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v4.10.11
  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
 23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 24
 25#include <linux/errno.h>
 26#include <linux/types.h>
 27#include <linux/socket.h>
 28#include <linux/in.h>
 29#include <linux/slab.h>
 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>
 38#include <linux/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/module.h>
 44#include <linux/lapb.h>
 45#include <linux/init.h>
 46
 47#include <net/x25device.h>
 48
 49static const u8 bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
 50
 51/* If this number is made larger, check that the temporary string buffer
 52 * in lapbeth_new_device is large enough to store the probe device name.*/
 53#define MAXLAPBDEV 100
 54
 55struct lapbethdev {
 56	struct list_head	node;
 57	struct net_device	*ethdev;	/* link to ethernet device */
 58	struct net_device	*axdev;		/* lapbeth device (lapb#) */
 59};
 60
 61static LIST_HEAD(lapbeth_devices);
 62
 63/* ------------------------------------------------------------------------ */
 64
 65/*
 66 *	Get the LAPB device for the ethernet device
 67 */
 68static struct lapbethdev *lapbeth_get_x25_dev(struct net_device *dev)
 69{
 70	struct lapbethdev *lapbeth;
 71
 72	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
 73		if (lapbeth->ethdev == dev) 
 74			return lapbeth;
 75	}
 76	return NULL;
 77}
 78
 79static __inline__ int dev_is_ethdev(struct net_device *dev)
 80{
 81	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
 82}
 83
 84/* ------------------------------------------------------------------------ */
 85
 86/*
 87 *	Receive a LAPB frame via an ethernet interface.
 88 */
 89static int lapbeth_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
 90{
 91	int len, err;
 92	struct lapbethdev *lapbeth;
 93
 94	if (dev_net(dev) != &init_net)
 95		goto drop;
 96
 97	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 98		return NET_RX_DROP;
 99
100	if (!pskb_may_pull(skb, 2))
101		goto drop;
102
103	rcu_read_lock();
104	lapbeth = lapbeth_get_x25_dev(dev);
105	if (!lapbeth)
106		goto drop_unlock;
107	if (!netif_running(lapbeth->axdev))
108		goto drop_unlock;
109
110	len = skb->data[0] + skb->data[1] * 256;
111	dev->stats.rx_packets++;
112	dev->stats.rx_bytes += len;
113
114	skb_pull(skb, 2);	/* Remove the length bytes */
115	skb_trim(skb, len);	/* Set the length of the data */
116
117	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
118		printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
119		goto drop_unlock;
120	}
121out:
122	rcu_read_unlock();
123	return 0;
124drop_unlock:
125	kfree_skb(skb);
126	goto out;
127drop:
128	kfree_skb(skb);
129	return 0;
130}
131
132static int lapbeth_data_indication(struct net_device *dev, struct sk_buff *skb)
133{
134	unsigned char *ptr;
135
136	skb_push(skb, 1);
137
138	if (skb_cow(skb, 1))
139		return NET_RX_DROP;
140
141	ptr  = skb->data;
142	*ptr = X25_IFACE_DATA;
143
144	skb->protocol = x25_type_trans(skb, dev);
145	return netif_rx(skb);
146}
147
148/*
149 *	Send a LAPB frame via an ethernet interface
150 */
151static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
152				      struct net_device *dev)
153{
154	int err;
155
156	/*
157	 * Just to be *really* sure not to send anything if the interface
158	 * is down, the ethernet device may have gone.
