blob: bb8c72c79c6f31c9c932b2960df6a2c2f009a08e [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
Linus Torvalds1da177e2005-04-16 15:20:36 -070072#include <asm/uaccess.h>
73
Rusty Russell14daa022008-04-12 18:48:58 -070074/* Uncomment to enable debugging */
75/* #define TUN_DEBUG 1 */
76
Linus Torvalds1da177e2005-04-16 15:20:36 -070077#ifdef TUN_DEBUG
78static int debug;
Rusty Russell14daa022008-04-12 18:48:58 -070079
Joe Perches6b8a66e2011-03-02 07:18:10 +000080#define tun_debug(level, tun, fmt, args...) \
81do { \
82 if (tun->debug) \
83 netdev_printk(level, tun->dev, fmt, ##args); \
84} while (0)
85#define DBG1(level, fmt, args...) \
86do { \
87 if (debug == 2) \
88 printk(level fmt, ##args); \
89} while (0)
Rusty Russell14daa022008-04-12 18:48:58 -070090#else
Joe Perches6b8a66e2011-03-02 07:18:10 +000091#define tun_debug(level, tun, fmt, args...) \
92do { \
93 if (0) \
94 netdev_printk(level, tun->dev, fmt, ##args); \
95} while (0)
96#define DBG1(level, fmt, args...) \
97do { \
98 if (0) \
99 printk(level fmt, ##args); \
100} while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101#endif
102
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700103#define FLT_EXACT_COUNT 8
104struct tap_filter {
105 unsigned int count; /* Number of addrs. Zero means disabled */
106 u32 mask[2]; /* Mask of the hashed addrs */
107 unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
108};
109
Eric W. Biederman631ab462009-01-20 11:00:40 +0000110struct tun_file {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000111 atomic_t count;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000112 struct tun_struct *tun;
Eric W. Biederman36b50ba2009-01-20 11:01:48 +0000113 struct net *net;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000114};
115
Herbert Xu33dccbb2009-02-05 21:25:32 -0800116struct tun_sock;
117
Rusty Russell14daa022008-04-12 18:48:58 -0700118struct tun_struct {
Eric W. Biederman631ab462009-01-20 11:00:40 +0000119 struct tun_file *tfile;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700120 unsigned int flags;
Rusty Russell14daa022008-04-12 18:48:58 -0700121 uid_t owner;
122 gid_t group;
123
Rusty Russell14daa022008-04-12 18:48:58 -0700124 struct net_device *dev;
Michał Mirosławc8f44af2011-11-15 15:29:55 +0000125 netdev_features_t set_features;
Michał Mirosław88255372011-04-19 06:13:10 +0000126#define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
127 NETIF_F_TSO6|NETIF_F_UFO)
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700128 struct fasync_struct *fasync;
Rusty Russell14daa022008-04-12 18:48:58 -0700129
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700130 struct tap_filter txflt;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800131 struct socket socket;
Eric Dumazet43815482010-04-29 11:01:49 +0000132 struct socket_wq wq;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200133
134 int vnet_hdr_sz;
135
Rusty Russell14daa022008-04-12 18:48:58 -0700136#ifdef TUN_DEBUG
137 int debug;
138#endif
139};
140
Herbert Xu33dccbb2009-02-05 21:25:32 -0800141struct tun_sock {
142 struct sock sk;
143 struct tun_struct *tun;
144};
145
146static inline struct tun_sock *tun_sk(struct sock *sk)
147{
148 return container_of(sk, struct tun_sock, sk);
149}
150
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000151static int tun_attach(struct tun_struct *tun, struct file *file)
152{
Eric W. Biederman631ab462009-01-20 11:00:40 +0000153 struct tun_file *tfile = file->private_data;
Eric W. Biederman38231b72009-01-20 11:02:28 +0000154 int err;
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000155
156 ASSERT_RTNL();
157
Eric W. Biederman38231b72009-01-20 11:02:28 +0000158 netif_tx_lock_bh(tun->dev);
159
160 err = -EINVAL;
161 if (tfile->tun)
162 goto out;
163
164 err = -EBUSY;
165 if (tun->tfile)
166 goto out;
167
168 err = 0;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000169 tfile->tun = tun;
170 tun->tfile = tfile;
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000171 tun->socket.file = file;
Nolan Leakebee31362010-07-27 13:53:43 +0000172 netif_carrier_on(tun->dev);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000173 dev_hold(tun->dev);
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000174 sock_hold(tun->socket.sk);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000175 atomic_inc(&tfile->count);
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000176
Eric W. Biederman38231b72009-01-20 11:02:28 +0000177out:
178 netif_tx_unlock_bh(tun->dev);
179 return err;
Eric W. Biedermana7385ba2009-01-20 10:57:48 +0000180}
181
Eric W. Biederman631ab462009-01-20 11:00:40 +0000182static void __tun_detach(struct tun_struct *tun)
183{
Eric W. Biederman631ab462009-01-20 11:00:40 +0000184 /* Detach from net device */
Eric W. Biederman38231b72009-01-20 11:02:28 +0000185 netif_tx_lock_bh(tun->dev);
Nolan Leakebee31362010-07-27 13:53:43 +0000186 netif_carrier_off(tun->dev);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000187 tun->tfile = NULL;
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000188 tun->socket.file = NULL;
Eric W. Biederman38231b72009-01-20 11:02:28 +0000189 netif_tx_unlock_bh(tun->dev);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000190
191 /* Drop read queue */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000192 skb_queue_purge(&tun->socket.sk->sk_receive_queue);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000193
194 /* Drop the extra count on the net device */
195 dev_put(tun->dev);
196}
197
198static void tun_detach(struct tun_struct *tun)
199{
200 rtnl_lock();
201 __tun_detach(tun);
202 rtnl_unlock();
Eric W. Biederman631ab462009-01-20 11:00:40 +0000203}
204
205static struct tun_struct *__tun_get(struct tun_file *tfile)
206{
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000207 struct tun_struct *tun = NULL;
208
209 if (atomic_inc_not_zero(&tfile->count))
210 tun = tfile->tun;
211
212 return tun;
Eric W. Biederman631ab462009-01-20 11:00:40 +0000213}
214
215static struct tun_struct *tun_get(struct file *file)
216{
217 return __tun_get(file->private_data);
218}
219
220static void tun_put(struct tun_struct *tun)
221{
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000222 struct tun_file *tfile = tun->tfile;
223
224 if (atomic_dec_and_test(&tfile->count))
225 tun_detach(tfile->tun);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000226}
227
Joe Perches6b8a66e2011-03-02 07:18:10 +0000228/* TAP filtering */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700229static void addr_hash_set(u32 *mask, const u8 *addr)
230{
231 int n = ether_crc(ETH_ALEN, addr) >> 26;
232 mask[n >> 5] |= (1 << (n & 31));
233}
234
235static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
236{
237 int n = ether_crc(ETH_ALEN, addr) >> 26;
238 return mask[n >> 5] & (1 << (n & 31));
239}
240
241static int update_filter(struct tap_filter *filter, void __user *arg)
242{
243 struct { u8 u[ETH_ALEN]; } *addr;
244 struct tun_filter uf;
245 int err, alen, n, nexact;
246
247 if (copy_from_user(&uf, arg, sizeof(uf)))
248 return -EFAULT;
249
250 if (!uf.count) {
251 /* Disabled */
252 filter->count = 0;
253 return 0;
254 }
255
256 alen = ETH_ALEN * uf.count;
257 addr = kmalloc(alen, GFP_KERNEL);
258 if (!addr)
259 return -ENOMEM;
260
261 if (copy_from_user(addr, arg + sizeof(uf), alen)) {
262 err = -EFAULT;
263 goto done;
264 }
265
266 /* The filter is updated without holding any locks. Which is
267 * perfectly safe. We disable it first and in the worst
268 * case we'll accept a few undesired packets. */
269 filter->count = 0;
270 wmb();
271
272 /* Use first set of addresses as an exact filter */
273 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
274 memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
275
276 nexact = n;
277
Alex Williamsoncfbf84f2009-02-08 17:49:17 -0800278 /* Remaining multicast addresses are hashed,
279 * unicast will leave the filter disabled. */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700280 memset(filter->mask, 0, sizeof(filter->mask));
Alex Williamsoncfbf84f2009-02-08 17:49:17 -0800281 for (; n < uf.count; n++) {
282 if (!is_multicast_ether_addr(addr[n].u)) {
283 err = 0; /* no filter */
284 goto done;
285 }
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700286 addr_hash_set(filter->mask, addr[n].u);
Alex Williamsoncfbf84f2009-02-08 17:49:17 -0800287 }
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700288
289 /* For ALLMULTI just set the mask to all ones.
