2 * IPv6 over IPv6 tunnel device
3 * Linux INET6 implementation
6 * Ville Nuorvala <vnuorval@tcs.hut.fi>
11 * linux/net/ipv6/sit.c
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
22 #include <linux/module.h>
23 #include <linux/capability.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/sockios.h>
30 #include <linux/if_tunnel.h>
31 #include <linux/net.h>
32 #include <linux/in6.h>
33 #include <linux/netdevice.h>
34 #include <linux/if_arp.h>
35 #include <linux/icmpv6.h>
36 #include <linux/init.h>
37 #include <linux/route.h>
38 #include <linux/rtnetlink.h>
39 #include <linux/netfilter_ipv6.h>
41 #include <asm/uaccess.h>
42 #include <asm/atomic.h>
46 #include <net/ip6_route.h>
47 #include <net/addrconf.h>
48 #include <net/ip6_tunnel.h>
50 #include <net/dsfield.h>
51 #include <net/inet_ecn.h>
53 MODULE_AUTHOR("Ville Nuorvala");
54 MODULE_DESCRIPTION("IPv6-in-IPv6 tunnel");
55 MODULE_LICENSE("GPL");
57 #define IPV6_TLV_TEL_DST_SIZE 8
60 #define IP6_TNL_TRACE(x...) printk(KERN_DEBUG "%s:" x "\n", __FUNCTION__)
62 #define IP6_TNL_TRACE(x...) do {;} while(0)
65 #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK)
69 #define HASH(addr) ((__force u32)((addr)->s6_addr32[0] ^ (addr)->s6_addr32[1] ^ \
70 (addr)->s6_addr32[2] ^ (addr)->s6_addr32[3]) & \
73 static int ip6ip6_fb_tnl_dev_init(struct net_device *dev);
74 static int ip6ip6_tnl_dev_init(struct net_device *dev);
75 static void ip6ip6_tnl_dev_setup(struct net_device *dev);
77 /* the IPv6 tunnel fallback device */
78 static struct net_device *ip6ip6_fb_tnl_dev;
81 /* lists for storing tunnels in use */
82 static struct ip6_tnl *tnls_r_l[HASH_SIZE];
83 static struct ip6_tnl *tnls_wc[1];
84 static struct ip6_tnl **tnls[2] = { tnls_wc, tnls_r_l };
86 /* lock for the tunnel lists */
87 static DEFINE_RWLOCK(ip6ip6_lock);
89 static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
91 struct dst_entry *dst = t->dst_cache;
93 if (dst && dst->obsolete &&
94 dst->ops->check(dst, t->dst_cookie) == NULL) {
103 static inline void ip6_tnl_dst_reset(struct ip6_tnl *t)
105 dst_release(t->dst_cache);
109 static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
111 struct rt6_info *rt = (struct rt6_info *) dst;
112 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
113 dst_release(t->dst_cache);
118 * ip6ip6_tnl_lookup - fetch tunnel matching the end-point addresses
119 * @remote: the address of the tunnel exit-point
120 * @local: the address of the tunnel entry-point
123 * tunnel matching given end-points if found,
124 * else fallback tunnel if its device is up,
128 static struct ip6_tnl *
129 ip6ip6_tnl_lookup(struct in6_addr *remote, struct in6_addr *local)
131 unsigned h0 = HASH(remote);
132 unsigned h1 = HASH(local);
135 for (t = tnls_r_l[h0 ^ h1]; t; t = t->next) {
136 if (ipv6_addr_equal(local, &t->parms.laddr) &&
137 ipv6_addr_equal(remote, &t->parms.raddr) &&
138 (t->dev->flags & IFF_UP))
141 if ((t = tnls_wc[0]) != NULL && (t->dev->flags & IFF_UP))
148 * ip6ip6_bucket - get head of list matching given tunnel parameters
149 * @p: parameters containing tunnel end-points
152 * ip6ip6_bucket() returns the head of the list matching the
153 * &struct in6_addr entries laddr and raddr in @p.
