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i386: move kernel/cpu/mtrr
[linux-2.6/kvm.git] / drivers / net / tun.c
blob62b2b3005019c90865ef0f019f16d8d2607089f0
1 /*
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 *
21 * 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 *
25 * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
26 * Add TUNSETLINK ioctl to set the link encapsulation
27 *
28 * 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
46 #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>
65
66 #include <asm/system.h>
67 #include <asm/uaccess.h>
68
69 #ifdef TUN_DEBUG
70 static int debug;
71 #endif
72
73 /* Network device part of the driver */
74
75 static LIST_HEAD(tun_dev_list);
76 static const struct ethtool_ops tun_ethtool_ops;
77
78 /* Net device open. */
79 static int tun_net_open(struct net_device *dev)
80 {
81 netif_start_queue(dev);
82 return 0;
83 }
84
85 /* Net device close. */
86 static int tun_net_close(struct net_device *dev)
87 {
88 netif_stop_queue(dev);
89 return 0;
90 }
91
92 /* Net device start xmit */
93 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
94 {
95 struct tun_struct *tun = netdev_priv(dev);
96
97 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
98
99 /* Drop packet if interface is not attached */
100 if (!tun->attached)
101 goto drop;
102
103 /* Packet dropping */
104 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
105 if (!(tun->flags & TUN_ONE_QUEUE)) {
106 /* Normal queueing mode. */
107 /* Packet scheduler handles dropping of further packets. */
108 netif_stop_queue(dev);
109
110 /* We won't see all dropped packets individually, so overrun
111 * error is more appropriate. */
112 tun->stats.tx_fifo_errors++;
113 } else {
114 /* Single queue mode.
115 * Driver handles dropping of all packets itself. */
116 goto drop;
117 }
118 }
119
120 /* Queue packet */
121 skb_queue_tail(&tun->readq, skb);
122 dev->trans_start = jiffies;
123
124 /* Notify and wake up reader process */
125 if (tun->flags & TUN_FASYNC)
126 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
127 wake_up_interruptible(&tun->read_wait);
128 return 0;
129
130 drop:
131 tun->stats.tx_dropped++;
132 kfree_skb(skb);
133 return 0;
134 }
135
136 /** Add the specified Ethernet address to this multicast filter. */
137 static void
138 add_multi(u32* filter, const u8* addr)
139 {
140 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
141 filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
142 }
143
144 /** Remove the specified Ethernet addres from this multicast filter. */
145 static void
146 del_multi(u32* filter, const u8* addr)
147 {
148 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
149 filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31));
150 }
151
152 /** Update the list of multicast groups to which the network device belongs.
153 * This list is used to filter packets being sent from the character device to
154 * the network device. */
155 static void
156 tun_net_mclist(struct net_device *dev)
157 {
158 struct tun_struct *tun = netdev_priv(dev);
159 const struct dev_mc_list *mclist;
160 int i;
161 DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n",
162 dev->name, dev->mc_count);
163 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
164 for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL;
165 i++, mclist = mclist->next) {
166 add_multi(tun->net_filter, mclist->dmi_addr);
167 DBG(KERN_DEBUG "%s: tun_net_mclist: %x:%x:%x:%x:%x:%x\n",
168 dev->name,
169 mclist->dmi_addr[0], mclist->dmi_addr[1], mclist->dmi_addr[2],
170 mclist->dmi_addr[3], mclist->dmi_addr[4], mclist->dmi_addr[5]);
171 }
172 }
173
174 static struct net_device_stats *tun_net_stats(struct net_device *dev)
175 {
176 struct tun_struct *tun = netdev_priv(dev);
177 return &tun->stats;
178 }
179
180 /* Initialize net device. */
181 static void tun_net_init(struct net_device *dev)
182 {
183 struct tun_struct *tun = netdev_priv(dev);
184
185 switch (tun->flags & TUN_TYPE_MASK) {
186 case TUN_TUN_DEV:
187 /* Point-to-Point TUN Device */
188 dev->hard_header_len = 0;
189 dev->addr_len = 0;
190 dev->mtu = 1500;
191
192 /* Zero header length */
193 dev->type = ARPHRD_NONE;
194 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
195 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
196 break;
197
198 case TUN_TAP_DEV:
199 /* Ethernet TAP Device */
200 dev->set_multicast_list = tun_net_mclist;
201
202 ether_setup(dev);
203
204 /* random address already created for us by tun_set_iff, use it */