290 * This overrides the mask populated above. */
291 if ((uf.flags & TUN_FLT_ALLMULTI))
292 memset(filter->mask, ~0, sizeof(filter->mask));
293
294 /* Now enable the filter */
295 wmb();
296 filter->count = nexact;
297
298 /* Return the number of exact filters */
299 err = nexact;
300
301done:
302 kfree(addr);
303 return err;
304}
305
306/* Returns: 0 - drop, !=0 - accept */
307static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
308{
309 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
310 * at this point. */
311 struct ethhdr *eh = (struct ethhdr *) skb->data;
312 int i;
313
314 /* Exact match */
315 for (i = 0; i < filter->count; i++)
316 if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
317 return 1;
318
319 /* Inexact match (multicast only) */
320 if (is_multicast_ether_addr(eh->h_dest))
321 return addr_hash_test(filter->mask, eh->h_dest);
322
323 return 0;
324}
325
326/*
327 * Checks whether the packet is accepted or not.
328 * Returns: 0 - drop, !=0 - accept
329 */
330static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
331{
332 if (!filter->count)
333 return 1;
334
335 return run_filter(filter, skb);
336}
337
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338/* Network device part of the driver */
339
Jeff Garzik7282d492006-09-13 14:30:00 -0400340static const struct ethtool_ops tun_ethtool_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000342/* Net device detach from fd. */
343static void tun_net_uninit(struct net_device *dev)
344{
345 struct tun_struct *tun = netdev_priv(dev);
346 struct tun_file *tfile = tun->tfile;
347
348 /* Inform the methods they need to stop using the dev.
349 */
350 if (tfile) {
Eric Dumazet43815482010-04-29 11:01:49 +0000351 wake_up_all(&tun->wq.wait);
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000352 if (atomic_dec_and_test(&tfile->count))
353 __tun_detach(tun);
354 }
355}
356
Herbert Xu9c3fea62009-04-18 14:15:52 +0000357static void tun_free_netdev(struct net_device *dev)
358{
359 struct tun_struct *tun = netdev_priv(dev);
360
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000361 sk_release_kernel(tun->socket.sk);
Herbert Xu9c3fea62009-04-18 14:15:52 +0000362}
363
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364/* Net device open. */
365static int tun_net_open(struct net_device *dev)
366{
367 netif_start_queue(dev);
368 return 0;
369}
370
371/* Net device close. */
372static int tun_net_close(struct net_device *dev)
373{
374 netif_stop_queue(dev);
375 return 0;
376}
377
378/* Net device start xmit */
Stephen Hemminger424efe92009-08-31 19:50:51 +0000379static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380{
381 struct tun_struct *tun = netdev_priv(dev);
382
Joe Perches6b8a66e2011-03-02 07:18:10 +0000383 tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384
385 /* Drop packet if interface is not attached */
Eric W. Biederman631ab462009-01-20 11:00:40 +0000386 if (!tun->tfile)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 goto drop;
388
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700389 /* Drop if the filter does not like it.
390 * This is a noop if the filter is disabled.
391 * Filter can be enabled only for the TAP devices. */
392 if (!check_filter(&tun->txflt, skb))
393 goto drop;
394
Michael S. Tsirkin99405162010-02-14 01:01:10 +0000395 if (tun->socket.sk->sk_filter &&
396 sk_filter(tun->socket.sk, skb))
397 goto drop;
398
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000399 if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 if (!(tun->flags & TUN_ONE_QUEUE)) {
401 /* Normal queueing mode. */
402 /* Packet scheduler handles dropping of further packets. */
403 netif_stop_queue(dev);
404
405 /* We won't see all dropped packets individually, so overrun
406 * error is more appropriate. */
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700407 dev->stats.tx_fifo_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 } else {
409 /* Single queue mode.
410 * Driver handles dropping of all packets itself. */
411 goto drop;
412 }
413 }
414
Michael S. Tsirkin0110d6f2010-04-13 04:59:44 +0000415 /* Orphan the skb - required as we might hang on to it
416 * for indefinite time. */
417 skb_orphan(skb);
418
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700419 /* Enqueue packet */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000420 skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
422 /* Notify and wake up reader process */
423 if (tun->flags & TUN_FASYNC)
424 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
Eric Dumazet43815482010-04-29 11:01:49 +0000425 wake_up_interruptible_poll(&tun->wq.wait, POLLIN |
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000426 POLLRDNORM | POLLRDBAND);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000427 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428
429drop:
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700430 dev->stats.tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 kfree_skb(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000432 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433}
434
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700435static void tun_net_mclist(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436{
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700437 /*
438 * This callback is supposed to deal with mc filter in
439 * _rx_ path and has nothing to do with the _tx_ path.
440 * In rx path we always accept everything userspace gives us.
441 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442}
443
Ed Swierk4885a502007-09-16 12:21:38 -0700444#define MIN_MTU 68
445#define MAX_MTU 65535
446
447static int
448tun_net_change_mtu(struct net_device *dev, int new_mtu)
449{
450 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
451 return -EINVAL;
452 dev->mtu = new_mtu;
453 return 0;
454}
455
Michał Mirosławc8f44af2011-11-15 15:29:55 +0000456static netdev_features_t tun_net_fix_features(struct net_device *dev,
457 netdev_features_t features)
Michał Mirosław88255372011-04-19 06:13:10 +0000458{
459 struct tun_struct *tun = netdev_priv(dev);
460
461 return (features & tun->set_features) | (features & ~TUN_USER_FEATURES);
462}
Neil Hormanbebd0972011-06-15 05:25:01 +0000463#ifdef CONFIG_NET_POLL_CONTROLLER
464static void tun_poll_controller(struct net_device *dev)
465{
466 /*
467 * Tun only receives frames when:
468 * 1) the char device endpoint gets data from user space
469 * 2) the tun socket gets a sendmsg call from user space
470 * Since both of those are syncronous operations, we are guaranteed
471 * never to have pending data when we poll for it
472 * so theres nothing to do here but return.