159	 */
160	if (!netif_running(dev))
161		goto drop;
162
163	switch (skb->data[0]) {
164	case X25_IFACE_DATA:
165		break;
166	case X25_IFACE_CONNECT:
167		if ((err = lapb_connect_request(dev)) != LAPB_OK)
168			pr_err("lapb_connect_request error: %d\n", err);
169		goto drop;
170	case X25_IFACE_DISCONNECT:
171		if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
172			pr_err("lapb_disconnect_request err: %d\n", err);
173		/* Fall thru */
174	default:
175		goto drop;
176	}
177
178	skb_pull(skb, 1);
179
180	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
181		pr_err("lapb_data_request error - %d\n", err);
182		goto drop;
183	}
184out:
185	return NETDEV_TX_OK;
186drop:
187	kfree_skb(skb);
188	goto out;
189}
190
191static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb)
192{
193	struct lapbethdev *lapbeth = netdev_priv(ndev);
194	unsigned char *ptr;
195	struct net_device *dev;
196	int size = skb->len;
197
198	skb->protocol = htons(ETH_P_X25);
199
200	ptr = skb_push(skb, 2);
201
202	*ptr++ = size % 256;
203	*ptr++ = size / 256;
204
205	ndev->stats.tx_packets++;
206	ndev->stats.tx_bytes += size;
207
208	skb->dev = dev = lapbeth->ethdev;
209
210	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
211
212	dev_queue_xmit(skb);
213}
214
215static void lapbeth_connected(struct net_device *dev, int reason)
216{
217	unsigned char *ptr;
218	struct sk_buff *skb = dev_alloc_skb(1);
219
220	if (!skb) {
221		pr_err("out of memory\n");
222		return;
223	}
224
225	ptr  = skb_put(skb, 1);
226	*ptr = X25_IFACE_CONNECT;
227
228	skb->protocol = x25_type_trans(skb, dev);
229	netif_rx(skb);
230}
231
232static void lapbeth_disconnected(struct net_device *dev, int reason)
233{
234	unsigned char *ptr;
235	struct sk_buff *skb = dev_alloc_skb(1);
236
237	if (!skb) {
238		pr_err("out of memory\n");
239		return;
240	}
241
242	ptr  = skb_put(skb, 1);
243	*ptr = X25_IFACE_DISCONNECT;
244
245	skb->protocol = x25_type_trans(skb, dev);
246	netif_rx(skb);
247}
248
249/*
250 *	Set AX.25 callsign
251 */
252static int lapbeth_set_mac_address(struct net_device *dev, void *addr)
253{
254	struct sockaddr *sa = addr;
255	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
256	return 0;
257}
258
259
260static const struct lapb_register_struct lapbeth_callbacks = {
261	.connect_confirmation    = lapbeth_connected,
262	.connect_indication      = lapbeth_connected,
263	.disconnect_confirmation = lapbeth_disconnected,
264	.disconnect_indication   = lapbeth_disconnected,
265	.data_indication         = lapbeth_data_indication,
266	.data_transmit           = lapbeth_data_transmit,
 
267};
268
269/*
270 * open/close a device
271 */
272static int lapbeth_open(struct net_device *dev)
273{
274	int err;
275
276	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
277		pr_err("lapb_register error: %d\n", err);
278		return -ENODEV;
279	}
280
281	netif_start_queue(dev);
282	return 0;
283}
284
285static int lapbeth_close(struct net_device *dev)
286{
287	int err;
288
289	netif_stop_queue(dev);
290
291	if ((err = lapb_unregister(dev)) != LAPB_OK)
292		pr_err("lapb_unregister error: %d\n", err);
293
294	return 0;
295}
296
297/* ------------------------------------------------------------------------ */
298
299static const struct net_device_ops lapbeth_netdev_ops = {
300	.ndo_open	     = lapbeth_open,
301	.ndo_stop	     = lapbeth_close,
302	.ndo_start_xmit	     = lapbeth_xmit,
303	.ndo_set_mac_address = lapbeth_set_mac_address,
304};
305
306static void lapbeth_setup(struct net_device *dev)
307{
308	dev->netdev_ops	     = &lapbeth_netdev_ops;
309	dev->destructor	     = free_netdev;
310	dev->type            = ARPHRD_X25;
311	dev->hard_header_len = 3;
312	dev->mtu             = 1000;
313	dev->addr_len        = 0;
314}
315
316/*
317 *	Setup a new device.