205 memcpy(dev->dev_addr, tun->dev_addr, min(sizeof(tun->dev_addr), sizeof(dev->dev_addr)) );
206
207 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
208 break;
209 }
210 }
211
212 /* Character device part */
213
214 /* Poll */
215 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
216 {
217 struct tun_struct *tun = file->private_data;
218 unsigned int mask = POLLOUT | POLLWRNORM;
219
220 if (!tun)
221 return -EBADFD;
222
223 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
224
225 poll_wait(file, &tun->read_wait, wait);
226
227 if (!skb_queue_empty(&tun->readq))
228 mask |= POLLIN | POLLRDNORM;
229
230 return mask;
231 }
232
233 /* Get packet from user space buffer */
234 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
235 {
236 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
237 struct sk_buff *skb;
238 size_t len = count, align = 0;
239
240 if (!(tun->flags & TUN_NO_PI)) {
241 if ((len -= sizeof(pi)) > count)
242 return -EINVAL;
243
244 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
245 return -EFAULT;
246 }
247
248 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV)
249 align = NET_IP_ALIGN;
250
251 if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
252 tun->stats.rx_dropped++;
253 return -ENOMEM;
254 }
255
256 if (align)
257 skb_reserve(skb, align);
258 if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
259 tun->stats.rx_dropped++;
260 kfree_skb(skb);
261 return -EFAULT;
262 }
263
264 switch (tun->flags & TUN_TYPE_MASK) {
265 case TUN_TUN_DEV:
266 skb_reset_mac_header(skb);
267 skb->protocol = pi.proto;
268 skb->dev = tun->dev;
269 break;
270 case TUN_TAP_DEV:
271 skb->protocol = eth_type_trans(skb, tun->dev);
272 break;
273 };
274
275 if (tun->flags & TUN_NOCHECKSUM)
276 skb->ip_summed = CHECKSUM_UNNECESSARY;
277
278 netif_rx_ni(skb);
279 tun->dev->last_rx = jiffies;
280
281 tun->stats.rx_packets++;
282 tun->stats.rx_bytes += len;
283
284 return count;
285 }
286
287 static inline size_t iov_total(const struct iovec *iv, unsigned long count)
288 {
289 unsigned long i;
290 size_t len;
291
292 for (i = 0, len = 0; i < count; i++)
293 len += iv[i].iov_len;
294
295 return len;
296 }
297
298 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
299 unsigned long count, loff_t pos)
300 {
301 struct tun_struct *tun = iocb->ki_filp->private_data;
302
303 if (!tun)
304 return -EBADFD;
305
306 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
307
308 return tun_get_user(tun, (struct iovec *) iv, iov_total(iv, count));
309 }
310
311 /* Put packet to the user space buffer */
312 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
313 struct sk_buff *skb,
314 struct iovec *iv, int len)
315 {
316 struct tun_pi pi = { 0, skb->protocol };
317 ssize_t total = 0;
318
319 if (!(tun->flags & TUN_NO_PI)) {
320 if ((len -= sizeof(pi)) < 0)
321 return -EINVAL;
322
323 if (len < skb->len) {
324 /* Packet will be striped */
325 pi.flags |= TUN_PKT_STRIP;
326 }
327
328 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
329 return -EFAULT;
330 total += sizeof(pi);
331 }
332
333 len = min_t(int, skb->len, len);
334
335 skb_copy_datagram_iovec(skb, 0, iv, len);
336 total += len;
337
338 tun->stats.tx_packets++;
339 tun->stats.tx_bytes += len;
340
341 return total;
342 }
343
344 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
345 unsigned long count, loff_t pos)
346 {
347 struct file *file = iocb->ki_filp;
348 struct tun_struct *tun = file->private_data;
349 DECLARE_WAITQUEUE(wait, current);
350 struct sk_buff *skb;
351 ssize_t len, ret = 0;
352
353 if (!tun)
354 return -EBADFD;
355
356 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
357
358 len = iov_total(iv, count);
359 if (len < 0)
360 return -EINVAL;
361
362 add_wait_queue(&tun->read_wait, &wait);
363 while (len) {
364 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
365 u8 addr[ ETH_ALEN];
366 int bit_nr;
367
368 current->state = TASK_INTERRUPTIBLE;
369
370 /* Read frames from the queue */
371 if (!(skb=skb_dequeue(&tun->readq))) {
372 if (file->f_flags & O_NONBLOCK) {
373 ret = -EAGAIN;
374 break;
375 }
376 if (signal_pending(current)) {
377 ret = -ERESTARTSYS;
378 break;
379 }
380
381 /* Nothing to read, let's sleep */
382 schedule();
383 continue;
384 }
385 netif_wake_queue(tun->dev);
386
387 /** Decide whether to accept this packet. This code is designed to
388 * behave identically to an Ethernet interface. Accept the packet if
389 * - we are promiscuous.
