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 Naulor 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/errno.h> |
16 | #include <linux/types.h> |
17 | #include <linux/socket.h> |
18 | #include <linux/in.h> |
19 | #include <linux/kernel.h> |
20 | #include <linux/timer.h> |
21 | #include <linux/string.h> |
22 | #include <linux/sockios.h> |
23 | #include <linux/net.h> |
24 | #include <linux/inet.h> |
25 | #include <linux/netdevice.h> |
26 | #include <linux/skbuff.h> |
27 | #include <linux/slab.h> |
28 | #include <net/sock.h> |
29 | #include <linux/uaccess.h> |
30 | #include <linux/fcntl.h> |
31 | #include <linux/mm.h> |
32 | #include <linux/interrupt.h> |
33 | #include <net/lapb.h> |
34 | |
35 | /* |
36 | * State machine for state 0, Disconnected State. |
37 | * The handling of the timer(s) is in file lapb_timer.c. |
38 | */ |
39 | static void lapb_state0_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
40 | struct lapb_frame *frame) |
41 | { |
42 | switch (frame->type) { |
43 | case LAPB_SABM: |
44 | lapb_dbg(1, "(%p) S0 RX SABM(%d)\n" , lapb->dev, frame->pf); |
45 | if (lapb->mode & LAPB_EXTENDED) { |
46 | lapb_dbg(1, "(%p) S0 TX DM(%d)\n" , |
47 | lapb->dev, frame->pf); |
48 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
49 | LAPB_RESPONSE); |
50 | } else { |
51 | lapb_dbg(1, "(%p) S0 TX UA(%d)\n" , |
52 | lapb->dev, frame->pf); |
53 | lapb_dbg(0, "(%p) S0 -> S3\n" , lapb->dev); |
54 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
55 | LAPB_RESPONSE); |
56 | lapb_stop_t1timer(lapb); |
57 | lapb_stop_t2timer(lapb); |
58 | lapb->state = LAPB_STATE_3; |
59 | lapb->condition = 0x00; |
60 | lapb->n2count = 0; |
61 | lapb->vs = 0; |
62 | lapb->vr = 0; |
63 | lapb->va = 0; |
64 | lapb_connect_indication(lapb, LAPB_OK); |
65 | } |
66 | break; |
67 | |
68 | case LAPB_SABME: |
69 | lapb_dbg(1, "(%p) S0 RX SABME(%d)\n" , lapb->dev, frame->pf); |
70 | if (lapb->mode & LAPB_EXTENDED) { |
71 | lapb_dbg(1, "(%p) S0 TX UA(%d)\n" , |
72 | lapb->dev, frame->pf); |
73 | lapb_dbg(0, "(%p) S0 -> S3\n" , lapb->dev); |
74 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
75 | LAPB_RESPONSE); |
76 | lapb_stop_t1timer(lapb); |
77 | lapb_stop_t2timer(lapb); |
78 | lapb->state = LAPB_STATE_3; |
79 | lapb->condition = 0x00; |
80 | lapb->n2count = 0; |
81 | lapb->vs = 0; |
82 | lapb->vr = 0; |
83 | lapb->va = 0; |
84 | lapb_connect_indication(lapb, LAPB_OK); |
85 | } else { |
86 | lapb_dbg(1, "(%p) S0 TX DM(%d)\n" , |
87 | lapb->dev, frame->pf); |
88 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
89 | LAPB_RESPONSE); |
90 | } |
91 | break; |
92 | |
93 | case LAPB_DISC: |
94 | lapb_dbg(1, "(%p) S0 RX DISC(%d)\n" , lapb->dev, frame->pf); |
95 | lapb_dbg(1, "(%p) S0 TX UA(%d)\n" , lapb->dev, frame->pf); |
96 | lapb_send_control(lapb, LAPB_UA, frame->pf, LAPB_RESPONSE); |
97 | break; |
98 | |
99 | default: |
100 | break; |
101 | } |
102 | |
103 | kfree_skb(skb); |
104 | } |
105 | |
106 | /* |