318 */
319static int lapbeth_new_device(struct net_device *dev)
320{
321	struct net_device *ndev;
322	struct lapbethdev *lapbeth;
323	int rc = -ENOMEM;
324
325	ASSERT_RTNL();
326
327	ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d", NET_NAME_UNKNOWN,
328			    lapbeth_setup);
329	if (!ndev)
330		goto out;
331
332	lapbeth = netdev_priv(ndev);
333	lapbeth->axdev = ndev;
334
335	dev_hold(dev);
336	lapbeth->ethdev = dev;
337
338	rc = -EIO;
339	if (register_netdevice(ndev))
340		goto fail;
341
342	list_add_rcu(&lapbeth->node, &lapbeth_devices);
343	rc = 0;
344out:
345	return rc;
346fail:
347	dev_put(dev);
348	free_netdev(ndev);
349	kfree(lapbeth);
350	goto out;
351}
352
353/*
354 *	Free a lapb network device.
355 */
356static void lapbeth_free_device(struct lapbethdev *lapbeth)
357{
358	dev_put(lapbeth->ethdev);
359	list_del_rcu(&lapbeth->node);
360	unregister_netdevice(lapbeth->axdev);
361}
362
363/*
364 *	Handle device status changes.
365 *
366 * Called from notifier with RTNL held.
367 */
368static int lapbeth_device_event(struct notifier_block *this,
369				unsigned long event, void *ptr)
370{
371	struct lapbethdev *lapbeth;
372	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
373
374	if (dev_net(dev) != &init_net)
375		return NOTIFY_DONE;
376
377	if (!dev_is_ethdev(dev))
378		return NOTIFY_DONE;
379
380	switch (event) {
381	case NETDEV_UP:
382		/* New ethernet device -> new LAPB interface	 */
383		if (lapbeth_get_x25_dev(dev) == NULL)
384			lapbeth_new_device(dev);
385		break;
386	case NETDEV_DOWN:	
387		/* ethernet device closed -> close LAPB interface */
388		lapbeth = lapbeth_get_x25_dev(dev);
389		if (lapbeth) 
390			dev_close(lapbeth->axdev);
391		break;
392	case NETDEV_UNREGISTER:
393		/* ethernet device disappears -> remove LAPB interface */
394		lapbeth = lapbeth_get_x25_dev(dev);
395		if (lapbeth)
396			lapbeth_free_device(lapbeth);
397		break;
398	}
399
400	return NOTIFY_DONE;
401}
402
403/* ------------------------------------------------------------------------ */
404
405static struct packet_type lapbeth_packet_type __read_mostly = {
406	.type = cpu_to_be16(ETH_P_DEC),
407	.func = lapbeth_rcv,
408};
409
410static struct notifier_block lapbeth_dev_notifier = {
411	.notifier_call = lapbeth_device_event,
412};
413
414static const char banner[] __initconst =
415	KERN_INFO "LAPB Ethernet driver version 0.02\n";
416
417static int __init lapbeth_init_driver(void)
418{
419	dev_add_pack(&lapbeth_packet_type);
420
421	register_netdevice_notifier(&lapbeth_dev_notifier);
422
423	printk(banner);
424
425	return 0;
426}
427module_init(lapbeth_init_driver);
428
429static void __exit lapbeth_cleanup_driver(void)
430{
431	struct lapbethdev *lapbeth;
432	struct list_head *entry, *tmp;
433
434	dev_remove_pack(&lapbeth_packet_type);
435	unregister_netdevice_notifier(&lapbeth_dev_notifier);
436
437	rtnl_lock();
438	list_for_each_safe(entry, tmp, &lapbeth_devices) {
439		lapbeth = list_entry(entry, struct lapbethdev, node);
440
441		dev_put(lapbeth->ethdev);
442		unregister_netdevice(lapbeth->axdev);
443	}
444	rtnl_unlock();
445}
446module_exit(lapbeth_cleanup_driver);
447
448MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
449MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
450MODULE_LICENSE("GPL");
v3.1
  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
 23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 24
