blob: 74d7f76d14a3e505667a2fb65dabcbd07935ce36 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * TUN - Universal TUN/TAP device driver.
3 * Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
4 *
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.
9 *
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.
14 *
15 * $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
16 */
17
18/*
19 * Changes:
20 *
Mike Kershawff4cc3a2005-09-01 17:40:05 -070021 * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
22 * Add TUNSETLINK ioctl to set the link encapsulation
23 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070024 * Mark Smith <markzzzsmith@yahoo.com.au>
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -070025 * Use random_ether_addr() for tap MAC address.
Linus Torvalds1da177e2005-04-16 15:20:36 -070026 *
27 * Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20
28 * Fixes in packet dropping, queue length setting and queue wakeup.
29 * Increased default tx queue length.
30 * Added ethtool API.
31 * Minor cleanups
32 *
33 * Daniel Podlejski <underley@underley.eu.org>
34 * Modifications for 2.3.99-pre5 kernel.
35 */
36
Joe Perches6b8a66e2011-03-02 07:18:10 +000037#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
38
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#define DRV_NAME "tun"
40#define DRV_VERSION "1.6"
41#define DRV_DESCRIPTION "Universal TUN/TAP device driver"
42#define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
43
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/module.h>
45#include <linux/errno.h>
46#include <linux/kernel.h>
47#include <linux/major.h>
48#include <linux/slab.h>
49#include <linux/poll.h>
50#include <linux/fcntl.h>
51#include <linux/init.h>
52#include <linux/skbuff.h>
53#include <linux/netdevice.h>
54#include <linux/etherdevice.h>
55#include <linux/miscdevice.h>
56#include <linux/ethtool.h>
57#include <linux/rtnetlink.h>
Arnd Bergmann50857e22009-11-06 22:52:32 -080058#include <linux/compat.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070059#include <linux/if.h>
60#include <linux/if_arp.h>
61#include <linux/if_ether.h>
62#include <linux/if_tun.h>
63#include <linux/crc32.h>
Pavel Emelyanovd647a592008-04-16 00:41:16 -070064#include <linux/nsproxy.h>
Rusty Russellf43798c2008-07-03 03:48:02 -070065#include <linux/virtio_net.h>
Michael S. Tsirkin99405162010-02-14 01:01:10 +000066#include <linux/rcupdate.h>
Eric W. Biederman881d9662007-09-17 11:56:21 -070067#include <net/net_namespace.h>
Pavel Emelyanov79d17602008-04-16 00:40:46 -070068#include <net/netns/generic.h>
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -080069#include <net/rtnetlink.h>
Herbert Xu33dccbb2009-02-05 21:25:32 -080070#include <net/sock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070071
72#include <asm/system.h>
73#include <asm/uaccess.h>
74
Rusty Russell14daa022008-04-12 18:48:58 -070075/* Uncomment to enable debugging */
76/* #define TUN_DEBUG 1 */
77
Linus Torvalds1da177e2005-04-16 15:20:36 -070078#ifdef TUN_DEBUG
79static int debug;
Rusty Russell14daa022008-04-12 18:48:58 -070080
Joe Perches6b8a66e2011-03-02 07:18:10 +000081#define tun_debug(level, tun, fmt, args...) \
82do { \
83 if (tun->debug) \
84 netdev_printk(level, tun->dev, fmt, ##args); \
85} while (0)
86#define DBG1(level, fmt, args...) \
87do { \
88 if (debug == 2) \
89 printk(level fmt, ##args); \
90} while (0)
Rusty Russell14daa022008-04-12 18:48:58 -070091#else
Joe Perches6b8a66e2011-03-02 07:18:10 +000092#define tun_debug(level, tun, fmt, args...) \
93do { \
94 if (0) \
95 netdev_printk(level, tun->dev, fmt, ##args); \
96} while (0)
97#define DBG1(level, fmt, args...) \
98do { \
99 if (0) \
100 printk(level fmt, ##args); \
101} while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102#endif
103
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700104#define FLT_EXACT_COUNT 8
105struct tap_filter {
106 unsigned int count; /* Number of addrs. Zero means disabled */
107 u32 mask[2]; /* Mask of the hashed addrs */
108 unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
109};
110
Eric W. Biederman631ab462009-01-20 11:00:40 +0000111struct tun_file {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000112 atomic_t count;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000113 struct tun_struct *tun;
Eric W. Biederman36b50ba2009-01-20 11:01:48 +0000114 struct net *net;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000115};
116
Herbert Xu33dccbb2009-02-05 21:25:32 -0800117struct tun_sock;
118
Rusty Russell14daa022008-04-12 18:48:58 -0700119struct tun_struct {
Eric W. Biederman631ab462009-01-20 11:00:40 +0000120 struct tun_file *tfile;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700121 unsigned int flags;
Rusty Russell14daa022008-04-12 18:48:58 -0700122 uid_t owner;
123 gid_t group;
124
Rusty Russell14daa022008-04-12 18:48:58 -0700125 struct net_device *dev;
Michał Mirosławc8f44af2011-11-15 15:29:55 +0000126 netdev_features_t set_features;
Michał Mirosław88255372011-04-19 06:13:10 +0000127#define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
128 NETIF_F_TSO6|NETIF_F_UFO)
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700129 struct fasync_struct *fasync;
Rusty Russell14daa022008-04-12 18:48:58 -0700130
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700131 struct tap_filter txflt;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800132 struct socket socket;
Eric Dumazet43815482010-04-29 11:01:49 +0000133 struct socket_wq wq;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200134
135 int vnet_hdr_sz;
136
Rusty Russell14daa022008-04-12 18:48:58 -0700137#ifdef TUN_DEBUG
138 int debug;
139#endif
140};
141
Herbert Xu33dccbb2009-02-05 21:25:32 -0800142struct tun_sock {
143 struct sock sk;
144 struct tun_struct *tun;
145};
146
147static inline struct tun_sock *tun_sk(struct sock *sk)
148{
149 return container_of(sk, struct tun_sock, sk);
150}
151
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000152static int tun_attach(struct tun_struct *tun, struct file *file)
153{
Eric W. Biederman631ab462009-01-20 11:00:40 +0000154 struct tun_file *tfile = file->private_data;
Eric W. Biederman38231b72009-01-20 11:02:28 +0000155 int err;
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000156
157 ASSERT_RTNL();
158
Eric W. Biederman38231b72009-01-20 11:02:28 +0000159 netif_tx_lock_bh(tun->dev);
160
161 err = -EINVAL;
162 if (tfile->tun)
163 goto out;
164
165 err = -EBUSY;
166 if (tun->tfile)
167 goto out;
168
169 err = 0;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000170 tfile->tun = tun;
171 tun->tfile = tfile;
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000172 tun->socket.file = file;
Nolan Leakebee31362010-07-27 13:53:43 +0000173 netif_carrier_on(tun->dev);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000174 dev_hold(tun->dev);
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000175 sock_hold(tun->socket.sk);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000176 atomic_inc(&tfile->count);
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000177
Eric W. Biederman38231b72009-01-20 11:02:28 +0000178out:
179 netif_tx_unlock_bh(tun->dev);
180 return err;
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000181}
182
Eric W. Biederman631ab462009-01-20 11:00:40 +0000183static void __tun_detach(struct tun_struct *tun)
184{
Eric W. Biederman631ab462009-01-20 11:00:40 +0000185 /* Detach from net device */
Eric W. Biederman38231b72009-01-20 11:02:28 +0000186 netif_tx_lock_bh(tun->dev);
Nolan Leakebee31362010-07-27 13:53:43 +0000187 netif_carrier_off(tun->dev);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000188 tun->tfile = NULL;
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000189 tun->socket.file = NULL;
Eric W. Biederman38231b72009-01-20 11:02:28 +0000190 netif_tx_unlock_bh(tun->dev);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000191
192 /* Drop read queue */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000193 skb_queue_purge(&tun->socket.sk->sk_receive_queue);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000194
195 /* Drop the extra count on the net device */
196 dev_put(tun->dev);
197}
198
199static void tun_detach(struct tun_struct *tun)
200{
201 rtnl_lock();
202 __tun_detach(tun);
203 rtnl_unlock();
Eric W. Biederman631ab462009-01-20 11:00:40 +0000204}
205
206static struct tun_struct *__tun_get(struct tun_file *tfile)
207{
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000208 struct tun_struct *tun = NULL;
209
210 if (atomic_inc_not_zero(&tfile->count))
211 tun = tfile->tun;
212
213 return tun;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000214}
215
216static struct tun_struct *tun_get(struct file *file)
217{
218 return __tun_get(file->private_data);
219}
220
221static void tun_put(struct tun_struct *tun)
222{
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000223 struct tun_file *tfile = tun->tfile;
224
225 if (atomic_dec_and_test(&tfile->count))
226 tun_detach(tfile->tun);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000227}
228
Joe Perches6b8a66e2011-03-02 07:18:10 +0000229/* TAP filtering */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700230static void addr_hash_set(u32 *mask, const u8 *addr)
231{
232 int n = ether_crc(ETH_ALEN, addr) >> 26;
233 mask[n >> 5] |= (1 << (n & 31));
234}
235
236static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
237{
238 int n = ether_crc(ETH_ALEN, addr) >> 26;
239 return mask[n >> 5] & (1 << (n & 31));
240}
241
242static int update_filter(struct tap_filter *filter, void __user *arg)
243{
244 struct { u8 u[ETH_ALEN]; } *addr;
245 struct tun_filter uf;
246 int err, alen, n, nexact;
247
248 if (copy_from_user(&uf, arg, sizeof(uf)))
249 return -EFAULT;
250
251 if (!uf.count) {
252 /* Disabled */
253 filter->count = 0;
254 return 0;
255 }
256
257 alen = ETH_ALEN * uf.count;
258 addr = kmalloc(alen, GFP_KERNEL);
259 if (!addr)
260 return -ENOMEM;
261
262 if (copy_from_user(addr, arg + sizeof(uf), alen)) {
263 err = -EFAULT;
264 goto done;
265 }
266
267 /* The filter is updated without holding any locks. Which is
268 * perfectly safe. We disable it first and in the worst
269 * case we'll accept a few undesired packets. */
270 filter->count = 0;
271 wmb();
272
273 /* Use first set of addresses as an exact filter */
274 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
275 memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
276
277 nexact = n;
278
Alex Williamsoncfbf84f2009-02-08 17:49:17 -0800279 /* Remaining multicast addresses are hashed,
280 * unicast will leave the filter disabled. */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700281 memset(filter->mask, 0, sizeof(filter->mask));
Alex Williamsoncfbf84f2009-02-08 17:49:17 -0800282 for (; n < uf.count; n++) {
283 if (!is_multicast_ether_addr(addr[n].u)) {
284 err = 0; /* no filter */
285 goto done;
286 }
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700287 addr_hash_set(filter->mask, addr[n].u);
Alex Williamsoncfbf84f2009-02-08 17:49:17 -0800288 }
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700289
290 /* For ALLMULTI just set the mask to all ones.
