[mirror_ubuntu-bionic-kernel.git] / drivers / net / wan / lapbether.c

/*
 *	"LAPB via ethernet" driver release 001
 *
 *	This code REQUIRES 2.1.15 or higher/ NET3.038
 *
 *	This module:
 *		This module 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.
 *
 *	This is a "pseudo" network driver to allow LAPB over Ethernet.
 *
 *	This driver can use any ethernet destination address, and can be 
 *	limited to accept frames from one dedicated ethernet card only.
 *
 *	History
 *	LAPBETH 001	Jonathan Naylor		Cloned from bpqether.c
 *	2000-10-29	Henner Eisen	lapb_data_indication() return status.
 *	2000-11-14	Henner Eisen	dev_hold/put, NETDEV_GOING_DOWN support
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/net.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <asm/uaccess.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/stat.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/lapb.h>
#include <linux/init.h>

#include <net/x25device.h>

static const u8 bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

/* If this number is made larger, check that the temporary string buffer
 * in lapbeth_new_device is large enough to store the probe device name.*/
#define MAXLAPBDEV 100

struct lapbethdev {
	struct list_head	node;
	struct net_device	*ethdev;	/* link to ethernet device */
	struct net_device	*axdev;		/* lapbeth device (lapb#) */
};

static LIST_HEAD(lapbeth_devices);

/* ------------------------------------------------------------------------ */

/*
 *	Get the LAPB device for the ethernet device
 */
static struct lapbethdev *lapbeth_get_x25_dev(struct net_device *dev)
{
	struct lapbethdev *lapbeth;

	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
		if (lapbeth->ethdev == dev) 
			return lapbeth;
	}
	return NULL;
}

static __inline__ int dev_is_ethdev(struct net_device *dev)
{
	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
}

/* ------------------------------------------------------------------------ */

/*
 *	Receive a LAPB frame via an ethernet interface.
 */
static int lapbeth_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
{
	int len, err;
	struct lapbethdev *lapbeth;

	if (dev_net(dev) != &init_net)
		goto drop;

	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
		return NET_RX_DROP;

	if (!pskb_may_pull(skb, 2))
		goto drop;

	rcu_read_lock();
	lapbeth = lapbeth_get_x25_dev(dev);
	if (!lapbeth)
		goto drop_unlock;
	if (!netif_running(lapbeth->axdev))
		goto drop_unlock;

	len = skb->data[0] + skb->data[1] * 256;
	dev->stats.rx_packets++;
	dev->stats.rx_bytes += len;

	skb_pull(skb, 2);	/* Remove the length bytes */
	skb_trim(skb, len);	/* Set the length of the data */

	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
		printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
		goto drop_unlock;
	}
out:
	rcu_read_unlock();
	return 0;
drop_unlock:
	kfree_skb(skb);
	goto out;
drop:
	kfree_skb(skb);
	return 0;
}

static int lapbeth_data_indication(struct net_device *dev, struct sk_buff *skb)
{
	unsigned char *ptr;

	skb_push(skb, 1);

	if (skb_cow(skb, 1))
		return NET_RX_DROP;

	ptr  = skb->data;
	*ptr = X25_IFACE_DATA;

	skb->protocol = x25_type_trans(skb, dev);
	return netif_rx(skb);
}

/*
 *	Send a LAPB frame via an ethernet interface
 */
static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
				      struct net_device *dev)
{
	int err;

	/*
	 * Just to be *really* sure not to send anything if the interface
	 * is down, the ethernet device may have gone.
	 */
	if (!netif_running(dev))
		goto drop;

	switch (skb->data[0]) {
	case X25_IFACE_DATA:
		break;
	case X25_IFACE_CONNECT:
		if ((err = lapb_connect_request(dev)) != LAPB_OK)
			pr_err("lapb_connect_request error: %d\n", err);
		goto drop;
	case X25_IFACE_DISCONNECT:
		if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
			pr_err("lapb_disconnect_request err: %d\n", err);
		/* Fall thru */
	default:
		goto drop;
	}

	skb_pull(skb, 1);

	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
		pr_err("lapb_data_request error - %d\n", err);
		goto drop;
	}
out:
	return NETDEV_TX_OK;
drop:
	kfree_skb(skb);
	goto out;
}

static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb)
{
	struct lapbethdev *lapbeth = netdev_priv(ndev);
	unsigned char *ptr;
	struct net_device *dev;
	int size = skb->len;

	skb->protocol = htons(ETH_P_X25);

	ptr = skb_push(skb, 2);

