sit.c
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上传日期:2013-02-24
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文件大小:19k
- /*
- * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
- * Linux INET6 implementation
- *
- * Authors:
- * Pedro Roque <roque@di.fc.ul.pt>
- * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
- *
- * $Id: sit.c,v 1.53 2001/09/25 05:09:53 davem Exp $
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- *
- * Changes:
- * Roger Venning <r.venning@telstra.com>: 6to4 support
- * Nate Thompson <nate@thebog.net>: 6to4 support
- */
- #define __NO_VERSION__
- #include <linux/config.h>
- #include <linux/module.h>
- #include <linux/errno.h>
- #include <linux/types.h>
- #include <linux/socket.h>
- #include <linux/sockios.h>
- #include <linux/sched.h>
- #include <linux/net.h>
- #include <linux/in6.h>
- #include <linux/netdevice.h>
- #include <linux/if_arp.h>
- #include <linux/icmp.h>
- #include <asm/uaccess.h>
- #include <linux/init.h>
- #include <linux/netfilter_ipv4.h>
- #include <net/sock.h>
- #include <net/snmp.h>
- #include <net/ipv6.h>
- #include <net/protocol.h>
- #include <net/transp_v6.h>
- #include <net/ip6_fib.h>
- #include <net/ip6_route.h>
- #include <net/ndisc.h>
- #include <net/addrconf.h>
- #include <net/ip.h>
- #include <net/udp.h>
- #include <net/icmp.h>
- #include <net/ipip.h>
- #include <net/inet_ecn.h>
- /*
- This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
- For comments look at net/ipv4/ip_gre.c --ANK
- */
- #define HASH_SIZE 16
- #define HASH(addr) ((addr^(addr>>4))&0xF)
- static int ipip6_fb_tunnel_init(struct net_device *dev);
- static int ipip6_tunnel_init(struct net_device *dev);
- static struct net_device ipip6_fb_tunnel_dev = {
- "sit0", 0x0, 0x0, 0x0, 0x0, 0, 0, 0, 0, 0, NULL, ipip6_fb_tunnel_init,
- };
- static struct ip_tunnel ipip6_fb_tunnel = {
- NULL, &ipip6_fb_tunnel_dev, {0, }, 0, 0, 0, 0, 0, 0, 0, {"sit0", }
- };
- static struct ip_tunnel *tunnels_r_l[HASH_SIZE];
- static struct ip_tunnel *tunnels_r[HASH_SIZE];
- static struct ip_tunnel *tunnels_l[HASH_SIZE];
- static struct ip_tunnel *tunnels_wc[1];
- static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l };
- static rwlock_t ipip6_lock = RW_LOCK_UNLOCKED;
- static struct ip_tunnel * ipip6_tunnel_lookup(u32 remote, u32 local)
- {
- unsigned h0 = HASH(remote);
- unsigned h1 = HASH(local);
- struct ip_tunnel *t;
- for (t = tunnels_r_l[h0^h1]; t; t = t->next) {
- if (local == t->parms.iph.saddr &&
- remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
- return t;
- }
- for (t = tunnels_r[h0]; t; t = t->next) {
- if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
- return t;
- }
- for (t = tunnels_l[h1]; t; t = t->next) {
- if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
- return t;
- }
- if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
- return t;
- return NULL;
- }
- static struct ip_tunnel ** ipip6_bucket(struct ip_tunnel *t)
- {
- u32 remote = t->parms.iph.daddr;
- u32 local = t->parms.iph.saddr;
- unsigned h = 0;
- int prio = 0;
- if (remote) {
- prio |= 2;
- h ^= HASH(remote);
- }
- if (local) {
- prio |= 1;
- h ^= HASH(local);
- }
- return &tunnels[prio][h];
- }
- static void ipip6_tunnel_unlink(struct ip_tunnel *t)
- {
- struct ip_tunnel **tp;
- for (tp = ipip6_bucket(t); *tp; tp = &(*tp)->next) {
- if (t == *tp) {
- write_lock_bh(&ipip6_lock);
- *tp = t->next;
- write_unlock_bh(&ipip6_lock);
- break;
- }
- }
- }
- static void ipip6_tunnel_link(struct ip_tunnel *t)