 25#include <linux/errno.h>
 26#include <linux/types.h>
 27#include <linux/socket.h>
 28#include <linux/in.h>
 29#include <linux/slab.h>
 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>
 38#include <asm/system.h>
 39#include <asm/uaccess.h>
 40#include <linux/mm.h>
 41#include <linux/interrupt.h>
 42#include <linux/notifier.h>
 43#include <linux/stat.h>
 44#include <linux/netfilter.h>
 45#include <linux/module.h>
 46#include <linux/lapb.h>
 47#include <linux/init.h>
 48
 49#include <net/x25device.h>
 50
 51static const u8 bcast_addr[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
 52
 53/* If this number is made larger, check that the temporary string buffer
 54 * in lapbeth_new_device is large enough to store the probe device name.*/
 55#define MAXLAPBDEV 100
 56
 57struct lapbethdev {
 58	struct list_head	node;
 59	struct net_device	*ethdev;	/* link to ethernet device */
 60	struct net_device	*axdev;		/* lapbeth device (lapb#) */
 61};
 62
 63static LIST_HEAD(lapbeth_devices);
 64
 65/* ------------------------------------------------------------------------ */
 66
 67/*
 68 *	Get the LAPB device for the ethernet device
 69 */
 70static struct lapbethdev *lapbeth_get_x25_dev(struct net_device *dev)
 71{
 72	struct lapbethdev *lapbeth;
 73
 74	list_for_each_entry_rcu(lapbeth, &lapbeth_devices, node) {
 75		if (lapbeth->ethdev == dev) 
 76			return lapbeth;
 77	}
 78	return NULL;
 79}
 80
 81static __inline__ int dev_is_ethdev(struct net_device *dev)
 82{
 83	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
 84}
 85
 86/* ------------------------------------------------------------------------ */
 87
 88/*
 89 *	Receive a LAPB frame via an ethernet interface.
 90 */
 91static int lapbeth_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
 92{
 93	int len, err;
 94	struct lapbethdev *lapbeth;
 95
 96	if (dev_net(dev) != &init_net)
 97		goto drop;
 98
 99	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
100		return NET_RX_DROP;
101
102	if (!pskb_may_pull(skb, 2))
103		goto drop;
104
105	rcu_read_lock();
106	lapbeth = lapbeth_get_x25_dev(dev);
107	if (!lapbeth)
108		goto drop_unlock;
109	if (!netif_running(lapbeth->axdev))
110		goto drop_unlock;
111
112	len = skb->data[0] + skb->data[1] * 256;
113	dev->stats.rx_packets++;
114	dev->stats.rx_bytes += len;
115
116	skb_pull(skb, 2);	/* Remove the length bytes */
117	skb_trim(skb, len);	/* Set the length of the data */
118
119	if ((err = lapb_data_received(lapbeth->axdev, skb)) != LAPB_OK) {
120		printk(KERN_DEBUG "lapbether: lapb_data_received err - %d\n", err);
121		goto drop_unlock;
122	}
123out:
124	rcu_read_unlock();
125	return 0;
126drop_unlock:
127	kfree_skb(skb);
128	goto out;
129drop:
130	kfree_skb(skb);
131	return 0;
132}
133
134static int lapbeth_data_indication(struct net_device *dev, struct sk_buff *skb)
135{
136	unsigned char *ptr;
137
138	skb_push(skb, 1);
139
140	if (skb_cow(skb, 1))
141		return NET_RX_DROP;
142
143	ptr  = skb->data;
144	*ptr = X25_IFACE_DATA;
145
146	skb->protocol = x25_type_trans(skb, dev);
147	return netif_rx(skb);
148}
149
150/*
151 *	Send a LAPB frame via an ethernet interface
152 */
153static netdev_tx_t lapbeth_xmit(struct sk_buff *skb,
154				      struct net_device *dev)
155{
156	int err;
157
158	/*
159	 * Just to be *really* sure not to send anything if the interface
160	 * is down, the ethernet device may have gone.
