Pull bugzilla-9429 into release branch
[pv_ops_mirror.git] / drivers / net / tun.c
blob1f76446959765ef577382517e7039c0ab044d5c3
1 /*
2 * TUN - Universal TUN/TAP device driver.
3 * Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
19 * Changes:
21 * Brian Braunstein <linuxkernel@bristyle.com> 2007/03/23
22 * Fixed hw address handling. Now net_device.dev_addr is kept consistent
23 * with tun.dev_addr when the address is set by this module.
25 * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
26 * Add TUNSETLINK ioctl to set the link encapsulation
28 * Mark Smith <markzzzsmith@yahoo.com.au>
29 * Use random_ether_addr() for tap MAC address.
31 * Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20
32 * Fixes in packet dropping, queue length setting and queue wakeup.
33 * Increased default tx queue length.
34 * Added ethtool API.
35 * Minor cleanups
37 * Daniel Podlejski <underley@underley.eu.org>
38 * Modifications for 2.3.99-pre5 kernel.
41 #define DRV_NAME "tun"
42 #define DRV_VERSION "1.6"
43 #define DRV_DESCRIPTION "Universal TUN/TAP device driver"
44 #define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/kernel.h>
49 #include <linux/major.h>
50 #include <linux/slab.h>
51 #include <linux/poll.h>
52 #include <linux/fcntl.h>
53 #include <linux/init.h>
54 #include <linux/skbuff.h>
55 #include <linux/netdevice.h>
56 #include <linux/etherdevice.h>
57 #include <linux/miscdevice.h>
58 #include <linux/ethtool.h>
59 #include <linux/rtnetlink.h>
60 #include <linux/if.h>
61 #include <linux/if_arp.h>
62 #include <linux/if_ether.h>
63 #include <linux/if_tun.h>
64 #include <linux/crc32.h>
65 #include <net/net_namespace.h>
67 #include <asm/system.h>
68 #include <asm/uaccess.h>
70 #ifdef TUN_DEBUG
71 static int debug;
72 #endif
74 /* Network device part of the driver */
76 static LIST_HEAD(tun_dev_list);
77 static const struct ethtool_ops tun_ethtool_ops;
79 /* Net device open. */
80 static int tun_net_open(struct net_device *dev)
82 netif_start_queue(dev);
83 return 0;
86 /* Net device close. */
87 static int tun_net_close(struct net_device *dev)
89 netif_stop_queue(dev);
90 return 0;
93 /* Net device start xmit */
94 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
96 struct tun_struct *tun = netdev_priv(dev);
98 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
100 /* Drop packet if interface is not attached */
101 if (!tun->attached)
102 goto drop;
104 /* Packet dropping */
105 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
106 if (!(tun->flags & TUN_ONE_QUEUE)) {
107 /* Normal queueing mode. */
108 /* Packet scheduler handles dropping of further packets. */
109 netif_stop_queue(dev);
111 /* We won't see all dropped packets individually, so overrun
112 * error is more appropriate. */
113 dev->stats.tx_fifo_errors++;
114 } else {
115 /* Single queue mode.
116 * Driver handles dropping of all packets itself. */
117 goto drop;
121 /* Queue packet */
122 skb_queue_tail(&tun->readq, skb);
123 dev->trans_start = jiffies;
125 /* Notify and wake up reader process */
126 if (tun->flags & TUN_FASYNC)
127 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
128 wake_up_interruptible(&tun->read_wait);
129 return 0;
131 drop:
132 dev->stats.tx_dropped++;
133 kfree_skb(skb);
134 return 0;
137 /** Add the specified Ethernet address to this multicast filter. */
138 static void
139 add_multi(u32* filter, const u8* addr)
141 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
142 filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
145 /** Remove the specified Ethernet addres from this multicast filter. */
146 static void
147 del_multi(u32* filter, const u8* addr)
149 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
150 filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31));
153 /** Update the list of multicast groups to which the network device belongs.