473 * We need this though so netpoll recognizes us as an interface that
474 * supports polling, which enables bridge devices in virt setups to
475 * still use netconsole
476 */
477 return;
478}
479#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800480static const struct net_device_ops tun_netdev_ops = {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000481 .ndo_uninit = tun_net_uninit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800482 .ndo_open = tun_net_open,
483 .ndo_stop = tun_net_close,
Stephen Hemminger00829822008-11-20 20:14:53 -0800484 .ndo_start_xmit = tun_net_xmit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800485 .ndo_change_mtu = tun_net_change_mtu,
Michał Mirosław88255372011-04-19 06:13:10 +0000486 .ndo_fix_features = tun_net_fix_features,
Neil Hormanbebd0972011-06-15 05:25:01 +0000487#ifdef CONFIG_NET_POLL_CONTROLLER
488 .ndo_poll_controller = tun_poll_controller,
489#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800490};
491
492static const struct net_device_ops tap_netdev_ops = {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000493 .ndo_uninit = tun_net_uninit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800494 .ndo_open = tun_net_open,
495 .ndo_stop = tun_net_close,
Stephen Hemminger00829822008-11-20 20:14:53 -0800496 .ndo_start_xmit = tun_net_xmit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800497 .ndo_change_mtu = tun_net_change_mtu,
Michał Mirosław88255372011-04-19 06:13:10 +0000498 .ndo_fix_features = tun_net_fix_features,
Jiri Pirkoafc4b132011-08-16 06:29:01 +0000499 .ndo_set_rx_mode = tun_net_mclist,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800500 .ndo_set_mac_address = eth_mac_addr,
501 .ndo_validate_addr = eth_validate_addr,
Neil Hormanbebd0972011-06-15 05:25:01 +0000502#ifdef CONFIG_NET_POLL_CONTROLLER
503 .ndo_poll_controller = tun_poll_controller,
504#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800505};
506
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507/* Initialize net device. */
508static void tun_net_init(struct net_device *dev)
509{
510 struct tun_struct *tun = netdev_priv(dev);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400511
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 switch (tun->flags & TUN_TYPE_MASK) {
513 case TUN_TUN_DEV:
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800514 dev->netdev_ops = &tun_netdev_ops;
515
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 /* Point-to-Point TUN Device */
517 dev->hard_header_len = 0;
518 dev->addr_len = 0;
519 dev->mtu = 1500;
520
521 /* Zero header length */
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400522 dev->type = ARPHRD_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
524 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
525 break;
526
527 case TUN_TAP_DEV:
Kusanagi Kouichi7a0a9602008-12-29 18:23:28 -0800528 dev->netdev_ops = &tap_netdev_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 /* Ethernet TAP Device */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700530 ether_setup(dev);
Neil Horman550fd082011-07-26 06:05:38 +0000531 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532
Danny Kukawkaf2cedb62012-02-15 06:45:39 +0000533 eth_hw_addr_random(dev);
Brian Braunstein36226a82007-04-26 01:00:55 -0700534
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
536 break;
537 }
538}
539
540/* Character device part */
541
542/* Poll */
543static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400544{
Eric W. Biedermanb2430de2009-01-20 11:03:21 +0000545 struct tun_file *tfile = file->private_data;
546 struct tun_struct *tun = __tun_get(tfile);
Mariusz Kozlowski3c8a9c62009-07-05 19:48:35 +0000547 struct sock *sk;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800548 unsigned int mask = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549
550 if (!tun)
Eric W. Biedermaneac9e902009-01-20 10:59:05 +0000551 return POLLERR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000553 sk = tun->socket.sk;
Mariusz Kozlowski3c8a9c62009-07-05 19:48:35 +0000554
Joe Perches6b8a66e2011-03-02 07:18:10 +0000555 tun_debug(KERN_INFO, tun, "tun_chr_poll\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556
Eric Dumazet43815482010-04-29 11:01:49 +0000557 poll_wait(file, &tun->wq.wait, wait);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400558
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000559 if (!skb_queue_empty(&sk->sk_receive_queue))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 mask |= POLLIN | POLLRDNORM;
561
Herbert Xu33dccbb2009-02-05 21:25:32 -0800562 if (sock_writeable(sk) ||
563 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
564 sock_writeable(sk)))
565 mask |= POLLOUT | POLLWRNORM;
566
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000567 if (tun->dev->reg_state != NETREG_REGISTERED)
568 mask = POLLERR;
569
Eric W. Biederman631ab462009-01-20 11:00:40 +0000570 tun_put(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 return mask;
572}
573
Rusty Russellf42157c2008-08-15 15:15:10 -0700574/* prepad is the amount to reserve at front. len is length after that.
575 * linear is a hint as to how much to copy (usually headers). */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000576static struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
577 size_t prepad, size_t len,
578 size_t linear, int noblock)
Rusty Russellf42157c2008-08-15 15:15:10 -0700579{
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000580 struct sock *sk = tun->socket.sk;
Rusty Russellf42157c2008-08-15 15:15:10 -0700581 struct sk_buff *skb;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800582 int err;
Rusty Russellf42157c2008-08-15 15:15:10 -0700583
Herbert Xu82862742010-05-24 00:14:10 -0700584 sock_update_classid(sk);
585
Rusty Russellf42157c2008-08-15 15:15:10 -0700586 /* Under a page? Don't bother with paged skb. */
Herbert Xu0eca93b2009-04-14 02:09:43 -0700587 if (prepad + len < PAGE_SIZE || !linear)
Herbert Xu33dccbb2009-02-05 21:25:32 -0800588 linear = len;
Rusty Russellf42157c2008-08-15 15:15:10 -0700589
Herbert Xu33dccbb2009-02-05 21:25:32 -0800590 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
591 &err);
Rusty Russellf42157c2008-08-15 15:15:10 -0700592 if (!skb)
Herbert Xu33dccbb2009-02-05 21:25:32 -0800593 return ERR_PTR(err);
Rusty Russellf42157c2008-08-15 15:15:10 -0700594
595 skb_reserve(skb, prepad);
596 skb_put(skb, linear);
Herbert Xu33dccbb2009-02-05 21:25:32 -0800597 skb->data_len = len - linear;
598 skb->len += len - linear;
Rusty Russellf42157c2008-08-15 15:15:10 -0700599
600 return skb;
601}
602
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603/* Get packet from user space buffer */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000604static ssize_t tun_get_user(struct tun_struct *tun,
605 const struct iovec *iv, size_t count,
606 int noblock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607{
Harvey Harrison09640e62009-02-01 00:45:17 -0800608 struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609 struct sk_buff *skb;
stephen hemmingera504b862011-06-08 14:33:07 +0000610 size_t len = count, align = NET_SKB_PAD;
Rusty Russellf43798c2008-07-03 03:48:02 -0700611 struct virtio_net_hdr gso = { 0 };
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000612 int offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613
614 if (!(tun->flags & TUN_NO_PI)) {
615 if ((len -= sizeof(pi)) > count)
616 return -EINVAL;
617
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000618 if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 return -EFAULT;
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000620 offset += sizeof(pi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 }
622
Rusty Russellf43798c2008-07-03 03:48:02 -0700623 if (tun->flags & TUN_VNET_HDR) {
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200624 if ((len -= tun->vnet_hdr_sz) > count)
Rusty Russellf43798c2008-07-03 03:48:02 -0700625 return -EINVAL;
626
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000627 if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso)))
Rusty Russellf43798c2008-07-03 03:48:02 -0700628 return -EFAULT;
629
Herbert Xu49091222009-06-08 00:20:01 -0700630 if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
631 gso.csum_start + gso.csum_offset + 2 > gso.hdr_len)
632 gso.hdr_len = gso.csum_start + gso.csum_offset + 2;
633
Rusty Russellf43798c2008-07-03 03:48:02 -0700634 if (gso.hdr_len > len)
635 return -EINVAL;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200636 offset += tun->vnet_hdr_sz;
Rusty Russellf43798c2008-07-03 03:48:02 -0700637 }
638
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700639 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
stephen hemmingera504b862011-06-08 14:33:07 +0000640 align += NET_IP_ALIGN;
Herbert Xu0eca93b2009-04-14 02:09:43 -0700641 if (unlikely(len < ETH_HLEN ||
642 (gso.hdr_len && gso.hdr_len < ETH_HLEN)))
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700643 return -EINVAL;
644 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400645
Herbert Xu33dccbb2009-02-05 21:25:32 -0800646 skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock);
647 if (IS_ERR(skb)) {
648 if (PTR_ERR(skb) != -EAGAIN)
649 tun->dev->stats.rx_dropped++;
650 return PTR_ERR(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 }
652
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000653 if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) {
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700654 tun->dev->stats.rx_dropped++;
Dave Jones8f227572006-03-11 18:49:13 -0800655 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 return -EFAULT;
Dave Jones8f227572006-03-11 18:49:13 -0800657 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658
Rusty Russellf43798c2008-07-03 03:48:02 -0700659 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
660 if (!skb_partial_csum_set(skb, gso.csum_start,
661 gso.csum_offset)) {
662 tun->dev->stats.rx_frame_errors++;
663 kfree_skb(skb);
664 return -EINVAL;
665 }
Michał Mirosław88255372011-04-19 06:13:10 +0000666 }
Rusty Russellf43798c2008-07-03 03:48:02 -0700667
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 switch (tun->flags & TUN_TYPE_MASK) {
669 case TUN_TUN_DEV:
Ang Way Chuangf09f7ee2008-06-17 21:10:33 -0700670 if (tun->flags & TUN_NO_PI) {
671 switch (skb->data[0] & 0xf0) {
