blob: 0ce07a339c7eee77a209fc365e664976ed4a6b57 [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 *
Brian Braunstein36226a82007-04-26 01:00:55 -070021 * Brian Braunstein <linuxkernel@bristyle.com> 2007/03/23
22 * Fixed hw address handling. Now net_device.dev_addr is kept consistent
23 * with tun.dev_addr when the address is set by this module.
24 *
Mike Kershawff4cc3a2005-09-01 17:40:05 -070025 * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
26 * Add TUNSETLINK ioctl to set the link encapsulation
27 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 * Mark Smith <markzzzsmith@yahoo.com.au>
29 * Use random_ether_addr() for tap MAC address.
30 *
31 * Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20
32 * Fixes in packet dropping, queue length setting and queue wakeup.
33 * Increased default tx queue length.
34 * Added ethtool API.
35 * Minor cleanups
36 *
37 * Daniel Podlejski <underley@underley.eu.org>
38 * Modifications for 2.3.99-pre5 kernel.
39 */
40
41#define DRV_NAME "tun"
42#define DRV_VERSION "1.6"
43#define DRV_DESCRIPTION "Universal TUN/TAP device driver"
44#define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
45
Linus Torvalds1da177e2005-04-16 15:20:36 -070046#include <linux/module.h>
47#include <linux/errno.h>
48#include <linux/kernel.h>
49#include <linux/major.h>
50#include <linux/slab.h>
51#include <linux/poll.h>
52#include <linux/fcntl.h>
53#include <linux/init.h>
54#include <linux/skbuff.h>
55#include <linux/netdevice.h>
56#include <linux/etherdevice.h>
57#include <linux/miscdevice.h>
58#include <linux/ethtool.h>
59#include <linux/rtnetlink.h>
60#include <linux/if.h>
61#include <linux/if_arp.h>
62#include <linux/if_ether.h>
63#include <linux/if_tun.h>
64#include <linux/crc32.h>
Pavel Emelyanovd647a592008-04-16 00:41:16 -070065#include <linux/nsproxy.h>
Eric W. Biederman881d9662007-09-17 11:56:21 -070066#include <net/net_namespace.h>
Pavel Emelyanov79d17602008-04-16 00:40:46 -070067#include <net/netns/generic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69#include <asm/system.h>
70#include <asm/uaccess.h>
71
Rusty Russell14daa022008-04-12 18:48:58 -070072/* Uncomment to enable debugging */
73/* #define TUN_DEBUG 1 */
74
Linus Torvalds1da177e2005-04-16 15:20:36 -070075#ifdef TUN_DEBUG
76static int debug;
Rusty Russell14daa022008-04-12 18:48:58 -070077
78#define DBG if(tun->debug)printk
79#define DBG1 if(debug==2)printk
80#else
81#define DBG( a... )
82#define DBG1( a... )
Linus Torvalds1da177e2005-04-16 15:20:36 -070083#endif
84
Rusty Russell14daa022008-04-12 18:48:58 -070085struct tun_struct {
86 struct list_head list;
87 unsigned long flags;
88 int attached;
89 uid_t owner;
90 gid_t group;
91
92 wait_queue_head_t read_wait;
93 struct sk_buff_head readq;
94
95 struct net_device *dev;
96
97 struct fasync_struct *fasync;
98
99 unsigned long if_flags;
100 u8 dev_addr[ETH_ALEN];
101 u32 chr_filter[2];
102 u32 net_filter[2];
103
104#ifdef TUN_DEBUG
105 int debug;
106#endif
107};
108
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109/* Network device part of the driver */
110
Pavel Emelyanov79d17602008-04-16 00:40:46 -0700111static unsigned int tun_net_id;
112struct tun_net {
113 struct list_head dev_list;
114};
115
Jeff Garzik7282d492006-09-13 14:30:00 -0400116static const struct ethtool_ops tun_ethtool_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117
118/* Net device open. */
119static int tun_net_open(struct net_device *dev)
120{
121 netif_start_queue(dev);
122 return 0;
123}
124
125/* Net device close. */
126static int tun_net_close(struct net_device *dev)
127{
128 netif_stop_queue(dev);
129 return 0;
130}
131
132/* Net device start xmit */
133static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
134{
135 struct tun_struct *tun = netdev_priv(dev);
136
137 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
138
139 /* Drop packet if interface is not attached */
140 if (!tun->attached)
141 goto drop;
142
143 /* Packet dropping */
144 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
145 if (!(tun->flags & TUN_ONE_QUEUE)) {
146 /* Normal queueing mode. */
147 /* Packet scheduler handles dropping of further packets. */
148 netif_stop_queue(dev);
149
150 /* We won't see all dropped packets individually, so overrun
151 * error is more appropriate. */
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700152 dev->stats.tx_fifo_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 } else {
154 /* Single queue mode.
