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Staging: strip: delete the driver
[linux/fpc-iii.git] / drivers / net / tun.c
blob43265207d46370c97789a4ac264acc2d4238dbad
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/compat.h>
57 #include <linux/if.h>
58 #include <linux/if_arp.h>
59 #include <linux/if_ether.h>
60 #include <linux/if_tun.h>
61 #include <linux/crc32.h>
62 #include <linux/nsproxy.h>
63 #include <linux/virtio_net.h>
64 #include <linux/rcupdate.h>
65 #include <net/net_namespace.h>
66 #include <net/netns/generic.h>
67 #include <net/rtnetlink.h>
68 #include <net/sock.h>
69
70 #include <asm/system.h>
71 #include <asm/uaccess.h>
72
73 /* Uncomment to enable debugging */
74 /* #define TUN_DEBUG 1 */
75
76 #ifdef TUN_DEBUG
77 static int debug;
78
79 #define DBG if(tun->debug)printk
80 #define DBG1 if(debug==2)printk
81 #else
82 #define DBG( a... )
83 #define DBG1( a... )
84 #endif
85
86 #define FLT_EXACT_COUNT 8
87 struct tap_filter {
88 unsigned int count; /* Number of addrs. Zero means disabled */
89 u32 mask[2]; /* Mask of the hashed addrs */
90 unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
91 };
92
93 struct tun_file {
94 atomic_t count;
95 struct tun_struct *tun;
96 struct net *net;
97 };
98
99 struct tun_sock;
100
101 struct tun_struct {
102 struct tun_file *tfile;
103 unsigned int flags;
104 uid_t owner;
105 gid_t group;
106
107 struct net_device *dev;
108 struct fasync_struct *fasync;
109
110 struct tap_filter txflt;
111 struct socket socket;
112
113 #ifdef TUN_DEBUG
114 int debug;
115 #endif
116 };
117
118 struct tun_sock {
119 struct sock sk;
120 struct tun_struct *tun;
121 };
122
123 static inline struct tun_sock *tun_sk(struct sock *sk)
124 {
125 return container_of(sk, struct tun_sock, sk);
126 }
127
128 static int tun_attach(struct tun_struct *tun, struct file *file)
129 {
130 struct tun_file *tfile = file->private_data;
131 int err;
132
133 ASSERT_RTNL();
134
135 netif_tx_lock_bh(tun->dev);
136
137 err = -EINVAL;
138 if (tfile->tun)
139 goto out;
140
141 err = -EBUSY;
142 if (tun->tfile)
143 goto out;
144
145 err = 0;
146 tfile->tun = tun;
147 tun->tfile = tfile;
148 tun->socket.file = file;
149 dev_hold(tun->dev);
150 sock_hold(tun->socket.sk);
151 atomic_inc(&tfile->count);
152
153 out:
154 netif_tx_unlock_bh(tun->dev);
155 return err;
156 }
157
158 static void __tun_detach(struct tun_struct *tun)
159 {
160 /* Detach from net device */
161 netif_tx_lock_bh(tun->dev);
162 tun->tfile = NULL;
163 tun->socket.file = NULL;
164 netif_tx_unlock_bh(tun->dev);
165
166 /* Drop read queue */
167 skb_queue_purge(&tun->socket.sk->sk_receive_queue);
168
169 /* Drop the extra count on the net device */
170 dev_put(tun->dev);
171 }
172
173 static void tun_detach(struct tun_struct *tun)
174 {
175 rtnl_lock();
176 __tun_detach(tun);
177 rtnl_unlock();
178 }
179
180 static struct tun_struct *__tun_get(struct tun_file *tfile)
181 {
182 struct tun_struct *tun = NULL;
183
184 if (atomic_inc_not_zero(&tfile->count))
185 tun = tfile->tun;
186
187 return tun;
188 }
189
190 static struct tun_struct *tun_get(struct file *file)
191 {
192 return __tun_get(file->private_data);
193 }
194
195 static void tun_put(struct tun_struct *tun)
196 {
197 struct tun_file *tfile = tun->tfile;
198
199 if (atomic_dec_and_test(&tfile->count))
200 tun_detach(tfile->tun);
201 }
202
203 /* TAP filterting */
204 static void addr_hash_set(u32 *mask, const u8 *addr)
205 {
206 int n = ether_crc(ETH_ALEN, addr) >> 26;
207 mask[n >> 5] |= (1 << (n & 31));
208 }
209
210 static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
211 {
212 int n = ether_crc(ETH_ALEN, addr) >> 26;
213 return mask[n >> 5] & (1 << (n & 31));
214 }
215
216 static int update_filter(struct tap_filter *filter, void __user *arg)
217 {
218 struct { u8 u[ETH_ALEN]; } *addr;
219 struct tun_filter uf;
220 int err, alen, n, nexact;
221
222 if (copy_from_user(&uf, arg, sizeof(uf)))
223 return -EFAULT;
224
225 if (!uf.count) {
226 /* Disabled */
227 filter->count = 0;
228 return 0;
229 }
230
231 alen = ETH_ALEN * uf.count;
232 addr = kmalloc(alen, GFP_KERNEL);
233 if (!addr)
234 return -ENOMEM;
235
236 if (copy_from_user(addr, arg + sizeof(uf), alen)) {
237 err = -EFAULT;
238 goto done;
239 }
240
241 /* The filter is updated without holding any locks. Which is
242 * perfectly safe. We disable it first and in the worst
243 * case we'll accept a few undesired packets. */
244 filter->count = 0;
245 wmb();
246
247 /* Use first set of addresses as an exact filter */
248 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
249 memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
250
251 nexact = n;
252
253 /* Remaining multicast addresses are hashed,
254 * unicast will leave the filter disabled. */
255 memset(filter->mask, 0, sizeof(filter->mask));
256 for (; n < uf.count; n++) {
257 if (!is_multicast_ether_addr(addr[n].u)) {
258 err = 0; /* no filter */
259 goto done;
260 }
261 addr_hash_set(filter->mask, addr[n].u);
262 }
263
264 /* For ALLMULTI just set the mask to all ones.
