/*
* Generic HDLC support routines for Linux
* X.25 support
*
* Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License
* as published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/errno.h>
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/pkt_sched.h>
#include <linux/inetdevice.h>
#include <linux/lapb.h>
#include <linux/rtnetlink.h>
#include <linux/hdlc.h>
#include <net/x25device.h>
static int x25_ioctl(struct net_device *dev, struct ifreq *ifr);
/* These functions are callbacks called by LAPB layer */
static void x25_connect_disconnect(struct net_device *dev, int reason, int code)
{
struct sk_buff *skb;
unsigned char *ptr;
if ((skb = dev_alloc_skb(1)) == NULL) {
printk(KERN_ERR "%s: out of memory\n", dev->name);
return;
}
ptr = skb_put(skb, 1);
*ptr = code;
skb->protocol = x25_type_trans(skb, dev);
netif_rx(skb);
}
static void x25_connected(struct net_device *dev, int reason)
{
x25_connect_disconnect(dev, reason, 1);
}
static void x25_disconnected(struct net_device *dev, int reason)
{
x25_connect_disconnect(dev, reason, 2);
}
static int x25_data_indication(struct net_device *dev, struct sk_buff *skb)
{
unsigned char *ptr;
skb_push(skb, 1);
if (skb_cow(skb, 1))
return NET_RX_DROP;
ptr = skb->data;
*ptr = 0;
skb->protocol = x25_type_trans(skb, dev);
return netif_rx(skb);
}
static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
hdlc->xmit(skb, dev); /* Ignore return value :-( */
}
static int x25_xmit(struct sk_buff *skb, struct net_device *dev)
{
int result;
/* X.25 to LAPB */
switch (skb->data[0]) {
case 0: /* Data to be transmitted */
skb_pull(skb, 1);
if ((result = lapb_data_request(dev, skb)) != LAPB_OK)
dev_kfree_skb(skb);
return 0;
case 1:
if ((result = lapb_connect_request(dev))!= LAPB_OK) {
if (result == LAPB_CONNECTED)
/* Send connect confirm. msg to level 3 */
x25_connected(dev, 0);
else
printk(KERN_ERR "%s: LAPB connect request "
"failed, error code = %i\n",
dev->name, result);
}
break;
case 2:
if ((result = lapb_disconnect_request(dev)) != LAPB_OK) {
if (result == LAPB_NOTCONNECTED)
/* Send disconnect confirm. msg to level 3 */
x25_disconnected(dev, 0);
else
printk(KERN_ERR "%s: LAPB disconnect request "
"failed, error code = %i\n",
dev->name, result);
}
break;
default: /* to be defined */
break;
}
dev_kfree_skb(skb);
return 0;
}
static int x25_open(struct net_device *dev)
{
struct lapb_register_struct cb;
int result;
cb.connect_confirmation = x25_connected;
cb.connect_indication = x25_connected;
cb.disconnect_confirmation = x25_disconnected;
cb.disconnect_indication = x25_disconnected;
cb.data_indication = x25_data_indication;
cb.data_transmit = x25_data_transmit;
result = lapb_register(dev, &cb);
if (result != LAPB_OK)
return result;
return 0;
}
static void x25_close(struct net_device *dev)
{
lapb_unregister(dev);
}
static int x25_rx(struct sk_buff *skb)
{
struct hdlc_device_desc *desc = dev_to_desc(skb->dev);
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
desc->stats.rx_dropped++;
return NET_RX_DROP;
}
if (lapb_data_received(skb->dev, skb) == LAPB_OK)
return NET_RX_SUCCESS;
desc->stats.rx_errors++;
dev_kfree_skb_any(skb);
return NET_RX_DROP;
}
static struct hdlc_proto proto = {
.open = x25_open,
.close = x25_close,
.ioctl = x25_ioctl,
.module = THIS_MODULE,
};
static int x25_ioctl(struct net_device *dev, struct ifreq *ifr)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
int result;
switch (ifr->ifr_settings.type) {
case IF_GET_PROTO:
if (dev_to_hdlc(dev)->proto != &proto)
return -EINVAL;
ifr->ifr_settings.type = IF_PROTO_X25;
return 0; /* return protocol only, no settable parameters */
case IF_PROTO_X25:
if(!capable(CAP_NET_ADMIN))
return -EPERM;
if(dev->flags & IFF_UP)
return -EBUSY;
result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
if (result)
return result;
if ((result = attach_hdlc_protocol(dev, &proto,
x25_rx, 0)) != 0)
return result;
dev->hard_start_xmit = x25_xmit;
dev->hard_header = NULL;
dev->type = ARPHRD_X25;
dev->addr_len = 0;
netif_dormant_off(dev);
return 0;
}
return -EINVAL;
}
static int __init mod_init(void)
{
register_hdlc_protocol(&proto);
return 0;
}
static void __exit mod_exit(void)
{
unregister_hdlc_protocol(&proto);
}
module_init(mod_init);
module_exit(mod_exit);
MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
MODULE_DESCRIPTION("X.25 protocol support for generic HDLC");
MODULE_LICENSE("GPL v2");