291 * This overrides the mask populated above. */
292 if ((uf.flags & TUN_FLT_ALLMULTI))
293 memset(filter->mask, ~0, sizeof(filter->mask));
294
295 /* Now enable the filter */
296 wmb();
297 filter->count = nexact;
298
299 /* Return the number of exact filters */
300 err = nexact;
301
302done:
303 kfree(addr);
304 return err;
305}
306
307/* Returns: 0 - drop, !=0 - accept */
308static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
309{
310 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
311 * at this point. */
312 struct ethhdr *eh = (struct ethhdr *) skb->data;
313 int i;
314
315 /* Exact match */
316 for (i = 0; i < filter->count; i++)
317 if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
318 return 1;
319
320 /* Inexact match (multicast only) */
321 if (is_multicast_ether_addr(eh->h_dest))
322 return addr_hash_test(filter->mask, eh->h_dest);
323
324 return 0;
325}
326
327/*
328 * Checks whether the packet is accepted or not.
329 * Returns: 0 - drop, !=0 - accept
330 */
331static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
332{
333 if (!filter->count)
334 return 1;
335
336 return run_filter(filter, skb);
337}
338
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339/* Network device part of the driver */
340
Jeff Garzik7282d492006-09-13 14:30:00 -0400341static const struct ethtool_ops tun_ethtool_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000343/* Net device detach from fd. */
344static void tun_net_uninit(struct net_device *dev)
345{
346 struct tun_struct *tun = netdev_priv(dev);
347 struct tun_file *tfile = tun->tfile;
348
349 /* Inform the methods they need to stop using the dev.
350 */
351 if (tfile) {
Eric Dumazet43815482010-04-29 11:01:49 +0000352 wake_up_all(&tun->wq.wait);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000353 if (atomic_dec_and_test(&tfile->count))
354 __tun_detach(tun);
355 }
356}
357
Herbert Xu9c3fea62009-04-18 14:15:52 +0000358static void tun_free_netdev(struct net_device *dev)
359{
360 struct tun_struct *tun = netdev_priv(dev);
361
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000362 sk_release_kernel(tun->socket.sk);
Herbert Xu9c3fea62009-04-18 14:15:52 +0000363}
364
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365/* Net device open. */
366static int tun_net_open(struct net_device *dev)
367{
368 netif_start_queue(dev);
369 return 0;
370}
371
372/* Net device close. */
373static int tun_net_close(struct net_device *dev)
374{
375 netif_stop_queue(dev);
376 return 0;
377}
378
379/* Net device start xmit */
Stephen Hemminger424efe92009-08-31 19:50:51 +0000380static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381{
382 struct tun_struct *tun = netdev_priv(dev);
383
Joe Perches6b8a66e2011-03-02 07:18:10 +0000384 tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385
386 /* Drop packet if interface is not attached */
Eric W. Biederman631ab462009-01-20 11:00:40 +0000387 if (!tun->tfile)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 goto drop;
389
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700390 /* Drop if the filter does not like it.
391 * This is a noop if the filter is disabled.
392 * Filter can be enabled only for the TAP devices. */
393 if (!check_filter(&tun->txflt, skb))
394 goto drop;
395
Michael S. Tsirkin99405162010-02-14 01:01:10 +0000396 if (tun->socket.sk->sk_filter &&
397 sk_filter(tun->socket.sk, skb))
398 goto drop;
399
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000400 if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 if (!(tun->flags & TUN_ONE_QUEUE)) {
402 /* Normal queueing mode. */
403 /* Packet scheduler handles dropping of further packets. */
404 netif_stop_queue(dev);
405
406 /* We won't see all dropped packets individually, so overrun
407 * error is more appropriate. */
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700408 dev->stats.tx_fifo_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 } else {
410 /* Single queue mode.
411 * Driver handles dropping of all packets itself. */
412 goto drop;
413 }
414 }
415
Michael S. Tsirkin0110d6f2010-04-13 04:59:44 +0000416 /* Orphan the skb - required as we might hang on to it
417 * for indefinite time. */
418 skb_orphan(skb);
419
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700420 /* Enqueue packet */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000421 skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422
423 /* Notify and wake up reader process */
424 if (tun->flags & TUN_FASYNC)
425 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
Eric Dumazet43815482010-04-29 11:01:49 +0000426 wake_up_interruptible_poll(&tun->wq.wait, POLLIN |
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000427 POLLRDNORM | POLLRDBAND);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000428 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429
430drop:
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700431 dev->stats.tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432 kfree_skb(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000433 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434}
435
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700436static void tun_net_mclist(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437{
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700438 /*
439 * This callback is supposed to deal with mc filter in
440 * _rx_ path and has nothing to do with the _tx_ path.
441 * In rx path we always accept everything userspace gives us.
442 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443}
444
Ed Swierk4885a502007-09-16 12:21:38 -0700445#define MIN_MTU 68
446#define MAX_MTU 65535
447
448static int
449tun_net_change_mtu(struct net_device *dev, int new_mtu)
450{
451 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
452 return -EINVAL;
453 dev->mtu = new_mtu;
454 return 0;
455}
456
Michał Mirosławc8f44af2011-11-15 15:29:55 +0000457static netdev_features_t tun_net_fix_features(struct net_device *dev,
458 netdev_features_t features)
Michał Mirosław88255372011-04-19 06:13:10 +0000459{
460 struct tun_struct *tun = netdev_priv(dev);
461
462 return (features & tun->set_features) | (features & ~TUN_USER_FEATURES);
463}
Neil Hormanbebd0972011-06-15 05:25:01 +0000464#ifdef CONFIG_NET_POLL_CONTROLLER
465static void tun_poll_controller(struct net_device *dev)
466{
467 /*
468 * Tun only receives frames when:
469 * 1) the char device endpoint gets data from user space
470 * 2) the tun socket gets a sendmsg call from user space
471 * Since both of those are syncronous operations, we are guaranteed
472 * never to have pending data when we poll for it
473 * so theres nothing to do here but return.
