blob: b95a7f44a6d8dff4c62db9bfd814ce7c65111881 [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>
Joe Perches344dc8e2012-07-12 19:33:09 +000025 * Use eth_random_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 Krasnyanskyf271b2cc2008-07-14 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 Krasnyanskyf271b2cc2008-07-14 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 Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700128 struct fasync_struct *fasync;
Rusty Russell14daa022008-04-12 18:48:58 -0700129
Max Krasnyanskyf271b2cc2008-07-14 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 Krasnyanskyf271b2cc2008-07-14 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 Krasnyanskyf271b2cc2008-07-14 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 Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700286 addr_hash_set(filter->mask, addr[n].u);
Alex Williamsoncfbf84f2009-02-08 17:49:17 -0800287 }
Max Krasnyanskyf271b2cc2008-07-14 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++)
Joe Perches2e42e472012-05-09 17:17:46 +0000316 if (ether_addr_equal(eh->h_dest, filter->addr[i]))
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700317 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
Mikulas Patockab09e7862012-07-19 06:13:36 +0000361 BUG_ON(!test_bit(SOCK_EXTERNALLY_ALLOCATED, &tun->socket.flags));
362
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000363 sk_release_kernel(tun->socket.sk);
Herbert Xu9c3fea62009-04-18 14:15:52 +0000364}
365
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366/* Net device open. */
367static int tun_net_open(struct net_device *dev)
368{
369 netif_start_queue(dev);
370 return 0;
371}
372
373/* Net device close. */
374static int tun_net_close(struct net_device *dev)
375{
376 netif_stop_queue(dev);
377 return 0;
378}
379
380/* Net device start xmit */
Stephen Hemminger424efe92009-08-31 19:50:51 +0000381static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382{
383 struct tun_struct *tun = netdev_priv(dev);
384
Joe Perches6b8a66e2011-03-02 07:18:10 +0000385 tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386
387 /* Drop packet if interface is not attached */
Eric W. Biederman631ab462009-01-20 11:00:40 +0000388 if (!tun->tfile)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 goto drop;
390
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700391 /* Drop if the filter does not like it.
392 * This is a noop if the filter is disabled.
393 * Filter can be enabled only for the TAP devices. */
394 if (!check_filter(&tun->txflt, skb))
395 goto drop;
396
Michael S. Tsirkin99405162010-02-14 01:01:10 +0000397 if (tun->socket.sk->sk_filter &&
398 sk_filter(tun->socket.sk, skb))
399 goto drop;
400
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000401 if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 if (!(tun->flags & TUN_ONE_QUEUE)) {
403 /* Normal queueing mode. */
404 /* Packet scheduler handles dropping of further packets. */
405 netif_stop_queue(dev);
406
407 /* We won't see all dropped packets individually, so overrun
408 * error is more appropriate. */
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700409 dev->stats.tx_fifo_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 } else {
411 /* Single queue mode.
412 * Driver handles dropping of all packets itself. */
413 goto drop;
414 }
415 }
416
Michael S. Tsirkin0110d6f2010-04-13 04:59:44 +0000417 /* Orphan the skb - required as we might hang on to it
418 * for indefinite time. */
Michael S. Tsirkin868eefe2012-07-20 09:23:14 +0000419 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
420 goto drop;
Michael S. Tsirkin0110d6f2010-04-13 04:59:44 +0000421 skb_orphan(skb);
422
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700423 /* Enqueue packet */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000424 skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425
426 /* Notify and wake up reader process */
427 if (tun->flags & TUN_FASYNC)
428 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
Eric Dumazet43815482010-04-29 11:01:49 +0000429 wake_up_interruptible_poll(&tun->wq.wait, POLLIN |
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000430 POLLRDNORM | POLLRDBAND);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000431 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432
433drop:
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700434 dev->stats.tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 kfree_skb(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000436 return NETDEV_TX_OK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437}
438
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700439static void tun_net_mclist(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440{
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700441 /*
442 * This callback is supposed to deal with mc filter in
443 * _rx_ path and has nothing to do with the _tx_ path.
444 * In rx path we always accept everything userspace gives us.
445 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446}
447
Ed Swierk4885a502007-09-16 12:21:38 -0700448#define MIN_MTU 68
449#define MAX_MTU 65535
450
451static int
452tun_net_change_mtu(struct net_device *dev, int new_mtu)
453{
454 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
455 return -EINVAL;
456 dev->mtu = new_mtu;
457 return 0;
458}
459
Michał Mirosławc8f44af2011-11-15 15:29:55 +0000460static netdev_features_t tun_net_fix_features(struct net_device *dev,
461 netdev_features_t features)
Michał Mirosław88255372011-04-19 06:13:10 +0000462{
463 struct tun_struct *tun = netdev_priv(dev);
464
465 return (features & tun->set_features) | (features & ~TUN_USER_FEATURES);
466}
Neil Hormanbebd0972011-06-15 05:25:01 +0000467#ifdef CONFIG_NET_POLL_CONTROLLER
468static void tun_poll_controller(struct net_device *dev)
469{
470 /*
471 * Tun only receives frames when:
472 * 1) the char device endpoint gets data from user space
473 * 2) the tun socket gets a sendmsg call from user space
474 * Since both of those are syncronous operations, we are guaranteed
475 * never to have pending data when we poll for it
476 * so theres nothing to do here but return.
