Commit | Line | Data |
---|---|---|
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 | { | |
118 | struct lapb_cb *lapb = kmalloc(sizeof(*lapb), GFP_ATOMIC); | |
119 | ||
120 | ||
121 | if (!lapb) | |
122 | goto out; | |
123 | ||
124 | memset(lapb, 0x00, sizeof(*lapb)); | |
125 | ||
126 | skb_queue_head_init(&lapb->write_queue); | |
127 | skb_queue_head_init(&lapb->ack_queue); | |
128 | ||
129 | init_timer(&lapb->t1timer); | |
130 | init_timer(&lapb->t2timer); | |
131 | ||
132 | lapb->t1 = LAPB_DEFAULT_T1; | |
133 | lapb->t2 = LAPB_DEFAULT_T2; | |
134 | lapb->n2 = LAPB_DEFAULT_N2; | |
135 | lapb->mode = LAPB_DEFAULT_MODE; | |
136 | lapb->window = LAPB_DEFAULT_WINDOW; | |
137 | lapb->state = LAPB_STATE_0; | |
138 | atomic_set(&lapb->refcnt, 1); | |
139 | out: | |
140 | return lapb; | |
141 | } | |
142 | ||
143 | int lapb_register(struct net_device *dev, struct lapb_register_struct *callbacks) | |
144 | { | |
145 | struct lapb_cb *lapb; | |
146 | int rc = LAPB_BADTOKEN; | |
147 | ||
148 | write_lock_bh(&lapb_list_lock); | |
149 | ||
150 | lapb = __lapb_devtostruct(dev); | |
151 | if (lapb) { | |
152 | lapb_put(lapb); | |
153 | goto out; | |
154 | } | |
155 | ||
156 | lapb = lapb_create_cb(); | |
157 | rc = LAPB_NOMEM; | |
158 | if (!lapb) | |
159 | goto out; | |
160 | ||
161 | lapb->dev = dev; | |
162 | lapb->callbacks = *callbacks; | |
163 | ||
164 | __lapb_insert_cb(lapb); | |
165 | ||
166 | lapb_start_t1timer(lapb); | |
167 | ||
168 | rc = LAPB_OK; | |
169 | out: | |
170 | write_unlock_bh(&lapb_list_lock); | |
171 | return rc; | |
172 | } | |
173 | ||
174 | int lapb_unregister(struct net_device *dev) | |
175 | { | |
176 | struct lapb_cb *lapb; | |
177 | int rc = LAPB_BADTOKEN; | |
178 | ||
179 | write_lock_bh(&lapb_list_lock); | |
180 | lapb = __lapb_devtostruct(dev); | |
181 | if (!lapb) | |
182 | goto out; | |
183 | ||
184 | lapb_stop_t1timer(lapb); | |
185 | lapb_stop_t2timer(lapb); | |
186 | ||
187 | lapb_clear_queues(lapb); | |
188 | ||
189 | __lapb_remove_cb(lapb); | |
190 | ||
191 | lapb_put(lapb); | |
192 | rc = LAPB_OK; | |
193 | out: | |
194 | write_unlock_bh(&lapb_list_lock); | |
195 | return rc; | |
196 | } | |
197 | ||
198 | int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms) | |
199 | { | |
200 | int rc = LAPB_BADTOKEN; | |
201 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
202 | ||
203 | if (!lapb) | |
204 | goto out; | |
205 | ||
206 | parms->t1 = lapb->t1 / HZ; | |
207 | parms->t2 = lapb->t2 / HZ; | |
208 | parms->n2 = lapb->n2; | |
209 | parms->n2count = lapb->n2count; | |
210 | parms->state = lapb->state; | |
211 | parms->window = lapb->window; | |
212 | parms->mode = lapb->mode; | |
213 | ||
214 | if (!timer_pending(&lapb->t1timer)) | |
215 | parms->t1timer = 0; | |
216 | else | |
217 | parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ; | |
218 | ||
219 | if (!timer_pending(&lapb->t2timer)) | |
220 | parms->t2timer = 0; | |
221 | else | |
222 | parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ; | |
223 | ||
224 | lapb_put(lapb); | |
225 | rc = LAPB_OK; | |
226 | out: | |
227 | return rc; | |
228 | } | |
229 | ||