474 * We need this though so netpoll recognizes us as an interface that
475 * supports polling, which enables bridge devices in virt setups to
476 * still use netconsole
477 */
478 return;
479}
480#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800481static const struct net_device_ops tun_netdev_ops = {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000482 .ndo_uninit = tun_net_uninit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800483 .ndo_open = tun_net_open,
484 .ndo_stop = tun_net_close,
Stephen Hemminger00829822008-11-20 20:14:53 -0800485 .ndo_start_xmit = tun_net_xmit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800486 .ndo_change_mtu = tun_net_change_mtu,
Michał Mirosław88255372011-04-19 06:13:10 +0000487 .ndo_fix_features = tun_net_fix_features,
Neil Hormanbebd0972011-06-15 05:25:01 +0000488#ifdef CONFIG_NET_POLL_CONTROLLER
489 .ndo_poll_controller = tun_poll_controller,
490#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800491};
492
493static const struct net_device_ops tap_netdev_ops = {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000494 .ndo_uninit = tun_net_uninit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800495 .ndo_open = tun_net_open,
496 .ndo_stop = tun_net_close,
Stephen Hemminger00829822008-11-20 20:14:53 -0800497 .ndo_start_xmit = tun_net_xmit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800498 .ndo_change_mtu = tun_net_change_mtu,
Michał Mirosław88255372011-04-19 06:13:10 +0000499 .ndo_fix_features = tun_net_fix_features,
Jiri Pirkoafc4b132011-08-16 06:29:01 +0000500 .ndo_set_rx_mode = tun_net_mclist,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800501 .ndo_set_mac_address = eth_mac_addr,
502 .ndo_validate_addr = eth_validate_addr,
Neil Hormanbebd0972011-06-15 05:25:01 +0000503#ifdef CONFIG_NET_POLL_CONTROLLER
504 .ndo_poll_controller = tun_poll_controller,
505#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800506};
507
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508/* Initialize net device. */
509static void tun_net_init(struct net_device *dev)
510{
511 struct tun_struct *tun = netdev_priv(dev);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400512
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 switch (tun->flags & TUN_TYPE_MASK) {
514 case TUN_TUN_DEV:
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800515 dev->netdev_ops = &tun_netdev_ops;
516
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 /* Point-to-Point TUN Device */
518 dev->hard_header_len = 0;
519 dev->addr_len = 0;
520 dev->mtu = 1500;
521
522 /* Zero header length */
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400523 dev->type = ARPHRD_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
525 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
526 break;
527
528 case TUN_TAP_DEV:
Kusanagi Kouichi7a0a9602008-12-29 18:23:28 -0800529 dev->netdev_ops = &tap_netdev_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 /* Ethernet TAP Device */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700531 ether_setup(dev);
Neil Horman550fd082011-07-26 06:05:38 +0000532 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533
Danny Kukawkaf2cedb62012-02-15 06:45:39 +0000534 eth_hw_addr_random(dev);
Brian Braunstein36226a82007-04-26 01:00:55 -0700535
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
537 break;
538 }
539}
540
541/* Character device part */
542
543/* Poll */
544static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400545{
Eric W. Biedermanb2430de2009-01-20 11:03:21 +0000546 struct tun_file *tfile = file->private_data;
547 struct tun_struct *tun = __tun_get(tfile);
Mariusz Kozlowski3c8a9c62009-07-05 19:48:35 +0000548 struct sock *sk;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800549 unsigned int mask = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550
551 if (!tun)
Eric W. Biedermaneac9e902009-01-20 10:59:05 +0000552 return POLLERR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000554 sk = tun->socket.sk;
Mariusz Kozlowski3c8a9c62009-07-05 19:48:35 +0000555
Joe Perches6b8a66e2011-03-02 07:18:10 +0000556 tun_debug(KERN_INFO, tun, "tun_chr_poll\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557
Eric Dumazet43815482010-04-29 11:01:49 +0000558 poll_wait(file, &tun->wq.wait, wait);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400559
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000560 if (!skb_queue_empty(&sk->sk_receive_queue))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 mask |= POLLIN | POLLRDNORM;
562
Herbert Xu33dccbb2009-02-05 21:25:32 -0800563 if (sock_writeable(sk) ||
564 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
565 sock_writeable(sk)))
566 mask |= POLLOUT | POLLWRNORM;
567
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000568 if (tun->dev->reg_state != NETREG_REGISTERED)
569 mask = POLLERR;
570
Eric W. Biederman631ab462009-01-20 11:00:40 +0000571 tun_put(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 return mask;
573}
574
Rusty Russellf42157c2008-08-15 15:15:10 -0700575/* prepad is the amount to reserve at front. len is length after that.
576 * linear is a hint as to how much to copy (usually headers). */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000577static struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
578 size_t prepad, size_t len,
579 size_t linear, int noblock)
Rusty Russellf42157c2008-08-15 15:15:10 -0700580{
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000581 struct sock *sk = tun->socket.sk;
Rusty Russellf42157c2008-08-15 15:15:10 -0700582 struct sk_buff *skb;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800583 int err;
Rusty Russellf42157c2008-08-15 15:15:10 -0700584
Herbert Xu82862742010-05-24 00:14:10 -0700585 sock_update_classid(sk);
586
Rusty Russellf42157c2008-08-15 15:15:10 -0700587 /* Under a page? Don't bother with paged skb. */
Herbert Xu0eca93b2009-04-14 02:09:43 -0700588 if (prepad + len < PAGE_SIZE || !linear)
Herbert Xu33dccbb2009-02-05 21:25:32 -0800589 linear = len;
Rusty Russellf42157c2008-08-15 15:15:10 -0700590
Herbert Xu33dccbb2009-02-05 21:25:32 -0800591 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
592 &err);
Rusty Russellf42157c2008-08-15 15:15:10 -0700593 if (!skb)
Herbert Xu33dccbb2009-02-05 21:25:32 -0800594 return ERR_PTR(err);
Rusty Russellf42157c2008-08-15 15:15:10 -0700595
596 skb_reserve(skb, prepad);
597 skb_put(skb, linear);
Herbert Xu33dccbb2009-02-05 21:25:32 -0800598 skb->data_len = len - linear;
599 skb->len += len - linear;
Rusty Russellf42157c2008-08-15 15:15:10 -0700600
601 return skb;
602}
603
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604/* Get packet from user space buffer */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000605static ssize_t tun_get_user(struct tun_struct *tun,
606 const struct iovec *iv, size_t count,
607 int noblock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608{
Harvey Harrison09640e62009-02-01 00:45:17 -0800609 struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 struct sk_buff *skb;
stephen hemmingera504b862011-06-08 14:33:07 +0000611 size_t len = count, align = NET_SKB_PAD;
Rusty Russellf43798c2008-07-03 03:48:02 -0700612 struct virtio_net_hdr gso = { 0 };
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000613 int offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614
615 if (!(tun->flags & TUN_NO_PI)) {
616 if ((len -= sizeof(pi)) > count)
617 return -EINVAL;
618
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000619 if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620 return -EFAULT;
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000621 offset += sizeof(pi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 }
623
Rusty Russellf43798c2008-07-03 03:48:02 -0700624 if (tun->flags & TUN_VNET_HDR) {
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200625 if ((len -= tun->vnet_hdr_sz) > count)
Rusty Russellf43798c2008-07-03 03:48:02 -0700626 return -EINVAL;
627
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000628 if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso)))
Rusty Russellf43798c2008-07-03 03:48:02 -0700629 return -EFAULT;
630
Herbert Xu49091222009-06-08 00:20:01 -0700631 if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
632 gso.csum_start + gso.csum_offset + 2 > gso.hdr_len)
633 gso.hdr_len = gso.csum_start + gso.csum_offset + 2;
634
Rusty Russellf43798c2008-07-03 03:48:02 -0700635 if (gso.hdr_len > len)
636 return -EINVAL;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200637 offset += tun->vnet_hdr_sz;
Rusty Russellf43798c2008-07-03 03:48:02 -0700638 }
639
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700640 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
stephen hemmingera504b862011-06-08 14:33:07 +0000641 align += NET_IP_ALIGN;
Herbert Xu0eca93b2009-04-14 02:09:43 -0700642 if (unlikely(len < ETH_HLEN ||
643 (gso.hdr_len && gso.hdr_len < ETH_HLEN)))
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700644 return -EINVAL;
645 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400646
Herbert Xu33dccbb2009-02-05 21:25:32 -0800647 skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock);
648 if (IS_ERR(skb)) {
649 if (PTR_ERR(skb) != -EAGAIN)
650 tun->dev->stats.rx_dropped++;
651 return PTR_ERR(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 }
653
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000654 if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) {
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700655 tun->dev->stats.rx_dropped++;
Dave Jones8f227572006-03-11 18:49:13 -0800656 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 return -EFAULT;
Dave Jones8f227572006-03-11 18:49:13 -0800658 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659
Rusty Russellf43798c2008-07-03 03:48:02 -0700660 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
661 if (!skb_partial_csum_set(skb, gso.csum_start,
662 gso.csum_offset)) {
663 tun->dev->stats.rx_frame_errors++;
664 kfree_skb(skb);
665 return -EINVAL;
666 }
Michał Mirosław88255372011-04-19 06:13:10 +0000667 }
Rusty Russellf43798c2008-07-03 03:48:02 -0700668
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 switch (tun->flags & TUN_TYPE_MASK) {
670 case TUN_TUN_DEV:
Ang Way Chuangf09f7ee2008-06-17 21:10:33 -0700671 if (tun->flags & TUN_NO_PI) {
672 switch (skb->data[0] & 0xf0) {
