mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-29 20:30:35 +00:00
1094 lines
24 KiB
C
1094 lines
24 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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* 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 Templin <fred.l.templin@boeing.com>: 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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#include <net/net_namespace.h>
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#include <net/netns/generic.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 void ipip6_fb_tunnel_init(struct net_device *dev);
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static void 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 int sit_net_id;
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struct sit_net {
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struct ip_tunnel *tunnels_r_l[HASH_SIZE];
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struct ip_tunnel *tunnels_r[HASH_SIZE];
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struct ip_tunnel *tunnels_l[HASH_SIZE];
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struct ip_tunnel *tunnels_wc[1];
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struct ip_tunnel **tunnels[4];
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struct net_device *fb_tunnel_dev;
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};
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static DEFINE_RWLOCK(ipip6_lock);
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static struct ip_tunnel * ipip6_tunnel_lookup(struct net *net,
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__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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struct sit_net *sitn = net_generic(net, sit_net_id);
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for (t = sitn->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 = sitn->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 = sitn->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 = sitn->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 sit_net *sitn,
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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 &sitn->tunnels[prio][h];
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}
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static inline struct ip_tunnel **ipip6_bucket(struct sit_net *sitn,
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struct ip_tunnel *t)
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{
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return __ipip6_bucket(sitn, &t->parms);
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}
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static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
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{
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struct ip_tunnel **tp;
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for (tp = ipip6_bucket(sitn, 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 sit_net *sitn, struct ip_tunnel *t)
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{
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struct ip_tunnel **tp = ipip6_bucket(sitn, 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 net *net,
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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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struct sit_net *sitn = net_generic(net, sit_net_id);
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for (tp = __ipip6_bucket(sitn, 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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sprintf(name, "sit%%d");
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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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dev_net_set(dev, net);
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if (strchr(name, '%')) {
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if (dev_alloc_name(dev, name) < 0)
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goto failed_free;
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}
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nt = netdev_priv(dev);
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nt->parms = *parms;
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ipip6_tunnel_init(dev);
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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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goto failed_free;
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dev_hold(dev);
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ipip6_tunnel_link(sitn, nt);
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return nt;
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failed_free:
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free_netdev(dev);
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failed:
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return NULL;
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}
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static struct ip_tunnel_prl_entry *
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__ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
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{
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struct ip_tunnel_prl_entry *p = (struct ip_tunnel_prl_entry *)NULL;
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for (p = t->prl; p; p = p->next)
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if (p->addr == addr)
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break;
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return p;
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}
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static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
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struct ip_tunnel_prl __user *a)
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{
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struct ip_tunnel_prl kprl, *kp;
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struct ip_tunnel_prl_entry *prl;
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unsigned int cmax, c = 0, ca, len;
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int ret = 0;
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if (copy_from_user(&kprl, a, sizeof(kprl)))
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return -EFAULT;
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cmax = kprl.datalen / sizeof(kprl);
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if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
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cmax = 1;
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/* For simple GET or for root users,
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* we try harder to allocate.
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*/
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kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
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kcalloc(cmax, sizeof(*kp), GFP_KERNEL) :
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NULL;
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read_lock(&ipip6_lock);
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ca = t->prl_count < cmax ? t->prl_count : cmax;
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if (!kp) {
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/* We don't try hard to allocate much memory for
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* non-root users.
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* For root users, retry allocating enough memory for
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* the answer.