230 | int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms) | |
231 | { | |
232 | int rc = LAPB_BADTOKEN; | |
233 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
234 | ||
235 | if (!lapb) | |
236 | goto out; | |
237 | ||
238 | rc = LAPB_INVALUE; | |
239 | if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1) | |
240 | goto out_put; | |
241 | ||
242 | if (lapb->state == LAPB_STATE_0) { | |
243 | if (((parms->mode & LAPB_EXTENDED) && | |
244 | (parms->window < 1 || parms->window > 127)) || | |
245 | (parms->window < 1 || parms->window > 7)) | |
246 | goto out_put; | |
247 | ||
248 | lapb->mode = parms->mode; | |
249 | lapb->window = parms->window; | |
250 | } | |
251 | ||
252 | lapb->t1 = parms->t1 * HZ; | |
253 | lapb->t2 = parms->t2 * HZ; | |
254 | lapb->n2 = parms->n2; | |
255 | ||
256 | rc = LAPB_OK; | |
257 | out_put: | |
258 | lapb_put(lapb); | |
259 | out: | |
260 | return rc; | |
261 | } | |
262 | ||
263 | int lapb_connect_request(struct net_device *dev) | |
264 | { | |
265 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
266 | int rc = LAPB_BADTOKEN; | |
267 | ||
268 | if (!lapb) | |
269 | goto out; | |
270 | ||
271 | rc = LAPB_OK; | |
272 | if (lapb->state == LAPB_STATE_1) | |
273 | goto out_put; | |
274 | ||
275 | rc = LAPB_CONNECTED; | |
276 | if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4) | |
277 | goto out_put; | |
278 | ||
279 | lapb_establish_data_link(lapb); | |
280 | ||
281 | #if LAPB_DEBUG > 0 | |
282 | printk(KERN_DEBUG "lapb: (%p) S0 -> S1\n", lapb->dev); | |
283 | #endif | |
284 | lapb->state = LAPB_STATE_1; | |
285 | ||
286 | rc = LAPB_OK; | |
287 | out_put: | |
288 | lapb_put(lapb); | |
289 | out: | |
290 | return rc; | |
291 | } | |
292 | ||
293 | int lapb_disconnect_request(struct net_device *dev) | |
294 | { | |
295 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
296 | int rc = LAPB_BADTOKEN; | |
297 | ||
298 | if (!lapb) | |
299 | goto out; | |
300 | ||
301 | switch (lapb->state) { | |
302 | case LAPB_STATE_0: | |
303 | rc = LAPB_NOTCONNECTED; | |
304 | goto out_put; | |
305 | ||
306 | case LAPB_STATE_1: | |
307 | #if LAPB_DEBUG > 1 | |
308 | printk(KERN_DEBUG "lapb: (%p) S1 TX DISC(1)\n", lapb->dev); | |
309 | #endif | |
310 | #if LAPB_DEBUG > 0 | |
311 | printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", lapb->dev); | |
312 | #endif | |
313 | lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND); | |
314 | lapb->state = LAPB_STATE_0; | |
315 | lapb_start_t1timer(lapb); | |
316 | rc = LAPB_NOTCONNECTED; | |
317 | goto out_put; | |
318 | ||
319 | case LAPB_STATE_2: | |
320 | rc = LAPB_OK; | |
321 | goto out_put; | |
322 | } | |
323 | ||
324 | lapb_clear_queues(lapb); | |
325 | lapb->n2count = 0; | |
326 | lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND); | |
327 | lapb_start_t1timer(lapb); | |
328 | lapb_stop_t2timer(lapb); | |
329 | lapb->state = LAPB_STATE_2; | |
330 | ||
331 | #if LAPB_DEBUG > 1 | |
332 | printk(KERN_DEBUG "lapb: (%p) S3 DISC(1)\n", lapb->dev); | |
333 | #endif | |
334 | #if LAPB_DEBUG > 0 | |
335 | printk(KERN_DEBUG "lapb: (%p) S3 -> S2\n", lapb->dev); | |
336 | #endif | |
337 | ||
