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v4.6
 
  1/*
  2 *	LAPB release 002
  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 *	History
 13 *	LAPB 001	Jonathan Naylor	Started Coding
 14 *	LAPB 002	Jonathan Naylor	New timer architecture.
 15 *	2000-10-29	Henner Eisen	lapb_data_indication() return status.
 16 */
 17
 18#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 19
 20#include <linux/module.h>
 21#include <linux/errno.h>
 22#include <linux/types.h>
 23#include <linux/socket.h>
 24#include <linux/in.h>
 25#include <linux/kernel.h>
 26#include <linux/jiffies.h>
 27#include <linux/timer.h>
 28#include <linux/string.h>
 29#include <linux/sockios.h>
 30#include <linux/net.h>
 31#include <linux/inet.h>
 32#include <linux/if_arp.h>
 33#include <linux/skbuff.h>
 34#include <linux/slab.h>
 35#include <net/sock.h>
 36#include <asm/uaccess.h>
 37#include <linux/fcntl.h>
 38#include <linux/mm.h>
 39#include <linux/interrupt.h>
 40#include <linux/stat.h>
 41#include <linux/init.h>
 42#include <net/lapb.h>
 43
 44static LIST_HEAD(lapb_list);
 45static DEFINE_RWLOCK(lapb_list_lock);
 46
 47/*
 48 *	Free an allocated lapb control block.
 49 */
 50static void lapb_free_cb(struct lapb_cb *lapb)
 51{
 52	kfree(lapb);
 53}
 54
 55static __inline__ void lapb_hold(struct lapb_cb *lapb)
 56{
 57	atomic_inc(&lapb->refcnt);
 58}
 59
 60static __inline__ void lapb_put(struct lapb_cb *lapb)
 61{
 62	if (atomic_dec_and_test(&lapb->refcnt))
 63		lapb_free_cb(lapb);
 64}
 65
 66/*
 67 *	Socket removal during an interrupt is now safe.
 68 */
 69static void __lapb_remove_cb(struct lapb_cb *lapb)
 70{
 71	if (lapb->node.next) {
 72		list_del(&lapb->node);
 73		lapb_put(lapb);
 74	}
 75}
 76EXPORT_SYMBOL(lapb_register);
 77
 78/*
 79 *	Add a socket to the bound sockets list.
 80 */
 81static void __lapb_insert_cb(struct lapb_cb *lapb)
 82{
 83	list_add(&lapb->node, &lapb_list);
 84	lapb_hold(lapb);
 85}
 86
 87static struct lapb_cb *__lapb_devtostruct(struct net_device *dev)
 88{
 89	struct list_head *entry;
 90	struct lapb_cb *lapb, *use = NULL;
 91
 92	list_for_each(entry, &lapb_list) {
 93		lapb = list_entry(entry, struct lapb_cb, node);
 94		if (lapb->dev == dev) {
 95			use = lapb;
 96			break;
 97		}
 98	}
 99
100	if (use)
101		lapb_hold(use);
102
103	return use;
104}
105
106static struct lapb_cb *lapb_devtostruct(struct net_device *dev)
107{
108	struct lapb_cb *rc;
109
110	read_lock_bh(&lapb_list_lock);
111	rc = __lapb_devtostruct(dev);
112	read_unlock_bh(&lapb_list_lock);
113
114	return rc;
115}
116/*
117 *	Create an empty LAPB control block.