265 * This overrides the mask populated above. */
266 if ((uf.flags & TUN_FLT_ALLMULTI))
267 memset(filter->mask, ~0, sizeof(filter->mask));
268
269 /* Now enable the filter */
270 wmb();
271 filter->count = nexact;
272
273 /* Return the number of exact filters */
274 err = nexact;
275
276 done:
277 kfree(addr);
278 return err;
279 }
280
281 /* Returns: 0 - drop, !=0 - accept */
282 static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
283 {
284 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
285 * at this point. */
286 struct ethhdr *eh = (struct ethhdr *) skb->data;
287 int i;
288
289 /* Exact match */
290 for (i = 0; i < filter->count; i++)
291 if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
292 return 1;
293
294 /* Inexact match (multicast only) */
295 if (is_multicast_ether_addr(eh->h_dest))
296 return addr_hash_test(filter->mask, eh->h_dest);
297
298 return 0;
299 }
300
301 /*
302 * Checks whether the packet is accepted or not.
303 * Returns: 0 - drop, !=0 - accept
304 */
305 static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
306 {
307 if (!filter->count)
308 return 1;
309
310 return run_filter(filter, skb);
311 }
312
313 /* Network device part of the driver */
314
315 static const struct ethtool_ops tun_ethtool_ops;
316
317 /* Net device detach from fd. */
318 static void tun_net_uninit(struct net_device *dev)
319 {
320 struct tun_struct *tun = netdev_priv(dev);
321 struct tun_file *tfile = tun->tfile;
322
323 /* Inform the methods they need to stop using the dev.
324 */
325 if (tfile) {
326 wake_up_all(&tun->socket.wait);
327 if (atomic_dec_and_test(&tfile->count))
328 __tun_detach(tun);
329 }
330 }
331
332 static void tun_free_netdev(struct net_device *dev)
333 {
334 struct tun_struct *tun = netdev_priv(dev);
335
336 sock_put(tun->socket.sk);
337 }
338
339 /* Net device open. */
340 static int tun_net_open(struct net_device *dev)
341 {
342 netif_start_queue(dev);
343 return 0;
344 }
345
346 /* Net device close. */
347 static int tun_net_close(struct net_device *dev)
348 {
349 netif_stop_queue(dev);
350 return 0;
351 }
352
353 /* Net device start xmit */
354 static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
355 {
356 struct tun_struct *tun = netdev_priv(dev);
357
358 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
359
360 /* Drop packet if interface is not attached */
361 if (!tun->tfile)
362 goto drop;
363
364 /* Drop if the filter does not like it.
365 * This is a noop if the filter is disabled.
366 * Filter can be enabled only for the TAP devices. */
367 if (!check_filter(&tun->txflt, skb))
368 goto drop;
369
370 if (tun->socket.sk->sk_filter &&
371 sk_filter(tun->socket.sk, skb))
372 goto drop;
373
374 if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) {
375 if (!(tun->flags & TUN_ONE_QUEUE)) {
376 /* Normal queueing mode. */
377 /* Packet scheduler handles dropping of further packets. */
378 netif_stop_queue(dev);
379
380 /* We won't see all dropped packets individually, so overrun
381 * error is more appropriate. */
382 dev->stats.tx_fifo_errors++;
383 } else {
384 /* Single queue mode.
385 * Driver handles dropping of all packets itself. */
386 goto drop;
387 }
388 }
389
390 /* Orphan the skb - required as we might hang on to it
391 * for indefinite time. */
392 skb_orphan(skb);
393
394 /* Enqueue packet */
395 skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb);
396 dev->trans_start = jiffies;
397
398 /* Notify and wake up reader process */
399 if (tun->flags & TUN_FASYNC)
400 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
401 wake_up_interruptible_poll(&tun->socket.wait, POLLIN |
402 POLLRDNORM | POLLRDBAND);
403 return NETDEV_TX_OK;
404
405 drop:
406 dev->stats.tx_dropped++;
407 kfree_skb(skb);
408 return NETDEV_TX_OK;
409 }
410
411 static void tun_net_mclist(struct net_device *dev)
412 {
413 /*
414 * This callback is supposed to deal with mc filter in
415 * _rx_ path and has nothing to do with the _tx_ path.
416 * In rx path we always accept everything userspace gives us.
