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kbuild: Fix instrumentation removal breakage on avr32
[wrt350n-kernel.git] / drivers / net / tun.c
blob46339f6bcd004b9ca6b443cad05df2c82742cf32
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 #include <net/net_namespace.h>
66
67 #include <asm/system.h>
68 #include <asm/uaccess.h>
69
70 #ifdef TUN_DEBUG
71 static int debug;
72 #endif
73
74 /* Network device part of the driver */
75
76 static LIST_HEAD(tun_dev_list);
77 static const struct ethtool_ops tun_ethtool_ops;
78
79 /* Net device open. */
80 static int tun_net_open(struct net_device *dev)
81 {
82 netif_start_queue(dev);
83 return 0;
84 }
85
86 /* Net device close. */
87 static int tun_net_close(struct net_device *dev)
88 {
89 netif_stop_queue(dev);
90 return 0;
91 }
92
93 /* Net device start xmit */
94 static 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. */
113 dev->stats.tx_fifo_errors++;
114 } 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
131 drop:
132 dev->stats.tx_dropped++;
133 kfree_skb(skb);
134 return 0;
135 }
136
137 /** Add the specified Ethernet address to this multicast filter. */
138 static void
139 add_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. */
146 static void
147 del_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. */
156 static void
157 tun_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;
162 DECLARE_MAC_BUF(mac);
163 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);
169 DBG(KERN_DEBUG "%s: tun_net_mclist: %s\n",
170 dev->name, print_mac(mac, mclist->dmi_addr));
171 }
172 }
173
174 #define MIN_MTU 68
175 #define MAX_MTU 65535
176
177 static int
178 tun_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
186 /* Initialize net device. */
187 static void tun_net_init(struct net_device *dev)
188 {
189 struct tun_struct *tun = netdev_priv(dev);
190
191 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;
197 dev->change_mtu = tun_net_change_mtu;
198
199 /* Zero header length */
200 dev->type = ARPHRD_NONE;
201 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);
210 dev->change_mtu = tun_net_change_mtu;
211
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
215 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 */
223 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
224 {
225 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);
234
235 if (!skb_queue_empty(&tun->readq))
236 mask |= POLLIN | POLLRDNORM;
237
238 return mask;
239 }
240
241 /* Get packet from user space buffer */
242 static __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;
258
259 if (!(skb = alloc_skb(len + align, GFP_KERNEL))) {
260 tun->dev->stats.rx_dropped++;
261 return -ENOMEM;
262 }
263
264 if (align)
265 skb_reserve(skb, align);
266 if (memcpy_fromiovec(skb_put(skb, len), iv, len)) {
267 tun->dev->stats.rx_dropped++;
268 kfree_skb(skb);
269 return -EFAULT;
270 }
271
272 switch (tun->flags & TUN_TYPE_MASK) {
273 case TUN_TUN_DEV:
274 skb_reset_mac_header(skb);
275 skb->protocol = pi.proto;
276 skb->dev = tun->dev;
277 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;
285
286 netif_rx_ni(skb);
287 tun->dev->last_rx = jiffies;
288
289 tun->dev->stats.rx_packets++;
290 tun->dev->stats.rx_bytes += len;
291
292 return count;
293 }
294
295 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
296 unsigned long count, loff_t pos)
297 {
298 struct tun_struct *tun = iocb->ki_filp->private_data;
299
300 if (!tun)
301 return -EBADFD;
302
303 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
304
305 return tun_get_user(tun, (struct iovec *) iv, iov_length(iv, count));
306 }
307
308 /* Put packet to the user space buffer */
309 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
310 struct sk_buff *skb,
311 struct iovec *iv, int len)
312 {
313 struct tun_pi pi = { 0, skb->protocol };
314 ssize_t total = 0;
315
316 if (!(tun->flags & TUN_NO_PI)) {
317 if ((len -= sizeof(pi)) < 0)
318 return -EINVAL;
319
320 if (len < skb->len) {
321 /* Packet will be striped */
322 pi.flags |= TUN_PKT_STRIP;
323 }
324
325 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
326 return -EFAULT;
327 total += sizeof(pi);
328 }
329
330 len = min_t(int, skb->len, len);
331
332 skb_copy_datagram_iovec(skb, 0, iv, len);
333 total += len;
334
335 tun->dev->stats.tx_packets++;
336 tun->dev->stats.tx_bytes += len;
337
338 return total;
339 }
340
341 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
342 unsigned long count, loff_t pos)
343 {
344 struct file *file = iocb->ki_filp;
345 struct tun_struct *tun = file->private_data;
346 DECLARE_WAITQUEUE(wait, current);
347 struct sk_buff *skb;
348 ssize_t len, ret = 0;
349 DECLARE_MAC_BUF(mac);
350
351 if (!tun)
352 return -EBADFD;
353
354 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
355
356 len = iov_length(iv, count);
357 if (len < 0)
358 return -EINVAL;
359
360 add_wait_queue(&tun->read_wait, &wait);
361 while (len) {
362 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
363 u8 addr[ ETH_ALEN];
364 int bit_nr;
365
366 current->state = TASK_INTERRUPTIBLE;
367
368 /* Read frames from the queue */
369 if (!(skb=skb_dequeue(&tun->readq))) {
370 if (file->f_flags & O_NONBLOCK) {
371 ret = -EAGAIN;
372 break;
373 }
374 if (signal_pending(current)) {
375 ret = -ERESTARTSYS;
376 break;
377 }
378
379 /* Nothing to read, let's sleep */
380 schedule();
381 continue;
382 }
383 netif_wake_queue(tun->dev);
384
385 /** Decide whether to accept this packet. This code is designed to
386 * behave identically to an Ethernet interface. Accept the packet if
387 * - we are promiscuous.
