[PATCH] beginning of 8390 fixes - generic and arm/etherh
[linux-2.6] / drivers / net / tun.c
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  *  Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
22  *    Add TUNSETLINK ioctl to set the link encapsulation
23  *
24  *  Mark Smith <markzzzsmith@yahoo.com.au>
25  *   Use random_ether_addr() for tap MAC address.
26  *
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
37 #define DRV_NAME        "tun"
38 #define DRV_VERSION     "1.6"
39 #define DRV_DESCRIPTION "Universal TUN/TAP device driver"
40 #define DRV_COPYRIGHT   "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
41
42 #include <linux/module.h>
43 #include <linux/errno.h>
44 #include <linux/kernel.h>
45 #include <linux/major.h>
46 #include <linux/slab.h>
47 #include <linux/poll.h>
48 #include <linux/fcntl.h>
49 #include <linux/init.h>
50 #include <linux/skbuff.h>
51 #include <linux/netdevice.h>
52 #include <linux/etherdevice.h>
53 #include <linux/miscdevice.h>
54 #include <linux/ethtool.h>
55 #include <linux/rtnetlink.h>
56 #include <linux/if.h>
57 #include <linux/if_arp.h>
58 #include <linux/if_ether.h>
59 #include <linux/if_tun.h>
60 #include <linux/crc32.h>
61
62 #include <asm/system.h>
63 #include <asm/uaccess.h>
64
65 #ifdef TUN_DEBUG
66 static int debug;
67 #endif
68
69 /* Network device part of the driver */
70
71 static LIST_HEAD(tun_dev_list);
72 static const struct ethtool_ops tun_ethtool_ops;
73
74 /* Net device open. */
75 static int tun_net_open(struct net_device *dev)
76 {
77         netif_start_queue(dev);
78         return 0;
79 }
80
81 /* Net device close. */
82 static int tun_net_close(struct net_device *dev)
83 {
84         netif_stop_queue(dev);
85         return 0;
86 }
87
88 /* Net device start xmit */
89 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
90 {
91         struct tun_struct *tun = netdev_priv(dev);
92
93         DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
94
95         /* Drop packet if interface is not attached */
96         if (!tun->attached)
97                 goto drop;
98
99         /* Packet dropping */
100         if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
101                 if (!(tun->flags & TUN_ONE_QUEUE)) {
102                         /* Normal queueing mode. */
103                         /* Packet scheduler handles dropping of further packets. */
104                         netif_stop_queue(dev);
105
106                         /* We won't see all dropped packets individually, so overrun
107                          * error is more appropriate. */
108                         tun->stats.tx_fifo_errors++;
109                 } else {
110                         /* Single queue mode.
111                          * Driver handles dropping of all packets itself. */
112                         goto drop;
113                 }
114         }
115
116         /* Queue packet */
117         skb_queue_tail(&tun->readq, skb);
118         dev->trans_start = jiffies;
119
120         /* Notify and wake up reader process */
121         if (tun->flags & TUN_FASYNC)
122                 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
123         wake_up_interruptible(&tun->read_wait);
124         return 0;
125
126 drop:
127         tun->stats.tx_dropped++;
128         kfree_skb(skb);
129         return 0;
130 }
131
132 /** Add the specified Ethernet address to this multicast filter. */
133 static void
134 add_multi(u32* filter, const u8* addr)
135 {
136         int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
137         filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
138 }
139
140 /** Remove the specified Ethernet addres from this multicast filter. */
141 static void
142 del_multi(u32* filter, const u8* addr)
143 {
144         int bit_nr = ether_crc(ETH_ALEN, addr) >> 26;
145         filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31));
146 }
147
148 /** Update the list of multicast groups to which the network device belongs.
