linux/drivers/net/tun.c
Pavel Emelyanov fc54c65853 [TUN]: Allow to register tun devices in namespace.
This is basically means that a net is set for a new device, but
actually also involves two more steps:

1. mark the tun device as "local", i.e. do not allow for it to
   move across namespaces.

This is done so, since tun device is most often associated to some
file (and thus to some process) and moving the device alone is not
valid while keeping the file and the process outside. The need in 
ability to move a detached persistent device is to be investigated 
later.

2. get the tun device's net when tun becomes attached and put one
   when it becomes detached.

This is needed to handle the case when a task owning the tun dies,
but a files lives for some more time - in this case we must not
allow for net to be freed, since its exit hook will spoil that file's
private data by unregistering the tun from under tun_chr_close.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-16 00:41:53 -07:00

1001 lines
23 KiB
C

/*
* 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:
*
* Brian Braunstein <linuxkernel@bristyle.com> 2007/03/23
* Fixed hw address handling. Now net_device.dev_addr is kept consistent
* with tun.dev_addr when the address is set by this module.
*
* Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
* Add TUNSETLINK ioctl to set the link encapsulation
*
* 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/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 <linux/nsproxy.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <asm/system.h>
#include <asm/uaccess.h>
/* Uncomment to enable debugging */
/* #define TUN_DEBUG 1 */
#ifdef TUN_DEBUG
static int debug;
#define DBG if(tun->debug)printk
#define DBG1 if(debug==2)printk
#else
#define DBG( a... )
#define DBG1( a... )
#endif
struct tun_struct {
struct list_head list;
unsigned long flags;
int attached;
uid_t owner;
gid_t group;
wait_queue_head_t read_wait;
struct sk_buff_head readq;
struct net_device *dev;
struct fasync_struct *fasync;
unsigned long if_flags;
u8 dev_addr[ETH_ALEN];
u32 chr_filter[2];
u32 net_filter[2];
#ifdef TUN_DEBUG
int debug;
#endif
};
/* Network device part of the driver */
static unsigned int tun_net_id;
struct tun_net {
struct list_head dev_list;
};
static const 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. */
dev->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:
dev->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;
DECLARE_MAC_BUF(mac);
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: %s\n",
dev->name, print_mac(mac, mclist->dmi_addr));
}
}
#define MIN_MTU 68
#define MAX_MTU 65535
static int
tun_net_change_mtu(struct net_device *dev, int new_mtu)
{
if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
return -EINVAL;
dev->mtu = new_mtu;
return 0;
}
/* 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;
dev->change_mtu = tun_net_change_mtu;
/* 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);
dev->change_mtu = tun_net_change_mtu;
/* random address already created for us by tun_set_iff, use it */
memcpy(dev->dev_addr, tun->dev_addr, min(sizeof(tun->dev_addr), sizeof(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_empty(&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 (unlikely(len < ETH_HLEN))
return -EINVAL;
}
if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
tun->dev->stats.rx_dropped++;
return -ENOMEM;
}
if (align)
skb_reserve(skb, align);
if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
tun->dev->stats.rx_dropped++;
kfree_skb(skb);
return -EFAULT;
}
switch (tun->flags & TUN_TYPE_MASK) {
case TUN_TUN_DEV:
skb_reset_mac_header(skb);
skb->protocol = pi.proto;
skb->dev = tun->dev;
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->dev->stats.rx_packets++;
tun->dev->stats.rx_bytes += len;
return count;
}
static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
unsigned long count, loff_t pos)
{
struct tun_struct *tun = iocb->ki_filp->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_length(iv, count));
}
/* 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->dev->stats.tx_packets++;
tun->dev->stats.tx_bytes += len;
return total;
}
static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
unsigned long count, loff_t pos)
{
struct file *file = iocb->ki_filp;
struct tun_struct *tun = file->private_data;
DECLARE_WAITQUEUE(wait, current);
struct sk_buff *skb;
ssize_t len, ret = 0;
DECLARE_MAC_BUF(mac);
if (!tun)
return -EBADFD;
DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
len = iov_length(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.
*/
skb_copy_from_linear_data(skb, addr, 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: %s\n",
tun->dev->name, print_mac(mac, addr));
ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
kfree_skb(skb);
break;
} else {
DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %s\n",
tun->dev->name, print_mac(mac, addr));
kfree_skb(skb);
continue;
}
}
current->state = TASK_RUNNING;