155 * Driver handles dropping of all packets itself. */
156 goto drop;
157 }
158 }
159
160 /* Queue packet */
161 skb_queue_tail(&tun->readq, skb);
162 dev->trans_start = jiffies;
163
164 /* Notify and wake up reader process */
165 if (tun->flags & TUN_FASYNC)
166 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
167 wake_up_interruptible(&tun->read_wait);
168 return 0;
169
170drop:
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700171 dev->stats.tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 kfree_skb(skb);
173 return 0;
174}
175
176/** Add the specified Ethernet address to this multicast filter. */
177static void
178add_multi(u32* filter, const u8* addr)
179{
180 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
181 filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
182}
183
184/** Remove the specified Ethernet addres from this multicast filter. */
185static void
186del_multi(u32* filter, const u8* addr)
187{
188 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
189 filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31));
190}
191
192/** Update the list of multicast groups to which the network device belongs.
193 * This list is used to filter packets being sent from the character device to
194 * the network device. */
195static void
196tun_net_mclist(struct net_device *dev)
197{
198 struct tun_struct *tun = netdev_priv(dev);
199 const struct dev_mc_list *mclist;
200 int i;
Joe Perches0795af52007-10-03 17:59:30 -0700201 DECLARE_MAC_BUF(mac);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n",
203 dev->name, dev->mc_count);
204 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
205 for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL;
206 i++, mclist = mclist->next) {
207 add_multi(tun->net_filter, mclist->dmi_addr);
Joe Perches0795af52007-10-03 17:59:30 -0700208 DBG(KERN_DEBUG "%s: tun_net_mclist: %s\n",
209 dev->name, print_mac(mac, mclist->dmi_addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 }
211}
212
Ed Swierk4885a502007-09-16 12:21:38 -0700213#define MIN_MTU 68
214#define MAX_MTU 65535
215
216static int
217tun_net_change_mtu(struct net_device *dev, int new_mtu)
218{
219 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
220 return -EINVAL;
221 dev->mtu = new_mtu;
222 return 0;
223}
224
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225/* Initialize net device. */
226static void tun_net_init(struct net_device *dev)
227{
228 struct tun_struct *tun = netdev_priv(dev);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400229
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 switch (tun->flags & TUN_TYPE_MASK) {
231 case TUN_TUN_DEV:
232 /* Point-to-Point TUN Device */
233 dev->hard_header_len = 0;
234 dev->addr_len = 0;
235 dev->mtu = 1500;
Ed Swierk4885a502007-09-16 12:21:38 -0700236 dev->change_mtu = tun_net_change_mtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237
238 /* Zero header length */
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400239 dev->type = ARPHRD_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
241 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
242 break;
243
244 case TUN_TAP_DEV:
245 /* Ethernet TAP Device */
246 dev->set_multicast_list = tun_net_mclist;
247
248 ether_setup(dev);
Ed Swierk4885a502007-09-16 12:21:38 -0700249 dev->change_mtu = tun_net_change_mtu;
Brian Braunstein36226a82007-04-26 01:00:55 -0700250
251 /* random address already created for us by tun_set_iff, use it */
252 memcpy(dev->dev_addr, tun->dev_addr, min(sizeof(tun->dev_addr), sizeof(dev->dev_addr)) );
253
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
255 break;
256 }
257}
258
259/* Character device part */
260
261/* Poll */
262static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400263{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 struct tun_struct *tun = file->private_data;
265 unsigned int mask = POLLOUT | POLLWRNORM;
266
267 if (!tun)
268 return -EBADFD;
269
270 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
271
272 poll_wait(file, &tun->read_wait, wait);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400273
David S. Millerb03efcf2005-07-08 14:57:23 -0700274 if (!skb_queue_empty(&tun->readq))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 mask |= POLLIN | POLLRDNORM;
276
277 return mask;
278}
279
280/* Get packet from user space buffer */
281static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
282{
283 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
284 struct sk_buff *skb;
285 size_t len = count, align = 0;
286
287 if (!(tun->flags & TUN_NO_PI)) {
288 if ((len -= sizeof(pi)) > count)
289 return -EINVAL;
290
291 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
292 return -EFAULT;
293 }
294
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700295 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 align = NET_IP_ALIGN;
Rusty Russelle01bf1c2008-04-12 18:49:30 -0700297 if (unlikely(len < ETH_HLEN))