149  * This list is used to filter packets being sent from the character device to
150  * the network device. */
151 static void
152 tun_net_mclist(struct net_device *dev)
153 {
154         struct tun_struct *tun = netdev_priv(dev);
155         const struct dev_mc_list *mclist;
156         int i;
157         DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n",
158                         dev->name, dev->mc_count);
159         memset(tun->chr_filter, 0, sizeof tun->chr_filter);
160         for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL;
161                         i++, mclist = mclist->next) {
162                 add_multi(tun->net_filter, mclist->dmi_addr);
163                 DBG(KERN_DEBUG "%s: tun_net_mclist: %x:%x:%x:%x:%x:%x\n",
164                                 dev->name,
165                                 mclist->dmi_addr[0], mclist->dmi_addr[1], mclist->dmi_addr[2],
166                                 mclist->dmi_addr[3], mclist->dmi_addr[4], mclist->dmi_addr[5]);
167         }
168 }
169
170 static struct net_device_stats *tun_net_stats(struct net_device *dev)
171 {
172         struct tun_struct *tun = netdev_priv(dev);
173         return &tun->stats;
174 }
175
176 /* Initialize net device. */
177 static void tun_net_init(struct net_device *dev)
178 {
179         struct tun_struct *tun = netdev_priv(dev);
180
181         switch (tun->flags & TUN_TYPE_MASK) {
182         case TUN_TUN_DEV:
183                 /* Point-to-Point TUN Device */
184                 dev->hard_header_len = 0;
185                 dev->addr_len = 0;
186                 dev->mtu = 1500;
187
188                 /* Zero header length */
189                 dev->type = ARPHRD_NONE;
190                 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
191                 dev->tx_queue_len = TUN_READQ_SIZE;  /* We prefer our own queue length */
192                 break;
193
194         case TUN_TAP_DEV:
195                 /* Ethernet TAP Device */
196                 dev->set_multicast_list = tun_net_mclist;
197
198                 ether_setup(dev);
199                 random_ether_addr(dev->dev_addr);
200                 dev->tx_queue_len = TUN_READQ_SIZE;  /* We prefer our own queue length */
201                 break;
202         }
203 }
204
205 /* Character device part */
206
207 /* Poll */
208 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
209 {
210         struct tun_struct *tun = file->private_data;
211         unsigned int mask = POLLOUT | POLLWRNORM;
212
213         if (!tun)
214                 return -EBADFD;
215
216         DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
217
218         poll_wait(file, &tun->read_wait, wait);
219
220         if (!skb_queue_empty(&tun->readq))
221                 mask |= POLLIN | POLLRDNORM;
222
223         return mask;
224 }
225
226 /* Get packet from user space buffer */
227 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
228 {
229         struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
230         struct sk_buff *skb;
231         size_t len = count, align = 0;
232
233         if (!(tun->flags & TUN_NO_PI)) {
234                 if ((len -= sizeof(pi)) > count)
235                         return -EINVAL;
236
237                 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
238                         return -EFAULT;
239         }
240
241         if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV)
242                 align = NET_IP_ALIGN;
243
244         if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
245                 tun->stats.rx_dropped++;
246                 return -ENOMEM;
247         }
248
249         if (align)
250                 skb_reserve(skb, align);
251         if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
252                 tun->stats.rx_dropped++;
253                 kfree_skb(skb);
254                 return -EFAULT;
255         }
256
257         skb->dev = tun->dev;
258         switch (tun->flags & TUN_TYPE_MASK) {
259         case TUN_TUN_DEV:
260                 skb->mac.raw = skb->data;
261                 skb->protocol = pi.proto;
262                 break;
263         case TUN_TAP_DEV:
264                 skb->protocol = eth_type_trans(skb, tun->dev);
265                 break;
266         };
267
268         if (tun->flags & TUN_NOCHECKSUM)
269                 skb->ip_summed = CHECKSUM_UNNECESSARY;
270
271         netif_rx_ni(skb);
272         tun->dev->last_rx = jiffies;
273
274         tun->stats.rx_packets++;
275         tun->stats.rx_bytes += len;
276
277         return count;
278 }
279
280 static inline size_t iov_total(const struct iovec *iv, unsigned long count)
281 {
282         unsigned long i;
283         size_t len;
284
285         for (i = 0, len = 0; i < count; i++)
286                 len += iv[i].iov_len;
287
288         return len;
289 }
290
291 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
292                               unsigned long count, loff_t pos)
293 {
294         struct tun_struct *tun = iocb->ki_filp->private_data;
295
296         if (!tun)
297                 return -EBADFD;
298
299         DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
300
