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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
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
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
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
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;
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);
442