673 case 0x40:
674 pi.proto = htons(ETH_P_IP);
675 break;
676 case 0x60:
677 pi.proto = htons(ETH_P_IPV6);
678 break;
679 default:
680 tun->dev->stats.rx_dropped++;
681 kfree_skb(skb);
682 return -EINVAL;
683 }
684 }
685
Arnaldo Carvalho de Melo459a98e2007-03-19 15:30:44 -0700686 skb_reset_mac_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 skb->protocol = pi.proto;
Arnaldo Carvalho de Melo4c13eb62007-04-25 17:40:23 -0700688 skb->dev = tun->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 break;
690 case TUN_TAP_DEV:
691 skb->protocol = eth_type_trans(skb, tun->dev);
692 break;
Joe Perches6403eab2011-06-03 11:51:20 +0000693 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694
Rusty Russellf43798c2008-07-03 03:48:02 -0700695 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
696 pr_debug("GSO!\n");
697 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
698 case VIRTIO_NET_HDR_GSO_TCPV4:
699 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
700 break;
701 case VIRTIO_NET_HDR_GSO_TCPV6:
702 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
703 break;
Sridhar Samudralae36aa252009-07-14 14:21:04 +0000704 case VIRTIO_NET_HDR_GSO_UDP:
705 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
706 break;
Rusty Russellf43798c2008-07-03 03:48:02 -0700707 default:
708 tun->dev->stats.rx_frame_errors++;
709 kfree_skb(skb);
710 return -EINVAL;
711 }
712
713 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
714 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
715
716 skb_shinfo(skb)->gso_size = gso.gso_size;
717 if (skb_shinfo(skb)->gso_size == 0) {
718 tun->dev->stats.rx_frame_errors++;
719 kfree_skb(skb);
720 return -EINVAL;
721 }
722
723 /* Header must be checked, and gso_segs computed. */
724 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
725 skb_shinfo(skb)->gso_segs = 0;
726 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400727
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 netif_rx_ni(skb);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400729
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700730 tun->dev->stats.rx_packets++;
731 tun->dev->stats.rx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
733 return count;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400734}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700736static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
737 unsigned long count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738{
Herbert Xu33dccbb2009-02-05 21:25:32 -0800739 struct file *file = iocb->ki_filp;
Herbert Xuab46d772009-02-14 20:46:39 -0800740 struct tun_struct *tun = tun_get(file);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000741 ssize_t result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
743 if (!tun)
744 return -EBADFD;
745
Joe Perches6b8a66e2011-03-02 07:18:10 +0000746 tun_debug(KERN_INFO, tun, "tun_chr_write %ld\n", count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000748 result = tun_get_user(tun, iv, iov_length(iv, count),
Herbert Xu33dccbb2009-02-05 21:25:32 -0800749 file->f_flags & O_NONBLOCK);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000750
751 tun_put(tun);
752 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753}
754
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755/* Put packet to the user space buffer */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000756static ssize_t tun_put_user(struct tun_struct *tun,
757 struct sk_buff *skb,
758 const struct iovec *iv, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759{
760 struct tun_pi pi = { 0, skb->protocol };
761 ssize_t total = 0;
762
763 if (!(tun->flags & TUN_NO_PI)) {
764 if ((len -= sizeof(pi)) < 0)
765 return -EINVAL;
766
767 if (len < skb->len) {
768 /* Packet will be striped */
769 pi.flags |= TUN_PKT_STRIP;
770 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400771
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000772 if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773 return -EFAULT;
774 total += sizeof(pi);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400775 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776
Rusty Russellf43798c2008-07-03 03:48:02 -0700777 if (tun->flags & TUN_VNET_HDR) {
778 struct virtio_net_hdr gso = { 0 }; /* no info leak */
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200779 if ((len -= tun->vnet_hdr_sz) < 0)
Rusty Russellf43798c2008-07-03 03:48:02 -0700780 return -EINVAL;
781
782 if (skb_is_gso(skb)) {
783 struct skb_shared_info *sinfo = skb_shinfo(skb);
784
785 /* This is a hint as to how much should be linear. */
786 gso.hdr_len = skb_headlen(skb);
787 gso.gso_size = sinfo->gso_size;
788 if (sinfo->gso_type & SKB_GSO_TCPV4)
789 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
790 else if (sinfo->gso_type & SKB_GSO_TCPV6)
791 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
Sridhar Samudralae36aa252009-07-14 14:21:04 +0000792 else if (sinfo->gso_type & SKB_GSO_UDP)
793 gso.gso_type = VIRTIO_NET_HDR_GSO_UDP;
Michael S. Tsirkinef3db4a2010-07-21 04:32:45 +0000794 else {
Joe Perches6b8a66e2011-03-02 07:18:10 +0000795 pr_err("unexpected GSO type: "
Michael S. Tsirkinef3db4a2010-07-21 04:32:45 +0000796 "0x%x, gso_size %d, hdr_len %d\n",
797 sinfo->gso_type, gso.gso_size,
798 gso.hdr_len);
799 print_hex_dump(KERN_ERR, "tun: ",
800 DUMP_PREFIX_NONE,
801 16, 1, skb->head,
802 min((int)gso.hdr_len, 64), true);
803 WARN_ON_ONCE(1);
804 return -EINVAL;
805 }
Rusty Russellf43798c2008-07-03 03:48:02 -0700806 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
807 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
808 } else
809 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
810
811 if (skb->ip_summed == CHECKSUM_PARTIAL) {
812 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
Michał Mirosław55508d62010-12-14 15:24:08 +0000813 gso.csum_start = skb_checksum_start_offset(skb);
Rusty Russellf43798c2008-07-03 03:48:02 -0700814 gso.csum_offset = skb->csum_offset;
Jason Wang10a8d942011-06-10 00:56:17 +0000815 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
816 gso.flags = VIRTIO_NET_HDR_F_DATA_VALID;
Rusty Russellf43798c2008-07-03 03:48:02 -0700817 } /* else everything is zero */
818
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000819 if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
820 sizeof(gso))))
Rusty Russellf43798c2008-07-03 03:48:02 -0700821 return -EFAULT;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200822 total += tun->vnet_hdr_sz;
Rusty Russellf43798c2008-07-03 03:48:02 -0700823 }
824
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 len = min_t(int, skb->len, len);
826
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000827 skb_copy_datagram_const_iovec(skb, 0, iv, total, len);
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000828 total += skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700830 tun->dev->stats.tx_packets++;
831 tun->dev->stats.tx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832
833 return total;
834}
835
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000836static ssize_t tun_do_read(struct tun_struct *tun,
837 struct kiocb *iocb, const struct iovec *iv,
838 ssize_t len, int noblock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 DECLARE_WAITQUEUE(wait, current);
841 struct sk_buff *skb;
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000842 ssize_t ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843
Joe Perches6b8a66e2011-03-02 07:18:10 +0000844 tun_debug(KERN_INFO, tun, "tun_chr_read\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845
Amos Kong61a5ff12011-06-09 00:27:10 -0700846 if (unlikely(!noblock))
847 add_wait_queue(&tun->wq.wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 while (len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 current->state = TASK_INTERRUPTIBLE;
850
851 /* Read frames from the queue */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000852 if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) {
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000853 if (noblock) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854 ret = -EAGAIN;
855 break;
856 }
857 if (signal_pending(current)) {
858 ret = -ERESTARTSYS;
859 break;
860 }
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000861 if (tun->dev->reg_state != NETREG_REGISTERED) {
862 ret = -EIO;
863 break;
864 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865
866 /* Nothing to read, let's sleep */
867 schedule();
868 continue;
869 }
870 netif_wake_queue(tun->dev);
871
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000872 ret = tun_put_user(tun, skb, iv, len);
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700873 kfree_skb(skb);
874 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875 }
876
877 current->state = TASK_RUNNING;
Amos Kong61a5ff12011-06-09 00:27:10 -0700878 if (unlikely(!noblock))
879 remove_wait_queue(&tun->wq.wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000881 return ret;
882}
883
884static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
885 unsigned long count, loff_t pos)
886{
887 struct file *file = iocb->ki_filp;
888 struct tun_file *tfile = file->private_data;
889 struct tun_struct *tun = __tun_get(tfile);
890 ssize_t len, ret;
891
892 if (!tun)
893 return -EBADFD;
894 len = iov_length(iv, count);
895 if (len < 0) {
896 ret = -EINVAL;
897 goto out;
898 }
899
900 ret = tun_do_read(tun, iocb, iv, len, file->f_flags & O_NONBLOCK);
901 ret = min_t(ssize_t, ret, len);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000902out:
903 tun_put(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904 return ret;
905}
906
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907static void tun_setup(struct net_device *dev)
908{
909 struct tun_struct *tun = netdev_priv(dev);
910
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911 tun->owner = -1;
Guido Guenther8c644622007-07-02 22:50:25 -0700912 tun->group = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914 dev->ethtool_ops = &tun_ethtool_ops;
Herbert Xu9c3fea62009-04-18 14:15:52 +0000915 dev->destructor = tun_free_netdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916}
917
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -0800918/* Trivial set of netlink ops to allow deleting tun or tap
919 * device with netlink.