301         return tun_get_user(tun, (struct iovec *) iv, iov_total(iv, count));
302 }
303
304 /* Put packet to the user space buffer */
305 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
306                                        struct sk_buff *skb,
307                                        struct iovec *iv, int len)
308 {
309         struct tun_pi pi = { 0, skb->protocol };
310         ssize_t total = 0;
311
312         if (!(tun->flags & TUN_NO_PI)) {
313                 if ((len -= sizeof(pi)) < 0)
314                         return -EINVAL;
315
316                 if (len < skb->len) {
317                         /* Packet will be striped */
318                         pi.flags |= TUN_PKT_STRIP;
319                 }
320
321                 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
322                         return -EFAULT;
323                 total += sizeof(pi);
324         }
325
326         len = min_t(int, skb->len, len);
327
328         skb_copy_datagram_iovec(skb, 0, iv, len);
329         total += len;
330
331         tun->stats.tx_packets++;
332         tun->stats.tx_bytes += len;
333
334         return total;
335 }
336
337 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
338                             unsigned long count, loff_t pos)
339 {
340         struct file *file = iocb->ki_filp;
341         struct tun_struct *tun = file->private_data;
342         DECLARE_WAITQUEUE(wait, current);
343         struct sk_buff *skb;
344         ssize_t len, ret = 0;
345
346         if (!tun)
347                 return -EBADFD;
348
349         DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
350
351         len = iov_total(iv, count);
352         if (len < 0)
353                 return -EINVAL;
354
355         add_wait_queue(&tun->read_wait, &wait);
356         while (len) {
357                 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
358                 u8 addr[ ETH_ALEN];
359                 int bit_nr;
360
361                 current->state = TASK_INTERRUPTIBLE;
362
363                 /* Read frames from the queue */
364                 if (!(skb=skb_dequeue(&tun->readq))) {
365                         if (file->f_flags & O_NONBLOCK) {
366                                 ret = -EAGAIN;
367                                 break;
368                         }
369                         if (signal_pending(current)) {
370                                 ret = -ERESTARTSYS;
371                                 break;
372                         }
373
374                         /* Nothing to read, let's sleep */
375                         schedule();
376                         continue;
377                 }
378                 netif_wake_queue(tun->dev);
379
380                 /** Decide whether to accept this packet. This code is designed to
381                  * behave identically to an Ethernet interface. Accept the packet if
382                  * - we are promiscuous.
383                  * - the packet is addressed to us.
384                  * - the packet is broadcast.
385                  * - the packet is multicast and
386                  *   - we are multicast promiscous.
387                  *   - we belong to the multicast group.
388                  */
389                 memcpy(addr, skb->data,
390                        min_t(size_t, sizeof addr, skb->len));
391                 bit_nr = ether_crc(sizeof addr, addr) >> 26;
392                 if ((tun->if_flags & IFF_PROMISC) ||
393                                 memcmp(addr, tun->dev_addr, sizeof addr) == 0 ||
394                                 memcmp(addr, ones, sizeof addr) == 0 ||
395                                 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) ||
396                                   (addr[0] == 0x33 && addr[1] == 0x33)) &&
397                                  ((tun->if_flags & IFF_ALLMULTI) ||
398                                   (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) {
399                         DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %x:%x:%x:%x:%x:%x\n",
400                                         tun->dev->name, addr[0], addr[1], addr[2],
401                                         addr[3], addr[4], addr[5]);
402                         ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
403                         kfree_skb(skb);
404                         break;
405                 } else {
406                         DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %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                         kfree_skb(skb);
410                         continue;
411                 }
412         }
413
414         current->state = TASK_RUNNING;
415         remove_wait_queue(&tun->read_wait, &wait);
416
417         return ret;
418 }
419
420 static void tun_setup(struct net_device *dev)
421 {
422         struct tun_struct *tun = netdev_priv(dev);
423
424         skb_queue_head_init(&tun->readq);
425         init_waitqueue_head(&tun->read_wait);
426
427         tun->owner = -1;
428
429         SET_MODULE_OWNER(dev);
430         dev->open = tun_net_open;
431         dev->hard_start_xmit = tun_net_xmit;