298 return -EINVAL;
299 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400300
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700302 tun->dev->stats.rx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 return -ENOMEM;
304 }
305
306 if (align)
307 skb_reserve(skb, align);
Dave Jones8f227572006-03-11 18:49:13 -0800308 if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700309 tun->dev->stats.rx_dropped++;
Dave Jones8f227572006-03-11 18:49:13 -0800310 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 return -EFAULT;
Dave Jones8f227572006-03-11 18:49:13 -0800312 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 switch (tun->flags & TUN_TYPE_MASK) {
315 case TUN_TUN_DEV:
Arnaldo Carvalho de Melo459a98e2007-03-19 15:30:44 -0700316 skb_reset_mac_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 skb->protocol = pi.proto;
Arnaldo Carvalho de Melo4c13eb62007-04-25 17:40:23 -0700318 skb->dev = tun->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 break;
320 case TUN_TAP_DEV:
321 skb->protocol = eth_type_trans(skb, tun->dev);
322 break;
323 };
324
325 if (tun->flags & TUN_NOCHECKSUM)
326 skb->ip_summed = CHECKSUM_UNNECESSARY;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400327
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 netif_rx_ni(skb);
329 tun->dev->last_rx = jiffies;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400330
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700331 tun->dev->stats.rx_packets++;
332 tun->dev->stats.rx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333
334 return count;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400335}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700337static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
338 unsigned long count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339{
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700340 struct tun_struct *tun = iocb->ki_filp->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341
342 if (!tun)
343 return -EBADFD;
344
345 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
346
Akinobu Mita52427c92007-11-19 22:46:51 -0800347 return tun_get_user(tun, (struct iovec *) iv, iov_length(iv, count));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348}
349
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350/* Put packet to the user space buffer */
351static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
352 struct sk_buff *skb,
353 struct iovec *iv, int len)
354{
355 struct tun_pi pi = { 0, skb->protocol };
356 ssize_t total = 0;
357
358 if (!(tun->flags & TUN_NO_PI)) {
359 if ((len -= sizeof(pi)) < 0)
360 return -EINVAL;
361
362 if (len < skb->len) {
363 /* Packet will be striped */
364 pi.flags |= TUN_PKT_STRIP;
365 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400366
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
368 return -EFAULT;
369 total += sizeof(pi);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400370 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371
372 len = min_t(int, skb->len, len);
373
374 skb_copy_datagram_iovec(skb, 0, iv, len);
375 total += len;
376
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700377 tun->dev->stats.tx_packets++;
378 tun->dev->stats.tx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379
380 return total;
381}
382
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700383static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
384 unsigned long count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385{
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700386 struct file *file = iocb->ki_filp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 struct tun_struct *tun = file->private_data;
388 DECLARE_WAITQUEUE(wait, current);
389 struct sk_buff *skb;
390 ssize_t len, ret = 0;
Joe Perches0795af52007-10-03 17:59:30 -0700391 DECLARE_MAC_BUF(mac);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
393 if (!tun)
394 return -EBADFD;
395
396 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
397
Akinobu Mita52427c92007-11-19 22:46:51 -0800398 len = iov_length(iv, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 if (len < 0)
400 return -EINVAL;
401
402 add_wait_queue(&tun->read_wait, &wait);
403 while (len) {
404 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
405 u8 addr[ ETH_ALEN];
406 int bit_nr;
407
408 current->state = TASK_INTERRUPTIBLE;
409
410 /* Read frames from the queue */
411 if (!(skb=skb_dequeue(&tun->readq))) {
412 if (file->f_flags & O_NONBLOCK) {
413 ret = -EAGAIN;
414 break;
415 }
416 if (signal_pending(current)) {
417 ret = -ERESTARTSYS;
418 break;
419 }
420
421 /* Nothing to read, let's sleep */
422 schedule();
423 continue;
424 }
425 netif_wake_queue(tun->dev);
426
427 /** Decide whether to accept this packet. This code is designed to
428 * behave identically to an Ethernet interface. Accept the packet if
429 * - we are promiscuous.