	*ptr++ = size % 256;
	*ptr++ = size / 256;

	ndev->stats.tx_packets++;
	ndev->stats.tx_bytes += size;

	skb->dev = dev = lapbeth->ethdev;

	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);

	dev_queue_xmit(skb);
}

static void lapbeth_connected(struct net_device *dev, int reason)
{
	unsigned char *ptr;
	struct sk_buff *skb = dev_alloc_skb(1);

	if (!skb) {
		pr_err("out of memory\n");
		return;
	}

	ptr  = skb_put(skb, 1);
	*ptr = X25_IFACE_CONNECT;

	skb->protocol = x25_type_trans(skb, dev);
	netif_rx(skb);
}

static void lapbeth_disconnected(struct net_device *dev, int reason)
{
	unsigned char *ptr;
	struct sk_buff *skb = dev_alloc_skb(1);

	if (!skb) {
		pr_err("out of memory\n");
		return;
	}

	ptr  = skb_put(skb, 1);
	*ptr = X25_IFACE_DISCONNECT;

	skb->protocol = x25_type_trans(skb, dev);
	netif_rx(skb);
}

/*
 *	Set AX.25 callsign
 */
static int lapbeth_set_mac_address(struct net_device *dev, void *addr)
{
	struct sockaddr *sa = addr;
	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
	return 0;
}


static const struct lapb_register_struct lapbeth_callbacks = {
	.connect_confirmation    = lapbeth_connected,
	.connect_indication      = lapbeth_connected,
	.disconnect_confirmation = lapbeth_disconnected,
	.disconnect_indication   = lapbeth_disconnected,
	.data_indication         = lapbeth_data_indication,
	.data_transmit           = lapbeth_data_transmit,
};

/*
 * open/close a device
 */
static int lapbeth_open(struct net_device *dev)
{
	int err;

	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
		pr_err("lapb_register error: %d\n", err);
		return -ENODEV;
	}

	netif_start_queue(dev);
	return 0;
}

static int lapbeth_close(struct net_device *dev)
{
	int err;

	netif_stop_queue(dev);

	if ((err = lapb_unregister(dev)) != LAPB_OK)
		pr_err("lapb_unregister error: %d\n", err);

	return 0;
}

/* ------------------------------------------------------------------------ */

static const struct net_device_ops lapbeth_netdev_ops = {
	.ndo_open	     = lapbeth_open,
	.ndo_stop	     = lapbeth_close,
	.ndo_start_xmit	     = lapbeth_xmit,
	.ndo_set_mac_address = lapbeth_set_mac_address,
};

static void lapbeth_setup(struct net_device *dev)
{
	dev->netdev_ops	     = &lapbeth_netdev_ops;
	dev->destructor	     = free_netdev;
	dev->type            = ARPHRD_X25;
	dev->hard_header_len = 3;
	dev->mtu             = 1000;
	dev->addr_len        = 0;
}

/*
 *	Setup a new device.
 */
static int lapbeth_new_device(struct net_device *dev)
{
	struct net_device *ndev;
	struct lapbethdev *lapbeth;
	int rc = -ENOMEM;

	ASSERT_RTNL();

	ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d", NET_NAME_UNKNOWN,
			    lapbeth_setup);
	if (!ndev)
		goto out;

	lapbeth = netdev_priv(ndev);
	lapbeth->axdev = ndev;

	dev_hold(dev);
	lapbeth->ethdev = dev;

	rc = -EIO;
	if (register_netdevice(ndev))
		goto fail;

	list_add_rcu(&lapbeth->node, &lapbeth_devices);
	rc = 0;
out:
	return rc;
fail:
	dev_put(dev);
	free_netdev(ndev);
	kfree(lapbeth);
	goto out;
}

/*
 *	Free a lapb network device.
 */
static void lapbeth_free_device(struct lapbethdev *lapbeth)
{
	dev_put(lapbeth->ethdev);
	list_del_rcu(&lapbeth->node);
	unregister_netdevice(lapbeth->axdev);
}