161	 */
162	if (!netif_running(dev))
163		goto drop;
164
165	switch (skb->data[0]) {
166	case X25_IFACE_DATA:
167		break;
168	case X25_IFACE_CONNECT:
169		if ((err = lapb_connect_request(dev)) != LAPB_OK)
170			pr_err("lapb_connect_request error: %d\n", err);
171		goto drop;
172	case X25_IFACE_DISCONNECT:
173		if ((err = lapb_disconnect_request(dev)) != LAPB_OK)
174			pr_err("lapb_disconnect_request err: %d\n", err);
175		/* Fall thru */
176	default:
177		goto drop;
178	}
179
180	skb_pull(skb, 1);
181
182	if ((err = lapb_data_request(dev, skb)) != LAPB_OK) {
183		pr_err("lapb_data_request error - %d\n", err);
184		goto drop;
185	}
186out:
187	return NETDEV_TX_OK;
188drop:
189	kfree_skb(skb);
190	goto out;
191}
192
193static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb)
194{
195	struct lapbethdev *lapbeth = netdev_priv(ndev);
196	unsigned char *ptr;
197	struct net_device *dev;
198	int size = skb->len;
199
200	skb->protocol = htons(ETH_P_X25);
201
202	ptr = skb_push(skb, 2);
203
204	*ptr++ = size % 256;
205	*ptr++ = size / 256;
206
207	ndev->stats.tx_packets++;
208	ndev->stats.tx_bytes += size;
209
210	skb->dev = dev = lapbeth->ethdev;
211
212	dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);
213
214	dev_queue_xmit(skb);
215}
216
217static void lapbeth_connected(struct net_device *dev, int reason)
218{
219	unsigned char *ptr;
220	struct sk_buff *skb = dev_alloc_skb(1);
221
222	if (!skb) {
223		pr_err("out of memory\n");
224		return;
225	}
226
227	ptr  = skb_put(skb, 1);
228	*ptr = X25_IFACE_CONNECT;
229
230	skb->protocol = x25_type_trans(skb, dev);
231	netif_rx(skb);
232}
233
234static void lapbeth_disconnected(struct net_device *dev, int reason)
235{
236	unsigned char *ptr;
237	struct sk_buff *skb = dev_alloc_skb(1);
238
239	if (!skb) {
240		pr_err("out of memory\n");
241		return;
242	}
243
244	ptr  = skb_put(skb, 1);
245	*ptr = X25_IFACE_DISCONNECT;
246
247	skb->protocol = x25_type_trans(skb, dev);
248	netif_rx(skb);
249}
250
251/*
252 *	Set AX.25 callsign
253 */
254static int lapbeth_set_mac_address(struct net_device *dev, void *addr)
255{
256	struct sockaddr *sa = addr;
257	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
258	return 0;
259}
260
261
262static struct lapb_register_struct lapbeth_callbacks = {
263	.connect_confirmation    = lapbeth_connected,
264	.connect_indication      = lapbeth_connected,
265	.disconnect_confirmation = lapbeth_disconnected,
266	.disconnect_indication   = lapbeth_disconnected,
267	.data_indication         = lapbeth_data_indication,
268	.data_transmit           = lapbeth_data_transmit,
269
270};
271
272/*
273 * open/close a device
274 */
275static int lapbeth_open(struct net_device *dev)
276{
277	int err;
278
279	if ((err = lapb_register(dev, &lapbeth_callbacks)) != LAPB_OK) {
280		pr_err("lapb_register error: %d\n", err);
281		return -ENODEV;
282	}
283
284	netif_start_queue(dev);
285	return 0;
286}
287
288static int lapbeth_close(struct net_device *dev)
289{
290	int err;
291
292	netif_stop_queue(dev);
293
294	if ((err = lapb_unregister(dev)) != LAPB_OK)
295		pr_err("lapb_unregister error: %d\n", err);
296
297	return 0;
298}
299
300/* ------------------------------------------------------------------------ */
301
302static const struct net_device_ops lapbeth_netdev_ops = {
303	.ndo_open	     = lapbeth_open,
304	.ndo_stop	     = lapbeth_close,
305	.ndo_start_xmit	     = lapbeth_xmit,
306	.ndo_set_mac_address = lapbeth_set_mac_address,
307};
308
309static void lapbeth_setup(struct net_device *dev)
310{
311	dev->netdev_ops	     = &lapbeth_netdev_ops;
312	dev->destructor	     = free_netdev;
313	dev->type            = ARPHRD_X25;
314	dev->hard_header_len = 3;
315	dev->mtu             = 1000;
316	dev->addr_len        = 0;
317}
318
319/*
320 *	Setup a new device.
