Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 Naulor 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/errno.h> |
| 19 | #include <linux/types.h> |
| 20 | #include <linux/socket.h> |
| 21 | #include <linux/in.h> |
| 22 | #include <linux/kernel.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <linux/timer.h> |
| 24 | #include <linux/string.h> |
| 25 | #include <linux/sockios.h> |
| 26 | #include <linux/net.h> |
| 27 | #include <linux/inet.h> |
| 28 | #include <linux/netdevice.h> |
| 29 | #include <linux/skbuff.h> |
| 30 | #include <net/sock.h> |
| 31 | #include <asm/uaccess.h> |
| 32 | #include <asm/system.h> |
| 33 | #include <linux/fcntl.h> |
| 34 | #include <linux/mm.h> |
| 35 | #include <linux/interrupt.h> |
| 36 | #include <net/lapb.h> |
| 37 | |
| 38 | /* |
| 39 | * State machine for state 0, Disconnected State. |
| 40 | * The handling of the timer(s) is in file lapb_timer.c. |
| 41 | */ |
| 42 | static void lapb_state0_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
| 43 | struct lapb_frame *frame) |
| 44 | { |
| 45 | switch (frame->type) { |
| 46 | case LAPB_SABM: |
| 47 | #if LAPB_DEBUG > 1 |
| 48 | printk(KERN_DEBUG "lapb: (%p) S0 RX SABM(%d)\n", |
| 49 | lapb->dev, frame->pf); |
| 50 | #endif |
| 51 | if (lapb->mode & LAPB_EXTENDED) { |
| 52 | #if LAPB_DEBUG > 1 |
| 53 | printk(KERN_DEBUG "lapb: (%p) S0 TX DM(%d)\n", |
| 54 | lapb->dev, frame->pf); |
| 55 | #endif |
| 56 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 57 | LAPB_RESPONSE); |
| 58 | } else { |
| 59 | #if LAPB_DEBUG > 1 |
| 60 | printk(KERN_DEBUG "lapb: (%p) S0 TX UA(%d)\n", |
| 61 | lapb->dev, frame->pf); |
| 62 | #endif |
| 63 | #if LAPB_DEBUG > 0 |
| 64 | printk(KERN_DEBUG "lapb: (%p) S0 -> S3\n", |
| 65 | lapb->dev); |
| 66 | #endif |
| 67 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 68 | LAPB_RESPONSE); |
| 69 | lapb_stop_t1timer(lapb); |
| 70 | lapb_stop_t2timer(lapb); |
| 71 | lapb->state = LAPB_STATE_3; |
| 72 | lapb->condition = 0x00; |
| 73 | lapb->n2count = 0; |
| 74 | lapb->vs = 0; |
| 75 | lapb->vr = 0; |
| 76 | lapb->va = 0; |
| 77 | lapb_connect_indication(lapb, LAPB_OK); |
| 78 | } |
| 79 | break; |
| 80 | |
| 81 | case LAPB_SABME: |
| 82 | #if LAPB_DEBUG > 1 |
| 83 | printk(KERN_DEBUG "lapb: (%p) S0 RX SABME(%d)\n", |
| 84 | lapb->dev, frame->pf); |
| 85 | #endif |
| 86 | if (lapb->mode & LAPB_EXTENDED) { |
| 87 | #if LAPB_DEBUG > 1 |
| 88 | printk(KERN_DEBUG "lapb: (%p) S0 TX UA(%d)\n", |
| 89 | lapb->dev, frame->pf); |
| 90 | #endif |
| 91 | #if LAPB_DEBUG > 0 |
| 92 | printk(KERN_DEBUG "lapb: (%p) S0 -> S3\n", |
| 93 | lapb->dev); |
| 94 | #endif |
| 95 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 96 | LAPB_RESPONSE); |
| 97 | lapb_stop_t1timer(lapb); |
| 98 | lapb_stop_t2timer(lapb); |
| 99 | lapb->state = LAPB_STATE_3; |
| 100 | lapb->condition = 0x00; |