672 case 0x40:
673 pi.proto = htons(ETH_P_IP);
674 break;
675 case 0x60:
676 pi.proto = htons(ETH_P_IPV6);
677 break;
678 default:
679 tun->dev->stats.rx_dropped++;
680 kfree_skb(skb);
681 return -EINVAL;
682 }
683 }
684
Arnaldo Carvalho de Melo459a98e2007-03-19 15:30:44 -0700685 skb_reset_mac_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 skb->protocol = pi.proto;
Arnaldo Carvalho de Melo4c13eb62007-04-25 17:40:23 -0700687 skb->dev = tun->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 break;
689 case TUN_TAP_DEV:
690 skb->protocol = eth_type_trans(skb, tun->dev);
691 break;
Joe Perches6403eab2011-06-03 11:51:20 +0000692 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693
Rusty Russellf43798c2008-07-03 03:48:02 -0700694 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
695 pr_debug("GSO!\n");
696 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
697 case VIRTIO_NET_HDR_GSO_TCPV4:
698 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
699 break;
700 case VIRTIO_NET_HDR_GSO_TCPV6:
701 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
702 break;
Sridhar Samudralae36aa252009-07-14 14:21:04 +0000703 case VIRTIO_NET_HDR_GSO_UDP:
704 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
705 break;
Rusty Russellf43798c2008-07-03 03:48:02 -0700706 default:
707 tun->dev->stats.rx_frame_errors++;
708 kfree_skb(skb);
709 return -EINVAL;
710 }
711
712 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
713 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
714
715 skb_shinfo(skb)->gso_size = gso.gso_size;
716 if (skb_shinfo(skb)->gso_size == 0) {
717 tun->dev->stats.rx_frame_errors++;
718 kfree_skb(skb);
719 return -EINVAL;
720 }
721
722 /* Header must be checked, and gso_segs computed. */
723 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
724 skb_shinfo(skb)->gso_segs = 0;
725 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400726
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 netif_rx_ni(skb);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400728
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700729 tun->dev->stats.rx_packets++;
730 tun->dev->stats.rx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731
732 return count;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400733}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700735static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
736 unsigned long count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737{
Herbert Xu33dccbb2009-02-05 21:25:32 -0800738 struct file *file = iocb->ki_filp;
Herbert Xuab46d772009-02-14 20:46:39 -0800739 struct tun_struct *tun = tun_get(file);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000740 ssize_t result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741
742 if (!tun)
743 return -EBADFD;
744
Joe Perches6b8a66e2011-03-02 07:18:10 +0000745 tun_debug(KERN_INFO, tun, "tun_chr_write %ld\n", count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000747 result = tun_get_user(tun, iv, iov_length(iv, count),
Herbert Xu33dccbb2009-02-05 21:25:32 -0800748 file->f_flags & O_NONBLOCK);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000749
750 tun_put(tun);
751 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752}
753
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754/* Put packet to the user space buffer */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000755static ssize_t tun_put_user(struct tun_struct *tun,
756 struct sk_buff *skb,
757 const struct iovec *iv, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758{
759 struct tun_pi pi = { 0, skb->protocol };
760 ssize_t total = 0;
761
762 if (!(tun->flags & TUN_NO_PI)) {
763 if ((len -= sizeof(pi)) < 0)
764 return -EINVAL;
765
766 if (len < skb->len) {
767 /* Packet will be striped */
768 pi.flags |= TUN_PKT_STRIP;
769 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400770
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000771 if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772 return -EFAULT;
773 total += sizeof(pi);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400774 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775
Rusty Russellf43798c2008-07-03 03:48:02 -0700776 if (tun->flags & TUN_VNET_HDR) {
777 struct virtio_net_hdr gso = { 0 }; /* no info leak */
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200778 if ((len -= tun->vnet_hdr_sz) < 0)
Rusty Russellf43798c2008-07-03 03:48:02 -0700779 return -EINVAL;
780
781 if (skb_is_gso(skb)) {
782 struct skb_shared_info *sinfo = skb_shinfo(skb);
783
784 /* This is a hint as to how much should be linear. */
785 gso.hdr_len = skb_headlen(skb);
786 gso.gso_size = sinfo->gso_size;
787 if (sinfo->gso_type & SKB_GSO_TCPV4)
788 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
789 else if (sinfo->gso_type & SKB_GSO_TCPV6)
790 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
Sridhar Samudralae36aa252009-07-14 14:21:04 +0000791 else if (sinfo->gso_type & SKB_GSO_UDP)
792 gso.gso_type = VIRTIO_NET_HDR_GSO_UDP;
Michael S. Tsirkinef3db4a2010-07-21 04:32:45 +0000793 else {
Joe Perches6b8a66e2011-03-02 07:18:10 +0000794 pr_err("unexpected GSO type: "
Michael S. Tsirkinef3db4a2010-07-21 04:32:45 +0000795 "0x%x, gso_size %d, hdr_len %d\n",
796 sinfo->gso_type, gso.gso_size,
797 gso.hdr_len);
798 print_hex_dump(KERN_ERR, "tun: ",
799 DUMP_PREFIX_NONE,
800 16, 1, skb->head,
801 min((int)gso.hdr_len, 64), true);
802 WARN_ON_ONCE(1);
803 return -EINVAL;
804 }
Rusty Russellf43798c2008-07-03 03:48:02 -0700805 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
806 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
807 } else
808 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
809
810 if (skb->ip_summed == CHECKSUM_PARTIAL) {
811 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
Michał Mirosław55508d62010-12-14 15:24:08 +0000812 gso.csum_start = skb_checksum_start_offset(skb);
Rusty Russellf43798c2008-07-03 03:48:02 -0700813 gso.csum_offset = skb->csum_offset;
Jason Wang10a8d942011-06-10 00:56:17 +0000814 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
815 gso.flags = VIRTIO_NET_HDR_F_DATA_VALID;
Rusty Russellf43798c2008-07-03 03:48:02 -0700816 } /* else everything is zero */
817
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000818 if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
819 sizeof(gso))))
Rusty Russellf43798c2008-07-03 03:48:02 -0700820 return -EFAULT;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200821 total += tun->vnet_hdr_sz;
Rusty Russellf43798c2008-07-03 03:48:02 -0700822 }
823
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824 len = min_t(int, skb->len, len);
825
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000826 skb_copy_datagram_const_iovec(skb, 0, iv, total, len);
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000827 total += skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700829 tun->dev->stats.tx_packets++;
830 tun->dev->stats.tx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831
832 return total;
833}
834
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000835static ssize_t tun_do_read(struct tun_struct *tun,
836 struct kiocb *iocb, const struct iovec *iv,
837 ssize_t len, int noblock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 DECLARE_WAITQUEUE(wait, current);
840 struct sk_buff *skb;
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000841 ssize_t ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842
Joe Perches6b8a66e2011-03-02 07:18:10 +0000843 tun_debug(KERN_INFO, tun, "tun_chr_read\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844
Amos Kong61a5ff12011-06-09 00:27:10 -0700845 if (unlikely(!noblock))
846 add_wait_queue(&tun->wq.wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 while (len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 current->state = TASK_INTERRUPTIBLE;
849
850 /* Read frames from the queue */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000851 if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) {
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000852 if (noblock) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853 ret = -EAGAIN;
854 break;
855 }
856 if (signal_pending(current)) {
857 ret = -ERESTARTSYS;
858 break;
859 }
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000860 if (tun->dev->reg_state != NETREG_REGISTERED) {
861 ret = -EIO;
862 break;
863 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864
865 /* Nothing to read, let's sleep */
866 schedule();
867 continue;
868 }
869 netif_wake_queue(tun->dev);
870
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000871 ret = tun_put_user(tun, skb, iv, len);
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -0700872 kfree_skb(skb);
873 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 }
875
876 current->state = TASK_RUNNING;
Amos Kong61a5ff12011-06-09 00:27:10 -0700877 if (unlikely(!noblock))
878 remove_wait_queue(&tun->wq.wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000880 return ret;
881}
882
883static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
884 unsigned long count, loff_t pos)
885{
886 struct file *file = iocb->ki_filp;
887 struct tun_file *tfile = file->private_data;
888 struct tun_struct *tun = __tun_get(tfile);
889 ssize_t len, ret;
890
891 if (!tun)
892 return -EBADFD;
893 len = iov_length(iv, count);
894 if (len < 0) {
895 ret = -EINVAL;
896 goto out;
897 }
898
899 ret = tun_do_read(tun, iocb, iv, len, file->f_flags & O_NONBLOCK);
900 ret = min_t(ssize_t, ret, len);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000901out:
902 tun_put(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903 return ret;
904}
905
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906static void tun_setup(struct net_device *dev)
907{
908 struct tun_struct *tun = netdev_priv(dev);
909
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910 tun->owner = -1;
Guido Guenther8c644622007-07-02 22:50:25 -0700911 tun->group = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913 dev->ethtool_ops = &tun_ethtool_ops;
Herbert Xu9c3fea62009-04-18 14:15:52 +0000914 dev->destructor = tun_free_netdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915}
916
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -0800917/* Trivial set of netlink ops to allow deleting tun or tap
918 * device with netlink.
