451 lines
9.0 KiB
C
451 lines
9.0 KiB
C
/*
|
|
* LAPB release 002
|
|
*
|
|
* This code REQUIRES 2.1.15 or higher/ NET3.038
|
|
*
|
|
* This module:
|
|
* This module is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*
|
|
* History
|
|
* LAPB 001 Jonathan Naylor Started Coding
|
|
* LAPB 002 Jonathan Naylor New timer architecture.
|
|
* 2000-10-29 Henner Eisen lapb_data_indication() return status.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/types.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/in.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/string.h>
|
|
#include <linux/sockios.h>
|
|
#include <linux/net.h>
|
|
#include <linux/inet.h>
|
|
#include <linux/if_arp.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/slab.h>
|
|
#include <net/sock.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/system.h>
|
|
#include <linux/fcntl.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/stat.h>
|
|
#include <linux/init.h>
|
|
#include <net/lapb.h>
|
|
|
|
static LIST_HEAD(lapb_list);
|
|
static DEFINE_RWLOCK(lapb_list_lock);
|
|
|
|
/*
|
|
* Free an allocated lapb control block.
|
|
*/
|
|
static void lapb_free_cb(struct lapb_cb *lapb)
|
|
{
|
|
kfree(lapb);
|
|
}
|
|
|
|
static __inline__ void lapb_hold(struct lapb_cb *lapb)
|
|
{
|
|
atomic_inc(&lapb->refcnt);
|
|
}
|
|
|
|
static __inline__ void lapb_put(struct lapb_cb *lapb)
|
|
{
|
|
if (atomic_dec_and_test(&lapb->refcnt))
|
|
lapb_free_cb(lapb);
|
|
}
|
|
|
|
/*
|
|
* Socket removal during an interrupt is now safe.
|
|
*/
|
|
static void __lapb_remove_cb(struct lapb_cb *lapb)
|
|
{
|
|
if (lapb->node.next) {
|
|
list_del(&lapb->node);
|
|
lapb_put(lapb);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Add a socket to the bound sockets list.
|
|
*/
|
|
static void __lapb_insert_cb(struct lapb_cb *lapb)
|
|
{
|
|
list_add(&lapb->node, &lapb_list);
|
|
lapb_hold(lapb);
|
|
}
|
|
|
|
static struct lapb_cb *__lapb_devtostruct(struct net_device *dev)
|
|
{
|
|
struct list_head *entry;
|
|
struct lapb_cb *lapb, *use = NULL;
|
|
|
|
list_for_each(entry, &lapb_list) {
|
|
lapb = list_entry(entry, struct lapb_cb, node);
|
|
if (lapb->dev == dev) {
|
|
use = lapb;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (use)
|
|
lapb_hold(use);
|
|
|
|
return use;
|
|
}
|
|
|
|
static struct lapb_cb *lapb_devtostruct(struct net_device *dev)
|
|
{
|
|
struct lapb_cb *rc;
|
|
|
|
read_lock_bh(&lapb_list_lock);
|
|
rc = __lapb_devtostruct(dev);
|
|
read_unlock_bh(&lapb_list_lock);
|
|
|
|
return rc;
|
|
}
|
|
/*
|
|
* Create an empty LAPB control block.
|
|
*/
|
|
static struct lapb_cb *lapb_create_cb(void)
|
|
{
|
|
struct lapb_cb *lapb = kzalloc(sizeof(*lapb), GFP_ATOMIC);
|
|
|
|
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
skb_queue_head_init(&lapb->write_queue);
|
|
skb_queue_head_init(&lapb->ack_queue);
|
|
|
|
init_timer(&lapb->t1timer);
|
|
init_timer(&lapb->t2timer);
|
|
|
|
lapb->t1 = LAPB_DEFAULT_T1;
|
|
lapb->t2 = LAPB_DEFAULT_T2;
|
|
lapb->n2 = LAPB_DEFAULT_N2;
|
|
lapb->mode = LAPB_DEFAULT_MODE;
|
|
lapb->window = LAPB_DEFAULT_WINDOW;
|
|
lapb->state = LAPB_STATE_0;
|
|
atomic_set(&lapb->refcnt, 1);
|
|
out:
|
|
return lapb;
|
|
}
|
|
|
|
int lapb_register(struct net_device *dev, struct lapb_register_struct *callbacks)
|
|
{
|
|
struct lapb_cb *lapb;
|
|
int rc = LAPB_BADTOKEN;
|
|
|
|
write_lock_bh(&lapb_list_lock);
|
|
|
|
lapb = __lapb_devtostruct(dev);
|
|
if (lapb) {
|
|
lapb_put(lapb);
|
|
goto out;
|
|
}
|
|
|
|
lapb = lapb_create_cb();
|
|
rc = LAPB_NOMEM;