107 | * State machine for state 1, Awaiting Connection State. |
108 | * The handling of the timer(s) is in file lapb_timer.c. |
109 | */ |
110 | static void lapb_state1_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
111 | struct lapb_frame *frame) |
112 | { |
113 | switch (frame->type) { |
114 | case LAPB_SABM: |
115 | lapb_dbg(1, "(%p) S1 RX SABM(%d)\n" , lapb->dev, frame->pf); |
116 | if (lapb->mode & LAPB_EXTENDED) { |
117 | lapb_dbg(1, "(%p) S1 TX DM(%d)\n" , |
118 | lapb->dev, frame->pf); |
119 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
120 | LAPB_RESPONSE); |
121 | } else { |
122 | lapb_dbg(1, "(%p) S1 TX UA(%d)\n" , |
123 | lapb->dev, frame->pf); |
124 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
125 | LAPB_RESPONSE); |
126 | } |
127 | break; |
128 | |
129 | case LAPB_SABME: |
130 | lapb_dbg(1, "(%p) S1 RX SABME(%d)\n" , lapb->dev, frame->pf); |
131 | if (lapb->mode & LAPB_EXTENDED) { |
132 | lapb_dbg(1, "(%p) S1 TX UA(%d)\n" , |
133 | lapb->dev, frame->pf); |
134 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
135 | LAPB_RESPONSE); |
136 | } else { |
137 | lapb_dbg(1, "(%p) S1 TX DM(%d)\n" , |
138 | lapb->dev, frame->pf); |
139 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
140 | LAPB_RESPONSE); |
141 | } |
142 | break; |
143 | |
144 | case LAPB_DISC: |
145 | lapb_dbg(1, "(%p) S1 RX DISC(%d)\n" , lapb->dev, frame->pf); |
146 | lapb_dbg(1, "(%p) S1 TX DM(%d)\n" , lapb->dev, frame->pf); |
147 | lapb_send_control(lapb, LAPB_DM, frame->pf, LAPB_RESPONSE); |
148 | break; |
149 | |
150 | case LAPB_UA: |
151 | lapb_dbg(1, "(%p) S1 RX UA(%d)\n" , lapb->dev, frame->pf); |
152 | if (frame->pf) { |
153 | lapb_dbg(0, "(%p) S1 -> S3\n" , lapb->dev); |
154 | lapb_stop_t1timer(lapb); |
155 | lapb_stop_t2timer(lapb); |
156 | lapb->state = LAPB_STATE_3; |
157 | lapb->condition = 0x00; |
158 | lapb->n2count = 0; |
159 | lapb->vs = 0; |
160 | lapb->vr = 0; |
161 | lapb->va = 0; |
162 | lapb_connect_confirmation(lapb, LAPB_OK); |
163 | } |
164 | break; |
165 | |
166 | case LAPB_DM: |
167 | lapb_dbg(1, "(%p) S1 RX DM(%d)\n" , lapb->dev, frame->pf); |
168 | if (frame->pf) { |
169 | lapb_dbg(0, "(%p) S1 -> S0\n" , lapb->dev); |
170 | lapb_clear_queues(lapb); |
171 | lapb->state = LAPB_STATE_0; |
172 | lapb_start_t1timer(lapb); |
173 | lapb_stop_t2timer(lapb); |
174 | lapb_disconnect_indication(lapb, LAPB_REFUSED); |
175 | } |
176 | break; |
177 | } |
178 | |
179 | kfree_skb(skb); |
180 | } |
181 | |
182 | /* |
183 | * State machine for state 2, Awaiting Release State. |
184 | * The handling of the timer(s) is in file lapb_timer.c |
185 | */ |
186 | static void lapb_state2_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
187 | struct lapb_frame *frame) |
188 | { |
189 | switch (frame->type) { |
190 | case LAPB_SABM: |
191 | case LAPB_SABME: |
192 | lapb_dbg(1, "(%p) S2 RX {SABM,SABME}(%d)\n" , |
193 | lapb->dev, frame->pf); |
194 | lapb_dbg(1, "(%p) S2 TX DM(%d)\n" , lapb->dev, frame->pf); |