/*
 *	Handle device status changes.
 *
 * Called from notifier with RTNL held.
 */
static int lapbeth_device_event(struct notifier_block *this,
				unsigned long event, void *ptr)
{
	struct lapbethdev *lapbeth;
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);

	if (dev_net(dev) != &init_net)
		return NOTIFY_DONE;

	if (!dev_is_ethdev(dev))
		return NOTIFY_DONE;

	switch (event) {
	case NETDEV_UP:
		/* New ethernet device -> new LAPB interface	 */
		if (lapbeth_get_x25_dev(dev) == NULL)
			lapbeth_new_device(dev);
		break;
	case NETDEV_DOWN:	
		/* ethernet device closed -> close LAPB interface */
		lapbeth = lapbeth_get_x25_dev(dev);
		if (lapbeth) 
			dev_close(lapbeth->axdev);
		break;
	case NETDEV_UNREGISTER:
		/* ethernet device disappears -> remove LAPB interface */
		lapbeth = lapbeth_get_x25_dev(dev);
		if (lapbeth)
			lapbeth_free_device(lapbeth);
		break;
	}

	return NOTIFY_DONE;
}

/* ------------------------------------------------------------------------ */

static struct packet_type lapbeth_packet_type __read_mostly = {
	.type = cpu_to_be16(ETH_P_DEC),
	.func = lapbeth_rcv,
};

static struct notifier_block lapbeth_dev_notifier = {
	.notifier_call = lapbeth_device_event,
};

static const char banner[] __initconst =
	KERN_INFO "LAPB Ethernet driver version 0.02\n";

static int __init lapbeth_init_driver(void)
{
	dev_add_pack(&lapbeth_packet_type);

	register_netdevice_notifier(&lapbeth_dev_notifier);

	printk(banner);

	return 0;
}
module_init(lapbeth_init_driver);

static void __exit lapbeth_cleanup_driver(void)
{
	struct lapbethdev *lapbeth;
	struct list_head *entry, *tmp;

	dev_remove_pack(&lapbeth_packet_type);
	unregister_netdevice_notifier(&lapbeth_dev_notifier);

	rtnl_lock();
	list_for_each_safe(entry, tmp, &lapbeth_devices) {
		lapbeth = list_entry(entry, struct lapbethdev, node);

		dev_put(lapbeth->ethdev);
		unregister_netdevice(lapbeth->axdev);
	}
	rtnl_unlock();
}
module_exit(lapbeth_cleanup_driver);

MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* "LAPB via ethernet" driver release 001
	3	*
	4	* This code REQUIRES 2.1.15 or higher/ NET3.038
	5	*
	6	* This module:
	7	* This module is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* as published by the Free Software Foundation; either version
	10	* 2 of the License, or (at your option) any later version.
	11	*
	12	* This is a "pseudo" network driver to allow LAPB over Ethernet.
	13	*
	14	* This driver can use any ethernet destination address, and can be
	15	* limited to accept frames from one dedicated ethernet card only.
	16	*
	17	* History
	18	* LAPBETH 001 Jonathan Naylor Cloned from bpqether.c
	19	* 2000-10-29 Henner Eisen lapb_data_indication() return status.
	20	* 2000-11-14 Henner Eisen dev_hold/put, NETDEV_GOING_DOWN support
	21	*/
	22
23efcb73 JP	23	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23efcb73 JP	24
1da177e4 LT	25	#include <linux/errno.h>
	26	#include <linux/types.h>
	27	#include <linux/socket.h>
	28	#include <linux/in.h>
5a0e3ad6	29	#include <linux/slab.h>
1da177e4 LT	30	#include <linux/kernel.h>
	31	#include <linux/string.h>
	32	#include <linux/net.h>
	33	#include <linux/inet.h>
	34	#include <linux/netdevice.h>
	35	#include <linux/if_arp.h>
	36	#include <linux/skbuff.h>
	37	#include <net/sock.h>
1da177e4 LT	38	#include <asm/uaccess.h>
	39	#include <linux/mm.h>
	40	#include <linux/interrupt.h>
	41	#include <linux/notifier.h>
	42	#include <linux/stat.h>
	43	#include <linux/netfilter.h>
	44	#include <linux/module.h>
	45	#include <linux/lapb.h>
	46	#include <linux/init.h>
	47
	48	#include <net/x25device.h>
	49
dcfc5d78	50	static const u8 bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
1da177e4 LT	51
	52	/* If this number is made larger, check that the temporary string buffer
	53	* in lapbeth_new_device is large enough to store the probe device name.*/
	54	#define MAXLAPBDEV 100
	55
	56	struct lapbethdev {
	57	struct list_head node;
	58	struct net_device ethdev; / link to ethernet device */
	59	struct net_device axdev; / lapbeth device (lapb#) */
1da177e4 LT	60	};
1da177e4 LT	61
293a3839	62	static LIST_HEAD(lapbeth_devices);
1da177e4 LT	63
	64	/* ------------------------------------------------------------------------ */
	65
	66	/*
	67	* Get the LAPB device for the ethernet device
	68	*/
	69	static struct lapbethdev lapbeth_get_x25_dev(struct net_device dev)
	70	{
	71	struct lapbethdev *lapbeth;
	72
	73	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
	74	if (lapbeth->ethdev == dev)
	75	return lapbeth;
	76	}
	77	return NULL;
	78	}
	79
	80	static __inline__ int dev_is_ethdev(struct net_device *dev)
	81	{
	82	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
	83	}
	84
	85	/* ------------------------------------------------------------------------ */
	86
	87	/*
	88	* Receive a LAPB frame via an ethernet interface.
	89	*/
f2ccd8fa	90	static int lapbeth_rcv(struct sk_buff skb, struct net_device dev, struct packet_type ptype, struct net_device orig_dev)
1da177e4 LT	91	{
	92	int len, err;
	93	struct lapbethdev *lapbeth;
	94
c346dca1	95	if (dev_net(dev) != &init_net)
e730c155 EB	96	goto drop;
e730c155 EB	97
1da177e4 LT	98	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
	99	return NET_RX_DROP;
	100
	101	if (!pskb_may_pull(skb, 2))
	102	goto drop;
	103
	104	rcu_read_lock();
	105	lapbeth = lapbeth_get_x25_dev(dev);
	106	if (!lapbeth)
	107	goto drop_unlock;
	108	if (!netif_running(lapbeth->axdev))
	109	goto drop_unlock;
	110
1da177e4	111	len = skb->data[0] + skb->data[1] * 256;
ea2ebaf8 SH	112	dev->stats.rx_packets++;
ea2ebaf8 SH	113	dev->stats.rx_bytes += len;
1da177e4 LT	114
	115	skb_pull(skb, 2); /* Remove the length bytes */
	116	skb_trim(skb, len); /* Set the length of the data */
	117
	118	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
	119	printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
	120	goto drop_unlock;
	121	}
	122	out:
	123	rcu_read_unlock();
	124	return 0;
	125	drop_unlock:
	126	kfree_skb(skb);
	127	goto out;
	128	drop:
	129	kfree_skb(skb);
	130	return 0;
	131	}
	132
	133	static int lapbeth_data_indication(struct net_device dev, struct sk_buff skb)
	134	{
	135	unsigned char *ptr;
	136
	137	skb_push(skb, 1);
	138
	139	if (skb_cow(skb, 1))
	140	return NET_RX_DROP;