432         dev->stop = tun_net_close;
433         dev->get_stats = tun_net_stats;
434         dev->ethtool_ops = &tun_ethtool_ops;
435         dev->destructor = free_netdev;
436 }
437
438 static struct tun_struct *tun_get_by_name(const char *name)
439 {
440         struct tun_struct *tun;
441
442         ASSERT_RTNL();
443         list_for_each_entry(tun, &tun_dev_list, list) {
444                 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
445                     return tun;
446         }
447
448         return NULL;
449 }
450
451 static int tun_set_iff(struct file *file, struct ifreq *ifr)
452 {
453         struct tun_struct *tun;
454         struct net_device *dev;
455         int err;
456
457         tun = tun_get_by_name(ifr->ifr_name);
458         if (tun) {
459                 if (tun->attached)
460                         return -EBUSY;
461
462                 /* Check permissions */
463                 if (tun->owner != -1 &&
464                     current->euid != tun->owner && !capable(CAP_NET_ADMIN))
465                         return -EPERM;
466         }
467         else if (__dev_get_by_name(ifr->ifr_name))
468                 return -EINVAL;
469         else {
470                 char *name;
471                 unsigned long flags = 0;
472
473                 err = -EINVAL;
474
475                 if (!capable(CAP_NET_ADMIN))
476                         return -EPERM;
477
478                 /* Set dev type */
479                 if (ifr->ifr_flags & IFF_TUN) {
480                         /* TUN device */
481                         flags |= TUN_TUN_DEV;
482                         name = "tun%d";
483                 } else if (ifr->ifr_flags & IFF_TAP) {
484                         /* TAP device */
485                         flags |= TUN_TAP_DEV;
486                         name = "tap%d";
487                 } else
488                         goto failed;
489
490                 if (*ifr->ifr_name)
491                         name = ifr->ifr_name;
492
493                 dev = alloc_netdev(sizeof(struct tun_struct), name,
494                                    tun_setup);
495                 if (!dev)
496                         return -ENOMEM;
497
498                 tun = netdev_priv(dev);
499                 tun->dev = dev;
500                 tun->flags = flags;
501                 /* Be promiscuous by default to maintain previous behaviour. */
502                 tun->if_flags = IFF_PROMISC;
503                 /* Generate random Ethernet address. */
504                 *(u16 *)tun->dev_addr = htons(0x00FF);
505                 get_random_bytes(tun->dev_addr + sizeof(u16), 4);
506                 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
507
508                 tun_net_init(dev);
509
510                 if (strchr(dev->name, '%')) {
511                         err = dev_alloc_name(dev, dev->name);
512                         if (err < 0)
513                                 goto err_free_dev;
514                 }
515
516                 err = register_netdevice(tun->dev);
517                 if (err < 0)
518                         goto err_free_dev;
519
520                 list_add(&tun->list, &tun_dev_list);
521         }
522
523         DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
524
525         if (ifr->ifr_flags & IFF_NO_PI)
526                 tun->flags |= TUN_NO_PI;
527
528         if (ifr->ifr_flags & IFF_ONE_QUEUE)
529                 tun->flags |= TUN_ONE_QUEUE;
530
531         file->private_data = tun;
532         tun->attached = 1;
533
534         strcpy(ifr->ifr_name, tun->dev->name);
535         return 0;
536
537  err_free_dev:
538         free_netdev(dev);
539  failed:
540         return err;
541 }
542
543 static int tun_chr_ioctl(struct inode *inode, struct file *file,
544                          unsigned int cmd, unsigned long arg)
545 {
546         struct tun_struct *tun = file->private_data;
547         void __user* argp = (void __user*)arg;
548         struct ifreq ifr;
549
550         if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
551                 if (copy_from_user(&ifr, argp, sizeof ifr))
552                         return -EFAULT;
553
554         if (cmd == TUNSETIFF && !tun) {
555                 int err;
556
557                 ifr.ifr_name[IFNAMSIZ-1] = '\0';
558
559                 rtnl_lock();
560                 err = tun_set_iff(file, &ifr);
561                 rtnl_unlock();
562
563                 if (err)
564                         return err;
565
566                 if (copy_to_user(argp, &ifr, sizeof(ifr)))
567                         return -EFAULT;
568                 return 0;
569         }
570
571         if (!tun)
572                 return -EBADFD;
573
574         DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
575
576         switch (cmd) {
577         case TUNSETNOCSUM:
578                 /* Disable/Enable checksum */
579                 if (arg)
580                         tun->flags |= TUN_NOCHECKSUM;
581                 else
582                         tun->flags &= ~TUN_NOCHECKSUM;
583
584                 DBG(KERN_INFO "%s: checksum %s\n",
585                     tun->dev->name, arg ? "disabled" : "enabled");
