![Denis V. Lunev](/assets/img/avatar_default.png)
Needed to propagate it down to the ip_route_output_flow. Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
951 lines
21 KiB
C
951 lines
21 KiB
C
/*
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* IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
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* Linux INET6 implementation
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*
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* Authors:
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* Pedro Roque <roque@di.fc.ul.pt>
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* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
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*
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* $Id: sit.c,v 1.53 2001/09/25 05:09:53 davem Exp $
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Changes:
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* Roger Venning <r.venning@telstra.com>: 6to4 support
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* Nate Thompson <nate@thebog.net>: 6to4 support
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* Fred L. Templin <fltemplin@acm.org>: isatap support
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*/
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#include <linux/module.h>
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#include <linux/capability.h>
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/socket.h>
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#include <linux/sockios.h>
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#include <linux/net.h>
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#include <linux/in6.h>
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#include <linux/netdevice.h>
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#include <linux/if_arp.h>
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#include <linux/icmp.h>
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#include <asm/uaccess.h>
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#include <linux/init.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/if_ether.h>
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#include <net/sock.h>
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#include <net/snmp.h>
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#include <net/ipv6.h>
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#include <net/protocol.h>
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#include <net/transp_v6.h>
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#include <net/ip6_fib.h>
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#include <net/ip6_route.h>
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#include <net/ndisc.h>
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#include <net/addrconf.h>
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#include <net/ip.h>
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#include <net/udp.h>
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#include <net/icmp.h>
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#include <net/ipip.h>
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#include <net/inet_ecn.h>
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#include <net/xfrm.h>
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#include <net/dsfield.h>
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/*
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This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
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For comments look at net/ipv4/ip_gre.c --ANK
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*/
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#define HASH_SIZE 16
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#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
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static int ipip6_fb_tunnel_init(struct net_device *dev);
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static int ipip6_tunnel_init(struct net_device *dev);
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static void ipip6_tunnel_setup(struct net_device *dev);
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static struct net_device *ipip6_fb_tunnel_dev;
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static struct ip_tunnel *tunnels_r_l[HASH_SIZE];
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static struct ip_tunnel *tunnels_r[HASH_SIZE];
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static struct ip_tunnel *tunnels_l[HASH_SIZE];
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static struct ip_tunnel *tunnels_wc[1];
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static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l };
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static DEFINE_RWLOCK(ipip6_lock);
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static struct ip_tunnel * ipip6_tunnel_lookup(__be32 remote, __be32 local)
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{
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unsigned h0 = HASH(remote);
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unsigned h1 = HASH(local);
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struct ip_tunnel *t;
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for (t = tunnels_r_l[h0^h1]; t; t = t->next) {
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if (local == t->parms.iph.saddr &&
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remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
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return t;
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}
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for (t = tunnels_r[h0]; t; t = t->next) {
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if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
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return t;
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}
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for (t = tunnels_l[h1]; t; t = t->next) {
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if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
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return t;
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}
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if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
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return t;
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return NULL;
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}
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static struct ip_tunnel **__ipip6_bucket(struct ip_tunnel_parm *parms)
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{
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__be32 remote = parms->iph.daddr;
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__be32 local = parms->iph.saddr;
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unsigned h = 0;
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int prio = 0;
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if (remote) {
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prio |= 2;
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h ^= HASH(remote);
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}
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if (local) {
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prio |= 1;
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h ^= HASH(local);
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}
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return &tunnels[prio][h];
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}
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static inline struct ip_tunnel **ipip6_bucket(struct ip_tunnel *t)
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{
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return __ipip6_bucket(&t->parms);
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}
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static void ipip6_tunnel_unlink(struct ip_tunnel *t)
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{
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struct ip_tunnel **tp;
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for (tp = ipip6_bucket(t); *tp; tp = &(*tp)->next) {
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if (t == *tp) {
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write_lock_bh(&ipip6_lock);
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*tp = t->next;
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write_unlock_bh(&ipip6_lock);
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break;
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}
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}
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}
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static void ipip6_tunnel_link(struct ip_tunnel *t)
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{
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struct ip_tunnel **tp = ipip6_bucket(t);
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t->next = *tp;
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write_lock_bh(&ipip6_lock);
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*tp = t;
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write_unlock_bh(&ipip6_lock);
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}
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static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int create)
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{