920 */
921static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
922{
923 return -EINVAL;
924}
925
926static struct rtnl_link_ops tun_link_ops __read_mostly = {
927 .kind = DRV_NAME,
928 .priv_size = sizeof(struct tun_struct),
929 .setup = tun_setup,
930 .validate = tun_validate,
931};
932
Herbert Xu33dccbb2009-02-05 21:25:32 -0800933static void tun_sock_write_space(struct sock *sk)
934{
935 struct tun_struct *tun;
Eric Dumazet43815482010-04-29 11:01:49 +0000936 wait_queue_head_t *wqueue;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800937
938 if (!sock_writeable(sk))
939 return;
940
Herbert Xu33dccbb2009-02-05 21:25:32 -0800941 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
942 return;
943
Eric Dumazet43815482010-04-29 11:01:49 +0000944 wqueue = sk_sleep(sk);
945 if (wqueue && waitqueue_active(wqueue))
946 wake_up_interruptible_sync_poll(wqueue, POLLOUT |
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000947 POLLWRNORM | POLLWRBAND);
Herbert Xuc722c622009-06-03 21:45:55 -0700948
Vitaliy Gusev80924e52009-12-25 07:17:43 +0000949 tun = tun_sk(sk)->tun;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800950 kill_fasync(&tun->fasync, SIGIO, POLL_OUT);
951}
952
953static void tun_sock_destruct(struct sock *sk)
954{
Vitaliy Gusev80924e52009-12-25 07:17:43 +0000955 free_netdev(tun_sk(sk)->tun->dev);
Herbert Xu33dccbb2009-02-05 21:25:32 -0800956}
957
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000958static int tun_sendmsg(struct kiocb *iocb, struct socket *sock,
959 struct msghdr *m, size_t total_len)
960{
961 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
962 return tun_get_user(tun, m->msg_iov, total_len,
963 m->msg_flags & MSG_DONTWAIT);
964}
965
966static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
967 struct msghdr *m, size_t total_len,
968 int flags)
969{
970 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
971 int ret;
972 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
973 return -EINVAL;
974 ret = tun_do_read(tun, iocb, m->msg_iov, total_len,
975 flags & MSG_DONTWAIT);
976 if (ret > total_len) {
977 m->msg_flags |= MSG_TRUNC;
978 ret = flags & MSG_TRUNC ? ret : total_len;
979 }
980 return ret;
981}
982
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000983static int tun_release(struct socket *sock)
984{
985 if (sock->sk)
986 sock_put(sock->sk);
987 return 0;
988}
989
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000990/* Ops structure to mimic raw sockets with tun */
991static const struct proto_ops tun_socket_ops = {
992 .sendmsg = tun_sendmsg,
993 .recvmsg = tun_recvmsg,
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000994 .release = tun_release,
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000995};
996
Herbert Xu33dccbb2009-02-05 21:25:32 -0800997static struct proto tun_proto = {
998 .name = "tun",
999 .owner = THIS_MODULE,
1000 .obj_size = sizeof(struct tun_sock),
1001};
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001002
David Woodhouse980c9e82009-05-09 22:54:21 -07001003static int tun_flags(struct tun_struct *tun)
1004{
1005 int flags = 0;
1006
1007 if (tun->flags & TUN_TUN_DEV)
1008 flags |= IFF_TUN;
1009 else
1010 flags |= IFF_TAP;
1011
1012 if (tun->flags & TUN_NO_PI)
1013 flags |= IFF_NO_PI;
1014
1015 if (tun->flags & TUN_ONE_QUEUE)
1016 flags |= IFF_ONE_QUEUE;
1017
1018 if (tun->flags & TUN_VNET_HDR)
1019 flags |= IFF_VNET_HDR;
1020
1021 return flags;
1022}
1023
1024static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr,
1025 char *buf)
1026{
1027 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1028 return sprintf(buf, "0x%x\n", tun_flags(tun));
1029}
1030
1031static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr,
1032 char *buf)
1033{
1034 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1035 return sprintf(buf, "%d\n", tun->owner);
1036}
1037
1038static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
1039 char *buf)
1040{
1041 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1042 return sprintf(buf, "%d\n", tun->group);
1043}
1044
1045static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
1046static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL);
1047static DEVICE_ATTR(group, 0444, tun_show_group, NULL);
1048
Pavel Emelyanovd647a592008-04-16 00:41:16 -07001049static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001050{
Herbert Xu33dccbb2009-02-05 21:25:32 -08001051 struct sock *sk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052 struct tun_struct *tun;
1053 struct net_device *dev;
1054 int err;
1055
Eric W. Biederman74a3e5a2009-01-20 10:56:20 +00001056 dev = __dev_get_by_name(net, ifr->ifr_name);
1057 if (dev) {
Paul Moore2b980db2009-08-28 18:12:43 -04001058 const struct cred *cred = current_cred();
1059
David Woodhousef85ba782009-04-27 03:23:54 -07001060 if (ifr->ifr_flags & IFF_TUN_EXCL)
1061 return -EBUSY;
Eric W. Biederman74a3e5a2009-01-20 10:56:20 +00001062 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
1063 tun = netdev_priv(dev);
1064 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
1065 tun = netdev_priv(dev);
1066 else
1067 return -EINVAL;
1068
Paul Moore2b980db2009-08-28 18:12:43 -04001069 if (((tun->owner != -1 && cred->euid != tun->owner) ||
1070 (tun->group != -1 && !in_egroup_p(tun->group))) &&
1071 !capable(CAP_NET_ADMIN))
1072 return -EPERM;
Linus Torvaldsd7e96602009-09-14 10:37:28 -07001073 err = security_tun_dev_attach(tun->socket.sk);
Paul Moore2b980db2009-08-28 18:12:43 -04001074 if (err < 0)
1075 return err;
1076
Eric W. Biedermana7385ba2009-01-20 10:57:48 +00001077 err = tun_attach(tun, file);
1078 if (err < 0)
1079 return err;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001080 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 else {
1082 char *name;
1083 unsigned long flags = 0;
1084
David Woodhouseca6bb5d2006-06-22 16:07:52 -07001085 if (!capable(CAP_NET_ADMIN))
1086 return -EPERM;
Paul Moore2b980db2009-08-28 18:12:43 -04001087 err = security_tun_dev_create();
1088 if (err < 0)
1089 return err;
David Woodhouseca6bb5d2006-06-22 16:07:52 -07001090
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091 /* Set dev type */
1092 if (ifr->ifr_flags & IFF_TUN) {
1093 /* TUN device */
1094 flags |= TUN_TUN_DEV;
1095 name = "tun%d";
1096 } else if (ifr->ifr_flags & IFF_TAP) {
1097 /* TAP device */
1098 flags |= TUN_TAP_DEV;
1099 name = "tap%d";
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001100 } else
Kusanagi Kouichi36989b92009-09-16 21:36:13 +00001101 return -EINVAL;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001102
Linus Torvalds1da177e2005-04-16 15:20:36 -07001103 if (*ifr->ifr_name)
1104 name = ifr->ifr_name;
1105
1106 dev = alloc_netdev(sizeof(struct tun_struct), name,
1107 tun_setup);
1108 if (!dev)
1109 return -ENOMEM;
1110
Pavel Emelyanovfc54c652008-04-16 00:41:53 -07001111 dev_net_set(dev, net);
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001112 dev->rtnl_link_ops = &tun_link_ops;
Stephen Hemminger758e43b2008-11-19 22:10:37 -08001113
Linus Torvalds1da177e2005-04-16 15:20:36 -07001114 tun = netdev_priv(dev);
1115 tun->dev = dev;