195 | lapb_send_control(lapb, LAPB_DM, frame->pf, LAPB_RESPONSE); |
196 | break; |
197 | |
198 | case LAPB_DISC: |
199 | lapb_dbg(1, "(%p) S2 RX DISC(%d)\n" , lapb->dev, frame->pf); |
200 | lapb_dbg(1, "(%p) S2 TX UA(%d)\n" , lapb->dev, frame->pf); |
201 | lapb_send_control(lapb, LAPB_UA, frame->pf, LAPB_RESPONSE); |
202 | break; |
203 | |
204 | case LAPB_UA: |
205 | lapb_dbg(1, "(%p) S2 RX UA(%d)\n" , lapb->dev, frame->pf); |
206 | if (frame->pf) { |
207 | lapb_dbg(0, "(%p) S2 -> S0\n" , lapb->dev); |
208 | lapb->state = LAPB_STATE_0; |
209 | lapb_start_t1timer(lapb); |
210 | lapb_stop_t2timer(lapb); |
211 | lapb_disconnect_confirmation(lapb, LAPB_OK); |
212 | } |
213 | break; |
214 | |
215 | case LAPB_DM: |
216 | lapb_dbg(1, "(%p) S2 RX DM(%d)\n" , lapb->dev, frame->pf); |
217 | if (frame->pf) { |
218 | lapb_dbg(0, "(%p) S2 -> S0\n" , lapb->dev); |
219 | lapb->state = LAPB_STATE_0; |
220 | lapb_start_t1timer(lapb); |
221 | lapb_stop_t2timer(lapb); |
222 | lapb_disconnect_confirmation(lapb, LAPB_NOTCONNECTED); |
223 | } |
224 | break; |
225 | |
226 | case LAPB_I: |
227 | case LAPB_REJ: |
228 | case LAPB_RNR: |
229 | case LAPB_RR: |
230 | lapb_dbg(1, "(%p) S2 RX {I,REJ,RNR,RR}(%d)\n" , |
231 | lapb->dev, frame->pf); |
232 | lapb_dbg(1, "(%p) S2 RX DM(%d)\n" , lapb->dev, frame->pf); |
233 | if (frame->pf) |
234 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
235 | LAPB_RESPONSE); |
236 | break; |
237 | } |
238 | |
239 | kfree_skb(skb); |
240 | } |
241 | |
242 | /* |
243 | * State machine for state 3, Connected State. |
244 | * The handling of the timer(s) is in file lapb_timer.c |
245 | */ |
246 | static void lapb_state3_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
247 | struct lapb_frame *frame) |
248 | { |
249 | int queued = 0; |
250 | int modulus = (lapb->mode & LAPB_EXTENDED) ? LAPB_EMODULUS : |
251 | LAPB_SMODULUS; |
252 | |
253 | switch (frame->type) { |
254 | case LAPB_SABM: |
255 | lapb_dbg(1, "(%p) S3 RX SABM(%d)\n" , lapb->dev, frame->pf); |
256 | if (lapb->mode & LAPB_EXTENDED) { |
257 | lapb_dbg(1, "(%p) S3 TX DM(%d)\n" , |
258 | lapb->dev, frame->pf); |
259 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
260 | LAPB_RESPONSE); |
261 | } else { |
262 | lapb_dbg(1, "(%p) S3 TX UA(%d)\n" , |
263 | lapb->dev, frame->pf); |
264 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
265 | LAPB_RESPONSE); |
266 | lapb_stop_t1timer(lapb); |
267 | lapb_stop_t2timer(lapb); |
268 | lapb->condition = 0x00; |
269 | lapb->n2count = 0; |
270 | lapb->vs = 0; |
271 | lapb->vr = 0; |
272 | lapb->va = 0; |
273 | lapb_requeue_frames(lapb); |
274 | } |
275 | break; |
276 | |
277 | case LAPB_SABME: |
278 | lapb_dbg(1, "(%p) S3 RX SABME(%d)\n" , lapb->dev, frame->pf); |
279 | if (lapb->mode & LAPB_EXTENDED) { |
280 | lapb_dbg(1, "(%p) S3 TX UA(%d)\n" , |
281 | lapb->dev, frame->pf); |
282 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
283 | LAPB_RESPONSE); |
284 | lapb_stop_t1timer(lapb); |