417 */
418 return;
419 }
420
421 #define MIN_MTU 68
422 #define MAX_MTU 65535
423
424 static int
425 tun_net_change_mtu(struct net_device *dev, int new_mtu)
426 {
427 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
428 return -EINVAL;
429 dev->mtu = new_mtu;
430 return 0;
431 }
432
433 static const struct net_device_ops tun_netdev_ops = {
434 .ndo_uninit = tun_net_uninit,
435 .ndo_open = tun_net_open,
436 .ndo_stop = tun_net_close,
437 .ndo_start_xmit = tun_net_xmit,
438 .ndo_change_mtu = tun_net_change_mtu,
439 };
440
441 static const struct net_device_ops tap_netdev_ops = {
442 .ndo_uninit = tun_net_uninit,
443 .ndo_open = tun_net_open,
444 .ndo_stop = tun_net_close,
445 .ndo_start_xmit = tun_net_xmit,
446 .ndo_change_mtu = tun_net_change_mtu,
447 .ndo_set_multicast_list = tun_net_mclist,
448 .ndo_set_mac_address = eth_mac_addr,
449 .ndo_validate_addr = eth_validate_addr,
450 };
451
452 /* Initialize net device. */
453 static void tun_net_init(struct net_device *dev)
454 {
455 struct tun_struct *tun = netdev_priv(dev);
456
457 switch (tun->flags & TUN_TYPE_MASK) {
458 case TUN_TUN_DEV:
459 dev->netdev_ops = &tun_netdev_ops;
460
461 /* Point-to-Point TUN Device */
462 dev->hard_header_len = 0;
463 dev->addr_len = 0;
464 dev->mtu = 1500;
465
466 /* Zero header length */
467 dev->type = ARPHRD_NONE;
468 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
469 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
470 break;
471
472 case TUN_TAP_DEV:
473 dev->netdev_ops = &tap_netdev_ops;
474 /* Ethernet TAP Device */
475 ether_setup(dev);
476
477 random_ether_addr(dev->dev_addr);
478
479 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
480 break;
481 }
482 }
483
484 /* Character device part */
485
486 /* Poll */
487 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
488 {
489 struct tun_file *tfile = file->private_data;
490 struct tun_struct *tun = __tun_get(tfile);
491 struct sock *sk;
492 unsigned int mask = 0;
493
494 if (!tun)
495 return POLLERR;
496
497 sk = tun->socket.sk;
498
499 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
500
501 poll_wait(file, &tun->socket.wait, wait);
502
503 if (!skb_queue_empty(&sk->sk_receive_queue))
504 mask |= POLLIN | POLLRDNORM;
505
506 if (sock_writeable(sk) ||
507 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
508 sock_writeable(sk)))
509 mask |= POLLOUT | POLLWRNORM;
510
511 if (tun->dev->reg_state != NETREG_REGISTERED)
512 mask = POLLERR;
513
514 tun_put(tun);
515 return mask;
516 }
517
518 /* prepad is the amount to reserve at front. len is length after that.
519 * linear is a hint as to how much to copy (usually headers). */
520 static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
521 size_t prepad, size_t len,
522 size_t linear, int noblock)
523 {
524 struct sock *sk = tun->socket.sk;
525 struct sk_buff *skb;
526 int err;
527
528 /* Under a page? Don't bother with paged skb. */
529 if (prepad + len < PAGE_SIZE || !linear)
530 linear = len;
531
532 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
533 &err);
534 if (!skb)
535 return ERR_PTR(err);
536
537 skb_reserve(skb, prepad);
538 skb_put(skb, linear);
539 skb->data_len = len - linear;
540 skb->len += len - linear;
541
542 return skb;
543 }
544
545 /* Get packet from user space buffer */
546 static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
547 const struct iovec *iv, size_t count,
548 int noblock)
549 {
550 struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
551 struct sk_buff *skb;
552 size_t len = count, align = 0;
553 struct virtio_net_hdr gso = { 0 };
554 int offset = 0;
555
556 if (!(tun->flags & TUN_NO_PI)) {
557 if ((len -= sizeof(pi)) > count)
558 return -EINVAL;
559
560 if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi)))
561 return -EFAULT;
562 offset += sizeof(pi);
563 }
564
565 if (tun->flags & TUN_VNET_HDR) {
566 if ((len -= sizeof(gso)) > count)
567 return -EINVAL;
568
569 if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso)))
570 return -EFAULT;
571
572 if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
573 gso.csum_start + gso.csum_offset + 2 > gso.hdr_len)
574 gso.hdr_len = gso.csum_start + gso.csum_offset + 2;
575
576 if (gso.hdr_len > len)
577 return -EINVAL;
578 offset += sizeof(gso);
579 }
580
581 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
582 align = NET_IP_ALIGN;
583 if (unlikely(len < ETH_HLEN ||
584 (gso.hdr_len && gso.hdr_len < ETH_HLEN)))
585 return -EINVAL;
586 }
587
588 skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock);
589 if (IS_ERR(skb)) {
590 if (PTR_ERR(skb) != -EAGAIN)
591 tun->dev->stats.rx_dropped++;
592 return PTR_ERR(skb);
593 }
594
595 if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) {
596 tun->dev->stats.rx_dropped++;
597 kfree_skb(skb);
598 return -EFAULT;
599 }
600
601 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
602 if (!skb_partial_csum_set(skb, gso.csum_start,
603 gso.csum_offset)) {
604 tun->dev->stats.rx_frame_errors++;
605 kfree_skb(skb);
606 return -EINVAL;
607 }
608 } else if (tun->flags & TUN_NOCHECKSUM)
609 skb->ip_summed = CHECKSUM_UNNECESSARY;
610
611 switch (tun->flags & TUN_TYPE_MASK) {
612 case TUN_TUN_DEV:
613 if (tun->flags & TUN_NO_PI) {
614 switch (skb->data[0] & 0xf0) {
615 case 0x40:
616 pi.proto = htons(ETH_P_IP);
617 break;
618 case 0x60:
619 pi.proto = htons(ETH_P_IPV6);
620 break;
621 default:
622 tun->dev->stats.rx_dropped++;
623 kfree_skb(skb);
624 return -EINVAL;
625 }
626 }
627
628 skb_reset_mac_header(skb);
629 skb->protocol = pi.proto;
630 skb->dev = tun->dev;
631 break;
632 case TUN_TAP_DEV:
633 skb->protocol = eth_type_trans(skb, tun->dev);
634 break;
635 };
636
637 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
638 pr_debug("GSO!\n");
639 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
640 case VIRTIO_NET_HDR_GSO_TCPV4:
641 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
642 break;
643 case VIRTIO_NET_HDR_GSO_TCPV6:
644 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
645 break;
646 case VIRTIO_NET_HDR_GSO_UDP:
647 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
648 break;
649 default:
650 tun->dev->stats.rx_frame_errors++;
651 kfree_skb(skb);
652 return -EINVAL;
653 }
654
655 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
656 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
657
658 skb_shinfo(skb)->gso_size = gso.gso_size;
659 if (skb_shinfo(skb)->gso_size == 0) {
660 tun->dev->stats.rx_frame_errors++;
661 kfree_skb(skb);
662 return -EINVAL;
663 }
664
665 /* Header must be checked, and gso_segs computed. */
666 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
667 skb_shinfo(skb)->gso_segs = 0;
668 }
669
670 netif_rx_ni(skb);
671
672 tun->dev->stats.rx_packets++;
673 tun->dev->stats.rx_bytes += len;
674
675 return count;
676 }
677
678 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
679 unsigned long count, loff_t pos)
680 {
681 struct file *file = iocb->ki_filp;
682 struct tun_struct *tun = tun_get(file);
683 ssize_t result;
684
685 if (!tun)
686 return -EBADFD;
687
688 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
689
690 result = tun_get_user(tun, iv, iov_length(iv, count),
691 file->f_flags & O_NONBLOCK);
692
693 tun_put(tun);
694 return result;
695 }
696
697 /* Put packet to the user space buffer */
698 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
699 struct sk_buff *skb,
700 const struct iovec *iv, int len)
701 {
702 struct tun_pi pi = { 0, skb->protocol };
703 ssize_t total = 0;
704
705 if (!(tun->flags & TUN_NO_PI)) {
706 if ((len -= sizeof(pi)) < 0)
707 return -EINVAL;
708
709 if (len < skb->len) {
710 /* Packet will be striped */
711 pi.flags |= TUN_PKT_STRIP;
712 }
713
714 if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi)))
715 return -EFAULT;
716 total += sizeof(pi);
717 }
718
719 if (tun->flags & TUN_VNET_HDR) {
720 struct virtio_net_hdr gso = { 0 }; /* no info leak */
721 if ((len -= sizeof(gso)) < 0)
722 return -EINVAL;
723
724 if (skb_is_gso(skb)) {
725 struct skb_shared_info *sinfo = skb_shinfo(skb);
726
727 /* This is a hint as to how much should be linear. */
728 gso.hdr_len = skb_headlen(skb);
729 gso.gso_size = sinfo->gso_size;
730 if (sinfo->gso_type & SKB_GSO_TCPV4)
731 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
732 else if (sinfo->gso_type & SKB_GSO_TCPV6)
733 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
734 else if (sinfo->gso_type & SKB_GSO_UDP)
735 gso.gso_type = VIRTIO_NET_HDR_GSO_UDP;
736 else
737 BUG();
738 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
739 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
740 } else
741 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
742
743 if (skb->ip_summed == CHECKSUM_PARTIAL) {
744 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
745 gso.csum_start = skb->csum_start - skb_headroom(skb);
746 gso.csum_offset = skb->csum_offset;
747 } /* else everything is zero */
748
749 if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
750 sizeof(gso))))
751 return -EFAULT;
752 total += sizeof(gso);
753 }
754
755 len = min_t(int, skb->len, len);
756
757 skb_copy_datagram_const_iovec(skb, 0, iv, total, len);
758 total += skb->len;
759
760 tun->dev->stats.tx_packets++;
761 tun->dev->stats.tx_bytes += len;
762
763 return total;
764 }
765
766 static ssize_t tun_do_read(struct tun_struct *tun,
767 struct kiocb *iocb, const struct iovec *iv,
768 ssize_t len, int noblock)
769 {
770 DECLARE_WAITQUEUE(wait, current);
771 struct sk_buff *skb;
772 ssize_t ret = 0;
773
774 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
775
776 add_wait_queue(&tun->socket.wait, &wait);
777 while (len) {
778 current->state = TASK_INTERRUPTIBLE;
779
780 /* Read frames from the queue */
781 if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) {
782 if (noblock) {
783 ret = -EAGAIN;
784 break;
785 }
786 if (signal_pending(current)) {
787 ret = -ERESTARTSYS;
788 break;
789 }
790 if (tun->dev->reg_state != NETREG_REGISTERED) {
791 ret = -EIO;
792 break;
793 }
794
795 /* Nothing to read, let's sleep */
796 schedule();
797 continue;
798 }
799 netif_wake_queue(tun->dev);
800
801 ret = tun_put_user(tun, skb, iv, len);
802 kfree_skb(skb);
803 break;
804 }
805
806 current->state = TASK_RUNNING;
807 remove_wait_queue(&tun->socket.wait, &wait);
808
809 return ret;
810 }
811
812 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
813 unsigned long count, loff_t pos)
814 {
815 struct file *file = iocb->ki_filp;
816 struct tun_file *tfile = file->private_data;
817 struct tun_struct *tun = __tun_get(tfile);
818 ssize_t len, ret;
819
820 if (!tun)
821 return -EBADFD;
822 len = iov_length(iv, count);
823 if (len < 0) {
824 ret = -EINVAL;
825 goto out;
826 }
827
828 ret = tun_do_read(tun, iocb, iv, len, file->f_flags & O_NONBLOCK);
829 ret = min_t(ssize_t, ret, len);
830 out:
831 tun_put(tun);
832 return ret;
833 }
834
835 static void tun_setup(struct net_device *dev)
836 {
837 struct tun_struct *tun = netdev_priv(dev);
838
839 tun->owner = -1;
840 tun->group = -1;
841
842 dev->ethtool_ops = &tun_ethtool_ops;
843 dev->destructor = tun_free_netdev;
844 }
845
846 /* Trivial set of netlink ops to allow deleting tun or tap
847 * device with netlink.