919 */
920static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
921{
922 return -EINVAL;
923}
924
925static struct rtnl_link_ops tun_link_ops __read_mostly = {
926 .kind = DRV_NAME,
927 .priv_size = sizeof(struct tun_struct),
928 .setup = tun_setup,
929 .validate = tun_validate,
930};
931
Herbert Xu33dccbb2009-02-05 21:25:32 -0800932static void tun_sock_write_space(struct sock *sk)
933{
934 struct tun_struct *tun;
Eric Dumazet43815482010-04-29 11:01:49 +0000935 wait_queue_head_t *wqueue;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800936
937 if (!sock_writeable(sk))
938 return;
939
Herbert Xu33dccbb2009-02-05 21:25:32 -0800940 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
941 return;
942
Eric Dumazet43815482010-04-29 11:01:49 +0000943 wqueue = sk_sleep(sk);
944 if (wqueue && waitqueue_active(wqueue))
945 wake_up_interruptible_sync_poll(wqueue, POLLOUT |
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000946 POLLWRNORM | POLLWRBAND);
Herbert Xuc722c622009-06-03 21:45:55 -0700947
Vitaliy Gusev80924e52009-12-25 07:17:43 +0000948 tun = tun_sk(sk)->tun;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800949 kill_fasync(&tun->fasync, SIGIO, POLL_OUT);
950}
951
952static void tun_sock_destruct(struct sock *sk)
953{
Vitaliy Gusev80924e52009-12-25 07:17:43 +0000954 free_netdev(tun_sk(sk)->tun->dev);
Herbert Xu33dccbb2009-02-05 21:25:32 -0800955}
956
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000957static int tun_sendmsg(struct kiocb *iocb, struct socket *sock,
958 struct msghdr *m, size_t total_len)
959{
960 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
961 return tun_get_user(tun, m->msg_iov, total_len,
962 m->msg_flags & MSG_DONTWAIT);
963}
964
965static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
966 struct msghdr *m, size_t total_len,
967 int flags)
968{
969 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
970 int ret;
971 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
972 return -EINVAL;
973 ret = tun_do_read(tun, iocb, m->msg_iov, total_len,
974 flags & MSG_DONTWAIT);
975 if (ret > total_len) {
976 m->msg_flags |= MSG_TRUNC;
977 ret = flags & MSG_TRUNC ? ret : total_len;
978 }
979 return ret;
980}
981
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000982static int tun_release(struct socket *sock)
983{
984 if (sock->sk)
985 sock_put(sock->sk);
986 return 0;
987}
988
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000989/* Ops structure to mimic raw sockets with tun */
990static const struct proto_ops tun_socket_ops = {
991 .sendmsg = tun_sendmsg,
992 .recvmsg = tun_recvmsg,
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000993 .release = tun_release,
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000994};
995
Herbert Xu33dccbb2009-02-05 21:25:32 -0800996static struct proto tun_proto = {
997 .name = "tun",
998 .owner = THIS_MODULE,
999 .obj_size = sizeof(struct tun_sock),
1000};
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001001
David Woodhouse980c9e82009-05-09 22:54:21 -07001002static int tun_flags(struct tun_struct *tun)
1003{
1004 int flags = 0;
1005
1006 if (tun->flags & TUN_TUN_DEV)
1007 flags |= IFF_TUN;
1008 else
1009 flags |= IFF_TAP;
1010
1011 if (tun->flags & TUN_NO_PI)
1012 flags |= IFF_NO_PI;
1013
1014 if (tun->flags & TUN_ONE_QUEUE)
1015 flags |= IFF_ONE_QUEUE;
1016
1017 if (tun->flags & TUN_VNET_HDR)
1018 flags |= IFF_VNET_HDR;
1019
1020 return flags;
1021}
1022
1023static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr,
1024 char *buf)
1025{
1026 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1027 return sprintf(buf, "0x%x\n", tun_flags(tun));
1028}
1029
1030static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr,
1031 char *buf)
1032{
1033 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1034 return sprintf(buf, "%d\n", tun->owner);
1035}
1036
1037static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
1038 char *buf)
1039{
1040 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1041 return sprintf(buf, "%d\n", tun->group);
1042}
1043
1044static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
1045static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL);
1046static DEVICE_ATTR(group, 0444, tun_show_group, NULL);
1047
Pavel Emelyanovd647a592008-04-16 00:41:16 -07001048static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049{
Herbert Xu33dccbb2009-02-05 21:25:32 -08001050 struct sock *sk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 struct tun_struct *tun;
1052 struct net_device *dev;
1053 int err;
1054
Eric W. Biederman74a3e5a2009-01-20 10:56:20 +00001055 dev = __dev_get_by_name(net, ifr->ifr_name);
1056 if (dev) {
Paul Moore2b980db2009-08-28 18:12:43 -04001057 const struct cred *cred = current_cred();
1058
David Woodhousef85ba782009-04-27 03:23:54 -07001059 if (ifr->ifr_flags & IFF_TUN_EXCL)
1060 return -EBUSY;
Eric W. Biederman74a3e5a2009-01-20 10:56:20 +00001061 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
1062 tun = netdev_priv(dev);
1063 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
1064 tun = netdev_priv(dev);
1065 else
1066 return -EINVAL;
1067
Paul Moore2b980db2009-08-28 18:12:43 -04001068 if (((tun->owner != -1 && cred->euid != tun->owner) ||
1069 (tun->group != -1 && !in_egroup_p(tun->group))) &&
1070 !capable(CAP_NET_ADMIN))
1071 return -EPERM;
Linus Torvaldsd7e96602009-09-14 10:37:28 -07001072 err = security_tun_dev_attach(tun->socket.sk);
Paul Moore2b980db2009-08-28 18:12:43 -04001073 if (err < 0)
1074 return err;
1075
Eric W. Biedermana7385ba2009-01-20 10:57:48 +00001076 err = tun_attach(tun, file);
1077 if (err < 0)
1078 return err;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001079 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080 else {
1081 char *name;
1082 unsigned long flags = 0;
1083
David Woodhouseca6bb5d2006-06-22 16:07:52 -07001084 if (!capable(CAP_NET_ADMIN))
1085 return -EPERM;
Paul Moore2b980db2009-08-28 18:12:43 -04001086 err = security_tun_dev_create();
1087 if (err < 0)
1088 return err;
David Woodhouseca6bb5d2006-06-22 16:07:52 -07001089
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090 /* Set dev type */
1091 if (ifr->ifr_flags & IFF_TUN) {
1092 /* TUN device */
1093 flags |= TUN_TUN_DEV;
1094 name = "tun%d";
1095 } else if (ifr->ifr_flags & IFF_TAP) {
1096 /* TAP device */
1097 flags |= TUN_TAP_DEV;
1098 name = "tap%d";
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001099 } else
Kusanagi Kouichi36989b92009-09-16 21:36:13 +00001100 return -EINVAL;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001101
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102 if (*ifr->ifr_name)
1103 name = ifr->ifr_name;
1104
1105 dev = alloc_netdev(sizeof(struct tun_struct), name,
1106 tun_setup);
1107 if (!dev)
1108 return -ENOMEM;
1109
Pavel Emelyanovfc54c652008-04-16 00:41:53 -07001110 dev_net_set(dev, net);
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001111 dev->rtnl_link_ops = &tun_link_ops;
Stephen Hemminger758e43b2008-11-19 22:10:37 -08001112
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 tun = netdev_priv(dev);
1114 tun->dev = dev;
1115 tun->flags = flags;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001116 tun->txflt.count = 0;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001117 tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118
Herbert Xu33dccbb2009-02-05 21:25:32 -08001119 err = -ENOMEM;
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001120 sk = sk_alloc(&init_net, AF_UNSPEC, GFP_KERNEL, &tun_proto);
Herbert Xu33dccbb2009-02-05 21:25:32 -08001121 if (!sk)
1122 goto err_free_dev;
1123
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001124 sk_change_net(sk, net);
Eric Dumazet43815482010-04-29 11:01:49 +00001125 tun->socket.wq = &tun->wq;
1126 init_waitqueue_head(&tun->wq.wait);
Michael S. Tsirkin05c28282010-01-14 06:17:09 +00001127 tun->socket.ops = &tun_socket_ops;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001128 sock_init_data(&tun->socket, sk);
1129 sk->sk_write_space = tun_sock_write_space;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001130 sk->sk_sndbuf = INT_MAX;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001131
Vitaliy Gusev80924e52009-12-25 07:17:43 +00001132 tun_sk(sk)->tun = tun;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001133
Paul Moore2b980db2009-08-28 18:12:43 -04001134 security_tun_dev_post_create(sk);
1135
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136 tun_net_init(dev);
1137
Michał Mirosław88255372011-04-19 06:13:10 +00001138 dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST |
1139 TUN_USER_FEATURES;
1140 dev->features = dev->hw_features;
1141
Linus Torvalds1da177e2005-04-16 15:20:36 -07001142 err = register_netdevice(tun->dev);
1143 if (err < 0)
Herbert Xu9c3fea62009-04-18 14:15:52 +00001144 goto err_free_sk;
1145
David Woodhouse980c9e82009-05-09 22:54:21 -07001146 if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) ||
1147 device_create_file(&tun->dev->dev, &dev_attr_owner) ||
1148 device_create_file(&tun->dev->dev, &dev_attr_group))
Joe Perches6b8a66e2011-03-02 07:18:10 +00001149 pr_err("Failed to create tun sysfs files\n");
David Woodhouse980c9e82009-05-09 22:54:21 -07001150
Herbert Xu9c3fea62009-04-18 14:15:52 +00001151 sk->sk_destruct = tun_sock_destruct;
Eric W. Biedermana7385ba2009-01-20 10:57:48 +00001152
1153 err = tun_attach(tun, file);
1154 if (err < 0)
Herbert Xu9c3fea62009-04-18 14:15:52 +00001155 goto failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001156 }
1157
Joe Perches6b8a66e2011-03-02 07:18:10 +00001158 tun_debug(KERN_INFO, tun, "tun_set_iff\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001159
1160 if (ifr->ifr_flags & IFF_NO_PI)
1161 tun->flags |= TUN_NO_PI;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -08001162 else
1163 tun->flags &= ~TUN_NO_PI;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001164
1165 if (ifr->ifr_flags & IFF_ONE_QUEUE)
1166 tun->flags |= TUN_ONE_QUEUE;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -08001167 else
1168 tun->flags &= ~TUN_ONE_QUEUE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169
Rusty Russellf43798c2008-07-03 03:48:02 -07001170 if (ifr->ifr_flags & IFF_VNET_HDR)
1171 tun->flags |= TUN_VNET_HDR;
1172 else
1173 tun->flags &= ~TUN_VNET_HDR;
1174
Max Krasnyanskye35259a2008-07-10 16:59:11 -07001175 /* Make sure persistent devices do not get stuck in
1176 * xoff state.