155 * Return: head of IPv6 tunnel list
158 static struct ip6_tnl **
159 ip6ip6_bucket(struct ip6_tnl_parm *p)
161 struct in6_addr *remote = &p->raddr;
162 struct in6_addr *local = &p->laddr;
166 if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
168 h = HASH(remote) ^ HASH(local);
170 return &tnls[prio][h];
174 * ip6ip6_tnl_link - add tunnel to hash table
175 * @t: tunnel to be added
179 ip6ip6_tnl_link(struct ip6_tnl *t)
181 struct ip6_tnl **tp = ip6ip6_bucket(&t->parms);
184 write_lock_bh(&ip6ip6_lock);
186 write_unlock_bh(&ip6ip6_lock);
190 * ip6ip6_tnl_unlink - remove tunnel from hash table
191 * @t: tunnel to be removed
195 ip6ip6_tnl_unlink(struct ip6_tnl *t)
199 for (tp = ip6ip6_bucket(&t->parms); *tp; tp = &(*tp)->next) {
201 write_lock_bh(&ip6ip6_lock);
203 write_unlock_bh(&ip6ip6_lock);
210 * ip6_tnl_create() - create a new tunnel
211 * @p: tunnel parameters
212 * @pt: pointer to new tunnel
215 * Create tunnel matching given parameters.
218 * created tunnel or NULL
221 static struct ip6_tnl *ip6_tnl_create(struct ip6_tnl_parm *p)
223 struct net_device *dev;
229 strlcpy(name, p->name, IFNAMSIZ);
232 for (i = 1; i < IP6_TNL_MAX; i++) {
233 sprintf(name, "ip6tnl%d", i);
234 if (__dev_get_by_name(name) == NULL)
237 if (i == IP6_TNL_MAX)
240 dev = alloc_netdev(sizeof (*t), name, ip6ip6_tnl_dev_setup);
244 t = netdev_priv(dev);
245 dev->init = ip6ip6_tnl_dev_init;
248 if ((err = register_netdevice(dev)) < 0) {
260 * ip6ip6_tnl_locate - find or create tunnel matching given parameters
261 * @p: tunnel parameters
262 * @create: != 0 if allowed to create new tunnel if no match found
265 * ip6ip6_tnl_locate() first tries to locate an existing tunnel
266 * based on @parms. If this is unsuccessful, but @create is set a new
267 * tunnel device is created and registered for use.
270 * matching tunnel or NULL
273 static struct ip6_tnl *ip6ip6_tnl_locate(struct ip6_tnl_parm *p, int create)
275 struct in6_addr *remote = &p->raddr;
276 struct in6_addr *local = &p->laddr;
279 for (t = *ip6ip6_bucket(p); t; t = t->next) {
280 if (ipv6_addr_equal(local, &t->parms.laddr) &&
281 ipv6_addr_equal(remote, &t->parms.raddr))
286 return ip6_tnl_create(p);
290 * ip6ip6_tnl_dev_uninit - tunnel device uninitializer
291 * @dev: the device to be destroyed
294 * ip6ip6_tnl_dev_uninit() removes tunnel from its list
298 ip6ip6_tnl_dev_uninit(struct net_device *dev)
300 struct ip6_tnl *t = netdev_priv(dev);
302 if (dev == ip6ip6_fb_tnl_dev) {
303 write_lock_bh(&ip6ip6_lock);
305 write_unlock_bh(&ip6ip6_lock);
307 ip6ip6_tnl_unlink(t);
309 ip6_tnl_dst_reset(t);
314 * parse_tvl_tnl_enc_lim - handle encapsulation limit option
315 * @skb: received socket buffer
318 * 0 if none was found,
319 * else index to encapsulation limit
323 parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
325 struct ipv6hdr *ipv6h = (struct ipv6hdr *) raw;
326 __u8 nexthdr = ipv6h->nexthdr;
327 __u16 off = sizeof (*ipv6h);
329 while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) {
331 struct ipv6_opt_hdr *hdr;
332 if (raw + off + sizeof (*hdr) > skb->data &&
333 !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr)))
336 hdr = (struct ipv6_opt_hdr *) (raw + off);
337 if (nexthdr == NEXTHDR_FRAGMENT) {
338 struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr;
339 if (frag_hdr->frag_off)
342 } else if (nexthdr == NEXTHDR_AUTH) {
343 optlen = (hdr->hdrlen + 2) << 2;
345 optlen = ipv6_optlen(hdr);
347 if (nexthdr == NEXTHDR_DEST) {
350 struct ipv6_tlv_tnl_enc_lim *tel;
352 /* No more room for encapsulation limit */
353 if (i + sizeof (*tel) > off + optlen)
356 tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i];
357 /* return index of option if found and valid */
358 if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT &&
361 /* else jump to next option */
363 i += tel->length + 2;
368 nexthdr = hdr->nexthdr;
375 * ip6ip6_err - tunnel error handler
378 * ip6ip6_err() should handle errors in the tunnel according
379 * to the specifications in RFC 2473.