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__be32 remote = parms->iph.daddr;
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__be32 local = parms->iph.saddr;
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struct ip_tunnel *t, **tp, *nt;
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struct net_device *dev;
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char name[IFNAMSIZ];
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for (tp = __ipip6_bucket(parms); (t = *tp) != NULL; tp = &t->next) {
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if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
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return t;
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}
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if (!create)
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goto failed;
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if (parms->name[0])
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strlcpy(name, parms->name, IFNAMSIZ);
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else {
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int i;
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for (i=1; i<100; i++) {
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sprintf(name, "sit%d", i);
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if (__dev_get_by_name(&init_net, name) == NULL)
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break;
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}
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if (i==100)
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goto failed;
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}
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dev = alloc_netdev(sizeof(*t), name, ipip6_tunnel_setup);
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if (dev == NULL)
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return NULL;
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nt = netdev_priv(dev);
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dev->init = ipip6_tunnel_init;
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nt->parms = *parms;
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if (parms->i_flags & SIT_ISATAP)
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dev->priv_flags |= IFF_ISATAP;
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if (register_netdevice(dev) < 0) {
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free_netdev(dev);
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goto failed;
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}
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dev_hold(dev);
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ipip6_tunnel_link(nt);
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return nt;
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failed:
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return NULL;
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}
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static void ipip6_tunnel_uninit(struct net_device *dev)
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{
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if (dev == ipip6_fb_tunnel_dev) {
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write_lock_bh(&ipip6_lock);
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tunnels_wc[0] = NULL;
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write_unlock_bh(&ipip6_lock);
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dev_put(dev);
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} else {
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ipip6_tunnel_unlink(netdev_priv(dev));
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dev_put(dev);
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}
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}
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static int ipip6_err(struct sk_buff *skb, u32 info)
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{
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#ifndef I_WISH_WORLD_WERE_PERFECT
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/* It is not :-( All the routers (except for Linux) return only
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8 bytes of packet payload. It means, that precise relaying of
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ICMP in the real Internet is absolutely infeasible.
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*/
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struct iphdr *iph = (struct iphdr*)skb->data;
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const int type = icmp_hdr(skb)->type;
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const int code = icmp_hdr(skb)->code;
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struct ip_tunnel *t;
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int err;
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switch (type) {
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default:
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case ICMP_PARAMETERPROB:
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return 0;
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case ICMP_DEST_UNREACH:
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switch (code) {
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case ICMP_SR_FAILED:
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case ICMP_PORT_UNREACH:
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/* Impossible event. */
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return 0;
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case ICMP_FRAG_NEEDED:
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/* Soft state for pmtu is maintained by IP core. */
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return 0;
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default:
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/* All others are translated to HOST_UNREACH.
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rfc2003 contains "deep thoughts" about NET_UNREACH,
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I believe they are just ether pollution. --ANK
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*/
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break;
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}
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break;
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case ICMP_TIME_EXCEEDED:
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if (code != ICMP_EXC_TTL)
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return 0;
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break;
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}
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err = -ENOENT;
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read_lock(&ipip6_lock);
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t = ipip6_tunnel_lookup(iph->daddr, iph->saddr);
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if (t == NULL || t->parms.iph.daddr == 0)
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goto out;
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err = 0;
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if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
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goto out;
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if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
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t->err_count++;
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else
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t->err_count = 1;
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t->err_time = jiffies;
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out:
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read_unlock(&ipip6_lock);
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return err;
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#else
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struct iphdr *iph = (struct iphdr*)dp;
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int hlen = iph->ihl<<2;
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struct ipv6hdr *iph6;
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const int type = icmp_hdr(skb)->type;
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const int code = icmp_hdr(skb)->code;
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int rel_type = 0;
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int rel_code = 0;
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int rel_info = 0;
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struct sk_buff *skb2;
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struct rt6_info *rt6i;
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if (len < hlen + sizeof(struct ipv6hdr))
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return;
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iph6 = (struct ipv6hdr*)(dp + hlen);
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switch (type) {
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default:
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return;
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case ICMP_PARAMETERPROB:
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if (icmp_hdr(skb)->un.gateway < hlen)
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return;
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/* So... This guy found something strange INSIDE encapsulated
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packet. Well, he is fool, but what can we do ?