477 * We need this though so netpoll recognizes us as an interface that
478 * supports polling, which enables bridge devices in virt setups to
479 * still use netconsole
480 */
481 return;
482}
483#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800484static const struct net_device_ops tun_netdev_ops = {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000485 .ndo_uninit = tun_net_uninit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800486 .ndo_open = tun_net_open,
487 .ndo_stop = tun_net_close,
Stephen Hemminger00829822008-11-20 20:14:53 -0800488 .ndo_start_xmit = tun_net_xmit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800489 .ndo_change_mtu = tun_net_change_mtu,
Michał Mirosław88255372011-04-19 06:13:10 +0000490 .ndo_fix_features = tun_net_fix_features,
Neil Hormanbebd0972011-06-15 05:25:01 +0000491#ifdef CONFIG_NET_POLL_CONTROLLER
492 .ndo_poll_controller = tun_poll_controller,
493#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800494};
495
496static const struct net_device_ops tap_netdev_ops = {
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000497 .ndo_uninit = tun_net_uninit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800498 .ndo_open = tun_net_open,
499 .ndo_stop = tun_net_close,
Stephen Hemminger00829822008-11-20 20:14:53 -0800500 .ndo_start_xmit = tun_net_xmit,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800501 .ndo_change_mtu = tun_net_change_mtu,
Michał Mirosław88255372011-04-19 06:13:10 +0000502 .ndo_fix_features = tun_net_fix_features,
Jiri Pirkoafc4b132011-08-16 06:29:01 +0000503 .ndo_set_rx_mode = tun_net_mclist,
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800504 .ndo_set_mac_address = eth_mac_addr,
505 .ndo_validate_addr = eth_validate_addr,
Neil Hormanbebd0972011-06-15 05:25:01 +0000506#ifdef CONFIG_NET_POLL_CONTROLLER
507 .ndo_poll_controller = tun_poll_controller,
508#endif
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800509};
510
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511/* Initialize net device. */
512static void tun_net_init(struct net_device *dev)
513{
514 struct tun_struct *tun = netdev_priv(dev);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400515
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 switch (tun->flags & TUN_TYPE_MASK) {
517 case TUN_TUN_DEV:
Stephen Hemminger758e43b2008-11-19 22:10:37 -0800518 dev->netdev_ops = &tun_netdev_ops;
519
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 /* Point-to-Point TUN Device */
521 dev->hard_header_len = 0;
522 dev->addr_len = 0;
523 dev->mtu = 1500;
524
525 /* Zero header length */
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400526 dev->type = ARPHRD_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
528 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
529 break;
530
531 case TUN_TAP_DEV:
Kusanagi Kouichi7a0a9602008-12-29 18:23:28 -0800532 dev->netdev_ops = &tap_netdev_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 /* Ethernet TAP Device */
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700534 ether_setup(dev);
Neil Horman550fd082011-07-26 06:05:38 +0000535 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536
Danny Kukawkaf2cedb62012-02-15 06:45:39 +0000537 eth_hw_addr_random(dev);
Brian Braunstein36226a82007-04-26 01:00:55 -0700538
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
540 break;
541 }
542}
543
544/* Character device part */
545
546/* Poll */
547static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400548{
Eric W. Biedermanb2430de2009-01-20 11:03:21 +0000549 struct tun_file *tfile = file->private_data;
550 struct tun_struct *tun = __tun_get(tfile);
Mariusz Kozlowski3c8a9c62009-07-05 19:48:35 +0000551 struct sock *sk;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800552 unsigned int mask = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553
554 if (!tun)
Eric W. Biedermaneac9e902009-01-20 10:59:05 +0000555 return POLLERR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000557 sk = tun->socket.sk;
Mariusz Kozlowski3c8a9c62009-07-05 19:48:35 +0000558
Joe Perches6b8a66e2011-03-02 07:18:10 +0000559 tun_debug(KERN_INFO, tun, "tun_chr_poll\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560
Eric Dumazet43815482010-04-29 11:01:49 +0000561 poll_wait(file, &tun->wq.wait, wait);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400562
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000563 if (!skb_queue_empty(&sk->sk_receive_queue))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 mask |= POLLIN | POLLRDNORM;
565
Herbert Xu33dccbb2009-02-05 21:25:32 -0800566 if (sock_writeable(sk) ||
567 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
568 sock_writeable(sk)))
569 mask |= POLLOUT | POLLWRNORM;
570
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000571 if (tun->dev->reg_state != NETREG_REGISTERED)
572 mask = POLLERR;
573
Eric W. Biederman631ab462009-01-20 11:00:40 +0000574 tun_put(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 return mask;
576}
577
Rusty Russellf42157c2008-08-15 15:15:10 -0700578/* prepad is the amount to reserve at front. len is length after that.
579 * linear is a hint as to how much to copy (usually headers). */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000580static struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
581 size_t prepad, size_t len,
582 size_t linear, int noblock)
Rusty Russellf42157c2008-08-15 15:15:10 -0700583{
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000584 struct sock *sk = tun->socket.sk;
Rusty Russellf42157c2008-08-15 15:15:10 -0700585 struct sk_buff *skb;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800586 int err;
Rusty Russellf42157c2008-08-15 15:15:10 -0700587
Herbert Xu82862742010-05-24 00:14:10 -0700588 sock_update_classid(sk);
589
Rusty Russellf42157c2008-08-15 15:15:10 -0700590 /* Under a page? Don't bother with paged skb. */
Herbert Xu0eca93b2009-04-14 02:09:43 -0700591 if (prepad + len < PAGE_SIZE || !linear)
Herbert Xu33dccbb2009-02-05 21:25:32 -0800592 linear = len;
Rusty Russellf42157c2008-08-15 15:15:10 -0700593
Herbert Xu33dccbb2009-02-05 21:25:32 -0800594 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
595 &err);
Rusty Russellf42157c2008-08-15 15:15:10 -0700596 if (!skb)
Herbert Xu33dccbb2009-02-05 21:25:32 -0800597 return ERR_PTR(err);
Rusty Russellf42157c2008-08-15 15:15:10 -0700598
599 skb_reserve(skb, prepad);
600 skb_put(skb, linear);
Herbert Xu33dccbb2009-02-05 21:25:32 -0800601 skb->data_len = len - linear;
602 skb->len += len - linear;
Rusty Russellf42157c2008-08-15 15:15:10 -0700603
604 return skb;
605}
606
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607/* Get packet from user space buffer */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000608static ssize_t tun_get_user(struct tun_struct *tun,
609 const struct iovec *iv, size_t count,
610 int noblock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611{