390 * - the packet is addressed to us.
391 * - the packet is broadcast.
392 * - the packet is multicast and
393 * - we are multicast promiscous.
394 * - we belong to the multicast group.
395 */
396 skb_copy_from_linear_data(skb, addr, min_t(size_t, sizeof addr,
397 skb->len));
398 bit_nr = ether_crc(sizeof addr, addr) >> 26;
399 if ((tun->if_flags & IFF_PROMISC) ||
400 memcmp(addr, tun->dev_addr, sizeof addr) == 0 ||
401 memcmp(addr, ones, sizeof addr) == 0 ||
402 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) ||
403 (addr[0] == 0x33 && addr[1] == 0x33)) &&
404 ((tun->if_flags & IFF_ALLMULTI) ||
405 (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) {
406 DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %x:%x:%x:%x:%x:%x\n",
407 tun->dev->name, addr[0], addr[1], addr[2],
408 addr[3], addr[4], addr[5]);
409 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
410 kfree_skb(skb);
411 break;
412 } else {
413 DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %x:%x:%x:%x:%x:%x\n",
414 tun->dev->name, addr[0], addr[1], addr[2],
415 addr[3], addr[4], addr[5]);
416 kfree_skb(skb);
417 continue;
418 }
419 }
420
421 current->state = TASK_RUNNING;
422 remove_wait_queue(&tun->read_wait, &wait);
423
424 return ret;
425 }
426
427 static void tun_setup(struct net_device *dev)
428 {
429 struct tun_struct *tun = netdev_priv(dev);
430
431 skb_queue_head_init(&tun->readq);
432 init_waitqueue_head(&tun->read_wait);
433
434 tun->owner = -1;
435 tun->group = -1;
436
437 SET_MODULE_OWNER(dev);
438 dev->open = tun_net_open;
439 dev->hard_start_xmit = tun_net_xmit;
440 dev->stop = tun_net_close;
441 dev->get_stats = tun_net_stats;
442 dev->ethtool_ops = &tun_ethtool_ops;
443 dev->destructor = free_netdev;
444 }
445
446 static struct tun_struct *tun_get_by_name(const char *name)
447 {
448 struct tun_struct *tun;
449
450 ASSERT_RTNL();
451 list_for_each_entry(tun, &tun_dev_list, list) {
452 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
453 return tun;
454 }
455
456 return NULL;
457 }
458
459 static int tun_set_iff(struct file *file, struct ifreq *ifr)
460 {
461 struct tun_struct *tun;
462 struct net_device *dev;
463 int err;
464
465 tun = tun_get_by_name(ifr->ifr_name);
466 if (tun) {
467 if (tun->attached)
468 return -EBUSY;
469
470 /* Check permissions */
471 if (((tun->owner != -1 &&
472 current->euid != tun->owner) ||
473 (tun->group != -1 &&
474 current->egid != tun->group)) &&
475 !capable(CAP_NET_ADMIN))
476 return -EPERM;
477 }
478 else if (__dev_get_by_name(ifr->ifr_name))
479 return -EINVAL;
480 else {
481 char *name;
482 unsigned long flags = 0;
483
484 err = -EINVAL;
485
486 if (!capable(CAP_NET_ADMIN))
487 return -EPERM;
488
489 /* Set dev type */
490 if (ifr->ifr_flags & IFF_TUN) {
491 /* TUN device */
492 flags |= TUN_TUN_DEV;
493 name = "tun%d";
494 } else if (ifr->ifr_flags & IFF_TAP) {
495 /* TAP device */
496 flags |= TUN_TAP_DEV;
497 name = "tap%d";
498 } else
499 goto failed;
500
501 if (*ifr->ifr_name)
502 name = ifr->ifr_name;
503
504 dev = alloc_netdev(sizeof(struct tun_struct), name,
505 tun_setup);
506 if (!dev)
507 return -ENOMEM;
508
509 tun = netdev_priv(dev);
510 tun->dev = dev;
511 tun->flags = flags;
512 /* Be promiscuous by default to maintain previous behaviour. */
513 tun->if_flags = IFF_PROMISC;
514 /* Generate random Ethernet address. */
515 *(u16 *)tun->dev_addr = htons(0x00FF);
516 get_random_bytes(tun->dev_addr + sizeof(u16), 4);
517 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
518
519 tun_net_init(dev);
520
521 if (strchr(dev->name, '%')) {