| 101 | lapb->n2count = 0; |
| 102 | lapb->vs = 0; |
| 103 | lapb->vr = 0; |
| 104 | lapb->va = 0; |
| 105 | lapb_connect_indication(lapb, LAPB_OK); |
| 106 | } else { |
| 107 | #if LAPB_DEBUG > 1 |
| 108 | printk(KERN_DEBUG "lapb: (%p) S0 TX DM(%d)\n", |
| 109 | lapb->dev, frame->pf); |
| 110 | #endif |
| 111 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 112 | LAPB_RESPONSE); |
| 113 | } |
| 114 | break; |
| 115 | |
| 116 | case LAPB_DISC: |
| 117 | #if LAPB_DEBUG > 1 |
| 118 | printk(KERN_DEBUG "lapb: (%p) S0 RX DISC(%d)\n", |
| 119 | lapb->dev, frame->pf); |
| 120 | printk(KERN_DEBUG "lapb: (%p) S0 TX UA(%d)\n", |
| 121 | lapb->dev, frame->pf); |
| 122 | #endif |
| 123 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 124 | LAPB_RESPONSE); |
| 125 | break; |
| 126 | |
| 127 | default: |
| 128 | break; |
| 129 | } |
| 130 | |
| 131 | kfree_skb(skb); |
| 132 | } |
| 133 | |
| 134 | /* |
| 135 | * State machine for state 1, Awaiting Connection State. |
| 136 | * The handling of the timer(s) is in file lapb_timer.c. |
| 137 | */ |
| 138 | static void lapb_state1_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
| 139 | struct lapb_frame *frame) |
| 140 | { |
| 141 | switch (frame->type) { |
| 142 | case LAPB_SABM: |
| 143 | #if LAPB_DEBUG > 1 |
| 144 | printk(KERN_DEBUG "lapb: (%p) S1 RX SABM(%d)\n", |
| 145 | lapb->dev, frame->pf); |
| 146 | #endif |
| 147 | if (lapb->mode & LAPB_EXTENDED) { |
| 148 | #if LAPB_DEBUG > 1 |
| 149 | printk(KERN_DEBUG "lapb: (%p) S1 TX DM(%d)\n", |
| 150 | lapb->dev, frame->pf); |
| 151 | #endif |
| 152 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 153 | LAPB_RESPONSE); |
| 154 | } else { |
| 155 | #if LAPB_DEBUG > 1 |
| 156 | printk(KERN_DEBUG "lapb: (%p) S1 TX UA(%d)\n", |
| 157 | lapb->dev, frame->pf); |
| 158 | #endif |
| 159 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 160 | LAPB_RESPONSE); |
| 161 | } |
| 162 | break; |
| 163 | |
| 164 | case LAPB_SABME: |
| 165 | #if LAPB_DEBUG > 1 |
| 166 | printk(KERN_DEBUG "lapb: (%p) S1 RX SABME(%d)\n", |
| 167 | lapb->dev, frame->pf); |
| 168 | #endif |
| 169 | if (lapb->mode & LAPB_EXTENDED) { |
| 170 | #if LAPB_DEBUG > 1 |
| 171 | printk(KERN_DEBUG "lapb: (%p) S1 TX UA(%d)\n", |
| 172 | lapb->dev, frame->pf); |
| 173 | #endif |
| 174 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 175 | LAPB_RESPONSE); |
| 176 | } else { |
| 177 | #if LAPB_DEBUG > 1 |
| 178 | printk(KERN_DEBUG "lapb: (%p) S1 TX DM(%d)\n", |
| 179 | lapb->dev, frame->pf); |
| 180 | #endif |
| 181 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 182 | LAPB_RESPONSE); |
| 183 | } |
| 184 | break; |
| 185 | |
| 186 | case LAPB_DISC: |
| 187 | #if LAPB_DEBUG > 1 |
| 188 | printk(KERN_DEBUG "lapb: (%p) S1 RX DISC(%d)\n", |
| 189 | lapb->dev, frame->pf); |
| 190 | printk(KERN_DEBUG "lapb: (%p) S1 TX DM(%d)\n", |
