diff options
author | Ralf Baechle <ralf@linux-mips.org> | 2000-08-28 22:00:09 +0000 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2000-08-28 22:00:09 +0000 |
commit | 1a1d77dd589de5a567fa95e36aa6999c704ceca4 (patch) | |
tree | 141e31f89f18b9fe0831f31852e0435ceaccafc5 /drivers/net/tun.c | |
parent | fb9c690a18b3d66925a65b17441c37fa14d4370b (diff) |
Merge with 2.4.0-test7.
Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r-- | drivers/net/tun.c | 535 |
1 files changed, 535 insertions, 0 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c new file mode 100644 index 000000000..26282e38f --- /dev/null +++ b/drivers/net/tun.c @@ -0,0 +1,535 @@ +/* + * TUN - Universal TUN/TAP device driver. + * Copyright (C) 1999-2000 Maxim Krasnyansky <max_mk@yahoo.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 1.1 2000/08/23 05:59:28 davem Exp $ + */ + +/* + * Daniel Podlejski <underley@underley.eu.org> + * Modifications for 2.3.99-pre5 kernel. + */ + +#define TUN_VER "1.1" + +#include <linux/module.h> + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/major.h> +#include <linux/sched.h> +#include <linux/malloc.h> +#include <linux/poll.h> +#include <linux/fcntl.h> +#include <linux/init.h> +#include <linux/devfs_fs_kernel.h> +#include <linux/random.h> + +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/skbuff.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 <asm/system.h> +#include <asm/uaccess.h> + + +#ifdef TUN_DEBUG +static int debug=0; +#endif + +/* Network device part of the driver */ + +/* Net device open. */ +static int tun_net_open(struct net_device *dev) +{ +#ifdef TUN_DEBUG + struct tun_struct *tun = (struct tun_struct *)dev->priv; + + DBG(KERN_INFO "%s: tun_net_open\n", tun->name); +#endif + + netif_start_queue(dev); + + return 0; +} + +/* Net device close. */ +static int tun_net_close(struct net_device *dev) +{ +#ifdef TUN_DEBUG + struct tun_struct *tun = (struct tun_struct *)dev->priv; + + DBG(KERN_INFO "%s: tun_net_close\n", tun->name); +#endif + + 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 = (struct tun_struct *)dev->priv; + + DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->name, skb->len); + + + if (netif_queue_stopped(dev)) + return 1; + + tun->stats.tx_packets++; + + /* Queue frame */ + skb_queue_tail(&tun->txq, skb); + if (skb_queue_len(&tun->txq) >= TUN_TXQ_SIZE) + netif_stop_queue(dev); + + if (tun->flags & TUN_FASYNC) + kill_fasync(&tun->fasync, SIGIO, POLL_IN); + + /* Wake up process */ + wake_up_interruptible(&tun->read_wait); + + return 0; +} + +static void tun_net_mclist(struct net_device *dev) +{ +#ifdef TUN_DEBUG + struct tun_struct *tun = (struct tun_struct *)dev->priv; + + DBG(KERN_INFO "%s: tun_net_mclist\n", tun->name); +#endif + + /* Nothing to do for multicast filters. + * We always accept all frames. + */ + return; +} + +static struct net_device_stats *tun_net_stats(struct net_device *dev) +{ + struct tun_struct *tun = (struct tun_struct *)dev->priv; + + return &tun->stats; +} + +/* Initialize net device. */ +int tun_net_init(struct net_device *dev) +{ + struct tun_struct *tun = (struct tun_struct *)dev->priv; + + DBG(KERN_INFO "%s: tun_net_init\n", tun->name); + + dev->open = tun_net_open; + dev->hard_start_xmit = tun_net_xmit; + dev->stop = tun_net_close; + dev->get_stats = tun_net_stats; + + 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; + + /* Type PPP seems most suitable */ + dev->type = ARPHRD_PPP; + dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; + dev->tx_queue_len = 10; + + dev_init_buffers(dev); + break; + + case TUN_TAP_DEV: + /* Ethernet TAP Device */ + dev->set_multicast_list = tun_net_mclist; + + /* Generate random Ethernet address. */ + *(u16 *)dev->dev_addr = htons(0x00FF); + get_random_bytes(dev->dev_addr + sizeof(u16), 4); + + ether_setup(dev); + break; + }; + + return 0; +} + +/* Character device part */ + +/* Poll */ +static unsigned int tun_chr_poll(struct file *file, poll_table * wait) +{ + struct tun_struct *tun = (struct tun_struct *)file->private_data; + + DBG(KERN_INFO "%s: tun_chr_poll\n", tun->name); + + poll_wait(file, &tun->read_wait, wait); + + if (skb_queue_len(&tun->txq)) + return POLLIN | POLLRDNORM; + + return POLLOUT | POLLWRNORM; +} + +/* Get packet from user space buffer(already verified) */ +static __inline__ ssize_t tun_get_user(struct tun_struct *tun, const char *buf, size_t count) +{ + struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) }; + register const char *ptr = buf; + register int len = count; + struct sk_buff *skb; + + if (len > TUN_MAX_FRAME) + return -EINVAL; + + if (!(tun->flags & TUN_NO_PI)) { + if ((len -= sizeof(pi)) < 0) + return -EINVAL; + + copy_from_user(&pi, ptr, sizeof(pi)); + ptr += sizeof(pi); + } + + if (!(skb = alloc_skb(len + 2, GFP_KERNEL))) { + tun->stats.rx_dropped++; + return -ENOMEM; + } + + skb_reserve(skb, 2); + copy_from_user(skb_put(skb, count), ptr, len); + + 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(skb); + + tun->stats.rx_packets++; + return count; +} + +/* Write */ +static ssize_t tun_chr_write(struct file * file, const char * buf, + size_t count, loff_t *pos) +{ + struct tun_struct *tun = (struct tun_struct *)file->private_data; + + DBG(KERN_INFO "%s: tun_chr_write %d\n", tun->name, count); + + if (!(tun->flags & TUN_IFF_SET)) + return -EBUSY; + + if (verify_area(VERIFY_READ, buf, count)) + return -EFAULT; + + return tun_get_user(tun, buf, count); +} + +/* Put packet to user space buffer(already verified) */ +static __inline__ ssize_t tun_put_user(struct tun_struct *tun, + struct sk_buff *skb, + char *buf, int count) +{ + struct tun_pi pi = { 0, skb->protocol }; + int len = count, total = 0; + char *ptr = buf; + + 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; + } + + copy_to_user(ptr, &pi, sizeof(pi)); + + total += sizeof(pi); + ptr += sizeof(pi); + } + + len = MIN(skb->len, len); + copy_to_user(ptr, skb->data, len); + total += len; + + return total; +} + +/* Read */ +static ssize_t tun_chr_read(struct file * file, char * buf, + size_t count, loff_t *pos) +{ + struct tun_struct *tun = (struct tun_struct *)file->private_data; + DECLARE_WAITQUEUE(wait, current); + struct sk_buff *skb; + ssize_t ret = 0; + + DBG(KERN_INFO "%s: tun_chr_read\n", tun->name); + + add_wait_queue(&tun->read_wait, &wait); + while (count) { + current->state = TASK_INTERRUPTIBLE; + + /* Read frames from device queue */ + if (!(skb=skb_dequeue(&tun->txq))) { + 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_start_queue(&tun->dev); + + if (!verify_area(VERIFY_WRITE, buf, count)) + ret = tun_put_user(tun, skb, buf, count); + else + ret = -EFAULT; + + kfree_skb(skb); + break; + } + + current->state = TASK_RUNNING; + remove_wait_queue(&tun->read_wait, &wait); + + return ret; +} + +static loff_t tun_chr_lseek(struct file * file, loff_t offset, int origin) +{ + return -ESPIPE; +} + +static int tun_set_iff(struct tun_struct *tun, unsigned long arg) +{ + struct ifreq ifr; + char *mask; + + if (copy_from_user(&ifr, (void *)arg, sizeof(ifr))) + return -EFAULT; + ifr.ifr_name[IFNAMSIZ-1] = '\0'; + + if (tun->flags & TUN_IFF_SET) + return -EEXIST; + + /* Set dev type */ + if (ifr.ifr_flags & IFF_TUN) { + /* TUN device */ + tun->flags |= TUN_TUN_DEV; + mask = "tun%d"; + } else if (ifr.ifr_flags & IFF_TAP) { + /* TAP