1116 tun->flags = flags;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001117 tun->txflt.count = 0;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001118 tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119
Herbert Xu33dccbb2009-02-05 21:25:32 -08001120 err = -ENOMEM;
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001121 sk = sk_alloc(&init_net, AF_UNSPEC, GFP_KERNEL, &tun_proto);
Herbert Xu33dccbb2009-02-05 21:25:32 -08001122 if (!sk)
1123 goto err_free_dev;
1124
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001125 sk_change_net(sk, net);
Eric Dumazet43815482010-04-29 11:01:49 +00001126 tun->socket.wq = &tun->wq;
1127 init_waitqueue_head(&tun->wq.wait);
Michael S. Tsirkin05c28282010-01-14 06:17:09 +00001128 tun->socket.ops = &tun_socket_ops;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001129 sock_init_data(&tun->socket, sk);
1130 sk->sk_write_space = tun_sock_write_space;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001131 sk->sk_sndbuf = INT_MAX;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001132
Vitaliy Gusev80924e52009-12-25 07:17:43 +00001133 tun_sk(sk)->tun = tun;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001134
Paul Moore2b980db2009-08-28 18:12:43 -04001135 security_tun_dev_post_create(sk);
1136
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 tun_net_init(dev);
1138
Michał Mirosław88255372011-04-19 06:13:10 +00001139 dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST |
1140 TUN_USER_FEATURES;
1141 dev->features = dev->hw_features;
1142
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143 err = register_netdevice(tun->dev);
1144 if (err < 0)
Herbert Xu9c3fea62009-04-18 14:15:52 +00001145 goto err_free_sk;
1146
David Woodhouse980c9e82009-05-09 22:54:21 -07001147 if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) ||
1148 device_create_file(&tun->dev->dev, &dev_attr_owner) ||
1149 device_create_file(&tun->dev->dev, &dev_attr_group))
Joe Perches6b8a66e2011-03-02 07:18:10 +00001150 pr_err("Failed to create tun sysfs files\n");
David Woodhouse980c9e82009-05-09 22:54:21 -07001151
Herbert Xu9c3fea62009-04-18 14:15:52 +00001152 sk->sk_destruct = tun_sock_destruct;
Eric W. Biedermana7385ba2009-01-20 10:57:48 +00001153
1154 err = tun_attach(tun, file);
1155 if (err < 0)
Herbert Xu9c3fea62009-04-18 14:15:52 +00001156 goto failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001157 }
1158
Joe Perches6b8a66e2011-03-02 07:18:10 +00001159 tun_debug(KERN_INFO, tun, "tun_set_iff\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160
1161 if (ifr->ifr_flags & IFF_NO_PI)
1162 tun->flags |= TUN_NO_PI;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -08001163 else
1164 tun->flags &= ~TUN_NO_PI;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001165
1166 if (ifr->ifr_flags & IFF_ONE_QUEUE)
1167 tun->flags |= TUN_ONE_QUEUE;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -08001168 else
1169 tun->flags &= ~TUN_ONE_QUEUE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170
Rusty Russellf43798c2008-07-03 03:48:02 -07001171 if (ifr->ifr_flags & IFF_VNET_HDR)
1172 tun->flags |= TUN_VNET_HDR;
1173 else
1174 tun->flags &= ~TUN_VNET_HDR;
1175
Max Krasnyanskye35259a2008-07-10 16:59:11 -07001176 /* Make sure persistent devices do not get stuck in
1177 * xoff state.
1178 */
1179 if (netif_running(tun->dev))
1180 netif_wake_queue(tun->dev);
1181
Linus Torvalds1da177e2005-04-16 15:20:36 -07001182 strcpy(ifr->ifr_name, tun->dev->name);
1183 return 0;
1184
Herbert Xu33dccbb2009-02-05 21:25:32 -08001185 err_free_sk:
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001186 tun_free_netdev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187 err_free_dev:
1188 free_netdev(dev);
1189 failed:
1190 return err;
1191}
1192
Herbert Xu876bfd42009-08-06 14:22:44 +00001193static int tun_get_iff(struct net *net, struct tun_struct *tun,
1194 struct ifreq *ifr)
Mark McLoughline3b99552008-08-15 15:09:56 -07001195{
Joe Perches6b8a66e2011-03-02 07:18:10 +00001196 tun_debug(KERN_INFO, tun, "tun_get_iff\n");
Mark McLoughline3b99552008-08-15 15:09:56 -07001197
1198 strcpy(ifr->ifr_name, tun->dev->name);
1199
David Woodhouse980c9e82009-05-09 22:54:21 -07001200 ifr->ifr_flags = tun_flags(tun);
Mark McLoughline3b99552008-08-15 15:09:56 -07001201
1202 return 0;
1203}
1204
Rusty Russell5228ddc2008-07-03 03:46:16 -07001205/* This is like a cut-down ethtool ops, except done via tun fd so no
1206 * privs required. */
Michał Mirosław88255372011-04-19 06:13:10 +00001207static int set_offload(struct tun_struct *tun, unsigned long arg)
Rusty Russell5228ddc2008-07-03 03:46:16 -07001208{
Michał Mirosławc8f44af2011-11-15 15:29:55 +00001209 netdev_features_t features = 0;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001210
1211 if (arg & TUN_F_CSUM) {
Michał Mirosław88255372011-04-19 06:13:10 +00001212 features |= NETIF_F_HW_CSUM;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001213 arg &= ~TUN_F_CSUM;
1214
1215 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
1216 if (arg & TUN_F_TSO_ECN) {
1217 features |= NETIF_F_TSO_ECN;
1218 arg &= ~TUN_F_TSO_ECN;
1219 }
1220 if (arg & TUN_F_TSO4)
1221 features |= NETIF_F_TSO;
1222 if (arg & TUN_F_TSO6)
1223 features |= NETIF_F_TSO6;
1224 arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
1225 }
Sridhar Samudralae36aa252009-07-14 14:21:04 +00001226
1227 if (arg & TUN_F_UFO) {
1228 features |= NETIF_F_UFO;
1229 arg &= ~TUN_F_UFO;
1230 }
Rusty Russell5228ddc2008-07-03 03:46:16 -07001231 }
1232
1233 /* This gives the user a way to test for new features in future by
1234 * trying to set them. */
1235 if (arg)
1236 return -EINVAL;
1237
Michał Mirosław88255372011-04-19 06:13:10 +00001238 tun->set_features = features;
1239 netdev_update_features(tun->dev);
Rusty Russell5228ddc2008-07-03 03:46:16 -07001240
1241 return 0;
1242}
1243
Arnd Bergmann50857e22009-11-06 22:52:32 -08001244static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
1245 unsigned long arg, int ifreq_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001246{
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001247 struct tun_file *tfile = file->private_data;
Eric W. Biederman631ab462009-01-20 11:00:40 +00001248 struct tun_struct *tun;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001249 void __user* argp = (void __user*)arg;
Michael S. Tsirkin99405162010-02-14 01:01:10 +00001250 struct sock_fprog fprog;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001251 struct ifreq ifr;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001252 int sndbuf;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001253 int vnet_hdr_sz;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001254 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001255
1256 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
Arnd Bergmann50857e22009-11-06 22:52:32 -08001257 if (copy_from_user(&ifr, argp, ifreq_len))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258 return -EFAULT;
1259
Eric W. Biederman631ab462009-01-20 11:00:40 +00001260 if (cmd == TUNGETFEATURES) {
1261 /* Currently this just means: "what IFF flags are valid?".
