/*
* DLCI Implementation of Frame Relay protocol for Linux, according to
* RFC 1490. This generic device provides en/decapsulation for an
* underlying hardware driver. Routes & IPs are assigned to these
* interfaces. Requires 'dlcicfg' program to create usable
* interfaces, the initial one, 'dlci' is for IOCTL use only.
*
* Version: @(#)dlci.c 0.30 12 Sep 1996
*
* Author: Mike McLagan <mike.mclagan@linux.org>
*
* Changes:
*
* 0.15 Mike Mclagan Packet freeing, bug in kmalloc call
* DLCI_RET handling
* 0.20 Mike McLagan More conservative on which packets
* are returned for retry and whic are
* are dropped. If DLCI_RET_DROP is
* returned from the FRAD, the packet is
* sent back to Linux for re-transmission
* 0.25 Mike McLagan Converted to use SIOC IOCTL calls
* 0.30 Jim Freeman Fixed to allow IPX traffic
*
* This program 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.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/in.h>
#include <linux/malloc.h>
#include <linux/string.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/if_frad.h>
#include <net/sock.h>
static const char *devname = "dlci";
static const char *version = "DLCI driver v0.30, 12 Sep 1996, mike.mclagan@linux.org";
static struct device *open_dev[CONFIG_DLCI_COUNT];
static char *basename[16];
int dlci_init(struct device *dev);
/* allow FRAD's to register their name as a valid FRAD */
int register_frad(const char *name)
{
int i;
if (!name)
return(-EINVAL);
for (i=0;i<sizeof(basename) / sizeof(char *);i++)
{
if (!basename[i])
break;
/* take care of multiple registrations */
if (strcmp(basename[i], name) == 0)
return(0);
}
if (i == sizeof(basename) / sizeof(char *))
return(-EMLINK);
basename[i] = kmalloc(strlen(name) + 1, GFP_KERNEL);
if (!basename[i])
return(-ENOMEM);
strcpy(basename[i], name);
return(0);
}
int unregister_frad(const char *name)
{
int i;
if (!name)
return(-EINVAL);
for (i=0;i<sizeof(basename) / sizeof(char *);i++)
if (basename[i] && (strcmp(basename[i], name) == 0))
break;
if (i == sizeof(basename) / sizeof(char *))
return(-EINVAL);
kfree(basename[i]);
basename[i] = NULL;
return(0);
}
/*
* these encapsulate the RFC 1490 requirements as well as
* deal with packet transmission and reception, working with
* the upper network layers
*/
static int dlci_header(struct sk_buff *skb, struct device *dev,
unsigned short type, void *daddr, void *saddr,
unsigned len)
{
struct frhdr hdr;
struct dlci_local *dlp;
unsigned hlen;
char *dest;
dlp = dev->priv;
hdr.control = FRAD_I_UI;
switch(type)
{
case ETH_P_IP:
hdr.IP_NLPID = FRAD_P_IP;
hlen = sizeof(hdr.control) + sizeof(hdr.IP_NLPID);
break;
/* feel free to add other types, if necessary */
default:
hdr.pad = FRAD_P_PADDING;
hdr.NLPID = FRAD_P_SNAP;
memset(hdr.OUI, 0, sizeof(hdr.OUI));
hdr.PID = htons(type);
hlen = sizeof(hdr);
break;
}
dest = skb_push(skb, hlen);
if (!dest)
return(0);
memcpy(dest, &hdr, hlen);
return(hlen);
}
static void dlci_receive(struct sk_buff *skb, struct device *dev)
{
struct dlci_local *dlp;
struct frhdr *hdr;
int process, header;
dlp = dev->priv;
hdr = (struct frhdr *) skb->data;
process = 0;
header = 0;
skb->dev = dev;
if (hdr->control != FRAD_I_UI)
{
printk(KERN_NOTICE "%s: Invalid header flag 0x%02X.\n", dev->name, hdr->control);
dlp->stats.rx_errors++;
}
else
switch(hdr->IP_NLPID)
{
case FRAD_P_PADDING:
if (hdr->NLPID != FRAD_P_SNAP)
{
printk(KERN_NOTICE "%s: Unsupported NLPID 0x%02X.\n", dev->name, hdr->NLPID);
dlp->stats.rx_errors++;
break;
}
if (hdr->OUI[0] + hdr->OUI[1] + hdr->OUI[2] != 0)
{
printk(KERN_NOTICE "%s: Unsupported organizationally unique identifier 0x%02X-%02X-%02X.\n", dev->name, hdr->OUI[0], hdr->OUI[1], hdr->OUI[2]);
dlp->stats.rx_errors++;
break;
}
/* at this point, it's an EtherType frame */
header = sizeof(struct frhdr);
/* Already in network order ! */
skb->protocol = hdr->PID;