device */ + tun->flags |= TUN_TAP_DEV; + mask = "tap%d"; + } else + return -EINVAL; + + if (ifr.ifr_flags & IFF_NO_PI) + tun->flags |= TUN_NO_PI; + + if (*ifr.ifr_name) + strcpy(tun->dev.name, ifr.ifr_name); + else + strcpy(tun->dev.name, mask); + + /* Register net device */ + if (register_netdev(&tun->dev)) + return -EBUSY; + + tun->flags |= TUN_IFF_SET; + strcpy(tun->name, tun->dev.name); + + /* Return iface info to the user space */ + strcpy(ifr.ifr_name, tun->dev.name); + copy_to_user((void *)arg, &ifr, sizeof(ifr)); + + return 0; +} + +static int tun_chr_ioctl(struct inode *inode, struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct tun_struct *tun = (struct tun_struct *)file->private_data; + + DBG(KERN_INFO "%s: tun_chr_ioctl\n", tun->name); + + switch (cmd) { + case TUNSETIFF: + return tun_set_iff(tun, arg); + + case TUNSETNOCSUM: + /* Disable/Enable checksum on net iface */ + if (arg) + tun->flags |= TUN_NOCHECKSUM; + else + tun->flags &= ~TUN_NOCHECKSUM; + + DBG(KERN_INFO "%s: checksum %s\n", + tun->name, arg ? "disabled" : "enabled"); + break; + +#ifdef TUN_DEBUG + case TUNSETDEBUG: + tun->debug = arg; + break; +#endif + + default: + return -EINVAL; + }; + + return 0; +} + +static int tun_chr_fasync(int fd, struct file *file, int on) +{ + struct tun_struct *tun = (struct tun_struct *)file->private_data; + int ret; + + DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->name, on); + + if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0) + return ret; + + if (on) + tun->flags |= TUN_FASYNC; + else + tun->flags &= ~TUN_FASYNC; + + return 0; +} + +static int tun_chr_open(struct inode *inode, struct file * file) +{ + struct tun_struct *tun = NULL; + + DBG1(KERN_INFO "tunX: tun_chr_open\n"); + + tun = kmalloc(sizeof(struct tun_struct), GFP_KERNEL); + if (tun == NULL) + return -ENOMEM; + + memset(tun, 0, sizeof(struct tun_struct)); + file->private_data = tun; + + skb_queue_head_init(&tun->txq); + init_waitqueue_head(&tun->read_wait); + + sprintf(tun->name, "tunX"); + + tun->dev.init = tun_net_init; + tun->dev.priv = tun; + + MOD_INC_USE_COUNT; + + return 0; +} + +static int tun_chr_close(struct inode *inode, struct file *file) +{ + struct tun_struct *tun = (struct tun_struct *)file->private_data; + + DBG(KERN_INFO "%s: tun_chr_close\n", tun->name); + + if (tun->flags & TUN_IFF_SET) { + rtnl_lock(); + dev_close(&tun->dev); + rtnl_unlock(); + + /* Drop TX queue */ + skb_queue_purge(&tun->txq); + + unregister_netdev(&tun->dev); + } + + kfree(tun); + file->private_data = NULL; + + MOD_DEC_USE_COUNT; + return 0; +} + +static struct file_operations tun_fops = { + owner: THIS_MODULE, + llseek: tun_chr_lseek, + read: tun_chr_read, + write: tun_chr_write, + poll: tun_chr_poll, + ioctl: tun_chr_ioctl, + open: tun_chr_open, + release:tun_chr_close, + fasync: tun_chr_fasync +}; + +static devfs_handle_t devfs_handle = NULL; + +int __init tun_init(void) +{ + printk(KERN_INFO "Universal TUN/TAP device driver %s " + "(C)1999-2000 Maxim Krasnyansky\n", TUN_VER); + + if (devfs_register_chrdev(TUN_MAJOR, "tun", &tun_fops)) { + printk(KERN_ERR "tun: Can't register char device %d\n", + TUN_MAJOR); + return -EIO; + } + + devfs_handle = devfs_register(NULL, "net/tun", DEVFS_FL_DEFAULT, + TUN_MAJOR, 0, + S_IFCHR | S_IRUSR | S_IWUSR, + &tun_fops, NULL); + +#ifdef MODULE + return 0; +#else + /* If driver is not module, tun_init will be called from Space.c. + * Return non-zero not to register fake device. + */ + return 1; +#endif +} + +void tun_cleanup(void) +{ + devfs_unregister_chrdev(TUN_MAJOR,"tun"); + devfs_unregister(devfs_handle); +} + +module_init(tun_init); +module_exit(tun_cleanup); |