blob: 1f76446959765ef577382517e7039c0ab044d5c3 [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>
Eric W. Biederman881d9662007-09-17 11:56:21 -070065#include <net/net_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070066
67#include <asm/system.h>
68#include <asm/uaccess.h>
69
70#ifdef TUN_DEBUG
71static int debug;
72#endif
73
74/* Network device part of the driver */
75
76static LIST_HEAD(tun_dev_list);
Jeff Garzik7282d492006-09-13 14:30:00 -040077static const struct ethtool_ops tun_ethtool_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79/* Net device open. */
80static int tun_net_open(struct net_device *dev)
81{
82 netif_start_queue(dev);
83 return 0;
84}
85
86/* Net device close. */
87static int tun_net_close(struct net_device *dev)
88{
89 netif_stop_queue(dev);
90 return 0;
91}
92
93/* Net device start xmit */
94static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
95{
96 struct tun_struct *tun = netdev_priv(dev);
97
98 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
99
100 /* Drop packet if interface is not attached */
101 if (!tun->attached)
102 goto drop;
103
104 /* Packet dropping */
105 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
106 if (!(tun->flags & TUN_ONE_QUEUE)) {
107 /* Normal queueing mode. */
108 /* Packet scheduler handles dropping of further packets. */
109 netif_stop_queue(dev);
110
111 /* We won't see all dropped packets individually, so overrun
112 * error is more appropriate. */
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700113 dev->stats.tx_fifo_errors++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 } else {
115 /* Single queue mode.
116 * Driver handles dropping of all packets itself. */
117 goto drop;
118 }
119 }
120
121 /* Queue packet */
122 skb_queue_tail(&tun->readq, skb);
123 dev->trans_start = jiffies;
124
125 /* Notify and wake up reader process */
126 if (tun->flags & TUN_FASYNC)
127 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
128 wake_up_interruptible(&tun->read_wait);
129 return 0;
130
131drop:
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700132 dev->stats.tx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 kfree_skb(skb);
134 return 0;
135}
136
137/** Add the specified Ethernet address to this multicast filter. */
138static void
139add_multi(u32* filter, const u8* addr)
140{
141 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
142 filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
143}
144
145/** Remove the specified Ethernet addres from this multicast filter. */
146static void
147del_multi(u32* filter, const u8* addr)
148{
149 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
150 filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31));
151}
152
153/** Update the list of multicast groups to which the network device belongs.
154 * This list is used to filter packets being sent from the character device to
155 * the network device. */
156static void
157tun_net_mclist(struct net_device *dev)
158{
159 struct tun_struct *tun = netdev_priv(dev);
160 const struct dev_mc_list *mclist;
161 int i;
Joe Perches0795af52007-10-03 17:59:30 -0700162 DECLARE_MAC_BUF(mac);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n",
164 dev->name, dev->mc_count);
165 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
166 for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL;
167 i++, mclist = mclist->next) {
168 add_multi(tun->net_filter, mclist->dmi_addr);
Joe Perches0795af52007-10-03 17:59:30 -0700169 DBG(KERN_DEBUG "%s: tun_net_mclist: %s\n",
170 dev->name, print_mac(mac, mclist->dmi_addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 }
172}
173
Ed Swierk4885a502007-09-16 12:21:38 -0700174#define MIN_MTU 68
175#define MAX_MTU 65535
176
177static int
178tun_net_change_mtu(struct net_device *dev, int new_mtu)
179{
180 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
181 return -EINVAL;
182 dev->mtu = new_mtu;
183 return 0;
184}
185
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186/* Initialize net device. */
187static void tun_net_init(struct net_device *dev)
188{
189 struct tun_struct *tun = netdev_priv(dev);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400190
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 switch (tun->flags & TUN_TYPE_MASK) {
192 case TUN_TUN_DEV:
193 /* Point-to-Point TUN Device */
194 dev->hard_header_len = 0;
195 dev->addr_len = 0;
196 dev->mtu = 1500;
Ed Swierk4885a502007-09-16 12:21:38 -0700197 dev->change_mtu = tun_net_change_mtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198
