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 Naylor Started Coding |
| 14 | * LAPB 002 Jonathan Naylor New timer architecture. |
| 15 | * 2000-10-29 Henner Eisen lapb_data_indication() return status. |
| 16 | */ |
YOSHIFUJI Hideaki | 56d6c3d | 2007-02-09 23:24:59 +0900 | [diff] [blame] | 17 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Denis Cheng | 14d0e7b | 2007-12-07 00:50:15 -0800 | [diff] [blame^] | 42 | static LIST_HEAD(lapb_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | static DEFINE_RWLOCK(lapb_list_lock); |
| 44 | |
| 45 | /* |
YOSHIFUJI Hideaki | 56d6c3d | 2007-02-09 23:24:59 +0900 | [diff] [blame] | 46 | * Free an allocated lapb control block. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | { |
Panagiotis Issaris | 0da974f | 2006-07-21 14:51:30 -0700 | [diff] [blame] | 118 | struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | |
| 120 | |
| 121 | if (!lapb) |
| 122 | goto out; |
| 123 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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) { |
Diego Calleja | 558e10a | 2006-08-05 21:15:58 -0700 | [diff] [blame] | 241 | if (parms->mode & LAPB_EXTENDED) { |
| 242 | if (parms->window < 1 || parms->window > 127) |
| 243 | goto out_put; |
| 244 | } else { |
| 245 | if (parms->window < 1 || parms->window > 7) |
| 246 | goto out_put; |
| 247 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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); |
YOSHIFUJI Hideaki | 56d6c3d | 2007-02-09 23:24:59 +0900 | [diff] [blame] | 410 | return NET_RX_CN_HIGH; /* For now; must be != NET_RX_DROP */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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); |