Harvey Harrison09640e62009-02-01 00:45:17 -0800612 struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 struct sk_buff *skb;
stephen hemmingera504b862011-06-08 14:33:07 +0000614 size_t len = count, align = NET_SKB_PAD;
Rusty Russellf43798c2008-07-03 03:48:02 -0700615 struct virtio_net_hdr gso = { 0 };
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000616 int offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617
618 if (!(tun->flags & TUN_NO_PI)) {
619 if ((len -= sizeof(pi)) > count)
620 return -EINVAL;
621
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000622 if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 return -EFAULT;
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000624 offset += sizeof(pi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 }
626
Rusty Russellf43798c2008-07-03 03:48:02 -0700627 if (tun->flags & TUN_VNET_HDR) {
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200628 if ((len -= tun->vnet_hdr_sz) > count)
Rusty Russellf43798c2008-07-03 03:48:02 -0700629 return -EINVAL;
630
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000631 if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso)))
Rusty Russellf43798c2008-07-03 03:48:02 -0700632 return -EFAULT;
633
Herbert Xu49091222009-06-08 00:20:01 -0700634 if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
635 gso.csum_start + gso.csum_offset + 2 > gso.hdr_len)
636 gso.hdr_len = gso.csum_start + gso.csum_offset + 2;
637
Rusty Russellf43798c2008-07-03 03:48:02 -0700638 if (gso.hdr_len > len)
639 return -EINVAL;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200640 offset += tun->vnet_hdr_sz;
Rusty Russellf43798c2008-07-03 03:48:02 -0700641 }
642
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700643 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
stephen hemmingera504b862011-06-08 14:33:07 +0000644 align += NET_IP_ALIGN;
Herbert Xu0eca93b2009-04-14 02:09:43 -0700645 if (unlikely(len < ETH_HLEN ||
646 (gso.hdr_len && gso.hdr_len < ETH_HLEN)))
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700647 return -EINVAL;
648 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400649
Herbert Xu33dccbb2009-02-05 21:25:32 -0800650 skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock);
651 if (IS_ERR(skb)) {
652 if (PTR_ERR(skb) != -EAGAIN)
653 tun->dev->stats.rx_dropped++;
654 return PTR_ERR(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655 }
656
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000657 if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) {
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700658 tun->dev->stats.rx_dropped++;
Dave Jones8f227572006-03-11 18:49:13 -0800659 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 return -EFAULT;
Dave Jones8f227572006-03-11 18:49:13 -0800661 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662
Rusty Russellf43798c2008-07-03 03:48:02 -0700663 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
664 if (!skb_partial_csum_set(skb, gso.csum_start,
665 gso.csum_offset)) {
666 tun->dev->stats.rx_frame_errors++;
667 kfree_skb(skb);
668 return -EINVAL;
669 }
Michał Mirosław88255372011-04-19 06:13:10 +0000670 }
Rusty Russellf43798c2008-07-03 03:48:02 -0700671
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672 switch (tun->flags & TUN_TYPE_MASK) {
673 case TUN_TUN_DEV:
Ang Way Chuangf09f7ee2008-06-17 21:10:33 -0700674 if (tun->flags & TUN_NO_PI) {
675 switch (skb->data[0] & 0xf0) {
676 case 0x40:
677 pi.proto = htons(ETH_P_IP);
678 break;
679 case 0x60:
680 pi.proto = htons(ETH_P_IPV6);
681 break;
682 default:
683 tun->dev->stats.rx_dropped++;
684 kfree_skb(skb);
685 return -EINVAL;
686 }
687 }
688
Arnaldo Carvalho de Melo459a98e2007-03-19 15:30:44 -0700689 skb_reset_mac_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 skb->protocol = pi.proto;
Arnaldo Carvalho de Melo4c13eb62007-04-25 17:40:23 -0700691 skb->dev = tun->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692 break;
693 case TUN_TAP_DEV:
694 skb->protocol = eth_type_trans(skb, tun->dev);
695 break;
Joe Perches6403eab2011-06-03 11:51:20 +0000696 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697
Rusty Russellf43798c2008-07-03 03:48:02 -0700698 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
699 pr_debug("GSO!\n");
700 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
701 case VIRTIO_NET_HDR_GSO_TCPV4:
702 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
703 break;
704 case VIRTIO_NET_HDR_GSO_TCPV6:
705 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
706 break;
Sridhar Samudralae36aa252009-07-14 14:21:04 +0000707 case VIRTIO_NET_HDR_GSO_UDP:
708 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
709 break;
Rusty Russellf43798c2008-07-03 03:48:02 -0700710 default:
711 tun->dev->stats.rx_frame_errors++;
712 kfree_skb(skb);
713 return -EINVAL;
714 }
715
716 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
717 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
718
719 skb_shinfo(skb)->gso_size = gso.gso_size;
720 if (skb_shinfo(skb)->gso_size == 0) {
721 tun->dev->stats.rx_frame_errors++;
722 kfree_skb(skb);
723 return -EINVAL;
724 }
725
726 /* Header must be checked, and gso_segs computed. */
727 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
728 skb_shinfo(skb)->gso_segs = 0;
729 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400730
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 netif_rx_ni(skb);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400732
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700733 tun->dev->stats.rx_packets++;
734 tun->dev->stats.rx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735
736 return count;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400737}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700739static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
740 unsigned long count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741{
Herbert Xu33dccbb2009-02-05 21:25:32 -0800742 struct file *file = iocb->ki_filp;
Herbert Xuab46d772009-02-14 20:46:39 -0800743 struct tun_struct *tun = tun_get(file);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000744 ssize_t result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745
746 if (!tun)
747 return -EBADFD;
748
Joe Perches6b8a66e2011-03-02 07:18:10 +0000749 tun_debug(KERN_INFO, tun, "tun_chr_write %ld\n", count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750
Michael S. Tsirkin6f26c9a2009-04-20 01:26:11 +0000751 result = tun_get_user(tun, iv, iov_length(iv, count),
Herbert Xu33dccbb2009-02-05 21:25:32 -0800752 file->f_flags & O_NONBLOCK);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000753
754 tun_put(tun);
755 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756}
757
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758/* Put packet to the user space buffer */
stephen hemminger6f7c1562011-06-08 14:33:08 +0000759static ssize_t tun_put_user(struct tun_struct *tun,