522 err = dev_alloc_name(dev, dev->name);
523 if (err < 0)
524 goto err_free_dev;
525 }
526
527 err = register_netdevice(tun->dev);
528 if (err < 0)
529 goto err_free_dev;
530
531 list_add(&tun->list, &tun_dev_list);
532 }
533
534 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
535
536 if (ifr->ifr_flags & IFF_NO_PI)
537 tun->flags |= TUN_NO_PI;
538
539 if (ifr->ifr_flags & IFF_ONE_QUEUE)
540 tun->flags |= TUN_ONE_QUEUE;
541
542 file->private_data = tun;
543 tun->attached = 1;
544
545 strcpy(ifr->ifr_name, tun->dev->name);
546 return 0;
547
548 err_free_dev:
549 free_netdev(dev);
550 failed:
551 return err;
552 }
553
554 static int tun_chr_ioctl(struct inode *inode, struct file *file,
555 unsigned int cmd, unsigned long arg)
556 {
557 struct tun_struct *tun = file->private_data;
558 void __user* argp = (void __user*)arg;
559 struct ifreq ifr;
560
561 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
562 if (copy_from_user(&ifr, argp, sizeof ifr))
563 return -EFAULT;
564
565 if (cmd == TUNSETIFF && !tun) {
566 int err;
567
568 ifr.ifr_name[IFNAMSIZ-1] = '\0';
569
570 rtnl_lock();
571 err = tun_set_iff(file, &ifr);
572 rtnl_unlock();
573
574 if (err)
575 return err;
576
577 if (copy_to_user(argp, &ifr, sizeof(ifr)))
578 return -EFAULT;
579 return 0;
580 }
581
582 if (!tun)
583 return -EBADFD;
584
585 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
586
587 switch (cmd) {
588 case TUNSETNOCSUM:
589 /* Disable/Enable checksum */
590 if (arg)
591 tun->flags |= TUN_NOCHECKSUM;
592 else
593 tun->flags &= ~TUN_NOCHECKSUM;
594
595 DBG(KERN_INFO "%s: checksum %s\n",
596 tun->dev->name, arg ? "disabled" : "enabled");
597 break;
598
599 case TUNSETPERSIST:
600 /* Disable/Enable persist mode */
601 if (arg)
602 tun->flags |= TUN_PERSIST;
603 else
604 tun->flags &= ~TUN_PERSIST;
605
606 DBG(KERN_INFO "%s: persist %s\n",
607 tun->dev->name, arg ? "disabled" : "enabled");
608 break;
609
610 case TUNSETOWNER:
611 /* Set owner of the device */
612 tun->owner = (uid_t) arg;
613
614 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
615 break;
616
617 case TUNSETGROUP:
618 /* Set group of the device */
619 tun->group= (gid_t) arg;
620
621 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
622 break;
623
624 case TUNSETLINK:
625 /* Only allow setting the type when the interface is down */
626 if (tun->dev->flags & IFF_UP) {
627 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
628 tun->dev->name);
629 return -EBUSY;
630 } else {
631 tun->dev->type = (int) arg;
632 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
633 }
634 break;
635
636 #ifdef TUN_DEBUG
637 case TUNSETDEBUG:
638 tun->debug = arg;
639 break;
640 #endif
641
642 case SIOCGIFFLAGS:
643 ifr.ifr_flags = tun->if_flags;
644 if (copy_to_user( argp, &ifr, sizeof ifr))
645 return -EFAULT;
646 return 0;
647
648 case SIOCSIFFLAGS:
649 /** Set the character device's interface flags. Currently only
650 * IFF_PROMISC and IFF_ALLMULTI are used. */
651 tun->if_flags = ifr.ifr_flags;
652 DBG(KERN_INFO "%s: interface flags 0x%lx\n",
653 tun->dev->name, tun->if_flags);
654 return 0;
655
656 case SIOCGIFHWADDR:
657 /* Note: the actual net device's address may be different */
658 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
659 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
660 if (copy_to_user( argp, &ifr, sizeof ifr))
661 return -EFAULT;
662 return 0;
663
664 case SIOCSIFHWADDR:
665 {
666 /* try to set the actual net device's hw address */
667 int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
668
669 if (ret == 0) {