285 | lapb_stop_t2timer(lapb); |
286 | lapb->condition = 0x00; |
287 | lapb->n2count = 0; |
288 | lapb->vs = 0; |
289 | lapb->vr = 0; |
290 | lapb->va = 0; |
291 | lapb_requeue_frames(lapb); |
292 | } else { |
293 | lapb_dbg(1, "(%p) S3 TX DM(%d)\n" , |
294 | lapb->dev, frame->pf); |
295 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
296 | LAPB_RESPONSE); |
297 | } |
298 | break; |
299 | |
300 | case LAPB_DISC: |
301 | lapb_dbg(1, "(%p) S3 RX DISC(%d)\n" , lapb->dev, frame->pf); |
302 | lapb_dbg(0, "(%p) S3 -> S0\n" , lapb->dev); |
303 | lapb_clear_queues(lapb); |
304 | lapb_send_control(lapb, LAPB_UA, frame->pf, LAPB_RESPONSE); |
305 | lapb_start_t1timer(lapb); |
306 | lapb_stop_t2timer(lapb); |
307 | lapb->state = LAPB_STATE_0; |
308 | lapb_disconnect_indication(lapb, LAPB_OK); |
309 | break; |
310 | |
311 | case LAPB_DM: |
312 | lapb_dbg(1, "(%p) S3 RX DM(%d)\n" , lapb->dev, frame->pf); |
313 | lapb_dbg(0, "(%p) S3 -> S0\n" , lapb->dev); |
314 | lapb_clear_queues(lapb); |
315 | lapb->state = LAPB_STATE_0; |
316 | lapb_start_t1timer(lapb); |
317 | lapb_stop_t2timer(lapb); |
318 | lapb_disconnect_indication(lapb, LAPB_NOTCONNECTED); |
319 | break; |
320 | |
321 | case LAPB_RNR: |
322 | lapb_dbg(1, "(%p) S3 RX RNR(%d) R%d\n" , |
323 | lapb->dev, frame->pf, frame->nr); |
324 | lapb->condition |= LAPB_PEER_RX_BUSY_CONDITION; |
325 | lapb_check_need_response(lapb, frame->cr, frame->pf); |
326 | if (lapb_validate_nr(lapb, frame->nr)) { |
327 | lapb_check_iframes_acked(lapb, frame->nr); |
328 | } else { |
329 | lapb->frmr_data = *frame; |
330 | lapb->frmr_type = LAPB_FRMR_Z; |
331 | lapb_transmit_frmr(lapb); |
332 | lapb_dbg(0, "(%p) S3 -> S4\n" , lapb->dev); |
333 | lapb_start_t1timer(lapb); |
334 | lapb_stop_t2timer(lapb); |
335 | lapb->state = LAPB_STATE_4; |
336 | lapb->n2count = 0; |
337 | } |
338 | break; |
339 | |
340 | case LAPB_RR: |
341 | lapb_dbg(1, "(%p) S3 RX RR(%d) R%d\n" , |
342 | lapb->dev, frame->pf, frame->nr); |
343 | lapb->condition &= ~LAPB_PEER_RX_BUSY_CONDITION; |
344 | lapb_check_need_response(lapb, frame->cr, frame->pf); |
345 | if (lapb_validate_nr(lapb, frame->nr)) { |
346 | lapb_check_iframes_acked(lapb, frame->nr); |
347 | } else { |
348 | lapb->frmr_data = *frame; |
349 | lapb->frmr_type = LAPB_FRMR_Z; |
350 | lapb_transmit_frmr(lapb); |
351 | lapb_dbg(0, "(%p) S3 -> S4\n" , lapb->dev); |
352 | lapb_start_t1timer(lapb); |
353 | lapb_stop_t2timer(lapb); |
354 | lapb->state = LAPB_STATE_4; |
355 | lapb->n2count = 0; |
356 | } |
357 | break; |
358 | |
359 | case LAPB_REJ: |
360 | lapb_dbg(1, "(%p) S3 RX REJ(%d) R%d\n" , |
361 | lapb->dev, frame->pf, frame->nr); |
362 | lapb->condition &= ~LAPB_PEER_RX_BUSY_CONDITION; |
363 | lapb_check_need_response(lapb, frame->cr, frame->pf); |
364 | if (lapb_validate_nr(lapb, frame->nr)) { |
365 | lapb_frames_acked(lapb, frame->nr); |
366 | lapb_stop_t1timer(lapb); |
367 | lapb->n2count = 0; |
368 | lapb_requeue_frames(lapb); |