760 struct sk_buff *skb,
761 const struct iovec *iv, int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762{
763 struct tun_pi pi = { 0, skb->protocol };
764 ssize_t total = 0;
765
766 if (!(tun->flags & TUN_NO_PI)) {
767 if ((len -= sizeof(pi)) < 0)
768 return -EINVAL;
769
770 if (len < skb->len) {
771 /* Packet will be striped */
772 pi.flags |= TUN_PKT_STRIP;
773 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400774
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000775 if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 return -EFAULT;
777 total += sizeof(pi);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400778 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779
Rusty Russellf43798c2008-07-03 03:48:02 -0700780 if (tun->flags & TUN_VNET_HDR) {
781 struct virtio_net_hdr gso = { 0 }; /* no info leak */
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200782 if ((len -= tun->vnet_hdr_sz) < 0)
Rusty Russellf43798c2008-07-03 03:48:02 -0700783 return -EINVAL;
784
785 if (skb_is_gso(skb)) {
786 struct skb_shared_info *sinfo = skb_shinfo(skb);
787
788 /* This is a hint as to how much should be linear. */
789 gso.hdr_len = skb_headlen(skb);
790 gso.gso_size = sinfo->gso_size;
791 if (sinfo->gso_type & SKB_GSO_TCPV4)
792 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
793 else if (sinfo->gso_type & SKB_GSO_TCPV6)
794 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
Sridhar Samudralae36aa252009-07-14 14:21:04 +0000795 else if (sinfo->gso_type & SKB_GSO_UDP)
796 gso.gso_type = VIRTIO_NET_HDR_GSO_UDP;
Michael S. Tsirkinef3db4a2010-07-21 04:32:45 +0000797 else {
Joe Perches6b8a66e2011-03-02 07:18:10 +0000798 pr_err("unexpected GSO type: "
Michael S. Tsirkinef3db4a2010-07-21 04:32:45 +0000799 "0x%x, gso_size %d, hdr_len %d\n",
800 sinfo->gso_type, gso.gso_size,
801 gso.hdr_len);
802 print_hex_dump(KERN_ERR, "tun: ",
803 DUMP_PREFIX_NONE,
804 16, 1, skb->head,
805 min((int)gso.hdr_len, 64), true);
806 WARN_ON_ONCE(1);
807 return -EINVAL;
808 }
Rusty Russellf43798c2008-07-03 03:48:02 -0700809 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
810 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
811 } else
812 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
813
814 if (skb->ip_summed == CHECKSUM_PARTIAL) {
815 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
Michał Mirosław55508d62010-12-14 15:24:08 +0000816 gso.csum_start = skb_checksum_start_offset(skb);
Rusty Russellf43798c2008-07-03 03:48:02 -0700817 gso.csum_offset = skb->csum_offset;
Jason Wang10a8d942011-06-10 00:56:17 +0000818 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
819 gso.flags = VIRTIO_NET_HDR_F_DATA_VALID;
Rusty Russellf43798c2008-07-03 03:48:02 -0700820 } /* else everything is zero */
821
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000822 if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
823 sizeof(gso))))
Rusty Russellf43798c2008-07-03 03:48:02 -0700824 return -EFAULT;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +0200825 total += tun->vnet_hdr_sz;
Rusty Russellf43798c2008-07-03 03:48:02 -0700826 }
827
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 len = min_t(int, skb->len, len);
829
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000830 skb_copy_datagram_const_iovec(skb, 0, iv, total, len);
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000831 total += skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700833 tun->dev->stats.tx_packets++;
834 tun->dev->stats.tx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835
836 return total;
837}
838
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000839static ssize_t tun_do_read(struct tun_struct *tun,
840 struct kiocb *iocb, const struct iovec *iv,
841 ssize_t len, int noblock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843 DECLARE_WAITQUEUE(wait, current);
844 struct sk_buff *skb;
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000845 ssize_t ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846
Joe Perches6b8a66e2011-03-02 07:18:10 +0000847 tun_debug(KERN_INFO, tun, "tun_chr_read\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848
Amos Kong61a5ff12011-06-09 00:27:10 -0700849 if (unlikely(!noblock))
850 add_wait_queue(&tun->wq.wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 while (len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852 current->state = TASK_INTERRUPTIBLE;
853
854 /* Read frames from the queue */
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +0000855 if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) {
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000856 if (noblock) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 ret = -EAGAIN;
858 break;
859 }
860 if (signal_pending(current)) {
861 ret = -ERESTARTSYS;
862 break;
863 }
Eric W. Biedermanc70f1822009-01-20 11:07:17 +0000864 if (tun->dev->reg_state != NETREG_REGISTERED) {
865 ret = -EIO;
866 break;
867 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868
869 /* Nothing to read, let's sleep */
870 schedule();
871 continue;
872 }
873 netif_wake_queue(tun->dev);
874
Michael S. Tsirkin43b39dc2009-04-20 01:25:59 +0000875 ret = tun_put_user(tun, skb, iv, len);
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -0700876 kfree_skb(skb);
877 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878 }
879
880 current->state = TASK_RUNNING;
Amos Kong61a5ff12011-06-09 00:27:10 -0700881 if (unlikely(!noblock))
882 remove_wait_queue(&tun->wq.wait, &wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000884 return ret;
885}
886
887static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
888 unsigned long count, loff_t pos)
889{
890 struct file *file = iocb->ki_filp;
891 struct tun_file *tfile = file->private_data;
892 struct tun_struct *tun = __tun_get(tfile);
893 ssize_t len, ret;
894
895 if (!tun)
896 return -EBADFD;
897 len = iov_length(iv, count);
898 if (len < 0) {
899 ret = -EINVAL;
900 goto out;
901 }
902
903 ret = tun_do_read(tun, iocb, iv, len, file->f_flags & O_NONBLOCK);
904 ret = min_t(ssize_t, ret, len);
Eric W. Biederman631ab462009-01-20 11:00:40 +0000905out:
906 tun_put(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907 return ret;
908}
909
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910static void tun_setup(struct net_device *dev)
911{
912 struct tun_struct *tun = netdev_priv(dev);
913
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914 tun->owner = -1;
Guido Guenther8c644622007-07-02 22:50:25 -0700915 tun->group = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917 dev->ethtool_ops = &tun_ethtool_ops;
Herbert Xu9c3fea62009-04-18 14:15:52 +0000918 dev->destructor = tun_free_netdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919}
920
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -0800921/* Trivial set of netlink ops to allow deleting tun or tap
922 * device with netlink.