154 * This list is used to filter packets being sent from the character device to
155 * the network device. */
156 static void
157 tun_net_mclist(struct net_device *dev)
159 struct tun_struct *tun = netdev_priv(dev);
160 const struct dev_mc_list *mclist;
161 int i;
162 DECLARE_MAC_BUF(mac);
163 DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n",
164 dev->name, dev->mc_count);
165 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
166 for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL;
167 i++, mclist = mclist->next) {
168 add_multi(tun->net_filter, mclist->dmi_addr);
169 DBG(KERN_DEBUG "%s: tun_net_mclist: %s\n",
170 dev->name, print_mac(mac, mclist->dmi_addr));
174 #define MIN_MTU 68
175 #define MAX_MTU 65535
177 static int
178 tun_net_change_mtu(struct net_device *dev, int new_mtu)
180 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
181 return -EINVAL;
182 dev->mtu = new_mtu;
183 return 0;
186 /* Initialize net device. */
187 static void tun_net_init(struct net_device *dev)
189 struct tun_struct *tun = netdev_priv(dev);
191 switch (tun->flags & TUN_TYPE_MASK) {
192 case TUN_TUN_DEV:
193 /* Point-to-Point TUN Device */
194 dev->hard_header_len = 0;
195 dev->addr_len = 0;
196 dev->mtu = 1500;
197 dev->change_mtu = tun_net_change_mtu;
199 /* Zero header length */
200 dev->type = ARPHRD_NONE;
201 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
202 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
203 break;
205 case TUN_TAP_DEV:
206 /* Ethernet TAP Device */
207 dev->set_multicast_list = tun_net_mclist;
209 ether_setup(dev);
210 dev->change_mtu = tun_net_change_mtu;
212 /* random address already created for us by tun_set_iff, use it */
213 memcpy(dev->dev_addr, tun->dev_addr, min(sizeof(tun->dev_addr), sizeof(dev->dev_addr)) );
215 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
216 break;
220 /* Character device part */
222 /* Poll */
223 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
225 struct tun_struct *tun = file->private_data;
226 unsigned int mask = POLLOUT | POLLWRNORM;
228 if (!tun)
229 return -EBADFD;
231 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
233 poll_wait(file, &tun->read_wait, wait);
235 if (!skb_queue_empty(&tun->readq))
236 mask |= POLLIN | POLLRDNORM;
238 return mask;
241 /* Get packet from user space buffer */
242 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
244 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
245 struct sk_buff *skb;
246 size_t len = count, align = 0;
248 if (!(tun->flags & TUN_NO_PI)) {
249 if ((len -= sizeof(pi)) > count)
250 return -EINVAL;
252 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
253 return -EFAULT;
256 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV)
257 align = NET_IP_ALIGN;
259 if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
260 tun->dev->stats.rx_dropped++;
261 return -ENOMEM;
264 if (align)
265 skb_reserve(skb, align);
266 if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
267 tun->dev->stats.rx_dropped++;
268 kfree_skb(skb);
269 return -EFAULT;
272 switch (tun->flags & TUN_TYPE_MASK) {
273 case TUN_TUN_DEV:
274 skb_reset_mac_header(skb);
275 skb->protocol = pi.proto;
276 skb->dev = tun->dev;
277 break;
278 case TUN_TAP_DEV:
279 skb->protocol = eth_type_trans(skb, tun->dev);
280 break;
283 if (tun->flags & TUN_NOCHECKSUM)
284 skb->ip_summed = CHECKSUM_UNNECESSARY;
286 netif_rx_ni(skb);
287 tun->dev->last_rx = jiffies;
289 tun->dev->stats.rx_packets++;
290 tun->dev->stats.rx_bytes += len;
292 return count;
295 static inline size_t iov_total(const struct iovec *iv, unsigned long count)
