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/*
* Linux NET3: IP/IP protocol decoder.
*
* Authors:
* Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
*
* Fixes:
* Alan Cox : Merged and made usable non modular (its so tiny its silly as
* a module taking up 2 pages).
* Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
* to keep ip_forward happy.
* Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
* Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL
*
* 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.
*
*/
#include <linux/module.h>
#include <linux/config.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/in.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/if_arp.h>
#include <linux/mroute.h>
#include <net/datalink.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/protocol.h>
#include <net/ipip.h>
void ipip_err(struct sk_buff *skb, unsigned char *dp)
{
/* NI */
return;
}
/*
* The IPIP protocol driver.
*
* On entry here
* skb->data is the original IP header
* skb->nh points to the initial IP header.
* skb->h points at the new header.
*/
int ipip_rcv(struct sk_buff *skb, unsigned short len)
{
struct device *dev;
struct iphdr *iph;
#ifdef TUNNEL_DEBUG
printk("ipip_rcv: got a packet!\n");
#endif
/*
* Discard the original IP header
*/
skb->mac.raw = skb->data;
skb_pull(skb, skb->h.raw - skb->nh.raw);
/*
* Adjust pointers
*/
iph = skb->nh.iph;
skb->nh.iph = skb->h.ipiph;
memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
/*
* If you want to add LZ compressed IP or things like that here,
* and in drivers/net/tunnel.c are the places to add.
*/
skb->protocol = htons(ETH_P_IP);
skb->ip_summed = 0;
skb->pkt_type = PACKET_HOST;
/*
* Is it draconic? I do not think so. --ANK
*/
dev = ip_dev_find_tunnel(iph->daddr, iph->saddr);
if (dev == NULL) {
#ifdef CONFIG_IP_MROUTE
int vif;
if (!MULTICAST(skb->nh.iph->daddr) ||
!ipv4_config.multicast_route ||
LOCAL_MCAST(skb->nh.iph->daddr) ||
(vif=ip_mr_find_tunnel(iph->daddr, iph->saddr)) < 0)
{
#endif
kfree_skb(skb, FREE_READ);
return -EINVAL;
#ifdef CONFIG_IP_MROUTE
}
IPCB(skb)->flags |= IPSKB_TUNNELED;
IPCB(skb)->vif = vif;
dev = skb->dev;
#endif
}
skb->dev = dev;
dst_release(skb->dst);
skb->dst = NULL;
netif_rx(skb);
return(0);
}
#ifdef MODULE
static struct inet_protocol ipip_protocol = {
ipip_rcv, /* IPIP handler */
ipip_err, /* TUNNEL error control */
0, /* next */
IPPROTO_IPIP, /* protocol ID */
0, /* copy */
NULL, /* data */
"IPIP" /* name */
};
/*
* And now the modules code and kernel interface.
*/
int init_module( void)
{
inet_add_protocol(&ipip_protocol);
return 0;
}
void cleanup_module( void)
{
if ( inet_del_protocol(&ipip_protocol) < 0 )
printk(KERN_INFO "ipip close: can't remove protocol\n");
}
#endif
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