848 */
849 static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
850 {
851 return -EINVAL;
852 }
853
854 static struct rtnl_link_ops tun_link_ops __read_mostly = {
855 .kind = DRV_NAME,
856 .priv_size = sizeof(struct tun_struct),
857 .setup = tun_setup,
858 .validate = tun_validate,
859 };
860
861 static void tun_sock_write_space(struct sock *sk)
862 {
863 struct tun_struct *tun;
864
865 if (!sock_writeable(sk))
866 return;
867
868 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
869 return;
870
871 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
872 wake_up_interruptible_sync_poll(sk->sk_sleep, POLLOUT |
873 POLLWRNORM | POLLWRBAND);
874
875 tun = tun_sk(sk)->tun;
876 kill_fasync(&tun->fasync, SIGIO, POLL_OUT);
877 }
878
879 static void tun_sock_destruct(struct sock *sk)
880 {
881 free_netdev(tun_sk(sk)->tun->dev);
882 }
883
884 static int tun_sendmsg(struct kiocb *iocb, struct socket *sock,
885 struct msghdr *m, size_t total_len)
886 {
887 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
888 return tun_get_user(tun, m->msg_iov, total_len,
889 m->msg_flags & MSG_DONTWAIT);
890 }
891
892 static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
893 struct msghdr *m, size_t total_len,
894 int flags)
895 {
896 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
897 int ret;
898 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
899 return -EINVAL;
900 ret = tun_do_read(tun, iocb, m->msg_iov, total_len,
901 flags & MSG_DONTWAIT);
902 if (ret > total_len) {
903 m->msg_flags |= MSG_TRUNC;
904 ret = flags & MSG_TRUNC ? ret : total_len;
905 }
906 return ret;
907 }
908
909 /* Ops structure to mimic raw sockets with tun */
910 static const struct proto_ops tun_socket_ops = {
911 .sendmsg = tun_sendmsg,
912 .recvmsg = tun_recvmsg,
913 };
914
915 static struct proto tun_proto = {
916 .name = "tun",
917 .owner = THIS_MODULE,
918 .obj_size = sizeof(struct tun_sock),
919 };
920
921 static int tun_flags(struct tun_struct *tun)
922 {
923 int flags = 0;
924
925 if (tun->flags & TUN_TUN_DEV)
926 flags |= IFF_TUN;
927 else
928 flags |= IFF_TAP;
929
930 if (tun->flags & TUN_NO_PI)
931 flags |= IFF_NO_PI;
932
933 if (tun->flags & TUN_ONE_QUEUE)
934 flags |= IFF_ONE_QUEUE;
935
936 if (tun->flags & TUN_VNET_HDR)
937 flags |= IFF_VNET_HDR;
938
939 return flags;
940 }
941
942 static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr,
943 char *buf)
944 {
945 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
946 return sprintf(buf, "0x%x\n", tun_flags(tun));
947 }
948
949 static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr,
950 char *buf)
951 {
952 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
953 return sprintf(buf, "%d\n", tun->owner);
954 }
955
956 static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
957 char *buf)
958 {
959 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
960 return sprintf(buf, "%d\n", tun->group);
961 }
962
963 static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
964 static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL);
965 static DEVICE_ATTR(group, 0444, tun_show_group, NULL);
966
967 static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
968 {
969 struct sock *sk;
970 struct tun_struct *tun;
971 struct net_device *dev;
972 int err;
973
974 dev = __dev_get_by_name(net, ifr->ifr_name);
975 if (dev) {
976 const struct cred *cred = current_cred();
977
978 if (ifr->ifr_flags & IFF_TUN_EXCL)
979 return -EBUSY;
980 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
981 tun = netdev_priv(dev);
982 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
983 tun = netdev_priv(dev);
984 else
985 return -EINVAL;
986
987 if (((tun->owner != -1 && cred->euid != tun->owner) ||
988 (tun->group != -1 && !in_egroup_p(tun->group))) &&
989 !capable(CAP_NET_ADMIN))
990 return -EPERM;
991 err = security_tun_dev_attach(tun->socket.sk);
992 if (err < 0)
993 return err;
994
995 err = tun_attach(tun, file);
996 if (err < 0)
997 return err;
998 }
999 else {
1000 char *name;
1001 unsigned long flags = 0;
1002
1003 if (!capable(CAP_NET_ADMIN))
1004 return -EPERM;
1005 err = security_tun_dev_create();
1006 if (err < 0)
1007 return err;
1008
1009 /* Set dev type */
1010 if (ifr->ifr_flags & IFF_TUN) {
1011 /* TUN device */
1012 flags |= TUN_TUN_DEV;
1013 name = "tun%d";
1014 } else if (ifr->ifr_flags & IFF_TAP) {
1015 /* TAP device */
1016 flags |= TUN_TAP_DEV;
1017 name = "tap%d";
1018 } else
1019 return -EINVAL;
1020
1021 if (*ifr->ifr_name)
1022 name = ifr->ifr_name;
1023
1024 dev = alloc_netdev(sizeof(struct tun_struct), name,
1025 tun_setup);
1026 if (!dev)
1027 return -ENOMEM;
1028
1029 dev_net_set(dev, net);
1030 dev->rtnl_link_ops = &tun_link_ops;
1031
1032 tun = netdev_priv(dev);
1033 tun->dev = dev;
1034 tun->flags = flags;
1035 tun->txflt.count = 0;
1036
1037 err = -ENOMEM;
1038 sk = sk_alloc(net, AF_UNSPEC, GFP_KERNEL, &tun_proto);
1039 if (!sk)
1040 goto err_free_dev;
1041
1042 init_waitqueue_head(&tun->socket.wait);
1043 tun->socket.ops = &tun_socket_ops;
1044 sock_init_data(&tun->socket, sk);
1045 sk->sk_write_space = tun_sock_write_space;
1046 sk->sk_sndbuf = INT_MAX;
1047
1048 tun_sk(sk)->tun = tun;
1049
1050 security_tun_dev_post_create(sk);
1051
1052 tun_net_init(dev);
1053
1054 if (strchr(dev->name, '%')) {
1055 err = dev_alloc_name(dev, dev->name);
1056 if (err < 0)
1057 goto err_free_sk;
1058 }
1059
1060 err = register_netdevice(tun->dev);
1061 if (err < 0)
1062 goto err_free_sk;
1063
1064 if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) ||
1065 device_create_file(&tun->dev->dev, &dev_attr_owner) ||
1066 device_create_file(&tun->dev->dev, &dev_attr_group))
1067 printk(KERN_ERR "Failed to create tun sysfs files\n");
1068
1069 sk->sk_destruct = tun_sock_destruct;
1070
1071 err = tun_attach(tun, file);
1072 if (err < 0)
1073 goto failed;
1074 }
1075
1076 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
1077
1078 if (ifr->ifr_flags & IFF_NO_PI)
1079 tun->flags |= TUN_NO_PI;
1080 else
1081 tun->flags &= ~TUN_NO_PI;
1082
1083 if (ifr->ifr_flags & IFF_ONE_QUEUE)
1084 tun->flags |= TUN_ONE_QUEUE;
1085 else
1086 tun->flags &= ~TUN_ONE_QUEUE;
1087
1088 if (ifr->ifr_flags & IFF_VNET_HDR)
1089 tun->flags |= TUN_VNET_HDR;
1090 else
1091 tun->flags &= ~TUN_VNET_HDR;
1092
1093 /* Make sure persistent devices do not get stuck in
1094 * xoff state.
