summaryrefslogtreecommitdiff
path: root/drivers/net/tun.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r--drivers/net/tun.c883
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);