670 /** Set the character device's hardware address. This is used when
671 * filtering packets being sent from the network device to the character
672 * device. */
673 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
674 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
675 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
676 tun->dev->name,
677 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
678 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
679 }
680
681 return ret;
682 }
683
684 case SIOCADDMULTI:
685 /** Add the specified group to the character device's multicast filter
686 * list. */
687 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
688 DBG(KERN_DEBUG "%s: add multi: %x:%x:%x:%x:%x:%x\n",
689 tun->dev->name,
690 (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1],
691 (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3],
692 (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]);
693 return 0;
694
695 case SIOCDELMULTI:
696 /** Remove the specified group from the character device's multicast
697 * filter list. */
698 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
699 DBG(KERN_DEBUG "%s: del multi: %x:%x:%x:%x:%x:%x\n",
700 tun->dev->name,
701 (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1],
702 (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3],
703 (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]);
704 return 0;
705
706 default:
707 return -EINVAL;
708 };
709
710 return 0;
711 }
712
713 static 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)
724 return ret;
725
726 if (on) {
727 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
728 if (ret)
729 return ret;
730 tun->flags |= TUN_FASYNC;
731 } else
732 tun->flags &= ~TUN_FASYNC;
733
734 return 0;
735 }
736
737 static 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
744 static 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
774 static const struct file_operations tun_fops = {
775 .owner = THIS_MODULE,
776 .llseek = no_llseek,
777 .read = do_sync_read,
778 .aio_read = tun_chr_aio_read,
779 .write = do_sync_write,
780 .aio_write = tun_chr_aio_write,
781 .poll = tun_chr_poll,
782 .ioctl = tun_chr_ioctl,
783 .open = tun_chr_open,
784 .release = tun_chr_close,
785 .fasync = tun_chr_fasync
786 };
787
788 static struct miscdevice tun_miscdev = {
789 .minor = TUN_MINOR,
790 .name = "tun",
791 .fops = &tun_fops,
792 };
793
794 /* ethtool interface */
795
796 static 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
811 static 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
829 static 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
839 static 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
847 static u32 tun_get_link(struct net_device *dev)
848 {
849 struct tun_struct *tun = netdev_priv(dev);
850 return tun->attached;
851 }
852
853 static 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
859 static 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
869 static const struct ethtool_ops tun_ethtool_ops = {
870 .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
879 static 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
892 static void tun_cleanup(void)
893 {
894 struct tun_struct *tun, *nxt;
895
896 misc_deregister(&tun_miscdev);
897
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();
904
905 }
906
907 module_init(tun_init);
908 module_exit(tun_cleanup);
909 MODULE_DESCRIPTION(DRV_DESCRIPTION);
910 MODULE_AUTHOR(DRV_COPYRIGHT);
911 MODULE_LICENSE("GPL");
912 MODULE_ALIAS_MISCDEV(TUN_MINOR);
kernel-based virtual machine