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firewire: sbp2: fix stall with "Unsolicited response"
[firewire-audio.git] / drivers / net / tun.c
blob63042596f0cf34962afe9c25133e27b0aa746701
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 struct socket_wq wq;
113
114 int vnet_hdr_sz;
115
116 #ifdef TUN_DEBUG
117 int debug;
118 #endif
119 };
120
121 struct tun_sock {
122 struct sock sk;
123 struct tun_struct *tun;
124 };
125
126 static inline struct tun_sock *tun_sk(struct sock *sk)
127 {
128 return container_of(sk, struct tun_sock, sk);
129 }
130
131 static int tun_attach(struct tun_struct *tun, struct file *file)
132 {
133 struct tun_file *tfile = file->private_data;
134 int err;
135
136 ASSERT_RTNL();
137
138 netif_tx_lock_bh(tun->dev);
139
140 err = -EINVAL;
141 if (tfile->tun)
142 goto out;
143
144 err = -EBUSY;
145 if (tun->tfile)
146 goto out;
147
148 err = 0;
149 tfile->tun = tun;
150 tun->tfile = tfile;
151 tun->socket.file = file;
152 dev_hold(tun->dev);
153 sock_hold(tun->socket.sk);
154 atomic_inc(&tfile->count);
155
156 out:
157 netif_tx_unlock_bh(tun->dev);
158 return err;
159 }
160
161 static void __tun_detach(struct tun_struct *tun)
162 {
163 /* Detach from net device */
164 netif_tx_lock_bh(tun->dev);
165 tun->tfile = NULL;
166 tun->socket.file = NULL;
167 netif_tx_unlock_bh(tun->dev);
168
169 /* Drop read queue */
170 skb_queue_purge(&tun->socket.sk->sk_receive_queue);
171
172 /* Drop the extra count on the net device */
173 dev_put(tun->dev);
174 }
175
176 static void tun_detach(struct tun_struct *tun)
177 {
178 rtnl_lock();
179 __tun_detach(tun);
180 rtnl_unlock();
181 }
182
183 static struct tun_struct *__tun_get(struct tun_file *tfile)
184 {
185 struct tun_struct *tun = NULL;
186
187 if (atomic_inc_not_zero(&tfile->count))
188 tun = tfile->tun;
189
190 return tun;
191 }
192
193 static struct tun_struct *tun_get(struct file *file)
194 {
195 return __tun_get(file->private_data);
196 }
197
198 static void tun_put(struct tun_struct *tun)
199 {
200 struct tun_file *tfile = tun->tfile;
201
202 if (atomic_dec_and_test(&tfile->count))
203 tun_detach(tfile->tun);
204 }
205
206 /* TAP filterting */
207 static void addr_hash_set(u32 *mask, const u8 *addr)
208 {
209 int n = ether_crc(ETH_ALEN, addr) >> 26;
210 mask[n >> 5] |= (1 << (n & 31));
211 }
212
213 static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
214 {
215 int n = ether_crc(ETH_ALEN, addr) >> 26;
216 return mask[n >> 5] & (1 << (n & 31));
217 }
218
219 static int update_filter(struct tap_filter *filter, void __user *arg)
220 {
221 struct { u8 u[ETH_ALEN]; } *addr;
222 struct tun_filter uf;
223 int err, alen, n, nexact;
224
225 if (copy_from_user(&uf, arg, sizeof(uf)))
226 return -EFAULT;
227
228 if (!uf.count) {
229 /* Disabled */
230 filter->count = 0;
231 return 0;
232 }
233
234 alen = ETH_ALEN * uf.count;
235 addr = kmalloc(alen, GFP_KERNEL);
236 if (!addr)
237 return -ENOMEM;
238
239 if (copy_from_user(addr, arg + sizeof(uf), alen)) {
240 err = -EFAULT;
241 goto done;
242 }
243
244 /* The filter is updated without holding any locks. Which is
245 * perfectly safe. We disable it first and in the worst
246 * case we'll accept a few undesired packets. */
247 filter->count = 0;
248 wmb();
249
250 /* Use first set of addresses as an exact filter */
251 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
252 memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
253
254 nexact = n;
255
256 /* Remaining multicast addresses are hashed,
257 * unicast will leave the filter disabled. */
258 memset(filter->mask, 0, sizeof(filter->mask));
259 for (; n < uf.count; n++) {
260 if (!is_multicast_ether_addr(addr[n].u)) {
261 err = 0; /* no filter */
262 goto done;
263 }
264 addr_hash_set(filter->mask, addr[n].u);
265 }
266
267 /* For ALLMULTI just set the mask to all ones.
268 * This overrides the mask populated above. */
269 if ((uf.flags & TUN_FLT_ALLMULTI))
270 memset(filter->mask, ~0, sizeof(filter->mask));
271
272 /* Now enable the filter */
273 wmb();
274 filter->count = nexact;
275
276 /* Return the number of exact filters */
277 err = nexact;
278
279 done:
280 kfree(addr);
281 return err;
282 }
283
284 /* Returns: 0 - drop, !=0 - accept */
285 static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
286 {
287 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
288 * at this point. */
289 struct ethhdr *eh = (struct ethhdr *) skb->data;
290 int i;
291
292 /* Exact match */
293 for (i = 0; i < filter->count; i++)
294 if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
295 return 1;
296
297 /* Inexact match (multicast only) */
298 if (is_multicast_ether_addr(eh->h_dest))
299 return addr_hash_test(filter->mask, eh->h_dest);
300
301 return 0;
302 }
303
304 /*
305 * Checks whether the packet is accepted or not.
306 * Returns: 0 - drop, !=0 - accept
307 */
308 static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
309 {
310 if (!filter->count)
311 return 1;
312
313 return run_filter(filter, skb);
314 }
315
316 /* Network device part of the driver */
317
318 static const struct ethtool_ops tun_ethtool_ops;
319
320 /* Net device detach from fd. */
321 static void tun_net_uninit(struct net_device *dev)
322 {
323 struct tun_struct *tun = netdev_priv(dev);
324 struct tun_file *tfile = tun->tfile;
325
326 /* Inform the methods they need to stop using the dev.