1177 */
1178 if (netif_running(tun->dev))
1179 netif_wake_queue(tun->dev);
1180
Linus Torvalds1da177e2005-04-16 15:20:36 -07001181 strcpy(ifr->ifr_name, tun->dev->name);
1182 return 0;
1183
Herbert Xu33dccbb2009-02-05 21:25:32 -08001184 err_free_sk:
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001185 tun_free_netdev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186 err_free_dev:
1187 free_netdev(dev);
1188 failed:
1189 return err;
1190}
1191
Herbert Xu876bfd42009-08-06 14:22:44 +00001192static int tun_get_iff(struct net *net, struct tun_struct *tun,
1193 struct ifreq *ifr)
Mark McLoughline3b99552008-08-15 15:09:56 -07001194{
Joe Perches6b8a66e2011-03-02 07:18:10 +00001195 tun_debug(KERN_INFO, tun, "tun_get_iff\n");
Mark McLoughline3b99552008-08-15 15:09:56 -07001196
1197 strcpy(ifr->ifr_name, tun->dev->name);
1198
David Woodhouse980c9e82009-05-09 22:54:21 -07001199 ifr->ifr_flags = tun_flags(tun);
Mark McLoughline3b99552008-08-15 15:09:56 -07001200
1201 return 0;
1202}
1203
Rusty Russell5228ddc2008-07-03 03:46:16 -07001204/* This is like a cut-down ethtool ops, except done via tun fd so no
1205 * privs required. */
Michał Mirosław88255372011-04-19 06:13:10 +00001206static int set_offload(struct tun_struct *tun, unsigned long arg)
Rusty Russell5228ddc2008-07-03 03:46:16 -07001207{
Michał Mirosławc8f44af2011-11-15 15:29:55 +00001208 netdev_features_t features = 0;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001209
1210 if (arg & TUN_F_CSUM) {
Michał Mirosław88255372011-04-19 06:13:10 +00001211 features |= NETIF_F_HW_CSUM;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001212 arg &= ~TUN_F_CSUM;
1213
1214 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
1215 if (arg & TUN_F_TSO_ECN) {
1216 features |= NETIF_F_TSO_ECN;
1217 arg &= ~TUN_F_TSO_ECN;
1218 }
1219 if (arg & TUN_F_TSO4)
1220 features |= NETIF_F_TSO;
1221 if (arg & TUN_F_TSO6)
1222 features |= NETIF_F_TSO6;
1223 arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
1224 }
Sridhar Samudralae36aa252009-07-14 14:21:04 +00001225
1226 if (arg & TUN_F_UFO) {
1227 features |= NETIF_F_UFO;
1228 arg &= ~TUN_F_UFO;
1229 }
Rusty Russell5228ddc2008-07-03 03:46:16 -07001230 }
1231
1232 /* This gives the user a way to test for new features in future by
1233 * trying to set them. */
1234 if (arg)
1235 return -EINVAL;
1236
Michał Mirosław88255372011-04-19 06:13:10 +00001237 tun->set_features = features;
1238 netdev_update_features(tun->dev);
Rusty Russell5228ddc2008-07-03 03:46:16 -07001239
1240 return 0;
1241}
1242
Arnd Bergmann50857e22009-11-06 22:52:32 -08001243static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
1244 unsigned long arg, int ifreq_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001245{
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001246 struct tun_file *tfile = file->private_data;
Eric W. Biederman631ab462009-01-20 11:00:40 +00001247 struct tun_struct *tun;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248 void __user* argp = (void __user*)arg;
Michael S. Tsirkin99405162010-02-14 01:01:10 +00001249 struct sock_fprog fprog;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250 struct ifreq ifr;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001251 int sndbuf;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001252 int vnet_hdr_sz;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001253 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254
1255 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
Arnd Bergmann50857e22009-11-06 22:52:32 -08001256 if (copy_from_user(&ifr, argp, ifreq_len))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257 return -EFAULT;
1258
Eric W. Biederman631ab462009-01-20 11:00:40 +00001259 if (cmd == TUNGETFEATURES) {
1260 /* Currently this just means: "what IFF flags are valid?".