1262 * This is needed because we never checked for invalid flags on
1263 * TUNSETIFF. */
1264 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
1265 IFF_VNET_HDR,
1266 (unsigned int __user*)argp);
1267 }
1268
Herbert Xu876bfd42009-08-06 14:22:44 +00001269 rtnl_lock();
1270
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001271 tun = __tun_get(tfile);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001272 if (cmd == TUNSETIFF && !tun) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001273 ifr.ifr_name[IFNAMSIZ-1] = '\0';
1274
Herbert Xu876bfd42009-08-06 14:22:44 +00001275 ret = tun_set_iff(tfile->net, file, &ifr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001276
Herbert Xu876bfd42009-08-06 14:22:44 +00001277 if (ret)
1278 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279
Arnd Bergmann50857e22009-11-06 22:52:32 -08001280 if (copy_to_user(argp, &ifr, ifreq_len))
Herbert Xu876bfd42009-08-06 14:22:44 +00001281 ret = -EFAULT;
1282 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283 }
1284
Herbert Xu876bfd42009-08-06 14:22:44 +00001285 ret = -EBADFD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286 if (!tun)
Herbert Xu876bfd42009-08-06 14:22:44 +00001287 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001288
Joe Perches6b8a66e2011-03-02 07:18:10 +00001289 tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %d\n", cmd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290
Eric W. Biederman631ab462009-01-20 11:00:40 +00001291 ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292 switch (cmd) {
Mark McLoughline3b99552008-08-15 15:09:56 -07001293 case TUNGETIFF:
Herbert Xu876bfd42009-08-06 14:22:44 +00001294 ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
Mark McLoughline3b99552008-08-15 15:09:56 -07001295 if (ret)
Eric W. Biederman631ab462009-01-20 11:00:40 +00001296 break;
Mark McLoughline3b99552008-08-15 15:09:56 -07001297
Arnd Bergmann50857e22009-11-06 22:52:32 -08001298 if (copy_to_user(argp, &ifr, ifreq_len))
Eric W. Biederman631ab462009-01-20 11:00:40 +00001299 ret = -EFAULT;
Mark McLoughline3b99552008-08-15 15:09:56 -07001300 break;
1301
Linus Torvalds1da177e2005-04-16 15:20:36 -07001302 case TUNSETNOCSUM:
1303 /* Disable/Enable checksum */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304
Michał Mirosław88255372011-04-19 06:13:10 +00001305 /* [unimplemented] */
1306 tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n",
Joe Perches6b8a66e2011-03-02 07:18:10 +00001307 arg ? "disabled" : "enabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308 break;
1309
1310 case TUNSETPERSIST:
1311 /* Disable/Enable persist mode */
1312 if (arg)
1313 tun->flags |= TUN_PERSIST;
1314 else
1315 tun->flags &= ~TUN_PERSIST;
1316
Joe Perches6b8a66e2011-03-02 07:18:10 +00001317 tun_debug(KERN_INFO, tun, "persist %s\n",
1318 arg ? "enabled" : "disabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001319 break;
1320
1321 case TUNSETOWNER:
1322 /* Set owner of the device */
1323 tun->owner = (uid_t) arg;
1324
Joe Perches6b8a66e2011-03-02 07:18:10 +00001325 tun_debug(KERN_INFO, tun, "owner set to %d\n", tun->owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001326 break;
1327
Guido Guenther8c644622007-07-02 22:50:25 -07001328 case TUNSETGROUP:
1329 /* Set group of the device */
1330 tun->group= (gid_t) arg;
1331
Joe Perches6b8a66e2011-03-02 07:18:10 +00001332 tun_debug(KERN_INFO, tun, "group set to %d\n", tun->group);
Guido Guenther8c644622007-07-02 22:50:25 -07001333 break;
1334
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001335 case TUNSETLINK:
1336 /* Only allow setting the type when the interface is down */
1337 if (tun->dev->flags & IFF_UP) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001338 tun_debug(KERN_INFO, tun,
1339 "Linktype set failed because interface is up\n");
David S. Miller48abfe02008-04-23 19:37:58 -07001340 ret = -EBUSY;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001341 } else {
1342 tun->dev->type = (int) arg;
Joe Perches6b8a66e2011-03-02 07:18:10 +00001343 tun_debug(KERN_INFO, tun, "linktype set to %d\n",
1344 tun->dev->type);
David S. Miller48abfe02008-04-23 19:37:58 -07001345 ret = 0;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001346 }
Eric W. Biederman631ab462009-01-20 11:00:40 +00001347 break;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001348
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349#ifdef TUN_DEBUG
1350 case TUNSETDEBUG:
1351 tun->debug = arg;
1352 break;
1353#endif
Rusty Russell5228ddc2008-07-03 03:46:16 -07001354 case TUNSETOFFLOAD:
Michał Mirosław88255372011-04-19 06:13:10 +00001355 ret = set_offload(tun, arg);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001356 break;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001357
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001358 case TUNSETTXFILTER:
1359 /* Can be set only for TAPs */
Eric W. Biederman631ab462009-01-20 11:00:40 +00001360 ret = -EINVAL;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001361 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
Eric W. Biederman631ab462009-01-20 11:00:40 +00001362 break;
Harvey Harrisonc0e5a8c2008-07-16 12:45:34 -07001363 ret = update_filter(&tun->txflt, (void __user *)arg);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001364 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365
1366 case SIOCGIFHWADDR:
Uwe Kleine-Königb5950762010-11-01 15:38:34 -04001367 /* Get hw address */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001368 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1369 ifr.ifr_hwaddr.sa_family = tun->dev->type;
Arnd Bergmann50857e22009-11-06 22:52:32 -08001370 if (copy_to_user(argp, &ifr, ifreq_len))
Eric W. Biederman631ab462009-01-20 11:00:40 +00001371 ret = -EFAULT;
1372 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373
1374 case SIOCSIFHWADDR:
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001375 /* Set hw address */
Joe Perches6b8a66e2011-03-02 07:18:10 +00001376 tun_debug(KERN_DEBUG, tun, "set hw address: %pM\n",
1377 ifr.ifr_hwaddr.sa_data);
Kim B. Heino40102372008-02-29 12:26:21 -08001378
Kim B. Heino40102372008-02-29 12:26:21 -08001379 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001380 break;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001381
1382 case TUNGETSNDBUF:
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001383 sndbuf = tun->socket.sk->sk_sndbuf;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001384 if (copy_to_user(argp, &sndbuf, sizeof(sndbuf)))
1385 ret = -EFAULT;
1386 break;
1387
1388 case TUNSETSNDBUF:
1389 if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) {
1390 ret = -EFAULT;
1391 break;
1392 }
1393
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001394 tun->socket.sk->sk_sndbuf = sndbuf;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001395 break;
1396
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001397 case TUNGETVNETHDRSZ:
1398 vnet_hdr_sz = tun->vnet_hdr_sz;
1399 if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz)))
1400 ret = -EFAULT;
1401 break;
1402
1403 case TUNSETVNETHDRSZ:
1404 if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) {
1405 ret = -EFAULT;
1406 break;
1407 }
1408 if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) {
1409 ret = -EINVAL;
1410 break;
1411 }
1412
1413 tun->vnet_hdr_sz = vnet_hdr_sz;
1414 break;
1415
Michael S. Tsirkin99405162010-02-14 01:01:10 +00001416 case TUNATTACHFILTER:
1417 /* Can be set only for TAPs */
1418 ret = -EINVAL;
1419 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1420 break;
1421 ret = -EFAULT;
1422 if (copy_from_user(&fprog, argp, sizeof(fprog)))
1423 break;
1424
1425 ret = sk_attach_filter(&fprog, tun->socket.sk);
1426 break;
1427
1428 case TUNDETACHFILTER:
1429 /* Can be set only for TAPs */
1430 ret = -EINVAL;
1431 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1432 break;
1433 ret = sk_detach_filter(tun->socket.sk);
1434 break;
1435
Linus Torvalds1da177e2005-04-16 15:20:36 -07001436 default:
Eric W. Biederman631ab462009-01-20 11:00:40 +00001437 ret = -EINVAL;
1438 break;
Joe Perchesee289b62010-05-17 22:47:34 -07001439 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001440
Herbert Xu876bfd42009-08-06 14:22:44 +00001441unlock:
1442 rtnl_unlock();
1443 if (tun)
1444 tun_put(tun);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001445 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446}
1447
Arnd Bergmann50857e22009-11-06 22:52:32 -08001448static long tun_chr_ioctl(struct file *file,
1449 unsigned int cmd, unsigned long arg)
1450{
1451 return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq));
1452}
1453
1454#ifdef CONFIG_COMPAT
1455static long tun_chr_compat_ioctl(struct file *file,
1456 unsigned int cmd, unsigned long arg)
1457{
1458 switch (cmd) {
1459 case TUNSETIFF:
1460 case TUNGETIFF:
1461 case TUNSETTXFILTER:
1462 case TUNGETSNDBUF:
1463 case TUNSETSNDBUF:
1464 case SIOCGIFHWADDR:
1465 case SIOCSIFHWADDR:
1466 arg = (unsigned long)compat_ptr(arg);
1467 break;
1468 default:
1469 arg = (compat_ulong_t)arg;
1470 break;
1471 }
1472
1473 /*
1474 * compat_ifreq is shorter than ifreq, so we must not access beyond
1475 * the end of that structure. All fields that are used in this
1476 * driver are compatible though, we don't need to convert the
1477 * contents.
