diff options
Diffstat (limited to 'net/lapb/lapb_iface.c')
| -rw-r--r-- | net/lapb/lapb_iface.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/net/lapb/lapb_iface.c b/net/lapb/lapb_iface.c new file mode 100644 index 0000000..aea6616 --- /dev/null +++ b/net/lapb/lapb_iface.c @@ -0,0 +1,449 @@ +/* + * 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 <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 struct list_head lapb_list = LIST_HEAD_INIT(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 = kmalloc(sizeof(*lapb), GFP_ATOMIC); + + + if (!lapb) + goto out; + + memset(lapb, 0x00, sizeof(*lapb)); + + 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) && + (parms->window < 1 || parms->window > 127)) || + (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_CN_HIGH; /* 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); |