297 unsigned long i;
298 size_t len;
300 for (i = 0, len = 0; i < count; i++)
301 len += iv[i].iov_len;
303 return len;
306 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
307 unsigned long count, loff_t pos)
309 struct tun_struct *tun = iocb->ki_filp->private_data;
311 if (!tun)
312 return -EBADFD;
314 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
316 return tun_get_user(tun, (struct iovec *) iv, iov_total(iv, count));
319 /* Put packet to the user space buffer */
320 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
321 struct sk_buff *skb,
322 struct iovec *iv, int len)
324 struct tun_pi pi = { 0, skb->protocol };
325 ssize_t total = 0;
327 if (!(tun->flags & TUN_NO_PI)) {
328 if ((len -= sizeof(pi)) < 0)
329 return -EINVAL;
331 if (len < skb->len) {
332 /* Packet will be striped */
333 pi.flags |= TUN_PKT_STRIP;
336 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
337 return -EFAULT;
338 total += sizeof(pi);
341 len = min_t(int, skb->len, len);
343 skb_copy_datagram_iovec(skb, 0, iv, len);
344 total += len;
346 tun->dev->stats.tx_packets++;
347 tun->dev->stats.tx_bytes += len;
349 return total;
352 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
353 unsigned long count, loff_t pos)
355 struct file *file = iocb->ki_filp;
356 struct tun_struct *tun = file->private_data;
357 DECLARE_WAITQUEUE(wait, current);
358 struct sk_buff *skb;
359 ssize_t len, ret = 0;
360 DECLARE_MAC_BUF(mac);
362 if (!tun)
363 return -EBADFD;
365 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
367 len = iov_total(iv, count);
368 if (len < 0)
369 return -EINVAL;
371 add_wait_queue(&tun->read_wait, &wait);
372 while (len) {
373 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
374 u8 addr[ ETH_ALEN];
375 int bit_nr;
377 current->state = TASK_INTERRUPTIBLE;
379 /* Read frames from the queue */
380 if (!(skb=skb_dequeue(&tun->readq))) {
381 if (file->f_flags & O_NONBLOCK) {
382 ret = -EAGAIN;
383 break;
385 if (signal_pending(current)) {
386 ret = -ERESTARTSYS;
387 break;
390 /* Nothing to read, let's sleep */
391 schedule();
392 continue;
394 netif_wake_queue(tun->dev);
396 /** Decide whether to accept this packet. This code is designed to
397 * behave identically to an Ethernet interface. Accept the packet if
398 * - we are promiscuous.
399 * - the packet is addressed to us.
400 * - the packet is broadcast.
401 * - the packet is multicast and
402 * - we are multicast promiscous.
403 * - we belong to the multicast group.
405 skb_copy_from_linear_data(skb, addr, min_t(size_t, sizeof addr,
406 skb->len));
407 bit_nr = ether_crc(sizeof addr, addr) >> 26;
408 if ((tun->if_flags & IFF_PROMISC) ||
409 memcmp(addr, tun->dev_addr, sizeof addr) == 0 ||
410 memcmp(addr, ones, sizeof addr) == 0 ||
411 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) ||
412 (addr[0] == 0x33 && addr[1] == 0x33)) &&
413 ((tun->if_flags & IFF_ALLMULTI) ||
414 (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) {
415 DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %s\n",
416 tun->dev->name, print_mac(mac, addr));
417 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
418 kfree_skb(skb);
419 break;
420 } else {
421 DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %s\n",
422 tun->dev->name, print_mac(mac, addr));
423 kfree_skb(skb);
424 continue;
428 current->state = TASK_RUNNING;
429 remove_wait_queue(&tun->read_wait, &wait);
431 return ret;
434 static void tun_setup(struct net_device *dev)
436 struct tun_struct *tun = netdev_priv(dev);
438 skb_queue_head_init(&tun->readq);
439 init_waitqueue_head(&tun->read_wait);
441 tun->owner = -1;
442 tun->group = -1;