| 191 | lapb->dev, frame->pf); |
| 192 | #endif |
| 193 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 194 | LAPB_RESPONSE); |
| 195 | break; |
| 196 | |
| 197 | case LAPB_UA: |
| 198 | #if LAPB_DEBUG > 1 |
| 199 | printk(KERN_DEBUG "lapb: (%p) S1 RX UA(%d)\n", |
| 200 | lapb->dev, frame->pf); |
| 201 | #endif |
| 202 | if (frame->pf) { |
| 203 | #if LAPB_DEBUG > 0 |
| 204 | printk(KERN_DEBUG "lapb: (%p) S1 -> S3\n", |
| 205 | lapb->dev); |
| 206 | #endif |
| 207 | lapb_stop_t1timer(lapb); |
| 208 | lapb_stop_t2timer(lapb); |
| 209 | lapb->state = LAPB_STATE_3; |
| 210 | lapb->condition = 0x00; |
| 211 | lapb->n2count = 0; |
| 212 | lapb->vs = 0; |
| 213 | lapb->vr = 0; |
| 214 | lapb->va = 0; |
| 215 | lapb_connect_confirmation(lapb, LAPB_OK); |
| 216 | } |
| 217 | break; |
| 218 | |
| 219 | case LAPB_DM: |
| 220 | #if LAPB_DEBUG > 1 |
| 221 | printk(KERN_DEBUG "lapb: (%p) S1 RX DM(%d)\n", |
| 222 | lapb->dev, frame->pf); |
| 223 | #endif |
| 224 | if (frame->pf) { |
| 225 | #if LAPB_DEBUG > 0 |
| 226 | printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", |
| 227 | lapb->dev); |
| 228 | #endif |
| 229 | lapb_clear_queues(lapb); |
| 230 | lapb->state = LAPB_STATE_0; |
| 231 | lapb_start_t1timer(lapb); |
| 232 | lapb_stop_t2timer(lapb); |
| 233 | lapb_disconnect_indication(lapb, LAPB_REFUSED); |
| 234 | } |
| 235 | break; |
| 236 | } |
| 237 | |
| 238 | kfree_skb(skb); |
| 239 | } |
| 240 | |
| 241 | /* |
| 242 | * State machine for state 2, Awaiting Release State. |
| 243 | * The handling of the timer(s) is in file lapb_timer.c |
| 244 | */ |
| 245 | static void lapb_state2_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
| 246 | struct lapb_frame *frame) |
| 247 | { |
| 248 | switch (frame->type) { |
| 249 | case LAPB_SABM: |
| 250 | case LAPB_SABME: |
| 251 | #if LAPB_DEBUG > 1 |
| 252 | printk(KERN_DEBUG "lapb: (%p) S2 RX {SABM,SABME}(%d)\n", |
| 253 | lapb->dev, frame->pf); |
| 254 | printk(KERN_DEBUG "lapb: (%p) S2 TX DM(%d)\n", |
| 255 | lapb->dev, frame->pf); |
| 256 | #endif |
| 257 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 258 | LAPB_RESPONSE); |
| 259 | break; |
| 260 | |
| 261 | case LAPB_DISC: |
| 262 | #if LAPB_DEBUG > 1 |
| 263 | printk(KERN_DEBUG "lapb: (%p) S2 RX DISC(%d)\n", |
| 264 | lapb->dev, frame->pf); |
| 265 | printk(KERN_DEBUG "lapb: (%p) S2 TX UA(%d)\n", |
| 266 | lapb->dev, frame->pf); |
| 267 | #endif |
| 268 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 269 | LAPB_RESPONSE); |
| 270 | break; |
| 271 | |
| 272 | case LAPB_UA: |
| 273 | #if LAPB_DEBUG > 1 |
| 274 | printk(KERN_DEBUG "lapb: (%p) S2 RX UA(%d)\n", |
| 275 | lapb->dev, frame->pf); |
| 276 | #endif |
| 277 | if (frame->pf) { |
| 278 | #if LAPB_DEBUG > 0 |
| 279 | printk(KERN_DEBUG "lapb: (%p) S2 -> S0\n", |
| 280 | lapb->dev); |
| 281 | #endif |
| 282 | lapb->state = LAPB_STATE_0; |
