Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 883 insertions, 0 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
new file mode 100644
index 000000000000..7bfee366297b
--- /dev/null
+++ b/drivers/net/tun.c
@@ -0,0 +1,883 @@
+/*
+ *  TUN - Universal TUN/TAP device driver.
+ *  Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
+ *
+ *  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.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *  GNU General Public License for more details.
+ *
+ *  $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
+ */
+
+/*
+ *  Changes:
+ *
+ *  Mark Smith <markzzzsmith@yahoo.com.au>
+ *   Use random_ether_addr() for tap MAC address.
+ *
+ *  Harald Roelle <harald.roelle@ifi.lmu.de>  2004/04/20
+ *    Fixes in packet dropping, queue length setting and queue wakeup.
+ *    Increased default tx queue length.
+ *    Added ethtool API.
+ *    Minor cleanups
+ *
+ *  Daniel Podlejski <underley@underley.eu.org>
+ *    Modifications for 2.3.99-pre5 kernel.
+ */
+
+#define DRV_NAME        "tun"
+#define DRV_VERSION     "1.6"
+#define DRV_DESCRIPTION "Universal TUN/TAP device driver"
+#define DRV_COPYRIGHT   "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/slab.h>
+#include <linux/poll.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/miscdevice.h>
+#include <linux/ethtool.h>
+#include <linux/rtnetlink.h>
+#include <linux/if.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/if_tun.h>
+#include <linux/crc32.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+
+#ifdef TUN_DEBUG
+static int debug;
+#endif
+
+/* Network device part of the driver */
+
+static LIST_HEAD(tun_dev_list);
+static struct ethtool_ops tun_ethtool_ops;
+
+/* Net device open. */
+static int tun_net_open(struct net_device *dev)
+{
+        netif_start_queue(dev);
+        return 0;
+}
+
+/* Net device close. */
+static int tun_net_close(struct net_device *dev)
+{
+        netif_stop_queue(dev);
+        return 0;
+}
+
+/* Net device start xmit */
+static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+
+        DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
+
+        /* Drop packet if interface is not attached */
+        if (!tun->attached)
+                goto drop;
+
+        /* Packet dropping */
+        if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
+                if (!(tun->flags & TUN_ONE_QUEUE)) {
+                        /* Normal queueing mode. */
+                        /* Packet scheduler handles dropping of further packets. */
+                        netif_stop_queue(dev);
+
+                        /* We won't see all dropped packets individually, so overrun
+                         * error is more appropriate. */
+                        tun->stats.tx_fifo_errors++;
+                } else {
+                        /* Single queue mode.
+                         * Driver handles dropping of all packets itself. */
+                        goto drop;
+                }
+        }
+
+        /* Queue packet */
+        skb_queue_tail(&tun->readq, skb);
+        dev->trans_start = jiffies;
+
+        /* Notify and wake up reader process */
+        if (tun->flags & TUN_FASYNC)
+                kill_fasync(&tun->fasync, SIGIO, POLL_IN);
+        wake_up_interruptible(&tun->read_wait);
+        return 0;
+
+drop:
+        tun->stats.tx_dropped++;
+        kfree_skb(skb);
+        return 0;
+}
+
+/** Add the specified Ethernet address to this multicast filter. */
+static void
+add_multi(u32* filter, const u8* addr)
+{
+        int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
+        filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
+}
+
+/** Remove the specified Ethernet addres from this multicast filter. */
+static void
+del_multi(u32* filter, const u8* addr)
+{
+        int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
+        filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31));
+}
+
+/** Update the list of multicast groups to which the network device belongs.