118 */
119static struct lapb_cb *lapb_create_cb(void)
120{
121	struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC);
122
123
124	if (!lapb)
125		goto out;
126
127	skb_queue_head_init(&lapb->write_queue);
128	skb_queue_head_init(&lapb->ack_queue);
129
130	init_timer(&lapb->t1timer);
131	init_timer(&lapb->t2timer);
132
133	lapb->t1      = LAPB_DEFAULT_T1;
134	lapb->t2      = LAPB_DEFAULT_T2;
135	lapb->n2      = LAPB_DEFAULT_N2;
136	lapb->mode    = LAPB_DEFAULT_MODE;
137	lapb->window  = LAPB_DEFAULT_WINDOW;
138	lapb->state   = LAPB_STATE_0;
139	atomic_set(&lapb->refcnt, 1);
140out:
141	return lapb;
142}
143
144int lapb_register(struct net_device *dev,
145		  const struct lapb_register_struct *callbacks)
146{
147	struct lapb_cb *lapb;
148	int rc = LAPB_BADTOKEN;
149
150	write_lock_bh(&lapb_list_lock);
151
152	lapb = __lapb_devtostruct(dev);
153	if (lapb) {
154		lapb_put(lapb);
155		goto out;
156	}
157
158	lapb = lapb_create_cb();
159	rc = LAPB_NOMEM;
160	if (!lapb)
161		goto out;
162
163	lapb->dev       = dev;
164	lapb->callbacks = callbacks;
165
166	__lapb_insert_cb(lapb);
167
168	lapb_start_t1timer(lapb);
169
170	rc = LAPB_OK;
171out:
172	write_unlock_bh(&lapb_list_lock);
173	return rc;
174}
 
175
176int lapb_unregister(struct net_device *dev)
177{
178	struct lapb_cb *lapb;
179	int rc = LAPB_BADTOKEN;
180
181	write_lock_bh(&lapb_list_lock);
182	lapb = __lapb_devtostruct(dev);
183	if (!lapb)
184		goto out;
 
185
186	lapb_stop_t1timer(lapb);
187	lapb_stop_t2timer(lapb);
188
189	lapb_clear_queues(lapb);
190
191	__lapb_remove_cb(lapb);
192
193	lapb_put(lapb);
194	rc = LAPB_OK;
195out:
196	write_unlock_bh(&lapb_list_lock);
197	return rc;
198}
199EXPORT_SYMBOL(lapb_unregister);
200
201int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms)
202{
203	int rc = LAPB_BADTOKEN;
204	struct lapb_cb *lapb = lapb_devtostruct(dev);
205
206	if (!lapb)
207		goto out;
208
209	parms->t1      = lapb->t1 / HZ;
210	parms->t2      = lapb->t2 / HZ;
211	parms->n2      = lapb->n2;
212	parms->n2count = lapb->n2count;
213	parms->state   = lapb->state;
214	parms->window  = lapb->window;
215	parms->mode    = lapb->mode;
216
217	if (!timer_pending(&lapb->t1timer))
218		parms->t1timer = 0;
219	else
220		parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;
221
222	if (!timer_pending(&lapb->t2timer))
223		parms->t2timer = 0;
224	else
225		parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;
226
227	lapb_put(lapb);
228	rc = LAPB_OK;
229out:
230	return rc;
231}
232EXPORT_SYMBOL(lapb_getparms);
233
234int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms)
235{
236	int rc = LAPB_BADTOKEN;
237	struct lapb_cb *lapb = lapb_devtostruct(dev);
238
239	if (!lapb)
240		goto out;
241
242	rc = LAPB_INVALUE;
243	if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1)
244		goto out_put;
245
246	if (lapb->state == LAPB_STATE_0) {
247		if (parms->mode & LAPB_EXTENDED) {
248			if (parms->window < 1 || parms->window > 127)
249				goto out_put;
250		} else {
251			if (parms->window < 1 || parms->window > 7)
252				goto out_put;
253		}
254		lapb->mode    = parms->mode;
255		lapb->window  = parms->window;
256	}
257
258	lapb->t1    = parms->t1 * HZ;
259	lapb->t2    = parms->t2 * HZ;
260	lapb->n2    = parms->n2;
261
262	rc = LAPB_OK;
263out_put:
264	lapb_put(lapb);
265out:
266	return rc;
267}
268EXPORT_SYMBOL(lapb_setparms);
269
270int lapb_connect_request(struct net_device *dev)
271{
272	struct lapb_cb *lapb = lapb_devtostruct(dev);
273	int rc = LAPB_BADTOKEN;
274
275	if (!lapb)
276		goto out;
277
278	rc = LAPB_OK;
279	if (lapb->state == LAPB_STATE_1)
280		goto out_put;
281
282	rc = LAPB_CONNECTED;
283	if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4)
284		goto out_put;
285
286	lapb_establish_data_link(lapb);
287
288	lapb_dbg(0, "(%p) S0 -> S1\n", lapb->dev);
289	lapb->state = LAPB_STATE_1;
290
291	rc = LAPB_OK;
292out_put:
293	lapb_put(lapb);
294out:
295	return rc;
296}
297EXPORT_SYMBOL(lapb_connect_request);
298
299int lapb_disconnect_request(struct net_device *dev)
300{
301	struct lapb_cb *lapb = lapb_devtostruct(dev);
302	int rc = LAPB_BADTOKEN;
303
304	if (!lapb)
305		goto out;
306
307	switch (lapb->state) {
308	case LAPB_STATE_0:
309		rc = LAPB_NOTCONNECTED;
310		goto out_put;
311
312	case LAPB_STATE_1:
313		lapb_dbg(1, "(%p) S1 TX DISC(1)\n", lapb->dev);
314		lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
315		lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
316		lapb->state = LAPB_STATE_0;
317		lapb_start_t1timer(lapb);
318		rc = LAPB_NOTCONNECTED;
319		goto out_put;
320
321	case LAPB_STATE_2:
322		rc = LAPB_OK;
323		goto out_put;
324	}
325
326	lapb_clear_queues(lapb);
327	lapb->n2count = 0;
328	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
329	lapb_start_t1timer(lapb);
330	lapb_stop_t2timer(lapb);
331	lapb->state = LAPB_STATE_2;
332
333	lapb_dbg(1, "(%p) S3 DISC(1)\n", lapb->dev);
334	lapb_dbg(0, "(%p) S3 -> S2\n", lapb->dev);
335
336	rc = LAPB_OK;
337out_put:
338	lapb_put(lapb);
339out:
340	return rc;
341}
342EXPORT_SYMBOL(lapb_disconnect_request);
343
344int lapb_data_request(struct net_device *dev, struct sk_buff *skb)
345{
346	struct lapb_cb *lapb = lapb_devtostruct(dev);
347	int rc = LAPB_BADTOKEN;
348
349	if (!lapb)
350		goto out;
351
352	rc = LAPB_NOTCONNECTED;
353	if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
354		goto out_put;
355
356	skb_queue_tail(&lapb->write_queue, skb);
357	lapb_kick(lapb);
358	rc = LAPB_OK;
359out_put:
360	lapb_put(lapb);
361out:
362	return rc;
363}
364EXPORT_SYMBOL(lapb_data_request);
365
366int lapb_data_received(struct net_device *dev, struct sk_buff *skb)
367{
368	struct lapb_cb *lapb = lapb_devtostruct(dev);
369	int rc = LAPB_BADTOKEN;
370
371	if (lapb) {
372		lapb_data_input(lapb, skb);
373		lapb_put(lapb);
374		rc = LAPB_OK;
375	}
376
377	return rc;
378}
379EXPORT_SYMBOL(lapb_data_received);
380
381void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
382{
383	if (lapb->callbacks->connect_confirmation)
384		lapb->callbacks->connect_confirmation(lapb->dev, reason);
385}
386
387void lapb_connect_indication(struct lapb_cb *lapb, int reason)
388{
389	if (lapb->callbacks->connect_indication)
390		lapb->callbacks->connect_indication(lapb->dev, reason);
391}
392
393void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
394{
395	if (lapb->callbacks->disconnect_confirmation)
396		lapb->callbacks->disconnect_confirmation(lapb->dev, reason);
397}
398
399void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
400{
401	if (lapb->callbacks->disconnect_indication)
402		lapb->callbacks->disconnect_indication(lapb->dev, reason);
403}
404
405int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb)
406{
407	if (lapb->callbacks->data_indication)
408		return lapb->callbacks->data_indication(lapb->dev, skb);
409
410	kfree_skb(skb);
411	return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
412}
413
414int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb)
415{
416	int used = 0;
417
418	if (lapb->callbacks->data_transmit) {
419		lapb->callbacks->data_transmit(lapb->dev, skb);
420		used = 1;
421	}
422
423	return used;
424}
425
426static int __init lapb_init(void)
427{
428	return 0;
429}
430
431static void __exit lapb_exit(void)
432{
433	WARN_ON(!list_empty(&lapb_list));
434}
435
436MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
437MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
438MODULE_LICENSE("GPL");
439
440module_init(lapb_init);
441module_exit(lapb_exit);
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *	LAPB release 002
  4 *
  5 *	This code REQUIRES 2.1.15 or higher/ NET3.038
  6 *
 
 
 
 
 
 
  7 *	History
  8 *	LAPB 001	Jonathan Naylor	Started Coding
  9 *	LAPB 002	Jonathan Naylor	New timer architecture.