| 283 | lapb_start_t1timer(lapb); |
| 284 | lapb_stop_t2timer(lapb); |
| 285 | lapb_disconnect_confirmation(lapb, LAPB_OK); |
| 286 | } |
| 287 | break; |
| 288 | |
| 289 | case LAPB_DM: |
| 290 | #if LAPB_DEBUG > 1 |
| 291 | printk(KERN_DEBUG "lapb: (%p) S2 RX DM(%d)\n", |
| 292 | lapb->dev, frame->pf); |
| 293 | #endif |
| 294 | if (frame->pf) { |
| 295 | #if LAPB_DEBUG > 0 |
| 296 | printk(KERN_DEBUG "lapb: (%p) S2 -> S0\n", |
| 297 | lapb->dev); |
| 298 | #endif |
| 299 | lapb->state = LAPB_STATE_0; |
| 300 | lapb_start_t1timer(lapb); |
| 301 | lapb_stop_t2timer(lapb); |
| 302 | lapb_disconnect_confirmation(lapb, |
| 303 | LAPB_NOTCONNECTED); |
| 304 | } |
| 305 | break; |
| 306 | |
| 307 | case LAPB_I: |
| 308 | case LAPB_REJ: |
| 309 | case LAPB_RNR: |
| 310 | case LAPB_RR: |
| 311 | #if LAPB_DEBUG > 1 |
| 312 | printk(KERN_DEBUG "lapb: (%p) S2 RX {I,REJ,RNR,RR}" |
| 313 | "(%d)\n", lapb->dev, frame->pf); |
| 314 | printk(KERN_DEBUG "lapb: (%p) S2 RX DM(%d)\n", |
| 315 | lapb->dev, frame->pf); |
| 316 | #endif |
| 317 | if (frame->pf) |
| 318 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 319 | LAPB_RESPONSE); |
| 320 | break; |
| 321 | } |
| 322 | |
| 323 | kfree_skb(skb); |
| 324 | } |
| 325 | |
| 326 | /* |
| 327 | * State machine for state 3, Connected State. |
| 328 | * The handling of the timer(s) is in file lapb_timer.c |
| 329 | */ |
| 330 | static void lapb_state3_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
| 331 | struct lapb_frame *frame) |
| 332 | { |
| 333 | int queued = 0; |
| 334 | int modulus = (lapb->mode & LAPB_EXTENDED) ? LAPB_EMODULUS : |
| 335 | LAPB_SMODULUS; |
| 336 | |
| 337 | switch (frame->type) { |
| 338 | case LAPB_SABM: |
| 339 | #if LAPB_DEBUG > 1 |
| 340 | printk(KERN_DEBUG "lapb: (%p) S3 RX SABM(%d)\n", |
| 341 | lapb->dev, frame->pf); |
| 342 | #endif |
| 343 | if (lapb->mode & LAPB_EXTENDED) { |
| 344 | #if LAPB_DEBUG > 1 |
| 345 | printk(KERN_DEBUG "lapb: (%p) S3 TX DM(%d)\n", |
| 346 | lapb->dev, frame->pf); |
| 347 | #endif |
| 348 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 349 | LAPB_RESPONSE); |
| 350 | } else { |
| 351 | #if LAPB_DEBUG > 1 |
| 352 | printk(KERN_DEBUG "lapb: (%p) S3 TX UA(%d)\n", |
| 353 | lapb->dev, frame->pf); |
| 354 | #endif |
| 355 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 356 | LAPB_RESPONSE); |
| 357 | lapb_stop_t1timer(lapb); |
| 358 | lapb_stop_t2timer(lapb); |
| 359 | lapb->condition = 0x00; |
| 360 | lapb->n2count = 0; |
| 361 | lapb->vs = 0; |
| 362 | lapb->vr = 0; |
| 363 | lapb->va = 0; |
| 364 | lapb_requeue_frames(lapb); |
| 365 | } |
| 366 | break; |
| 367 | |
| 368 | case LAPB_SABME: |
| 369 | #if LAPB_DEBUG > 1 |
| 370 | printk(KERN_DEBUG "lapb: (%p) S3 RX SABME(%d)\n", |
| 371 | lapb->dev, frame->pf); |
| 372 | #endif |
| 373 | if (lapb->mode & LAPB_EXTENDED) { |
