[PATCH] libertas: Purge non-mesh ioctls
[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  *  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
436         SET_MODULE_OWNER(dev);
437         dev->open = tun_net_open;
438         dev->hard_start_xmit = tun_net_xmit;
439         dev->stop = tun_net_close;
440         dev->get_stats = tun_net_stats;
441         dev->ethtool_ops = &tun_ethtool_ops;
442         dev->destructor = free_netdev;
443 }
444
445 static struct tun_struct *tun_get_by_name(const char *name)
446 {
447         struct tun_struct *tun;
448
449         ASSERT_RTNL();
450         list_for_each_entry(tun, &tun_dev_list, list) {
451                 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
452                     return tun;
453         }
454
455         return NULL;
456 }
457
458 static int tun_set_iff(struct file *file, struct ifreq *ifr)
459 {
460         struct tun_struct *tun;
461         struct net_device *dev;
462         int err;
463
464         tun = tun_get_by_name(ifr->ifr_name);
465         if (tun) {
466                 if (tun->attached)
467                         return -EBUSY;
468
469                 /* Check permissions */
470                 if (tun->owner != -1 &&
471                     current->euid != tun->owner && !capable(CAP_NET_ADMIN))
472                         return -EPERM;
473         }
474         else if (__dev_get_by_name(ifr->ifr_name))
475                 return -EINVAL;
476         else {
477                 char *name;
478                 unsigned long flags = 0;
479
480                 err = -EINVAL;
481
482                 if (!capable(CAP_NET_ADMIN))
483                         return -EPERM;
484
485                 /* Set dev type */
486                 if (ifr->ifr_flags & IFF_TUN) {
487                         /* TUN device */
488                         flags |= TUN_TUN_DEV;
489                         name = "tun%d";
490                 } else if (ifr->ifr_flags & IFF_TAP) {
491                         /* TAP device */
492                         flags |= TUN_TAP_DEV;
493                         name = "tap%d";
494                 } else
495                         goto failed;
496
497                 if (*ifr->ifr_name)
498                         name = ifr->ifr_name;
499
500                 dev = alloc_netdev(sizeof(struct tun_struct), name,
501                                    tun_setup);
502                 if (!dev)
503                         return -ENOMEM;
504
505                 tun = netdev_priv(dev);
506                 tun->dev = dev;
507                 tun->flags = flags;
508                 /* Be promiscuous by default to maintain previous behaviour. */
509                 tun->if_flags = IFF_PROMISC;
510                 /* Generate random Ethernet address. */
511                 *(u16 *)tun->dev_addr = htons(0x00FF);
512                 get_random_bytes(tun->dev_addr + sizeof(u16), 4);
513                 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
514
515                 tun_net_init(dev);
516
517                 if (strchr(dev->name, '%')) {
518                         err = dev_alloc_name(dev, dev->name);
519                         if (err < 0)
520                                 goto err_free_dev;
521                 }
522
523                 err = register_netdevice(tun->dev);
524                 if (err < 0)
525                         goto err_free_dev;
526
527                 list_add(&tun->list, &tun_dev_list);
528         }
529
530         DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
531
532         if (ifr->ifr_flags & IFF_NO_PI)
533                 tun->flags |= TUN_NO_PI;
534
535         if (ifr->ifr_flags & IFF_ONE_QUEUE)
536                 tun->flags |= TUN_ONE_QUEUE;
537
538         file->private_data = tun;
539         tun->attached = 1;
540
541         strcpy(ifr->ifr_name, tun->dev->name);
542         return 0;
543
544  err_free_dev:
545         free_netdev(dev);
546  failed:
547         return err;
548 }
549
550 static int tun_chr_ioctl(struct inode *inode, struct file *file,
551                          unsigned int cmd, unsigned long arg)
552 {
553         struct tun_struct *tun = file->private_data;
554         void __user* argp = (void __user*)arg;
555         struct ifreq ifr;
556
557         if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
558                 if (copy_from_user(&ifr, argp, sizeof ifr))
559                         return -EFAULT;
560
561         if (cmd == TUNSETIFF && !tun) {
562                 int err;
563
564                 ifr.ifr_name[IFNAMSIZ-1] = '\0';
565
566                 rtnl_lock();
567                 err = tun_set_iff(file, &ifr);
568                 rtnl_unlock();
569
570                 if (err)
571                         return err;
572
573                 if (copy_to_user(argp, &ifr, sizeof(ifr)))
574                         return -EFAULT;
575                 return 0;
576         }
577
578         if (!tun)
579                 return -EBADFD;
580
581         DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
582
583         switch (cmd) {
584         case TUNSETNOCSUM:
585                 /* Disable/Enable checksum */
586                 if (arg)
587                         tun->flags |= TUN_NOCHECKSUM;
588                 else