586                 break;
587
588         case TUNSETPERSIST:
589                 /* Disable/Enable persist mode */
590                 if (arg)
591                         tun->flags |= TUN_PERSIST;
592                 else
593                         tun->flags &= ~TUN_PERSIST;
594
595                 DBG(KERN_INFO "%s: persist %s\n",
596                     tun->dev->name, arg ? "disabled" : "enabled");
597                 break;
598
599         case TUNSETOWNER:
600                 /* Set owner of the device */
601                 tun->owner = (uid_t) arg;
602
603                 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
604                 break;
605
606         case TUNSETLINK:
607                 /* Only allow setting the type when the interface is down */
608                 if (tun->dev->flags & IFF_UP) {
609                         DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
610                                 tun->dev->name);
611                         return -EBUSY;
612                 } else {
613                         tun->dev->type = (int) arg;
614                         DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
615                 }
616                 break;
617
618 #ifdef TUN_DEBUG
619         case TUNSETDEBUG:
620                 tun->debug = arg;
621                 break;
622 #endif
623
624         case SIOCGIFFLAGS:
625                 ifr.ifr_flags = tun->if_flags;
626                 if (copy_to_user( argp, &ifr, sizeof ifr))
627                         return -EFAULT;
628                 return 0;
629
630         case SIOCSIFFLAGS:
631                 /** Set the character device's interface flags. Currently only
632                  * IFF_PROMISC and IFF_ALLMULTI are used. */
633                 tun->if_flags = ifr.ifr_flags;
634                 DBG(KERN_INFO "%s: interface flags 0x%lx\n",
635                                 tun->dev->name, tun->if_flags);
636                 return 0;
637
638         case SIOCGIFHWADDR:
639                 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
640                                 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
641                 if (copy_to_user( argp, &ifr, sizeof ifr))
642                         return -EFAULT;
643                 return 0;
644
645         case SIOCSIFHWADDR:
646                 /** Set the character device's hardware address. This is used when
647                  * filtering packets being sent from the network device to the character
648                  * device. */
649                 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
650                                 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
651                 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
652                                 tun->dev->name,
653                                 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
654                                 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
655                 return 0;
656
657         case SIOCADDMULTI:
658                 /** Add the specified group to the character device's multicast filter
659                  * list. */
660                 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
661                 DBG(KERN_DEBUG "%s: add multi: %x:%x:%x:%x:%x:%x\n",
662                                 tun->dev->name,
663                                 (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1],
664                                 (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3],
665                                 (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]);
666                 return 0;
667
668         case SIOCDELMULTI:
669                 /** Remove the specified group from the character device's multicast
670                  * filter list. */
671                 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
672                 DBG(KERN_DEBUG "%s: del multi: %x:%x:%x:%x:%x:%x\n",
673                                 tun->dev->name,
674                                 (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1],
675                                 (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3],
676                                 (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]);
677                 return 0;
678
679         default:
680                 return -EINVAL;
681         };
682
683         return 0;
684 }
685
686 static int tun_chr_fasync(int fd, struct file *file, int on)
687 {
688         struct tun_struct *tun = file->private_data;
689         int ret;
690
691         if (!tun)
692                 return -EBADFD;
693
694         DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
695
696         if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
697                 return ret;
698
699         if (on) {
700                 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
701                 if (ret)
702                         return ret;
703                 tun->flags |= TUN_FASYNC;
704         } else
705                 tun->flags &= ~TUN_FASYNC;