923 */
924static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
925{
926 return -EINVAL;
927}
928
929static struct rtnl_link_ops tun_link_ops __read_mostly = {
930 .kind = DRV_NAME,
931 .priv_size = sizeof(struct tun_struct),
932 .setup = tun_setup,
933 .validate = tun_validate,
934};
935
Herbert Xu33dccbb2009-02-05 21:25:32 -0800936static void tun_sock_write_space(struct sock *sk)
937{
938 struct tun_struct *tun;
Eric Dumazet43815482010-04-29 11:01:49 +0000939 wait_queue_head_t *wqueue;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800940
941 if (!sock_writeable(sk))
942 return;
943
Herbert Xu33dccbb2009-02-05 21:25:32 -0800944 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
945 return;
946
Eric Dumazet43815482010-04-29 11:01:49 +0000947 wqueue = sk_sleep(sk);
948 if (wqueue && waitqueue_active(wqueue))
949 wake_up_interruptible_sync_poll(wqueue, POLLOUT |
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000950 POLLWRNORM | POLLWRBAND);
Herbert Xuc722c622009-06-03 21:45:55 -0700951
Vitaliy Gusev80924e52009-12-25 07:17:43 +0000952 tun = tun_sk(sk)->tun;
Herbert Xu33dccbb2009-02-05 21:25:32 -0800953 kill_fasync(&tun->fasync, SIGIO, POLL_OUT);
954}
955
956static void tun_sock_destruct(struct sock *sk)
957{
Vitaliy Gusev80924e52009-12-25 07:17:43 +0000958 free_netdev(tun_sk(sk)->tun->dev);
Herbert Xu33dccbb2009-02-05 21:25:32 -0800959}
960
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000961static int tun_sendmsg(struct kiocb *iocb, struct socket *sock,
962 struct msghdr *m, size_t total_len)
963{
964 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
965 return tun_get_user(tun, m->msg_iov, total_len,
966 m->msg_flags & MSG_DONTWAIT);
967}
968
969static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
970 struct msghdr *m, size_t total_len,
971 int flags)
972{
973 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
974 int ret;
975 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
976 return -EINVAL;
977 ret = tun_do_read(tun, iocb, m->msg_iov, total_len,
978 flags & MSG_DONTWAIT);
979 if (ret > total_len) {
980 m->msg_flags |= MSG_TRUNC;
981 ret = flags & MSG_TRUNC ? ret : total_len;
982 }
983 return ret;
984}
985
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000986static int tun_release(struct socket *sock)
987{
988 if (sock->sk)
989 sock_put(sock->sk);
990 return 0;
991}
992
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000993/* Ops structure to mimic raw sockets with tun */
994static const struct proto_ops tun_socket_ops = {
995 .sendmsg = tun_sendmsg,
996 .recvmsg = tun_recvmsg,
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +0000997 .release = tun_release,
Michael S. Tsirkin05c28282010-01-14 06:17:09 +0000998};
999
Herbert Xu33dccbb2009-02-05 21:25:32 -08001000static struct proto tun_proto = {
1001 .name = "tun",
1002 .owner = THIS_MODULE,
1003 .obj_size = sizeof(struct tun_sock),
1004};
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001005
David Woodhouse980c9e82009-05-09 22:54:21 -07001006static int tun_flags(struct tun_struct *tun)
1007{
1008 int flags = 0;
1009
1010 if (tun->flags & TUN_TUN_DEV)
1011 flags |= IFF_TUN;
1012 else
1013 flags |= IFF_TAP;
1014
1015 if (tun->flags & TUN_NO_PI)
1016 flags |= IFF_NO_PI;
1017
1018 if (tun->flags & TUN_ONE_QUEUE)
1019 flags |= IFF_ONE_QUEUE;
1020
1021 if (tun->flags & TUN_VNET_HDR)
1022 flags |= IFF_VNET_HDR;
1023
1024 return flags;
1025}
1026
1027static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr,
1028 char *buf)
1029{
1030 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1031 return sprintf(buf, "0x%x\n", tun_flags(tun));
1032}
1033
1034static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr,
1035 char *buf)
1036{
1037 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1038 return sprintf(buf, "%d\n", tun->owner);
1039}
1040
1041static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
1042 char *buf)
1043{
1044 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
1045 return sprintf(buf, "%d\n", tun->group);
1046}
1047
1048static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
1049static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL);
1050static DEVICE_ATTR(group, 0444, tun_show_group, NULL);
1051
Pavel Emelyanovd647a592008-04-16 00:41:16 -07001052static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053{
Herbert Xu33dccbb2009-02-05 21:25:32 -08001054 struct sock *sk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055 struct tun_struct *tun;
1056 struct net_device *dev;
1057 int err;
1058
Eric W. Biederman74a3e5a2009-01-20 10:56:20 +00001059 dev = __dev_get_by_name(net, ifr->ifr_name);
1060 if (dev) {
Paul Moore2b980db2009-08-28 18:12:43 -04001061 const struct cred *cred = current_cred();
1062
David Woodhousef85ba782009-04-27 03:23:54 -07001063 if (ifr->ifr_flags & IFF_TUN_EXCL)
1064 return -EBUSY;
Eric W. Biederman74a3e5a2009-01-20 10:56:20 +00001065 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
1066 tun = netdev_priv(dev);
1067 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
1068 tun = netdev_priv(dev);
1069 else
1070 return -EINVAL;
1071
Paul Moore2b980db2009-08-28 18:12:43 -04001072 if (((tun->owner != -1 && cred->euid != tun->owner) ||
1073 (tun->group != -1 && !in_egroup_p(tun->group))) &&
1074 !capable(CAP_NET_ADMIN))
1075 return -EPERM;
Linus Torvaldsd7e96602009-09-14 10:37:28 -07001076 err = security_tun_dev_attach(tun->socket.sk);
Paul Moore2b980db2009-08-28 18:12:43 -04001077 if (err < 0)
1078 return err;
1079
Eric W. Biedermana7385ba2009-01-20 10:57:48 +00001080 err = tun_attach(tun, file);
1081 if (err < 0)
1082 return err;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001083 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084 else {
1085 char *name;
1086 unsigned long flags = 0;
1087
David Woodhouseca6bb5d2006-06-22 16:07:52 -07001088 if (!capable(CAP_NET_ADMIN))
1089 return -EPERM;
Paul Moore2b980db2009-08-28 18:12:43 -04001090 err = security_tun_dev_create();
1091 if (err < 0)
1092 return err;
David Woodhouseca6bb5d2006-06-22 16:07:52 -07001093
Linus Torvalds1da177e2005-04-16 15:20:36 -07001094 /* Set dev type */
1095 if (ifr->ifr_flags & IFF_TUN) {
1096 /* TUN device */
1097 flags |= TUN_TUN_DEV;
1098 name = "tun%d";
1099 } else if (ifr->ifr_flags & IFF_TAP) {
1100 /* TAP device */
1101 flags |= TUN_TAP_DEV;
1102 name = "tap%d";
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001103 } else
Kusanagi Kouichi36989b92009-09-16 21:36:13 +00001104 return -EINVAL;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001105
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106 if (*ifr->ifr_name)
1107 name = ifr->ifr_name;
1108
1109 dev = alloc_netdev(sizeof(struct tun_struct), name,
1110 tun_setup);
1111 if (!dev)
1112 return -ENOMEM;
1113
Pavel Emelyanovfc54c652008-04-16 00:41:53 -07001114 dev_net_set(dev, net);
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001115 dev->rtnl_link_ops = &tun_link_ops;
Stephen Hemminger758e43b2008-11-19 22:10:37 -08001116
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117 tun = netdev_priv(dev);
1118 tun->dev = dev;
1119 tun->flags = flags;
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -07001120 tun->txflt.count = 0;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001121 tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
Mikulas Patockab09e7862012-07-19 06:13:36 +00001122 set_bit(SOCK_EXTERNALLY_ALLOCATED, &tun->socket.flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001123
Herbert Xu33dccbb2009-02-05 21:25:32 -08001124 err = -ENOMEM;
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001125 sk = sk_alloc(&init_net, AF_UNSPEC, GFP_KERNEL, &tun_proto);
Herbert Xu33dccbb2009-02-05 21:25:32 -08001126 if (!sk)
1127 goto err_free_dev;
1128
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001129 sk_change_net(sk, net);
Eric Dumazet43815482010-04-29 11:01:49 +00001130 tun->socket.wq = &tun->wq;
1131 init_waitqueue_head(&tun->wq.wait);
Michael S. Tsirkin05c28282010-01-14 06:17:09 +00001132 tun->socket.ops = &tun_socket_ops;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001133 sock_init_data(&tun->socket, sk);
1134 sk->sk_write_space = tun_sock_write_space;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001135 sk->sk_sndbuf = INT_MAX;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001136
Vitaliy Gusev80924e52009-12-25 07:17:43 +00001137 tun_sk(sk)->tun = tun;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001138
Paul Moore2b980db2009-08-28 18:12:43 -04001139 security_tun_dev_post_create(sk);
1140
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141 tun_net_init(dev);
1142
Michał Mirosław88255372011-04-19 06:13:10 +00001143 dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST |
1144 TUN_USER_FEATURES;
1145 dev->features = dev->hw_features;
1146
Linus Torvalds1da177e2005-04-16 15:20:36 -07001147 err = register_netdevice(tun->dev);
1148 if (err < 0)
Herbert Xu9c3fea62009-04-18 14:15:52 +00001149 goto err_free_sk;
1150
David Woodhouse980c9e82009-05-09 22:54:21 -07001151 if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) ||
1152 device_create_file(&tun->dev->dev, &dev_attr_owner) ||
1153 device_create_file(&tun->dev->dev, &dev_attr_group))
Joe Perches6b8a66e2011-03-02 07:18:10 +00001154 pr_err("Failed to create tun sysfs files\n");
David Woodhouse980c9e82009-05-09 22:54:21 -07001155
Herbert Xu9c3fea62009-04-18 14:15:52 +00001156 sk->sk_destruct = tun_sock_destruct;
Eric W. Biedermana7385ba2009-01-20 10:57:48 +00001157
1158 err = tun_attach(tun, file);
1159 if (err < 0)
Herbert Xu9c3fea62009-04-18 14:15:52 +00001160 goto failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001161 }
1162
Joe Perches6b8a66e2011-03-02 07:18:10 +00001163 tun_debug(KERN_INFO, tun, "tun_set_iff\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001164
1165 if (ifr->ifr_flags & IFF_NO_PI)
1166 tun->flags |= TUN_NO_PI;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -08001167 else
1168 tun->flags &= ~TUN_NO_PI;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169
1170 if (ifr->ifr_flags & IFF_ONE_QUEUE)
1171 tun->flags |= TUN_ONE_QUEUE;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -08001172 else
1173 tun->flags &= ~TUN_ONE_QUEUE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174
Rusty Russellf43798c2008-07-03 03:48:02 -07001175 if (ifr->ifr_flags & IFF_VNET_HDR)
1176 tun->flags |= TUN_VNET_HDR;
1177 else
1178 tun->flags &= ~TUN_VNET_HDR;
1179
Max Krasnyanskye35259a2008-07-10 16:59:11 -07001180 /* Make sure persistent devices do not get stuck in
1181 * xoff state.