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*/
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kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
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if (!kp) {
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ret = -ENOMEM;
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goto out;
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}
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}
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c = 0;
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for (prl = t->prl; prl; prl = prl->next) {
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if (c > cmax)
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break;
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if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
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continue;
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kp[c].addr = prl->addr;
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kp[c].flags = prl->flags;
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c++;
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if (kprl.addr != htonl(INADDR_ANY))
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break;
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}
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out:
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read_unlock(&ipip6_lock);
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len = sizeof(*kp) * c;
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ret = 0;
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if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
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ret = -EFAULT;
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kfree(kp);
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return ret;
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}
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static int
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ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
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{
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struct ip_tunnel_prl_entry *p;
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int err = 0;
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if (a->addr == htonl(INADDR_ANY))
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return -EINVAL;
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write_lock(&ipip6_lock);
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for (p = t->prl; p; p = p->next) {
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if (p->addr == a->addr) {
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if (chg)
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goto update;
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err = -EEXIST;
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goto out;
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}
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}
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if (chg) {
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err = -ENXIO;
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goto out;
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}
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p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
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if (!p) {
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err = -ENOBUFS;
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goto out;
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}
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p->next = t->prl;
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t->prl = p;
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t->prl_count++;
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update:
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p->addr = a->addr;
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p->flags = a->flags;
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out:
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write_unlock(&ipip6_lock);
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return err;
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}
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static int
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ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
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{
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struct ip_tunnel_prl_entry *x, **p;
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int err = 0;
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write_lock(&ipip6_lock);
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if (a && a->addr != htonl(INADDR_ANY)) {
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for (p = &t->prl; *p; p = &(*p)->next) {
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if ((*p)->addr == a->addr) {
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x = *p;
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*p = x->next;
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kfree(x);
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t->prl_count--;
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goto out;
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}
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}
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err = -ENXIO;
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} else {
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while (t->prl) {
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x = t->prl;
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t->prl = t->prl->next;
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kfree(x);
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t->prl_count--;
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}
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}
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out:
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write_unlock(&ipip6_lock);
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return 0;
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}
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static int
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isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t)
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{
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struct ip_tunnel_prl_entry *p;
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int ok = 1;
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read_lock(&ipip6_lock);
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p = __ipip6_tunnel_locate_prl(t, iph->saddr);
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if (p) {
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if (p->flags & PRL_DEFAULT)
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skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
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else
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skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
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} else {
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struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
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if (ipv6_addr_is_isatap(addr6) &&
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(addr6->s6_addr32[3] == iph->saddr) &&
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ipv6_chk_prefix(addr6, t->dev))
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skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
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else
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ok = 0;
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}
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read_unlock(&ipip6_lock);
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return ok;
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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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struct net *net = dev_net(dev);
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struct sit_net *sitn = net_generic(net, sit_net_id);
|
|
|
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if (dev == sitn->fb_tunnel_dev) {
|
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write_lock_bh(&ipip6_lock);
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sitn->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(sitn, netdev_priv(dev));
|
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ipip6_tunnel_del_prl(netdev_priv(dev), NULL);
|
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dev_put(dev);
|
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}
|
|
}
|
|
|
|
|
|
static int ipip6_err(struct sk_buff *skb, u32 info)
|
|
{
|
|
|
|
/* All the routers (except for Linux) return only
|
|
8 bytes of packet payload. It means, that precise relaying of
|
|
ICMP in the real Internet is absolutely infeasible.
|
|
*/
|
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struct iphdr *iph = (struct iphdr*)skb->data;
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const int type = icmp_hdr(skb)->type;
|
|
const int code = icmp_hdr(skb)->code;
|
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struct ip_tunnel *t;
|
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int err;
|
|
|
|
switch (type) {
|
|
default:
|
|
case ICMP_PARAMETERPROB:
|
|
return 0;
|
|
|
|
case ICMP_DEST_UNREACH:
|
|
switch (code) {
|
|
case ICMP_SR_FAILED:
|
|
case ICMP_PORT_UNREACH:
|
|
/* Impossible event. */
|
|
return 0;
|
|
case ICMP_FRAG_NEEDED:
|
|
/* Soft state for pmtu is maintained by IP core. */
|
|
return 0;
|
|
default:
|
|
/* All others are translated to HOST_UNREACH.