1478 */
1479 return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq));
1480}
1481#endif /* CONFIG_COMPAT */
1482
Linus Torvalds1da177e2005-04-16 15:20:36 -07001483static int tun_chr_fasync(int fd, struct file *file, int on)
1484{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001485 struct tun_struct *tun = tun_get(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001486 int ret;
1487
1488 if (!tun)
1489 return -EBADFD;
1490
Joe Perches6b8a66e2011-03-02 07:18:10 +00001491 tun_debug(KERN_INFO, tun, "tun_chr_fasync %d\n", on);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492
1493 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
Jonathan Corbet9d319522008-06-19 15:50:37 -06001494 goto out;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001495
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496 if (on) {
Eric W. Biederman609d7fa2006-10-02 02:17:15 -07001497 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 if (ret)
Jonathan Corbet9d319522008-06-19 15:50:37 -06001499 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001500 tun->flags |= TUN_FASYNC;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001501 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -07001502 tun->flags &= ~TUN_FASYNC;
Jonathan Corbet9d319522008-06-19 15:50:37 -06001503 ret = 0;
1504out:
Eric W. Biederman631ab462009-01-20 11:00:40 +00001505 tun_put(tun);
Jonathan Corbet9d319522008-06-19 15:50:37 -06001506 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001507}
1508
1509static int tun_chr_open(struct inode *inode, struct file * file)
1510{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001511 struct tun_file *tfile;
Thomas Gleixnerdeed49f2009-10-14 01:19:46 -07001512
Joe Perches6b8a66e2011-03-02 07:18:10 +00001513 DBG1(KERN_INFO, "tunX: tun_chr_open\n");
Eric W. Biederman631ab462009-01-20 11:00:40 +00001514
1515 tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
1516 if (!tfile)
1517 return -ENOMEM;
Eric W. Biedermanc70f1822009-01-20 11:07:17 +00001518 atomic_set(&tfile->count, 0);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001519 tfile->tun = NULL;
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001520 tfile->net = get_net(current->nsproxy->net_ns);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001521 file->private_data = tfile;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001522 return 0;
1523}
1524
1525static int tun_chr_close(struct inode *inode, struct file *file)
1526{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001527 struct tun_file *tfile = file->private_data;
Eric W. Biedermanf0a4d0e2009-06-08 00:44:31 -07001528 struct tun_struct *tun;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001529
Eric W. Biedermanf0a4d0e2009-06-08 00:44:31 -07001530 tun = __tun_get(tfile);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001531 if (tun) {
Herbert Xud23e4362009-07-02 23:03:55 +00001532 struct net_device *dev = tun->dev;
1533
Joe Perches6b8a66e2011-03-02 07:18:10 +00001534 tun_debug(KERN_INFO, tun, "tun_chr_close\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001535
Eric W. Biederman631ab462009-01-20 11:00:40 +00001536 __tun_detach(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001537
Daniel Mack3ad2f3f2010-02-03 08:01:28 +08001538 /* If desirable, unregister the netdevice. */
Herbert Xud23e4362009-07-02 23:03:55 +00001539 if (!(tun->flags & TUN_PERSIST)) {
1540 rtnl_lock();
1541 if (dev->reg_state == NETREG_REGISTERED)
1542 unregister_netdevice(dev);
1543 rtnl_unlock();
1544 }
Eric W. Biederman631ab462009-01-20 11:00:40 +00001545 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546
Herbert Xu9c3fea62009-04-18 14:15:52 +00001547 tun = tfile->tun;
1548 if (tun)
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001549 sock_put(tun->socket.sk);
Herbert Xu9c3fea62009-04-18 14:15:52 +00001550
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001551 put_net(tfile->net);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001552 kfree(tfile);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001553
1554 return 0;
1555}
1556
Arjan van de Vend54b1fd2007-02-12 00:55:34 -08001557static const struct file_operations tun_fops = {
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001558 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001559 .llseek = no_llseek,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -07001560 .read = do_sync_read,
1561 .aio_read = tun_chr_aio_read,
1562 .write = do_sync_write,
1563 .aio_write = tun_chr_aio_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564 .poll = tun_chr_poll,
Arnd Bergmann50857e22009-11-06 22:52:32 -08001565 .unlocked_ioctl = tun_chr_ioctl,
1566#ifdef CONFIG_COMPAT
1567 .compat_ioctl = tun_chr_compat_ioctl,
1568#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569 .open = tun_chr_open,
1570 .release = tun_chr_close,
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001571 .fasync = tun_chr_fasync
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572};
1573
1574static struct miscdevice tun_miscdev = {
1575 .minor = TUN_MINOR,
1576 .name = "tun",
Kay Sieverse454cea2009-09-18 23:01:12 +02001577 .nodename = "net/tun",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578 .fops = &tun_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001579};
1580
1581/* ethtool interface */
1582
1583static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1584{
1585 cmd->supported = 0;
1586 cmd->advertising = 0;
David Decotigny70739492011-04-27 18:32:40 +00001587 ethtool_cmd_speed_set(cmd, SPEED_10);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588 cmd->duplex = DUPLEX_FULL;
1589 cmd->port = PORT_TP;
1590 cmd->phy_address = 0;
1591 cmd->transceiver = XCVR_INTERNAL;
1592 cmd->autoneg = AUTONEG_DISABLE;
1593 cmd->maxtxpkt = 0;
1594 cmd->maxrxpkt = 0;
1595 return 0;
1596}
1597
1598static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1599{
1600 struct tun_struct *tun = netdev_priv(dev);
1601
Rick Jones33a5ba12011-11-15 14:59:53 +00001602 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1603 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001604
1605 switch (tun->flags & TUN_TYPE_MASK) {
1606 case TUN_TUN_DEV:
Rick Jones33a5ba12011-11-15 14:59:53 +00001607 strlcpy(info->bus_info, "tun", sizeof(info->bus_info));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608 break;
1609 case TUN_TAP_DEV:
Rick Jones33a5ba12011-11-15 14:59:53 +00001610 strlcpy(info->bus_info, "tap", sizeof(info->bus_info));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001611 break;
1612 }
1613}
1614
1615static u32 tun_get_msglevel(struct net_device *dev)
1616{
1617#ifdef TUN_DEBUG
1618 struct tun_struct *tun = netdev_priv(dev);
1619 return tun->debug;
1620#else
1621 return -EOPNOTSUPP;
1622#endif
1623}
1624
1625static void tun_set_msglevel(struct net_device *dev, u32 value)
1626{
1627#ifdef TUN_DEBUG
1628 struct tun_struct *tun = netdev_priv(dev);
1629 tun->debug = value;
1630#endif
1631}
1632
Jeff Garzik7282d492006-09-13 14:30:00 -04001633static const struct ethtool_ops tun_ethtool_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001634 .get_settings = tun_get_settings,
1635 .get_drvinfo = tun_get_drvinfo,
1636 .get_msglevel = tun_get_msglevel,
1637 .set_msglevel = tun_set_msglevel,
Nolan Leakebee31362010-07-27 13:53:43 +00001638 .get_link = ethtool_op_get_link,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001639};
1640
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001641
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642static int __init tun_init(void)
1643{
1644 int ret = 0;
1645
Joe Perches6b8a66e2011-03-02 07:18:10 +00001646 pr_info("%s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1647 pr_info("%s\n", DRV_COPYRIGHT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001648
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001649 ret = rtnl_link_register(&tun_link_ops);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001650 if (ret) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001651 pr_err("Can't register link_ops\n");
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001652 goto err_linkops;
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001653 }
1654
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655 ret = misc_register(&tun_miscdev);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001656 if (ret) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001657 pr_err("Can't register misc device %d\n", TUN_MINOR);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001658 goto err_misc;
1659 }
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001660 return 0;
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001661err_misc:
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001662 rtnl_link_unregister(&tun_link_ops);
1663err_linkops:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664 return ret;
1665}
1666
1667static void tun_cleanup(void)
1668{
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001669 misc_deregister(&tun_miscdev);
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001670 rtnl_link_unregister(&tun_link_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001671}
1672
Michael S. Tsirkin05c28282010-01-14 06:17:09 +00001673/* Get an underlying socket object from tun file. Returns error unless file is
1674 * attached to a device. The returned object works like a packet socket, it
1675 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1676 * holding a reference to the file for as long as the socket is in use. */
1677struct socket *tun_get_socket(struct file *file)
1678{
1679 struct tun_struct *tun;
1680 if (file->f_op != &tun_fops)
1681 return ERR_PTR(-EINVAL);
1682 tun = tun_get(file);
1683 if (!tun)
1684 return ERR_PTR(-EBADFD);
1685 tun_put(tun);
1686 return &tun->socket;
1687}
1688EXPORT_SYMBOL_GPL(tun_get_socket);
1689
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690module_init(tun_init);
1691module_exit(tun_cleanup);
1692MODULE_DESCRIPTION(DRV_DESCRIPTION);
1693MODULE_AUTHOR(DRV_COPYRIGHT);
1694MODULE_LICENSE("GPL");
1695MODULE_ALIAS_MISCDEV(TUN_MINOR);
Kay Sievers578454f2010-05-20 18:07:20 +02001696MODULE_ALIAS("devname:net/tun");