1182 */
1183 if (netif_running(tun->dev))
1184 netif_wake_queue(tun->dev);
1185
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186 strcpy(ifr->ifr_name, tun->dev->name);
1187 return 0;
1188
Herbert Xu33dccbb2009-02-05 21:25:32 -08001189 err_free_sk:
Stanislav Kinsbursky1ab5ecb2012-03-12 02:59:41 +00001190 tun_free_netdev(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 err_free_dev:
1192 free_netdev(dev);
1193 failed:
1194 return err;
1195}
1196
Herbert Xu876bfd42009-08-06 14:22:44 +00001197static int tun_get_iff(struct net *net, struct tun_struct *tun,
1198 struct ifreq *ifr)
Mark McLoughline3b99552008-08-15 15:09:56 -07001199{
Joe Perches6b8a66e2011-03-02 07:18:10 +00001200 tun_debug(KERN_INFO, tun, "tun_get_iff\n");
Mark McLoughline3b99552008-08-15 15:09:56 -07001201
1202 strcpy(ifr->ifr_name, tun->dev->name);
1203
David Woodhouse980c9e82009-05-09 22:54:21 -07001204 ifr->ifr_flags = tun_flags(tun);
Mark McLoughline3b99552008-08-15 15:09:56 -07001205
1206 return 0;
1207}
1208
Rusty Russell5228ddc2008-07-03 03:46:16 -07001209/* This is like a cut-down ethtool ops, except done via tun fd so no
1210 * privs required. */
Michał Mirosław88255372011-04-19 06:13:10 +00001211static int set_offload(struct tun_struct *tun, unsigned long arg)
Rusty Russell5228ddc2008-07-03 03:46:16 -07001212{
Michał Mirosławc8f44af2011-11-15 15:29:55 +00001213 netdev_features_t features = 0;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001214
1215 if (arg & TUN_F_CSUM) {
Michał Mirosław88255372011-04-19 06:13:10 +00001216 features |= NETIF_F_HW_CSUM;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001217 arg &= ~TUN_F_CSUM;
1218
1219 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
1220 if (arg & TUN_F_TSO_ECN) {
1221 features |= NETIF_F_TSO_ECN;
1222 arg &= ~TUN_F_TSO_ECN;
1223 }
1224 if (arg & TUN_F_TSO4)
1225 features |= NETIF_F_TSO;
1226 if (arg & TUN_F_TSO6)
1227 features |= NETIF_F_TSO6;
1228 arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
1229 }
Sridhar Samudralae36aa252009-07-14 14:21:04 +00001230
1231 if (arg & TUN_F_UFO) {
1232 features |= NETIF_F_UFO;
1233 arg &= ~TUN_F_UFO;
1234 }
Rusty Russell5228ddc2008-07-03 03:46:16 -07001235 }
1236
1237 /* This gives the user a way to test for new features in future by
1238 * trying to set them. */
1239 if (arg)
1240 return -EINVAL;
1241
Michał Mirosław88255372011-04-19 06:13:10 +00001242 tun->set_features = features;
1243 netdev_update_features(tun->dev);
Rusty Russell5228ddc2008-07-03 03:46:16 -07001244
1245 return 0;
1246}
1247
Arnd Bergmann50857e22009-11-06 22:52:32 -08001248static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
1249 unsigned long arg, int ifreq_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250{
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001251 struct tun_file *tfile = file->private_data;
Eric W. Biederman631ab462009-01-20 11:00:40 +00001252 struct tun_struct *tun;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001253 void __user* argp = (void __user*)arg;
Michael S. Tsirkin99405162010-02-14 01:01:10 +00001254 struct sock_fprog fprog;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001255 struct ifreq ifr;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001256 int sndbuf;
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001257 int vnet_hdr_sz;
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -07001258 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259
1260 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
Arnd Bergmann50857e22009-11-06 22:52:32 -08001261 if (copy_from_user(&ifr, argp, ifreq_len))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262 return -EFAULT;
1263
Eric W. Biederman631ab462009-01-20 11:00:40 +00001264 if (cmd == TUNGETFEATURES) {
1265 /* Currently this just means: "what IFF flags are valid?".
1266 * This is needed because we never checked for invalid flags on
1267 * TUNSETIFF. */
1268 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
1269 IFF_VNET_HDR,
1270 (unsigned int __user*)argp);
1271 }
1272
Herbert Xu876bfd42009-08-06 14:22:44 +00001273 rtnl_lock();
1274
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001275 tun = __tun_get(tfile);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001276 if (cmd == TUNSETIFF && !tun) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 ifr.ifr_name[IFNAMSIZ-1] = '\0';
1278
Herbert Xu876bfd42009-08-06 14:22:44 +00001279 ret = tun_set_iff(tfile->net, file, &ifr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280
Herbert Xu876bfd42009-08-06 14:22:44 +00001281 if (ret)
1282 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283
Arnd Bergmann50857e22009-11-06 22:52:32 -08001284 if (copy_to_user(argp, &ifr, ifreq_len))
Herbert Xu876bfd42009-08-06 14:22:44 +00001285 ret = -EFAULT;
1286 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001287 }
1288
Herbert Xu876bfd42009-08-06 14:22:44 +00001289 ret = -EBADFD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290 if (!tun)
Herbert Xu876bfd42009-08-06 14:22:44 +00001291 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292
Joe Perches6b8a66e2011-03-02 07:18:10 +00001293 tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %d\n", cmd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294
Eric W. Biederman631ab462009-01-20 11:00:40 +00001295 ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 switch (cmd) {
Mark McLoughline3b99552008-08-15 15:09:56 -07001297 case TUNGETIFF:
Herbert Xu876bfd42009-08-06 14:22:44 +00001298 ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
Mark McLoughline3b99552008-08-15 15:09:56 -07001299 if (ret)
Eric W. Biederman631ab462009-01-20 11:00:40 +00001300 break;
Mark McLoughline3b99552008-08-15 15:09:56 -07001301
Arnd Bergmann50857e22009-11-06 22:52:32 -08001302 if (copy_to_user(argp, &ifr, ifreq_len))
Eric W. Biederman631ab462009-01-20 11:00:40 +00001303 ret = -EFAULT;
Mark McLoughline3b99552008-08-15 15:09:56 -07001304 break;
1305
Linus Torvalds1da177e2005-04-16 15:20:36 -07001306 case TUNSETNOCSUM:
1307 /* Disable/Enable checksum */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308
Michał Mirosław88255372011-04-19 06:13:10 +00001309 /* [unimplemented] */
1310 tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n",
Joe Perches6b8a66e2011-03-02 07:18:10 +00001311 arg ? "disabled" : "enabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001312 break;
1313
1314 case TUNSETPERSIST:
1315 /* Disable/Enable persist mode */
1316 if (arg)
1317 tun->flags |= TUN_PERSIST;
1318 else
1319 tun->flags &= ~TUN_PERSIST;
1320
Joe Perches6b8a66e2011-03-02 07:18:10 +00001321 tun_debug(KERN_INFO, tun, "persist %s\n",
1322 arg ? "enabled" : "disabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 break;
1324
1325 case TUNSETOWNER:
1326 /* Set owner of the device */
1327 tun->owner = (uid_t) arg;
1328
Joe Perches6b8a66e2011-03-02 07:18:10 +00001329 tun_debug(KERN_INFO, tun, "owner set to %d\n", tun->owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001330 break;
1331
Guido Guenther8c644622007-07-02 22:50:25 -07001332 case TUNSETGROUP:
1333 /* Set group of the device */
1334 tun->group= (gid_t) arg;
1335
Joe Perches6b8a66e2011-03-02 07:18:10 +00001336 tun_debug(KERN_INFO, tun, "group set to %d\n", tun->group);
Guido Guenther8c644622007-07-02 22:50:25 -07001337 break;
1338
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001339 case TUNSETLINK:
1340 /* Only allow setting the type when the interface is down */
1341 if (tun->dev->flags & IFF_UP) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001342 tun_debug(KERN_INFO, tun,
1343 "Linktype set failed because interface is up\n");
David S. Miller48abfe02008-04-23 19:37:58 -07001344 ret = -EBUSY;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001345 } else {