1261 * This is needed because we never checked for invalid flags on
1262 * TUNSETIFF. */
1263 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
1264 IFF_VNET_HDR,
1265 (unsigned int __user*)argp);
1266 }
1267
Herbert Xu876bfd42009-08-06 14:22:44 +00001268 rtnl_lock();
1269
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001270 tun = __tun_get(tfile);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001271 if (cmd == TUNSETIFF && !tun) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001272 ifr.ifr_name[IFNAMSIZ-1] = '\0';
1273
Herbert Xu876bfd42009-08-06 14:22:44 +00001274 ret = tun_set_iff(tfile->net, file, &ifr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275
Herbert Xu876bfd42009-08-06 14:22:44 +00001276 if (ret)
1277 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001278
Arnd Bergmann50857e22009-11-06 22:52:32 -08001279 if (copy_to_user(argp, &ifr, ifreq_len))
Herbert Xu876bfd42009-08-06 14:22:44 +00001280 ret = -EFAULT;
1281 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001282 }
1283
Herbert Xu876bfd42009-08-06 14:22:44 +00001284 ret = -EBADFD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285 if (!tun)
Herbert Xu876bfd42009-08-06 14:22:44 +00001286 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001287
Joe Perches6b8a66e2011-03-02 07:18:10 +00001288 tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %d\n", cmd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289
Eric W. Biederman631ab462009-01-20 11:00:40 +00001290 ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291 switch (cmd) {
Mark McLoughline3b99552008-08-15 15:09:56 -07001292 case TUNGETIFF:
Herbert Xu876bfd42009-08-06 14:22:44 +00001293 ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
Mark McLoughline3b99552008-08-15 15:09:56 -07001294 if (ret)
Eric W. Biederman631ab462009-01-20 11:00:40 +00001295 break;
Mark McLoughline3b99552008-08-15 15:09:56 -07001296
Arnd Bergmann50857e22009-11-06 22:52:32 -08001297 if (copy_to_user(argp, &ifr, ifreq_len))
Eric W. Biederman631ab462009-01-20 11:00:40 +00001298 ret = -EFAULT;
Mark McLoughline3b99552008-08-15 15:09:56 -07001299 break;
1300
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301 case TUNSETNOCSUM:
1302 /* Disable/Enable checksum */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303
Michał Mirosław88255372011-04-19 06:13:10 +00001304 /* [unimplemented] */
1305 tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n",
Joe Perches6b8a66e2011-03-02 07:18:10 +00001306 arg ? "disabled" : "enabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001307 break;
1308
1309 case TUNSETPERSIST:
1310 /* Disable/Enable persist mode */
1311 if (arg)
1312 tun->flags |= TUN_PERSIST;
1313 else
1314 tun->flags &= ~TUN_PERSIST;
1315
Joe Perches6b8a66e2011-03-02 07:18:10 +00001316 tun_debug(KERN_INFO, tun, "persist %s\n",
1317 arg ? "enabled" : "disabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318 break;
1319
1320 case TUNSETOWNER:
1321 /* Set owner of the device */
1322 tun->owner = (uid_t) arg;
1323
Joe Perches6b8a66e2011-03-02 07:18:10 +00001324 tun_debug(KERN_INFO, tun, "owner set to %d\n", tun->owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325 break;
1326
Guido Guenther8c644622007-07-02 22:50:25 -07001327 case TUNSETGROUP:
1328 /* Set group of the device */
1329 tun->group= (gid_t) arg;
1330
Joe Perches6b8a66e2011-03-02 07:18:10 +00001331 tun_debug(KERN_INFO, tun, "group set to %d\n", tun->group);
Guido Guenther8c644622007-07-02 22:50:25 -07001332 break;
1333
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001334 case TUNSETLINK:
1335 /* Only allow setting the type when the interface is down */
1336 if (tun->dev->flags & IFF_UP) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001337 tun_debug(KERN_INFO, tun,
1338 "Linktype set failed because interface is up\n");
David S. Miller48abfe02008-04-23 19:37:58 -07001339 ret = -EBUSY;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001340 } else {
1341 tun->dev->type = (int) arg;
Joe Perches6b8a66e2011-03-02 07:18:10 +00001342 tun_debug(KERN_INFO, tun, "linktype set to %d\n",
1343 tun->dev->type);
David S. Miller48abfe02008-04-23 19:37:58 -07001344 ret = 0;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001345 }
Eric W. Biederman631ab462009-01-20 11:00:40 +00001346 break;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001347
Linus Torvalds1da177e2005-04-16 15:20:36 -07001348#ifdef TUN_DEBUG
1349 case TUNSETDEBUG:
1350 tun->debug = arg;
1351 break;
1352#endif
Rusty Russell5228ddc2008-07-03 03:46:16 -07001353 case TUNSETOFFLOAD:
Michał Mirosław88255372011-04-19 06:13:10 +00001354 ret = set_offload(tun, arg);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001355 break;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001356
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001357 case TUNSETTXFILTER:
1358 /* Can be set only for TAPs */
Eric W. Biederman631ab462009-01-20 11:00:40 +00001359 ret = -EINVAL;
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001360 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
Eric W. Biederman631ab462009-01-20 11:00:40 +00001361 break;
Harvey Harrisonc0e5a8c2008-07-16 12:45:34 -07001362 ret = update_filter(&tun->txflt, (void __user *)arg);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001363 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364
1365 case SIOCGIFHWADDR:
Uwe Kleine-Königb5950762010-11-01 15:38:34 -04001366 /* Get hw address */
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001367 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1368 ifr.ifr_hwaddr.sa_family = tun->dev->type;
Arnd Bergmann50857e22009-11-06 22:52:32 -08001369 if (copy_to_user(argp, &ifr, ifreq_len))
Eric W. Biederman631ab462009-01-20 11:00:40 +00001370 ret = -EFAULT;
1371 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372
1373 case SIOCSIFHWADDR:
Max Krasnyanskyf271b2c2008-07-14 22:18:19 -07001374 /* Set hw address */
Joe Perches6b8a66e2011-03-02 07:18:10 +00001375 tun_debug(KERN_DEBUG, tun, "set hw address: %pM\n",
1376 ifr.ifr_hwaddr.sa_data);
Kim B. Heino40102372008-02-29 12:26:21 -08001377
Kim B. Heino40102372008-02-29 12:26:21 -08001378 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001379 break;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001380
1381 case TUNGETSNDBUF:
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001382 sndbuf = tun->socket.sk->sk_sndbuf;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001383 if (copy_to_user(argp, &sndbuf, sizeof(sndbuf)))
1384 ret = -EFAULT;
1385 break;
1386
1387 case TUNSETSNDBUF:
1388 if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) {
1389 ret = -EFAULT;
1390 break;
1391 }
1392
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001393 tun->socket.sk->sk_sndbuf = sndbuf;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001394 break;
1395
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001396 case TUNGETVNETHDRSZ:
1397 vnet_hdr_sz = tun->vnet_hdr_sz;
1398 if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz)))
1399 ret = -EFAULT;
1400 break;
1401
1402 case TUNSETVNETHDRSZ:
1403 if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) {
1404 ret = -EFAULT;
1405 break;
1406 }
1407 if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) {
1408 ret = -EINVAL;
1409 break;
1410 }
1411
1412 tun->vnet_hdr_sz = vnet_hdr_sz;
1413 break;
1414
Michael S. Tsirkin99405162010-02-14 01:01:10 +00001415 case TUNATTACHFILTER:
1416 /* Can be set only for TAPs */
1417 ret = -EINVAL;
1418 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1419 break;
1420 ret = -EFAULT;
1421 if (copy_from_user(&fprog, argp, sizeof(fprog)))
1422 break;
1423
1424 ret = sk_attach_filter(&fprog, tun->socket.sk);
1425 break;
1426
1427 case TUNDETACHFILTER:
1428 /* Can be set only for TAPs */
1429 ret = -EINVAL;
1430 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1431 break;
1432 ret = sk_detach_filter(tun->socket.sk);
1433 break;
1434
Linus Torvalds1da177e2005-04-16 15:20:36 -07001435 default:
Eric W. Biederman631ab462009-01-20 11:00:40 +00001436 ret = -EINVAL;
1437 break;
Joe Perchesee289b62010-05-17 22:47:34 -07001438 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001439
Herbert Xu876bfd42009-08-06 14:22:44 +00001440unlock:
1441 rtnl_unlock();
1442 if (tun)
1443 tun_put(tun);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001444 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445}
1446
Arnd Bergmann50857e22009-11-06 22:52:32 -08001447static long tun_chr_ioctl(struct file *file,
1448 unsigned int cmd, unsigned long arg)
1449{
1450 return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq));
1451}
1452
1453#ifdef CONFIG_COMPAT
1454static long tun_chr_compat_ioctl(struct file *file,
1455 unsigned int cmd, unsigned long arg)
1456{
1457 switch (cmd) {
1458 case TUNSETIFF:
1459 case TUNGETIFF:
1460 case TUNSETTXFILTER:
1461 case TUNGETSNDBUF:
1462 case TUNSETSNDBUF:
1463 case SIOCGIFHWADDR:
1464 case SIOCSIFHWADDR:
1465 arg = (unsigned long)compat_ptr(arg);
1466 break;
1467 default:
1468 arg = (compat_ulong_t)arg;
1469 break;
1470 }
1471
1472 /*
1473 * compat_ifreq is shorter than ifreq, so we must not access beyond
1474 * the end of that structure. All fields that are used in this
1475 * driver are compatible though, we don't need to convert the
1476 * contents.