327 */
328 if (tfile) {
329 wake_up_all(&tun->wq.wait);
330 if (atomic_dec_and_test(&tfile->count))
331 __tun_detach(tun);
332 }
333 }
334
335 static void tun_free_netdev(struct net_device *dev)
336 {
337 struct tun_struct *tun = netdev_priv(dev);
338
339 sock_put(tun->socket.sk);
340 }
341
342 /* Net device open. */
343 static int tun_net_open(struct net_device *dev)
344 {
345 netif_start_queue(dev);
346 return 0;
347 }
348
349 /* Net device close. */
350 static int tun_net_close(struct net_device *dev)
351 {
352 netif_stop_queue(dev);
353 return 0;
354 }
355
356 /* Net device start xmit */
357 static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
358 {
359 struct tun_struct *tun = netdev_priv(dev);
360
361 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
362
363 /* Drop packet if interface is not attached */
364 if (!tun->tfile)
365 goto drop;
366
367 /* Drop if the filter does not like it.
368 * This is a noop if the filter is disabled.
369 * Filter can be enabled only for the TAP devices. */
370 if (!check_filter(&tun->txflt, skb))
371 goto drop;
372
373 if (tun->socket.sk->sk_filter &&
374 sk_filter(tun->socket.sk, skb))
375 goto drop;
376
377 if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) {
378 if (!(tun->flags & TUN_ONE_QUEUE)) {
379 /* Normal queueing mode. */
380 /* Packet scheduler handles dropping of further packets. */
381 netif_stop_queue(dev);
382
383 /* We won't see all dropped packets individually, so overrun
384 * error is more appropriate. */
385 dev->stats.tx_fifo_errors++;
386 } else {
387 /* Single queue mode.
388 * Driver handles dropping of all packets itself. */
389 goto drop;
390 }
391 }
392
393 /* Orphan the skb - required as we might hang on to it
394 * for indefinite time. */
395 skb_orphan(skb);
396
397 /* Enqueue packet */
398 skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb);
399
400 /* Notify and wake up reader process */
401 if (tun->flags & TUN_FASYNC)
402 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
403 wake_up_interruptible_poll(&tun->wq.wait, POLLIN |
404 POLLRDNORM | POLLRDBAND);
405 return NETDEV_TX_OK;
406
407 drop:
408 dev->stats.tx_dropped++;
409 kfree_skb(skb);
410 return NETDEV_TX_OK;
411 }
412
413 static void tun_net_mclist(struct net_device *dev)
414 {
415 /*
416 * This callback is supposed to deal with mc filter in
417 * _rx_ path and has nothing to do with the _tx_ path.
418 * In rx path we always accept everything userspace gives us.
419 */
420 }
421
422 #define MIN_MTU 68
423 #define MAX_MTU 65535
424
425 static int
426 tun_net_change_mtu(struct net_device *dev, int new_mtu)
427 {
428 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
429 return -EINVAL;
430 dev->mtu = new_mtu;
431 return 0;
432 }
433
434 static const struct net_device_ops tun_netdev_ops = {
435 .ndo_uninit = tun_net_uninit,
436 .ndo_open = tun_net_open,
437 .ndo_stop = tun_net_close,
438 .ndo_start_xmit = tun_net_xmit,
439 .ndo_change_mtu = tun_net_change_mtu,
440 };
441
442 static const struct net_device_ops tap_netdev_ops = {
443 .ndo_uninit = tun_net_uninit,
444 .ndo_open = tun_net_open,
445 .ndo_stop = tun_net_close,
446 .ndo_start_xmit = tun_net_xmit,
447 .ndo_change_mtu = tun_net_change_mtu,
448 .ndo_set_multicast_list = tun_net_mclist,
449 .ndo_set_mac_address = eth_mac_addr,
450 .ndo_validate_addr = eth_validate_addr,
451 };
452
453 /* Initialize net device. */
454 static void tun_net_init(struct net_device *dev)
455 {
456 struct tun_struct *tun = netdev_priv(dev);
457
458 switch (tun->flags & TUN_TYPE_MASK) {
459 case TUN_TUN_DEV:
460 dev->netdev_ops = &tun_netdev_ops;
461
462 /* Point-to-Point TUN Device */
463 dev->hard_header_len = 0;
464 dev->addr_len = 0;
465 dev->mtu = 1500;
466
467 /* Zero header length */
468 dev->type = ARPHRD_NONE;
469 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
470 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
471 break;
472
473 case TUN_TAP_DEV:
474 dev->netdev_ops = &tap_netdev_ops;
475 /* Ethernet TAP Device */
476 ether_setup(dev);
477
478 random_ether_addr(dev->dev_addr);
479
480 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
481 break;
482 }
483 }
484
485 /* Character device part */
486
487 /* Poll */
488 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
489 {
490 struct tun_file *tfile = file->private_data;
491 struct tun_struct *tun = __tun_get(tfile);
492 struct sock *sk;
493 unsigned int mask = 0;
494
495 if (!tun)
496 return POLLERR;
497
498 sk = tun->socket.sk;
499
500 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
501
502 poll_wait(file, &tun->wq.wait, wait);
503
504 if (!skb_queue_empty(&sk->sk_receive_queue))
505 mask |= POLLIN | POLLRDNORM;
506
507 if (sock_writeable(sk) ||
508 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
509 sock_writeable(sk)))
510 mask |= POLLOUT | POLLWRNORM;
511
512 if (tun->dev->reg_state != NETREG_REGISTERED)
513 mask = POLLERR;
514
515 tun_put(tun);
516 return mask;
517 }
518
519 /* prepad is the amount to reserve at front. len is length after that.