383 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
384 int type, int code, int offset, __be32 info)
386 struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data;
389 int rel_type = ICMPV6_DEST_UNREACH;
390 int rel_code = ICMPV6_ADDR_UNREACH;
395 /* If the packet doesn't contain the original IPv6 header we are
396 in trouble since we might need the source address for further
397 processing of the error. */
399 read_lock(&ip6ip6_lock);
400 if ((t = ip6ip6_tnl_lookup(&ipv6h->daddr, &ipv6h->saddr)) == NULL)
407 struct ipv6_tlv_tnl_enc_lim *tel;
409 case ICMPV6_DEST_UNREACH:
412 "%s: Path to destination invalid "
413 "or inactive!\n", t->parms.name);
416 case ICMPV6_TIME_EXCEED:
417 if (code == ICMPV6_EXC_HOPLIMIT) {
420 "%s: Too small hop limit or "
421 "routing loop in tunnel!\n",
426 case ICMPV6_PARAMPROB:
427 /* ignore if parameter problem not caused by a tunnel
428 encapsulation limit sub-option */
429 if (code != ICMPV6_HDR_FIELD) {
432 teli = parse_tlv_tnl_enc_lim(skb, skb->data);
434 if (teli && teli == ntohl(info) - 2) {
435 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
436 if (tel->encap_limit == 0) {
439 "%s: Too small encapsulation "
440 "limit or routing loop in "
441 "tunnel!\n", t->parms.name);
446 case ICMPV6_PKT_TOOBIG:
447 mtu = ntohl(info) - offset;
448 if (mtu < IPV6_MIN_MTU)
452 if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) {
453 rel_type = ICMPV6_PKT_TOOBIG;
460 if (rel_msg && pskb_may_pull(skb, offset + sizeof (*ipv6h))) {
462 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
466 dst_release(skb2->dst);
468 skb_pull(skb2, offset);
469 skb2->nh.raw = skb2->data;
471 /* Try to guess incoming interface */
472 rt = rt6_lookup(&skb2->nh.ipv6h->saddr, NULL, 0, 0);
474 if (rt && rt->rt6i_dev)
475 skb2->dev = rt->rt6i_dev;
477 icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
480 dst_release(&rt->u.dst);
485 read_unlock(&ip6ip6_lock);
489 static inline void ip6ip6_ecn_decapsulate(struct ipv6hdr *outer_iph,
492 struct ipv6hdr *inner_iph = skb->nh.ipv6h;
494 if (INET_ECN_is_ce(ipv6_get_dsfield(outer_iph)))
495 IP6_ECN_set_ce(inner_iph);
499 * ip6ip6_rcv - decapsulate IPv6 packet and retransmit it locally
500 * @skb: received socket buffer
506 ip6ip6_rcv(struct sk_buff *skb)
508 struct ipv6hdr *ipv6h;
511 ipv6h = skb->nh.ipv6h;
513 read_lock(&ip6ip6_lock);
515 if ((t = ip6ip6_tnl_lookup(&ipv6h->saddr, &ipv6h->daddr)) != NULL) {
516 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
517 read_unlock(&ip6ip6_lock);
521 if (!(t->parms.flags & IP6_TNL_F_CAP_RCV)) {
522 t->stat.rx_dropped++;
523 read_unlock(&ip6ip6_lock);
527 skb->mac.raw = skb->nh.raw;
528 skb->nh.raw = skb->data;
529 skb->protocol = htons(ETH_P_IPV6);
530 skb->pkt_type = PACKET_HOST;
531 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
533 dst_release(skb->dst);
536 if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY)
537 ipv6_copy_dscp(ipv6h, skb->nh.ipv6h);
538 ip6ip6_ecn_decapsulate(ipv6h, skb);
539 t->stat.rx_packets++;
540 t->stat.rx_bytes += skb->len;
542 read_unlock(&ip6ip6_lock);
545 read_unlock(&ip6ip6_lock);