+ * This list is used to filter packets being sent from the character device to
+ * the network device. */
+static void
+tun_net_mclist(struct net_device *dev)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+        const struct dev_mc_list *mclist;
+        int i;
+        DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n",
+                        dev->name, dev->mc_count);
+        memset(tun->chr_filter, 0, sizeof tun->chr_filter);
+        for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL;
+                        i++, mclist = mclist->next) {
+                add_multi(tun->net_filter, mclist->dmi_addr);
+                DBG(KERN_DEBUG "%s: tun_net_mclist: %x:%x:%x:%x:%x:%x\n",
+                                dev->name,
+                                mclist->dmi_addr[0], mclist->dmi_addr[1], mclist->dmi_addr[2],
+                                mclist->dmi_addr[3], mclist->dmi_addr[4], mclist->dmi_addr[5]);
+        }
+}
+
+static struct net_device_stats *tun_net_stats(struct net_device *dev)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+        return &tun->stats;
+}
+
+/* Initialize net device. */
+static void tun_net_init(struct net_device *dev)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+   
+        switch (tun->flags & TUN_TYPE_MASK) {
+        case TUN_TUN_DEV:
+                /* Point-to-Point TUN Device */
+                dev->hard_header_len = 0;
+                dev->addr_len = 0;
+                dev->mtu = 1500;
+
+                /* Zero header length */
+                dev->type = ARPHRD_NONE; 
+                dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
+                dev->tx_queue_len = TUN_READQ_SIZE;  /* We prefer our own queue length */
+                break;
+
+        case TUN_TAP_DEV:
+                /* Ethernet TAP Device */
+                dev->set_multicast_list = tun_net_mclist;
+
+                ether_setup(dev);
+                random_ether_addr(dev->dev_addr);
+                dev->tx_queue_len = TUN_READQ_SIZE;  /* We prefer our own queue length */
+                break;
+        }
+}
+
+/* Character device part */
+
+/* Poll */
+static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
+{  
+        struct tun_struct *tun = file->private_data;
+        unsigned int mask = POLLOUT | POLLWRNORM;
+
+        if (!tun)
+                return -EBADFD;
+
+        DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
+
+        poll_wait(file, &tun->read_wait, wait);
+ 
+        if (skb_queue_len(&tun->readq))
+                mask |= POLLIN | POLLRDNORM;
+
+        return mask;
+}
+
+/* Get packet from user space buffer */
+static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
+{
+        struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
+        struct sk_buff *skb;
+        size_t len = count, align = 0;
+
+        if (!(tun->flags & TUN_NO_PI)) {
+                if ((len -= sizeof(pi)) > count)
+                        return -EINVAL;
+
+                if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
+                        return -EFAULT;
+        }
+
+        if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV)
+                align = NET_IP_ALIGN;
+ 
+        if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
+                tun->stats.rx_dropped++;
+                return -ENOMEM;
+        }
+
+        if (align)
+                skb_reserve(skb, align);
+        if (memcpy_fromiovec(skb_put(skb, len), iv, len))
+                return -EFAULT;
+
+        skb->dev = tun->dev;
+        switch (tun->flags & TUN_TYPE_MASK) {
+        case TUN_TUN_DEV:
+                skb->mac.raw = skb->data;
+                skb->protocol = pi.proto;
+                break;
+        case TUN_TAP_DEV:
+                skb->protocol = eth_type_trans(skb, tun->dev);
+                break;
+        };
+
+        if (tun->flags & TUN_NOCHECKSUM)
+                skb->ip_summed = CHECKSUM_UNNECESSARY;
+ 
+        netif_rx_ni(skb);
+        tun->dev->last_rx = jiffies;
+   
+        tun->stats.rx_packets++;
+        tun->stats.rx_bytes += len;
+
+        return count;
+} 
+
+static inline size_t iov_total(const struct iovec *iv, unsigned long count)
+{
+        unsigned long i;
+        size_t len;
+
+        for (i = 0, len = 0; i < count; i++) 
+                len += iv[i].iov_len;
+
+        return len;
+}
+
+/* Writev */
+static ssize_t tun_chr_writev(struct file * file, const struct iovec *iv, 
+                              unsigned long count, loff_t *pos)
+{
+        struct tun_struct *tun = file->private_data;
+
+        if (!tun)
+                return -EBADFD;
+
+        DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
+
+        return tun_get_user(tun, (struct iovec *) iv, iov_total(iv, count));