1346 tun->dev->type = (int) arg;
Joe Perches6b8a66e2011-03-02 07:18:10 +00001347 tun_debug(KERN_INFO, tun, "linktype set to %d\n",
1348 tun->dev->type);
David S. Miller48abfe02008-04-23 19:37:58 -07001349 ret = 0;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001350 }
Eric W. Biederman631ab462009-01-20 11:00:40 +00001351 break;
Mike Kershawff4cc3a2005-09-01 17:40:05 -07001352
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353#ifdef TUN_DEBUG
1354 case TUNSETDEBUG:
1355 tun->debug = arg;
1356 break;
1357#endif
Rusty Russell5228ddc2008-07-03 03:46:16 -07001358 case TUNSETOFFLOAD:
Michał Mirosław88255372011-04-19 06:13:10 +00001359 ret = set_offload(tun, arg);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001360 break;
Rusty Russell5228ddc2008-07-03 03:46:16 -07001361
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -07001362 case TUNSETTXFILTER:
1363 /* Can be set only for TAPs */
Eric W. Biederman631ab462009-01-20 11:00:40 +00001364 ret = -EINVAL;
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -07001365 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
Eric W. Biederman631ab462009-01-20 11:00:40 +00001366 break;
Harvey Harrisonc0e5a8c2008-07-16 12:45:34 -07001367 ret = update_filter(&tun->txflt, (void __user *)arg);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001368 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369
1370 case SIOCGIFHWADDR:
Uwe Kleine-Königb5950762010-11-01 15:38:34 -04001371 /* Get hw address */
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -07001372 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1373 ifr.ifr_hwaddr.sa_family = tun->dev->type;
Arnd Bergmann50857e22009-11-06 22:52:32 -08001374 if (copy_to_user(argp, &ifr, ifreq_len))
Eric W. Biederman631ab462009-01-20 11:00:40 +00001375 ret = -EFAULT;
1376 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001377
1378 case SIOCSIFHWADDR:
Max Krasnyanskyf271b2cc2008-07-14 22:18:19 -07001379 /* Set hw address */
Joe Perches6b8a66e2011-03-02 07:18:10 +00001380 tun_debug(KERN_DEBUG, tun, "set hw address: %pM\n",
1381 ifr.ifr_hwaddr.sa_data);
Kim B. Heino40102372008-02-29 12:26:21 -08001382
Kim B. Heino40102372008-02-29 12:26:21 -08001383 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001384 break;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001385
1386 case TUNGETSNDBUF:
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001387 sndbuf = tun->socket.sk->sk_sndbuf;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001388 if (copy_to_user(argp, &sndbuf, sizeof(sndbuf)))
1389 ret = -EFAULT;
1390 break;
1391
1392 case TUNSETSNDBUF:
1393 if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) {
1394 ret = -EFAULT;
1395 break;
1396 }
1397
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001398 tun->socket.sk->sk_sndbuf = sndbuf;
Herbert Xu33dccbb2009-02-05 21:25:32 -08001399 break;
1400
Michael S. Tsirkind9d52b52010-03-17 17:45:01 +02001401 case TUNGETVNETHDRSZ:
1402 vnet_hdr_sz = tun->vnet_hdr_sz;
1403 if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz)))
1404 ret = -EFAULT;
1405 break;
1406
1407 case TUNSETVNETHDRSZ:
1408 if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) {
1409 ret = -EFAULT;
1410 break;
1411 }
1412 if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) {
1413 ret = -EINVAL;
1414 break;
1415 }
1416
1417 tun->vnet_hdr_sz = vnet_hdr_sz;
1418 break;
1419
Michael S. Tsirkin99405162010-02-14 01:01:10 +00001420 case TUNATTACHFILTER:
1421 /* Can be set only for TAPs */
1422 ret = -EINVAL;
1423 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1424 break;
1425 ret = -EFAULT;
1426 if (copy_from_user(&fprog, argp, sizeof(fprog)))
1427 break;
1428
1429 ret = sk_attach_filter(&fprog, tun->socket.sk);
1430 break;
1431
1432 case TUNDETACHFILTER:
1433 /* Can be set only for TAPs */
1434 ret = -EINVAL;
1435 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1436 break;
1437 ret = sk_detach_filter(tun->socket.sk);
1438 break;
1439
Linus Torvalds1da177e2005-04-16 15:20:36 -07001440 default:
Eric W. Biederman631ab462009-01-20 11:00:40 +00001441 ret = -EINVAL;
1442 break;
Joe Perchesee289b62010-05-17 22:47:34 -07001443 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001444
Herbert Xu876bfd42009-08-06 14:22:44 +00001445unlock:
1446 rtnl_unlock();
1447 if (tun)
1448 tun_put(tun);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001449 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001450}
1451
Arnd Bergmann50857e22009-11-06 22:52:32 -08001452static long tun_chr_ioctl(struct file *file,
1453 unsigned int cmd, unsigned long arg)
1454{
1455 return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq));
1456}
1457
1458#ifdef CONFIG_COMPAT
1459static long tun_chr_compat_ioctl(struct file *file,
1460 unsigned int cmd, unsigned long arg)
1461{
1462 switch (cmd) {
1463 case TUNSETIFF:
1464 case TUNGETIFF:
1465 case TUNSETTXFILTER:
1466 case TUNGETSNDBUF:
1467 case TUNSETSNDBUF:
1468 case SIOCGIFHWADDR:
1469 case SIOCSIFHWADDR:
1470 arg = (unsigned long)compat_ptr(arg);
1471 break;
1472 default:
1473 arg = (compat_ulong_t)arg;
1474 break;
1475 }
1476
1477 /*
1478 * compat_ifreq is shorter than ifreq, so we must not access beyond
1479 * the end of that structure. All fields that are used in this
1480 * driver are compatible though, we don't need to convert the
1481 * contents.
1482 */
1483 return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq));
1484}
1485#endif /* CONFIG_COMPAT */
1486
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487static int tun_chr_fasync(int fd, struct file *file, int on)
1488{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001489 struct tun_struct *tun = tun_get(file);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001490 int ret;
1491
1492 if (!tun)
1493 return -EBADFD;
1494
Joe Perches6b8a66e2011-03-02 07:18:10 +00001495 tun_debug(KERN_INFO, tun, "tun_chr_fasync %d\n", on);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496
1497 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
Jonathan Corbet9d319522008-06-19 15:50:37 -06001498 goto out;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001499
Linus Torvalds1da177e2005-04-16 15:20:36 -07001500 if (on) {
Eric W. Biederman609d7fa2006-10-02 02:17:15 -07001501 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001502 if (ret)
Jonathan Corbet9d319522008-06-19 15:50:37 -06001503 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504 tun->flags |= TUN_FASYNC;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001505 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -07001506 tun->flags &= ~TUN_FASYNC;
Jonathan Corbet9d319522008-06-19 15:50:37 -06001507 ret = 0;
1508out:
Eric W. Biederman631ab462009-01-20 11:00:40 +00001509 tun_put(tun);
Jonathan Corbet9d319522008-06-19 15:50:37 -06001510 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001511}
1512
1513static int tun_chr_open(struct inode *inode, struct file * file)
1514{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001515 struct tun_file *tfile;
Thomas Gleixnerdeed49f2009-10-14 01:19:46 -07001516
Joe Perches6b8a66e2011-03-02 07:18:10 +00001517 DBG1(KERN_INFO, "tunX: tun_chr_open\n");
Eric W. Biederman631ab462009-01-20 11:00:40 +00001518
1519 tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
1520 if (!tfile)
1521 return -ENOMEM;
Eric W. Biedermanc70f1822009-01-20 11:07:17 +00001522 atomic_set(&tfile->count, 0);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001523 tfile->tun = NULL;
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001524 tfile->net = get_net(current->nsproxy->net_ns);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001525 file->private_data = tfile;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001526 return 0;
1527}
1528