|
|
rfc2003 contains "deep thoughts" about NET_UNREACH,
|
|
I believe they are just ether pollution. --ANK
|
|
*/
|
|
break;
|
|
}
|
|
break;
|
|
case ICMP_TIME_EXCEEDED:
|
|
if (code != ICMP_EXC_TTL)
|
|
return 0;
|
|
break;
|
|
}
|
|
|
|
err = -ENOENT;
|
|
|
|
read_lock(&ipip6_lock);
|
|
t = ipip6_tunnel_lookup(dev_net(skb->dev), iph->daddr, iph->saddr);
|
|
if (t == NULL || t->parms.iph.daddr == 0)
|
|
goto out;
|
|
|
|
err = 0;
|
|
if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
|
|
goto out;
|
|
|
|
if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
|
|
t->err_count++;
|
|
else
|
|
t->err_count = 1;
|
|
t->err_time = jiffies;
|
|
out:
|
|
read_unlock(&ipip6_lock);
|
|
return err;
|
|
}
|
|
|
|
static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
|
|
{
|
|
if (INET_ECN_is_ce(iph->tos))
|
|
IP6_ECN_set_ce(ipv6_hdr(skb));
|
|
}
|
|
|
|
static int ipip6_rcv(struct sk_buff *skb)
|
|
{
|
|
struct iphdr *iph;
|
|
struct ip_tunnel *tunnel;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
|
|
goto out;
|
|
|
|
iph = ip_hdr(skb);
|
|
|
|
read_lock(&ipip6_lock);
|
|
if ((tunnel = ipip6_tunnel_lookup(dev_net(skb->dev),
|
|
iph->saddr, iph->daddr)) != NULL) {
|
|
secpath_reset(skb);
|
|
skb->mac_header = skb->network_header;
|
|
skb_reset_network_header(skb);
|
|
IPCB(skb)->flags = 0;
|
|
skb->protocol = htons(ETH_P_IPV6);
|
|
skb->pkt_type = PACKET_HOST;
|
|
|
|
if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
|
|
!isatap_chksrc(skb, iph, tunnel)) {
|
|
tunnel->dev->stats.rx_errors++;
|
|
read_unlock(&ipip6_lock);
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
tunnel->dev->stats.rx_packets++;
|
|
tunnel->dev->stats.rx_bytes += skb->len;
|
|
skb->dev = tunnel->dev;
|
|
dst_release(skb->dst);
|
|
skb->dst = NULL;
|
|
nf_reset(skb);
|
|
ipip6_ecn_decapsulate(iph, skb);
|
|
netif_rx(skb);
|
|
read_unlock(&ipip6_lock);
|
|
return 0;
|
|
}
|
|
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
|
|
read_unlock(&ipip6_lock);
|
|
out:
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
/* Returns the embedded IPv4 address if the IPv6 address
|
|
comes from 6to4 (RFC 3056) addr space */
|
|
|
|
static inline __be32 try_6to4(struct in6_addr *v6dst)
|
|
{
|
|
__be32 dst = 0;
|
|
|
|
if (v6dst->s6_addr16[0] == htons(0x2002)) {
|
|
/* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
|
|
memcpy(&dst, &v6dst->s6_addr16[1], 4);
|
|
}
|
|
return dst;
|
|
}
|
|
|
|
/*
|
|
* This function assumes it is being called from dev_queue_xmit()
|
|
* and that skb is filled properly by that function.