430 * - the packet is addressed to us.
431 * - the packet is broadcast.
432 * - the packet is multicast and
433 * - we are multicast promiscous.
434 * - we belong to the multicast group.
435 */
Arnaldo Carvalho de Melod626f622007-03-27 18:55:52 -0300436 skb_copy_from_linear_data(skb, addr, min_t(size_t, sizeof addr,
437 skb->len));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 bit_nr = ether_crc(sizeof addr, addr) >> 26;
439 if ((tun->if_flags & IFF_PROMISC) ||
440 memcmp(addr, tun->dev_addr, sizeof addr) == 0 ||
441 memcmp(addr, ones, sizeof addr) == 0 ||
442 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) ||
443 (addr[0] == 0x33 && addr[1] == 0x33)) &&
444 ((tun->if_flags & IFF_ALLMULTI) ||
445 (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) {
Joe Perches0795af52007-10-03 17:59:30 -0700446 DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %s\n",
447 tun->dev->name, print_mac(mac, addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
449 kfree_skb(skb);
450 break;
451 } else {
Joe Perches0795af52007-10-03 17:59:30 -0700452 DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %s\n",
453 tun->dev->name, print_mac(mac, addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 kfree_skb(skb);
455 continue;
456 }
457 }
458
459 current->state = TASK_RUNNING;
460 remove_wait_queue(&tun->read_wait, &wait);
461
462 return ret;
463}
464
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465static void tun_setup(struct net_device *dev)
466{
467 struct tun_struct *tun = netdev_priv(dev);
468
469 skb_queue_head_init(&tun->readq);
470 init_waitqueue_head(&tun->read_wait);
471
472 tun->owner = -1;
Guido Guenther8c644622007-07-02 22:50:25 -0700473 tun->group = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 dev->open = tun_net_open;
476 dev->hard_start_xmit = tun_net_xmit;
477 dev->stop = tun_net_close;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 dev->ethtool_ops = &tun_ethtool_ops;
479 dev->destructor = free_netdev;
Pavel Emelyanovfc54c652008-04-16 00:41:53 -0700480 dev->features |= NETIF_F_NETNS_LOCAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481}
482
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700483static struct tun_struct *tun_get_by_name(struct tun_net *tn, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484{
485 struct tun_struct *tun;
486
487 ASSERT_RTNL();
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700488 list_for_each_entry(tun, &tn->dev_list, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
490 return tun;
491 }
492
493 return NULL;
494}
495
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700496static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497{
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700498 struct tun_net *tn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 struct tun_struct *tun;
500 struct net_device *dev;
501 int err;
502
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700503 tn = net_generic(net, tun_net_id);
504 tun = tun_get_by_name(tn, ifr->ifr_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505 if (tun) {
506 if (tun->attached)
507 return -EBUSY;
508
509 /* Check permissions */
Guido Guenther8c644622007-07-02 22:50:25 -0700510 if (((tun->owner != -1 &&
511 current->euid != tun->owner) ||
512 (tun->group != -1 &&
513 current->egid != tun->group)) &&
514 !capable(CAP_NET_ADMIN))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515 return -EPERM;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400516 }
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700517 else if (__dev_get_by_name(net, ifr->ifr_name))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 return -EINVAL;
519 else {
520 char *name;
521 unsigned long flags = 0;
522
523 err = -EINVAL;
524
David Woodhouseca6bb5d2006-06-22 16:07:52 -0700525 if (!capable(CAP_NET_ADMIN))
526 return -EPERM;
527