- {
- struct ip_tunnel **tp = ipip6_bucket(t);
- write_lock_bh(&ipip6_lock);
- t->next = *tp;
- write_unlock_bh(&ipip6_lock);
- *tp = t;
- }
- struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int create)
- {
- u32 remote = parms->iph.daddr;
- u32 local = parms->iph.saddr;
- struct ip_tunnel *t, **tp, *nt;
- struct net_device *dev;
- unsigned h = 0;
- int prio = 0;
- if (remote) {
- prio |= 2;
- h ^= HASH(remote);
- }
- if (local) {
- prio |= 1;
- h ^= HASH(local);
- }
- for (tp = &tunnels[prio][h]; (t = *tp) != NULL; tp = &t->next) {
- if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
- return t;
- }
- if (!create)
- return NULL;
- MOD_INC_USE_COUNT;
- dev = kmalloc(sizeof(*dev) + sizeof(*t), GFP_KERNEL);
- if (dev == NULL) {
- MOD_DEC_USE_COUNT;
- return NULL;
- }
- memset(dev, 0, sizeof(*dev) + sizeof(*t));
- dev->priv = (void*)(dev+1);
- nt = (struct ip_tunnel*)dev->priv;
- nt->dev = dev;
- dev->init = ipip6_tunnel_init;
- dev->features |= NETIF_F_DYNALLOC;
- memcpy(&nt->parms, parms, sizeof(*parms));
- nt->parms.name[IFNAMSIZ-1] = ' ';
- strcpy(dev->name, nt->parms.name);
- if (dev->name[0] == 0) {
- int i;
- for (i=1; i<100; i++) {
- sprintf(dev->name, "sit%d", i);
- if (__dev_get_by_name(dev->name) == NULL)
- break;
- }
- if (i==100)
- goto failed;
- memcpy(nt->parms.name, dev->name, IFNAMSIZ);
- }
- if (register_netdevice(dev) < 0)
- goto failed;
- dev_hold(dev);
- ipip6_tunnel_link(nt);
- /* Do not decrement MOD_USE_COUNT here. */
- return nt;
- failed:
- kfree(dev);
- MOD_DEC_USE_COUNT;
- return NULL;
- }
- static void ipip6_tunnel_destructor(struct net_device *dev)
- {
- if (dev != &ipip6_fb_tunnel_dev) {
- MOD_DEC_USE_COUNT;
- }
- }
- static void ipip6_tunnel_uninit(struct net_device *dev)
- {
- if (dev == &ipip6_fb_tunnel_dev) {
- write_lock_bh(&ipip6_lock);
- tunnels_wc[0] = NULL;
- write_unlock_bh(&ipip6_lock);
- dev_put(dev);
- } else {
- ipip6_tunnel_unlink((struct ip_tunnel*)dev->priv);
- dev_put(dev);
- }
- }
- void ipip6_err(struct sk_buff *skb, u32 info)
- {
- #ifndef I_WISH_WORLD_WERE_PERFECT
- /* It is not :-( 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.
- */
- struct iphdr *iph = (struct iphdr*)skb->data;
- int type = skb->h.icmph->type;
- int code = skb->h.icmph->code;
- struct ip_tunnel *t;
- switch (type) {
- default:
- case ICMP_PARAMETERPROB:
- return;
- case ICMP_DEST_UNREACH:
- switch (code) {
- case ICMP_SR_FAILED:
- case ICMP_PORT_UNREACH:
- /* Impossible event. */
- return;
- case ICMP_FRAG_NEEDED:
- /* Soft state for pmtu is maintained by IP core. */
- return;
- 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;
- break;
- }
- read_lock(&ipip6_lock);
- t = ipip6_tunnel_lookup(iph->daddr, iph->saddr);
- if (t == NULL || t->parms.iph.daddr == 0)
- goto out;
- if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
- goto out;
- if (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;
- #else
- struct iphdr *iph = (struct iphdr*)dp;
- int hlen = iph->ihl<<2;
- struct ipv6hdr *iph6;
- int type = skb->h.icmph->type;
- int code = skb->h.icmph->code;
- int rel_type = 0;
- int rel_code = 0;
- int rel_info = 0;
- struct sk_buff *skb2;
- struct rt6_info *rt6i;
- if (len < hlen + sizeof(struct ipv6hdr))
- return;
- iph6 = (struct ipv6hdr*)(dp + hlen);
- switch (type) {
- default:
- return;
- case ICMP_PARAMETERPROB:
- if (skb->h.icmph->un.gateway < hlen)
- return;
- /* So... This guy found something strange INSIDE encapsulated
- packet. Well, he is fool, but what can we do ?