553 static inline struct ipv6_txoptions *create_tel(__u8 encap_limit)
555 struct ipv6_tlv_tnl_enc_lim *tel;
556 struct ipv6_txoptions *opt;
559 int opt_len = sizeof(*opt) + 8;
561 if (!(opt = kzalloc(opt_len, GFP_ATOMIC))) {
564 opt->tot_len = opt_len;
565 opt->dst0opt = (struct ipv6_opt_hdr *) (opt + 1);
568 tel = (struct ipv6_tlv_tnl_enc_lim *) (opt->dst0opt + 1);
569 tel->type = IPV6_TLV_TNL_ENCAP_LIMIT;
571 tel->encap_limit = encap_limit;
573 raw = (__u8 *) opt->dst0opt;
574 raw[5] = IPV6_TLV_PADN;
581 * ip6ip6_tnl_addr_conflict - compare packet addresses to tunnel's own
582 * @t: the outgoing tunnel device
583 * @hdr: IPv6 header from the incoming packet
586 * Avoid trivial tunneling loop by checking that tunnel exit-point
587 * doesn't match source of incoming packet.
595 ip6ip6_tnl_addr_conflict(struct ip6_tnl *t, struct ipv6hdr *hdr)
597 return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
601 * ip6ip6_tnl_xmit - encapsulate packet and send
602 * @skb: the outgoing socket buffer
603 * @dev: the outgoing tunnel device
606 * Build new header and do some sanity checks on the packet before sending
614 ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
616 struct ip6_tnl *t = netdev_priv(dev);
617 struct net_device_stats *stats = &t->stat;
618 struct ipv6hdr *ipv6h = skb->nh.ipv6h;
619 struct ipv6_txoptions *opt = NULL;
620 int encap_limit = -1;
623 struct dst_entry *dst;
624 struct net_device *tdev;
626 int max_headroom = sizeof(struct ipv6hdr);
632 if (t->recursion++) {
636 if (skb->protocol != htons(ETH_P_IPV6) ||
637 !(t->parms.flags & IP6_TNL_F_CAP_XMIT) ||
638 ip6ip6_tnl_addr_conflict(t, ipv6h)) {
641 if ((offset = parse_tlv_tnl_enc_lim(skb, skb->nh.raw)) > 0) {
642 struct ipv6_tlv_tnl_enc_lim *tel;
643 tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->nh.raw[offset];
644 if (tel->encap_limit == 0) {
645 icmpv6_send(skb, ICMPV6_PARAMPROB,
646 ICMPV6_HDR_FIELD, offset + 2, skb->dev);
649 encap_limit = tel->encap_limit - 1;
650 } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
651 encap_limit = t->parms.encap_limit;
653 memcpy(&fl, &t->fl, sizeof (fl));
656 dsfield = ipv6_get_dsfield(ipv6h);
657 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS))
658 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
659 if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL))
660 fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK);
662 if (encap_limit >= 0 && (opt = create_tel(encap_limit)) == NULL)
665 if ((dst = ip6_tnl_dst_check(t)) != NULL)
668 dst = ip6_route_output(NULL, &fl);
670 if (dst->error || xfrm_lookup(&dst, &fl, NULL, 0) < 0)
671 goto tx_err_link_failure;
680 "%s: Local routing loop detected!\n",
682 goto tx_err_dst_release;
684 mtu = dst_mtu(dst) - sizeof (*ipv6h);
689 if (mtu < IPV6_MIN_MTU)
691 if (skb->dst && mtu < dst_mtu(skb->dst)) {
692 struct rt6_info *rt = (struct rt6_info *) skb->dst;
693 rt->rt6i_flags |= RTF_MODIFIED;
694 rt->u.dst.metrics[RTAX_MTU-1] = mtu;
696 if (skb->len > mtu) {
697 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
698 goto tx_err_dst_release;
702 * Okay, now see if we can stuff it in the buffer as-is.