| 374 | #if LAPB_DEBUG > 1 |
| 375 | printk(KERN_DEBUG "lapb: (%p) S3 TX UA(%d)\n", |
| 376 | lapb->dev, frame->pf); |
| 377 | #endif |
| 378 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 379 | LAPB_RESPONSE); |
| 380 | lapb_stop_t1timer(lapb); |
| 381 | lapb_stop_t2timer(lapb); |
| 382 | lapb->condition = 0x00; |
| 383 | lapb->n2count = 0; |
| 384 | lapb->vs = 0; |
| 385 | lapb->vr = 0; |
| 386 | lapb->va = 0; |
| 387 | lapb_requeue_frames(lapb); |
| 388 | } else { |
| 389 | #if LAPB_DEBUG > 1 |
| 390 | printk(KERN_DEBUG "lapb: (%p) S3 TX DM(%d)\n", |
| 391 | lapb->dev, frame->pf); |
| 392 | #endif |
| 393 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 394 | LAPB_RESPONSE); |
| 395 | } |
| 396 | break; |
| 397 | |
| 398 | case LAPB_DISC: |
| 399 | #if LAPB_DEBUG > 1 |
| 400 | printk(KERN_DEBUG "lapb: (%p) S3 RX DISC(%d)\n", |
| 401 | lapb->dev, frame->pf); |
| 402 | #endif |
| 403 | #if LAPB_DEBUG > 0 |
| 404 | printk(KERN_DEBUG "lapb: (%p) S3 -> S0\n", |
| 405 | lapb->dev); |
| 406 | #endif |
| 407 | lapb_clear_queues(lapb); |
| 408 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 409 | LAPB_RESPONSE); |
| 410 | lapb_start_t1timer(lapb); |
| 411 | lapb_stop_t2timer(lapb); |
| 412 | lapb->state = LAPB_STATE_0; |
| 413 | lapb_disconnect_indication(lapb, LAPB_OK); |
| 414 | break; |
| 415 | |
| 416 | case LAPB_DM: |
| 417 | #if LAPB_DEBUG > 1 |
| 418 | printk(KERN_DEBUG "lapb: (%p) S3 RX DM(%d)\n", |
| 419 | lapb->dev, frame->pf); |
| 420 | #endif |
| 421 | #if LAPB_DEBUG > 0 |
| 422 | printk(KERN_DEBUG "lapb: (%p) S3 -> S0\n", |
| 423 | lapb->dev); |
| 424 | #endif |
| 425 | lapb_clear_queues(lapb); |
| 426 | lapb->state = LAPB_STATE_0; |
| 427 | lapb_start_t1timer(lapb); |
| 428 | lapb_stop_t2timer(lapb); |
| 429 | lapb_disconnect_indication(lapb, LAPB_NOTCONNECTED); |
| 430 | break; |
| 431 | |
| 432 | case LAPB_RNR: |
| 433 | #if LAPB_DEBUG > 1 |
| 434 | printk(KERN_DEBUG "lapb: (%p) S3 RX RNR(%d) R%d\n", |
| 435 | lapb->dev, frame->pf, frame->nr); |
| 436 | #endif |
| 437 | lapb->condition |= LAPB_PEER_RX_BUSY_CONDITION; |
| 438 | lapb_check_need_response(lapb, frame->cr, frame->pf); |
| 439 | if (lapb_validate_nr(lapb, frame->nr)) { |
| 440 | lapb_check_iframes_acked(lapb, frame->nr); |
| 441 | } else { |
| 442 | lapb->frmr_data = *frame; |
| 443 | lapb->frmr_type = LAPB_FRMR_Z; |
| 444 | lapb_transmit_frmr(lapb); |
| 445 | #if LAPB_DEBUG > 0 |
| 446 | printk(KERN_DEBUG "lapb: (%p) S3 -> S4\n", |
| 447 | lapb->dev); |
| 448 | #endif |
| 449 | lapb_start_t1timer(lapb); |
| 450 | lapb_stop_t2timer(lapb); |
| 451 | lapb->state = LAPB_STATE_4; |
| 452 | lapb->n2count = 0; |
| 453 | } |
| 454 | break; |
| 455 | |
| 456 | case LAPB_RR: |
| 457 | #if LAPB_DEBUG > 1 |
| 458 | printk(KERN_DEBUG "lapb: (%p) S3 RX RR(%d) R%d\n", |
| 459 | lapb->dev, frame->pf, frame->nr); |