444 dev->open = tun_net_open;
445 dev->hard_start_xmit = tun_net_xmit;
446 dev->stop = tun_net_close;
447 dev->ethtool_ops = &tun_ethtool_ops;
448 dev->destructor = free_netdev;
451 static struct tun_struct *tun_get_by_name(const char *name)
453 struct tun_struct *tun;
455 ASSERT_RTNL();
456 list_for_each_entry(tun, &tun_dev_list, list) {
457 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
458 return tun;
461 return NULL;
464 static int tun_set_iff(struct file *file, struct ifreq *ifr)
466 struct tun_struct *tun;
467 struct net_device *dev;
468 int err;
470 tun = tun_get_by_name(ifr->ifr_name);
471 if (tun) {
472 if (tun->attached)
473 return -EBUSY;
475 /* Check permissions */
476 if (((tun->owner != -1 &&
477 current->euid != tun->owner) ||
478 (tun->group != -1 &&
479 current->egid != tun->group)) &&
480 !capable(CAP_NET_ADMIN))
481 return -EPERM;
483 else if (__dev_get_by_name(&init_net, ifr->ifr_name))
484 return -EINVAL;
485 else {
486 char *name;
487 unsigned long flags = 0;
489 err = -EINVAL;
491 if (!capable(CAP_NET_ADMIN))
492 return -EPERM;
494 /* Set dev type */
495 if (ifr->ifr_flags & IFF_TUN) {
496 /* TUN device */
497 flags |= TUN_TUN_DEV;
498 name = "tun%d";
499 } else if (ifr->ifr_flags & IFF_TAP) {
500 /* TAP device */
501 flags |= TUN_TAP_DEV;
502 name = "tap%d";
503 } else
504 goto failed;
506 if (*ifr->ifr_name)
507 name = ifr->ifr_name;
509 dev = alloc_netdev(sizeof(struct tun_struct), name,
510 tun_setup);
511 if (!dev)
512 return -ENOMEM;
514 tun = netdev_priv(dev);
515 tun->dev = dev;
516 tun->flags = flags;
517 /* Be promiscuous by default to maintain previous behaviour. */
518 tun->if_flags = IFF_PROMISC;
519 /* Generate random Ethernet address. */
520 *(u16 *)tun->dev_addr = htons(0x00FF);
521 get_random_bytes(tun->dev_addr + sizeof(u16), 4);
522 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
524 tun_net_init(dev);
526 if (strchr(dev->name, '%')) {
527 err = dev_alloc_name(dev, dev->name);
528 if (err < 0)
529 goto err_free_dev;
532 err = register_netdevice(tun->dev);
533 if (err < 0)
534 goto err_free_dev;
536 list_add(&tun->list, &tun_dev_list);
539 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
541 if (ifr->ifr_flags & IFF_NO_PI)
542 tun->flags |= TUN_NO_PI;
544 if (ifr->ifr_flags & IFF_ONE_QUEUE)
545 tun->flags |= TUN_ONE_QUEUE;
547 file->private_data = tun;
548 tun->attached = 1;
550 strcpy(ifr->ifr_name, tun->dev->name);
551 return 0;
553 err_free_dev:
554 free_netdev(dev);
555 failed:
556 return err;
559 static int tun_chr_ioctl(struct inode *inode, struct file *file,
560 unsigned int cmd, unsigned long arg)
562 struct tun_struct *tun = file->private_data;
563 void __user* argp = (void __user*)arg;
564 struct ifreq ifr;
565 DECLARE_MAC_BUF(mac);
567 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
568 if (copy_from_user(&ifr, argp, sizeof ifr))
569 return -EFAULT;
571 if (cmd == TUNSETIFF && !tun) {
572 int err;
574 ifr.ifr_name[IFNAMSIZ-1] = '\0';
576 rtnl_lock();
577 err = tun_set_iff(file, &ifr);
578 rtnl_unlock();
580 if (err)
581 return err;
583 if (copy_to_user(argp, &ifr, sizeof(ifr)))
584 return -EFAULT;
585 return 0;
588 if (!tun)
589 return -EBADFD;
591 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
593 switch (cmd) {
594 case TUNSETNOCSUM:
595 /* Disable/Enable checksum */
596 if (arg)
597 tun->flags |= TUN_NOCHECKSUM;
598 else
599 tun->flags &= ~TUN_NOCHECKSUM;
601 DBG(KERN_INFO "%s: checksum %s\n",
602 tun->dev->name, arg ? "disabled" : "enabled");
603 break;
605 case TUNSETPERSIST:
606 /* Disable/Enable persist mode */
607 if (arg)
608 tun->flags |= TUN_PERSIST;
