Commit | Line | Data |
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1da177e4 LT |
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 | #include <linux/module.h> | |
19 | #include <linux/errno.h> | |
20 | #include <linux/types.h> | |
21 | #include <linux/socket.h> | |
22 | #include <linux/in.h> | |
23 | #include <linux/kernel.h> | |
24 | #include <linux/jiffies.h> | |
25 | #include <linux/timer.h> | |
26 | #include <linux/string.h> | |
27 | #include <linux/sockios.h> | |
28 | #include <linux/net.h> | |
29 | #include <linux/inet.h> | |
30 | #include <linux/if_arp.h> | |
31 | #include <linux/skbuff.h> | |
32 | #include <net/sock.h> | |
33 | #include <asm/uaccess.h> | |
34 | #include <asm/system.h> | |
35 | #include <linux/fcntl.h> | |
36 | #include <linux/mm.h> | |
37 | #include <linux/interrupt.h> | |
38 | #include <linux/stat.h> | |
39 | #include <linux/init.h> | |
40 | #include <net/lapb.h> | |
41 | ||
42 | static struct list_head lapb_list = LIST_HEAD_INIT(lapb_list); | |
43 | static DEFINE_RWLOCK(lapb_list_lock); | |
44 | ||
45 | /* | |
46 | * Free an allocated lapb control block. | |
47 | */ | |
48 | static void lapb_free_cb(struct lapb_cb *lapb) | |
49 | { | |
50 | kfree(lapb); | |
51 | } | |
52 | ||
53 | static __inline__ void lapb_hold(struct lapb_cb *lapb) | |
54 | { | |
55 | atomic_inc(&lapb->refcnt); | |
56 | } | |
57 | ||
58 | static __inline__ void lapb_put(struct lapb_cb *lapb) | |
59 | { | |
60 | if (atomic_dec_and_test(&lapb->refcnt)) | |
61 | lapb_free_cb(lapb); | |
62 | } | |
63 | ||
64 | /* | |
65 | * Socket removal during an interrupt is now safe. | |
66 | */ | |
67 | static void __lapb_remove_cb(struct lapb_cb *lapb) | |
68 | { | |
69 | if (lapb->node.next) { | |
70 | list_del(&lapb->node); | |
71 | lapb_put(lapb); | |
72 | } | |
73 | } | |
74 | ||
75 | /* | |
76 | * Add a socket to the bound sockets list. | |
77 | */ | |
78 | static void __lapb_insert_cb(struct lapb_cb *lapb) | |
79 | { | |
80 | list_add(&lapb->node, &lapb_list); | |
81 | lapb_hold(lapb); | |
82 | } | |
83 | ||
84 | static struct lapb_cb *__lapb_devtostruct(struct net_device *dev) | |
85 | { | |
86 | struct list_head *entry; | |
87 | struct lapb_cb *lapb, *use = NULL; | |
88 | ||
89 | list_for_each(entry, &lapb_list) { | |
90 | lapb = list_entry(entry, struct lapb_cb, node); | |
91 | if (lapb->dev == dev) { | |
92 | use = lapb; | |
93 | break; | |
94 | } | |
95 | } | |
96 | ||
97 | if (use) | |
98 | lapb_hold(use); | |
99 | ||
100 | return use; | |
101 | } | |
102 | ||
103 | static struct lapb_cb *lapb_devtostruct(struct net_device *dev) | |
104 | { | |
105 | struct lapb_cb *rc; | |
106 | ||
107 | read_lock_bh(&lapb_list_lock); | |
108 | rc = __lapb_devtostruct(dev); | |
109 | read_unlock_bh(&lapb_list_lock); | |
110 | ||
111 | return rc; | |
112 | } | |
113 | /* | |
114 | * Create an empty LAPB control block. | |
115 | */ | |
116 | static struct lapb_cb *lapb_create_cb(void) | |
117 | { | |
0da974f4 | 118 | struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC); |
1da177e4 LT |
119 | |
120 | ||
121 | if (!lapb) | |
122 | goto out; | |
123 | ||
1da177e4 LT |
124 | skb_queue_head_init(&lapb->write_queue); |
125 | skb_queue_head_init(&lapb->ack_queue); | |
126 | ||
127 | init_timer(&lapb->t1timer); | |
128 | init_timer(&lapb->t2timer); | |
129 | ||
130 | lapb->t1 = LAPB_DEFAULT_T1; | |
131 | lapb->t2 = LAPB_DEFAULT_T2; | |
132 | lapb->n2 = LAPB_DEFAULT_N2; | |
133 | lapb->mode = LAPB_DEFAULT_MODE; | |
134 | lapb->window = LAPB_DEFAULT_WINDOW; | |
135 | lapb->state = LAPB_STATE_0; | |
136 | atomic_set(&lapb->refcnt, 1); | |
137 | out: | |
138 | return lapb; | |
139 | } | |
140 | ||
141 | int lapb_register(struct net_device *dev, struct lapb_register_struct *callbacks) | |
142 | { | |
143 | struct lapb_cb *lapb; | |
144 | int rc = LAPB_BADTOKEN; | |
145 | ||
146 | write_lock_bh(&lapb_list_lock); | |
147 | ||
