags = IFF_NOARP;
939 dev->features |= NETIF_F_NETNS_LOCAL;
942 static int ipip6_tunnel_init(struct net_device *dev)
944 struct ip_tunnel *tunnel;
946 tunnel = netdev_priv(dev);
949 strcpy(tunnel->parms.name, dev->name);
951 memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
952 memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
954 ipip6_tunnel_bind_dev(dev);
959 static int ipip6_fb_tunnel_init(struct net_device *dev)
961 struct ip_tunnel *tunnel = netdev_priv(dev);
962 struct iphdr *iph = &tunnel->parms.iph;
963 struct net *net = dev_net(dev);
964 struct sit_net *sitn = net_generic(net, sit_net_id);
967 strcpy(tunnel->parms.name, dev->name);
970 iph->protocol = IPPROTO_IPV6;
975 sitn->tunnels_wc[0] = tunnel;
979 static struct xfrm_tunnel sit_handler = {
980 .handler = ipip6_rcv,
981 .err_handler = ipip6_err,
985 static void sit_destroy_tunnels(struct sit_net *sitn)
989 for (prio = 1; prio < 4; prio++) {
991 for (h = 0; h < HASH_SIZE; h++) {
993 while ((t = sitn->tunnels[prio][h]) != NULL)
994 unregister_netdevice(t->dev);
999 static int sit_init_net(struct net *net)
1002 struct sit_net *sitn;
1005 sitn = kzalloc(sizeof(struct sit_net), GFP_KERNEL);
1009 err = net_assign_generic(net, sit_net_id, sitn);
1013 sitn->tunnels[0] = sitn->tunnels_wc;
1014 sitn->tunnels[1] = sitn->tunnels_l;
1015 sitn->tunnels[2] = sitn->tunnels_r;
1016 sitn->tunnels[3] = sitn->tunnels_r_l;
1018 sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
1019 ipip6_tunnel_setup);
1020 if (!sitn->fb_tunnel_dev) {
1025 sitn->fb_tunnel_dev->init = ipip6_fb_tunnel_init;
1026 dev_net_set(sitn->fb_tunnel_dev, net);
1028 if ((err = register_netdev(sitn->fb_tunnel_dev)))
1034 free_netdev(sitn->fb_tunnel_dev);
1043 static void sit_exit_net(struct net *net)
1045 struct sit_net *sitn;
1047 sitn = net_generic(net, sit_net_id);
1049 sit_destroy_tunnels(sitn);
1050 unregister_netdevice(sitn->fb_tunnel_dev);
1055 static struct pernet_operations sit_net_ops = {
1056 .init = sit_init_net,
1057 .exit = sit_exit_net,
1060 static void __exit sit_cleanup(void)
1062 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1064 unregister_pernet_gen_device(sit_net_id, &sit_net_ops);
1067 static int __init sit_init(void)
1071 printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
1073 if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) {
1074 printk(KERN_INFO "sit init: Can't add protocol\n");
1078 err = register_pernet_gen_device(&sit_net_id, &sit_net_ops);
1080 xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
1085 module_init(sit_init);
1086 module_exit(sit_cleanup);
1087 MODULE_LICENSE("GPL");
1088 MODULE_ALIAS("sit0");