589                         tun->flags &= ~TUN_NOCHECKSUM;
590
591                 DBG(KERN_INFO "%s: checksum %s\n",
592                     tun->dev->name, arg ? "disabled" : "enabled");
593                 break;
594
595         case TUNSETPERSIST:
596                 /* Disable/Enable persist mode */
597                 if (arg)
598                         tun->flags |= TUN_PERSIST;
599                 else
600                         tun->flags &= ~TUN_PERSIST;
601
602                 DBG(KERN_INFO "%s: persist %s\n",
603                     tun->dev->name, arg ? "disabled" : "enabled");
604                 break;
605
606         case TUNSETOWNER:
607                 /* Set owner of the device */
608                 tun->owner = (uid_t) arg;
609
610                 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
611                 break;
612
613         case TUNSETLINK:
614                 /* Only allow setting the type when the interface is down */
615                 if (tun->dev->flags & IFF_UP) {
616                         DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
617                                 tun->dev->name);
618                         return -EBUSY;
619                 } else {
620                         tun->dev->type = (int) arg;
621                         DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
622                 }
623                 break;
624
625 #ifdef TUN_DEBUG
626         case TUNSETDEBUG:
627                 tun->debug = arg;
628                 break;
629 #endif
630
631         case SIOCGIFFLAGS:
632                 ifr.ifr_flags = tun->if_flags;
633                 if (copy_to_user( argp, &ifr, sizeof ifr))
634                         return -EFAULT;
635                 return 0;
636
637         case SIOCSIFFLAGS:
638                 /** Set the character device's interface flags. Currently only
639                  * IFF_PROMISC and IFF_ALLMULTI are used. */
640                 tun->if_flags = ifr.ifr_flags;
641                 DBG(KERN_INFO "%s: interface flags 0x%lx\n",
642                                 tun->dev->name, tun->if_flags);
643                 return 0;
644
645         case SIOCGIFHWADDR:
646                 /* Note: the actual net device's address may be different */
647                 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
648                                 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
649                 if (copy_to_user( argp, &ifr, sizeof ifr))
650                         return -EFAULT;
651                 return 0;
652
653         case SIOCSIFHWADDR:
654         {
655                 /* try to set the actual net device's hw address */
656                 int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
657
658                 if (ret == 0) {
659                         /** Set the character device's hardware address. This is used when
660                          * filtering packets being sent from the network device to the character
661                          * device. */
662                         memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
663                                         min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
664                         DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
665                                         tun->dev->name,
666                                         tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
667                                         tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
668                 }
669
670                 return  ret;
671         }
672
673         case SIOCADDMULTI:
674                 /** Add the specified group to the character device's multicast filter
675                  * list. */
676                 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
677                 DBG(KERN_DEBUG "%s: add multi: %x:%x:%x:%x:%x:%x\n",
678                                 tun->dev->name,
679                                 (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1],
680                                 (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3],
681                                 (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]);
682                 return 0;
683
684         case SIOCDELMULTI:
685                 /** Remove the specified group from the character device's multicast
686                  * filter list. */
687                 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
688                 DBG(KERN_DEBUG "%s: del 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         default:
696                 return -EINVAL;
697         };
698
699         return 0;
700 }
701
702 static int tun_chr_fasync(int fd, struct file *file, int on)
703 {
704         struct tun_struct *tun = file->private_data;
705         int ret;
706
707         if (!tun)
708                 return -EBADFD;
709
710         DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
711
712         if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
713                 return ret;
714
715         if (on) {
716                 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
717                 if (ret)
718                         return ret;