148 | lapb = __lapb_devtostruct(dev); | |
149 | if (lapb) { | |
150 | lapb_put(lapb); | |
151 | goto out; | |
152 | } | |
153 | ||
154 | lapb = lapb_create_cb(); | |
155 | rc = LAPB_NOMEM; | |
156 | if (!lapb) | |
157 | goto out; | |
158 | ||
159 | lapb->dev = dev; | |
160 | lapb->callbacks = *callbacks; | |
161 | ||
162 | __lapb_insert_cb(lapb); | |
163 | ||
164 | lapb_start_t1timer(lapb); | |
165 | ||
166 | rc = LAPB_OK; | |
167 | out: | |
168 | write_unlock_bh(&lapb_list_lock); | |
169 | return rc; | |
170 | } | |
171 | ||
172 | int lapb_unregister(struct net_device *dev) | |
173 | { | |
174 | struct lapb_cb *lapb; | |
175 | int rc = LAPB_BADTOKEN; | |
176 | ||
177 | write_lock_bh(&lapb_list_lock); | |
178 | lapb = __lapb_devtostruct(dev); | |
179 | if (!lapb) | |
180 | goto out; | |
181 | ||
182 | lapb_stop_t1timer(lapb); | |
183 | lapb_stop_t2timer(lapb); | |
184 | ||
185 | lapb_clear_queues(lapb); | |
186 | ||
187 | __lapb_remove_cb(lapb); | |
188 | ||
189 | lapb_put(lapb); | |
190 | rc = LAPB_OK; | |
191 | out: | |
192 | write_unlock_bh(&lapb_list_lock); | |
193 | return rc; | |
194 | } | |
195 | ||
196 | int 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; | |
224 | out: | |
225 | return rc; | |
226 | } | |
227 | ||
228 | int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms) | |
229 | { | |
230 | int rc = LAPB_BADTOKEN; | |
231 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
232 | ||
233 | if (!lapb) | |
234 | goto out; | |
235 | ||
236 | rc = LAPB_INVALUE; | |
237 | if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1) | |
238 | goto out_put; | |
239 | ||
240 | if (lapb->state == LAPB_STATE_0) { | |
241 | if (((parms->mode & LAPB_EXTENDED) && | |
242 | (parms->window < 1 || parms->window > 127)) || | |
243 | (parms->window < 1 || parms->window > 7)) | |
244 | goto out_put; | |
245 | ||
246 | lapb->mode = parms->mode; | |
247 | lapb->window = parms->window; | |
248 | } | |
249 | ||
250 | lapb->t1 = parms->t1 * HZ; | |
251 | lapb->t2 = parms->t2 * HZ; | |
252 | lapb->n2 = parms->n2; | |
253 | ||
254 | rc = LAPB_OK; | |
255 | out_put: | |
256 | lapb_put(lapb); | |
257 | out: | |
258 | return rc; | |
259 | } | |
260 | ||
261 | int lapb_connect_request(struct net_device *dev) | |
262 | { | |
263 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
264 | int rc = LAPB_BADTOKEN; | |
265 | ||
266 | if (!lapb) | |
267 | goto out; | |
268 | ||
269 | rc = LAPB_OK; | |
270 | if (lapb->state == LAPB_STATE_1) | |
271 | goto out_put; | |
272 | ||
273 | rc = LAPB_CONNECTED; | |
274 | if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4) | |
275 | goto out_put; | |
276 | ||
277 | lapb_establish_data_link(lapb); | |
278 | ||
279 | #if LAPB_DEBUG > 0 | |
280 | printk(KERN_DEBUG "lapb: (%p) S0 -> S1\n", lapb->dev); | |
281 | #endif | |
282 | lapb->state = LAPB_STATE_1; | |
283 | ||
284 | rc = LAPB_OK; | |
285 | out_put: | |
286 | lapb_put(lapb); | |
287 | out: | |
288 | return rc; | |
289 | } | |
290 | ||
291 | int lapb_disconnect_request(struct net_device *dev) | |
292 | { | |
293 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
294 | int rc = LAPB_BADTOKEN; | |
295 | ||
296 | if (!lapb) | |
297 | goto out; | |
298 | ||
299 | switch (lapb->state) { | |
300 | case LAPB_STATE_0: | |
301 | rc = LAPB_NOTCONNECTED; | |
302 | goto out_put; | |
303 | ||
304 | case LAPB_STATE_1: | |
305 | #if LAPB_DEBUG > 1 | |
306 | printk(KERN_DEBUG "lapb: (%p) S1 TX DISC(1)\n", lapb->dev); | |
307 | #endif | |
308 | #if LAPB_DEBUG > 0 | |
309 | printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", lapb->dev); | |
310 | #endif | |
311 | lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND); | |
312 | lapb->state = LAPB_STATE_0; | |
313 | lapb_start_t1timer(lapb); | |
314 | rc = LAPB_NOTCONNECTED; | |
315 | goto out_put; | |
316 | ||
317 | case LAPB_STATE_2: | |
318 | rc = LAPB_OK; | |
319 | goto out_put; | |
320 | } | |
321 | ||