- */
- rel_type = ICMPV6_PARAMPROB;
- rel_info = skb->h.icmph->un.gateway - hlen;
- break;
- case ICMP_DEST_UNREACH:
- switch (code) {
- case ICMP_SR_FAILED:
- case ICMP_PORT_UNREACH:
- /* Impossible event. */
- return;
- case ICMP_FRAG_NEEDED:
- /* Too complicated case ... */
- return;
- default:
- /* All others are translated to HOST_UNREACH.
- rfc2003 contains "deep thoughts" about NET_UNREACH,
- I believe, it is just ether pollution. --ANK
- */
- rel_type = ICMPV6_DEST_UNREACH;
- rel_code = ICMPV6_ADDR_UNREACH;
- break;
- }
- break;
- case ICMP_TIME_EXCEEDED:
- if (code != ICMP_EXC_TTL)
- return;
- rel_type = ICMPV6_TIME_EXCEED;
- rel_code = ICMPV6_EXC_HOPLIMIT;
- break;
- }
- /* Prepare fake skb to feed it to icmpv6_send */
- skb2 = skb_clone(skb, GFP_ATOMIC);
- if (skb2 == NULL)
- return;
- dst_release(skb2->dst);
- skb2->dst = NULL;
- skb_pull(skb2, skb->data - (u8*)iph6);
- skb2->nh.raw = skb2->data;
- /* Try to guess incoming interface */
- rt6i = rt6_lookup(&iph6->saddr, NULL, NULL, 0);
- if (rt6i && rt6i->rt6i_dev) {
- skb2->dev = rt6i->rt6i_dev;
- rt6i = rt6_lookup(&iph6->daddr, &iph6->saddr, NULL, 0);
- if (rt6i && rt6i->rt6i_dev && rt6i->rt6i_dev->type == ARPHRD_SIT) {
- struct ip_tunnel * t = (struct ip_tunnel*)rt6i->rt6i_dev->priv;
- if (rel_type == ICMPV6_TIME_EXCEED && t->parms.iph.ttl) {
- rel_type = ICMPV6_DEST_UNREACH;
- rel_code = ICMPV6_ADDR_UNREACH;
- }
- icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev);
- }
- }
- kfree_skb(skb2);
- return;
- #endif
- }
- static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
- {
- if (INET_ECN_is_ce(iph->tos) &&
- INET_ECN_is_not_ce(ip6_get_dsfield(skb->nh.ipv6h)))
- IP6_ECN_set_ce(skb->nh.ipv6h);
- }
- 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 = skb->nh.iph;
- read_lock(&ipip6_lock);
- if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
- skb->mac.raw = skb->nh.raw;
- skb->nh.raw = skb->data;
- memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
- skb->protocol = __constant_htons(ETH_P_IPV6);
- skb->pkt_type = PACKET_HOST;
- tunnel->stat.rx_packets++;
- tunnel->stat.rx_bytes += skb->len;
- skb->dev = tunnel->dev;
- dst_release(skb->dst);
- skb->dst = NULL;
- #ifdef CONFIG_NETFILTER
- nf_conntrack_put(skb->nfct);
- skb->nfct = NULL;
- #ifdef CONFIG_NETFILTER_DEBUG
- skb->nf_debug = 0;
- #endif
- #endif
- ipip6_ecn_decapsulate(iph, skb);
- netif_rx(skb);
- read_unlock(&ipip6_lock);
- return 0;
- }
- icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PROT_UNREACH, 0);
- kfree_skb(skb);