 10 *	2000-10-29	Henner Eisen	lapb_data_indication() return status.
 11 */
 12
 13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 14
 15#include <linux/module.h>
 16#include <linux/errno.h>
 17#include <linux/types.h>
 18#include <linux/socket.h>
 19#include <linux/in.h>
 20#include <linux/kernel.h>
 21#include <linux/jiffies.h>
 22#include <linux/timer.h>
 23#include <linux/string.h>
 24#include <linux/sockios.h>
 25#include <linux/net.h>
 26#include <linux/inet.h>
 27#include <linux/if_arp.h>
 28#include <linux/skbuff.h>
 29#include <linux/slab.h>
 30#include <net/sock.h>
 31#include <linux/uaccess.h>
 32#include <linux/fcntl.h>
 33#include <linux/mm.h>
 34#include <linux/interrupt.h>
 35#include <linux/stat.h>
 36#include <linux/init.h>
 37#include <net/lapb.h>
 38
 39static LIST_HEAD(lapb_list);
 40static DEFINE_RWLOCK(lapb_list_lock);
 41
 42/*
 43 *	Free an allocated lapb control block.
 44 */
 45static void lapb_free_cb(struct lapb_cb *lapb)
 46{
 47	kfree(lapb);
 48}
 49
 50static __inline__ void lapb_hold(struct lapb_cb *lapb)
 51{
 52	refcount_inc(&lapb->refcnt);
 53}
 54
 55static __inline__ void lapb_put(struct lapb_cb *lapb)
 56{
 57	if (refcount_dec_and_test(&lapb->refcnt))
 58		lapb_free_cb(lapb);
 59}
 60
 61/*
 62 *	Socket removal during an interrupt is now safe.
 63 */
 64static void __lapb_remove_cb(struct lapb_cb *lapb)
 65{
 66	if (lapb->node.next) {
 67		list_del(&lapb->node);
 68		lapb_put(lapb);
 69	}
 70}
 
 71
 72/*
 73 *	Add a socket to the bound sockets list.
 74 */
 75static void __lapb_insert_cb(struct lapb_cb *lapb)
 76{
 77	list_add(&lapb->node, &lapb_list);
 78	lapb_hold(lapb);
 79}
 80
 81static struct lapb_cb *__lapb_devtostruct(struct net_device *dev)
 82{
 83	struct list_head *entry;
 84	struct lapb_cb *lapb, *use = NULL;
 85
 86	list_for_each(entry, &lapb_list) {
 87		lapb = list_entry(entry, struct lapb_cb, node);
 88		if (lapb->dev == dev) {
 89			use = lapb;
 90			break;
 91		}
 92	}
 93
 94	if (use)
 95		lapb_hold(use);
 96
 97	return use;
 98}
 99
100static struct lapb_cb *lapb_devtostruct(struct net_device *dev)
101{
102	struct lapb_cb *rc;
103
104	read_lock_bh(&lapb_list_lock);
105	rc = __lapb_devtostruct(dev);
106	read_unlock_bh(&lapb_list_lock);
107
108	return rc;
109}
110/*
111 *	Create an empty LAPB control block.
