patch-1.3.71 linux/drivers/net/tunnel.c

• Lines: 314
• Date: Thu Jan 1 02:00:00 1970
• Orig file: v1.3.70/linux/drivers/net/tunnel.c
• Orig date: Wed Feb 7 15:11:27 1996

diff -u --recursive --new-file v1.3.70/linux/drivers/net/tunnel.c linux/drivers/net/tunnel.c
@@ -1,313 +0,0 @@
-/* tunnel.c: an IP tunnel driver
-
-	The purpose of this driver is to provide an IP tunnel through
-	which you can tunnel network traffic transparently across subnets.
-
-	This was written by looking at Nick Holloway's dummy driver
-	Thanks for the great code!
-
-		-Sam Lantinga	(slouken@cs.ucdavis.edu)  02/01/95
-		
-	Minor tweaks:
-		Cleaned up the code a little and added some pre-1.3.0 tweaks.
-		dev->hard_header/hard_header_len changed to use no headers.
-		Comments/bracketing tweaked.
-		Made the tunnels use dev->name not tunnel: when error reporting.
-		Added tx_dropped stat
-		
-		-Alan Cox	(Alan.Cox@linux.org) 21 March 95
-*/
-
-#include <linux/module.h>
-
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/types.h>
-#include <netinet/in.h>
-#include <linux/ip.h>
-#include <linux/string.h>
-#include <asm/system.h>
-#include <linux/errno.h>
-
-#include <linux/netdevice.h>
-#include <linux/etherdevice.h>
-#include <linux/if_arp.h>
-#include <linux/skbuff.h>
-#include <net/ip.h>
-
-#include <net/checksum.h>		/* If using 1.3.0-pre net code */
-
-#define ip_header_len	sizeof(struct iphdr)
-
-static int tunnel_xmit(struct sk_buff *skb, struct device *dev);
-static struct enet_statistics *tunnel_get_stats(struct device *dev);
-
-#ifdef MODULE
-static int tunnel_open(struct device *dev)
-{
-	MOD_INC_USE_COUNT;
-	return 0;
-}
-
-static int tunnel_close(struct device *dev)
-{
-	MOD_DEC_USE_COUNT;
-	return 0;
-}
-
-#endif
-
-
-int tunnel_init(struct device *dev)
-{
-	static int tun_msg=0;
-	if(!tun_msg)
-	{
-		printk ( KERN_INFO "tunnel: version v0.1a\n" );
-		tun_msg=1;
-	}
-
-	/* Fill in fields of the dev structure with ethernet-generic values. */
-	ether_setup(dev);
-
-	/* Custom initialize the device structure. */
-	dev->hard_start_xmit = tunnel_xmit;
-	dev->get_stats = tunnel_get_stats;
-	dev->priv = kmalloc(sizeof(struct enet_statistics), GFP_KERNEL);
-	if (dev->priv == NULL)
-		return -ENOMEM;
-	memset(dev->priv, 0, sizeof(struct enet_statistics));
-#ifdef MODULE
-	dev->open = &tunnel_open;
-	dev->stop = &tunnel_close;
-#endif
-	/* Now stomp the bits that are different */
-	dev->type = ARPHRD_TUNNEL; 	/* IP tunnel hardware type (Linux 1.1.89) */
-	dev->flags |= IFF_NOARP;
-	dev->flags |= IFF_LOOPBACK; 	/* Why doesn't tunnel work without this? [ should do now - AC]*/
-	dev->addr_len=0;
-	dev->tx_queue_len=2;		/* Small queue - it should all run through */
-	dev->hard_header_len=0;
-	dev->hard_header=NULL;
-	dev->header_cache_bind=NULL;
-	dev->rebuild_header=NULL;
-	/* End of stomp 8) */
-	return 0;
-}
-
-#ifdef TUNNEL_DEBUG
-void print_ip(struct iphdr *ip)
-{
-	unsigned char *ipaddr;
-
-	printk("IP packet:\n");
-	printk("--- header len = %d\n", ip->ihl*4);
-	printk("--- ip version: %d\n", ip->version);
-	printk("--- ip protocol: %d\n", ip->protocol);
-	ipaddr=(unsigned char *)&ip->saddr;
-	printk("--- source address: %u.%u.%u.%u\n", 
-			*ipaddr, *(ipaddr+1), *(ipaddr+2), *(ipaddr+3));
-	ipaddr=(unsigned char *)&ip->daddr;
-	printk("--- destination address: %u.%u.%u.%u\n", 
-			*ipaddr, *(ipaddr+1), *(ipaddr+2), *(ipaddr+3));
-	printk("--- total packet len: %d\n", ntohs(ip->tot_len));
-}
-#endif
-
-/* This function assumes it is being called from dev_queue_xmit()
-   and that skb is filled properly by that function.
-   We also presume that if we return 0, we need to free skb, but
-   if we return 1, we don't free anything.  Right?  Wrong?