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 /* Set dev type */
529 if (ifr->ifr_flags & IFF_TUN) {
530 /* TUN device */
531 flags |= TUN_TUN_DEV;
532 name = "tun%d";
533 } else if (ifr->ifr_flags & IFF_TAP) {
534 /* TAP device */
535 flags |= TUN_TAP_DEV;
536 name = "tap%d";
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400537 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 goto failed;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400539
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 if (*ifr->ifr_name)
541 name = ifr->ifr_name;
542
543 dev = alloc_netdev(sizeof(struct tun_struct), name,
544 tun_setup);
545 if (!dev)
546 return -ENOMEM;
547
Pavel Emelyanovfc54c652008-04-16 00:41:53 -0700548 dev_net_set(dev, net);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 tun = netdev_priv(dev);
550 tun->dev = dev;
551 tun->flags = flags;
552 /* Be promiscuous by default to maintain previous behaviour. */
553 tun->if_flags = IFF_PROMISC;
554 /* Generate random Ethernet address. */
Al Viroa3edb082007-12-22 17:52:42 +0000555 *(__be16 *)tun->dev_addr = htons(0x00FF);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 get_random_bytes(tun->dev_addr + sizeof(u16), 4);
557 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
558
559 tun_net_init(dev);
560
561 if (strchr(dev->name, '%')) {
562 err = dev_alloc_name(dev, dev->name);
563 if (err < 0)
564 goto err_free_dev;
565 }
566
567 err = register_netdevice(tun->dev);
568 if (err < 0)
569 goto err_free_dev;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400570
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700571 list_add(&tun->list, &tn->dev_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 }
573
574 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
575
576 if (ifr->ifr_flags & IFF_NO_PI)
577 tun->flags |= TUN_NO_PI;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -0800578 else
579 tun->flags &= ~TUN_NO_PI;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580
581 if (ifr->ifr_flags & IFF_ONE_QUEUE)
582 tun->flags |= TUN_ONE_QUEUE;
Nathaniel Filardoa26af1e2008-02-05 03:05:07 -0800583 else
584 tun->flags &= ~TUN_ONE_QUEUE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585
586 file->private_data = tun;
587 tun->attached = 1;
Pavel Emelyanovfc54c652008-04-16 00:41:53 -0700588 get_net(dev_net(tun->dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589
590 strcpy(ifr->ifr_name, tun->dev->name);
591 return 0;
592
593 err_free_dev:
594 free_netdev(dev);
595 failed:
596 return err;
597}
598
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400599static int tun_chr_ioctl(struct inode *inode, struct file *file,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 unsigned int cmd, unsigned long arg)
601{
602 struct tun_struct *tun = file->private_data;
603 void __user* argp = (void __user*)arg;
604 struct ifreq ifr;
Joe Perches0795af52007-10-03 17:59:30 -0700605 DECLARE_MAC_BUF(mac);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606
607 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
608 if (copy_from_user(&ifr, argp, sizeof ifr))
609 return -EFAULT;
610
611 if (cmd == TUNSETIFF && !tun) {
612 int err;
613
614 ifr.ifr_name[IFNAMSIZ-1] = '\0';
615
616 rtnl_lock();
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700617 err = tun_set_iff(current->nsproxy->net_ns, file, &ifr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 rtnl_unlock();
619
620 if (err)
621 return err;
622
623 if (copy_to_user(argp, &ifr, sizeof(ifr)))
624 return -EFAULT;
625 return 0;
626 }
627
628 if (!tun)
629 return -EBADFD;
630
631 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
632
633 switch (cmd) {
634 case TUNSETNOCSUM:
635 /* Disable/Enable checksum */
636 if (arg)
637 tun->flags |= TUN_NOCHECKSUM;
638 else
639 tun->flags &= ~TUN_NOCHECKSUM;
640
641 DBG(KERN_INFO "%s: checksum %s\n",
642 tun->dev->name, arg ? "disabled" : "enabled");