369 | } else { |
370 | lapb->frmr_data = *frame; |
371 | lapb->frmr_type = LAPB_FRMR_Z; |
372 | lapb_transmit_frmr(lapb); |
373 | lapb_dbg(0, "(%p) S3 -> S4\n" , lapb->dev); |
374 | lapb_start_t1timer(lapb); |
375 | lapb_stop_t2timer(lapb); |
376 | lapb->state = LAPB_STATE_4; |
377 | lapb->n2count = 0; |
378 | } |
379 | break; |
380 | |
381 | case LAPB_I: |
382 | lapb_dbg(1, "(%p) S3 RX I(%d) S%d R%d\n" , |
383 | lapb->dev, frame->pf, frame->ns, frame->nr); |
384 | if (!lapb_validate_nr(lapb, frame->nr)) { |
385 | lapb->frmr_data = *frame; |
386 | lapb->frmr_type = LAPB_FRMR_Z; |
387 | lapb_transmit_frmr(lapb); |
388 | lapb_dbg(0, "(%p) S3 -> S4\n" , lapb->dev); |
389 | lapb_start_t1timer(lapb); |
390 | lapb_stop_t2timer(lapb); |
391 | lapb->state = LAPB_STATE_4; |
392 | lapb->n2count = 0; |
393 | break; |
394 | } |
395 | if (lapb->condition & LAPB_PEER_RX_BUSY_CONDITION) |
396 | lapb_frames_acked(lapb, frame->nr); |
397 | else |
398 | lapb_check_iframes_acked(lapb, frame->nr); |
399 | |
400 | if (frame->ns == lapb->vr) { |
401 | int cn; |
402 | cn = lapb_data_indication(lapb, skb); |
403 | queued = 1; |
404 | /* |
405 | * If upper layer has dropped the frame, we |
406 | * basically ignore any further protocol |
407 | * processing. This will cause the peer |
408 | * to re-transmit the frame later like |
409 | * a frame lost on the wire. |
410 | */ |
411 | if (cn == NET_RX_DROP) { |
412 | pr_debug("rx congestion\n" ); |
413 | break; |
414 | } |
415 | lapb->vr = (lapb->vr + 1) % modulus; |
416 | lapb->condition &= ~LAPB_REJECT_CONDITION; |
417 | if (frame->pf) |
418 | lapb_enquiry_response(lapb); |
419 | else { |
420 | if (!(lapb->condition & |
421 | LAPB_ACK_PENDING_CONDITION)) { |
422 | lapb->condition |= LAPB_ACK_PENDING_CONDITION; |
423 | lapb_start_t2timer(lapb); |
424 | } |
425 | } |
426 | } else { |
427 | if (lapb->condition & LAPB_REJECT_CONDITION) { |
428 | if (frame->pf) |
429 | lapb_enquiry_response(lapb); |
430 | } else { |
431 | lapb_dbg(1, "(%p) S3 TX REJ(%d) R%d\n" , |
432 | lapb->dev, frame->pf, lapb->vr); |
433 | lapb->condition |= LAPB_REJECT_CONDITION; |
434 | lapb_send_control(lapb, LAPB_REJ, frame->pf, |
435 | LAPB_RESPONSE); |
436 | lapb->condition &= ~LAPB_ACK_PENDING_CONDITION; |
437 | } |
438 | } |
439 | break; |
440 | |
441 | case LAPB_FRMR: |
442 | lapb_dbg(1, "(%p) S3 RX FRMR(%d) %5ph\n" , |
443 | lapb->dev, frame->pf, |
444 | skb->data); |
445 | lapb_establish_data_link(lapb); |
446 | lapb_dbg(0, "(%p) S3 -> S1\n" , lapb->dev); |
447 | lapb_requeue_frames(lapb); |
448 | lapb->state = LAPB_STATE_1; |
449 | break; |
450 | |
451 | case LAPB_ILLEGAL: |
452 | lapb_dbg(1, "(%p) S3 RX ILLEGAL(%d)\n" , lapb->dev, frame->pf); |
453 | lapb->frmr_data = *frame; |
454 | lapb->frmr_type = LAPB_FRMR_W; |
455 | lapb_transmit_frmr(lapb); |
456 | lapb_dbg(0, "(%p) S3 -> S4\n" , lapb->dev); |
457 | lapb_start_t1timer(lapb); |
458 | lapb_stop_t2timer(lapb); |
459 | lapb->state = LAPB_STATE_4; |
