/*
* Generic HDLC support routines for Linux
*
* Copyright (C) 1999 - 2005 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.
*
* Currently supported:
* * raw IP-in-HDLC
* * Cisco HDLC
* * Frame Relay with ANSI or CCITT LMI (both user and network side)
* * PPP
* * X.25
*
* Use sethdlc utility to set line parameters, protocol and PVCs
*
* How does it work:
* - proto.open(), close(), start(), stop() calls are serialized.
* The order is: open, [ start, stop ... ] close ...
* - proto.start() and stop() are called with spin_lock_irq held.
*/
#include <linux/config.h>
#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>
static const char* version = "HDLC support module revision 1.18";
#undef DEBUG_LINK
static int hdlc_change_mtu(struct net_device *dev, int new_mtu)
{
if ((new_mtu < 68) || (new_mtu > HDLC_MAX_MTU))
return -EINVAL;
dev->mtu = new_mtu;
return 0;
}
static struct net_device_stats *hdlc_get_stats(struct net_device *dev)
{
return hdlc_stats(dev);
}
static int hdlc_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *p, struct net_device *orig_dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
if (hdlc->proto.netif_rx)
return hdlc->proto.netif_rx(skb);
hdlc->stats.rx_dropped++; /* Shouldn't happen */
dev_kfree_skb(skb);
return NET_RX_DROP;
}
static void __hdlc_set_carrier_on(struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
if (hdlc->proto.start)
return hdlc->proto.start(dev);
#ifdef DEBUG_LINK
if (netif_carrier_ok(dev))
printk(KERN_ERR "hdlc_set_carrier_on(): already on\n");
#endif
netif_carrier_on(dev);
}
static void __hdlc_set_carrier_off(struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
if (hdlc->proto.stop)
return hdlc->proto.stop(dev);
#ifdef DEBUG_LINK
if (!netif_carrier_ok(dev))
printk(KERN_ERR "hdlc_set_carrier_off(): already off\n");
#endif
netif_carrier_off(dev);
}
void hdlc_set_carrier(int on, struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
unsigned long flags;
on = on ? 1 : 0;
#ifdef DEBUG_LINK
printk(KERN_DEBUG "hdlc_set_carrier %i\n", on);
#endif
spin_lock_irqsave(&hdlc->state_lock, flags);
if (hdlc->carrier == on)
goto carrier_exit; /* no change in DCD line level */
#ifdef DEBUG_LINK
printk(KERN_INFO "%s: carrier %s\n", dev->name, on ? "ON" : "off");
#endif
hdlc->carrier = on;
if (!hdlc->open)
goto carrier_exit;
if (hdlc->carrier) {
printk(KERN_INFO "%s: Carrier detected\n", dev->name);
__hdlc_set_carrier_on(dev);
} else {
printk(KERN_INFO "%s: Carrier lost\n", dev->name);
__hdlc_set_carrier_off(dev);
}
carrier_exit:
spin_unlock_irqrestore(&hdlc->state_lock, flags);
}
/* Must be called by hardware driver when HDLC device is being opened */
int hdlc_open(struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
#ifdef DEBUG_LINK
printk(KERN_DEBUG "hdlc_open() carrier %i open %i\n",
hdlc->carrier, hdlc->open);
#endif
if (hdlc->proto.id == -1)
return -ENOSYS; /* no protocol attached */
if (hdlc->proto.open) {
int result = hdlc->proto.open(dev);
if (result)
return result;
}
spin_lock_irq(&hdlc->state_lock);
if (hdlc->carrier) {
printk(KERN_INFO "%s: Carrier detected\n", dev->name);
__hdlc_set_carrier_on(dev);
} else
printk(KERN_INFO "%s: No carrier\n", dev->name);
hdlc->open = 1;
spin_unlock_irq(&hdlc->state_lock);
return 0;
}
/* Must be called by hardware driver when HDLC device is being closed */