- read_unlock(&ipip6_lock);
- out:
- return 0;
- }
- /* Need this wrapper because NF_HOOK takes the function address */
- static inline int do_ip_send(struct sk_buff *skb)
- {
- return ip_send(skb);
- }
- /* Returns the embedded IPv4 address if the IPv6 address
- comes from 6to4 (draft-ietf-ngtrans-6to4-04) addr space */
- static inline u32 try_6to4(struct in6_addr *v6dst)
- {
- u32 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 = (struct ip_tunnel*)dev->priv;
- struct net_device_stats *stats = &tunnel->stat;
- struct iphdr *tiph = &tunnel->parms.iph;
- struct ipv6hdr *iph6 = skb->nh.ipv6h;
- 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 */
- int max_headroom; /* The extra header space needed */
- u32 dst = tiph->daddr;
- int mtu;
- struct in6_addr *addr6;
- int addr_type;
- if (tunnel->recursion++) {
- tunnel->stat.collisions++;
- goto tx_error;
- }
- if (skb->protocol != __constant_htons(ETH_P_IPV6))
- 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 == NULLn");
- goto tx_error;
- }
- addr6 = (struct in6_addr*)&neigh->primary_key;
- addr_type = ipv6_addr_type(addr6);
- if (addr_type == IPV6_ADDR_ANY) {
- addr6 = &skb->nh.ipv6h->daddr;
- addr_type = ipv6_addr_type(addr6);
- }
- if ((addr_type & IPV6_ADDR_COMPATv4) == 0)
- goto tx_error_icmp;
- dst = addr6->s6_addr32[3];
- }
- if (ip_route_output(&rt, dst, tiph->saddr, RT_TOS(tos), tunnel->parms.link)) {
- tunnel->stat.tx_carrier_errors++;
- goto tx_error_icmp;
- }
- if (rt->rt_type != RTN_UNICAST) {
- 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;
- }
- mtu = rt->u.dst.pmtu - sizeof(struct iphdr);
- if (mtu < 68) {
- tunnel->stat.collisions++;
- ip_rt_put(rt);
- goto tx_error;
- }
- if (mtu < IPV6_MIN_MTU)
- mtu = IPV6_MIN_MTU;
- if (skb->dst && mtu < skb->dst->pmtu) {
- struct rt6_info *rt6 = (struct rt6_info*)skb->dst;
- if (mtu < rt6->u.dst.pmtu) {
- if (tunnel->parms.iph.daddr || rt6->rt6i_dst.plen == 128) {
- rt6->rt6i_flags |= RTF_MODIFIED;
- rt6->u.dst.pmtu = 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;
- }
- skb->h.raw = skb->nh.raw;
- /*
- * Okay, now see if we can stuff it in the buffer as-is.
- */
- max_headroom = (((tdev->hard_header_len+15)&~15)+sizeof(struct iphdr));
- if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
- 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;
- }
- skb->nh.raw = skb_push(skb, sizeof(struct iphdr));
- memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
- dst_release(skb->dst);
- skb->dst = &rt->u.dst;
- /*
- * Push down and install the IPIP header.