1477 */
1478 return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq));
1479}
1480#endif /* CONFIG_COMPAT */
1481
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482static int tun_chr_fasync(int fd, struct file *file, int on)
1483{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001484 struct tun_struct *tun = tun_get(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001485 int ret;
1486
1487 if (!tun)
1488 return -EBADFD;
1489
Joe Perches6b8a66e2011-03-02 07:18:10 +00001490 tun_debug(KERN_INFO, tun, "tun_chr_fasync %d\n", on);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491
1492 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
Jonathan Corbet9d319522008-06-19 15:50:37 -06001493 goto out;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001494
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 if (on) {
Eric W. Biederman609d7fa2006-10-02 02:17:15 -07001496 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497 if (ret)
Jonathan Corbet9d319522008-06-19 15:50:37 -06001498 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001499 tun->flags |= TUN_FASYNC;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001500 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -07001501 tun->flags &= ~TUN_FASYNC;
Jonathan Corbet9d319522008-06-19 15:50:37 -06001502 ret = 0;
1503out:
Eric W. Biederman631ab462009-01-20 11:00:40 +00001504 tun_put(tun);
Jonathan Corbet9d319522008-06-19 15:50:37 -06001505 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001506}
1507
1508static int tun_chr_open(struct inode *inode, struct file * file)
1509{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001510 struct tun_file *tfile;
Thomas Gleixnerdeed49f2009-10-14 01:19:46 -07001511
Joe Perches6b8a66e2011-03-02 07:18:10 +00001512 DBG1(KERN_INFO, "tunX: tun_chr_open\n");
Eric W. Biederman631ab462009-01-20 11:00:40 +00001513
1514 tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
1515 if (!tfile)
1516 return -ENOMEM;
Eric W. Biedermanc70f1822009-01-20 11:07:17 +00001517 atomic_set(&tfile->count, 0);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001518 tfile->tun = NULL;
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001519 tfile->net = get_net(current->nsproxy->net_ns);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001520 file->private_data = tfile;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001521 return 0;
1522}
1523
1524static int tun_chr_close(struct inode *inode, struct file *file)
1525{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001526 struct tun_file *tfile = file->private_data;
Eric W. Biedermanf0a4d0e2009-06-08 00:44:31 -07001527 struct tun_struct *tun;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001528
Eric W. Biedermanf0a4d0e2009-06-08 00:44:31 -07001529 tun = __tun_get(tfile);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001530 if (tun) {
Herbert Xud23e4362009-07-02 23:03:55 +00001531 struct net_device *dev = tun->dev;
1532
Joe Perches6b8a66e2011-03-02 07:18:10 +00001533 tun_debug(KERN_INFO, tun, "tun_chr_close\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001534
Eric W. Biederman631ab462009-01-20 11:00:40 +00001535 __tun_detach(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001536
Daniel Mack3ad2f3f2010-02-03 08:01:28 +08001537 /* If desirable, unregister the netdevice. */
Herbert Xud23e4362009-07-02 23:03:55 +00001538 if (!(tun->flags & TUN_PERSIST)) {
1539 rtnl_lock();
1540 if (dev->reg_state == NETREG_REGISTERED)
1541 unregister_netdevice(dev);
1542 rtnl_unlock();
1543 }
Eric W. Biederman631ab462009-01-20 11:00:40 +00001544 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545
Herbert Xu9c3fea62009-04-18 14:15:52 +00001546 tun = tfile->tun;
1547 if (tun)
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001548 sock_put(tun->socket.sk);
Herbert Xu9c3fea62009-04-18 14:15:52 +00001549
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001550 put_net(tfile->net);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001551 kfree(tfile);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001552
1553 return 0;
1554}
1555
Arjan van de Vend54b1fd2007-02-12 00:55:34 -08001556static const struct file_operations tun_fops = {
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001557 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001558 .llseek = no_llseek,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -07001559 .read = do_sync_read,
1560 .aio_read = tun_chr_aio_read,
1561 .write = do_sync_write,
1562 .aio_write = tun_chr_aio_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001563 .poll = tun_chr_poll,
Arnd Bergmann50857e22009-11-06 22:52:32 -08001564 .unlocked_ioctl = tun_chr_ioctl,
1565#ifdef CONFIG_COMPAT
1566 .compat_ioctl = tun_chr_compat_ioctl,
1567#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001568 .open = tun_chr_open,
1569 .release = tun_chr_close,
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001570 .fasync = tun_chr_fasync
Linus Torvalds1da177e2005-04-16 15:20:36 -07001571};
1572
1573static struct miscdevice tun_miscdev = {
1574 .minor = TUN_MINOR,
1575 .name = "tun",
Kay Sieverse454cea2009-09-18 23:01:12 +02001576 .nodename = "net/tun",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001577 .fops = &tun_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578};
1579
1580/* ethtool interface */
1581
1582static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1583{
1584 cmd->supported = 0;
1585 cmd->advertising = 0;
David Decotigny70739492011-04-27 18:32:40 +00001586 ethtool_cmd_speed_set(cmd, SPEED_10);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587 cmd->duplex = DUPLEX_FULL;
1588 cmd->port = PORT_TP;
1589 cmd->phy_address = 0;
1590 cmd->transceiver = XCVR_INTERNAL;
1591 cmd->autoneg = AUTONEG_DISABLE;
1592 cmd->maxtxpkt = 0;
1593 cmd->maxrxpkt = 0;
1594 return 0;
1595}
1596
1597static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1598{
1599 struct tun_struct *tun = netdev_priv(dev);
1600
Rick Jones33a5ba12011-11-15 14:59:53 +00001601 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1602 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001603
1604 switch (tun->flags & TUN_TYPE_MASK) {
1605 case TUN_TUN_DEV:
Rick Jones33a5ba12011-11-15 14:59:53 +00001606 strlcpy(info->bus_info, "tun", sizeof(info->bus_info));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001607 break;
1608 case TUN_TAP_DEV:
Rick Jones33a5ba12011-11-15 14:59:53 +00001609 strlcpy(info->bus_info, "tap", sizeof(info->bus_info));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001610 break;
1611 }
1612}
1613
1614static u32 tun_get_msglevel(struct net_device *dev)
1615{
1616#ifdef TUN_DEBUG
1617 struct tun_struct *tun = netdev_priv(dev);
1618 return tun->debug;
1619#else
1620 return -EOPNOTSUPP;
1621#endif
1622}
1623
1624static void tun_set_msglevel(struct net_device *dev, u32 value)
1625{
1626#ifdef TUN_DEBUG
1627 struct tun_struct *tun = netdev_priv(dev);
1628 tun->debug = value;
1629#endif
1630}
1631
Jeff Garzik7282d492006-09-13 14:30:00 -04001632static const struct ethtool_ops tun_ethtool_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633 .get_settings = tun_get_settings,
1634 .get_drvinfo = tun_get_drvinfo,
1635 .get_msglevel = tun_get_msglevel,
1636 .set_msglevel = tun_set_msglevel,
Nolan Leakebee31362010-07-27 13:53:43 +00001637 .get_link = ethtool_op_get_link,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638};
1639
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001640
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641static int __init tun_init(void)
1642{
1643 int ret = 0;
1644
Joe Perches6b8a66e2011-03-02 07:18:10 +00001645 pr_info("%s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1646 pr_info("%s\n", DRV_COPYRIGHT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001647
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001648 ret = rtnl_link_register(&tun_link_ops);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001649 if (ret) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001650 pr_err("Can't register link_ops\n");
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001651 goto err_linkops;
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001652 }
1653
Linus Torvalds1da177e2005-04-16 15:20:36 -07001654 ret = misc_register(&tun_miscdev);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001655 if (ret) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001656 pr_err("Can't register misc device %d\n", TUN_MINOR);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001657 goto err_misc;
1658 }
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001659 return 0;
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001660err_misc:
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001661 rtnl_link_unregister(&tun_link_ops);
1662err_linkops:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001663 return ret;
1664}
1665
1666static void tun_cleanup(void)
1667{
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001668 misc_deregister(&tun_miscdev);
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001669 rtnl_link_unregister(&tun_link_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670}
1671
Michael S. Tsirkin05c28282010-01-14 06:17:09 +00001672/* Get an underlying socket object from tun file. Returns error unless file is
1673 * attached to a device. The returned object works like a packet socket, it
1674 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1675 * holding a reference to the file for as long as the socket is in use. */
1676struct socket *tun_get_socket(struct file *file)
1677{
1678 struct tun_struct *tun;
1679 if (file->f_op != &tun_fops)
1680 return ERR_PTR(-EINVAL);
1681 tun = tun_get(file);
1682 if (!tun)
1683 return ERR_PTR(-EBADFD);
1684 tun_put(tun);
1685 return &tun->socket;
1686}
1687EXPORT_SYMBOL_GPL(tun_get_socket);
1688
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689module_init(tun_init);
1690module_exit(tun_cleanup);
1691MODULE_DESCRIPTION(DRV_DESCRIPTION);
1692MODULE_AUTHOR(DRV_COPYRIGHT);
1693MODULE_LICENSE("GPL");
1694MODULE_ALIAS_MISCDEV(TUN_MINOR);
Kay Sievers578454f2010-05-20 18:07:20 +02001695MODULE_ALIAS("devname:net/tun");