| 460 | #endif |
| 461 | lapb->condition &= ~LAPB_PEER_RX_BUSY_CONDITION; |
| 462 | lapb_check_need_response(lapb, frame->cr, frame->pf); |
| 463 | if (lapb_validate_nr(lapb, frame->nr)) { |
| 464 | lapb_check_iframes_acked(lapb, frame->nr); |
| 465 | } else { |
| 466 | lapb->frmr_data = *frame; |
| 467 | lapb->frmr_type = LAPB_FRMR_Z; |
| 468 | lapb_transmit_frmr(lapb); |
| 469 | #if LAPB_DEBUG > 0 |
| 470 | printk(KERN_DEBUG "lapb: (%p) S3 -> S4\n", |
| 471 | lapb->dev); |
| 472 | #endif |
| 473 | lapb_start_t1timer(lapb); |
| 474 | lapb_stop_t2timer(lapb); |
| 475 | lapb->state = LAPB_STATE_4; |
| 476 | lapb->n2count = 0; |
| 477 | } |
| 478 | break; |
| 479 | |
| 480 | case LAPB_REJ: |
| 481 | #if LAPB_DEBUG > 1 |
| 482 | printk(KERN_DEBUG "lapb: (%p) S3 RX REJ(%d) R%d\n", |
| 483 | lapb->dev, frame->pf, frame->nr); |
| 484 | #endif |
| 485 | lapb->condition &= ~LAPB_PEER_RX_BUSY_CONDITION; |
| 486 | lapb_check_need_response(lapb, frame->cr, frame->pf); |
| 487 | if (lapb_validate_nr(lapb, frame->nr)) { |
| 488 | lapb_frames_acked(lapb, frame->nr); |
| 489 | lapb_stop_t1timer(lapb); |
| 490 | lapb->n2count = 0; |
| 491 | lapb_requeue_frames(lapb); |
| 492 | } else { |
| 493 | lapb->frmr_data = *frame; |
| 494 | lapb->frmr_type = LAPB_FRMR_Z; |
| 495 | lapb_transmit_frmr(lapb); |
| 496 | #if LAPB_DEBUG > 0 |
| 497 | printk(KERN_DEBUG "lapb: (%p) S3 -> S4\n", |
| 498 | lapb->dev); |
| 499 | #endif |
| 500 | lapb_start_t1timer(lapb); |
| 501 | lapb_stop_t2timer(lapb); |
| 502 | lapb->state = LAPB_STATE_4; |
| 503 | lapb->n2count = 0; |
| 504 | } |
| 505 | break; |
| 506 | |
| 507 | case LAPB_I: |
| 508 | #if LAPB_DEBUG > 1 |
| 509 | printk(KERN_DEBUG "lapb: (%p) S3 RX I(%d) S%d R%d\n", |
| 510 | lapb->dev, frame->pf, frame->ns, frame->nr); |
| 511 | #endif |
| 512 | if (!lapb_validate_nr(lapb, frame->nr)) { |
| 513 | lapb->frmr_data = *frame; |
| 514 | lapb->frmr_type = LAPB_FRMR_Z; |
| 515 | lapb_transmit_frmr(lapb); |
| 516 | #if LAPB_DEBUG > 0 |
| 517 | printk(KERN_DEBUG "lapb: (%p) S3 -> S4\n", |
| 518 | lapb->dev); |
| 519 | #endif |
| 520 | lapb_start_t1timer(lapb); |
| 521 | lapb_stop_t2timer(lapb); |
| 522 | lapb->state = LAPB_STATE_4; |
| 523 | lapb->n2count = 0; |
| 524 | break; |
| 525 | } |
| 526 | if (lapb->condition & LAPB_PEER_RX_BUSY_CONDITION) |
| 527 | lapb_frames_acked(lapb, frame->nr); |
| 528 | else |
| 529 | lapb_check_iframes_acked(lapb, frame->nr); |
| 530 | |
| 531 | if (frame->ns == lapb->vr) { |
| 532 | int cn; |
| 533 | cn = lapb_data_indication(lapb, skb); |
| 534 | queued = 1; |
| 535 | /* |
| 536 | * If upper layer has dropped the frame, we |
| 537 | * basically ignore any further protocol |
| 538 | * processing. This will cause the peer |
| 539 | * to re-transmit the frame later like |
| 540 | * a frame lost on the wire. |
| 541 | */ |
| 542 | if (cn == NET_RX_DROP) { |