520 * linear is a hint as to how much to copy (usually headers). */
521 static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
522 size_t prepad, size_t len,
523 size_t linear, int noblock)
524 {
525 struct sock *sk = tun->socket.sk;
526 struct sk_buff *skb;
527 int err;
528
529 sock_update_classid(sk);
530
531 /* Under a page? Don't bother with paged skb. */
532 if (prepad + len < PAGE_SIZE || !linear)
533 linear = len;
534
535 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
536 &err);
537 if (!skb)
538 return ERR_PTR(err);
539
540 skb_reserve(skb, prepad);
541 skb_put(skb, linear);
542 skb->data_len = len - linear;
543 skb->len += len - linear;
544
545 return skb;
546 }
547
548 /* Get packet from user space buffer */
549 static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
550 const struct iovec *iv, size_t count,
551 int noblock)
552 {
553 struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
554 struct sk_buff *skb;
555 size_t len = count, align = 0;
556 struct virtio_net_hdr gso = { 0 };
557 int offset = 0;
558
559 if (!(tun->flags & TUN_NO_PI)) {
560 if ((len -= sizeof(pi)) > count)
561 return -EINVAL;
562
563 if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi)))
564 return -EFAULT;
565 offset += sizeof(pi);
566 }
567
568 if (tun->flags & TUN_VNET_HDR) {
569 if ((len -= tun->vnet_hdr_sz) > count)
570 return -EINVAL;
571
572 if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso)))
573 return -EFAULT;
574
575 if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
576 gso.csum_start + gso.csum_offset + 2 > gso.hdr_len)
577 gso.hdr_len = gso.csum_start + gso.csum_offset + 2;
578
579 if (gso.hdr_len > len)
580 return -EINVAL;
581 offset += tun->vnet_hdr_sz;
582 }
583
584 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
585 align = NET_IP_ALIGN;
586 if (unlikely(len < ETH_HLEN ||
587 (gso.hdr_len && gso.hdr_len < ETH_HLEN)))
588 return -EINVAL;
589 }
590
591 skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock);
592 if (IS_ERR(skb)) {
593 if (PTR_ERR(skb) != -EAGAIN)
594 tun->dev->stats.rx_dropped++;
595 return PTR_ERR(skb);
596 }
597
598 if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) {
599 tun->dev->stats.rx_dropped++;
600 kfree_skb(skb);
601 return -EFAULT;
602 }
603
604 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
605 if (!skb_partial_csum_set(skb, gso.csum_start,
606 gso.csum_offset)) {
607 tun->dev->stats.rx_frame_errors++;
608 kfree_skb(skb);
609 return -EINVAL;
610 }
611 } else if (tun->flags & TUN_NOCHECKSUM)
612 skb->ip_summed = CHECKSUM_UNNECESSARY;
613
614 switch (tun->flags & TUN_TYPE_MASK) {
615 case TUN_TUN_DEV:
616 if (tun->flags & TUN_NO_PI) {
617 switch (skb->data[0] & 0xf0) {
618 case 0x40:
619 pi.proto = htons(ETH_P_IP);
620 break;
621 case 0x60:
622 pi.proto = htons(ETH_P_IPV6);
623 break;
624 default:
625 tun->dev->stats.rx_dropped++;
626 kfree_skb(skb);
627 return -EINVAL;
628 }
629 }
630
631 skb_reset_mac_header(skb);
632 skb->protocol = pi.proto;
633 skb->dev = tun->dev;
634 break;
635 case TUN_TAP_DEV:
636 skb->protocol = eth_type_trans(skb, tun->dev);
637 break;
638 };
639
640 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
641 pr_debug("GSO!\n");
642 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
643 case VIRTIO_NET_HDR_GSO_TCPV4:
644 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
645 break;
646 case VIRTIO_NET_HDR_GSO_TCPV6:
647 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
648 break;
649 case VIRTIO_NET_HDR_GSO_UDP:
650 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
651 break;
652 default:
653 tun->dev->stats.rx_frame_errors++;
654 kfree_skb(skb);
655 return -EINVAL;
656 }
657
658 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
659 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
660
661 skb_shinfo(skb)->gso_size = gso.gso_size;
662 if (skb_shinfo(skb)->gso_size == 0) {
663 tun->dev->stats.rx_frame_errors++;
664 kfree_skb(skb);
665 return -EINVAL;
666 }
667
668 /* Header must be checked, and gso_segs computed. */
669 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
670 skb_shinfo(skb)->gso_segs = 0;
671 }
672
673 netif_rx_ni(skb);
674
675 tun->dev->stats.rx_packets++;
676 tun->dev->stats.rx_bytes += len;
677
678 return count;
679 }
680
681 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
682 unsigned long count, loff_t pos)
683 {
684 struct file *file = iocb->ki_filp;
685 struct tun_struct *tun = tun_get(file);
686 ssize_t result;
687
688 if (!tun)
