- 根目录:
- drivers
- net
- wan
- dlci.c
/*
* 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 0.35 4 Jan 1997
*
* 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 which 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
* 0.35 Michael Elizabeth Fixed incorrect memcpy_fromfs
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/kernel.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/init.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/if_frad.h>
#include <linux/bitops.h>
#include <net/sock.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <asm/uaccess.h>
static const char version[] = "DLCI driver v0.35, 4 Jan 1997, mike.mclagan@linux.org";
static LIST_HEAD(dlci_devs);
static void dlci_setup(struct net_device *);
/*
* 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 net_device *dev,
unsigned short type, const void *daddr,
const void *saddr, unsigned len)
{
struct frhdr hdr;
unsigned int hlen;
char *dest;
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 net_device *dev)
{
struct frhdr *hdr;
int process, header;
if (!pskb_may_pull(skb, sizeof(*hdr))) {
netdev_notice(dev, "invalid data no header\n");
dev->stats.rx_errors++;
kfree_skb(skb);
return;
}
hdr = (struct frhdr *) skb->data;
process = 0;
header = 0;
skb->dev = dev;
if (hdr->control != FRAD_I_UI)
{
netdev_notice(dev, "Invalid header flag 0x%02X\n",
hdr->control);
dev->stats.rx_errors++;
}
else
switch (hdr->IP_NLPID)
{
case FRAD_P_PADDING:
if (hdr->NLPID != FRAD_P_SNAP)
{
netdev_notice(dev, "Unsupported NLPID 0x%02X\n",
hdr->NLPID);
dev->stats.rx_errors++;
break;
}
if (hdr->OUI[0] + hdr->OUI[1] + hdr->OUI[2] != 0)
{
netdev_notice(dev, "Unsupported organizationally unique identifier 0x%02X-%02X-%02X\n",
hdr->OUI[0],
hdr->OUI[1],
hdr->OUI[2]);
dev->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:
netdev_notice(dev, "Unsupported NLPID 0x%02X\n",
hdr->pad);
dev->stats.rx_errors++;
break;
default:
netdev_notice(dev, "Invalid pad byte 0x%02X\n",
hdr->pad);
dev->stats.rx_errors++;
break;
}
if (process)
{
/* we've set up the protocol, so discard the header */
skb_reset_mac_header(skb);
skb_pull(skb, header);
dev->stats.rx_bytes += skb->len;
netif_rx(skb);
dev->stats.rx_packets++;
}
else
dev_kfree_skb(skb);
}
static netdev_tx_t dlci_transmit(struct sk_buff *skb, struct net_device *dev)
{
struct dlci_local *dlp = netdev_priv(dev);
if (skb) {
struct netdev_queue *txq = skb_get_tx_queue(dev, skb);
netdev_start_xmit(skb, dlp->slave, txq, false);
}
return NETDEV_TX_OK;
}
static int dlci_config(struct net_device *dev, struct dlci_conf __user *conf, int get)
{
struct dlci_conf config;
struct dlci_local *dlp;
struct frad_local *flp;
int err;
dlp = netdev_priv(dev);
flp = netdev_priv(dlp->slave);
if (!get)
{
if (copy_from_user(&config, conf, sizeof(struct dlci_conf)))
return -EFAULT;
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)
{
if (copy_to_user(conf, &dlp->config, sizeof(struct dlci_conf)))
return -EFAULT;
}
return 0;
}
static int dlci_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
struct dlci_local *dlp;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
dlp = netdev_priv(dev);
switch (cmd)
{
case DLCI_GET_SLAVE:
if (!*(short *)(dev->dev_addr))
return -EINVAL;
strncpy(ifr->ifr_slave, dlp->slave->name, sizeof(ifr->ifr_slave));
break;
case DLCI_GET_CONF:
case DLCI_SET_CONF:
if (!*(short *)(dev->dev_addr))
return -EINVAL;
return dlci_config(dev, ifr->ifr_data, cmd == DLCI_GET_CONF);
default:
return -EOPNOTSUPP;
}
return 0;
}
static int dlci_change_mtu(struct net_device *dev, int new_mtu)
{
struct dlci_local *dlp = netdev_priv(dev);
return dev_set_mtu(dlp->slave, new_mtu);
}
static int dlci_open(struct net_device *dev)
{
struct dlci_local *dlp;
struct frad_local *flp;
int err;
dlp = netdev_priv(dev);
if (!*(short *)(dev->dev_addr))
return -EINVAL;
if (!netif_running(dlp->slave))
return -ENOTCONN;
flp = netdev_priv(dlp->slave);
err = (*flp->activate)(dlp->slave, dev);
if (err)
return err;
netif_start_queue(dev);
return 0;
}
static int dlci_close(struct net_device *dev)
{
struct dlci_local *dlp;
struct frad_local *flp;
int err;
netif_stop_queue(dev);