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
lapb->dev = dev;
|
|
lapb->callbacks = *callbacks;
|
|
|
|
__lapb_insert_cb(lapb);
|
|
|
|
lapb_start_t1timer(lapb);
|
|
|
|
rc = LAPB_OK;
|
|
out:
|
|
write_unlock_bh(&lapb_list_lock);
|
|
return rc;
|
|
}
|
|
|
|
int lapb_unregister(struct net_device *dev)
|
|
{
|
|
struct lapb_cb *lapb;
|
|
int rc = LAPB_BADTOKEN;
|
|
|
|
write_lock_bh(&lapb_list_lock);
|
|
lapb = __lapb_devtostruct(dev);
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
lapb_stop_t1timer(lapb);
|
|
lapb_stop_t2timer(lapb);
|
|
|
|
lapb_clear_queues(lapb);
|
|
|
|
__lapb_remove_cb(lapb);
|
|
|
|
lapb_put(lapb);
|
|
rc = LAPB_OK;
|
|
out:
|
|
write_unlock_bh(&lapb_list_lock);
|
|
return rc;
|
|
}
|
|
|
|
int lapb_getparms(struct net_device *dev, struct lapb_parms_struct *parms)
|
|
{
|
|
int rc = LAPB_BADTOKEN;
|
|
struct lapb_cb *lapb = lapb_devtostruct(dev);
|
|
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
parms->t1 = lapb->t1 / HZ;
|
|
parms->t2 = lapb->t2 / HZ;
|
|
parms->n2 = lapb->n2;
|
|
parms->n2count = lapb->n2count;
|
|
parms->state = lapb->state;
|
|
parms->window = lapb->window;
|
|
parms->mode = lapb->mode;
|
|
|
|
if (!timer_pending(&lapb->t1timer))
|
|
parms->t1timer = 0;
|
|
else
|
|
parms->t1timer = (lapb->t1timer.expires - jiffies) / HZ;
|
|
|
|
if (!timer_pending(&lapb->t2timer))
|
|
parms->t2timer = 0;
|
|
else
|
|
parms->t2timer = (lapb->t2timer.expires - jiffies) / HZ;
|
|
|
|
lapb_put(lapb);
|
|
rc = LAPB_OK;
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
int lapb_setparms(struct net_device *dev, struct lapb_parms_struct *parms)
|
|
{
|
|
int rc = LAPB_BADTOKEN;
|
|
struct lapb_cb *lapb = lapb_devtostruct(dev);
|
|
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
rc = LAPB_INVALUE;
|
|
if (parms->t1 < 1 || parms->t2 < 1 || parms->n2 < 1)
|
|
goto out_put;
|
|
|
|
if (lapb->state == LAPB_STATE_0) {
|
|
if (parms->mode & LAPB_EXTENDED) {
|
|
if (parms->window < 1 || parms->window > 127)
|
|
goto out_put;
|
|
} else {
|
|
if (parms->window < 1 || parms->window > 7)
|
|
goto out_put;
|
|
}
|
|
lapb->mode = parms->mode;
|
|
lapb->window = parms->window;
|
|
}
|
|
|
|
lapb->t1 = parms->t1 * HZ;
|
|
lapb->t2 = parms->t2 * HZ;
|
|
lapb->n2 = parms->n2;
|
|
|
|
rc = LAPB_OK;
|
|
out_put:
|
|
lapb_put(lapb);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
int lapb_connect_request(struct net_device *dev)
|
|
{
|
|
struct lapb_cb *lapb = lapb_devtostruct(dev);
|
|
int rc = LAPB_BADTOKEN;
|
|
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
rc = LAPB_OK;
|
|
if (lapb->state == LAPB_STATE_1)
|
|
goto out_put;
|
|
|
|
rc = LAPB_CONNECTED;
|
|
if (lapb->state == LAPB_STATE_3 || lapb->state == LAPB_STATE_4)
|
|
goto out_put;
|
|
|
|
lapb_establish_data_link(lapb);
|
|
|
|
#if LAPB_DEBUG > 0
|
|
printk(KERN_DEBUG "lapb: (%p) S0 -> S1\n", lapb->dev);
|
|
#endif
|
|
lapb->state = LAPB_STATE_1;
|
|
|
|
rc = LAPB_OK;
|
|
out_put:
|
|
lapb_put(lapb);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
int lapb_disconnect_request(struct net_device *dev)
|
|
{
|
|
struct lapb_cb *lapb = lapb_devtostruct(dev);
|
|
int rc = LAPB_BADTOKEN;
|
|
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
switch (lapb->state) {
|
|
case LAPB_STATE_0:
|
|
rc = LAPB_NOTCONNECTED;
|
|
goto out_put;
|
|
|
|
case LAPB_STATE_1:
|
|
#if LAPB_DEBUG > 1
|
|
printk(KERN_DEBUG "lapb: (%p) S1 TX DISC(1)\n", lapb->dev);
|
|
#endif
|
|
#if LAPB_DEBUG > 0
|
|
printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", lapb->dev);