689 return -EBADFD;
690
691 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
692
693 result = tun_get_user(tun, iv, iov_length(iv, count),
694 file->f_flags & O_NONBLOCK);
695
696 tun_put(tun);
697 return result;
698 }
699
700 /* Put packet to the user space buffer */
701 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
702 struct sk_buff *skb,
703 const struct iovec *iv, int len)
704 {
705 struct tun_pi pi = { 0, skb->protocol };
706 ssize_t total = 0;
707
708 if (!(tun->flags & TUN_NO_PI)) {
709 if ((len -= sizeof(pi)) < 0)
710 return -EINVAL;
711
712 if (len < skb->len) {
713 /* Packet will be striped */
714 pi.flags |= TUN_PKT_STRIP;
715 }
716
717 if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi)))
718 return -EFAULT;
719 total += sizeof(pi);
720 }
721
722 if (tun->flags & TUN_VNET_HDR) {
723 struct virtio_net_hdr gso = { 0 }; /* no info leak */
724 if ((len -= tun->vnet_hdr_sz) < 0)
725 return -EINVAL;
726
727 if (skb_is_gso(skb)) {
728 struct skb_shared_info *sinfo = skb_shinfo(skb);
729
730 /* This is a hint as to how much should be linear. */
731 gso.hdr_len = skb_headlen(skb);
732 gso.gso_size = sinfo->gso_size;
733 if (sinfo->gso_type & SKB_GSO_TCPV4)
734 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
735 else if (sinfo->gso_type & SKB_GSO_TCPV6)
736 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
737 else if (sinfo->gso_type & SKB_GSO_UDP)
738 gso.gso_type = VIRTIO_NET_HDR_GSO_UDP;
739 else {
740 printk(KERN_ERR "tun: unexpected GSO type: "
741 "0x%x, gso_size %d, hdr_len %d\n",
742 sinfo->gso_type, gso.gso_size,
743 gso.hdr_len);
744 print_hex_dump(KERN_ERR, "tun: ",
745 DUMP_PREFIX_NONE,
746 16, 1, skb->head,
747 min((int)gso.hdr_len, 64), true);
748 WARN_ON_ONCE(1);
749 return -EINVAL;
750 }
751 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
752 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
753 } else
754 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
755
756 if (skb->ip_summed == CHECKSUM_PARTIAL) {
757 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
758 gso.csum_start = skb->csum_start - skb_headroom(skb);
759 gso.csum_offset = skb->csum_offset;
760 } /* else everything is zero */
761
762 if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
763 sizeof(gso))))
764 return -EFAULT;
765 total += tun->vnet_hdr_sz;
766 }
767
768 len = min_t(int, skb->len, len);
769
770 skb_copy_datagram_const_iovec(skb, 0, iv, total, len);
771 total += skb->len;
772
773 tun->dev->stats.tx_packets++;
774 tun->dev->stats.tx_bytes += len;
775
776 return total;
777 }
778
779 static ssize_t tun_do_read(struct tun_struct *tun,
780 struct kiocb *iocb, const struct iovec *iv,
781 ssize_t len, int noblock)
782 {
783 DECLARE_WAITQUEUE(wait, current);
784 struct sk_buff *skb;
785 ssize_t ret = 0;
786
787 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
788
789 add_wait_queue(&tun->wq.wait, &wait);
790 while (len) {
791 current->state = TASK_INTERRUPTIBLE;
792
793 /* Read frames from the queue */
794 if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) {
795 if (noblock) {
796 ret = -EAGAIN;
797 break;
798 }
799 if (signal_pending(current)) {
800 ret = -ERESTARTSYS;
801 break;
802 }
803 if (tun->dev->reg_state != NETREG_REGISTERED) {
804 ret = -EIO;
805 break;
806 }
807
808 /* Nothing to read, let's sleep */
809 schedule();
810 continue;
811 }
812 netif_wake_queue(tun->dev);
813
814 ret = tun_put_user(tun, skb, iv, len);
815 kfree_skb(skb);
816 break;
817 }
818
819 current->state = TASK_RUNNING;
820 remove_wait_queue(&tun->wq.wait, &wait);
821
822 return ret;
823 }
824
825 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
826 unsigned long count, loff_t pos)
827 {
828 struct file *file = iocb->ki_filp;
829 struct tun_file *tfile = file->private_data;
830 struct tun_struct *tun = __tun_get(tfile);
831 ssize_t len, ret;
832
833 if (!tun)
834 return -EBADFD;
835 len = iov_length(iv, count);
836 if (len < 0) {
837 ret = -EINVAL;
838 goto out;
839 }
840
841 ret = tun_do_read(tun, iocb, iv, len, file->f_flags & O_NONBLOCK);
842 ret = min_t(ssize_t, ret, len);
843 out:
844 tun_put(tun);
845 return ret;
846 }
847
848 static void tun_setup(struct net_device *dev)
849 {
850 struct tun_struct *tun = netdev_priv(dev);
851
852 tun->owner = -1;
853 tun->group = -1;
854
855 dev->ethtool_ops = &tun_ethtool_ops;
856 dev->destructor = tun_free_netdev;
857 }
858
859 /* Trivial set of netlink ops to allow deleting tun or tap
860 * device with netlink.