338 | rc = LAPB_OK; | |
339 | out_put: | |
340 | lapb_put(lapb); | |
341 | out: | |
342 | return rc; | |
343 | } | |
344 | ||
345 | int lapb_data_request(struct net_device *dev, struct sk_buff *skb) | |
346 | { | |
347 | struct lapb_cb *lapb = lapb_devtostruct(dev); | |
348 | int rc = LAPB_BADTOKEN; | |
349 | ||
350 | if (!lapb) | |
351 | goto out; | |
352 | ||
353 | rc = LAPB_NOTCONNECTED; | |
354 | if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4) | |
355 | goto out_put; | |
356 | ||
357 | skb_queue_tail(&lapb->write_queue, skb); | |
358 | lapb_kick(lapb); | |
359 | rc = LAPB_OK; | |
360 | out_put: | |
361 | lapb_put(lapb); | |
362 | out: | |
363 | return rc; | |
364 | } | |
365 | ||
366 | int 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 | } | |
379 | ||
380 | void lapb_connect_confirmation(struct lapb_cb *lapb, int reason) | |
381 | { | |
382 | if (lapb->callbacks.connect_confirmation) | |
383 | lapb->callbacks.connect_confirmation(lapb->dev, reason); | |
384 | } | |
385 | ||
386 | void lapb_connect_indication(struct lapb_cb *lapb, int reason) | |
387 | { | |
388 | if (lapb->callbacks.connect_indication) | |
389 | lapb->callbacks.connect_indication(lapb->dev, reason); | |
390 | } | |
391 | ||
392 | void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason) | |
393 | { | |
394 | if (lapb->callbacks.disconnect_confirmation) | |
395 | lapb->callbacks.disconnect_confirmation(lapb->dev, reason); | |
396 | } | |
397 | ||
398 | void lapb_disconnect_indication(struct lapb_cb *lapb, int reason) | |
399 | { | |
400 | if (lapb->callbacks.disconnect_indication) | |
401 | lapb->callbacks.disconnect_indication(lapb->dev, reason); | |
402 | } | |
403 | ||
404 | int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb) | |
405 | { | |
406 | if (lapb->callbacks.data_indication) | |
407 | return lapb->callbacks.data_indication(lapb->dev, skb); | |
408 | ||
409 | kfree_skb(skb); | |
410 | return NET_RX_CN_HIGH; /* For now; must be != NET_RX_DROP */ | |
411 | } | |
412 | ||
413 | int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb) | |
414 | { | |
415 | int used = 0; | |
416 | ||
417 | if (lapb->callbacks.data_transmit) { | |
418 | lapb->callbacks.data_transmit(lapb->dev, skb); | |
419 | used = 1; | |
420 | } | |
421 | ||
422 | return used; | |
423 | } | |
424 | ||
425 | EXPORT_SYMBOL(lapb_register); | |
426 | EXPORT_SYMBOL(lapb_unregister); | |
427 | EXPORT_SYMBOL(lapb_getparms); | |
428 | EXPORT_SYMBOL(lapb_setparms); | |
429 | EXPORT_SYMBOL(lapb_connect_request); | |
430 | EXPORT_SYMBOL(lapb_disconnect_request); | |
431 | EXPORT_SYMBOL(lapb_data_request); | |
432 | EXPORT_SYMBOL(lapb_data_received); | |
433 | ||
434 | static int __init lapb_init(void) | |
435 | { | |
436 | return 0; | |
437 | } | |
438 | ||
439 | static void __exit lapb_exit(void) | |
440 | { | |
441 | WARN_ON(!list_empty(&lapb_list)); | |
442 | } | |
443 | ||
444 | MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>"); | |
445 | MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol"); | |
446 | MODULE_LICENSE("GPL"); | |
447 | ||
448 | module_init(lapb_init); | |
449 | module_exit(lapb_exit); |