|
|
#endif
|
|
lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
|
|
lapb->state = LAPB_STATE_0;
|
|
lapb_start_t1timer(lapb);
|
|
rc = LAPB_NOTCONNECTED;
|
|
goto out_put;
|
|
|
|
case LAPB_STATE_2:
|
|
rc = LAPB_OK;
|
|
goto out_put;
|
|
}
|
|
|
|
lapb_clear_queues(lapb);
|
|
lapb->n2count = 0;
|
|
lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND);
|
|
lapb_start_t1timer(lapb);
|
|
lapb_stop_t2timer(lapb);
|
|
lapb->state = LAPB_STATE_2;
|
|
|
|
#if LAPB_DEBUG > 1
|
|
printk(KERN_DEBUG "lapb: (%p) S3 DISC(1)\n", lapb->dev);
|
|
#endif
|
|
#if LAPB_DEBUG > 0
|
|
printk(KERN_DEBUG "lapb: (%p) S3 -> S2\n", lapb->dev);
|
|
#endif
|
|
|
|
rc = LAPB_OK;
|
|
out_put:
|
|
lapb_put(lapb);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
int lapb_data_request(struct net_device *dev, struct sk_buff *skb)
|
|
{
|
|
struct lapb_cb *lapb = lapb_devtostruct(dev);
|
|
int rc = LAPB_BADTOKEN;
|
|
|
|
if (!lapb)
|
|
goto out;
|
|
|
|
rc = LAPB_NOTCONNECTED;
|
|
if (lapb->state != LAPB_STATE_3 && lapb->state != LAPB_STATE_4)
|
|
goto out_put;
|
|
|
|
skb_queue_tail(&lapb->write_queue, skb);
|
|
lapb_kick(lapb);
|
|
rc = LAPB_OK;
|
|
out_put:
|
|
lapb_put(lapb);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
int lapb_data_received(struct net_device *dev, struct sk_buff *skb)
|
|
{
|
|
struct lapb_cb *lapb = lapb_devtostruct(dev);
|
|
int rc = LAPB_BADTOKEN;
|
|
|
|
if (lapb) {
|
|
lapb_data_input(lapb, skb);
|
|
lapb_put(lapb);
|
|
rc = LAPB_OK;
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
void lapb_connect_confirmation(struct lapb_cb *lapb, int reason)
|
|
{
|
|
if (lapb->callbacks.connect_confirmation)
|
|
lapb->callbacks.connect_confirmation(lapb->dev, reason);
|
|
}
|
|
|
|
void lapb_connect_indication(struct lapb_cb *lapb, int reason)
|
|
{
|
|
if (lapb->callbacks.connect_indication)
|
|
lapb->callbacks.connect_indication(lapb->dev, reason);
|
|
}
|
|
|
|
void lapb_disconnect_confirmation(struct lapb_cb *lapb, int reason)
|
|
{
|
|
if (lapb->callbacks.disconnect_confirmation)
|
|
lapb->callbacks.disconnect_confirmation(lapb->dev, reason);
|
|
}
|
|
|
|
void lapb_disconnect_indication(struct lapb_cb *lapb, int reason)
|
|
{
|
|
if (lapb->callbacks.disconnect_indication)
|
|
lapb->callbacks.disconnect_indication(lapb->dev, reason);
|
|
}
|
|
|
|
int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *skb)
|
|
{
|
|
if (lapb->callbacks.data_indication)
|
|
return lapb->callbacks.data_indication(lapb->dev, skb);
|
|
|
|
kfree_skb(skb);
|
|
return NET_RX_SUCCESS; /* For now; must be != NET_RX_DROP */
|
|
}
|
|
|
|
int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *skb)
|
|
{
|
|
int used = 0;
|
|
|
|
if (lapb->callbacks.data_transmit) {
|
|
lapb->callbacks.data_transmit(lapb->dev, skb);
|
|
used = 1;
|
|
}
|
|
|
|
return used;
|
|
}
|
|
|
|
EXPORT_SYMBOL(lapb_register);
|
|
EXPORT_SYMBOL(lapb_unregister);
|
|
EXPORT_SYMBOL(lapb_getparms);
|
|
EXPORT_SYMBOL(lapb_setparms);
|
|
EXPORT_SYMBOL(lapb_connect_request);
|
|
EXPORT_SYMBOL(lapb_disconnect_request);
|
|
EXPORT_SYMBOL(lapb_data_request);
|
|
EXPORT_SYMBOL(lapb_data_received);
|
|
|
|
static int __init lapb_init(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void __exit lapb_exit(void)
|
|
{
|
|
WARN_ON(!list_empty(&lapb_list));
|
|
}
|
|
|
|
MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>");
|
|
MODULE_DESCRIPTION("The X.25 Link Access Procedure B link layer protocol");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_init(lapb_init);
|
|
module_exit(lapb_exit);
|