199 /* Zero header length */
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400200 dev->type = ARPHRD_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
202 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
203 break;
204
205 case TUN_TAP_DEV:
206 /* Ethernet TAP Device */
207 dev->set_multicast_list = tun_net_mclist;
208
209 ether_setup(dev);
Ed Swierk4885a502007-09-16 12:21:38 -0700210 dev->change_mtu = tun_net_change_mtu;
Brian Braunstein36226a82007-04-26 01:00:55 -0700211
212 /* random address already created for us by tun_set_iff, use it */
213 memcpy(dev->dev_addr, tun->dev_addr, min(sizeof(tun->dev_addr), sizeof(dev->dev_addr)) );
214
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
216 break;
217 }
218}
219
220/* Character device part */
221
222/* Poll */
223static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400224{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 struct tun_struct *tun = file->private_data;
226 unsigned int mask = POLLOUT | POLLWRNORM;
227
228 if (!tun)
229 return -EBADFD;
230
231 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
232
233 poll_wait(file, &tun->read_wait, wait);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400234
David S. Millerb03efcf2005-07-08 14:57:23 -0700235 if (!skb_queue_empty(&tun->readq))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 mask |= POLLIN | POLLRDNORM;
237
238 return mask;
239}
240
241/* Get packet from user space buffer */
242static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
243{
244 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
245 struct sk_buff *skb;
246 size_t len = count, align = 0;
247
248 if (!(tun->flags & TUN_NO_PI)) {
249 if ((len -= sizeof(pi)) > count)
250 return -EINVAL;
251
252 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
253 return -EFAULT;
254 }
255
256 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV)
257 align = NET_IP_ALIGN;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400258
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700260 tun->dev->stats.rx_dropped++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 return -ENOMEM;
262 }
263
264 if (align)
265 skb_reserve(skb, align);
Dave Jones8f227572006-03-11 18:49:13 -0800266 if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700267 tun->dev->stats.rx_dropped++;
Dave Jones8f227572006-03-11 18:49:13 -0800268 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 return -EFAULT;
Dave Jones8f227572006-03-11 18:49:13 -0800270 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 switch (tun->flags & TUN_TYPE_MASK) {
273 case TUN_TUN_DEV:
Arnaldo Carvalho de Melo459a98e2007-03-19 15:30:44 -0700274 skb_reset_mac_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 skb->protocol = pi.proto;
Arnaldo Carvalho de Melo4c13eb62007-04-25 17:40:23 -0700276 skb->dev = tun->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 break;
278 case TUN_TAP_DEV:
279 skb->protocol = eth_type_trans(skb, tun->dev);
280 break;
281 };
282
283 if (tun->flags & TUN_NOCHECKSUM)
284 skb->ip_summed = CHECKSUM_UNNECESSARY;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400285
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 netif_rx_ni(skb);
287 tun->dev->last_rx = jiffies;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400288
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700289 tun->dev->stats.rx_packets++;
290 tun->dev->stats.rx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291
292 return count;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400293}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294
295static inline size_t iov_total(const struct iovec *iv, unsigned long count)
296{
297 unsigned long i;
298 size_t len;
299
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400300 for (i = 0, len = 0; i < count; i++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 len += iv[i].iov_len;
302
303 return len;
304}
305
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700306static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
307 unsigned long count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308{
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700309 struct tun_struct *tun = iocb->ki_filp->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310
311 if (!tun)
312 return -EBADFD;
313
314 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
315
316 return tun_get_user(tun, (struct iovec *) iv, iov_total(iv, count));