643 break;
644
645 case TUNSETPERSIST:
646 /* Disable/Enable persist mode */
647 if (arg)
648 tun->flags |= TUN_PERSIST;
649 else
650 tun->flags &= ~TUN_PERSIST;
651
652 DBG(KERN_INFO "%s: persist %s\n",
Toyo Abec6e991d2007-12-24 21:29:35 -0800653 tun->dev->name, arg ? "enabled" : "disabled");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 break;
655
656 case TUNSETOWNER:
657 /* Set owner of the device */
658 tun->owner = (uid_t) arg;
659
660 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
661 break;
662
Guido Guenther8c644622007-07-02 22:50:25 -0700663 case TUNSETGROUP:
664 /* Set group of the device */
665 tun->group= (gid_t) arg;
666
667 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
668 break;
669
Mike Kershawff4cc3a2005-09-01 17:40:05 -0700670 case TUNSETLINK:
David S. Miller48abfe02008-04-23 19:37:58 -0700671 {
672 int ret;
673
Mike Kershawff4cc3a2005-09-01 17:40:05 -0700674 /* Only allow setting the type when the interface is down */
David S. Miller48abfe02008-04-23 19:37:58 -0700675 rtnl_lock();
Mike Kershawff4cc3a2005-09-01 17:40:05 -0700676 if (tun->dev->flags & IFF_UP) {
677 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
678 tun->dev->name);
David S. Miller48abfe02008-04-23 19:37:58 -0700679 ret = -EBUSY;
Mike Kershawff4cc3a2005-09-01 17:40:05 -0700680 } else {
681 tun->dev->type = (int) arg;
682 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
David S. Miller48abfe02008-04-23 19:37:58 -0700683 ret = 0;
Mike Kershawff4cc3a2005-09-01 17:40:05 -0700684 }
David S. Miller48abfe02008-04-23 19:37:58 -0700685 rtnl_unlock();
686 return ret;
687 }
Mike Kershawff4cc3a2005-09-01 17:40:05 -0700688
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689#ifdef TUN_DEBUG
690 case TUNSETDEBUG:
691 tun->debug = arg;
692 break;
693#endif
694
695 case SIOCGIFFLAGS:
696 ifr.ifr_flags = tun->if_flags;
697 if (copy_to_user( argp, &ifr, sizeof ifr))
698 return -EFAULT;
699 return 0;
700
701 case SIOCSIFFLAGS:
702 /** Set the character device's interface flags. Currently only
703 * IFF_PROMISC and IFF_ALLMULTI are used. */
704 tun->if_flags = ifr.ifr_flags;
705 DBG(KERN_INFO "%s: interface flags 0x%lx\n",
706 tun->dev->name, tun->if_flags);
707 return 0;
708
709 case SIOCGIFHWADDR:
Brian Braunstein36226a82007-04-26 01:00:55 -0700710 /* Note: the actual net device's address may be different */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
712 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
713 if (copy_to_user( argp, &ifr, sizeof ifr))
714 return -EFAULT;
715 return 0;
716
717 case SIOCSIFHWADDR:
Brian Braunstein36226a82007-04-26 01:00:55 -0700718 {
719 /* try to set the actual net device's hw address */
Kim B. Heino40102372008-02-29 12:26:21 -0800720 int ret;
721
722 rtnl_lock();
723 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
724 rtnl_unlock();
Brian Braunstein36226a82007-04-26 01:00:55 -0700725
726 if (ret == 0) {
727 /** Set the character device's hardware address. This is used when
728 * filtering packets being sent from the network device to the character
729 * device. */
730 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
731 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
732 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
733 tun->dev->name,
734 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
735 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
736 }
737
738 return ret;
739 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740
741 case SIOCADDMULTI:
742 /** Add the specified group to the character device's multicast filter
743 * list. */
David S. Miller9edb74c2008-04-24 03:44:43 -0700744 rtnl_lock();
745 netif_tx_lock_bh(tun->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
David S. Miller9edb74c2008-04-24 03:44:43 -0700747 netif_tx_unlock_bh(tun->dev);
748 rtnl_unlock();
749
