slip_kern.c

Go to the documentation of this file.

/*
 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL.
 */

#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <net_kern.h>
#include "slip.h"

struct slip_init {
    char *gate_addr;
};

static void slip_init(struct net_device *dev, void *data)
{
    struct uml_net_private *private;
    struct slip_data *spri;
    struct slip_init *init = data;

    private = netdev_priv(dev);
    spri = (struct slip_data *) private->user;

    memset(spri->name, 0, sizeof(spri->name));
    spri->addr = NULL;
    spri->gate_addr = init->gate_addr;
    spri->slave = -1;
    spri->dev = dev;

    slip_proto_init(&spri->slip);

    dev->hard_header_len = 0;
    dev->header_ops = NULL;
    dev->addr_len = 0;
    dev->type = ARPHRD_SLIP;
    dev->tx_queue_len = 256;
    dev->flags = IFF_NOARP;
    printk("SLIP backend - SLIP IP = %s\n", spri->gate_addr);
}

static unsigned short slip_protocol(struct sk_buff *skbuff)
{
    return htons(ETH_P_IP);
}

static int slip_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
    return slip_user_read(fd, skb_mac_header(skb), skb->dev->mtu,
                  (struct slip_data *) &lp->user);
}

static int slip_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
{
    return slip_user_write(fd, skb->data, skb->len,
                   (struct slip_data *) &lp->user);
}

static const struct net_kern_info slip_kern_info = {
    .init           = slip_init,
    .protocol       = slip_protocol,
    .read           = slip_read,
    .write          = slip_write,
};

static int slip_setup(char *str, char **mac_out, void *data)
{
    struct slip_init *init = data;

    *init = ((struct slip_init) { .gate_addr = NULL });

    if (str[0] != '\0')
        init->gate_addr = str;
    return 1;
}

static struct transport slip_transport = {
    .list       = LIST_HEAD_INIT(slip_transport.list),
    .name       = "slip",
    .setup      = slip_setup,
    .user       = &slip_user_info,
    .kern       = &slip_kern_info,
    .private_size   = sizeof(struct slip_data),
    .setup_size     = sizeof(struct slip_init),
};

static int register_slip(void)
{
    register_transport(&slip_transport);
    return 0;
}

late_initcall(register_slip);