+}
+
+/* Write */
+static ssize_t tun_chr_write(struct file * file, const char __user * buf, 
+                             size_t count, loff_t *pos)
+{
+        struct iovec iv = { (void __user *) buf, count };
+        return tun_chr_writev(file, &iv, 1, pos);
+}
+
+/* Put packet to the user space buffer */
+static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
+                                       struct sk_buff *skb,
+                                       struct iovec *iv, int len)
+{
+        struct tun_pi pi = { 0, skb->protocol };
+        ssize_t total = 0;
+
+        if (!(tun->flags & TUN_NO_PI)) {
+                if ((len -= sizeof(pi)) < 0)
+                        return -EINVAL;
+
+                if (len < skb->len) {
+                        /* Packet will be striped */
+                        pi.flags |= TUN_PKT_STRIP;
+                }
+ 
+                if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
+                        return -EFAULT;
+                total += sizeof(pi);
+        }       
+
+        len = min_t(int, skb->len, len);
+
+        skb_copy_datagram_iovec(skb, 0, iv, len);
+        total += len;
+
+        tun->stats.tx_packets++;
+        tun->stats.tx_bytes += len;
+
+        return total;
+}
+
+/* Readv */
+static ssize_t tun_chr_readv(struct file *file, const struct iovec *iv,
+                            unsigned long count, loff_t *pos)
+{
+        struct tun_struct *tun = file->private_data;
+        DECLARE_WAITQUEUE(wait, current);
+        struct sk_buff *skb;
+        ssize_t len, ret = 0;
+
+        if (!tun)
+                return -EBADFD;
+
+        DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
+
+        len = iov_total(iv, count);
+        if (len < 0)
+                return -EINVAL;
+
+        add_wait_queue(&tun->read_wait, &wait);
+        while (len) {
+                const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+                u8 addr[ ETH_ALEN];
+                int bit_nr;
+
+                current->state = TASK_INTERRUPTIBLE;
+
+                /* Read frames from the queue */
+                if (!(skb=skb_dequeue(&tun->readq))) {
+                        if (file->f_flags & O_NONBLOCK) {
+                                ret = -EAGAIN;
+                                break;
+                        }
+                        if (signal_pending(current)) {
+                                ret = -ERESTARTSYS;
+                                break;
+                        }
+
+                        /* Nothing to read, let's sleep */
+                        schedule();
+                        continue;
+                }
+                netif_wake_queue(tun->dev);
+
+                /** Decide whether to accept this packet. This code is designed to
+                 * behave identically to an Ethernet interface. Accept the packet if
+                 * - we are promiscuous.
+                 * - the packet is addressed to us.
+                 * - the packet is broadcast.
+                 * - the packet is multicast and
+                 *   - we are multicast promiscous.
+                 *   - we belong to the multicast group.
+                 */
+                memcpy(addr, skb->data,
+                       min_t(size_t, sizeof addr, skb->len));
+                bit_nr = ether_crc(sizeof addr, addr) >> 26;
+                if ((tun->if_flags & IFF_PROMISC) ||
+                                memcmp(addr, tun->dev_addr, sizeof addr) == 0 ||
+                                memcmp(addr, ones, sizeof addr) == 0 ||
+                                (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) ||
+                                  (addr[0] == 0x33 && addr[1] == 0x33)) &&
+                                 ((tun->if_flags & IFF_ALLMULTI) ||
+                                  (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) {
+                        DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %x:%x:%x:%x:%x:%x\n",
+                                        tun->dev->name, addr[0], addr[1], addr[2],
+                                        addr[3], addr[4], addr[5]);
+                        ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
+                        kfree_skb(skb);
+                        break;
+                } else {
+                        DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %x:%x:%x:%x:%x:%x\n",
+                                        tun->dev->name, addr[0], addr[1], addr[2],
+                                        addr[3], addr[4], addr[5]);
+                        kfree_skb(skb);
+                        continue;
+                }
+        }
+
+        current->state = TASK_RUNNING;
