350 lines
7.2 KiB
C
350 lines
7.2 KiB
C
/*
|
|
* 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)
|
|
{
|
|
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);
|