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*/
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rel_type = ICMPV6_PARAMPROB;
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rel_info = icmp_hdr(skb)->un.gateway - hlen;
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break;
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case ICMP_DEST_UNREACH:
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switch (code) {
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case ICMP_SR_FAILED:
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case ICMP_PORT_UNREACH:
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/* Impossible event. */
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return;
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case ICMP_FRAG_NEEDED:
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/* Too complicated case ... */
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return;
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default:
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/* All others are translated to HOST_UNREACH.
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rfc2003 contains "deep thoughts" about NET_UNREACH,
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I believe, it is just ether pollution. --ANK
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*/
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rel_type = ICMPV6_DEST_UNREACH;
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rel_code = ICMPV6_ADDR_UNREACH;
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break;
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}
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break;
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case ICMP_TIME_EXCEEDED:
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if (code != ICMP_EXC_TTL)
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return;
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rel_type = ICMPV6_TIME_EXCEED;
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rel_code = ICMPV6_EXC_HOPLIMIT;
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break;
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}
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/* Prepare fake skb to feed it to icmpv6_send */
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skb2 = skb_clone(skb, GFP_ATOMIC);
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if (skb2 == NULL)
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return 0;
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dst_release(skb2->dst);
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skb2->dst = NULL;
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skb_pull(skb2, skb->data - (u8*)iph6);
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skb_reset_network_header(skb2);
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/* Try to guess incoming interface */
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rt6i = rt6_lookup(&iph6->saddr, NULL, NULL, 0);
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if (rt6i && rt6i->rt6i_dev) {
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skb2->dev = rt6i->rt6i_dev;
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rt6i = rt6_lookup(&iph6->daddr, &iph6->saddr, NULL, 0);
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if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) {
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struct ip_tunnel *t = netdev_priv(rt6i->rt6i_dev);
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if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) {
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rel_type = ICMPV6_DEST_UNREACH;
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rel_code = ICMPV6_ADDR_UNREACH;
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}
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icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
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}
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}
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kfree_skb(skb2);
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return 0;
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#endif
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}
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static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
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{
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if (INET_ECN_is_ce(iph->tos))
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IP6_ECN_set_ce(ipv6_hdr(skb));
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}
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/* ISATAP (RFC4214) - check source address */
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static int
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isatap_srcok(struct sk_buff *skb, struct iphdr *iph, struct net_device *dev)
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{
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struct neighbour *neigh;
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struct dst_entry *dst;
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struct rt6_info *rt;
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struct flowi fl;
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struct in6_addr *addr6;
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struct in6_addr rtr;
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struct ipv6hdr *iph6;
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int ok = 0;
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/* from onlink default router */
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ipv6_addr_set(&rtr, htonl(0xFE800000), 0, 0, 0);
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ipv6_isatap_eui64(rtr.s6_addr + 8, iph->saddr);
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if ((rt = rt6_get_dflt_router(&rtr, dev))) {
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dst_release(&rt->u.dst);
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return 1;
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}
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iph6 = ipv6_hdr(skb);
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memset(&fl, 0, sizeof(fl));
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fl.proto = iph6->nexthdr;
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ipv6_addr_copy(&fl.fl6_dst, &iph6->saddr);
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fl.oif = dev->ifindex;
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security_skb_classify_flow(skb, &fl);
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dst = ip6_route_output(NULL, &fl);
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if (!dst->error && (dst->dev == dev) && (neigh = dst->neighbour)) {
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addr6 = (struct in6_addr*)&neigh->primary_key;
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/* from correct previous hop */
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if (ipv6_addr_is_isatap(addr6) &&
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(addr6->s6_addr32[3] == iph->saddr))
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ok = 1;
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}
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dst_release(dst);
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return ok;
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}
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static int ipip6_rcv(struct sk_buff *skb)
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{
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struct iphdr *iph;
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struct ip_tunnel *tunnel;
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if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
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goto out;
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iph = ip_hdr(skb);
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read_lock(&ipip6_lock);
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if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
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secpath_reset(skb);
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skb->mac_header = skb->network_header;
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skb_reset_network_header(skb);
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IPCB(skb)->flags = 0;
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skb->protocol = htons(ETH_P_IPV6);
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skb->pkt_type = PACKET_HOST;
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if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
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!isatap_srcok(skb, iph, tunnel->dev)) {
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tunnel->stat.rx_errors++;
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read_unlock(&ipip6_lock);
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kfree_skb(skb);
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return 0;
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}
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tunnel->stat.rx_packets++;
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tunnel->stat.rx_bytes += skb->len;
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skb->dev = tunnel->dev;
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dst_release(skb->dst);
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skb->dst = NULL;
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nf_reset(skb);
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ipip6_ecn_decapsulate(iph, skb);
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netif_rx(skb);
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read_unlock(&ipip6_lock);
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return 0;
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}
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icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
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kfree_skb(skb);
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read_unlock(&ipip6_lock);
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out:
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return 0;
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}
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/* Returns the embedded IPv4 address if the IPv6 address
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comes from 6to4 (RFC 3056) addr space */
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static inline __be32 try_6to4(struct in6_addr *v6dst)
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{
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__be32 dst = 0;
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if (v6dst->s6_addr16[0] == htons(0x2002)) {
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/* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
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memcpy(&dst, &v6dst->s6_addr16[1], 4);
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}
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return dst;
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}
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/*
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* This function assumes it is being called from dev_queue_xmit()
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* and that skb is filled properly by that function.