+        remove_wait_queue(&tun->read_wait, &wait);
+
+        return ret;
+}
+
+/* Read */
+static ssize_t tun_chr_read(struct file * file, char __user * buf, 
+                            size_t count, loff_t *pos)
+{
+        struct iovec iv = { buf, count };
+        return tun_chr_readv(file, &iv, 1, pos);
+}
+
+static void tun_setup(struct net_device *dev)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+
+        skb_queue_head_init(&tun->readq);
+        init_waitqueue_head(&tun->read_wait);
+
+        tun->owner = -1;
+
+        SET_MODULE_OWNER(dev);
+        dev->open = tun_net_open;
+        dev->hard_start_xmit = tun_net_xmit;
+        dev->stop = tun_net_close;
+        dev->get_stats = tun_net_stats;
+        dev->ethtool_ops = &tun_ethtool_ops;
+        dev->destructor = free_netdev;
+}
+
+static struct tun_struct *tun_get_by_name(const char *name)
+{
+        struct tun_struct *tun;
+
+        ASSERT_RTNL();
+        list_for_each_entry(tun, &tun_dev_list, list) {
+                if (!strncmp(tun->dev->name, name, IFNAMSIZ))
+                    return tun;
+        }
+
+        return NULL;
+}
+
+static int tun_set_iff(struct file *file, struct ifreq *ifr)
+{
+        struct tun_struct *tun;
+        struct net_device *dev;
+        int err;
+
+        tun = tun_get_by_name(ifr->ifr_name);
+        if (tun) {
+                if (tun->attached)
+                        return -EBUSY;
+
+                /* Check permissions */
+                if (tun->owner != -1 &&
+                    current->euid != tun->owner && !capable(CAP_NET_ADMIN))
+                        return -EPERM;
+        } 
+        else if (__dev_get_by_name(ifr->ifr_name)) 
+                return -EINVAL;
+        else {
+                char *name;
+                unsigned long flags = 0;
+
+                err = -EINVAL;
+
+                /* Set dev type */
+                if (ifr->ifr_flags & IFF_TUN) {
+                        /* TUN device */
+                        flags |= TUN_TUN_DEV;
+                        name = "tun%d";
+                } else if (ifr->ifr_flags & IFF_TAP) {
+                        /* TAP device */
+                        flags |= TUN_TAP_DEV;
+                        name = "tap%d";
+                } else 
+                        goto failed;
+   
+                if (*ifr->ifr_name)
+                        name = ifr->ifr_name;
+
+                dev = alloc_netdev(sizeof(struct tun_struct), name,
+                                   tun_setup);
+                if (!dev)
+                        return -ENOMEM;
+
+                tun = netdev_priv(dev);
+                tun->dev = dev;
+                tun->flags = flags;
+                /* Be promiscuous by default to maintain previous behaviour. */
+                tun->if_flags = IFF_PROMISC;
+                /* Generate random Ethernet address. */
+                *(u16 *)tun->dev_addr = htons(0x00FF);
+                get_random_bytes(tun->dev_addr + sizeof(u16), 4);
+                memset(tun->chr_filter, 0, sizeof tun->chr_filter);
+
+                tun_net_init(dev);
+
+                if (strchr(dev->name, '%')) {
+                        err = dev_alloc_name(dev, dev->name);
+                        if (err < 0)
+                                goto err_free_dev;
+                }
+
+                err = register_netdevice(tun->dev);
+                if (err < 0)
+                        goto err_free_dev;
+        
+                list_add(&tun->list, &tun_dev_list);
+        }
+
+        DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
+
+        if (ifr->ifr_flags & IFF_NO_PI)
+                tun->flags |= TUN_NO_PI;
+
+        if (ifr->ifr_flags & IFF_ONE_QUEUE)
+                tun->flags |= TUN_ONE_QUEUE;
+
+        file->private_data = tun;
+        tun->attached = 1;
+
+        strcpy(ifr->ifr_name, tun->dev->name);
+        return 0;
+
+ err_free_dev:
+        free_netdev(dev);
+ failed:
+        return err;
+}
+
+static int tun_chr_ioctl(struct inode *inode, struct file *file, 
+                         unsigned int cmd, unsigned long arg)
+{
+        struct tun_struct *tun = file->private_data;
+        void __user* argp = (void __user*)arg;
+        struct ifreq ifr;
+
+        if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
+                if (copy_from_user(&ifr, argp, sizeof ifr))
+                        return -EFAULT;
+
+        if (cmd == TUNSETIFF && !tun) {
+                int err;
+
+                ifr.ifr_name[IFNAMSIZ-1] = '\0';
+
+                rtnl_lock();
+                err = tun_set_iff(file, &ifr);
+                rtnl_unlock();
+
+                if (err)
+                        return err;
+
+                if (copy_to_user(argp, &ifr, sizeof(ifr)))
+                        return -EFAULT;