Joe Perches0795af52007-10-03 17:59:30 -0700750 DBG(KERN_DEBUG "%s: add multi: %s\n",
751 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 return 0;
753
754 case SIOCDELMULTI:
755 /** Remove the specified group from the character device's multicast
756 * filter list. */
David S. Miller9edb74c2008-04-24 03:44:43 -0700757 rtnl_lock();
758 netif_tx_lock_bh(tun->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
David S. Miller9edb74c2008-04-24 03:44:43 -0700760 netif_tx_unlock_bh(tun->dev);
761 rtnl_unlock();
762
Joe Perches0795af52007-10-03 17:59:30 -0700763 DBG(KERN_DEBUG "%s: del multi: %s\n",
764 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 return 0;
766
767 default:
768 return -EINVAL;
769 };
770
771 return 0;
772}
773
774static int tun_chr_fasync(int fd, struct file *file, int on)
775{
776 struct tun_struct *tun = file->private_data;
777 int ret;
778
779 if (!tun)
780 return -EBADFD;
781
782 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
783
784 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400785 return ret;
786
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787 if (on) {
Eric W. Biederman609d7fa2006-10-02 02:17:15 -0700788 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 if (ret)
790 return ret;
791 tun->flags |= TUN_FASYNC;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400792 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 tun->flags &= ~TUN_FASYNC;
794
795 return 0;
796}
797
798static int tun_chr_open(struct inode *inode, struct file * file)
799{
800 DBG1(KERN_INFO "tunX: tun_chr_open\n");
801 file->private_data = NULL;
802 return 0;
803}
804
805static int tun_chr_close(struct inode *inode, struct file *file)
806{
807 struct tun_struct *tun = file->private_data;
808
809 if (!tun)
810 return 0;
811
812 DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
813
814 tun_chr_fasync(-1, file, 0);
815
816 rtnl_lock();
817
818 /* Detach from net device */
819 file->private_data = NULL;
820 tun->attached = 0;
Pavel Emelyanovfc54c652008-04-16 00:41:53 -0700821 put_net(dev_net(tun->dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822
823 /* Drop read queue */
824 skb_queue_purge(&tun->readq);
825
826 if (!(tun->flags & TUN_PERSIST)) {
827 list_del(&tun->list);
828 unregister_netdevice(tun->dev);
829 }
830
831 rtnl_unlock();
832
833 return 0;
834}
835
Arjan van de Vend54b1fd2007-02-12 00:55:34 -0800836static const struct file_operations tun_fops = {
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400837 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 .llseek = no_llseek,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700839 .read = do_sync_read,
840 .aio_read = tun_chr_aio_read,
841 .write = do_sync_write,
842 .aio_write = tun_chr_aio_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843 .poll = tun_chr_poll,
844 .ioctl = tun_chr_ioctl,
845 .open = tun_chr_open,
846 .release = tun_chr_close,
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400847 .fasync = tun_chr_fasync
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848};
849
850static struct miscdevice tun_miscdev = {
851 .minor = TUN_MINOR,
852 .name = "tun",
853 .fops = &tun_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854};
855
856/* ethtool interface */
857
858static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
859{
860 cmd->supported = 0;
861 cmd->advertising = 0;
862 cmd->speed = SPEED_10;
863 cmd->duplex = DUPLEX_FULL;
864 cmd->port = PORT_TP;
865 cmd->phy_address = 0;
866 cmd->transceiver = XCVR_INTERNAL;
867 cmd->autoneg = AUTONEG_DISABLE;
868 cmd->maxtxpkt = 0;
869 cmd->maxrxpkt = 0;
870 return 0;
871}
872
873static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
874{
875 struct tun_struct *tun = netdev_priv(dev);
876
877 strcpy(info->driver, DRV_NAME);
878 strcpy(info->version, DRV_VERSION);
879 strcpy(info->fw_version, "N/A");
880
881 switch (tun->flags & TUN_TYPE_MASK) {