861 */
862 static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
863 {
864 return -EINVAL;
865 }
866
867 static struct rtnl_link_ops tun_link_ops __read_mostly = {
868 .kind = DRV_NAME,
869 .priv_size = sizeof(struct tun_struct),
870 .setup = tun_setup,
871 .validate = tun_validate,
872 };
873
874 static void tun_sock_write_space(struct sock *sk)
875 {
876 struct tun_struct *tun;
877 wait_queue_head_t *wqueue;
878
879 if (!sock_writeable(sk))
880 return;
881
882 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
883 return;
884
885 wqueue = sk_sleep(sk);
886 if (wqueue && waitqueue_active(wqueue))
887 wake_up_interruptible_sync_poll(wqueue, POLLOUT |
888 POLLWRNORM | POLLWRBAND);
889
890 tun = tun_sk(sk)->tun;
891 kill_fasync(&tun->fasync, SIGIO, POLL_OUT);
892 }
893
894 static void tun_sock_destruct(struct sock *sk)
895 {
896 free_netdev(tun_sk(sk)->tun->dev);
897 }
898
899 static int tun_sendmsg(struct kiocb *iocb, struct socket *sock,
900 struct msghdr *m, size_t total_len)
901 {
902 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
903 return tun_get_user(tun, m->msg_iov, total_len,
904 m->msg_flags & MSG_DONTWAIT);
905 }
906
907 static int tun_recvmsg(struct kiocb *iocb, struct socket *sock,
908 struct msghdr *m, size_t total_len,
909 int flags)
910 {
911 struct tun_struct *tun = container_of(sock, struct tun_struct, socket);
912 int ret;
913 if (flags & ~(MSG_DONTWAIT|MSG_TRUNC))
914 return -EINVAL;
915 ret = tun_do_read(tun, iocb, m->msg_iov, total_len,
916 flags & MSG_DONTWAIT);
917 if (ret > total_len) {
918 m->msg_flags |= MSG_TRUNC;
919 ret = flags & MSG_TRUNC ? ret : total_len;
920 }
921 return ret;
922 }
923
924 /* Ops structure to mimic raw sockets with tun */
925 static const struct proto_ops tun_socket_ops = {
926 .sendmsg = tun_sendmsg,
927 .recvmsg = tun_recvmsg,
928 };
929
930 static struct proto tun_proto = {
931 .name = "tun",
932 .owner = THIS_MODULE,
933 .obj_size = sizeof(struct tun_sock),
934 };
935
936 static int tun_flags(struct tun_struct *tun)
937 {
938 int flags = 0;
939
940 if (tun->flags & TUN_TUN_DEV)
941 flags |= IFF_TUN;
942 else
943 flags |= IFF_TAP;
944
945 if (tun->flags & TUN_NO_PI)
946 flags |= IFF_NO_PI;
947
948 if (tun->flags & TUN_ONE_QUEUE)
949 flags |= IFF_ONE_QUEUE;
950
951 if (tun->flags & TUN_VNET_HDR)
952 flags |= IFF_VNET_HDR;
953
954 return flags;
955 }
956
957 static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr,
958 char *buf)
959 {
960 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
961 return sprintf(buf, "0x%x\n", tun_flags(tun));
962 }
963
964 static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr,
965 char *buf)
966 {
967 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
968 return sprintf(buf, "%d\n", tun->owner);
969 }
970
971 static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
972 char *buf)
973 {
974 struct tun_struct *tun = netdev_priv(to_net_dev(dev));
975 return sprintf(buf, "%d\n", tun->group);
976 }
977
978 static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
979 static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL);
980 static DEVICE_ATTR(group, 0444, tun_show_group, NULL);
981
982 static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
983 {
984 struct sock *sk;
985 struct tun_struct *tun;
986 struct net_device *dev;
987 int err;
988
989 dev = __dev_get_by_name(net, ifr->ifr_name);
990 if (dev) {
991 const struct cred *cred = current_cred();
992
993 if (ifr->ifr_flags & IFF_TUN_EXCL)
994 return -EBUSY;
995 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
996 tun = netdev_priv(dev);
997 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
998 tun = netdev_priv(dev);
999 else
1000 return -EINVAL;
1001
1002 if (((tun->owner != -1 && cred->euid != tun->owner) ||
1003 (tun->group != -1 && !in_egroup_p(tun->group))) &&
1004 !capable(CAP_NET_ADMIN))
1005 return -EPERM;
1006 err = security_tun_dev_attach(tun->socket.sk);
1007 if (err < 0)
1008 return err;
1009
1010 err = tun_attach(tun, file);
1011 if (err < 0)
1012 return err;
1013 }
1014 else {
1015 char *name;
1016 unsigned long flags = 0;
1017
1018 if (!capable(CAP_NET_ADMIN))
1019 return -EPERM;
1020 err = security_tun_dev_create();
1021 if (err < 0)
1022 return err;
1023
1024 /* Set dev type */
1025 if (ifr->ifr_flags & IFF_TUN) {
1026 /* TUN device */
1027 flags |= TUN_TUN_DEV;
1028 name = "tun%d";
1029 } else if (ifr->ifr_flags & IFF_TAP) {
1030 /* TAP device */
1031 flags |= TUN_TAP_DEV;
1032 name = "tap%d";
1033 } else
1034 return -EINVAL;
1035
1036 if (*ifr->ifr_name)
1037 name = ifr->ifr_name;
1038
1039 dev = alloc_netdev(sizeof(struct tun_struct), name,
1040 tun_setup);
1041 if (!dev)
1042 return -ENOMEM;
1043
1044 dev_net_set(dev, net);
1045 dev->rtnl_link_ops = &tun_link_ops;
1046
1047 tun = netdev_priv(dev);
1048 tun->dev = dev;
1049 tun->flags = flags;
1050 tun->txflt.count = 0;
1051 tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
1052
1053 err = -ENOMEM;
1054 sk = sk_alloc(net, AF_UNSPEC, GFP_KERNEL, &tun_proto);
1055 if (!sk)
1056 goto err_free_dev;
1057
1058 tun->socket.wq = &tun->wq;
1059 init_waitqueue_head(&tun->wq.wait);
1060 tun->socket.ops = &tun_socket_ops;
1061 sock_init_data(&tun->socket, sk);
1062 sk->sk_write_space = tun_sock_write_space;
1063 sk->sk_sndbuf = INT_MAX;
1064
1065 tun_sk(sk)->tun = tun;
1066
1067 security_tun_dev_post_create(sk);
1068
1069 tun_net_init(dev);
1070
1071 if (strchr(dev->name, '%')) {
1072 err = dev_alloc_name(dev, dev->name);
1073 if (err < 0)
1074 goto err_free_sk;
1075 }
1076
1077 err = register_netdevice(tun->dev);
1078 if (err < 0)
1079 goto err_free_sk;
1080
1081 if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) ||
1082 device_create_file(&tun->dev->dev, &dev_attr_owner) ||
1083 device_create_file(&tun->dev->dev, &dev_attr_group))
1084 printk(KERN_ERR "Failed to create tun sysfs files\n");
1085
1086 sk->sk_destruct = tun_sock_destruct;
1087
1088 err = tun_attach(tun, file);
1089 if (err < 0)
1090 goto failed;
1091 }
1092
1093 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
1094
1095 if (ifr->ifr_flags & IFF_NO_PI)
1096 tun->flags |= TUN_NO_PI;
1097 else
1098 tun->flags &= ~TUN_NO_PI;
1099
1100 if (ifr->ifr_flags & IFF_ONE_QUEUE)
1101 tun->flags |= TUN_ONE_QUEUE;
1102 else
1103 tun->flags &= ~TUN_ONE_QUEUE;
1104
1105 if (ifr->ifr_flags & IFF_VNET_HDR)
1106 tun->flags |= TUN_VNET_HDR;
1107 else
1108 tun->flags &= ~TUN_VNET_HDR;
1109
1110 /* Make sure persistent devices do not get stuck in
1111 * xoff state.