+                return 0;
+        }
+
+        if (!tun)
+                return -EBADFD;
+
+        DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
+
+        switch (cmd) {
+        case TUNSETNOCSUM:
+                /* Disable/Enable checksum */
+                if (arg)
+                        tun->flags |= TUN_NOCHECKSUM;
+                else
+                        tun->flags &= ~TUN_NOCHECKSUM;
+
+                DBG(KERN_INFO "%s: checksum %s\n",
+                    tun->dev->name, arg ? "disabled" : "enabled");
+                break;
+
+        case TUNSETPERSIST:
+                /* Disable/Enable persist mode */
+                if (arg)
+                        tun->flags |= TUN_PERSIST;
+                else
+                        tun->flags &= ~TUN_PERSIST;
+
+                DBG(KERN_INFO "%s: persist %s\n",
+                    tun->dev->name, arg ? "disabled" : "enabled");
+                break;
+
+        case TUNSETOWNER:
+                /* Set owner of the device */
+                tun->owner = (uid_t) arg;
+
+                DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
+                break;
+
+#ifdef TUN_DEBUG
+        case TUNSETDEBUG:
+                tun->debug = arg;
+                break;
+#endif
+
+        case SIOCGIFFLAGS:
+                ifr.ifr_flags = tun->if_flags;
+                if (copy_to_user( argp, &ifr, sizeof ifr))
+                        return -EFAULT;
+                return 0;
+
+        case SIOCSIFFLAGS:
+                /** Set the character device's interface flags. Currently only
+                 * IFF_PROMISC and IFF_ALLMULTI are used. */
+                tun->if_flags = ifr.ifr_flags;
+                DBG(KERN_INFO "%s: interface flags 0x%lx\n",
+                                tun->dev->name, tun->if_flags);
+                return 0;
+
+        case SIOCGIFHWADDR:
+                memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
+                                min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
+                if (copy_to_user( argp, &ifr, sizeof ifr))
+                        return -EFAULT;
+                return 0;
+
+        case SIOCSIFHWADDR:
+                /** Set the character device's hardware address. This is used when
+                 * filtering packets being sent from the network device to the character
+                 * device. */
+                memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
+                                min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
+                DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
+                                tun->dev->name,
+                                tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
+                                tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
+                return 0;
+
+        case SIOCADDMULTI:
+                /** Add the specified group to the character device's multicast filter
+                 * list. */
+                add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
+                DBG(KERN_DEBUG "%s: add multi: %x:%x:%x:%x:%x:%x\n",
+                                tun->dev->name,
+                                (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1],
+                                (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3],
+                                (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]);
+                return 0;
+
+        case SIOCDELMULTI:
+                /** Remove the specified group from the character device's multicast
+                 * filter list. */
+                del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
+                DBG(KERN_DEBUG "%s: del multi: %x:%x:%x:%x:%x:%x\n",
+                                tun->dev->name,
+                                (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1],
+                                (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3],
+                                (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]);
+                return 0;
+
+        default:
+                return -EINVAL;
+        };
+
+        return 0;
+}
+
+static int tun_chr_fasync(int fd, struct file *file, int on)
+{
+        struct tun_struct *tun = file->private_data;
+        int ret;
+
+        if (!tun)
+                return -EBADFD;
+
+        DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
+
+        if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
+                return ret; 
+ 
+        if (on) {
+                ret = f_setown(file, current->pid, 0);
+                if (ret)
+                        return ret;