609 else
610 tun->flags &= ~TUN_PERSIST;
612 DBG(KERN_INFO "%s: persist %s\n",
613 tun->dev->name, arg ? "disabled" : "enabled");
614 break;
616 case TUNSETOWNER:
617 /* Set owner of the device */
618 tun->owner = (uid_t) arg;
620 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
621 break;
623 case TUNSETGROUP:
624 /* Set group of the device */
625 tun->group= (gid_t) arg;
627 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
628 break;
630 case TUNSETLINK:
631 /* Only allow setting the type when the interface is down */
632 if (tun->dev->flags & IFF_UP) {
633 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
634 tun->dev->name);
635 return -EBUSY;
636 } else {
637 tun->dev->type = (int) arg;
638 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
640 break;
642 #ifdef TUN_DEBUG
643 case TUNSETDEBUG:
644 tun->debug = arg;
645 break;
646 #endif
648 case SIOCGIFFLAGS:
649 ifr.ifr_flags = tun->if_flags;
650 if (copy_to_user( argp, &ifr, sizeof ifr))
651 return -EFAULT;
652 return 0;
654 case SIOCSIFFLAGS:
655 /** Set the character device's interface flags. Currently only
656 * IFF_PROMISC and IFF_ALLMULTI are used. */
657 tun->if_flags = ifr.ifr_flags;
658 DBG(KERN_INFO "%s: interface flags 0x%lx\n",
659 tun->dev->name, tun->if_flags);
660 return 0;
662 case SIOCGIFHWADDR:
663 /* Note: the actual net device's address may be different */
664 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
665 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
666 if (copy_to_user( argp, &ifr, sizeof ifr))
667 return -EFAULT;
668 return 0;
670 case SIOCSIFHWADDR:
672 /* try to set the actual net device's hw address */
673 int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
675 if (ret == 0) {
676 /** Set the character device's hardware address. This is used when
677 * filtering packets being sent from the network device to the character
678 * device. */
679 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
680 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
681 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
682 tun->dev->name,
683 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
684 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
687 return ret;
690 case SIOCADDMULTI:
691 /** Add the specified group to the character device's multicast filter
692 * list. */
693 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
694 DBG(KERN_DEBUG "%s: add multi: %s\n",
695 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
696 return 0;
698 case SIOCDELMULTI:
699 /** Remove the specified group from the character device's multicast
700 * filter list. */
701 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
702 DBG(KERN_DEBUG "%s: del multi: %s\n",
703 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
704 return 0;
706 default:
707 return -EINVAL;
710 return 0;
713 static int tun_chr_fasync(int fd, struct file *file, int on)
715 struct tun_struct *tun = file->private_data;
716 int ret;
718 if (!tun)
719 return -EBADFD;
721 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
723 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
724 return ret;
726 if (on) {
727 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
728 if (ret)
729 return ret;
730 tun->flags |= TUN_FASYNC;
731 } else
732 tun->flags &= ~TUN_FASYNC;
734 return 0;
737 static int tun_chr_open(struct inode *inode, struct file * file)
739 DBG1(KERN_INFO "tunX: tun_chr_open\n");
740 file->private_data = NULL;
741 return 0;
744 static int tun_chr_close(struct inode *inode, struct file *file)
746 struct tun_struct *tun = file->private_data;
748 if (!tun)