1112 */
1113 if (netif_running(tun->dev))
1114 netif_wake_queue(tun->dev);
1115
1116 strcpy(ifr->ifr_name, tun->dev->name);
1117 return 0;
1118
1119 err_free_sk:
1120 sock_put(sk);
1121 err_free_dev:
1122 free_netdev(dev);
1123 failed:
1124 return err;
1125 }
1126
1127 static int tun_get_iff(struct net *net, struct tun_struct *tun,
1128 struct ifreq *ifr)
1129 {
1130 DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
1131
1132 strcpy(ifr->ifr_name, tun->dev->name);
1133
1134 ifr->ifr_flags = tun_flags(tun);
1135
1136 return 0;
1137 }
1138
1139 /* This is like a cut-down ethtool ops, except done via tun fd so no
1140 * privs required. */
1141 static int set_offload(struct net_device *dev, unsigned long arg)
1142 {
1143 unsigned int old_features, features;
1144
1145 old_features = dev->features;
1146 /* Unset features, set them as we chew on the arg. */
1147 features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
1148 |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6
1149 |NETIF_F_UFO));
1150
1151 if (arg & TUN_F_CSUM) {
1152 features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
1153 arg &= ~TUN_F_CSUM;
1154
1155 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
1156 if (arg & TUN_F_TSO_ECN) {
1157 features |= NETIF_F_TSO_ECN;
1158 arg &= ~TUN_F_TSO_ECN;
1159 }
1160 if (arg & TUN_F_TSO4)
1161 features |= NETIF_F_TSO;
1162 if (arg & TUN_F_TSO6)
1163 features |= NETIF_F_TSO6;
1164 arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
1165 }
1166
1167 if (arg & TUN_F_UFO) {
1168 features |= NETIF_F_UFO;
1169 arg &= ~TUN_F_UFO;
1170 }
1171 }
1172
1173 /* This gives the user a way to test for new features in future by
1174 * trying to set them. */
1175 if (arg)
1176 return -EINVAL;
1177
1178 dev->features = features;
1179 if (old_features != dev->features)
1180 netdev_features_change(dev);
1181
1182 return 0;
1183 }
1184
1185 static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
1186 unsigned long arg, int ifreq_len)
1187 {
1188 struct tun_file *tfile = file->private_data;
1189 struct tun_struct *tun;
1190 void __user* argp = (void __user*)arg;
1191 struct sock_fprog fprog;
1192 struct ifreq ifr;
1193 int sndbuf;
1194 int vnet_hdr_sz;
1195 int ret;
1196
1197 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
1198 if (copy_from_user(&ifr, argp, ifreq_len))
1199 return -EFAULT;
1200
1201 if (cmd == TUNGETFEATURES) {
1202 /* Currently this just means: "what IFF flags are valid?".
1203 * This is needed because we never checked for invalid flags on
1204 * TUNSETIFF. */
1205 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
1206 IFF_VNET_HDR,
1207 (unsigned int __user*)argp);
1208 }
1209
1210 rtnl_lock();
1211
1212 tun = __tun_get(tfile);
1213 if (cmd == TUNSETIFF && !tun) {
1214 ifr.ifr_name[IFNAMSIZ-1] = '\0';
1215
1216 ret = tun_set_iff(tfile->net, file, &ifr);
1217
1218 if (ret)
1219 goto unlock;
1220
1221 if (copy_to_user(argp, &ifr, ifreq_len))
1222 ret = -EFAULT;
1223 goto unlock;
1224 }
1225
1226 ret = -EBADFD;
1227 if (!tun)
1228 goto unlock;
1229
1230 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
1231
1232 ret = 0;
1233 switch (cmd) {
1234 case TUNGETIFF:
1235 ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
1236 if (ret)
1237 break;
1238
1239 if (copy_to_user(argp, &ifr, ifreq_len))
1240 ret = -EFAULT;
1241 break;
1242
1243 case TUNSETNOCSUM:
1244 /* Disable/Enable checksum */
1245 if (arg)
1246 tun->flags |= TUN_NOCHECKSUM;
1247 else
1248 tun->flags &= ~TUN_NOCHECKSUM;
1249
1250 DBG(KERN_INFO "%s: checksum %s\n",
1251 tun->dev->name, arg ? "disabled" : "enabled");
1252 break;
1253
1254 case TUNSETPERSIST:
1255 /* Disable/Enable persist mode */
1256 if (arg)
1257 tun->flags |= TUN_PERSIST;
1258 else
1259 tun->flags &= ~TUN_PERSIST;
1260
1261 DBG(KERN_INFO "%s: persist %s\n",
1262 tun->dev->name, arg ? "enabled" : "disabled");
1263 break;
1264
1265 case TUNSETOWNER:
1266 /* Set owner of the device */
1267 tun->owner = (uid_t) arg;
1268
1269 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
1270 break;
1271
1272 case TUNSETGROUP:
1273 /* Set group of the device */
1274 tun->group= (gid_t) arg;
1275
1276 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
1277 break;
1278
1279 case TUNSETLINK:
1280 /* Only allow setting the type when the interface is down */
1281 if (tun->dev->flags & IFF_UP) {
1282 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
1283 tun->dev->name);
1284 ret = -EBUSY;
1285 } else {
1286 tun->dev->type = (int) arg;
1287 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
1288 ret = 0;
1289 }
1290 break;
1291
1292 #ifdef TUN_DEBUG
1293 case TUNSETDEBUG:
1294 tun->debug = arg;
1295 break;
1296 #endif
1297 case TUNSETOFFLOAD:
