/*
* Generic HDLC support routines for Linux
* HDLC Ethernet emulation support
*
* Copyright (C) 2002-2006 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/random.h>
#include <linux/inetdevice.h>
#include <linux/lapb.h>
#include <linux/rtnetlink.h>
#include <linux/etherdevice.h>
#include <linux/hdlc.h>
static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr);
static int eth_tx(struct sk_buff *skb, struct net_device *dev)
{
int pad = ETH_ZLEN - skb->len;
if (pad > 0) { /* Pad the frame with zeros */
int len = skb->len;
if (skb_tailroom(skb) < pad)
if (pskb_expand_head(skb, 0, pad, GFP_ATOMIC)) {
hdlc_stats(dev)->tx_dropped++;
dev_kfree_skb(skb);
return 0;
}
skb_put(skb, pad);
memset(skb->data + len, 0, pad);
}
return dev_to_hdlc(dev)->xmit(skb, dev);
}
static struct hdlc_proto proto = {
.type_trans = eth_type_trans,
.ioctl = raw_eth_ioctl,
.module = THIS_MODULE,
};
static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
{
raw_hdlc_proto __user *raw_s = ifr->ifr_settings.ifs_ifsu.raw_hdlc;
const size_t size = sizeof(raw_hdlc_proto);
raw_hdlc_proto new_settings;
hdlc_device *hdlc = dev_to_hdlc(dev);
int result;
void *old_ch_mtu;
int old_qlen;
switch (ifr->ifr_settings.type) {
case IF_GET_PROTO:
if (dev_to_hdlc(dev)->proto != &proto)
return -EINVAL;
ifr->ifr_settings.type = IF_PROTO_HDLC_ETH;
if (ifr->ifr_settings.size < size) {
ifr->ifr_settings.size = size; /* data size wanted */
return -ENOBUFS;
}
if (copy_to_user(raw_s, hdlc->state, size))
return -EFAULT;
return 0;
case IF_PROTO_HDLC_ETH:
if (!capable(CAP_NET_ADMIN))
return -EPERM;
if (dev->flags & IFF_UP)
return -EBUSY;
if (copy_from_user(&new_settings, raw_s, size))
return -EFAULT;
if (new_settings.encoding == ENCODING_DEFAULT)
new_settings.encoding = ENCODING_NRZ;
if (new_settings.parity == PARITY_DEFAULT)
new_settings.parity = PARITY_CRC16_PR1_CCITT;
result = hdlc->attach(dev, new_settings.encoding,
new_settings.parity);
if (result)
return result;
result = attach_hdlc_protocol(dev, &proto, NULL,
sizeof(raw_hdlc_proto));
if (result)
return result;
memcpy(hdlc->state, &new_settings, size);
dev->hard_start_xmit = eth_tx;
old_ch_mtu = dev->change_mtu;
old_qlen = dev->tx_queue_len;
ether_setup(dev);
dev->change_mtu = old_ch_mtu;
dev->tx_queue_len = old_qlen;
memcpy(dev->dev_addr, "\x00\x01", 2);
get_random_bytes(dev->dev_addr + 2, ETH_ALEN - 2);
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("Ethernet encapsulation support for generic HDLC");
MODULE_LICENSE("GPL v2");