void hdlc_close(struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
#ifdef DEBUG_LINK
printk(KERN_DEBUG "hdlc_close() carrier %i open %i\n",
hdlc->carrier, hdlc->open);
#endif
spin_lock_irq(&hdlc->state_lock);
hdlc->open = 0;
if (hdlc->carrier)
__hdlc_set_carrier_off(dev);
spin_unlock_irq(&hdlc->state_lock);
if (hdlc->proto.close)
hdlc->proto.close(dev);
}
#ifndef CONFIG_HDLC_RAW
#define hdlc_raw_ioctl(dev, ifr) -ENOSYS
#endif
#ifndef CONFIG_HDLC_RAW_ETH
#define hdlc_raw_eth_ioctl(dev, ifr) -ENOSYS
#endif
#ifndef CONFIG_HDLC_PPP
#define hdlc_ppp_ioctl(dev, ifr) -ENOSYS
#endif
#ifndef CONFIG_HDLC_CISCO
#define hdlc_cisco_ioctl(dev, ifr) -ENOSYS
#endif
#ifndef CONFIG_HDLC_FR
#define hdlc_fr_ioctl(dev, ifr) -ENOSYS
#endif
#ifndef CONFIG_HDLC_X25
#define hdlc_x25_ioctl(dev, ifr) -ENOSYS
#endif
int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
unsigned int proto;
if (cmd != SIOCWANDEV)
return -EINVAL;
switch(ifr->ifr_settings.type) {
case IF_PROTO_HDLC:
case IF_PROTO_HDLC_ETH:
case IF_PROTO_PPP:
case IF_PROTO_CISCO:
case IF_PROTO_FR:
case IF_PROTO_X25:
proto = ifr->ifr_settings.type;
break;
default:
proto = hdlc->proto.id;
}
switch(proto) {
case IF_PROTO_HDLC: return hdlc_raw_ioctl(dev, ifr);
case IF_PROTO_HDLC_ETH: return hdlc_raw_eth_ioctl(dev, ifr);
case IF_PROTO_PPP: return hdlc_ppp_ioctl(dev, ifr);
case IF_PROTO_CISCO: return hdlc_cisco_ioctl(dev, ifr);
case IF_PROTO_FR: return hdlc_fr_ioctl(dev, ifr);
case IF_PROTO_X25: return hdlc_x25_ioctl(dev, ifr);
default: return -EINVAL;
}
}
static void hdlc_setup(struct net_device *dev)
{
hdlc_device *hdlc = dev_to_hdlc(dev);
dev->get_stats = hdlc_get_stats;
dev->change_mtu = hdlc_change_mtu;
dev->mtu = HDLC_MAX_MTU;
dev->type = ARPHRD_RAWHDLC;
dev->hard_header_len = 16;
dev->flags = IFF_POINTOPOINT | IFF_NOARP;
hdlc->proto.id = -1;
hdlc->proto.detach = NULL;
hdlc->carrier = 1;
hdlc->open = 0;
spin_lock_init(&hdlc->state_lock);
}
struct net_device *alloc_hdlcdev(void *priv)
{
struct net_device *dev;
dev = alloc_netdev(sizeof(hdlc_device), "hdlc%d", hdlc_setup);
if (dev)
dev_to_hdlc(dev)->priv = priv;
return dev;
}
int register_hdlc_device(struct net_device *dev)
{
int result = dev_alloc_name(dev, "hdlc%d");
if (result < 0)
return result;
result = register_netdev(dev);
if (result != 0)
return -EIO;
if (netif_carrier_ok(dev))
netif_carrier_off(dev); /* no carrier until DCD goes up */
return 0;
}
void unregister_hdlc_device(struct net_device *dev)
{
rtnl_lock();
hdlc_proto_detach(dev_to_hdlc(dev));
unregister_netdevice(dev);
rtnl_unlock();
}
MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
MODULE_DESCRIPTION("HDLC support module");
MODULE_LICENSE("GPL v2");
EXPORT_SYMBOL(hdlc_open);
EXPORT_SYMBOL(hdlc_close);
EXPORT_SYMBOL(hdlc_set_carrier);
EXPORT_SYMBOL(hdlc_ioctl);
EXPORT_SYMBOL(alloc_hdlcdev);
EXPORT_SYMBOL(register_hdlc_device);
EXPORT_SYMBOL(unregister_hdlc_device);
static struct packet_type hdlc_packet_type = {
.type = __constant_htons(ETH_P_HDLC),
.func = hdlc_rcv,
};
static int __init hdlc_module_init(void)
{
printk(KERN_INFO "%s\n", version);
dev_add_pack(&hdlc_packet_type);
return 0;
}
static void __exit hdlc_module_exit(void)
{
dev_remove_pack(&hdlc_packet_type);
}
module_init(hdlc_module_init);
module_exit(hdlc_module_exit);