1298 ret = set_offload(tun->dev, arg);
1299 break;
1300
1301 case TUNSETTXFILTER:
1302 /* Can be set only for TAPs */
1303 ret = -EINVAL;
1304 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1305 break;
1306 ret = update_filter(&tun->txflt, (void __user *)arg);
1307 break;
1308
1309 case SIOCGIFHWADDR:
1310 /* Get hw addres */
1311 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1312 ifr.ifr_hwaddr.sa_family = tun->dev->type;
1313 if (copy_to_user(argp, &ifr, ifreq_len))
1314 ret = -EFAULT;
1315 break;
1316
1317 case SIOCSIFHWADDR:
1318 /* Set hw address */
1319 DBG(KERN_DEBUG "%s: set hw address: %pM\n",
1320 tun->dev->name, ifr.ifr_hwaddr.sa_data);
1321
1322 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
1323 break;
1324
1325 case TUNGETSNDBUF:
1326 sndbuf = tun->socket.sk->sk_sndbuf;
1327 if (copy_to_user(argp, &sndbuf, sizeof(sndbuf)))
1328 ret = -EFAULT;
1329 break;
1330
1331 case TUNSETSNDBUF:
1332 if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) {
1333 ret = -EFAULT;
1334 break;
1335 }
1336
1337 tun->socket.sk->sk_sndbuf = sndbuf;
1338 break;
1339
1340 case TUNGETVNETHDRSZ:
1341 vnet_hdr_sz = tun->vnet_hdr_sz;
1342 if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz)))
1343 ret = -EFAULT;
1344 break;
1345
1346 case TUNSETVNETHDRSZ:
1347 if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) {
1348 ret = -EFAULT;
1349 break;
1350 }
1351 if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) {
1352 ret = -EINVAL;
1353 break;
1354 }
1355
1356 tun->vnet_hdr_sz = vnet_hdr_sz;
1357 break;
1358
1359 case TUNATTACHFILTER:
1360 /* Can be set only for TAPs */
1361 ret = -EINVAL;
1362 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1363 break;
1364 ret = -EFAULT;
1365 if (copy_from_user(&fprog, argp, sizeof(fprog)))
1366 break;
1367
1368 ret = sk_attach_filter(&fprog, tun->socket.sk);
1369 break;
1370
1371 case TUNDETACHFILTER:
1372 /* Can be set only for TAPs */
1373 ret = -EINVAL;
1374 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1375 break;
1376 ret = sk_detach_filter(tun->socket.sk);
1377 break;
1378
1379 default:
1380 ret = -EINVAL;
1381 break;
1382 }
1383
1384 unlock:
1385 rtnl_unlock();
1386 if (tun)
1387 tun_put(tun);
1388 return ret;
1389 }
1390
1391 static long tun_chr_ioctl(struct file *file,
1392 unsigned int cmd, unsigned long arg)
1393 {
1394 return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq));
1395 }
1396
1397 #ifdef CONFIG_COMPAT
1398 static long tun_chr_compat_ioctl(struct file *file,
1399 unsigned int cmd, unsigned long arg)
1400 {
1401 switch (cmd) {
1402 case TUNSETIFF:
1403 case TUNGETIFF:
1404 case TUNSETTXFILTER:
1405 case TUNGETSNDBUF:
1406 case TUNSETSNDBUF:
1407 case SIOCGIFHWADDR:
1408 case SIOCSIFHWADDR:
1409 arg = (unsigned long)compat_ptr(arg);
1410 break;
1411 default:
1412 arg = (compat_ulong_t)arg;
1413 break;
1414 }
1415
1416 /*
1417 * compat_ifreq is shorter than ifreq, so we must not access beyond
1418 * the end of that structure. All fields that are used in this
1419 * driver are compatible though, we don't need to convert the
1420 * contents.
1421 */
1422 return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq));
1423 }
1424 #endif /* CONFIG_COMPAT */
1425
1426 static int tun_chr_fasync(int fd, struct file *file, int on)
1427 {
1428 struct tun_struct *tun = tun_get(file);
1429 int ret;
1430
1431 if (!tun)
1432 return -EBADFD;
1433
1434 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
1435
1436 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
1437 goto out;
1438
1439 if (on) {
1440 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
1441 if (ret)
1442 goto out;
1443 tun->flags |= TUN_FASYNC;
1444 } else
1445 tun->flags &= ~TUN_FASYNC;
1446 ret = 0;
1447 out:
1448 tun_put(tun);
1449 return ret;
1450 }
1451
1452 static int tun_chr_open(struct inode *inode, struct file * file)
1453 {
1454 struct tun_file *tfile;
1455
1456 DBG1(KERN_INFO "tunX: tun_chr_open\n");
1457
1458 tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
1459 if (!tfile)
1460 return -ENOMEM;
1461 atomic_set(&tfile->count, 0);
1462 tfile->tun = NULL;
1463 tfile->net = get_net(current->nsproxy->net_ns);
1464 file->private_data = tfile;
1465 return 0;
1466 }
1467
1468 static int tun_chr_close(struct inode *inode, struct file *file)
1469 {
1470 struct tun_file *tfile = file->private_data;
1471 struct tun_struct *tun;
1472
1473 tun = __tun_get(tfile);
1474 if (tun) {
1475 struct net_device *dev = tun->dev;
1476
1477 DBG(KERN_INFO "%s: tun_chr_close\n", dev->name);
1478
1479 __tun_detach(tun);
1480
1481 /* If desirable, unregister the netdevice. */
1482 if (!(tun->flags & TUN_PERSIST)) {
1483 rtnl_lock();
1484 if (dev->reg_state == NETREG_REGISTERED)