| 543 | printk(KERN_DEBUG |
| 544 | "LAPB: rx congestion\n"); |
| 545 | break; |
| 546 | } |
| 547 | lapb->vr = (lapb->vr + 1) % modulus; |
| 548 | lapb->condition &= ~LAPB_REJECT_CONDITION; |
| 549 | if (frame->pf) |
| 550 | lapb_enquiry_response(lapb); |
| 551 | else { |
| 552 | if (!(lapb->condition & |
| 553 | LAPB_ACK_PENDING_CONDITION)) { |
| 554 | lapb->condition |= LAPB_ACK_PENDING_CONDITION; |
| 555 | lapb_start_t2timer(lapb); |
| 556 | } |
| 557 | } |
| 558 | } else { |
| 559 | if (lapb->condition & LAPB_REJECT_CONDITION) { |
| 560 | if (frame->pf) |
| 561 | lapb_enquiry_response(lapb); |
| 562 | } else { |
| 563 | #if LAPB_DEBUG > 1 |
| 564 | printk(KERN_DEBUG |
| 565 | "lapb: (%p) S3 TX REJ(%d) R%d\n", |
| 566 | lapb->dev, frame->pf, lapb->vr); |
| 567 | #endif |
| 568 | lapb->condition |= LAPB_REJECT_CONDITION; |
| 569 | lapb_send_control(lapb, LAPB_REJ, |
| 570 | frame->pf, |
| 571 | LAPB_RESPONSE); |
| 572 | lapb->condition &= ~LAPB_ACK_PENDING_CONDITION; |
| 573 | } |
| 574 | } |
| 575 | break; |
| 576 | |
| 577 | case LAPB_FRMR: |
| 578 | #if LAPB_DEBUG > 1 |
| 579 | printk(KERN_DEBUG "lapb: (%p) S3 RX FRMR(%d) %02X " |
| 580 | "%02X %02X %02X %02X\n", lapb->dev, frame->pf, |
| 581 | skb->data[0], skb->data[1], skb->data[2], |
| 582 | skb->data[3], skb->data[4]); |
| 583 | #endif |
| 584 | lapb_establish_data_link(lapb); |
| 585 | #if LAPB_DEBUG > 0 |
| 586 | printk(KERN_DEBUG "lapb: (%p) S3 -> S1\n", |
| 587 | lapb->dev); |
| 588 | #endif |
| 589 | lapb_requeue_frames(lapb); |
| 590 | lapb->state = LAPB_STATE_1; |
| 591 | break; |
| 592 | |
| 593 | case LAPB_ILLEGAL: |
| 594 | #if LAPB_DEBUG > 1 |
| 595 | printk(KERN_DEBUG "lapb: (%p) S3 RX ILLEGAL(%d)\n", |
| 596 | lapb->dev, frame->pf); |
| 597 | #endif |
| 598 | lapb->frmr_data = *frame; |
| 599 | lapb->frmr_type = LAPB_FRMR_W; |
| 600 | lapb_transmit_frmr(lapb); |
| 601 | #if LAPB_DEBUG > 0 |
| 602 | printk(KERN_DEBUG "lapb: (%p) S3 -> S4\n", lapb->dev); |
| 603 | #endif |
| 604 | lapb_start_t1timer(lapb); |
| 605 | lapb_stop_t2timer(lapb); |
| 606 | lapb->state = LAPB_STATE_4; |
| 607 | lapb->n2count = 0; |
| 608 | break; |
| 609 | } |
| 610 | |
| 611 | if (!queued) |
| 612 | kfree_skb(skb); |
| 613 | } |
| 614 | |
| 615 | /* |
| 616 | * State machine for state 4, Frame Reject State. |
| 617 | * The handling of the timer(s) is in file lapb_timer.c. |
| 618 | */ |
| 619 | static void lapb_state4_machine(struct lapb_cb *lapb, struct sk_buff *skb, |
| 620 | struct lapb_frame *frame) |
| 621 | { |
| 622 | switch (frame->type) { |
| 623 | case LAPB_SABM: |
| 624 | #if LAPB_DEBUG > 1 |
| 625 | printk(KERN_DEBUG "lapb: (%p) S4 RX SABM(%d)\n", |
| 626 | lapb->dev, frame->pf); |
| 627 | #endif |
| 628 | if (lapb->mode & LAPB_EXTENDED) { |
| 629 | #if LAPB_DEBUG > 1 |
| 630 | printk(KERN_DEBUG "lapb: (%p) S4 TX DM(%d)\n", |