+                tun->flags |= TUN_FASYNC;
+        } else 
+                tun->flags &= ~TUN_FASYNC;
+
+        return 0;
+}
+
+static int tun_chr_open(struct inode *inode, struct file * file)
+{
+        DBG1(KERN_INFO "tunX: tun_chr_open\n");
+        file->private_data = NULL;
+        return 0;
+}
+
+static int tun_chr_close(struct inode *inode, struct file *file)
+{
+        struct tun_struct *tun = file->private_data;
+
+        if (!tun)
+                return 0;
+
+        DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
+
+        tun_chr_fasync(-1, file, 0);
+
+        rtnl_lock();
+
+        /* Detach from net device */
+        file->private_data = NULL;
+        tun->attached = 0;
+
+        /* Drop read queue */
+        skb_queue_purge(&tun->readq);
+
+        if (!(tun->flags & TUN_PERSIST)) {
+                list_del(&tun->list);
+                unregister_netdevice(tun->dev);
+        }
+
+        rtnl_unlock();
+
+        return 0;
+}
+
+static struct file_operations tun_fops = {
+        .owner  = THIS_MODULE,  
+        .llseek = no_llseek,
+        .read   = tun_chr_read,
+        .readv  = tun_chr_readv,
+        .write  = tun_chr_write,
+        .writev = tun_chr_writev,
+        .poll   = tun_chr_poll,
+        .ioctl  = tun_chr_ioctl,
+        .open   = tun_chr_open,
+        .release = tun_chr_close,
+        .fasync = tun_chr_fasync                
+};
+
+static struct miscdevice tun_miscdev = {
+        .minor = TUN_MINOR,
+        .name = "tun",
+        .fops = &tun_fops,
+        .devfs_name = "net/tun",
+};
+
+/* ethtool interface */
+
+static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+        cmd->supported          = 0;
+        cmd->advertising        = 0;
+        cmd->speed              = SPEED_10;
+        cmd->duplex             = DUPLEX_FULL;
+        cmd->port               = PORT_TP;
+        cmd->phy_address        = 0;
+        cmd->transceiver        = XCVR_INTERNAL;
+        cmd->autoneg            = AUTONEG_DISABLE;
+        cmd->maxtxpkt           = 0;
+        cmd->maxrxpkt           = 0;
+        return 0;
+}
+
+static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+
+        strcpy(info->driver, DRV_NAME);
+        strcpy(info->version, DRV_VERSION);
+        strcpy(info->fw_version, "N/A");
+
+        switch (tun->flags & TUN_TYPE_MASK) {
+        case TUN_TUN_DEV:
+                strcpy(info->bus_info, "tun");
+                break;
+        case TUN_TAP_DEV:
+                strcpy(info->bus_info, "tap");
+                break;
+        }
+}
+
+static u32 tun_get_msglevel(struct net_device *dev)
+{
+#ifdef TUN_DEBUG
+        struct tun_struct *tun = netdev_priv(dev);
+        return tun->debug;
+#else
+        return -EOPNOTSUPP;
+#endif
+}
+
+static void tun_set_msglevel(struct net_device *dev, u32 value)
+{
+#ifdef TUN_DEBUG
+        struct tun_struct *tun = netdev_priv(dev);
+        tun->debug = value;
+#endif
+}
+
+static u32 tun_get_link(struct net_device *dev)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+        return tun->attached;
+}
+
+static u32 tun_get_rx_csum(struct net_device *dev)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+        return (tun->flags & TUN_NOCHECKSUM) == 0;
+}
+
+static int tun_set_rx_csum(struct net_device *dev, u32 data)
+{
+        struct tun_struct *tun = netdev_priv(dev);
+        if (data)
+                tun->flags &= ~TUN_NOCHECKSUM;
+        else
+                tun->flags |= TUN_NOCHECKSUM;
+        return 0;
+}
+
+static struct ethtool_ops tun_ethtool_ops = {
+        .get_settings   = tun_get_settings,
+        .get_drvinfo    = tun_get_drvinfo,
+        .get_msglevel   = tun_get_msglevel,
+        .set_msglevel   = tun_set_msglevel,
+        .get_link       = tun_get_link,
+        .get_rx_csum    = tun_get_rx_csum,
+        .set_rx_csum    = tun_set_rx_csum
+};
+
+static int __init tun_init(void)
+{
+        int ret = 0;
+
+        printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
+        printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
+
+        ret = misc_register(&tun_miscdev);
+        if (ret)
+                printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
+        return ret;
+}
+
+static void tun_cleanup(void)
+{
+        struct tun_struct *tun, *nxt;
+
+        misc_deregister(&tun_miscdev);  
+
+        rtnl_lock();
+        list_for_each_entry_safe(tun, nxt, &tun_dev_list, list) {
+                DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
+                unregister_netdevice(tun->dev);
+        }
+        rtnl_unlock();
+        
+}
+
+module_init(tun_init);
+module_exit(tun_cleanup);
+MODULE_DESCRIPTION(DRV_DESCRIPTION);
+MODULE_AUTHOR(DRV_COPYRIGHT);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(TUN_MINOR);