1485 unregister_netdevice(dev);
1486 rtnl_unlock();
1487 }
1488 }
1489
1490 tun = tfile->tun;
1491 if (tun)
1492 sock_put(tun->socket.sk);
1493
1494 put_net(tfile->net);
1495 kfree(tfile);
1496
1497 return 0;
1498 }
1499
1500 static const struct file_operations tun_fops = {
1501 .owner = THIS_MODULE,
1502 .llseek = no_llseek,
1503 .read = do_sync_read,
1504 .aio_read = tun_chr_aio_read,
1505 .write = do_sync_write,
1506 .aio_write = tun_chr_aio_write,
1507 .poll = tun_chr_poll,
1508 .unlocked_ioctl = tun_chr_ioctl,
1509 #ifdef CONFIG_COMPAT
1510 .compat_ioctl = tun_chr_compat_ioctl,
1511 #endif
1512 .open = tun_chr_open,
1513 .release = tun_chr_close,
1514 .fasync = tun_chr_fasync
1515 };
1516
1517 static struct miscdevice tun_miscdev = {
1518 .minor = TUN_MINOR,
1519 .name = "tun",
1520 .nodename = "net/tun",
1521 .fops = &tun_fops,
1522 };
1523
1524 /* ethtool interface */
1525
1526 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1527 {
1528 cmd->supported = 0;
1529 cmd->advertising = 0;
1530 cmd->speed = SPEED_10;
1531 cmd->duplex = DUPLEX_FULL;
1532 cmd->port = PORT_TP;
1533 cmd->phy_address = 0;
1534 cmd->transceiver = XCVR_INTERNAL;
1535 cmd->autoneg = AUTONEG_DISABLE;
1536 cmd->maxtxpkt = 0;
1537 cmd->maxrxpkt = 0;
1538 return 0;
1539 }
1540
1541 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1542 {
1543 struct tun_struct *tun = netdev_priv(dev);
1544
1545 strcpy(info->driver, DRV_NAME);
1546 strcpy(info->version, DRV_VERSION);
1547 strcpy(info->fw_version, "N/A");
1548
1549 switch (tun->flags & TUN_TYPE_MASK) {
1550 case TUN_TUN_DEV:
1551 strcpy(info->bus_info, "tun");
1552 break;
1553 case TUN_TAP_DEV:
1554 strcpy(info->bus_info, "tap");
1555 break;
1556 }
1557 }
1558
1559 static u32 tun_get_msglevel(struct net_device *dev)
1560 {
1561 #ifdef TUN_DEBUG
1562 struct tun_struct *tun = netdev_priv(dev);
1563 return tun->debug;
1564 #else
1565 return -EOPNOTSUPP;
1566 #endif
1567 }
1568
1569 static void tun_set_msglevel(struct net_device *dev, u32 value)
1570 {
1571 #ifdef TUN_DEBUG
1572 struct tun_struct *tun = netdev_priv(dev);
1573 tun->debug = value;
1574 #endif
1575 }
1576
1577 static u32 tun_get_link(struct net_device *dev)
1578 {
1579 struct tun_struct *tun = netdev_priv(dev);
1580 return !!tun->tfile;
1581 }
1582
1583 static u32 tun_get_rx_csum(struct net_device *dev)
1584 {
1585 struct tun_struct *tun = netdev_priv(dev);
1586 return (tun->flags & TUN_NOCHECKSUM) == 0;
1587 }
1588
1589 static int tun_set_rx_csum(struct net_device *dev, u32 data)
1590 {
1591 struct tun_struct *tun = netdev_priv(dev);
1592 if (data)
1593 tun->flags &= ~TUN_NOCHECKSUM;
1594 else
1595 tun->flags |= TUN_NOCHECKSUM;
1596 return 0;
1597 }
1598
1599 static const struct ethtool_ops tun_ethtool_ops = {
1600 .get_settings = tun_get_settings,
1601 .get_drvinfo = tun_get_drvinfo,
1602 .get_msglevel = tun_get_msglevel,
1603 .set_msglevel = tun_set_msglevel,
1604 .get_link = tun_get_link,
1605 .get_rx_csum = tun_get_rx_csum,
1606 .set_rx_csum = tun_set_rx_csum
1607 };
1608
1609
1610 static int __init tun_init(void)
1611 {
1612 int ret = 0;
1613
1614 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1615 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
1616
1617 ret = rtnl_link_register(&tun_link_ops);
1618 if (ret) {
1619 printk(KERN_ERR "tun: Can't register link_ops\n");
1620 goto err_linkops;
1621 }
1622
1623 ret = misc_register(&tun_miscdev);
1624 if (ret) {
1625 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
1626 goto err_misc;
1627 }
1628 return 0;
1629 err_misc:
1630 rtnl_link_unregister(&tun_link_ops);
1631 err_linkops:
1632 return ret;
1633 }
1634
1635 static void tun_cleanup(void)
1636 {
1637 misc_deregister(&tun_miscdev);
1638 rtnl_link_unregister(&tun_link_ops);
1639 }
1640
1641 /* Get an underlying socket object from tun file. Returns error unless file is
1642 * attached to a device. The returned object works like a packet socket, it
1643 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1644 * holding a reference to the file for as long as the socket is in use. */
1645 struct socket *tun_get_socket(struct file *file)
1646 {
1647 struct tun_struct *tun;
1648 if (file->f_op != &tun_fops)
1649 return ERR_PTR(-EINVAL);
1650 tun = tun_get(file);
1651 if (!tun)
1652 return ERR_PTR(-EBADFD);
1653 tun_put(tun);
1654 return &tun->socket;
1655 }
1656 EXPORT_SYMBOL_GPL(tun_get_socket);
1657
1658 module_init(tun_init);
1659 module_exit(tun_cleanup);
1660 MODULE_DESCRIPTION(DRV_DESCRIPTION);
1661 MODULE_AUTHOR(DRV_COPYRIGHT);
1662 MODULE_LICENSE("GPL");
1663 MODULE_ALIAS_MISCDEV(TUN_MINOR);
1664 MODULE_ALIAS("devname:net/tun");
AMDTP streaming driver for the Linux FireWire stack (Juju)