388 * - the packet is addressed to us.
389 * - the packet is broadcast.
390 * - the packet is multicast and
391 * - we are multicast promiscous.
392 * - we belong to the multicast group.
393 */
394 skb_copy_from_linear_data(skb, addr, min_t(size_t, sizeof addr,
395 skb->len));
396 bit_nr = ether_crc(sizeof addr, addr) >> 26;
397 if ((tun->if_flags & IFF_PROMISC) ||
398 memcmp(addr, tun->dev_addr, sizeof addr) == 0 ||
399 memcmp(addr, ones, sizeof addr) == 0 ||
400 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) ||
401 (addr[0] == 0x33 && addr[1] == 0x33)) &&
402 ((tun->if_flags & IFF_ALLMULTI) ||
403 (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) {
404 DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %s\n",
405 tun->dev->name, print_mac(mac, addr));
406 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
407 kfree_skb(skb);
408 break;
409 } else {
410 DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %s\n",
411 tun->dev->name, print_mac(mac, addr));
412 kfree_skb(skb);
413 continue;
414 }
415 }
416
417 current->state = TASK_RUNNING;
418 remove_wait_queue(&tun->read_wait, &wait);
419
420 return ret;
421 }
422
423 static void tun_setup(struct net_device *dev)
424 {
425 struct tun_struct *tun = netdev_priv(dev);
426
427 skb_queue_head_init(&tun->readq);
428 init_waitqueue_head(&tun->read_wait);
429
430 tun->owner = -1;
431 tun->group = -1;
432
433 dev->open = tun_net_open;
434 dev->hard_start_xmit = tun_net_xmit;
435 dev->stop = tun_net_close;
436 dev->ethtool_ops = &tun_ethtool_ops;
437 dev->destructor = free_netdev;
438 }
439
440 static struct tun_struct *tun_get_by_name(const char *name)
441 {
442 struct tun_struct *tun;
443
444 ASSERT_RTNL();
445 list_for_each_entry(tun, &tun_dev_list, list) {
446 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
447 return tun;
448 }
449
450 return NULL;
451 }
452
453 static int tun_set_iff(struct file *file, struct ifreq *ifr)
454 {
455 struct tun_struct *tun;
456 struct net_device *dev;
457 int err;
458
459 tun = tun_get_by_name(ifr->ifr_name);
460 if (tun) {
461 if (tun->attached)
462 return -EBUSY;
463
464 /* Check permissions */
465 if (((tun->owner != -1 &&
466 current->euid != tun->owner) ||
467 (tun->group != -1 &&
468 current->egid != tun->group)) &&
469 !capable(CAP_NET_ADMIN))
470 return -EPERM;
471 }
472 else if (__dev_get_by_name(&init_net, ifr->ifr_name))
473 return -EINVAL;
474 else {
475 char *name;
476 unsigned long flags = 0;
477
478 err = -EINVAL;
479
480 if (!capable(CAP_NET_ADMIN))
481 return -EPERM;
482
483 /* Set dev type */
484 if (ifr->ifr_flags & IFF_TUN) {
485 /* TUN device */
486 flags |= TUN_TUN_DEV;
487 name = "tun%d";
488 } else if (ifr->ifr_flags & IFF_TAP) {
489 /* TAP device */
490 flags |= TUN_TAP_DEV;
491 name = "tap%d";
492 } else
493 goto failed;
494
495 if (*ifr->ifr_name)
496 name = ifr->ifr_name;
497
498 dev = alloc_netdev(sizeof(struct tun_struct), name,
499 tun_setup);
500 if (!dev)
501 return -ENOMEM;
502
503 tun = netdev_priv(dev);
504 tun->dev = dev;
505 tun->flags = flags;
506 /* Be promiscuous by default to maintain previous behaviour. */
507 tun->if_flags = IFF_PROMISC;
508 /* Generate random Ethernet address. */
509 *(__be16 *)tun->dev_addr = htons(0x00FF);
510 get_random_bytes(tun->dev_addr + sizeof(u16), 4);
511 memset(tun->chr_filter, 0, sizeof tun->chr_filter);
512
513 tun_net_init(dev);
514
515 if (strchr(dev->name, '%')) {
516 err = dev_alloc_name(dev, dev->name);
517 if (err < 0)
518 goto err_free_dev;
519 }
520
521 err = register_netdevice(tun->dev);
522 if (err < 0)
523 goto err_free_dev;
524
525 list_add(&tun->list, &tun_dev_list);
526 }
527
528 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
529
530 if (ifr->ifr_flags & IFF_NO_PI)
531 tun->flags |= TUN_NO_PI;
532
533 if (ifr->ifr_flags & IFF_ONE_QUEUE)
534 tun->flags |= TUN_ONE_QUEUE;
535
536 file->private_data = tun;
537 tun->attached = 1;
538
539 strcpy(ifr->ifr_name, tun->dev->name);
540 return 0;
541
542 err_free_dev:
543 free_netdev(dev);
544 failed:
545 return err;
546 }
547
548 static int tun_chr_ioctl(struct inode *inode, struct file *file,