704 max_headroom += LL_RESERVED_SPACE(tdev);
706 if (skb_headroom(skb) < max_headroom ||
707 skb_cloned(skb) || skb_shared(skb)) {
708 struct sk_buff *new_skb;
710 if (!(new_skb = skb_realloc_headroom(skb, max_headroom)))
711 goto tx_err_dst_release;
714 skb_set_owner_w(new_skb, skb->sk);
718 dst_release(skb->dst);
719 skb->dst = dst_clone(dst);
721 skb->h.raw = skb->nh.raw;
724 ipv6_push_nfrag_opts(skb, opt, &proto, NULL);
726 skb->nh.raw = skb_push(skb, sizeof(struct ipv6hdr));
727 ipv6h = skb->nh.ipv6h;
728 *(__be32*)ipv6h = fl.fl6_flowlabel | htonl(0x60000000);
729 dsfield = INET_ECN_encapsulate(0, dsfield);
730 ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
731 ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
732 ipv6h->hop_limit = t->parms.hop_limit;
733 ipv6h->nexthdr = proto;
734 ipv6_addr_copy(&ipv6h->saddr, &fl.fl6_src);
735 ipv6_addr_copy(&ipv6h->daddr, &fl.fl6_dst);
738 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL,
739 skb->dst->dev, dst_output);
741 if (net_xmit_eval(err) == 0) {
742 stats->tx_bytes += pkt_len;
746 stats->tx_aborted_errors++;
748 ip6_tnl_dst_store(t, dst);
755 stats->tx_carrier_errors++;
756 dst_link_failure(skb);
768 static void ip6_tnl_set_cap(struct ip6_tnl *t)
770 struct ip6_tnl_parm *p = &t->parms;
771 struct in6_addr *laddr = &p->laddr;
772 struct in6_addr *raddr = &p->raddr;
773 int ltype = ipv6_addr_type(laddr);
774 int rtype = ipv6_addr_type(raddr);
776 p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV);
778 if (ltype != IPV6_ADDR_ANY && rtype != IPV6_ADDR_ANY &&
781 IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL|
782 IPV6_ADDR_MAPPED|IPV6_ADDR_RESERVED)) == IPV6_ADDR_UNICAST) {
783 struct net_device *ldev = NULL;
788 ldev = dev_get_by_index(p->link);
790 if (ltype&IPV6_ADDR_UNICAST && !ipv6_chk_addr(laddr, ldev, 0))
793 if (rtype&IPV6_ADDR_UNICAST && ipv6_chk_addr(raddr, NULL, 0))
797 if (ltype&IPV6_ADDR_UNICAST)
798 p->flags |= IP6_TNL_F_CAP_XMIT;
799 if (rtype&IPV6_ADDR_UNICAST)
800 p->flags |= IP6_TNL_F_CAP_RCV;
807 static void ip6ip6_tnl_link_config(struct ip6_tnl *t)
809 struct net_device *dev = t->dev;
810 struct ip6_tnl_parm *p = &t->parms;
811 struct flowi *fl = &t->fl;
813 memcpy(&dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
814 memcpy(&dev->broadcast, &p->raddr, sizeof(struct in6_addr));
816 /* Set up flowi template */
817 ipv6_addr_copy(&fl->fl6_src, &p->laddr);
818 ipv6_addr_copy(&fl->fl6_dst, &p->raddr);
820 fl->fl6_flowlabel = 0;
822 if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
823 fl->fl6_flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
824 if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
825 fl->fl6_flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
829 if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV)
830 dev->flags |= IFF_POINTOPOINT;
832 dev->flags &= ~IFF_POINTOPOINT;
834 dev->iflink = p->link;
836 if (p->flags & IP6_TNL_F_CAP_XMIT) {
837 struct rt6_info *rt = rt6_lookup(&p->raddr, &p->laddr,
844 dev->hard_header_len = rt->rt6i_dev->hard_header_len +
845 sizeof (struct ipv6hdr);