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*/
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static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
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{
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struct ip_tunnel *tunnel = netdev_priv(dev);
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struct net_device_stats *stats = &tunnel->stat;
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struct iphdr *tiph = &tunnel->parms.iph;
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struct ipv6hdr *iph6 = ipv6_hdr(skb);
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u8 tos = tunnel->parms.iph.tos;
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struct rtable *rt; /* Route to the other host */
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struct net_device *tdev; /* Device to other host */
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struct iphdr *iph; /* Our new IP header */
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unsigned int max_headroom; /* The extra header space needed */
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__be32 dst = tiph->daddr;
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int mtu;
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struct in6_addr *addr6;
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int addr_type;
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if (tunnel->recursion++) {
|
|
tunnel->stat.collisions++;
|
|
goto tx_error;
|
|
}
|
|
|
|
if (skb->protocol != htons(ETH_P_IPV6))
|
|
goto tx_error;
|
|
|
|
/* ISATAP (RFC4214) - must come before 6to4 */
|
|
if (dev->priv_flags & IFF_ISATAP) {
|
|
struct neighbour *neigh = NULL;
|
|
|
|
if (skb->dst)
|
|
neigh = skb->dst->neighbour;
|
|
|
|
if (neigh == NULL) {
|
|
if (net_ratelimit())
|
|
printk(KERN_DEBUG "sit: nexthop == NULL\n");
|
|
goto tx_error;
|
|
}
|
|
|
|
addr6 = (struct in6_addr*)&neigh->primary_key;
|
|
addr_type = ipv6_addr_type(addr6);
|
|
|
|
if ((addr_type & IPV6_ADDR_UNICAST) &&
|
|
ipv6_addr_is_isatap(addr6))
|
|
dst = addr6->s6_addr32[3];
|
|
else
|
|
goto tx_error;
|
|
}
|
|
|
|
if (!dst)
|
|
dst = try_6to4(&iph6->daddr);
|
|
|
|
if (!dst) {
|
|
struct neighbour *neigh = NULL;
|
|
|
|
if (skb->dst)
|
|
neigh = skb->dst->neighbour;
|
|
|
|
if (neigh == NULL) {
|
|
if (net_ratelimit())
|
|
printk(KERN_DEBUG "sit: nexthop == NULL\n");
|
|
goto tx_error;
|
|
}
|
|
|
|
addr6 = (struct in6_addr*)&neigh->primary_key;
|
|
addr_type = ipv6_addr_type(addr6);
|
|
|
|
if (addr_type == IPV6_ADDR_ANY) {
|
|
addr6 = &ipv6_hdr(skb)->daddr;
|
|
addr_type = ipv6_addr_type(addr6);
|
|
}
|
|
|
|
if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
|
|
goto tx_error_icmp;
|
|
|
|
dst = addr6->s6_addr32[3];
|
|
}
|
|
|
|
{
|
|
struct flowi fl = { .nl_u = { .ip4_u =
|
|
{ .daddr = dst,
|
|
.saddr = tiph->saddr,
|
|
.tos = RT_TOS(tos) } },
|
|
.oif = tunnel->parms.link,
|
|
.proto = IPPROTO_IPV6 };
|
|
if (ip_route_output_key(&init_net, &rt, &fl)) {
|
|
tunnel->stat.tx_carrier_errors++;
|
|
goto tx_error_icmp;