|
|
*/
|
|
|
|
static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct net_device_stats *stats = &tunnel->dev->stats;
|
|
struct iphdr *tiph = &tunnel->parms.iph;
|
|
struct ipv6hdr *iph6 = ipv6_hdr(skb);
|
|
u8 tos = tunnel->parms.iph.tos;
|
|
struct rtable *rt; /* Route to the other host */
|
|
struct net_device *tdev; /* Device to other host */
|
|
struct iphdr *iph; /* Our new IP header */
|
|
unsigned int max_headroom; /* The extra header space needed */
|
|
__be32 dst = tiph->daddr;
|
|
int mtu;
|
|
struct in6_addr *addr6;
|
|
int addr_type;
|
|
|
|
if (tunnel->recursion++) {
|
|
stats->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(dev_net(dev), &rt, &fl)) {
|
|
stats->tx_carrier_errors++;
|
|
goto tx_error_icmp;
|
|
}
|
|
}
|
|
if (rt->rt_type != RTN_UNICAST) {
|
|
ip_rt_put(rt);
|
|
stats->tx_carrier_errors++;
|
|
goto tx_error_icmp;
|
|
}
|
|
tdev = rt->u.dst.dev;
|
|
|
|
if (tdev == dev) {
|
|
ip_rt_put(rt);
|
|
stats->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) {
|
|
stats->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 (time_before(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(dev_net(dev), &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(dev_net(dev), 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_prl prl;
|
|
struct ip_tunnel *t;
|
|
struct net *net = dev_net(dev);
|
|
struct sit_net *sitn = net_generic(net, sit_net_id);
|
|
|
|
switch (cmd) {
|
|
case SIOCGETTUNNEL:
|
|
t = NULL;
|
|
if (dev == sitn->fb_tunnel_dev) {
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
|
|
err = -EFAULT;
|
|
break;
|
|
}
|
|
t = ipip6_tunnel_locate(net, &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(net, &p, cmd == SIOCADDTUNNEL);
|
|
|
|
if (dev != sitn->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(sitn, 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(sitn, 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 == sitn->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(net, &p, 0)) == NULL)
|
|
goto done;
|
|
err = -EPERM;
|
|
if (t == netdev_priv(sitn->fb_tunnel_dev))
|
|
goto done;
|
|
dev = t->dev;
|
|
}
|
|
unregister_netdevice(dev);
|
|
err = 0;
|
|
break;
|
|
|
|
case SIOCGETPRL:
|
|
err = -EINVAL;
|
|
if (dev == sitn->fb_tunnel_dev)
|
|
goto done;
|
|
err = -ENOENT;
|
|
if (!(t = netdev_priv(dev)))
|
|
goto done;
|
|
err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
|
|
break;
|
|
|
|
case SIOCADDPRL:
|
|
case SIOCDELPRL:
|
|
case SIOCCHGPRL:
|
|
err = -EPERM;
|
|
if (!capable(CAP_NET_ADMIN))
|
|
goto done;
|
|
err = -EINVAL;
|
|
if (dev == sitn->fb_tunnel_dev)
|
|
goto done;
|
|
err = -EFAULT;
|
|
if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
|
|
goto done;
|
|
err = -ENOENT;
|
|
if (!(t = netdev_priv(dev)))
|
|
goto done;
|
|
|
|
switch (cmd) {
|
|
case SIOCDELPRL:
|
|
err = ipip6_tunnel_del_prl(t, &prl);
|
|
break;
|
|
case SIOCADDPRL:
|
|
case SIOCCHGPRL:
|
|
err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
|
|
break;
|
|
}
|
|
netdev_state_change(dev);
|
|
break;
|
|
|
|
default:
|
|
err = -EINVAL;
|
|
}
|
|
|
|
done:
|
|
return err;
|
|
}
|
|
|
|
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 const struct net_device_ops ipip6_netdev_ops = {
|
|