	141
	142	ptr = skb->data;
4d99503e	143	*ptr = X25_IFACE_DATA;
1da177e4 LT	144
1da177e4 LT	145	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	146	return netif_rx(skb);
	147	}
	148
	149	/*
	150	* Send a LAPB frame via an ethernet interface
	151	*/
d71a6749 SH	152	static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
d71a6749 SH	153	struct net_device *dev)
1da177e4	154	{
d77eeb70	155	int err;
1da177e4 LT	156
	157	/*
	158	* Just to be really sure not to send anything if the interface
	159	* is down, the ethernet device may have gone.
	160	*/
d77eeb70	161	if (!netif_running(dev))
1da177e4	162	goto drop;
1da177e4 LT	163
1da177e4 LT	164	switch (skb->data[0]) {
4d99503e	165	case X25_IFACE_DATA:
1da177e4	166	break;
4d99503e	167	case X25_IFACE_CONNECT:
1da177e4	168	if ((err = lapb_connect_request(dev)) != LAPB_OK)
23efcb73	169	pr_err("lapb_connect_request error: %d\n", err);
d77eeb70	170	goto drop;
4d99503e	171	case X25_IFACE_DISCONNECT:
1da177e4	172	if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
23efcb73	173	pr_err("lapb_disconnect_request err: %d\n", err);
1da177e4 LT	174	/* Fall thru */
1da177e4 LT	175	default:
d77eeb70	176	goto drop;
1da177e4 LT	177	}
	178
	179	skb_pull(skb, 1);
	180
	181	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
23efcb73	182	pr_err("lapb_data_request error - %d\n", err);
1da177e4 LT	183	goto drop;
1da177e4 LT	184	}
1da177e4	185	out:
d77eeb70	186	return NETDEV_TX_OK;
1da177e4 LT	187	drop:
	188	kfree_skb(skb);
	189	goto out;
	190	}
	191
	192	static void lapbeth_data_transmit(struct net_device ndev, struct sk_buff skb)
	193	{
	194	struct lapbethdev *lapbeth = netdev_priv(ndev);
	195	unsigned char *ptr;
	196	struct net_device *dev;
	197	int size = skb->len;
	198
	199	skb->protocol = htons(ETH_P_X25);
	200
	201	ptr = skb_push(skb, 2);
	202
	203	*ptr++ = size % 256;
	204	*ptr++ = size / 256;
	205
ea2ebaf8 SH	206	ndev->stats.tx_packets++;
ea2ebaf8 SH	207	ndev->stats.tx_bytes += size;
1da177e4 LT	208
	209	skb->dev = dev = lapbeth->ethdev;
	210
0c4e8581	211	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
1da177e4 LT	212
	213	dev_queue_xmit(skb);
	214	}
	215
	216	static void lapbeth_connected(struct net_device *dev, int reason)
	217	{
	218	unsigned char *ptr;
	219	struct sk_buff *skb = dev_alloc_skb(1);
	220
	221	if (!skb) {
23efcb73	222	pr_err("out of memory\n");
1da177e4 LT	223	return;
	224	}
	225
	226	ptr = skb_put(skb, 1);
4d99503e	227	*ptr = X25_IFACE_CONNECT;
1da177e4 LT	228
1da177e4 LT	229	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	230	netif_rx(skb);
	231	}
	232
	233	static void lapbeth_disconnected(struct net_device *dev, int reason)
	234	{
	235	unsigned char *ptr;
	236	struct sk_buff *skb = dev_alloc_skb(1);
	237
	238	if (!skb) {
23efcb73	239	pr_err("out of memory\n");
1da177e4 LT	240	return;
	241	}
	242
	243	ptr = skb_put(skb, 1);
4d99503e	244	*ptr = X25_IFACE_DISCONNECT;
1da177e4 LT	245
1da177e4 LT	246	skb->protocol = x25_type_trans(skb, dev);
1da177e4 LT	247	netif_rx(skb);
	248	}
	249
1da177e4 LT	250	/*
	251	* Set AX.25 callsign
	252	*/
	253	static int lapbeth_set_mac_address(struct net_device dev, void addr)
	254	{
	255	struct sockaddr *sa = addr;
	256	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
	257	return 0;
	258	}
	259
	260
d97a077a	261	static const struct lapb_register_struct lapbeth_callbacks = {
1da177e4 LT	262	.connect_confirmation = lapbeth_connected,
	263	.connect_indication = lapbeth_connected,
	264	.disconnect_confirmation = lapbeth_disconnected,
	265	.disconnect_indication = lapbeth_disconnected,
	266	.data_indication = lapbeth_data_indication,
	267	.data_transmit = lapbeth_data_transmit,
1da177e4 LT	268	};
	269
	270	/*
	271	* open/close a device
	272	*/
	273	static int lapbeth_open(struct net_device *dev)
	274	{
	275	int err;
	276
	277	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
23efcb73	278	pr_err("lapb_register error: %d\n", err);
1da177e4 LT	279	return -ENODEV;
	280	}
	281
	282	netif_start_queue(dev);
	283	return 0;
	284	}
	285
	286	static int lapbeth_close(struct net_device *dev)
	287	{
	288	int err;
	289
	290	netif_stop_queue(dev);
	291
	292	if ((err = lapb_unregister(dev)) != LAPB_OK)
23efcb73	293	pr_err("lapb_unregister error: %d\n", err);
1da177e4 LT	294
	295	return 0;