460 | lapb->n2count = 0; |
461 | break; |
462 | } |
463 | |
464 | if (!queued) |
465 | kfree_skb(skb); |
466 | } |
467 | |
468 | /* |
469 | * State machine for state 4, Frame Reject State. |
470 | * The handling of the timer(s) is in file lapb_timer.c. |
471 | */ |
472 | static void lapb_state4_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
473 | struct lapb_frame *frame) |
474 | { |
475 | switch (frame->type) { |
476 | case LAPB_SABM: |
477 | lapb_dbg(1, "(%p) S4 RX SABM(%d)\n" , lapb->dev, frame->pf); |
478 | if (lapb->mode & LAPB_EXTENDED) { |
479 | lapb_dbg(1, "(%p) S4 TX DM(%d)\n" , |
480 | lapb->dev, frame->pf); |
481 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
482 | LAPB_RESPONSE); |
483 | } else { |
484 | lapb_dbg(1, "(%p) S4 TX UA(%d)\n" , |
485 | lapb->dev, frame->pf); |
486 | lapb_dbg(0, "(%p) S4 -> S3\n" , lapb->dev); |
487 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
488 | LAPB_RESPONSE); |
489 | lapb_stop_t1timer(lapb); |
490 | lapb_stop_t2timer(lapb); |
491 | lapb->state = LAPB_STATE_3; |
492 | lapb->condition = 0x00; |
493 | lapb->n2count = 0; |
494 | lapb->vs = 0; |
495 | lapb->vr = 0; |
496 | lapb->va = 0; |
497 | lapb_connect_indication(lapb, LAPB_OK); |
498 | } |
499 | break; |
500 | |
501 | case LAPB_SABME: |
502 | lapb_dbg(1, "(%p) S4 RX SABME(%d)\n" , lapb->dev, frame->pf); |
503 | if (lapb->mode & LAPB_EXTENDED) { |
504 | lapb_dbg(1, "(%p) S4 TX UA(%d)\n" , |
505 | lapb->dev, frame->pf); |
506 | lapb_dbg(0, "(%p) S4 -> S3\n" , lapb->dev); |
507 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
508 | LAPB_RESPONSE); |
509 | lapb_stop_t1timer(lapb); |
510 | lapb_stop_t2timer(lapb); |
511 | lapb->state = LAPB_STATE_3; |
512 | lapb->condition = 0x00; |
513 | lapb->n2count = 0; |
514 | lapb->vs = 0; |
515 | lapb->vr = 0; |
516 | lapb->va = 0; |
517 | lapb_connect_indication(lapb, LAPB_OK); |
518 | } else { |
519 | lapb_dbg(1, "(%p) S4 TX DM(%d)\n" , |
520 | lapb->dev, frame->pf); |
521 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
522 | LAPB_RESPONSE); |
523 | } |
524 | break; |
525 | } |
526 | |
527 | kfree_skb(skb); |
528 | } |
529 | |
530 | /* |
531 | * Process an incoming LAPB frame |
532 | */ |
533 | void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *skb) |
534 | { |
535 | struct lapb_frame frame; |
536 | |
537 | if (lapb_decode(lapb, skb, &frame) < 0) { |
538 | kfree_skb(skb); |
539 | return; |
540 | } |
541 | |
542 | switch (lapb->state) { |
543 | case LAPB_STATE_0: |
544 | lapb_state0_machine(lapb, skb, frame: &frame); break; |
545 | case LAPB_STATE_1: |
546 | lapb_state1_machine(lapb, skb, frame: &frame); break; |
547 | case LAPB_STATE_2: |
548 | lapb_state2_machine(lapb, skb, frame: &frame); break; |
549 | case LAPB_STATE_3: |
550 | lapb_state3_machine(lapb, skb, frame: &frame); break; |
551 | case LAPB_STATE_4: |
552 | lapb_state4_machine(lapb, skb, frame: &frame); break; |
553 | } |
554 | |
555 | lapb_kick(lapb); |
556 | } |
557 | |