317}
318
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319/* Put packet to the user space buffer */
320static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
321 struct sk_buff *skb,
322 struct iovec *iv, int len)
323{
324 struct tun_pi pi = { 0, skb->protocol };
325 ssize_t total = 0;
326
327 if (!(tun->flags & TUN_NO_PI)) {
328 if ((len -= sizeof(pi)) < 0)
329 return -EINVAL;
330
331 if (len < skb->len) {
332 /* Packet will be striped */
333 pi.flags |= TUN_PKT_STRIP;
334 }
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400335
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
337 return -EFAULT;
338 total += sizeof(pi);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400339 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
341 len = min_t(int, skb->len, len);
342
343 skb_copy_datagram_iovec(skb, 0, iv, len);
344 total += len;
345
Jeff Garzik09f75cd2007-10-03 17:41:50 -0700346 tun->dev->stats.tx_packets++;
347 tun->dev->stats.tx_bytes += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348
349 return total;
350}
351
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700352static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
353 unsigned long count, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354{
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700355 struct file *file = iocb->ki_filp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 struct tun_struct *tun = file->private_data;
357 DECLARE_WAITQUEUE(wait, current);
358 struct sk_buff *skb;
359 ssize_t len, ret = 0;
Joe Perches0795af52007-10-03 17:59:30 -0700360 DECLARE_MAC_BUF(mac);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361
362 if (!tun)
363 return -EBADFD;
364
365 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
366
367 len = iov_total(iv, count);
368 if (len < 0)
369 return -EINVAL;
370
371 add_wait_queue(&tun->read_wait, &wait);
372 while (len) {
373 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
374 u8 addr[ ETH_ALEN];
375 int bit_nr;
376
377 current->state = TASK_INTERRUPTIBLE;
378
379 /* Read frames from the queue */
380 if (!(skb=skb_dequeue(&tun->readq))) {
381 if (file->f_flags & O_NONBLOCK) {
382 ret = -EAGAIN;
383 break;
384 }
385 if (signal_pending(current)) {
386 ret = -ERESTARTSYS;
387 break;
388 }
389
390 /* Nothing to read, let's sleep */
391 schedule();
392 continue;
393 }
394 netif_wake_queue(tun->dev);
395
396 /** Decide whether to accept this packet. This code is designed to
397 * behave identically to an Ethernet interface. Accept the packet if
398 * - we are promiscuous.
399 * - the packet is addressed to us.
400 * - the packet is broadcast.
401 * - the packet is multicast and
402 * - we are multicast promiscous.
403 * - we belong to the multicast group.
404 */
Arnaldo Carvalho de Melod626f622007-03-27 18:55:52 -0300405 skb_copy_from_linear_data(skb, addr, min_t(size_t, sizeof addr,
406 skb->len));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 bit_nr = ether_crc(sizeof addr, addr) >> 26;
408 if ((tun->if_flags & IFF_PROMISC) ||
409 memcmp(addr, tun->dev_addr, sizeof addr) == 0 ||
410 memcmp(addr, ones, sizeof addr) == 0 ||
411 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) ||
412 (addr[0] == 0x33 && addr[1] == 0x33)) &&
413 ((tun->if_flags & IFF_ALLMULTI) ||
414 (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) {
Joe Perches0795af52007-10-03 17:59:30 -0700415 DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %s\n",
416 tun->dev->name, print_mac(mac, addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
418 kfree_skb(skb);
419 break;
420 } else {
Joe Perches0795af52007-10-03 17:59:30 -0700421 DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %s\n",
422 tun->dev->name, print_mac(mac, addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 kfree_skb(skb);
424 continue;
425 }
426 }
427
428 current->state = TASK_RUNNING;
429 remove_wait_queue(&tun->read_wait, &wait);
430
431 return ret;
432}
433
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434static void tun_setup(struct net_device *dev)
435{
436 struct tun_struct *tun = netdev_priv(dev);
437
438 skb_queue_head_init(&tun->readq);
439 init_waitqueue_head(&tun->read_wait);
440
441 tun->owner = -1;
Guido Guenther8c644622007-07-02 22:50:25 -0700442 tun->group = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 dev->open = tun_net_open;
445 dev->hard_start_xmit = tun_net_xmit;