-*/
-
-static int tunnel_xmit(struct sk_buff *skb, struct device *dev)
-{
-	struct enet_statistics *stats;
-	struct sk_buff *skb2;		/* The output packet */
-	int newlen;			/* The length of skb2->data */
-	struct iphdr *iph;		/* Our new IP header */
-
-	/*
-	 *	Return if there is nothing to do 
-	 */
-	 
-	if (skb == NULL || dev == NULL)
-		return 0;
-
-	/* 
-	 *	Make sure we are not busy (check lock variable) 
-	 */
-	 
-	stats = (struct enet_statistics *)dev->priv;
-	cli();
-	if (dev->tbusy != 0) 
-	{
-		sti();
-		stats->tx_errors++;
-		return(1);
-	}
-	dev->tbusy = 1;
-	sti();
-  
-	/*
-	 *	Perform some sanity checks on the packet 
-	 */
-	 
-	if ( ! dev->pa_dstaddr ) 
-	{
-		printk("%s: packet sent through tunnel to never-never land!\n", dev->name);
-  		dev_kfree_skb(skb, FREE_WRITE);
-		dev->tbusy = 0;
-		return(1);
-	}
-
-	iph=(struct iphdr *)skb->data;
-	if ( iph->version != 4 ) 
-	{  
-		/* 
-		 *	Bad IP packet? Possibly an ARP packet 
-		 */
-		printk("%s: Bad IP packet: ip version %d\n", dev->name, iph->version);
-		dev_kfree_skb(skb, FREE_WRITE);
-		dev->tbusy = 0;
-		return(0);
-	}
-
-
-	/* 
-	 *	Check for routing loops 
-	 */
-	 
-	if ( iph->protocol == IPPROTO_IPIP && iph->saddr == dev->pa_addr ) 
-	{
-		/* 
-		 *	We really should do an ICMP reply here... 
-		 */
-		printk("%s: Warning: IP routing loop!\n", dev->name);
-		dev->tbusy = 0;
-		dev_kfree_skb(skb, FREE_WRITE);
-		return(0);
-	}
-
-	if ( iph->daddr == dev->pa_addr ) 
-	{
-		printk("%s: Received inbound packet -- not handled.\n",dev->name);
-  		dev_kfree_skb(skb, FREE_WRITE);
-		dev->tbusy = 0;
-		return(0);
-	}
-
-#ifdef TUNNEL_DEBUG
-printk("Old IP Header....\n");
-print_ip(iph);
-#endif
-	/*
-	 * Everything is okay: 
-	 *		See if we need to allocate memory for a new packet 
-	 */
-
-	newlen = (skb->len + ip_header_len);
-	if ( !(skb2 = dev_alloc_skb(newlen)) ) 
-	{
-		printk("%s: No free memory.\n",dev->name);
-  		dev_kfree_skb(skb, FREE_WRITE);
-  		dev->tbusy = 0;
-  		stats->tx_dropped++;
-		return(1);
-	}
-
-	/* Copy the packet to a new buffer, adding a new ip header */
-	skb2->free=1;
-	skb_put(skb2,newlen);
-	iph=skb2->h.iph=(struct iphdr *)skb2->data;
-	skb2->ip_hdr=iph;
-	memcpy(skb2->h.iph, skb->data, ip_header_len );
-	memcpy(skb2->data + ip_header_len, skb->data, skb->len);
-	/* Free the old packet, we no longer need it */
-	dev_kfree_skb(skb, FREE_WRITE);
-
-	/* Correct the fields in the new ip header */
-	++iph->ttl;	/* Note: ip_forward() decrements ttl, so compensate */
-	iph->saddr = dev->pa_addr;
-	iph->daddr = dev->pa_dstaddr;
-	iph->protocol = IPPROTO_IPIP;
-	iph->ihl = 5;
-	iph->tot_len = htons(skb2->len);
-	iph->frag_off = 0;
-
-	/* Here is where we compute the IP checksum */
-	/* ip_fast_csum() is an inline function from net/inet/ip.h/checksum.h */
-	iph->check = 0;
-	iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
-
-#ifdef TUNNEL_DEBUG
-printk("New IP Header....\n");
-print_ip(iph);
-#endif
-	/* Now send the packet on its way */
-#ifdef TUNNEL_DEBUG
-	printk("tunnel: calling ip_forward()\n");
-#endif
-	if(ip_forward(skb2, dev, 0, iph->daddr))
-		kfree_skb(skb2, FREE_WRITE);
-
- 
-#ifdef TUNNEL_DEBUG
-	printk("Packet sent through tunnel interface!\n");
-#endif
-	/* Record statistics */
-	stats->tx_packets++;
-
-#ifdef TUNNEL_DEBUG
-	printk("tunnel: Updated usage statistics.\n");
-#endif
-	dev->tbusy=0;
-	return 0;
-}
-
-static struct enet_statistics *
-tunnel_get_stats(struct device *dev)
-{
-	return((struct enet_statistics*) dev->priv);
-}
-
-#ifdef MODULE
-
-static int tunnel_probe(struct device *dev)
-{
-	tunnel_init(dev);
-	return 0;
-}
-
-static struct device dev_tunnel = {
-	"tunl0\0   ", 
-		0, 0, 0, 0,
-	 	0x0, 0,
-	 	0, 0, 0, NULL, tunnel_probe };
-
-int init_module(void)
-{
-	/* Find a name for this unit */
-	int ct= 1;
-	
-	while(dev_get(dev_tunnel.name)!=NULL && ct<100)
-	{
-		sprintf(dev_tunnel.name,"tunl%d",ct);
-		ct++;
-	}
-	
-#ifdef TUNNEL_DEBUG
-	printk("tunnel: registering device %s\n", dev_tunnel.name);
-#endif
-	if (register_netdev(&dev_tunnel) != 0)
-		return -EIO;
-	return 0;
-}
-
-void cleanup_module(void)
-{
-	unregister_netdev(&dev_tunnel);
-	kfree_s(dev_tunnel.priv,sizeof(struct enet_statistics));
-	dev_tunnel.priv=NULL;
-}
-#endif /* MODULE */