706
707         return 0;
708 }
709
710 static int tun_chr_open(struct inode *inode, struct file * file)
711 {
712         DBG1(KERN_INFO "tunX: tun_chr_open\n");
713         file->private_data = NULL;
714         return 0;
715 }
716
717 static int tun_chr_close(struct inode *inode, struct file *file)
718 {
719         struct tun_struct *tun = file->private_data;
720
721         if (!tun)
722                 return 0;
723
724         DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
725
726         tun_chr_fasync(-1, file, 0);
727
728         rtnl_lock();
729
730         /* Detach from net device */
731         file->private_data = NULL;
732         tun->attached = 0;
733
734         /* Drop read queue */
735         skb_queue_purge(&tun->readq);
736
737         if (!(tun->flags & TUN_PERSIST)) {
738                 list_del(&tun->list);
739                 unregister_netdevice(tun->dev);
740         }
741
742         rtnl_unlock();
743
744         return 0;
745 }
746
747 static struct file_operations tun_fops = {
748         .owner  = THIS_MODULE,
749         .llseek = no_llseek,
750         .read  = do_sync_read,
751         .aio_read  = tun_chr_aio_read,
752         .write = do_sync_write,
753         .aio_write = tun_chr_aio_write,
754         .poll   = tun_chr_poll,
755         .ioctl  = tun_chr_ioctl,
756         .open   = tun_chr_open,
757         .release = tun_chr_close,
758         .fasync = tun_chr_fasync
759 };
760
761 static struct miscdevice tun_miscdev = {
762         .minor = TUN_MINOR,
763         .name = "tun",
764         .fops = &tun_fops,
765 };
766
767 /* ethtool interface */
768
769 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
770 {
771         cmd->supported          = 0;
772         cmd->advertising        = 0;
773         cmd->speed              = SPEED_10;
774         cmd->duplex             = DUPLEX_FULL;
775         cmd->port               = PORT_TP;
776         cmd->phy_address        = 0;
777         cmd->transceiver        = XCVR_INTERNAL;
778         cmd->autoneg            = AUTONEG_DISABLE;
779         cmd->maxtxpkt           = 0;
780         cmd->maxrxpkt           = 0;
781         return 0;
782 }
783
784 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
785 {
786         struct tun_struct *tun = netdev_priv(dev);
787
788         strcpy(info->driver, DRV_NAME);
789         strcpy(info->version, DRV_VERSION);
790         strcpy(info->fw_version, "N/A");
791
792         switch (tun->flags & TUN_TYPE_MASK) {
793         case TUN_TUN_DEV:
794                 strcpy(info->bus_info, "tun");
795                 break;
796         case TUN_TAP_DEV:
797                 strcpy(info->bus_info, "tap");
798                 break;
799         }
800 }
801
802 static u32 tun_get_msglevel(struct net_device *dev)
803 {
804 #ifdef TUN_DEBUG
805         struct tun_struct *tun = netdev_priv(dev);
806         return tun->debug;
807 #else
808         return -EOPNOTSUPP;
809 #endif
810 }
811
812 static void tun_set_msglevel(struct net_device *dev, u32 value)
813 {
814 #ifdef TUN_DEBUG
815         struct tun_struct *tun = netdev_priv(dev);
816         tun->debug = value;
817 #endif
818 }
819
820 static u32 tun_get_link(struct net_device *dev)
821 {
822         struct tun_struct *tun = netdev_priv(dev);
823         return tun->attached;
824 }
825
826 static u32 tun_get_rx_csum(struct net_device *dev)
827 {
828         struct tun_struct *tun = netdev_priv(dev);
829         return (tun->flags & TUN_NOCHECKSUM) == 0;
830 }
831
832 static int tun_set_rx_csum(struct net_device *dev, u32 data)
833 {
834         struct tun_struct *tun = netdev_priv(dev);
835         if (data)
836                 tun->flags &= ~TUN_NOCHECKSUM;
837         else
838                 tun->flags |= TUN_NOCHECKSUM;
839         return 0;
840 }
841
842 static const struct ethtool_ops tun_ethtool_ops = {
843         .get_settings   = tun_get_settings,
844         .get_drvinfo    = tun_get_drvinfo,
845         .get_msglevel   = tun_get_msglevel,
846         .set_msglevel   = tun_set_msglevel,
847         .get_link       = tun_get_link,
848         .get_rx_csum    = tun_get_rx_csum,
849         .set_rx_csum    = tun_set_rx_csum
850 };
851
852 static int __init tun_init(void)
853 {
854         int ret = 0;
855
856         printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
857         printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
858
859         ret = misc_register(&tun_miscdev);
860         if (ret)
861                 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
862         return ret;
863 }
864
865 static void tun_cleanup(void)
866 {
867         struct tun_struct *tun, *nxt;
868
869         misc_deregister(&tun_miscdev);
870
871         rtnl_lock();
872         list_for_each_entry_safe(tun, nxt, &tun_dev_list, list) {
873                 DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
874                 unregister_netdevice(tun->dev);
875         }
876         rtnl_unlock();
877
878 }
879
880 module_init(tun_init);
881 module_exit(tun_cleanup);
882 MODULE_DESCRIPTION(DRV_DESCRIPTION);
883 MODULE_AUTHOR(DRV_COPYRIGHT);
884 MODULE_LICENSE("GPL");
885 MODULE_ALIAS_MISCDEV(TUN_MINOR);