|
|
}
|
|
}
|
|
if (rt->rt_type != RTN_UNICAST) {
|
|
ip_rt_put(rt);
|
|
tunnel->stat.tx_carrier_errors++;
|
|
goto tx_error_icmp;
|
|
}
|
|
tdev = rt->u.dst.dev;
|
|
|
|
if (tdev == dev) {
|
|
ip_rt_put(rt);
|
|
tunnel->stat.collisions++;
|
|
goto tx_error;
|
|
}
|
|
|
|
if (tiph->frag_off)
|
|
mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
|
|
else
|
|
mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
|
|
|
|
if (mtu < 68) {
|
|
tunnel->stat.collisions++;
|
|
ip_rt_put(rt);
|
|
goto tx_error;
|
|
}
|
|
if (mtu < IPV6_MIN_MTU)
|
|
mtu = IPV6_MIN_MTU;
|
|
if (tunnel->parms.iph.daddr && skb->dst)
|
|
skb->dst->ops->update_pmtu(skb->dst, mtu);
|
|
|
|
if (skb->len > mtu) {
|
|
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
|
|
ip_rt_put(rt);
|
|
goto tx_error;
|
|
}
|
|
|
|
if (tunnel->err_count > 0) {
|
|
if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
|
|
tunnel->err_count--;
|
|
dst_link_failure(skb);
|
|
} else
|
|
tunnel->err_count = 0;
|
|
}
|
|
|
|
/*
|
|
* Okay, now see if we can stuff it in the buffer as-is.
|
|
*/
|
|
max_headroom = LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr);
|
|
|
|
if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
|
|
(skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
|
|
struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
|
|
if (!new_skb) {
|
|
ip_rt_put(rt);
|
|
stats->tx_dropped++;
|
|
dev_kfree_skb(skb);
|
|
tunnel->recursion--;
|
|
return 0;
|
|
}
|
|
if (skb->sk)
|
|
skb_set_owner_w(new_skb, skb->sk);
|
|
dev_kfree_skb(skb);
|
|
skb = new_skb;
|
|
iph6 = ipv6_hdr(skb);
|
|
}
|
|
|
|
skb->transport_header = skb->network_header;
|
|
skb_push(skb, sizeof(struct iphdr));
|
|
skb_reset_network_header(skb);
|
|
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
|
|
IPCB(skb)->flags = 0;
|
|
dst_release(skb->dst);
|
|
skb->dst = &rt->u.dst;
|
|
|
|
/*
|
|
* Push down and install the IPIP header.
|
|
*/
|
|
|
|
iph = ip_hdr(skb);
|
|
iph->version = 4;
|
|
iph->ihl = sizeof(struct iphdr)>>2;
|
|
if (mtu > IPV6_MIN_MTU)
|
|
iph->frag_off = htons(IP_DF);
|
|
else
|
|
iph->frag_off = 0;
|
|
|
|
iph->protocol = IPPROTO_IPV6;
|
|
iph->tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
|
|
iph->daddr = rt->rt_dst;
|
|
iph->saddr = rt->rt_src;
|
|
|
|
if ((iph->ttl = tiph->ttl) == 0)
|
|
iph->ttl = iph6->hop_limit;
|
|
|
|
nf_reset(skb);
|
|
|
|
IPTUNNEL_XMIT();
|
|
tunnel->recursion--;
|
|
return 0;
|
|
|
|
tx_error_icmp:
|
|
dst_link_failure(skb);
|
|
tx_error:
|
|
stats->tx_errors++;
|
|
dev_kfree_skb(skb);
|
|
tunnel->recursion--;
|
|
return 0;
|
|
}
|
|
|
|
static void ipip6_tunnel_bind_dev(struct net_device *dev)
|
|
{
|
|
struct net_device *tdev = NULL;
|
|
struct ip_tunnel *tunnel;
|
|
struct iphdr *iph;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
iph = &tunnel->parms.iph;
|
|
|
|
if (iph->daddr) {
|
|
struct flowi fl = { .nl_u = { .ip4_u =
|
|
{ .daddr = iph->daddr,
|
|
.saddr = iph->saddr,
|
|
.tos = RT_TOS(iph->tos) } },
|
|
.oif = tunnel->parms.link,
|
|
.proto = IPPROTO_IPV6 };
|
|
struct rtable *rt;
|
|
