wanmain.c

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	default:
		printk(KERN_INFO
			"%s: unsupported NLPID 0x%02X on interface %s!\n",
			modname, skb->data[cnt], dev->name);
		return 0;
	}
	skb->protocol = ethertype;
	skb->pkt_type = PACKET_HOST;	/*	Physically point to point */
	skb->mac.raw  = skb->data;
	skb_pull(skb, cnt);
	return ethertype;
}


/*
 *	WAN device IOCTL.
 *	o find WAN device associated with this node
 *	o execute requested action or pass command to the device driver
 */

int wanrouter_ioctl(struct inode *inode, struct file *file,
		unsigned int cmd, unsigned long arg)
{
	int err = 0;
	struct proc_dir_entry *dent;
	wan_device_t *wandev;

	if (!capable(CAP_NET_ADMIN)){
		return -EPERM;
	}
		
	if ((cmd >> 8) != ROUTER_IOCTL)
		return -EINVAL;
		
	dent = inode->u.generic_ip;
	if ((dent == NULL) || (dent->data == NULL))
		return -EINVAL;
		
	wandev = dent->data;
	if (wandev->magic != ROUTER_MAGIC)
		return -EINVAL;
		
	switch (cmd) {
	case ROUTER_SETUP:
		err = device_setup(wandev, (void*)arg);
		break;

	case ROUTER_DOWN:
		err = device_shutdown(wandev);
		break;

	case ROUTER_STAT:
		err = device_stat(wandev, (void*)arg);
		break;

	case ROUTER_IFNEW:
		err = device_new_if(wandev, (void*)arg);
		break;

	case ROUTER_IFDEL:
		err = device_del_if(wandev, (void*)arg);
		break;

	case ROUTER_IFSTAT:
		break;

	default:
		if ((cmd >= ROUTER_USER) &&
		    (cmd <= ROUTER_USER_MAX) &&
		    wandev->ioctl)
			err = wandev->ioctl(wandev, cmd, arg);
		else err = -EINVAL;
	}
	return err;
}

/*
 *	WAN Driver IOCTL Handlers
 */

/*
 *	Setup WAN link device.
 *	o verify user address space
 *	o allocate kernel memory and copy configuration data to kernel space
 *	o if configuration data includes extension, copy it to kernel space too
 *	o call driver's setup() entry point
 */

static int device_setup (wan_device_t *wandev, wandev_conf_t *u_conf)
{
	void *data = NULL;
	wandev_conf_t *conf;
	int err = -EINVAL;

	if (wandev->setup == NULL)	/* Nothing to do ? */
		return 0;

	conf = kmalloc(sizeof(wandev_conf_t), GFP_KERNEL);
	if (conf == NULL)
		return -ENOBUFS;

	if(copy_from_user(conf, u_conf, sizeof(wandev_conf_t))) {
		kfree(conf);
		return -EFAULT;
	}
	
	if (conf->magic != ROUTER_MAGIC) {
		kfree(conf);
	        return -EINVAL; 
	}

	if (conf->data_size && conf->data) {
		if(conf->data_size > 128000 || conf->data_size < 0) {
			kfree(conf);
		        return -EINVAL;;
		}

		data = vmalloc(conf->data_size);
		if (data) {
			if(!copy_from_user(data, conf->data, conf->data_size)){
				conf->data=data;
				err = wandev->setup(wandev,conf);
			}
			else 
				err = -EFAULT;
		}
		else 
			err = -ENOBUFS;

		if (data)
			vfree(data);

	}

	kfree(conf);
	return err;
}

/*
 *	Shutdown WAN device.
 *	o delete all not opened logical channels for this device
 *	o call driver's shutdown() entry point
 */
 
static int device_shutdown (wan_device_t* wandev)
{
	struct net_device* dev;

	if (wandev->state == WAN_UNCONFIGURED)
		return 0;
		
	for (dev = wandev->dev; dev;)
	{
		if (delete_interface(wandev, dev->name, 0))
		{
			struct net_device **slave = dev->priv;
			dev = *slave;
		}
	}
	if (wandev->ndev)
		return -EBUSY;	/* there are opened interfaces  */
		
	if (wandev->shutdown)
		return wandev->shutdown(wandev);
	return 0;
}

/*
 *	Get WAN device status & statistics.
 */

static int device_stat (wan_device_t *wandev, wandev_stat_t *u_stat)
{
	wandev_stat_t stat;

	memset(&stat, 0, sizeof(stat));

	/* Ask device driver to update device statistics */
	if ((wandev->state != WAN_UNCONFIGURED) && wandev->update)
		wandev->update(wandev);