1095 */
1096 if (netif_running(tun->dev))
1097 netif_wake_queue(tun->dev);
1098
1099 strcpy(ifr->ifr_name, tun->dev->name);
1100 return 0;
1101
1102 err_free_sk:
1103 sock_put(sk);
1104 err_free_dev:
1105 free_netdev(dev);
1106 failed:
1107 return err;
1108 }
1109
1110 static int tun_get_iff(struct net *net, struct tun_struct *tun,
1111 struct ifreq *ifr)
1112 {
1113 DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
1114
1115 strcpy(ifr->ifr_name, tun->dev->name);
1116
1117 ifr->ifr_flags = tun_flags(tun);
1118
1119 return 0;
1120 }
1121
1122 /* This is like a cut-down ethtool ops, except done via tun fd so no
1123 * privs required. */
1124 static int set_offload(struct net_device *dev, unsigned long arg)
1125 {
1126 unsigned int old_features, features;
1127
1128 old_features = dev->features;
1129 /* Unset features, set them as we chew on the arg. */
1130 features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
1131 |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6
1132 |NETIF_F_UFO));
1133
1134 if (arg & TUN_F_CSUM) {
1135 features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1136 arg &= ~TUN_F_CSUM;
1137
1138 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
1139 if (arg & TUN_F_TSO_ECN) {
1140 features |= NETIF_F_TSO_ECN;
1141 arg &= ~TUN_F_TSO_ECN;
1142 }
1143 if (arg & TUN_F_TSO4)
1144 features |= NETIF_F_TSO;
1145 if (arg & TUN_F_TSO6)
1146 features |= NETIF_F_TSO6;
1147 arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
1148 }
1149
1150 if (arg & TUN_F_UFO) {
1151 features |= NETIF_F_UFO;
1152 arg &= ~TUN_F_UFO;
1153 }
1154 }
1155
1156 /* This gives the user a way to test for new features in future by
1157 * trying to set them. */
1158 if (arg)
1159 return -EINVAL;
1160
1161 dev->features = features;
1162 if (old_features != dev->features)
1163 netdev_features_change(dev);
1164
1165 return 0;
1166 }
1167
1168 static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
1169 unsigned long arg, int ifreq_len)
1170 {
1171 struct tun_file *tfile = file->private_data;
1172 struct tun_struct *tun;
1173 void __user* argp = (void __user*)arg;
1174 struct sock_fprog fprog;
1175 struct ifreq ifr;
1176 int sndbuf;
1177 int ret;
1178
1179 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
1180 if (copy_from_user(&ifr, argp, ifreq_len))
1181 return -EFAULT;
1182
1183 if (cmd == TUNGETFEATURES) {
1184 /* Currently this just means: "what IFF flags are valid?".
1185 * This is needed because we never checked for invalid flags on
1186 * TUNSETIFF. */
1187 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
1188 IFF_VNET_HDR,
1189 (unsigned int __user*)argp);
1190 }
1191
1192 rtnl_lock();
1193
1194 tun = __tun_get(tfile);
1195 if (cmd == TUNSETIFF && !tun) {
1196 ifr.ifr_name[IFNAMSIZ-1] = '\0';
1197
1198 ret = tun_set_iff(tfile->net, file, &ifr);
1199
1200 if (ret)
1201 goto unlock;
1202
1203 if (copy_to_user(argp, &ifr, ifreq_len))
1204 ret = -EFAULT;
1205 goto unlock;
1206 }
1207
1208 ret = -EBADFD;
1209 if (!tun)
1210 goto unlock;
1211
1212 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
1213
1214 ret = 0;
1215 switch (cmd) {
1216 case TUNGETIFF:
1217 ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
1218 if (ret)
1219 break;
1220
1221 if (copy_to_user(argp, &ifr, ifreq_len))
1222 ret = -EFAULT;
1223 break;
1224
1225 case TUNSETNOCSUM:
1226 /* Disable/Enable checksum */
1227 if (arg)
1228 tun->flags |= TUN_NOCHECKSUM;
1229 else
1230 tun->flags &= ~TUN_NOCHECKSUM;
1231
1232 DBG(KERN_INFO "%s: checksum %s\n",
1233 tun->dev->name, arg ? "disabled" : "enabled");
1234 break;
1235
1236 case TUNSETPERSIST:
1237 /* Disable/Enable persist mode */
1238 if (arg)
1239 tun->flags |= TUN_PERSIST;
1240 else
1241 tun->flags &= ~TUN_PERSIST;
1242
1243 DBG(KERN_INFO "%s: persist %s\n",
1244 tun->dev->name, arg ? "enabled" : "disabled");
1245 break;
1246
1247 case TUNSETOWNER:
1248 /* Set owner of the device */
1249 tun->owner = (uid_t) arg;
1250
1251 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
1252 break;
1253
1254 case TUNSETGROUP:
1255 /* Set group of the device */
1256 tun->group= (gid_t) arg;
1257
1258 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
1259 break;
1260
1261 case TUNSETLINK:
1262 /* Only allow setting the type when the interface is down */
1263 if (tun->dev->flags & IFF_UP) {
1264 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
1265 tun->dev->name);
1266 ret = -EBUSY;
1267 } else {
1268 tun->dev->type = (int) arg;
1269 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