321 */
322static int lapbeth_new_device(struct net_device *dev)
323{
324	struct net_device *ndev;
325	struct lapbethdev *lapbeth;
326	int rc = -ENOMEM;
327
328	ASSERT_RTNL();
329
330	ndev = alloc_netdev(sizeof(*lapbeth), "lapb%d", 
331			   lapbeth_setup);
332	if (!ndev)
333		goto out;
334
335	lapbeth = netdev_priv(ndev);
336	lapbeth->axdev = ndev;
337
338	dev_hold(dev);
339	lapbeth->ethdev = dev;
340
341	rc = -EIO;
342	if (register_netdevice(ndev))
343		goto fail;
344
345	list_add_rcu(&lapbeth->node, &lapbeth_devices);
346	rc = 0;
347out:
348	return rc;
349fail:
350	dev_put(dev);
351	free_netdev(ndev);
352	kfree(lapbeth);
353	goto out;
354}
355
356/*
357 *	Free a lapb network device.
358 */
359static void lapbeth_free_device(struct lapbethdev *lapbeth)
360{
361	dev_put(lapbeth->ethdev);
362	list_del_rcu(&lapbeth->node);
363	unregister_netdevice(lapbeth->axdev);
364}
365
366/*
367 *	Handle device status changes.
368 *
369 * Called from notifier with RTNL held.
370 */
371static int lapbeth_device_event(struct notifier_block *this,
372				unsigned long event, void *ptr)
373{
374	struct lapbethdev *lapbeth;
375	struct net_device *dev = ptr;
376
377	if (dev_net(dev) != &init_net)
378		return NOTIFY_DONE;
379
380	if (!dev_is_ethdev(dev))
381		return NOTIFY_DONE;
382
383	switch (event) {
384	case NETDEV_UP:
385		/* New ethernet device -> new LAPB interface	 */
386		if (lapbeth_get_x25_dev(dev) == NULL)
387			lapbeth_new_device(dev);
388		break;
389	case NETDEV_DOWN:	
390		/* ethernet device closed -> close LAPB interface */
391		lapbeth = lapbeth_get_x25_dev(dev);
392		if (lapbeth) 
393			dev_close(lapbeth->axdev);
394		break;
395	case NETDEV_UNREGISTER:
396		/* ethernet device disappears -> remove LAPB interface */
397		lapbeth = lapbeth_get_x25_dev(dev);
398		if (lapbeth)
399			lapbeth_free_device(lapbeth);
400		break;
401	}
402
403	return NOTIFY_DONE;
404}
405
406/* ------------------------------------------------------------------------ */
407
408static struct packet_type lapbeth_packet_type __read_mostly = {
409	.type = cpu_to_be16(ETH_P_DEC),
410	.func = lapbeth_rcv,
411};
412
413static struct notifier_block lapbeth_dev_notifier = {
414	.notifier_call = lapbeth_device_event,
415};
416
417static const char banner[] __initconst =
418	KERN_INFO "LAPB Ethernet driver version 0.02\n";
419
420static int __init lapbeth_init_driver(void)
421{
422	dev_add_pack(&lapbeth_packet_type);
423
424	register_netdevice_notifier(&lapbeth_dev_notifier);
425
426	printk(banner);
427
428	return 0;
429}
430module_init(lapbeth_init_driver);
431
432static void __exit lapbeth_cleanup_driver(void)
433{
434	struct lapbethdev *lapbeth;
435	struct list_head *entry, *tmp;
436
437	dev_remove_pack(&lapbeth_packet_type);
438	unregister_netdevice_notifier(&lapbeth_dev_notifier);
439
440	rtnl_lock();
441	list_for_each_safe(entry, tmp, &lapbeth_devices) {
442		lapbeth = list_entry(entry, struct lapbethdev, node);
443
444		dev_put(lapbeth->ethdev);
445		unregister_netdevice(lapbeth->axdev);
446	}
447	rtnl_unlock();
448}
449module_exit(lapbeth_cleanup_driver);
450
451MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
452MODULE_DESCRIPTION("The unofficial LAPB over Ethernet driver");
453MODULE_LICENSE("GPL");