446 dev->stop = tun_net_close;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 dev->ethtool_ops = &tun_ethtool_ops;
448 dev->destructor = free_netdev;
449}
450
451static struct tun_struct *tun_get_by_name(const char *name)
452{
453 struct tun_struct *tun;
454
455 ASSERT_RTNL();
456 list_for_each_entry(tun, &tun_dev_list, list) {
457 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
458 return tun;
459 }
460
461 return NULL;
462}
463
464static int tun_set_iff(struct file *file, struct ifreq *ifr)
465{
466 struct tun_struct *tun;
467 struct net_device *dev;
468 int err;
469
470 tun = tun_get_by_name(ifr->ifr_name);
471 if (tun) {
472 if (tun->attached)
473 return -EBUSY;
474
475 /* Check permissions */
Guido Guenther8c644622007-07-02 22:50:25 -0700476 if (((tun->owner != -1 &&
477 current->euid != tun->owner) ||
478 (tun->group != -1 &&
479 current->egid != tun->group)) &&
480 !capable(CAP_NET_ADMIN))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 return -EPERM;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400482 }
Eric W. Biederman881d9662007-09-17 11:56:21 -0700483 else if (__dev_get_by_name(&init_net, ifr->ifr_name))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 return -EINVAL;
485 else {
486 char *name;
487 unsigned long flags = 0;
488
489 err = -EINVAL;
490
David Woodhouseca6bb5d2006-06-22 16:07:52 -0700491 if (!capable(CAP_NET_ADMIN))
492 return -EPERM;
493
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494 /* Set dev type */
495 if (ifr->ifr_flags & IFF_TUN) {
496 /* TUN device */
497 flags |= TUN_TUN_DEV;
498 name = "tun%d";
499 } else if (ifr->ifr_flags & IFF_TAP) {
500 /* TAP device */
501 flags |= TUN_TAP_DEV;
502 name = "tap%d";
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400503 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 goto failed;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400505
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 if (*ifr->ifr_name)
507 name = ifr->ifr_name;
508
509 dev = alloc_netdev(sizeof(struct tun_struct), name,
510 tun_setup);
511 if (!dev)
512 return -ENOMEM;
513
514 tun = netdev_priv(dev);
515 tun->dev = dev;
516 tun->flags = flags;
517 /* Be promiscuous by default to maintain previous behaviour. */
518 tun->if_flags = IFF_PROMISC;
519 /* Generate random Ethernet address. */
520 *(u16 *)tun->dev_addr = htons(0x00FF);
521 get_random_bytes(tun->dev_addr + sizeof(u16), 4);
522 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
523
524 tun_net_init(dev);
525
526 if (strchr(dev->name, '%')) {
527 err = dev_alloc_name(dev, dev->name);
528 if (err < 0)
529 goto err_free_dev;
530 }
531
532 err = register_netdevice(tun->dev);
533 if (err < 0)
534 goto err_free_dev;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400535
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 list_add(&tun->list, &tun_dev_list);
537 }
538
539 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
540
541 if (ifr->ifr_flags & IFF_NO_PI)
542 tun->flags |= TUN_NO_PI;
543
544 if (ifr->ifr_flags & IFF_ONE_QUEUE)
545 tun->flags |= TUN_ONE_QUEUE;
546
547 file->private_data = tun;
548 tun->attached = 1;
549
550 strcpy(ifr->ifr_name, tun->dev->name);
551 return 0;
552
553 err_free_dev:
554 free_netdev(dev);
555 failed:
556 return err;
557}
558
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400559static int tun_chr_ioctl(struct inode *inode, struct file *file,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 unsigned int cmd, unsigned long arg)
561{
562 struct tun_struct *tun = file->private_data;
563 void __user* argp = (void __user*)arg;
564 struct ifreq ifr;
Joe Perches0795af52007-10-03 17:59:30 -0700565 DECLARE_MAC_BUF(mac);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566
567 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
568 if (copy_from_user(&ifr, argp, sizeof ifr))
569 return -EFAULT;
570
571 if (cmd == TUNSETIFF && !tun) {
572 int err;
573
574 ifr.ifr_name[IFNAMSIZ-1] = '\0';
575
576 rtnl_lock();
577 err = tun_set_iff(file, &ifr);
578 rtnl_unlock();
579
580 if (err)
581 return err;
582
583 if (copy_to_user(argp, &ifr, sizeof(ifr)))
584 return -EFAULT;
585 return 0;
586 }
587
588 if (!tun)
589 return -EBADFD;
590
591 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
592
593 switch (cmd) {
594 case TUNSETNOCSUM:
595 /* Disable/Enable checksum */
596 if (arg)
597 tun->flags |= TUN_NOCHECKSUM;
598 else
599 tun->flags &= ~TUN_NOCHECKSUM;
600
601 DBG(KERN_INFO "%s: checksum %s\n",
602 tun->dev->name, arg ? "disabled" : "enabled");
603 break;
604