847 dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr);
849 if (dev->mtu < IPV6_MIN_MTU)
850 dev->mtu = IPV6_MIN_MTU;
852 dst_release(&rt->u.dst);
857 * ip6ip6_tnl_change - update the tunnel parameters
858 * @t: tunnel to be changed
859 * @p: tunnel configuration parameters
860 * @active: != 0 if tunnel is ready for use
863 * ip6ip6_tnl_change() updates the tunnel parameters
867 ip6ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p)
869 ipv6_addr_copy(&t->parms.laddr, &p->laddr);
870 ipv6_addr_copy(&t->parms.raddr, &p->raddr);
871 t->parms.flags = p->flags;
872 t->parms.hop_limit = p->hop_limit;
873 t->parms.encap_limit = p->encap_limit;
874 t->parms.flowinfo = p->flowinfo;
875 t->parms.link = p->link;
876 ip6_tnl_dst_reset(t);
877 ip6ip6_tnl_link_config(t);
882 * ip6ip6_tnl_ioctl - configure ipv6 tunnels from userspace
883 * @dev: virtual device associated with tunnel
884 * @ifr: parameters passed from userspace
885 * @cmd: command to be performed
888 * ip6ip6_tnl_ioctl() is used for managing IPv6 tunnels
891 * The possible commands are the following:
892 * %SIOCGETTUNNEL: get tunnel parameters for device
893 * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
894 * %SIOCCHGTUNNEL: change tunnel parameters to those given
895 * %SIOCDELTUNNEL: delete tunnel
897 * The fallback device "ip6tnl0", created during module
898 * initialization, can be used for creating other tunnel devices.
902 * %-EFAULT if unable to copy data to or from userspace,
903 * %-EPERM if current process hasn't %CAP_NET_ADMIN set
904 * %-EINVAL if passed tunnel parameters are invalid,
905 * %-EEXIST if changing a tunnel's parameters would cause a conflict
906 * %-ENODEV if attempting to change or delete a nonexisting device
910 ip6ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
913 struct ip6_tnl_parm p;
914 struct ip6_tnl *t = NULL;
918 if (dev == ip6ip6_fb_tnl_dev) {
919 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {
923 t = ip6ip6_tnl_locate(&p, 0);
926 t = netdev_priv(dev);
927 memcpy(&p, &t->parms, sizeof (p));
928 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {
935 if (!capable(CAP_NET_ADMIN))
938 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
941 if (p.proto != IPPROTO_IPV6)
943 t = ip6ip6_tnl_locate(&p, cmd == SIOCADDTUNNEL);
944 if (dev != ip6ip6_fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
951 t = netdev_priv(dev);
953 ip6ip6_tnl_unlink(t);
954 err = ip6ip6_tnl_change(t, &p);
956 netdev_state_change(dev);
960 if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p)))
964 err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
968 if (!capable(CAP_NET_ADMIN))
971 if (dev == ip6ip6_fb_tnl_dev) {
973 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
976 if ((t = ip6ip6_tnl_locate(&p, 0)) == NULL)
979 if (t->dev == ip6ip6_fb_tnl_dev)
983 err = unregister_netdevice(dev);
992 * ip6ip6_tnl_get_stats - return the stats for tunnel device
993 * @dev: virtual device associated with tunnel
995 * Return: stats for device
998 static struct net_device_stats *
999 ip6ip6_tnl_get_stats(struct net_device *dev)