.ndo_uninit = ipip6_tunnel_uninit,
|
|
.ndo_start_xmit = ipip6_tunnel_xmit,
|
|
.ndo_do_ioctl = ipip6_tunnel_ioctl,
|
|
.ndo_change_mtu = ipip6_tunnel_change_mtu,
|
|
};
|
|
|
|
static void ipip6_tunnel_setup(struct net_device *dev)
|
|
{
|
|
dev->netdev_ops = &ipip6_netdev_ops;
|
|
dev->destructor = free_netdev;
|
|
|
|
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;
|
|
dev->features |= NETIF_F_NETNS_LOCAL;
|
|
}
|
|
|
|
static void ipip6_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_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);
|
|
}
|
|
|
|
static void ipip6_fb_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct iphdr *iph = &tunnel->parms.iph;
|
|
struct net *net = dev_net(dev);
|
|
struct sit_net *sitn = net_generic(net, sit_net_id);
|
|
|
|
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);
|
|
sitn->tunnels_wc[0] = tunnel;
|
|
}
|
|
|
|
static struct xfrm_tunnel sit_handler = {
|
|
.handler = ipip6_rcv,
|
|
.err_handler = ipip6_err,
|
|
.priority = 1,
|
|
};
|
|
|
|
static void sit_destroy_tunnels(struct sit_net *sitn)
|
|
{
|
|
int prio;
|
|
|
|
for (prio = 1; prio < 4; prio++) {
|
|
int h;
|
|
for (h = 0; h < HASH_SIZE; h++) {
|
|
struct ip_tunnel *t;
|
|
while ((t = sitn->tunnels[prio][h]) != NULL)
|
|
unregister_netdevice(t->dev);
|
|
}
|
|
}
|
|
}
|
|
|
|
static int sit_init_net(struct net *net)
|
|
{
|
|
int err;
|
|
struct sit_net *sitn;
|
|
|
|
err = -ENOMEM;
|
|
sitn = kzalloc(sizeof(struct sit_net), GFP_KERNEL);
|
|
if (sitn == NULL)
|
|
goto err_alloc;
|
|
|
|
err = net_assign_generic(net, sit_net_id, sitn);
|
|
if (err < 0)
|
|
goto err_assign;
|
|
|
|
sitn->tunnels[0] = sitn->tunnels_wc;
|
|
sitn->tunnels[1] = sitn->tunnels_l;
|
|
sitn->tunnels[2] = sitn->tunnels_r;
|
|
sitn->tunnels[3] = sitn->tunnels_r_l;
|
|
|
|
sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
|
|
ipip6_tunnel_setup);
|
|
if (!sitn->fb_tunnel_dev) {
|
|
err = -ENOMEM;
|
|
goto err_alloc_dev;
|
|
}
|
|
dev_net_set(sitn->fb_tunnel_dev, net);
|
|
|
|
ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
|
|
|
|
if ((err = register_netdev(sitn->fb_tunnel_dev)))
|
|
goto err_reg_dev;
|
|
|
|
return 0;
|
|
|
|
err_reg_dev:
|
|
dev_put(sitn->fb_tunnel_dev);
|
|
free_netdev(sitn->fb_tunnel_dev);
|
|
err_alloc_dev:
|
|
/* nothing */
|
|
err_assign:
|
|
kfree(sitn);
|
|
err_alloc:
|
|
return err;
|
|
}
|
|
|
|
static void sit_exit_net(struct net *net)
|
|
{
|
|
struct sit_net *sitn;
|
|
|
|
sitn = net_generic(net, sit_net_id);
|
|
rtnl_lock();
|
|
sit_destroy_tunnels(sitn);
|
|
unregister_netdevice(sitn->fb_tunnel_dev);
|
|
rtnl_unlock();
|
|
kfree(sitn);
|
|
}
|
|
|
|
static struct pernet_operations sit_net_ops = {
|
|
.init = sit_init_net,
|
|
.exit = sit_exit_net,
|
|
};
|
|
|
|
static void __exit sit_cleanup(void)
|
|
{
|
|
xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
|
|
|
|
unregister_pernet_gen_device(sit_net_id, &sit_net_ops);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
err = register_pernet_gen_device(&sit_net_id, &sit_net_ops);
|
|
if (err < 0)
|
|
xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
|
|
|
|
return err;
|
|
}
|
|
|
|
module_init(sit_init);
|
|
module_exit(sit_cleanup);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("sit0");
|