112 */
113static struct lapb_cb *lapb_create_cb(void)
114{
115	struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC);
116
 
117	if (!lapb)
118		goto out;
119
120	skb_queue_head_init(&lapb->write_queue);
121	skb_queue_head_init(&lapb->ack_queue);
122
123	timer_setup(&lapb->t1timer, NULL, 0);
124	timer_setup(&lapb->t2timer, NULL, 0);
125
126	lapb->t1      = LAPB_DEFAULT_T1;
127	lapb->t2      = LAPB_DEFAULT_T2;
128	lapb->n2      = LAPB_DEFAULT_N2;
129	lapb->mode    = LAPB_DEFAULT_MODE;
130	lapb->window  = LAPB_DEFAULT_WINDOW;
131	lapb->state   = LAPB_STATE_0;
132	refcount_set(&lapb->refcnt, 1);
133out:
134	return lapb;
135}
136
137int lapb_register(struct net_device *dev,
138		  const struct lapb_register_struct *callbacks)
139{
140	struct lapb_cb *lapb;
141	int rc = LAPB_BADTOKEN;
142
143	write_lock_bh(&lapb_list_lock);
144
145	lapb = __lapb_devtostruct(dev);
146	if (lapb) {
147		lapb_put(lapb);
148		goto out;
149	}
150
151	lapb = lapb_create_cb();
152	rc = LAPB_NOMEM;
153	if (!lapb)
154		goto out;
155
156	lapb->dev       = dev;
157	lapb->callbacks = callbacks;
158
159	__lapb_insert_cb(lapb);
160
161	lapb_start_t1timer(lapb);
162
163	rc = LAPB_OK;
164out:
165	write_unlock_bh(&lapb_list_lock);
166	return rc;
167}
168EXPORT_SYMBOL(lapb_register);
169
170int lapb_unregister(struct net_device *dev)
171{
172	struct lapb_cb *lapb;
173	int rc = LAPB_BADTOKEN;
174
175	write_lock_bh(&lapb_list_lock);
176	lapb = __lapb_devtostruct(dev);
177	if (!lapb)
178		goto out;
179	lapb_put(lapb);
180
181	lapb_stop_t1timer(lapb);
182	lapb_stop_t2timer(lapb);
183
184	lapb_clear_queues(lapb);
185
186	__lapb_remove_cb(lapb);
187
188	lapb_put(lapb);
189	rc = LAPB_OK;
190out:
191	write_unlock_bh(&lapb_list_lock);
192	return rc;
193}
194EXPORT_SYMBOL(lapb_unregister);
195
196int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms)
197{
198	int rc = LAPB_BADTOKEN;
199	struct lapb_cb *lapb = lapb_devtostruct(dev);
200
201	if (!lapb)
202		goto out;
203
204	parms->t1      = lapb->t1 / HZ;
205	parms->t2      = lapb->t2 / HZ;
206	parms->n2      = lapb->n2;
207	parms->n2count = lapb->n2count;
208	parms->state   = lapb->state;
209	parms->window  = lapb->window;
210	parms->mode    = lapb->mode;
211
212	if (!timer_pending(&lapb->t1timer))
213		parms->t1timer = 0;
214	else
215		parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;
216
217	if (!timer_pending(&lapb->t2timer))
218		parms->t2timer = 0;
219	else
220		parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;
221
222	lapb_put(lapb);
223	rc = LAPB_OK;
224out:
225	return rc;
226}
227EXPORT_SYMBOL(lapb_getparms);
228
229int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms)
230{
231	int rc = LAPB_BADTOKEN;
232	struct lapb_cb *lapb = lapb_devtostruct(dev);
233
234	if (!lapb)
235		goto out;
236
237	rc = LAPB_INVALUE;
238	if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1)
239		goto out_put;
240
241	if (lapb->state == LAPB_STATE_0) {
242		if (parms->mode & LAPB_EXTENDED) {
243			if (parms->window < 1 || parms->window > 127)
244				goto out_put;
245		} else {
246			if (parms->window < 1 || parms->window > 7)
247				goto out_put;
248		}
249		lapb->mode    = parms->mode;
250		lapb->window  = parms->window;
251	}
252
253	lapb->t1    = parms->t1 * HZ;
254	lapb->t2    = parms->t2 * HZ;
255	lapb->n2    = parms->n2;
256
257	rc = LAPB_OK;
258out_put:
259	lapb_put(lapb);
260out:
261	return rc;
262}
263EXPORT_SYMBOL(lapb_setparms);
264
265int lapb_connect_request(struct net_device *dev)
266{
267	struct lapb_cb *lapb = lapb_devtostruct(dev);
268	int rc = LAPB_BADTOKEN;
269
270	if (!lapb)
271		goto out;
272
273	rc = LAPB_OK;
274	if (lapb->state == LAPB_STATE_1)
275		goto out_put;
276
277	rc = LAPB_CONNECTED;
278	if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4)