if (!ip_route_output_key(&init_net, &rt, &fl)) {
|
|
tdev = rt->u.dst.dev;
|
|
ip_rt_put(rt);
|
|
}
|
|
dev->flags |= IFF_POINTOPOINT;
|
|
}
|
|
|
|
if (!tdev && tunnel->parms.link)
|
|
tdev = __dev_get_by_index(&init_net, tunnel->parms.link);
|
|
|
|
if (tdev) {
|
|
dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
|
|
dev->mtu = tdev->mtu - sizeof(struct iphdr);
|
|
if (dev->mtu < IPV6_MIN_MTU)
|
|
dev->mtu = IPV6_MIN_MTU;
|
|
}
|
|
dev->iflink = tunnel->parms.link;
|
|
}
|
|
|
|
static int
|
|
ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
|
|
{
|
|
int err = 0;
|
|
struct ip_tunnel_parm p;
|
|
struct ip_tunnel *t;
|
|
|
|
switch (cmd) {
|
|
case SIOCGETTUNNEL:
|
|
t = NULL;
|
|
if (dev == ipip6_fb_tunnel_dev) {
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
|
|
err = -EFAULT;
|
|
break;
|
|
}
|
|
t = ipip6_tunnel_locate(&p, 0);
|
|
}
|
|
if (t == NULL)
|
|
t = netdev_priv(dev);
|
|
memcpy(&p, &t->parms, sizeof(p));
|
|
if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
|
|
err = -EFAULT;
|
|
break;
|
|
|
|
case SIOCADDTUNNEL:
|
|
case SIOCCHGTUNNEL:
|
|
err = -EPERM;
|
|
if (!capable(CAP_NET_ADMIN))
|
|
goto done;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
|
|
goto done;
|
|
|
|
err = -EINVAL;
|
|
if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPV6 ||
|
|
p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
|
|
goto done;
|
|
if (p.iph.ttl)
|
|
p.iph.frag_off |= htons(IP_DF);
|
|
|
|
t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL);
|
|
|
|
if (dev != ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
|
|
if (t != NULL) {
|
|
if (t->dev != dev) {
|
|
err = -EEXIST;
|
|
break;
|
|
}
|
|
} else {
|
|
if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
|
|
(!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
t = netdev_priv(dev);
|
|
ipip6_tunnel_unlink(t);
|
|
t->parms.iph.saddr = p.iph.saddr;
|
|
t->parms.iph.daddr = p.iph.daddr;
|
|
memcpy(dev->dev_addr, &p.iph.saddr, 4);
|
|
memcpy(dev->broadcast, &p.iph.daddr, 4);
|
|
ipip6_tunnel_link(t);
|
|
netdev_state_change(dev);
|
|
}
|
|
}
|
|
|
|
if (t) {
|
|
err = 0;
|
|
if (cmd == SIOCCHGTUNNEL) {
|
|
t->parms.iph.ttl = p.iph.ttl;
|
|
t->parms.iph.tos = p.iph.tos;
|
|
if (t->parms.link != p.link) {
|
|
t->parms.link = p.link;
|
|
ipip6_tunnel_bind_dev(dev);
|
|
netdev_state_change(dev);
|
|
}
|
|
}
|
|
if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
|
|
err = -EFAULT;
|
|
} else
|
|
err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
|
|
break;
|
|
|
|
case SIOCDELTUNNEL:
|
|
err = -EPERM;
|
|
if (!capable(CAP_NET_ADMIN))
|
|
goto done;
|
|
|
|
if (dev == ipip6_fb_tunnel_dev) {
|
|
err = -EFAULT;
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
|
|
goto done;
|
|
err = -ENOENT;
|
|
if ((t = ipip6_tunnel_locate(&p, 0)) == NULL)
|
|
goto done;
|
|
err = -EPERM;
|
|
if (t == netdev_priv(ipip6_fb_tunnel_dev))
|
|
goto done;
|
|
dev = t->dev;
|
|
}
|
|
unregister_netdevice(dev);
|
|
err = 0;
|
|
break;
|
|
|
|
default:
|
|
err = -EINVAL;
|
|
}
|
|
|
|
done:
|
|
return err;
|
|
}
|
|
|
|
static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