	/* Fill out structure */
	stat.ndev  = wandev->ndev;
	stat.state = wandev->state;

	if(copy_to_user(u_stat, &stat, sizeof(stat)))
		return -EFAULT;

	return 0;
}

/*
 *	Create new WAN interface.
 *	o verify user address space
 *	o copy configuration data to kernel address space
 *	o allocate network interface data space
 *	o call driver's new_if() entry point
 *	o make sure there is no interface name conflict
 *	o register network interface
 */

static int device_new_if (wan_device_t* wandev, wanif_conf_t* u_conf)
{
	wanif_conf_t conf;
	struct net_device *dev;
	int err;

	if ((wandev->state == WAN_UNCONFIGURED) || (wandev->new_if == NULL))
		return -ENODEV;
		
	if(copy_from_user(&conf, u_conf, sizeof(wanif_conf_t)))
		return -EFAULT;
		
	if (conf.magic != ROUTER_MAGIC)
		return -EINVAL;
		
	dev = kmalloc(sizeof(struct net_device), GFP_KERNEL);
	if (dev == NULL)
		return -ENOBUFS;
		
	memset(dev, 0, sizeof(struct net_device));
	err = wandev->new_if(wandev, dev, &conf);
	if (!err) {
		/* Register network interface. This will invoke init()
		 * function supplied by the driver.  If device registered
		 * successfully, add it to the interface list.
		 */
		if (dev->name == NULL)
			err = -EINVAL;
			
		else if (dev_get(dev->name))
			err = -EEXIST;	/* name already exists */
		else {
#ifdef WANDEBUG		
			printk(KERN_INFO "%s: registering interface %s...\n",
				modname, dev->name);
#endif				
			err = register_netdev(dev);
			if (!err) {
				struct net_device **slave = dev->priv;

				cli();	/***** critical section start *****/
				*slave = wandev->dev;
				wandev->dev = dev;
				++wandev->ndev;
				sti();	/****** critical section end ******/
				return 0;	/* done !!! */
			}
		}
		if (wandev->del_if)
			wandev->del_if(wandev, dev);
	}
	kfree(dev);
	return err;
}


/*
 *	Delete WAN logical channel.
 *	 o verify user address space
 *	 o copy configuration data to kernel address space
 */

static int device_del_if (wan_device_t *wandev, char *u_name)
{
	char name[WAN_IFNAME_SZ + 1];

	if (wandev->state == WAN_UNCONFIGURED)
		return -ENODEV;
	
	memset(name, 0, sizeof(name));

	if(copy_from_user(name, u_name, WAN_IFNAME_SZ))
		return -EFAULT;
	return delete_interface(wandev, name, 0);
}


/*
 *	Miscellaneous Functions
 */

/*
 *	Find WAN device by name.
 *	Return pointer to the WAN device data space or NULL if device not found.
 */

static wan_device_t *find_device(char *name)
{
	wan_device_t *wandev;

	for (wandev = router_devlist;wandev && strcmp(wandev->name, name);
		wandev = wandev->next);
	return wandev;
}

/*
 *	Delete WAN logical channel identified by its name.
 *	o find logical channel by its name
 *	o call driver's del_if() entry point
 *	o unregister network interface
 *	o unlink channel data space from linked list of channels
 *	o release channel data space
 *
 *	Return:	0		success
 *		-ENODEV		channel not found.
 *		-EBUSY		interface is open
 *
 *	Note: If (force != 0), then device will be destroyed even if interface
 *	associated with it is open. It's caller's responsibility to make
 *	sure that opened interfaces are not removed!
 */

static int delete_interface (wan_device_t *wandev, char *name, int force)
{
	struct net_device *dev, *prev;

	dev = wandev->dev;
	prev = NULL;
	while (dev && strcmp(name, dev->name)) {
		struct net_device **slave = dev->priv;

		prev = dev;
		dev = *slave;
	}

	if (dev == NULL)
		return -ENODEV;	/* interface not found */

	if (netif_running(dev)) {
		if (force) {
			printk(KERN_WARNING
				"%s: deleting opened interface %s!\n",
				modname, name);
		}
		else
			return -EBUSY;	/* interface in use */
	}

	if (wandev->del_if)
		wandev->del_if(wandev, dev);

	cli();			/***** critical section start *****/
	if (prev) {
		struct net_device **prev_slave = prev->priv;
		struct net_device **slave = dev->priv;

		*prev_slave = *slave;
	} else {
		struct net_device **slave = dev->priv;

		wandev->dev = *slave;
	}
	--wandev->ndev;
	sti();			/****** critical section end ******/

	printk("Unregistering '%s'\n", dev->name); 
	unregister_netdev(dev);
	kfree(dev);
	return 0;
}

EXPORT_SYMBOL(register_wan_device);
EXPORT_SYMBOL(unregister_wan_device);
EXPORT_SYMBOL(wanrouter_encapsulate);
EXPORT_SYMBOL(wanrouter_type_trans);

/*
 *	End
 */