1529static int tun_chr_close(struct inode *inode, struct file *file)
1530{
Eric W. Biederman631ab462009-01-20 11:00:40 +00001531 struct tun_file *tfile = file->private_data;
Eric W. Biedermanf0a4d0e2009-06-08 00:44:31 -07001532 struct tun_struct *tun;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001533
Eric W. Biedermanf0a4d0e2009-06-08 00:44:31 -07001534 tun = __tun_get(tfile);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001535 if (tun) {
Herbert Xud23e4362009-07-02 23:03:55 +00001536 struct net_device *dev = tun->dev;
1537
Joe Perches6b8a66e2011-03-02 07:18:10 +00001538 tun_debug(KERN_INFO, tun, "tun_chr_close\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001539
Eric W. Biederman631ab462009-01-20 11:00:40 +00001540 __tun_detach(tun);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001541
Daniel Mack3ad2f3f2010-02-03 08:01:28 +08001542 /* If desirable, unregister the netdevice. */
Herbert Xud23e4362009-07-02 23:03:55 +00001543 if (!(tun->flags & TUN_PERSIST)) {
1544 rtnl_lock();
1545 if (dev->reg_state == NETREG_REGISTERED)
1546 unregister_netdevice(dev);
1547 rtnl_unlock();
1548 }
Eric W. Biederman631ab462009-01-20 11:00:40 +00001549 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001550
Herbert Xu9c3fea62009-04-18 14:15:52 +00001551 tun = tfile->tun;
1552 if (tun)
Michael S. Tsirkin89f56d12009-08-30 07:04:42 +00001553 sock_put(tun->socket.sk);
Herbert Xu9c3fea62009-04-18 14:15:52 +00001554
Eric W. Biederman36b50ba2009-01-20 11:01:48 +00001555 put_net(tfile->net);
Eric W. Biederman631ab462009-01-20 11:00:40 +00001556 kfree(tfile);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557
1558 return 0;
1559}
1560
Arjan van de Vend54b1fd2007-02-12 00:55:34 -08001561static const struct file_operations tun_fops = {
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001562 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001563 .llseek = no_llseek,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -07001564 .read = do_sync_read,
1565 .aio_read = tun_chr_aio_read,
1566 .write = do_sync_write,
1567 .aio_write = tun_chr_aio_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001568 .poll = tun_chr_poll,
Arnd Bergmann50857e22009-11-06 22:52:32 -08001569 .unlocked_ioctl = tun_chr_ioctl,
1570#ifdef CONFIG_COMPAT
1571 .compat_ioctl = tun_chr_compat_ioctl,
1572#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573 .open = tun_chr_open,
1574 .release = tun_chr_close,
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001575 .fasync = tun_chr_fasync
Linus Torvalds1da177e2005-04-16 15:20:36 -07001576};
1577
1578static struct miscdevice tun_miscdev = {
1579 .minor = TUN_MINOR,
1580 .name = "tun",
Kay Sieverse454cea2009-09-18 23:01:12 +02001581 .nodename = "net/tun",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001582 .fops = &tun_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001583};
1584
1585/* ethtool interface */
1586
1587static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1588{
1589 cmd->supported = 0;
1590 cmd->advertising = 0;
David Decotigny70739492011-04-27 18:32:40 +00001591 ethtool_cmd_speed_set(cmd, SPEED_10);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001592 cmd->duplex = DUPLEX_FULL;
1593 cmd->port = PORT_TP;
1594 cmd->phy_address = 0;
1595 cmd->transceiver = XCVR_INTERNAL;
1596 cmd->autoneg = AUTONEG_DISABLE;
1597 cmd->maxtxpkt = 0;
1598 cmd->maxrxpkt = 0;
1599 return 0;
1600}
1601
1602static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1603{
1604 struct tun_struct *tun = netdev_priv(dev);
1605
Rick Jones33a5ba12011-11-15 14:59:53 +00001606 strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1607 strlcpy(info->version, DRV_VERSION, sizeof(info->version));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608
1609 switch (tun->flags & TUN_TYPE_MASK) {
1610 case TUN_TUN_DEV:
Rick Jones33a5ba12011-11-15 14:59:53 +00001611 strlcpy(info->bus_info, "tun", sizeof(info->bus_info));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001612 break;
1613 case TUN_TAP_DEV:
Rick Jones33a5ba12011-11-15 14:59:53 +00001614 strlcpy(info->bus_info, "tap", sizeof(info->bus_info));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001615 break;
1616 }
1617}
1618
1619static u32 tun_get_msglevel(struct net_device *dev)
1620{
1621#ifdef TUN_DEBUG
1622 struct tun_struct *tun = netdev_priv(dev);
1623 return tun->debug;
1624#else
1625 return -EOPNOTSUPP;
1626#endif
1627}
1628
1629static void tun_set_msglevel(struct net_device *dev, u32 value)
1630{
1631#ifdef TUN_DEBUG
1632 struct tun_struct *tun = netdev_priv(dev);
1633 tun->debug = value;
1634#endif
1635}
1636
Jeff Garzik7282d492006-09-13 14:30:00 -04001637static const struct ethtool_ops tun_ethtool_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638 .get_settings = tun_get_settings,
1639 .get_drvinfo = tun_get_drvinfo,
1640 .get_msglevel = tun_get_msglevel,
1641 .set_msglevel = tun_set_msglevel,
Nolan Leakebee31362010-07-27 13:53:43 +00001642 .get_link = ethtool_op_get_link,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001643};
1644
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001645
Linus Torvalds1da177e2005-04-16 15:20:36 -07001646static int __init tun_init(void)
1647{
1648 int ret = 0;
1649
Joe Perches6b8a66e2011-03-02 07:18:10 +00001650 pr_info("%s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1651 pr_info("%s\n", DRV_COPYRIGHT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001652
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001653 ret = rtnl_link_register(&tun_link_ops);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001654 if (ret) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001655 pr_err("Can't register link_ops\n");
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001656 goto err_linkops;
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001657 }
1658
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659 ret = misc_register(&tun_miscdev);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001660 if (ret) {
Joe Perches6b8a66e2011-03-02 07:18:10 +00001661 pr_err("Can't register misc device %d\n", TUN_MINOR);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001662 goto err_misc;
1663 }
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001664 return 0;
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001665err_misc:
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001666 rtnl_link_unregister(&tun_link_ops);
1667err_linkops:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001668 return ret;
1669}
1670
1671static void tun_cleanup(void)
1672{
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001673 misc_deregister(&tun_miscdev);
Eric W. Biedermanf019a7a2009-01-21 16:02:16 -08001674 rtnl_link_unregister(&tun_link_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001675}
1676
Michael S. Tsirkin05c28282010-01-14 06:17:09 +00001677/* Get an underlying socket object from tun file. Returns error unless file is
1678 * attached to a device. The returned object works like a packet socket, it
1679 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1680 * holding a reference to the file for as long as the socket is in use. */
1681struct socket *tun_get_socket(struct file *file)
1682{
1683 struct tun_struct *tun;
1684 if (file->f_op != &tun_fops)
1685 return ERR_PTR(-EINVAL);
1686 tun = tun_get(file);
1687 if (!tun)
1688 return ERR_PTR(-EBADFD);
1689 tun_put(tun);
1690 return &tun->socket;
1691}
1692EXPORT_SYMBOL_GPL(tun_get_socket);
1693
Linus Torvalds1da177e2005-04-16 15:20:36 -07001694module_init(tun_init);
1695module_exit(tun_cleanup);
1696MODULE_DESCRIPTION(DRV_DESCRIPTION);
1697MODULE_AUTHOR(DRV_COPYRIGHT);
1698MODULE_LICENSE("GPL");
1699MODULE_ALIAS_MISCDEV(TUN_MINOR);
Kay Sievers578454f2010-05-20 18:07:20 +02001700MODULE_ALIAS("devname:net/tun");