process = 1;
break;
case FRAD_P_IP:
header = sizeof(hdr->control) + sizeof(hdr->IP_NLPID);
skb->protocol = htons(ETH_P_IP);
process = 1;
break;
case FRAD_P_SNAP:
case FRAD_P_Q933:
case FRAD_P_CLNP:
printk(KERN_NOTICE "%s: Unsupported NLPID 0x%02X.\n", dev->name, hdr->pad);
dlp->stats.rx_errors++;
break;
default:
printk(KERN_NOTICE "%s: Invalid pad byte 0x%02X.\n", dev->name, hdr->pad);
dlp->stats.rx_errors++;
break;
}
if (process)
{
/* we've set up the protocol, so discard the header */
skb->mac.raw = skb->data;
skb_pull(skb, header);
netif_rx(skb);
dlp->stats.rx_packets++;
}
else
dev_kfree_skb(skb, FREE_WRITE);
}
static int dlci_transmit(struct sk_buff *skb, struct device *dev)
{
struct dlci_local *dlp;
int ret;
ret = 0;
if (!skb || !dev)
return(0);
if (dev->tbusy)
return(1);
dlp = dev->priv;
if (set_bit(0, (void*)&dev->tbusy) != 0)
printk(KERN_WARNING "%s: transmitter access conflict.\n", dev->name);
else
{
ret = dlp->slave->hard_start_xmit(skb, dlp->slave);
switch (ret)
{
case DLCI_RET_OK:
dlp->stats.tx_packets++;
ret = 0;
break;
case DLCI_RET_ERR:
dlp->stats.tx_errors++;
ret = 0;
break;
case DLCI_RET_DROP:
dlp->stats.tx_dropped++;
ret = 1;
break;
}
/* Alan Cox recommends always returning 0, and always freeing the packet */
/* experience suggest a slightly more conservative approach */
if (!ret)
dev_kfree_skb(skb, FREE_WRITE);
dev->tbusy = 0;
}
return(ret);
}
int dlci_config(struct device *dev, struct dlci_conf *conf, int get)
{
struct dlci_conf config;
struct dlci_local *dlp;
struct frad_local *flp;
int err;
dlp = dev->priv;
flp = dlp->slave->priv;
if (!get)
{
err = verify_area(VERIFY_READ, conf, sizeof(struct dlci_conf));
if (err)
return(err);
memcpy_fromfs(&config, conf, sizeof(struct dlci_conf));
if (config.flags & ~DLCI_VALID_FLAGS)
return(-EINVAL);
memcpy(&dlp->config, &config, sizeof(struct dlci_conf));
dlp->configured = 1;
}
err = (*flp->dlci_conf)(dlp->slave, dev, get);
if (err)
return(err);
if (get)
{
err = verify_area(VERIFY_WRITE, conf, sizeof(struct dlci_conf));
if (err)
return(err);
memcpy_tofs(conf, &dlp->config, sizeof(struct dlci_conf));
}
return(0);
}
int dlci_dev_ioctl(struct device *dev, struct ifreq *ifr, int cmd)
{
struct dlci_local *dlp;
int err, len;
if (!suser())
return(-EPERM);
dlp = dev->priv;
switch(cmd)
{
case DLCI_GET_SLAVE:
if (!*(short *)(dev->dev_addr))
return(-EINVAL);
len = strlen(dlp->slave->name) + 1;
err = verify_area(VERIFY_WRITE, ifr->ifr_slave, len);
if (err)
return err;
memcpy_tofs(ifr->ifr_slave, dlp->slave->name, len);
break;
case DLCI_GET_CONF:
case DLCI_SET_CONF:
if (!*(short *)(dev->dev_addr))
return(-EINVAL);
return(dlci_config(dev, (struct dlci_conf *) ifr->ifr_data, cmd == DLCI_GET_CONF));
break;
default:
return(-EOPNOTSUPP);
}
return(0);
}
static int dlci_change_mtu(struct device *dev, int new_mtu)
{
struct dlci_local *dlp;
dlp = dev->priv;
return((*dlp->slave->change_mtu)(dlp->slave, new_mtu));
}
static int dlci_open(struct device *dev)
{
struct dlci_local *dlp;
struct frad_local *flp;
int err;
dlp = dev->priv;
if (!*(short *)(dev->dev_addr))
return(-EINVAL);
if (!dlp->slave->start)
return(-ENOTCONN);
dev->flags = 0;
dev->tbusy = 0;
dev->interrupt = 0;
dev->start = 1;
flp = dlp->slave->priv;
err = (*flp->activate)(dlp->slave, dev);
if (err)
return(err);
return 0;
}
static int dlci_close(struct device *dev)
{
struct dlci_local *dlp;
struct frad_local *flp;
int err;
dlp = dev->priv;
flp = dlp->slave->priv;
err = (*flp->deactivate)(dlp->slave, dev);
dev->start = 0;
dev->tbusy = 1;
return 0;
}
static struct enet_statistics *dlci_get_stats(struct device *dev)
{
struct dlci_local *dlp;
dlp = dev->priv;
return(&dlp->stats);
}
int dlci_add(struct dlci_add *dlci)
{
struct device *master, *slave;
struct dlci_local *dlp;
struct frad_local *flp;
int err, i;
char buf[10];
/* validate slave device */