605 case TUNSETPERSIST:
606 /* Disable/Enable persist mode */
607 if (arg)
608 tun->flags |= TUN_PERSIST;
609 else
610 tun->flags &= ~TUN_PERSIST;
611
612 DBG(KERN_INFO "%s: persist %s\n",
613 tun->dev->name, arg ? "disabled" : "enabled");
614 break;
615
616 case TUNSETOWNER:
617 /* Set owner of the device */
618 tun->owner = (uid_t) arg;
619
620 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
621 break;
622
Guido Guenther8c644622007-07-02 22:50:25 -0700623 case TUNSETGROUP:
624 /* Set group of the device */
625 tun->group= (gid_t) arg;
626
627 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
628 break;
629
Mike Kershawff4cc3a2005-09-01 17:40:05 -0700630 case TUNSETLINK:
631 /* Only allow setting the type when the interface is down */
632 if (tun->dev->flags & IFF_UP) {
633 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
634 tun->dev->name);
635 return -EBUSY;
636 } else {
637 tun->dev->type = (int) arg;
638 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
639 }
640 break;
641
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642#ifdef TUN_DEBUG
643 case TUNSETDEBUG:
644 tun->debug = arg;
645 break;
646#endif
647
648 case SIOCGIFFLAGS:
649 ifr.ifr_flags = tun->if_flags;
650 if (copy_to_user( argp, &ifr, sizeof ifr))
651 return -EFAULT;
652 return 0;
653
654 case SIOCSIFFLAGS:
655 /** Set the character device's interface flags. Currently only
656 * IFF_PROMISC and IFF_ALLMULTI are used. */
657 tun->if_flags = ifr.ifr_flags;
658 DBG(KERN_INFO "%s: interface flags 0x%lx\n",
659 tun->dev->name, tun->if_flags);
660 return 0;
661
662 case SIOCGIFHWADDR:
Brian Braunstein36226a82007-04-26 01:00:55 -0700663 /* Note: the actual net device's address may be different */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
665 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
666 if (copy_to_user( argp, &ifr, sizeof ifr))
667 return -EFAULT;
668 return 0;
669
670 case SIOCSIFHWADDR:
Brian Braunstein36226a82007-04-26 01:00:55 -0700671 {
672 /* try to set the actual net device's hw address */
673 int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
674
675 if (ret == 0) {
676 /** Set the character device's hardware address. This is used when
677 * filtering packets being sent from the network device to the character
678 * device. */
679 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
680 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
681 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
682 tun->dev->name,
683 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
684 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
685 }
686
687 return ret;
688 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689
690 case SIOCADDMULTI:
691 /** Add the specified group to the character device's multicast filter
692 * list. */
693 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
Joe Perches0795af52007-10-03 17:59:30 -0700694 DBG(KERN_DEBUG "%s: add multi: %s\n",
695 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 return 0;
697
698 case SIOCDELMULTI:
699 /** Remove the specified group from the character device's multicast
700 * filter list. */
701 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
Joe Perches0795af52007-10-03 17:59:30 -0700702 DBG(KERN_DEBUG "%s: del multi: %s\n",
703 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704 return 0;
705
706 default:
707 return -EINVAL;
708 };
709
710 return 0;
711}
712
713static int tun_chr_fasync(int fd, struct file *file, int on)
714{
715 struct tun_struct *tun = file->private_data;
716 int ret;
717
718 if (!tun)
719 return -EBADFD;
720
721 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
722
723 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400724 return ret;
725
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 if (on) {
Eric W. Biederman609d7fa2006-10-02 02:17:15 -0700727 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 if (ret)
729 return ret;
730 tun->flags |= TUN_FASYNC;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400731 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 tun->flags &= ~TUN_FASYNC;
733
734 return 0;
735}
736
737static int tun_chr_open(struct inode *inode, struct file * file)
738{
739 DBG1(KERN_INFO "tunX: tun_chr_open\n");
740 file->private_data = NULL;
741 return 0;
742}
743
744static int tun_chr_close(struct inode *inode, struct file *file)
745{
746 struct tun_struct *tun = file->private_data;
747
748 if (!tun)
749 return 0;
750