322 | lapb_clear_queues(lapb); | |
323 | lapb->n2count = 0; | |
324 | lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND); | |
325 | lapb_start_t1timer(lapb); | |
326 | lapb_stop_t2timer(lapb); | |
327 | lapb->state = LAPB_STATE_2; | |
328 | ||
329 | #if LAPB_DEBUG > 1 | |
330 | printk(KERN_DEBUG "lapb: (%p) S3 DISC(1)\n", lapb->dev); | |
331 | #endif | |
332 | #if LAPB_DEBUG > 0 | |
333 | printk(KERN_DEBUG "lapb: (%p) S3 -> S2\n", lapb->dev); | |
334 | #endif | |
335 | ||
336 | rc = LAPB_OK; | |
337 | out_put: | |
338 | lapb_put(lapb); | |
339 | out: | |
340 | return rc; | |
341 | } | |
342 | ||
343 | int lapb_data_request(struct net_device *dev, struct sk_buff *skb) | |
344 | { | |
345 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
346 | int rc = LAPB_BADTOKEN; | |
347 | ||
348 | if (!lapb) | |
349 | goto out; | |
350 | ||
351 | rc = LAPB_NOTCONNECTED; | |
352 | if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4) | |
353 | goto out_put; | |
354 | ||
355 | skb_queue_tail(&lapb->write_queue, skb); | |
356 | lapb_kick(lapb); | |
357 | rc = LAPB_OK; | |
358 | out_put: | |
359 | lapb_put(lapb); | |
360 | out: | |
361 | return rc; | |
362 | } | |
363 | ||
364 | int lapb_data_received(struct net_device *dev, struct sk_buff *skb) | |
365 | { | |
366 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
367 | int rc = LAPB_BADTOKEN; | |
368 | ||
369 | if (lapb) { | |
370 | lapb_data_input(lapb, skb); | |
371 | lapb_put(lapb); | |
372 | rc = LAPB_OK; | |
373 | } | |
374 | ||
375 | return rc; | |
376 | } | |
377 | ||
378 | void lapb_connect_confirmation(struct lapb_cb *lapb, int reason) | |
379 | { | |
380 | if (lapb->callbacks.connect_confirmation) | |
381 | lapb->callbacks.connect_confirmation(lapb->dev, reason); | |
382 | } | |
383 | ||
384 | void lapb_connect_indication(struct lapb_cb *lapb, int reason) | |
385 | { | |
386 | if (lapb->callbacks.connect_indication) | |
387 | lapb->callbacks.connect_indication(lapb->dev, reason); | |
388 | } | |
389 | ||
390 | void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason) | |
391 | { | |
392 | if (lapb->callbacks.disconnect_confirmation) | |
393 | lapb->callbacks.disconnect_confirmation(lapb->dev, reason); | |
394 | } | |
395 | ||
396 | void lapb_disconnect_indication(struct lapb_cb *lapb, int reason) | |
397 | { | |
398 | if (lapb->callbacks.disconnect_indication) | |
399 | lapb->callbacks.disconnect_indication(lapb->dev, reason); | |
400 | } | |
401 | ||
402 | int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb) | |
403 | { | |
404 | if (lapb->callbacks.data_indication) | |
405 | return lapb->callbacks.data_indication(lapb->dev, skb); | |
406 | ||
407 | kfree_skb(skb); | |
408 | return NET_RX_CN_HIGH; /* For now; must be != NET_RX_DROP */ | |
409 | } | |
410 | ||
411 | int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb) | |
412 | { | |
413 | int used = 0; | |
414 | ||
415 | if (lapb->callbacks.data_transmit) { | |
416 | lapb->callbacks.data_transmit(lapb->dev, skb); | |
417 | used = 1; | |
418 | } | |
419 | ||
420 | return used; | |
421 | } | |
422 | ||
423 | EXPORT_SYMBOL(lapb_register); | |
424 | EXPORT_SYMBOL(lapb_unregister); | |
425 | EXPORT_SYMBOL(lapb_getparms); | |
426 | EXPORT_SYMBOL(lapb_setparms); | |
427 | EXPORT_SYMBOL(lapb_connect_request); | |
428 | EXPORT_SYMBOL(lapb_disconnect_request); | |
429 | EXPORT_SYMBOL(lapb_data_request); | |
430 | EXPORT_SYMBOL(lapb_data_received); | |
431 | ||
432 | static int __init lapb_init(void) | |
433 | { | |
434 | return 0; | |
435 | } | |
436 | ||
437 | static void __exit lapb_exit(void) | |
438 | { | |
439 | WARN_ON(!list_empty(&lapb_list)); | |
440 | } | |
441 | ||
442 | MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>"); | |
443 | MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol"); | |
444 | MODULE_LICENSE("GPL"); | |
445 | ||
446 | module_init(lapb_init); | |
447 | module_exit(lapb_exit); |