882 case TUN_TUN_DEV:
883 strcpy(info->bus_info, "tun");
884 break;
885 case TUN_TAP_DEV:
886 strcpy(info->bus_info, "tap");
887 break;
888 }
889}
890
891static u32 tun_get_msglevel(struct net_device *dev)
892{
893#ifdef TUN_DEBUG
894 struct tun_struct *tun = netdev_priv(dev);
895 return tun->debug;
896#else
897 return -EOPNOTSUPP;
898#endif
899}
900
901static void tun_set_msglevel(struct net_device *dev, u32 value)
902{
903#ifdef TUN_DEBUG
904 struct tun_struct *tun = netdev_priv(dev);
905 tun->debug = value;
906#endif
907}
908
909static u32 tun_get_link(struct net_device *dev)
910{
911 struct tun_struct *tun = netdev_priv(dev);
912 return tun->attached;
913}
914
915static u32 tun_get_rx_csum(struct net_device *dev)
916{
917 struct tun_struct *tun = netdev_priv(dev);
918 return (tun->flags & TUN_NOCHECKSUM) == 0;
919}
920
921static int tun_set_rx_csum(struct net_device *dev, u32 data)
922{
923 struct tun_struct *tun = netdev_priv(dev);
924 if (data)
925 tun->flags &= ~TUN_NOCHECKSUM;
926 else
927 tun->flags |= TUN_NOCHECKSUM;
928 return 0;
929}
930
Jeff Garzik7282d492006-09-13 14:30:00 -0400931static const struct ethtool_ops tun_ethtool_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 .get_settings = tun_get_settings,
933 .get_drvinfo = tun_get_drvinfo,
934 .get_msglevel = tun_get_msglevel,
935 .set_msglevel = tun_set_msglevel,
936 .get_link = tun_get_link,
937 .get_rx_csum = tun_get_rx_csum,
938 .set_rx_csum = tun_set_rx_csum
939};
940
Pavel Emelyanov79d17602008-04-16 00:40:46 -0700941static int tun_init_net(struct net *net)
942{
943 struct tun_net *tn;
944
945 tn = kmalloc(sizeof(*tn), GFP_KERNEL);
946 if (tn == NULL)
947 return -ENOMEM;
948
949 INIT_LIST_HEAD(&tn->dev_list);
950
951 if (net_assign_generic(net, tun_net_id, tn)) {
952 kfree(tn);
953 return -ENOMEM;
954 }
955
956 return 0;
957}
958
959static void tun_exit_net(struct net *net)
960{
961 struct tun_net *tn;
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700962 struct tun_struct *tun, *nxt;
Pavel Emelyanov79d17602008-04-16 00:40:46 -0700963
964 tn = net_generic(net, tun_net_id);
Pavel Emelyanovd647a592008-04-16 00:41:16 -0700965
966 rtnl_lock();
967 list_for_each_entry_safe(tun, nxt, &tn->dev_list, list) {
968 DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
969 unregister_netdevice(tun->dev);
970 }
971 rtnl_unlock();
972
Pavel Emelyanov79d17602008-04-16 00:40:46 -0700973 kfree(tn);
974}
975
976static struct pernet_operations tun_net_ops = {
977 .init = tun_init_net,
978 .exit = tun_exit_net,
979};
980
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981static int __init tun_init(void)
982{
983 int ret = 0;
984
985 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
986 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
987
Pavel Emelyanov79d17602008-04-16 00:40:46 -0700988 ret = register_pernet_gen_device(&tun_net_id, &tun_net_ops);
989 if (ret) {
990 printk(KERN_ERR "tun: Can't register pernet ops\n");
991 goto err_pernet;
992 }
993
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994 ret = misc_register(&tun_miscdev);
Pavel Emelyanov79d17602008-04-16 00:40:46 -0700995 if (ret) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
Pavel Emelyanov79d17602008-04-16 00:40:46 -0700997 goto err_misc;
998 }
999 return 0;
1000
1001err_misc:
1002 unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
1003err_pernet:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 return ret;
1005}
1006
1007static void tun_cleanup(void)
1008{
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001009 misc_deregister(&tun_miscdev);
Pavel Emelyanov79d17602008-04-16 00:40:46 -07001010 unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011}
1012
1013module_init(tun_init);
1014module_exit(tun_cleanup);
1015MODULE_DESCRIPTION(DRV_DESCRIPTION);
1016MODULE_AUTHOR(DRV_COPYRIGHT);
1017MODULE_LICENSE("GPL");
1018MODULE_ALIAS_MISCDEV(TUN_MINOR);