751 DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
752
753 tun_chr_fasync(-1, file, 0);
754
755 rtnl_lock();
756
757 /* Detach from net device */
758 file->private_data = NULL;
759 tun->attached = 0;
760
761 /* Drop read queue */
762 skb_queue_purge(&tun->readq);
763
764 if (!(tun->flags & TUN_PERSIST)) {
765 list_del(&tun->list);
766 unregister_netdevice(tun->dev);
767 }
768
769 rtnl_unlock();
770
771 return 0;
772}
773
Arjan van de Vend54b1fd2007-02-12 00:55:34 -0800774static const struct file_operations tun_fops = {
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400775 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 .llseek = no_llseek,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -0700777 .read = do_sync_read,
778 .aio_read = tun_chr_aio_read,
779 .write = do_sync_write,
780 .aio_write = tun_chr_aio_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 .poll = tun_chr_poll,
782 .ioctl = tun_chr_ioctl,
783 .open = tun_chr_open,
784 .release = tun_chr_close,
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400785 .fasync = tun_chr_fasync
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786};
787
788static struct miscdevice tun_miscdev = {
789 .minor = TUN_MINOR,
790 .name = "tun",
791 .fops = &tun_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792};
793
794/* ethtool interface */
795
796static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
797{
798 cmd->supported = 0;
799 cmd->advertising = 0;
800 cmd->speed = SPEED_10;
801 cmd->duplex = DUPLEX_FULL;
802 cmd->port = PORT_TP;
803 cmd->phy_address = 0;
804 cmd->transceiver = XCVR_INTERNAL;
805 cmd->autoneg = AUTONEG_DISABLE;
806 cmd->maxtxpkt = 0;
807 cmd->maxrxpkt = 0;
808 return 0;
809}
810
811static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
812{
813 struct tun_struct *tun = netdev_priv(dev);
814
815 strcpy(info->driver, DRV_NAME);
816 strcpy(info->version, DRV_VERSION);
817 strcpy(info->fw_version, "N/A");
818
819 switch (tun->flags & TUN_TYPE_MASK) {
820 case TUN_TUN_DEV:
821 strcpy(info->bus_info, "tun");
822 break;
823 case TUN_TAP_DEV:
824 strcpy(info->bus_info, "tap");
825 break;
826 }
827}
828
829static u32 tun_get_msglevel(struct net_device *dev)
830{
831#ifdef TUN_DEBUG
832 struct tun_struct *tun = netdev_priv(dev);
833 return tun->debug;
834#else
835 return -EOPNOTSUPP;
836#endif
837}
838
839static void tun_set_msglevel(struct net_device *dev, u32 value)
840{
841#ifdef TUN_DEBUG
842 struct tun_struct *tun = netdev_priv(dev);
843 tun->debug = value;
844#endif
845}
846
847static u32 tun_get_link(struct net_device *dev)
848{
849 struct tun_struct *tun = netdev_priv(dev);
850 return tun->attached;
851}
852
853static u32 tun_get_rx_csum(struct net_device *dev)
854{
855 struct tun_struct *tun = netdev_priv(dev);
856 return (tun->flags & TUN_NOCHECKSUM) == 0;
857}
858
859static int tun_set_rx_csum(struct net_device *dev, u32 data)
860{
861 struct tun_struct *tun = netdev_priv(dev);
862 if (data)
863 tun->flags &= ~TUN_NOCHECKSUM;
864 else
865 tun->flags |= TUN_NOCHECKSUM;
866 return 0;
867}
868
Jeff Garzik7282d492006-09-13 14:30:00 -0400869static const struct ethtool_ops tun_ethtool_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 .get_settings = tun_get_settings,
871 .get_drvinfo = tun_get_drvinfo,
872 .get_msglevel = tun_get_msglevel,
873 .set_msglevel = tun_set_msglevel,
874 .get_link = tun_get_link,
875 .get_rx_csum = tun_get_rx_csum,
876 .set_rx_csum = tun_set_rx_csum
877};
878
879static int __init tun_init(void)
880{
881 int ret = 0;
882
883 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
884 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
885
886 ret = misc_register(&tun_miscdev);
887 if (ret)
888 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
889 return ret;
890}
891
892static void tun_cleanup(void)
893{
894 struct tun_struct *tun, *nxt;
895
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400896 misc_deregister(&tun_miscdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897
898 rtnl_lock();
899 list_for_each_entry_safe(tun, nxt, &tun_dev_list, list) {
900 DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
901 unregister_netdevice(tun->dev);
902 }
903 rtnl_unlock();
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400904
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905}
906
907module_init(tun_init);
908module_exit(tun_cleanup);
909MODULE_DESCRIPTION(DRV_DESCRIPTION);
910MODULE_AUTHOR(DRV_COPYRIGHT);
911MODULE_LICENSE("GPL");
912MODULE_ALIAS_MISCDEV(TUN_MINOR);