slave = dev_get(dlci->devname);
if (!slave)
return(-ENODEV);
if (slave->type != ARPHRD_FRAD)
return(-EINVAL);
/* check for registration */
for (i=0;i<sizeof(basename) / sizeof(char *); i++)
if ((basename[i]) &&
(strncmp(dlci->devname, basename[i], strlen(basename[i])) == 0) &&
(strlen(dlci->devname) > strlen(basename[i])))
break;
if (i == sizeof(basename) / sizeof(char *))
return(-EINVAL);
/* check for too many open devices : should this be dynamic ? */
for(i=0;i<CONFIG_DLCI_COUNT;i++)
if (!open_dev[i])
break;
if (i == CONFIG_DLCI_COUNT)
return(-ENOSPC); /* #### Alan: Comments on this?? */
/* create device name */
sprintf(buf, "%s%02i", devname, i);
master = kmalloc(sizeof(*master), GFP_KERNEL);
if (!master)
return(-ENOMEM);
memset(master, 0, sizeof(*master));
master->name = kmalloc(strlen(buf) + 1, GFP_KERNEL);
if (!master->name)
{
kfree(master);
return(-ENOMEM);
}
strcpy(master->name, buf);
master->init = dlci_init;
master->flags = 0;
err = register_netdev(master);
if (err < 0)
{
kfree(master->name);
kfree(master);
return(err);
}
*(short *)(master->dev_addr) = dlci->dlci;
dlp = (struct dlci_local *) master->priv;
dlp->slave = slave;
flp = slave->priv;
err = flp ? (*flp->assoc)(slave, master) : -EINVAL;
if (err < 0)
{
unregister_netdev(master);
kfree(master->priv);
kfree(master->name);
kfree(master);
return(err);
}
strcpy(dlci->devname, buf);
open_dev[i] = master;
MOD_INC_USE_COUNT;
return(0);
}
int dlci_del(struct dlci_add *dlci)
{
struct dlci_local *dlp;
struct frad_local *flp;
struct device *master, *slave;
int i, err;
/* validate slave device */
master = dev_get(dlci->devname);
if (!master)
return(-ENODEV);
if (master->start)
return(-EBUSY);
dlp = master->priv;
slave = dlp->slave;
flp = slave->priv;
err = (*flp->deassoc)(slave, master);
if (err)
return(err);
unregister_netdev(master);
for(i=0;i<CONFIG_DLCI_COUNT;i++)
if (master == open_dev[i])
break;
if (i<CONFIG_DLCI_COUNT)
open_dev[i] = NULL;
kfree(master->priv);
kfree(master->name);
kfree(master);
MOD_DEC_USE_COUNT;
return(0);
}
int dlci_ioctl(unsigned int cmd, void *arg)
{
int err;
struct dlci_add add;
if (!suser())
return(-EPERM);
err=verify_area(VERIFY_READ, arg, sizeof(struct dlci_add));
if (err)
return(err);
memcpy_fromfs(&add, arg, sizeof(struct dlci_add));
switch (cmd)
{
case SIOCADDDLCI:
err = verify_area(VERIFY_WRITE, arg, sizeof(struct dlci_add));
if (err)
return(err);
err = dlci_add(&add);
if (!err)
memcpy_tofs(arg, &add, sizeof(struct dlci_add));
break;
case SIOCDELDLCI:
err = dlci_del(&add);
break;
default:
err = -EINVAL;
}
return(err);
}
int dlci_init(struct device *dev)
{
struct dlci_local *dlp;
int i;
dev->priv = kmalloc(sizeof(struct dlci_local), GFP_KERNEL);
if (!dev->priv)
return(-ENOMEM);
memset(dev->priv, 0, sizeof(struct dlci_local));
dlp = dev->priv;
dev->flags = 0;
dev->open = dlci_open;
dev->stop = dlci_close;
dev->do_ioctl = dlci_dev_ioctl;
dev->hard_start_xmit = dlci_transmit;
dev->hard_header = dlci_header;
dev->get_stats = dlci_get_stats;
dev->change_mtu = dlci_change_mtu;
dlp->receive = dlci_receive;
dev->type = ARPHRD_DLCI;
dev->family = AF_INET;
dev->hard_header_len = sizeof(struct frhdr);
dev->pa_alen = sizeof(unsigned long);
dev->addr_len = sizeof(short);
memset(dev->dev_addr, 0, sizeof(dev->dev_addr));
dev->pa_addr = 0;
dev->pa_dstaddr = 0;
dev->pa_brdaddr = 0;
dev->pa_mask = 0;
for (i = 0; i < DEV_NUMBUFFS; i++)
skb_queue_head_init(&dev->buffs[i]);
return(0);
}
int dlci_setup(void)
{
int i;
printk("%s.\n", version);
for(i=0;i<CONFIG_DLCI_COUNT;i++)
open_dev[i] = NULL;
for(i=0;i<sizeof(basename) / sizeof(char *);i++)
basename[i] = NULL;
return(0);
}
#ifdef MODULE
extern int (*dlci_ioctl_hook)(unsigned int, void *);
int init_module(void)
{
dlci_ioctl_hook = dlci_ioctl;
return(dlci_setup());
}
void cleanup_module(void)
{
dlci_ioctl_hook = NULL;
}
#endif /* MODULE */
