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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/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/firewall.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>
/*
* The IPIP protocol driver.
*
* On entry here
* skb->data is the original IP header
* skb->ip_hdr points to the initial IP header.
* skb->h.raw points at the new header.
*/
int ipip_rcv(struct sk_buff *skb, struct device *dev, struct options *opt,
__u32 daddr, unsigned short len, __u32 saddr,
int redo, struct inet_protocol *protocol)
{
/* Don't unlink in the middle of a turnaround */
MOD_INC_USE_COUNT;
#ifdef TUNNEL_DEBUG
printk("ipip_rcv: got a packet!\n");
#endif
/*
* Discard the original IP header
*/
skb->mac.raw = skb->data;
skb_pull(skb, ((struct iphdr *)skb->data)->ihl<<2);
/*
* Adjust pointers
*/
skb->h.iph=(struct iphdr *)skb->data;
skb->ip_hdr=(struct iphdr *)skb->data;
memset(skb->proto_priv, 0, sizeof(struct 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;
netif_rx(skb);
MOD_DEC_USE_COUNT;
return(0);
}
#ifdef MODULE
static struct inet_protocol ipip_protocol = {
ipip_rcv, /* IPIP handler */
#if 0
NULL, /* Will be UDP fraglist handler */
#endif
NULL, /* 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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