|
|
{
|
|
return &(((struct ip_tunnel*)netdev_priv(dev))->stat);
|
|
}
|
|
|
|
static int ipip6_tunnel_change_mtu(struct net_device *dev, int new_mtu)
|
|
{
|
|
if (new_mtu < IPV6_MIN_MTU || new_mtu > 0xFFF8 - sizeof(struct iphdr))
|
|
return -EINVAL;
|
|
dev->mtu = new_mtu;
|
|
return 0;
|
|
}
|
|
|
|
static void ipip6_tunnel_setup(struct net_device *dev)
|
|
{
|
|
dev->uninit = ipip6_tunnel_uninit;
|
|
dev->destructor = free_netdev;
|
|
dev->hard_start_xmit = ipip6_tunnel_xmit;
|
|
dev->get_stats = ipip6_tunnel_get_stats;
|
|
dev->do_ioctl = ipip6_tunnel_ioctl;
|
|
dev->change_mtu = ipip6_tunnel_change_mtu;
|
|
|
|
dev->type = ARPHRD_SIT;
|
|
dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
|
|
dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
|
|
dev->flags = IFF_NOARP;
|
|
dev->iflink = 0;
|
|
dev->addr_len = 4;
|
|
}
|
|
|
|
static int ipip6_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
|
|
tunnel->dev = dev;
|
|
strcpy(tunnel->parms.name, dev->name);
|
|
|
|
memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
|
|
memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
|
|
|
|
ipip6_tunnel_bind_dev(dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init ipip6_fb_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct iphdr *iph = &tunnel->parms.iph;
|
|
|
|
tunnel->dev = dev;
|
|
strcpy(tunnel->parms.name, dev->name);
|
|
|
|
iph->version = 4;
|
|
iph->protocol = IPPROTO_IPV6;
|
|
iph->ihl = 5;
|
|
iph->ttl = 64;
|
|
|
|
dev_hold(dev);
|
|
tunnels_wc[0] = tunnel;
|
|
return 0;
|
|
}
|
|
|
|
static struct xfrm_tunnel sit_handler = {
|
|
.handler = ipip6_rcv,
|
|
.err_handler = ipip6_err,
|
|
.priority = 1,
|
|
};
|
|
|
|
static void __exit sit_destroy_tunnels(void)
|
|
{
|
|
int prio;
|
|
|
|
for (prio = 1; prio < 4; prio++) {
|
|
int h;
|
|
for (h = 0; h < HASH_SIZE; h++) {
|
|
struct ip_tunnel *t;
|
|
while ((t = tunnels[prio][h]) != NULL)
|
|
unregister_netdevice(t->dev);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void __exit sit_cleanup(void)
|
|
{
|
|
xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
|
|
|
|
rtnl_lock();
|
|
sit_destroy_tunnels();
|
|
unregister_netdevice(ipip6_fb_tunnel_dev);
|
|
rtnl_unlock();
|
|
}
|
|
|
|
static int __init sit_init(void)
|
|
{
|
|
int err;
|
|
|
|
printk(KERN_INFO "IPv6 over IPv4 tunneling driver\n");
|
|
|
|
if (xfrm4_tunnel_register(&sit_handler, AF_INET6) < 0) {
|
|
printk(KERN_INFO "sit init: Can't add protocol\n");
|
|
return -EAGAIN;
|
|
}
|
|
|
|
ipip6_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
|
|
ipip6_tunnel_setup);
|
|
if (!ipip6_fb_tunnel_dev) {
|
|
err = -ENOMEM;
|
|
goto err1;
|
|
}
|
|
|
|
ipip6_fb_tunnel_dev->init = ipip6_fb_tunnel_init;
|
|
|
|
if ((err = register_netdev(ipip6_fb_tunnel_dev)))
|
|
goto err2;
|
|
|
|
out:
|
|
return err;
|
|
err2:
|
|
free_netdev(ipip6_fb_tunnel_dev);
|
|
err1:
|
|
xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
|
|
goto out;
|
|
}
|
|
|
|
module_init(sit_init);
|
|
module_exit(sit_cleanup);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("sit0");
|