549 unsigned int cmd, unsigned long arg)
550 {
551 struct tun_struct *tun = file->private_data;
552 void __user* argp = (void __user*)arg;
553 struct ifreq ifr;
554 DECLARE_MAC_BUF(mac);
555
556 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
557 if (copy_from_user(&ifr, argp, sizeof ifr))
558 return -EFAULT;
559
560 if (cmd == TUNSETIFF && !tun) {
561 int err;
562
563 ifr.ifr_name[IFNAMSIZ-1] = '\0';
564
565 rtnl_lock();
566 err = tun_set_iff(file, &ifr);
567 rtnl_unlock();
568
569 if (err)
570 return err;
571
572 if (copy_to_user(argp, &ifr, sizeof(ifr)))
573 return -EFAULT;
574 return 0;
575 }
576
577 if (!tun)
578 return -EBADFD;
579
580 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
581
582 switch (cmd) {
583 case TUNSETNOCSUM:
584 /* Disable/Enable checksum */
585 if (arg)
586 tun->flags |= TUN_NOCHECKSUM;
587 else
588 tun->flags &= ~TUN_NOCHECKSUM;
589
590 DBG(KERN_INFO "%s: checksum %s\n",
591 tun->dev->name, arg ? "disabled" : "enabled");
592 break;
593
594 case TUNSETPERSIST:
595 /* Disable/Enable persist mode */
596 if (arg)
597 tun->flags |= TUN_PERSIST;
598 else
599 tun->flags &= ~TUN_PERSIST;
600
601 DBG(KERN_INFO "%s: persist %s\n",
602 tun->dev->name, arg ? "enabled" : "disabled");
603 break;
604
605 case TUNSETOWNER:
606 /* Set owner of the device */
607 tun->owner = (uid_t) arg;
608
609 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
610 break;
611
612 case TUNSETGROUP:
613 /* Set group of the device */
614 tun->group= (gid_t) arg;
615
616 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
617 break;
618
619 case TUNSETLINK:
620 /* Only allow setting the type when the interface is down */
621 if (tun->dev->flags & IFF_UP) {
622 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
623 tun->dev->name);
624 return -EBUSY;
625 } else {
626 tun->dev->type = (int) arg;
627 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
628 }
629 break;
630
631 #ifdef TUN_DEBUG
632 case TUNSETDEBUG:
633 tun->debug = arg;
634 break;
635 #endif
636
637 case SIOCGIFFLAGS:
638 ifr.ifr_flags = tun->if_flags;
639 if (copy_to_user( argp, &ifr, sizeof ifr))
640 return -EFAULT;
641 return 0;
642
643 case SIOCSIFFLAGS:
644 /** Set the character device's interface flags. Currently only
645 * IFF_PROMISC and IFF_ALLMULTI are used. */
646 tun->if_flags = ifr.ifr_flags;
647 DBG(KERN_INFO "%s: interface flags 0x%lx\n",
648 tun->dev->name, tun->if_flags);
649 return 0;
650
651 case SIOCGIFHWADDR:
652 /* Note: the actual net device's address may be different */
653 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr,
654 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
655 if (copy_to_user( argp, &ifr, sizeof ifr))
656 return -EFAULT;
657 return 0;
658
659 case SIOCSIFHWADDR:
660 {
661 /* try to set the actual net device's hw address */
662 int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
663
664 if (ret == 0) {
665 /** Set the character device's hardware address. This is used when
666 * filtering packets being sent from the network device to the character
667 * device. */
668 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data,
669 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr));
670 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n",
671 tun->dev->name,
672 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2],
673 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]);
674 }
675
676 return ret;
677 }
678
679 case SIOCADDMULTI:
680 /** Add the specified group to the character device's multicast filter
681 * list. */
682 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
683 DBG(KERN_DEBUG "%s: add multi: %s\n",
684 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
685 return 0;
686
687 case SIOCDELMULTI:
688 /** Remove the specified group from the character device's multicast
689 * filter list. */
690 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data);
691 DBG(KERN_DEBUG "%s: del multi: %s\n",
692 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data));
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);
WRT350N Kernel Patches