749 return 0;
751 DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
753 tun_chr_fasync(-1, file, 0);
755 rtnl_lock();
757 /* Detach from net device */
758 file->private_data = NULL;
759 tun->attached = 0;
761 /* Drop read queue */
762 skb_queue_purge(&tun->readq);
764 if (!(tun->flags & TUN_PERSIST)) {
765 list_del(&tun->list);
766 unregister_netdevice(tun->dev);
769 rtnl_unlock();
771 return 0;
774 static const struct file_operations tun_fops = {
775 .owner = THIS_MODULE,
776 .llseek = no_llseek,
777 .read = do_sync_read,
778 .aio_read = tun_chr_aio_read,
779 .write = do_sync_write,
780 .aio_write = tun_chr_aio_write,
781 .poll = tun_chr_poll,
782 .ioctl = tun_chr_ioctl,
783 .open = tun_chr_open,
784 .release = tun_chr_close,
785 .fasync = tun_chr_fasync
788 static struct miscdevice tun_miscdev = {
789 .minor = TUN_MINOR,
790 .name = "tun",
791 .fops = &tun_fops,
794 /* ethtool interface */
796 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
798 cmd->supported = 0;
799 cmd->advertising = 0;
800 cmd->speed = SPEED_10;
801 cmd->duplex = DUPLEX_FULL;
802 cmd->port = PORT_TP;
803 cmd->phy_address = 0;
804 cmd->transceiver = XCVR_INTERNAL;
805 cmd->autoneg = AUTONEG_DISABLE;
806 cmd->maxtxpkt = 0;
807 cmd->maxrxpkt = 0;
808 return 0;
811 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
813 struct tun_struct *tun = netdev_priv(dev);
815 strcpy(info->driver, DRV_NAME);
816 strcpy(info->version, DRV_VERSION);
817 strcpy(info->fw_version, "N/A");
819 switch (tun->flags & TUN_TYPE_MASK) {
820 case TUN_TUN_DEV:
821 strcpy(info->bus_info, "tun");
822 break;
823 case TUN_TAP_DEV:
824 strcpy(info->bus_info, "tap");
825 break;
829 static u32 tun_get_msglevel(struct net_device *dev)
831 #ifdef TUN_DEBUG
832 struct tun_struct *tun = netdev_priv(dev);
833 return tun->debug;
834 #else
835 return -EOPNOTSUPP;
836 #endif
839 static void tun_set_msglevel(struct net_device *dev, u32 value)
841 #ifdef TUN_DEBUG
842 struct tun_struct *tun = netdev_priv(dev);
843 tun->debug = value;
844 #endif
847 static u32 tun_get_link(struct net_device *dev)
849 struct tun_struct *tun = netdev_priv(dev);
850 return tun->attached;
853 static u32 tun_get_rx_csum(struct net_device *dev)
855 struct tun_struct *tun = netdev_priv(dev);
856 return (tun->flags & TUN_NOCHECKSUM) == 0;
859 static int tun_set_rx_csum(struct net_device *dev, u32 data)
861 struct tun_struct *tun = netdev_priv(dev);
862 if (data)
863 tun->flags &= ~TUN_NOCHECKSUM;
864 else
865 tun->flags |= TUN_NOCHECKSUM;
866 return 0;
869 static const struct ethtool_ops tun_ethtool_ops = {
870 .get_settings = tun_get_settings,
871 .get_drvinfo = tun_get_drvinfo,
872 .get_msglevel = tun_get_msglevel,
873 .set_msglevel = tun_set_msglevel,
874 .get_link = tun_get_link,
875 .get_rx_csum = tun_get_rx_csum,
876 .set_rx_csum = tun_set_rx_csum
879 static int __init tun_init(void)
881 int ret = 0;
883 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
884 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
886 ret = misc_register(&tun_miscdev);
887 if (ret)
888 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
889 return ret;
892 static void tun_cleanup(void)
894 struct tun_struct *tun, *nxt;
896 misc_deregister(&tun_miscdev);
898 rtnl_lock();
899 list_for_each_entry_safe(tun, nxt, &tun_dev_list, list) {
900 DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
901 unregister_netdevice(tun->dev);
903 rtnl_unlock();
907 module_init(tun_init);
908 module_exit(tun_cleanup);
909 MODULE_DESCRIPTION(DRV_DESCRIPTION);
910 MODULE_AUTHOR(DRV_COPYRIGHT);
911 MODULE_LICENSE("GPL");
912 MODULE_ALIAS_MISCDEV(TUN_MINOR);