1270 ret = 0;
1271 }
1272 break;
1273
1274 #ifdef TUN_DEBUG
1275 case TUNSETDEBUG:
1276 tun->debug = arg;
1277 break;
1278 #endif
1279 case TUNSETOFFLOAD:
1280 ret = set_offload(tun->dev, arg);
1281 break;
1282
1283 case TUNSETTXFILTER:
1284 /* Can be set only for TAPs */
1285 ret = -EINVAL;
1286 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1287 break;
1288 ret = update_filter(&tun->txflt, (void __user *)arg);
1289 break;
1290
1291 case SIOCGIFHWADDR:
1292 /* Get hw addres */
1293 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1294 ifr.ifr_hwaddr.sa_family = tun->dev->type;
1295 if (copy_to_user(argp, &ifr, ifreq_len))
1296 ret = -EFAULT;
1297 break;
1298
1299 case SIOCSIFHWADDR:
1300 /* Set hw address */
1301 DBG(KERN_DEBUG "%s: set hw address: %pM\n",
1302 tun->dev->name, ifr.ifr_hwaddr.sa_data);
1303
1304 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
1305 break;
1306
1307 case TUNGETSNDBUF:
1308 sndbuf = tun->socket.sk->sk_sndbuf;
1309 if (copy_to_user(argp, &sndbuf, sizeof(sndbuf)))
1310 ret = -EFAULT;
1311 break;
1312
1313 case TUNSETSNDBUF:
1314 if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) {
1315 ret = -EFAULT;
1316 break;
1317 }
1318
1319 tun->socket.sk->sk_sndbuf = sndbuf;
1320 break;
1321
1322 case TUNATTACHFILTER:
1323 /* Can be set only for TAPs */
1324 ret = -EINVAL;
1325 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1326 break;
1327 ret = -EFAULT;
1328 if (copy_from_user(&fprog, argp, sizeof(fprog)))
1329 break;
1330
1331 ret = sk_attach_filter(&fprog, tun->socket.sk);
1332 break;
1333
1334 case TUNDETACHFILTER:
1335 /* Can be set only for TAPs */
1336 ret = -EINVAL;
1337 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1338 break;
1339 ret = sk_detach_filter(tun->socket.sk);
1340 break;
1341
1342 default:
1343 ret = -EINVAL;
1344 break;
1345 };
1346
1347 unlock:
1348 rtnl_unlock();
1349 if (tun)
1350 tun_put(tun);
1351 return ret;
1352 }
1353
1354 static long tun_chr_ioctl(struct file *file,
1355 unsigned int cmd, unsigned long arg)
1356 {
1357 return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq));
1358 }
1359
1360 #ifdef CONFIG_COMPAT
1361 static long tun_chr_compat_ioctl(struct file *file,
1362 unsigned int cmd, unsigned long arg)
1363 {
1364 switch (cmd) {
1365 case TUNSETIFF:
1366 case TUNGETIFF:
1367 case TUNSETTXFILTER:
1368 case TUNGETSNDBUF:
1369 case TUNSETSNDBUF:
1370 case SIOCGIFHWADDR:
1371 case SIOCSIFHWADDR:
1372 arg = (unsigned long)compat_ptr(arg);
1373 break;
1374 default:
1375 arg = (compat_ulong_t)arg;
1376 break;
1377 }
1378
1379 /*
1380 * compat_ifreq is shorter than ifreq, so we must not access beyond
1381 * the end of that structure. All fields that are used in this
1382 * driver are compatible though, we don't need to convert the
1383 * contents.
1384 */
1385 return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq));
1386 }
1387 #endif /* CONFIG_COMPAT */
1388
1389 static int tun_chr_fasync(int fd, struct file *file, int on)
1390 {
1391 struct tun_struct *tun = tun_get(file);
1392 int ret;
1393
1394 if (!tun)
1395 return -EBADFD;
1396
1397 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
1398
1399 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
1400 goto out;
1401
1402 if (on) {
1403 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
1404 if (ret)
1405 goto out;
1406 tun->flags |= TUN_FASYNC;
1407 } else
1408 tun->flags &= ~TUN_FASYNC;
1409 ret = 0;
1410 out:
1411 tun_put(tun);
1412 return ret;
1413 }
1414
1415 static int tun_chr_open(struct inode *inode, struct file * file)
1416 {
1417 struct tun_file *tfile;
1418
1419 DBG1(KERN_INFO "tunX: tun_chr_open\n");
1420
1421 tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
1422 if (!tfile)
1423 return -ENOMEM;
1424 atomic_set(&tfile->count, 0);
1425 tfile->tun = NULL;
1426 tfile->net = get_net(current->nsproxy->net_ns);
1427 file->private_data = tfile;
1428 return 0;
1429 }
1430
1431 static int tun_chr_close(struct inode *inode, struct file *file)
1432 {
1433 struct tun_file *tfile = file->private_data;
1434 struct tun_struct *tun;
1435
1436 tun = __tun_get(tfile);
1437 if (tun) {
1438 struct net_device *dev = tun->dev;
1439
1440 DBG(KERN_INFO "%s: tun_chr_close\n", dev->name);
1441
1442 __tun_detach(tun);
1443
1444 /* If desirable, unregister the netdevice. */
1445 if (!(tun->flags & TUN_PERSIST)) {
1446 rtnl_lock();
1447 if (dev->reg_state == NETREG_REGISTERED)
1448 unregister_netdevice(dev);
1449 rtnl_unlock();
1450 }
1451 }
1452
1453 tun = tfile->tun;
1454 if (tun)