279		goto out_put;
280
281	lapb_establish_data_link(lapb);
282
283	lapb_dbg(0, "(%p) S0 -> S1\n", lapb->dev);
284	lapb->state = LAPB_STATE_1;
285
286	rc = LAPB_OK;
287out_put:
288	lapb_put(lapb);
289out:
290	return rc;
291}
292EXPORT_SYMBOL(lapb_connect_request);
293
294int lapb_disconnect_request(struct net_device *dev)
295{
296	struct lapb_cb *lapb = lapb_devtostruct(dev);
297	int rc = LAPB_BADTOKEN;
298
299	if (!lapb)
300		goto out;
301
302	switch (lapb->state) {
303	case LAPB_STATE_0:
304		rc = LAPB_NOTCONNECTED;
305		goto out_put;
306
307	case LAPB_STATE_1:
308		lapb_dbg(1, "(%p) S1 TX DISC(1)\n", lapb->dev);
309		lapb_dbg(0, "(%p) S1 -> S0\n", lapb->dev);
310		lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
311		lapb->state = LAPB_STATE_0;
312		lapb_start_t1timer(lapb);
313		rc = LAPB_NOTCONNECTED;
314		goto out_put;
315
316	case LAPB_STATE_2:
317		rc = LAPB_OK;
318		goto out_put;
319	}
320
321	lapb_clear_queues(lapb);
322	lapb->n2count = 0;
323	lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
324	lapb_start_t1timer(lapb);
325	lapb_stop_t2timer(lapb);
326	lapb->state = LAPB_STATE_2;
327
328	lapb_dbg(1, "(%p) S3 DISC(1)\n", lapb->dev);
329	lapb_dbg(0, "(%p) S3 -> S2\n", lapb->dev);
330
331	rc = LAPB_OK;
332out_put:
333	lapb_put(lapb);
334out:
335	return rc;
336}
337EXPORT_SYMBOL(lapb_disconnect_request);
338
339int lapb_data_request(struct net_device *dev, struct sk_buff *skb)
340{
341	struct lapb_cb *lapb = lapb_devtostruct(dev);
342	int rc = LAPB_BADTOKEN;
343
344	if (!lapb)
345		goto out;
346
347	rc = LAPB_NOTCONNECTED;
348	if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
349		goto out_put;
350
351	skb_queue_tail(&lapb->write_queue, skb);
352	lapb_kick(lapb);
353	rc = LAPB_OK;
354out_put:
355	lapb_put(lapb);
356out:
357	return rc;
358}
359EXPORT_SYMBOL(lapb_data_request);
360
361int lapb_data_received(struct net_device *dev, struct sk_buff *skb)
362{
363	struct lapb_cb *lapb = lapb_devtostruct(dev);
364	int rc = LAPB_BADTOKEN;
365
366	if (lapb) {
367		lapb_data_input(lapb, skb);
368		lapb_put(lapb);
369		rc = LAPB_OK;
370	}
371
372	return rc;
373}
374EXPORT_SYMBOL(lapb_data_received);
375
376void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
377{
378	if (lapb->callbacks->connect_confirmation)
379		lapb->callbacks->connect_confirmation(lapb->dev, reason);
380}
381
382void lapb_connect_indication(struct lapb_cb *lapb, int reason)
383{
384	if (lapb->callbacks->connect_indication)
385		lapb->callbacks->connect_indication(lapb->dev, reason);
386}
387
388void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
389{
390	if (lapb->callbacks->disconnect_confirmation)
391		lapb->callbacks->disconnect_confirmation(lapb->dev, reason);
392}
393
394void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
395{
396	if (lapb->callbacks->disconnect_indication)
397		lapb->callbacks->disconnect_indication(lapb->dev, reason);
398}
399
400int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb)
401{
402	if (lapb->callbacks->data_indication)
403		return lapb->callbacks->data_indication(lapb->dev, skb);
404
405	kfree_skb(skb);
406	return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
407}
408
409int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb)
410{
411	int used = 0;
412
413	if (lapb->callbacks->data_transmit) {
414		lapb->callbacks->data_transmit(lapb->dev, skb);
415		used = 1;
416	}
417
418	return used;
419}
420
421static int __init lapb_init(void)
422{
423	return 0;
424}
425
426static void __exit lapb_exit(void)
427{
428	WARN_ON(!list_empty(&lapb_list));
429}
430
431MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
432MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
433MODULE_LICENSE("GPL");
434
435module_init(lapb_init);
436module_exit(lapb_exit);