| 631 | lapb->dev, frame->pf); |
| 632 | #endif |
| 633 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 634 | LAPB_RESPONSE); |
| 635 | } else { |
| 636 | #if LAPB_DEBUG > 1 |
| 637 | printk(KERN_DEBUG "lapb: (%p) S4 TX UA(%d)\n", |
| 638 | lapb->dev, frame->pf); |
| 639 | #endif |
| 640 | #if LAPB_DEBUG > 0 |
| 641 | printk(KERN_DEBUG "lapb: (%p) S4 -> S3\n", |
| 642 | lapb->dev); |
| 643 | #endif |
| 644 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 645 | LAPB_RESPONSE); |
| 646 | lapb_stop_t1timer(lapb); |
| 647 | lapb_stop_t2timer(lapb); |
| 648 | lapb->state = LAPB_STATE_3; |
| 649 | lapb->condition = 0x00; |
| 650 | lapb->n2count = 0; |
| 651 | lapb->vs = 0; |
| 652 | lapb->vr = 0; |
| 653 | lapb->va = 0; |
| 654 | lapb_connect_indication(lapb, LAPB_OK); |
| 655 | } |
| 656 | break; |
| 657 | |
| 658 | case LAPB_SABME: |
| 659 | #if LAPB_DEBUG > 1 |
| 660 | printk(KERN_DEBUG "lapb: (%p) S4 RX SABME(%d)\n", |
| 661 | lapb->dev, frame->pf); |
| 662 | #endif |
| 663 | if (lapb->mode & LAPB_EXTENDED) { |
| 664 | #if LAPB_DEBUG > 1 |
| 665 | printk(KERN_DEBUG "lapb: (%p) S4 TX UA(%d)\n", |
| 666 | lapb->dev, frame->pf); |
| 667 | #endif |
| 668 | #if LAPB_DEBUG > 0 |
| 669 | printk(KERN_DEBUG "lapb: (%p) S4 -> S3\n", |
| 670 | lapb->dev); |
| 671 | #endif |
| 672 | lapb_send_control(lapb, LAPB_UA, frame->pf, |
| 673 | LAPB_RESPONSE); |
| 674 | lapb_stop_t1timer(lapb); |
| 675 | lapb_stop_t2timer(lapb); |
| 676 | lapb->state = LAPB_STATE_3; |
| 677 | lapb->condition = 0x00; |
| 678 | lapb->n2count = 0; |
| 679 | lapb->vs = 0; |
| 680 | lapb->vr = 0; |
| 681 | lapb->va = 0; |
| 682 | lapb_connect_indication(lapb, LAPB_OK); |
| 683 | } else { |
| 684 | #if LAPB_DEBUG > 1 |
| 685 | printk(KERN_DEBUG "lapb: (%p) S4 TX DM(%d)\n", |
| 686 | lapb->dev, frame->pf); |
| 687 | #endif |
| 688 | lapb_send_control(lapb, LAPB_DM, frame->pf, |
| 689 | LAPB_RESPONSE); |
| 690 | } |
| 691 | break; |
| 692 | } |
| 693 | |
| 694 | kfree_skb(skb); |
| 695 | } |
| 696 | |
| 697 | /* |
| 698 | * Process an incoming LAPB frame |
| 699 | */ |
| 700 | void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *skb) |
| 701 | { |
| 702 | struct lapb_frame frame; |
| 703 | |
| 704 | if (lapb_decode(lapb, skb, &frame) < 0) { |
| 705 | kfree_skb(skb); |
| 706 | return; |
| 707 | } |
| 708 | |
| 709 | switch (lapb->state) { |
| 710 | case LAPB_STATE_0: |
| 711 | lapb_state0_machine(lapb, skb, &frame); break; |
| 712 | case LAPB_STATE_1: |
| 713 | lapb_state1_machine(lapb, skb, &frame); break; |
| 714 | case LAPB_STATE_2: |
| 715 | lapb_state2_machine(lapb, skb, &frame); break; |
| 716 | case LAPB_STATE_3: |
| 717 | lapb_state3_machine(lapb, skb, &frame); break; |
| 718 | case LAPB_STATE_4: |
| 719 | lapb_state4_machine(lapb, skb, &frame); break; |
| 720 | } |
| 721 | |
| 722 | lapb_kick(lapb); |
| 723 | } |