- */
- iph = skb->nh.iph;
- iph->version = 4;
- iph->ihl = sizeof(struct iphdr)>>2;
- if (mtu > IPV6_MIN_MTU)
- iph->frag_off = __constant_htons(IP_DF);
- else
- iph->frag_off = 0;
- iph->protocol = IPPROTO_IPV6;
- iph->tos = INET_ECN_encapsulate(tos, ip6_get_dsfield(iph6));
- iph->daddr = rt->rt_dst;
- iph->saddr = rt->rt_src;
- if ((iph->ttl = tiph->ttl) == 0)
- iph->ttl = iph6->hop_limit;
- #ifdef CONFIG_NETFILTER
- nf_conntrack_put(skb->nfct);
- skb->nfct = NULL;
- #ifdef CONFIG_NETFILTER_DEBUG
- skb->nf_debug = 0;
- #endif
- #endif
- 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 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;
- MOD_INC_USE_COUNT;
- 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 = (struct ip_tunnel*)dev->priv;
- 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&__constant_htons(~IP_DF)))
- goto done;
- if (p.iph.ttl)
- p.iph.frag_off |= __constant_htons(IP_DF);
- t = ipip6_tunnel_locate(&p, cmd == SIOCADDTUNNEL);
- if (dev != &ipip6_fb_tunnel_dev && cmd == SIOCCHGTUNNEL &&
- t != &ipip6_fb_tunnel) {
- 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 = (struct ip_tunnel*)dev->priv;
- 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 (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 == &ipip6_fb_tunnel)
- goto done;
- dev = t->dev;
- }
- err = unregister_netdevice(dev);
- break;
- default:
- err = -EINVAL;
- }
- done:
- MOD_DEC_USE_COUNT;
- return err;
- }
- static struct net_device_stats *ipip6_tunnel_get_stats(struct net_device *dev)
- {
- return &(((struct ip_tunnel*)dev->priv)->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_init_gen(struct net_device *dev)
- {
- struct ip_tunnel *t = (struct ip_tunnel*)dev->priv;
- dev->destructor = ipip6_tunnel_destructor;
- dev->uninit = ipip6_tunnel_uninit;
- 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 = 1500 - sizeof(struct iphdr);
- dev->flags = IFF_NOARP;
- dev->iflink = 0;
- dev->addr_len = 4;
- memcpy(dev->dev_addr, &t->parms.iph.saddr, 4);
- memcpy(dev->broadcast, &t->parms.iph.daddr, 4);
- }
- static int ipip6_tunnel_init(struct net_device *dev)
- {
- struct net_device *tdev = NULL;
- struct ip_tunnel *tunnel;
- struct iphdr *iph;
- tunnel = (struct ip_tunnel*)dev->priv;
- iph = &tunnel->parms.iph;
- ipip6_tunnel_init_gen(dev);
- if (iph->daddr) {
- struct rtable *rt;
- if (!ip_route_output(&rt, iph->daddr, iph->saddr, RT_TOS(iph->tos), tunnel->parms.link)) {
- tdev = rt->u.dst.dev;
- ip_rt_put(rt);
- }
- dev->flags |= IFF_POINTOPOINT;
- }
- if (!tdev && tunnel->parms.link)
- tdev = __dev_get_by_index(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;
- return 0;
- }
- #ifdef MODULE
- static int ipip6_fb_tunnel_open(struct net_device *dev)
- {
- MOD_INC_USE_COUNT;
- return 0;
- }
- static int ipip6_fb_tunnel_close(struct net_device *dev)
- {
- MOD_DEC_USE_COUNT;
- return 0;
- }
- #endif
- int __init ipip6_fb_tunnel_init(struct net_device *dev)
- {
- struct iphdr *iph;
- ipip6_tunnel_init_gen(dev);
- #ifdef MODULE
- dev->open = ipip6_fb_tunnel_open;
- dev->stop = ipip6_fb_tunnel_close;
- #endif
- iph = &ipip6_fb_tunnel.parms.iph;
- iph->version = 4;
- iph->protocol = IPPROTO_IPV6;
- iph->ihl = 5;
- iph->ttl = 64;
- dev_hold(dev);
- tunnels_wc[0] = &ipip6_fb_tunnel;
- return 0;
- }
- static struct inet_protocol sit_protocol = {
- ipip6_rcv,
- ipip6_err,
- 0,
- IPPROTO_IPV6,
- 0,
- NULL,
- "IPv6"
- };
- #ifdef MODULE
- void sit_cleanup(void)
- {
- inet_del_protocol(&sit_protocol);
- unregister_netdev(&ipip6_fb_tunnel_dev);
- }
- #endif
- int __init sit_init(void)
- {
- printk(KERN_INFO "IPv6 over IPv4 tunneling drivern");
- ipip6_fb_tunnel_dev.priv = (void*)&ipip6_fb_tunnel;
- strcpy(ipip6_fb_tunnel_dev.name, ipip6_fb_tunnel.parms.name);
- register_netdev(&ipip6_fb_tunnel_dev);
- inet_add_protocol(&sit_protocol);
- return 0;
- }