	296	}
	297
	298	/* ------------------------------------------------------------------------ */
	299
39549b1e SH	300	static const struct net_device_ops lapbeth_netdev_ops = {
	301	.ndo_open = lapbeth_open,
	302	.ndo_stop = lapbeth_close,
	303	.ndo_start_xmit = lapbeth_xmit,
	304	.ndo_set_mac_address = lapbeth_set_mac_address,
	305	};
	306
1da177e4 LT	307	static void lapbeth_setup(struct net_device *dev)
1da177e4 LT	308	{
39549b1e	309	dev->netdev_ops = &lapbeth_netdev_ops;
1da177e4	310	dev->destructor = free_netdev;
1da177e4 LT	311	dev->type = ARPHRD_X25;
	312	dev->hard_header_len = 3;
	313	dev->mtu = 1000;
	314	dev->addr_len = 0;
1da177e4 LT	315	}
	316
	317	/*
	318	* Setup a new device.
	319	*/
	320	static int lapbeth_new_device(struct net_device *dev)
	321	{
	322	struct net_device *ndev;
	323	struct lapbethdev *lapbeth;
	324	int rc = -ENOMEM;
	325
	326	ASSERT_RTNL();
	327
c835a677 TG	328	ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d", NET_NAME_UNKNOWN,
c835a677 TG	329	lapbeth_setup);
1da177e4 LT	330	if (!ndev)
	331	goto out;
	332
	333	lapbeth = netdev_priv(ndev);
	334	lapbeth->axdev = ndev;
	335
	336	dev_hold(dev);
	337	lapbeth->ethdev = dev;
	338
1da177e4 LT	339	rc = -EIO;
	340	if (register_netdevice(ndev))
	341	goto fail;
	342
	343	list_add_rcu(&lapbeth->node, &lapbeth_devices);
	344	rc = 0;
	345	out:
	346	return rc;
	347	fail:
	348	dev_put(dev);
	349	free_netdev(ndev);
	350	kfree(lapbeth);
	351	goto out;
	352	}
	353
	354	/*
	355	* Free a lapb network device.
	356	*/
	357	static void lapbeth_free_device(struct lapbethdev *lapbeth)
	358	{
	359	dev_put(lapbeth->ethdev);
	360	list_del_rcu(&lapbeth->node);
	361	unregister_netdevice(lapbeth->axdev);
	362	}
	363
	364	/*
	365	* Handle device status changes.
	366	*
	367	* Called from notifier with RTNL held.
	368	*/
	369	static int lapbeth_device_event(struct notifier_block *this,
	370	unsigned long event, void *ptr)
	371	{
	372	struct lapbethdev *lapbeth;
351638e7	373	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1da177e4	374
c346dca1	375	if (dev_net(dev) != &init_net)
e9dc8653 EB	376	return NOTIFY_DONE;
e9dc8653 EB	377
1da177e4 LT	378	if (!dev_is_ethdev(dev))
	379	return NOTIFY_DONE;
	380
	381	switch (event) {
	382	case NETDEV_UP:
	383	/* New ethernet device -> new LAPB interface */
	384	if (lapbeth_get_x25_dev(dev) == NULL)
	385	lapbeth_new_device(dev);
	386	break;
	387	case NETDEV_DOWN:
	388	/* ethernet device closed -> close LAPB interface */
	389	lapbeth = lapbeth_get_x25_dev(dev);
	390	if (lapbeth)
	391	dev_close(lapbeth->axdev);
	392	break;
	393	case NETDEV_UNREGISTER:
	394	/* ethernet device disappears -> remove LAPB interface */
	395	lapbeth = lapbeth_get_x25_dev(dev);
	396	if (lapbeth)
	397	lapbeth_free_device(lapbeth);
	398	break;
	399	}
	400
	401	return NOTIFY_DONE;
	402	}
	403
	404	/* ------------------------------------------------------------------------ */
	405
7546dd97	406	static struct packet_type lapbeth_packet_type __read_mostly = {
09640e63	407	.type = cpu_to_be16(ETH_P_DEC),
1da177e4 LT	408	.func = lapbeth_rcv,
	409	};
	410
	411	static struct notifier_block lapbeth_dev_notifier = {
	412	.notifier_call = lapbeth_device_event,
	413	};
	414
81b700b1	415	static const char banner[] __initconst =
5ee0d593	416	KERN_INFO "LAPB Ethernet driver version 0.02\n";
1da177e4 LT	417
	418	static int __init lapbeth_init_driver(void)
	419	{
	420	dev_add_pack(&lapbeth_packet_type);
	421
	422	register_netdevice_notifier(&lapbeth_dev_notifier);
	423
	424	printk(banner);
	425
	426	return 0;
	427	}
	428	module_init(lapbeth_init_driver);
	429
	430	static void __exit lapbeth_cleanup_driver(void)
	431	{
	432	struct lapbethdev *lapbeth;
	433	struct list_head entry, tmp;
	434
	435	dev_remove_pack(&lapbeth_packet_type);
	436	unregister_netdevice_notifier(&lapbeth_dev_notifier);
	437
	438	rtnl_lock();
	439	list_for_each_safe(entry, tmp, &lapbeth_devices) {
	440	lapbeth = list_entry(entry, struct lapbethdev, node);
	441
e544ff00	442	dev_put(lapbeth->ethdev);
1da177e4 LT	443	unregister_netdevice(lapbeth->axdev);
	444	}
	445	rtnl_unlock();
	446	}
	447	module_exit(lapbeth_cleanup_driver);
	448
	449	MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
	450	MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
	451	MODULE_LICENSE("GPL");