1001 return &(((struct ip6_tnl *)netdev_priv(dev))->stat);
1005 * ip6ip6_tnl_change_mtu - change mtu manually for tunnel device
1006 * @dev: virtual device associated with tunnel
1007 * @new_mtu: the new mtu
1011 * %-EINVAL if mtu too small
1015 ip6ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
1017 if (new_mtu < IPV6_MIN_MTU) {
1025 * ip6ip6_tnl_dev_setup - setup virtual tunnel device
1026 * @dev: virtual device associated with tunnel
1029 * Initialize function pointers and device parameters
1032 static void ip6ip6_tnl_dev_setup(struct net_device *dev)
1034 SET_MODULE_OWNER(dev);
1035 dev->uninit = ip6ip6_tnl_dev_uninit;
1036 dev->destructor = free_netdev;
1037 dev->hard_start_xmit = ip6ip6_tnl_xmit;
1038 dev->get_stats = ip6ip6_tnl_get_stats;
1039 dev->do_ioctl = ip6ip6_tnl_ioctl;
1040 dev->change_mtu = ip6ip6_tnl_change_mtu;
1042 dev->type = ARPHRD_TUNNEL6;
1043 dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr);
1044 dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr);
1045 dev->flags |= IFF_NOARP;
1046 dev->addr_len = sizeof(struct in6_addr);
1051 * ip6ip6_tnl_dev_init_gen - general initializer for all tunnel devices
1052 * @dev: virtual device associated with tunnel
1056 ip6ip6_tnl_dev_init_gen(struct net_device *dev)
1058 struct ip6_tnl *t = netdev_priv(dev);
1059 t->fl.proto = IPPROTO_IPV6;
1061 strcpy(t->parms.name, dev->name);
1065 * ip6ip6_tnl_dev_init - initializer for all non fallback tunnel devices
1066 * @dev: virtual device associated with tunnel
1070 ip6ip6_tnl_dev_init(struct net_device *dev)
1072 struct ip6_tnl *t = netdev_priv(dev);
1073 ip6ip6_tnl_dev_init_gen(dev);
1074 ip6ip6_tnl_link_config(t);
1079 * ip6ip6_fb_tnl_dev_init - initializer for fallback tunnel device
1080 * @dev: fallback device
1086 ip6ip6_fb_tnl_dev_init(struct net_device *dev)
1088 struct ip6_tnl *t = netdev_priv(dev);
1089 ip6ip6_tnl_dev_init_gen(dev);
1095 static struct xfrm6_tunnel ip6ip6_handler = {
1096 .handler = ip6ip6_rcv,
1097 .err_handler = ip6ip6_err,
1102 * ip6_tunnel_init - register protocol and reserve needed resources
1104 * Return: 0 on success
1107 static int __init ip6_tunnel_init(void)
1111 if (xfrm6_tunnel_register(&ip6ip6_handler)) {
1112 printk(KERN_ERR "ip6ip6 init: can't register tunnel\n");
1115 ip6ip6_fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0",
1116 ip6ip6_tnl_dev_setup);
1118 if (!ip6ip6_fb_tnl_dev) {
1122 ip6ip6_fb_tnl_dev->init = ip6ip6_fb_tnl_dev_init;
1124 if ((err = register_netdev(ip6ip6_fb_tnl_dev))) {
1125 free_netdev(ip6ip6_fb_tnl_dev);
1130 xfrm6_tunnel_deregister(&ip6ip6_handler);
1134 static void __exit ip6ip6_destroy_tunnels(void)
1139 for (h = 0; h < HASH_SIZE; h++) {
1140 while ((t = tnls_r_l[h]) != NULL)
1141 unregister_netdevice(t->dev);
1145 unregister_netdevice(t->dev);
1149 * ip6_tunnel_cleanup - free resources and unregister protocol
1152 static void __exit ip6_tunnel_cleanup(void)
1154 if (xfrm6_tunnel_deregister(&ip6ip6_handler))
1155 printk(KERN_INFO "ip6ip6 close: can't deregister tunnel\n");
1158 ip6ip6_destroy_tunnels();
1162 module_init(ip6_tunnel_init);
1163 module_exit(ip6_tunnel_cleanup);