remove_wait_queue(&tun->read_wait, &wait);
return ret;
}
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;
tun->group = -1;
dev->open = tun_net_open;
dev->hard_start_xmit = tun_net_xmit;
dev->stop = tun_net_close;
dev->ethtool_ops = &tun_ethtool_ops;
dev->destructor = free_netdev;
dev->features |= NETIF_F_NETNS_LOCAL;
}
static struct tun_struct *tun_get_by_name(struct tun_net *tn, const char *name)
{
struct tun_struct *tun;
ASSERT_RTNL();
list_for_each_entry(tun, &tn->dev_list, list) {
if (!strncmp(tun->dev->name, name, IFNAMSIZ))
return tun;
}
return NULL;
}
static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
{
struct tun_net *tn;
struct tun_struct *tun;
struct net_device *dev;
int err;
tn = net_generic(net, tun_net_id);
tun = tun_get_by_name(tn, ifr->ifr_name);
if (tun) {
if (tun->attached)
return -EBUSY;
/* Check permissions */
if (((tun->owner != -1 &&
current->euid != tun->owner) ||
(tun->group != -1 &&
current->egid != tun->group)) &&
!capable(CAP_NET_ADMIN))
return -EPERM;
}
else if (__dev_get_by_name(net, ifr->ifr_name))
return -EINVAL;
else {
char *name;
unsigned long flags = 0;
err = -EINVAL;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
/* 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;
dev_net_set(dev, net);
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. */
*(__be16 *)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, &tn->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;
else
tun->flags &= ~TUN_NO_PI;
if (ifr->ifr_flags & IFF_ONE_QUEUE)
tun->flags |= TUN_ONE_QUEUE;
else
tun->flags &= ~TUN_ONE_QUEUE;
file->private_data = tun;
tun->attached = 1;
get_net(dev_net(tun->dev));
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;
DECLARE_MAC_BUF(mac);
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(current->nsproxy->net_ns, 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 ? "enabled" : "disabled");
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;
case TUNSETGROUP:
/* Set group of the device */
tun->group= (gid_t) arg;
DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
break;
case TUNSETLINK:
/* Only allow setting the type when the interface is down */
if (tun->dev->flags & IFF_UP) {
DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
tun->dev->name);
return -EBUSY;
} else {
tun->dev->type = (int) arg;
DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
}
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:
/* Note: the actual net device's address may be different */
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:
{
/* try to set the actual net device's hw address */
int ret;
rtnl_lock();
ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
rtnl_unlock();
if (ret == 0) {
/** 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 ret;
}
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: %s\n",
tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
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: %s\n",
tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
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, task_pid(current), PIDTYPE_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;
put_net(dev_net(tun->dev));
/* 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 const struct file_operations tun_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = do_sync_read,
.aio_read = tun_chr_aio_read,
.write = do_sync_write,
.aio_write = tun_chr_aio_write,
.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,
};
/* 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 const 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 tun_init_net(struct net *net)
{
struct tun_net *tn;
tn = kmalloc(sizeof(*tn), GFP_KERNEL);
if (tn == NULL)
return -ENOMEM;
INIT_LIST_HEAD(&tn->dev_list);
if (net_assign_generic(net, tun_net_id, tn)) {
kfree(tn);
return -ENOMEM;
}
return 0;
}
static void tun_exit_net(struct net *net)
{
struct tun_net *tn;
struct tun_struct *tun, *nxt;
tn = net_generic(net, tun_net_id);
rtnl_lock();
list_for_each_entry_safe(tun, nxt, &tn->dev_list, list) {
DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
unregister_netdevice(tun->dev);
}
rtnl_unlock();
kfree(tn);
}
static struct pernet_operations tun_net_ops = {
.init = tun_init_net,
.exit = tun_exit_net,
};
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 = register_pernet_gen_device(&tun_net_id, &tun_net_ops);
if (ret) {
printk(KERN_ERR "tun: Can't register pernet ops\n");
goto err_pernet;
}
ret = misc_register(&tun_miscdev);
if (ret) {
printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
goto err_misc;
}
return 0;
err_misc:
unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
err_pernet:
return ret;
}
static void tun_cleanup(void)
{
misc_deregister(&tun_miscdev);
unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
}
module_init(tun_init);
module_exit(tun_cleanup);
MODULE_DESCRIPTION(DRV_DESCRIPTION);
MODULE_AUTHOR(DRV_COPYRIGHT);
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(TUN_MINOR);