dlp = netdev_priv(dev);
flp = netdev_priv(dlp->slave);
err = (*flp->deactivate)(dlp->slave, dev);
return 0;
}
static int dlci_add(struct dlci_add *dlci)
{
struct net_device *master, *slave;
struct dlci_local *dlp;
struct frad_local *flp;
int err = -EINVAL;
/* validate slave device */
slave = dev_get_by_name(&init_net, dlci->devname);
if (!slave)
return -ENODEV;
if (slave->type != ARPHRD_FRAD || netdev_priv(slave) == NULL)
goto err1;
/* create device name */
master = alloc_netdev(sizeof(struct dlci_local), "dlci%d",
NET_NAME_UNKNOWN, dlci_setup);
if (!master) {
err = -ENOMEM;
goto err1;
}
/* make sure same slave not already registered */
rtnl_lock();
list_for_each_entry(dlp, &dlci_devs, list) {
if (dlp->slave == slave) {
err = -EBUSY;
goto err2;
}
}
*(short *)(master->dev_addr) = dlci->dlci;
dlp = netdev_priv(master);
dlp->slave = slave;
dlp->master = master;
flp = netdev_priv(slave);
err = (*flp->assoc)(slave, master);
if (err < 0)
goto err2;
err = register_netdevice(master);
if (err < 0)
goto err2;
strcpy(dlci->devname, master->name);
list_add(&dlp->list, &dlci_devs);
rtnl_unlock();
return 0;
err2:
rtnl_unlock();
free_netdev(master);
err1:
dev_put(slave);
return err;
}
static int dlci_del(struct dlci_add *dlci)
{
struct dlci_local *dlp;
struct frad_local *flp;
struct net_device *master, *slave;
int err;
bool found = false;
rtnl_lock();
/* validate slave device */
master = __dev_get_by_name(&init_net, dlci->devname);
if (!master) {
err = -ENODEV;
goto out;
}
list_for_each_entry(dlp, &dlci_devs, list) {
if (dlp->master == master) {
found = true;
break;
}
}
if (!found) {
err = -ENODEV;
goto out;
}
if (netif_running(master)) {
err = -EBUSY;
goto out;
}
dlp = netdev_priv(master);
slave = dlp->slave;
flp = netdev_priv(slave);
err = (*flp->deassoc)(slave, master);
if (!err) {
list_del(&dlp->list);
unregister_netdevice(master);
dev_put(slave);
}
out:
rtnl_unlock();
return err;
}
static int dlci_ioctl(unsigned int cmd, void __user *arg)
{
struct dlci_add add;
int err;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
if (copy_from_user(&add, arg, sizeof(struct dlci_add)))
return -EFAULT;
switch (cmd)
{
case SIOCADDDLCI:
err = dlci_add(&add);
if (!err)
if (copy_to_user(arg, &add, sizeof(struct dlci_add)))
return -EFAULT;
break;
case SIOCDELDLCI:
err = dlci_del(&add);
break;
default:
err = -EINVAL;
}
return err;
}
static const struct header_ops dlci_header_ops = {
.create = dlci_header,
};
static const struct net_device_ops dlci_netdev_ops = {
.ndo_open = dlci_open,
.ndo_stop = dlci_close,
.ndo_do_ioctl = dlci_dev_ioctl,
.ndo_start_xmit = dlci_transmit,
.ndo_change_mtu = dlci_change_mtu,
};
static void dlci_setup(struct net_device *dev)
{
struct dlci_local *dlp = netdev_priv(dev);
dev->flags = 0;
dev->header_ops = &dlci_header_ops;
dev->netdev_ops = &dlci_netdev_ops;
dev->destructor = free_netdev;
dlp->receive = dlci_receive;
dev->type = ARPHRD_DLCI;
dev->hard_header_len = sizeof(struct frhdr);
dev->addr_len = sizeof(short);
}
/* if slave is unregistering, then cleanup master */
static int dlci_dev_event(struct notifier_block *unused,
unsigned long event, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
if (dev_net(dev) != &init_net)
return NOTIFY_DONE;
if (event == NETDEV_UNREGISTER) {
struct dlci_local *dlp;
list_for_each_entry(dlp, &dlci_devs, list) {
if (dlp->slave == dev) {
list_del(&dlp->list);
unregister_netdevice(dlp->master);
dev_put(dlp->slave);
break;
}
}
}
return NOTIFY_DONE;
}
static struct notifier_block dlci_notifier = {
.notifier_call = dlci_dev_event,
};
static int __init init_dlci(void)
{
dlci_ioctl_set(dlci_ioctl);
register_netdevice_notifier(&dlci_notifier);
printk("%s.\n", version);
return 0;
}
static void __exit dlci_exit(void)
{
struct dlci_local *dlp, *nxt;
dlci_ioctl_set(NULL);
unregister_netdevice_notifier(&dlci_notifier);
rtnl_lock();
list_for_each_entry_safe(dlp, nxt, &dlci_devs, list) {
unregister_netdevice(dlp->master);
dev_put(dlp->slave);
}
rtnl_unlock();
}
module_init(init_dlci);
module_exit(dlci_exit);
MODULE_AUTHOR("Mike McLagan");
MODULE_DESCRIPTION("Frame Relay DLCI layer");
MODULE_LICENSE("GPL");