719                 tun->flags |= TUN_FASYNC;
720         } else
721                 tun->flags &= ~TUN_FASYNC;
722
723         return 0;
724 }
725
726 static int tun_chr_open(struct inode *inode, struct file * file)
727 {
728         DBG1(KERN_INFO "tunX: tun_chr_open\n");
729         file->private_data = NULL;
730         return 0;
731 }
732
733 static int tun_chr_close(struct inode *inode, struct file *file)
734 {
735         struct tun_struct *tun = file->private_data;
736
737         if (!tun)
738                 return 0;
739
740         DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
741
742         tun_chr_fasync(-1, file, 0);
743
744         rtnl_lock();
745
746         /* Detach from net device */
747         file->private_data = NULL;
748         tun->attached = 0;
749
750         /* Drop read queue */
751         skb_queue_purge(&tun->readq);
752
753         if (!(tun->flags & TUN_PERSIST)) {
754                 list_del(&tun->list);
755                 unregister_netdevice(tun->dev);
756         }
757
758         rtnl_unlock();
759
760         return 0;
761 }
762
763 static const struct file_operations tun_fops = {
764         .owner  = THIS_MODULE,
765         .llseek = no_llseek,
766         .read  = do_sync_read,
767         .aio_read  = tun_chr_aio_read,
768         .write = do_sync_write,
769         .aio_write = tun_chr_aio_write,
770         .poll   = tun_chr_poll,
771         .ioctl  = tun_chr_ioctl,
772         .open   = tun_chr_open,
773         .release = tun_chr_close,
774         .fasync = tun_chr_fasync
775 };
776
777 static struct miscdevice tun_miscdev = {
778         .minor = TUN_MINOR,
779         .name = "tun",
780         .fops = &tun_fops,
781 };
782
783 /* ethtool interface */
784
785 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
786 {
787         cmd->supported          = 0;
788         cmd->advertising        = 0;
789         cmd->speed              = SPEED_10;
790         cmd->duplex             = DUPLEX_FULL;
791         cmd->port               = PORT_TP;
792         cmd->phy_address        = 0;
793         cmd->transceiver        = XCVR_INTERNAL;
794         cmd->autoneg            = AUTONEG_DISABLE;
795         cmd->maxtxpkt           = 0;
796         cmd->maxrxpkt           = 0;
797         return 0;
798 }
799
800 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
801 {
802         struct tun_struct *tun = netdev_priv(dev);
803
804         strcpy(info->driver, DRV_NAME);
805         strcpy(info->version, DRV_VERSION);
806         strcpy(info->fw_version, "N/A");
807
808         switch (tun->flags & TUN_TYPE_MASK) {
809         case TUN_TUN_DEV:
810                 strcpy(info->bus_info, "tun");
811                 break;
812         case TUN_TAP_DEV:
813                 strcpy(info->bus_info, "tap");
814                 break;
815         }
816 }
817
818 static u32 tun_get_msglevel(struct net_device *dev)
819 {
820 #ifdef TUN_DEBUG
821         struct tun_struct *tun = netdev_priv(dev);
822         return tun->debug;
823 #else
824         return -EOPNOTSUPP;
825 #endif
826 }
827
828 static void tun_set_msglevel(struct net_device *dev, u32 value)
829 {
830 #ifdef TUN_DEBUG
831         struct tun_struct *tun = netdev_priv(dev);
832         tun->debug = value;
833 #endif
834 }
835
836 static u32 tun_get_link(struct net_device *dev)
837 {
838         struct tun_struct *tun = netdev_priv(dev);
839         return tun->attached;
840 }
841
842 static u32 tun_get_rx_csum(struct net_device *dev)
843 {
844         struct tun_struct *tun = netdev_priv(dev);
845         return (tun->flags & TUN_NOCHECKSUM) == 0;
846 }
847
848 static int tun_set_rx_csum(struct net_device *dev, u32 data)
849 {
850         struct tun_struct *tun = netdev_priv(dev);
851         if (data)
852                 tun->flags &= ~TUN_NOCHECKSUM;
853         else
854                 tun->flags |= TUN_NOCHECKSUM;
855         return 0;
856 }
857
858 static const struct ethtool_ops tun_ethtool_ops = {
859         .get_settings   = tun_get_settings,
860         .get_drvinfo    = tun_get_drvinfo,
861         .get_msglevel   = tun_get_msglevel,
862         .set_msglevel   = tun_set_msglevel,
863         .get_link       = tun_get_link,
864         .get_rx_csum    = tun_get_rx_csum,
865         .set_rx_csum    = tun_set_rx_csum
866 };
867
868 static int __init tun_init(void)
869 {
870         int ret = 0;
871
872         printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
873         printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
874
875         ret = misc_register(&tun_miscdev);
876         if (ret)
877                 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
878         return ret;
879 }
880
881 static void tun_cleanup(void)
882 {
883         struct tun_struct *tun, *nxt;
884
885         misc_deregister(&tun_miscdev);
886
887         rtnl_lock();
888         list_for_each_entry_safe(tun, nxt, &tun_dev_list, list) {
889                 DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
890                 unregister_netdevice(tun->dev);
891         }
892         rtnl_unlock();
893
894 }
895
896 module_init(tun_init);
897 module_exit(tun_cleanup);
898 MODULE_DESCRIPTION(DRV_DESCRIPTION);
899 MODULE_AUTHOR(DRV_COPYRIGHT);
900 MODULE_LICENSE("GPL");
901 MODULE_ALIAS_MISCDEV(TUN_MINOR);