1455 sock_put(tun->socket.sk);
1456
1457 put_net(tfile->net);
1458 kfree(tfile);
1459
1460 return 0;
1461 }
1462
1463 static const struct file_operations tun_fops = {
1464 .owner = THIS_MODULE,
1465 .llseek = no_llseek,
1466 .read = do_sync_read,
1467 .aio_read = tun_chr_aio_read,
1468 .write = do_sync_write,
1469 .aio_write = tun_chr_aio_write,
1470 .poll = tun_chr_poll,
1471 .unlocked_ioctl = tun_chr_ioctl,
1472 #ifdef CONFIG_COMPAT
1473 .compat_ioctl = tun_chr_compat_ioctl,
1474 #endif
1475 .open = tun_chr_open,
1476 .release = tun_chr_close,
1477 .fasync = tun_chr_fasync
1478 };
1479
1480 static struct miscdevice tun_miscdev = {
1481 .minor = TUN_MINOR,
1482 .name = "tun",
1483 .nodename = "net/tun",
1484 .fops = &tun_fops,
1485 };
1486
1487 /* ethtool interface */
1488
1489 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1490 {
1491 cmd->supported = 0;
1492 cmd->advertising = 0;
1493 cmd->speed = SPEED_10;
1494 cmd->duplex = DUPLEX_FULL;
1495 cmd->port = PORT_TP;
1496 cmd->phy_address = 0;
1497 cmd->transceiver = XCVR_INTERNAL;
1498 cmd->autoneg = AUTONEG_DISABLE;
1499 cmd->maxtxpkt = 0;
1500 cmd->maxrxpkt = 0;
1501 return 0;
1502 }
1503
1504 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1505 {
1506 struct tun_struct *tun = netdev_priv(dev);
1507
1508 strcpy(info->driver, DRV_NAME);
1509 strcpy(info->version, DRV_VERSION);
1510 strcpy(info->fw_version, "N/A");
1511
1512 switch (tun->flags & TUN_TYPE_MASK) {
1513 case TUN_TUN_DEV:
1514 strcpy(info->bus_info, "tun");
1515 break;
1516 case TUN_TAP_DEV:
1517 strcpy(info->bus_info, "tap");
1518 break;
1519 }
1520 }
1521
1522 static u32 tun_get_msglevel(struct net_device *dev)
1523 {
1524 #ifdef TUN_DEBUG
1525 struct tun_struct *tun = netdev_priv(dev);
1526 return tun->debug;
1527 #else
1528 return -EOPNOTSUPP;
1529 #endif
1530 }
1531
1532 static void tun_set_msglevel(struct net_device *dev, u32 value)
1533 {
1534 #ifdef TUN_DEBUG
1535 struct tun_struct *tun = netdev_priv(dev);
1536 tun->debug = value;
1537 #endif
1538 }
1539
1540 static u32 tun_get_link(struct net_device *dev)
1541 {
1542 struct tun_struct *tun = netdev_priv(dev);
1543 return !!tun->tfile;
1544 }
1545
1546 static u32 tun_get_rx_csum(struct net_device *dev)
1547 {
1548 struct tun_struct *tun = netdev_priv(dev);
1549 return (tun->flags & TUN_NOCHECKSUM) == 0;
1550 }
1551
1552 static int tun_set_rx_csum(struct net_device *dev, u32 data)
1553 {
1554 struct tun_struct *tun = netdev_priv(dev);
1555 if (data)
1556 tun->flags &= ~TUN_NOCHECKSUM;
1557 else
1558 tun->flags |= TUN_NOCHECKSUM;
1559 return 0;
1560 }
1561
1562 static const struct ethtool_ops tun_ethtool_ops = {
1563 .get_settings = tun_get_settings,
1564 .get_drvinfo = tun_get_drvinfo,
1565 .get_msglevel = tun_get_msglevel,
1566 .set_msglevel = tun_set_msglevel,
1567 .get_link = tun_get_link,
1568 .get_rx_csum = tun_get_rx_csum,
1569 .set_rx_csum = tun_set_rx_csum
1570 };
1571
1572
1573 static int __init tun_init(void)
1574 {
1575 int ret = 0;
1576
1577 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1578 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
1579
1580 ret = rtnl_link_register(&tun_link_ops);
1581 if (ret) {
1582 printk(KERN_ERR "tun: Can't register link_ops\n");
1583 goto err_linkops;
1584 }
1585
1586 ret = misc_register(&tun_miscdev);
1587 if (ret) {
1588 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
1589 goto err_misc;
1590 }
1591 return 0;
1592 err_misc:
1593 rtnl_link_unregister(&tun_link_ops);
1594 err_linkops:
1595 return ret;
1596 }
1597
1598 static void tun_cleanup(void)
1599 {
1600 misc_deregister(&tun_miscdev);
1601 rtnl_link_unregister(&tun_link_ops);
1602 }
1603
1604 /* Get an underlying socket object from tun file. Returns error unless file is
1605 * attached to a device. The returned object works like a packet socket, it
1606 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1607 * holding a reference to the file for as long as the socket is in use. */
1608 struct socket *tun_get_socket(struct file *file)
1609 {
1610 struct tun_struct *tun;
1611 if (file->f_op != &tun_fops)
1612 return ERR_PTR(-EINVAL);
1613 tun = tun_get(file);
1614 if (!tun)
1615 return ERR_PTR(-EBADFD);
1616 tun_put(tun);
1617 return &tun->socket;
1618 }
1619 EXPORT_SYMBOL_GPL(tun_get_socket);
1620
1621 module_init(tun_init);
1622 module_exit(tun_cleanup);
1623 MODULE_DESCRIPTION(DRV_DESCRIPTION);
1624 MODULE_AUTHOR(DRV_COPYRIGHT);
1625 MODULE_LICENSE("GPL");
1626 MODULE_ALIAS_MISCDEV(TUN_MINOR);
Linux with added FPC-III support