2 * TUN - Universal TUN/TAP device driver.
3 * Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
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.
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.
15 * $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
21 * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
22 * Add TUNSETLINK ioctl to set the link encapsulation
24 * Mark Smith <markzzzsmith@yahoo.com.au>
25 * Use eth_random_addr() for tap MAC address.
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.
33 * Daniel Podlejski <underley@underley.eu.org>
34 * Modifications for 2.3.99-pre5 kernel.
37 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
39 #define DRV_NAME "tun"
40 #define DRV_VERSION "1.6"
41 #define DRV_DESCRIPTION "Universal TUN/TAP device driver"
42 #define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
44 #include <linux/module.h>
45 #include <linux/errno.h>
46 #include <linux/kernel.h>
47 #include <linux/major.h>
48 #include <linux/slab.h>
49 #include <linux/poll.h>
50 #include <linux/fcntl.h>
51 #include <linux/init.h>
52 #include <linux/skbuff.h>
53 #include <linux/netdevice.h>
54 #include <linux/etherdevice.h>
55 #include <linux/miscdevice.h>
56 #include <linux/ethtool.h>
57 #include <linux/rtnetlink.h>
58 #include <linux/compat.h>
60 #include <linux/if_arp.h>
61 #include <linux/if_ether.h>
62 #include <linux/if_tun.h>
63 #include <linux/crc32.h>
64 #include <linux/nsproxy.h>
65 #include <linux/virtio_net.h>
66 #include <linux/rcupdate.h>
67 #include <net/net_namespace.h>
68 #include <net/netns/generic.h>
69 #include <net/rtnetlink.h>
71 #include <net/cls_cgroup.h>
73 #include <asm/uaccess.h>
75 /* Uncomment to enable debugging */
76 /* #define TUN_DEBUG 1 */
81 #define tun_debug(level, tun, fmt, args...) \
84 netdev_printk(level, tun->dev, fmt, ##args); \
86 #define DBG1(level, fmt, args...) \
89 printk(level fmt, ##args); \
92 #define tun_debug(level, tun, fmt, args...) \
95 netdev_printk(level, tun->dev, fmt, ##args); \
97 #define DBG1(level, fmt, args...) \
100 printk(level fmt, ##args); \
104 #define GOODCOPY_LEN 128
106 #define FLT_EXACT_COUNT 8
108 unsigned int count
; /* Number of addrs. Zero means disabled */
109 u32 mask
[2]; /* Mask of the hashed addrs */
110 unsigned char addr
[FLT_EXACT_COUNT
][ETH_ALEN
];
115 struct tun_struct
*tun
;
122 struct tun_file
*tfile
;
127 struct net_device
*dev
;
128 netdev_features_t set_features
;
129 #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
130 NETIF_F_TSO6|NETIF_F_UFO)
131 struct fasync_struct
*fasync
;
133 struct tap_filter txflt
;
134 struct socket socket
;
146 struct tun_struct
*tun
;
149 static inline struct tun_sock
*tun_sk(struct sock
*sk
)
151 return container_of(sk
, struct tun_sock
, sk
);
154 static int tun_attach(struct tun_struct
*tun
, struct file
*file
)
156 struct tun_file
*tfile
= file
->private_data
;
161 netif_tx_lock_bh(tun
->dev
);
174 tun
->socket
.file
= file
;
175 netif_carrier_on(tun
->dev
);
177 sock_hold(tun
->socket
.sk
);
178 atomic_inc(&tfile
->count
);
181 netif_tx_unlock_bh(tun
->dev
);
185 static void __tun_detach(struct tun_struct
*tun
)
187 /* Detach from net device */
188 netif_tx_lock_bh(tun
->dev
);
189 netif_carrier_off(tun
->dev
);
191 netif_tx_unlock_bh(tun
->dev
);
193 /* Drop read queue */
194 skb_queue_purge(&tun
->socket
.sk
->sk_receive_queue
);
196 /* Drop the extra count on the net device */
200 static void tun_detach(struct tun_struct
*tun
)
207 static struct tun_struct
*__tun_get(struct tun_file
*tfile
)
209 struct tun_struct
*tun
= NULL
;
211 if (atomic_inc_not_zero(&tfile
->count
))
217 static struct tun_struct
*tun_get(struct file
*file
)
219 return __tun_get(file
->private_data
);
222 static void tun_put(struct tun_struct
*tun
)
224 struct tun_file
*tfile
= tun
->tfile
;
226 if (atomic_dec_and_test(&tfile
->count
))
227 tun_detach(tfile
->tun
);
231 static void addr_hash_set(u32
*mask
, const u8
*addr
)
233 int n
= ether_crc(ETH_ALEN
, addr
) >> 26;
234 mask
[n
>> 5] |= (1 << (n
& 31));
237 static unsigned int addr_hash_test(const u32
*mask
, const u8
*addr
)
239 int n
= ether_crc(ETH_ALEN
, addr
) >> 26;
240 return mask
[n
>> 5] & (1 << (n
& 31));
243 static int update_filter(struct tap_filter
*filter
, void __user
*arg
)
245 struct { u8 u
[ETH_ALEN
]; } *addr
;
246 struct tun_filter uf
;
247 int err
, alen
, n
, nexact
;
249 if (copy_from_user(&uf
, arg
, sizeof(uf
)))
258 alen
= ETH_ALEN
* uf
.count
;
259 addr
= kmalloc(alen
, GFP_KERNEL
);
263 if (copy_from_user(addr
, arg
+ sizeof(uf
), alen
)) {
268 /* The filter is updated without holding any locks. Which is
269 * perfectly safe. We disable it first and in the worst
270 * case we'll accept a few undesired packets. */
274 /* Use first set of addresses as an exact filter */
275 for (n
= 0; n
< uf
.count
&& n
< FLT_EXACT_COUNT
; n
++)
276 memcpy(filter
->addr
[n
], addr
[n
].u
, ETH_ALEN
);
280 /* Remaining multicast addresses are hashed,
281 * unicast will leave the filter disabled. */
282 memset(filter
->mask
, 0, sizeof(filter
->mask
));
283 for (; n
< uf
.count
; n
++) {
284 if (!is_multicast_ether_addr(addr
[n
].u
)) {
285 err
= 0; /* no filter */
288 addr_hash_set(filter
->mask
, addr
[n
].u
);
291 /* For ALLMULTI just set the mask to all ones.
292 * This overrides the mask populated above. */
293 if ((uf
.flags
& TUN_FLT_ALLMULTI
))
294 memset(filter
->mask
, ~0, sizeof(filter
->mask
));
296 /* Now enable the filter */
298 filter
->count
= nexact
;
300 /* Return the number of exact filters */
308 /* Returns: 0 - drop, !=0 - accept */
309 static int run_filter(struct tap_filter
*filter
, const struct sk_buff
*skb
)
311 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
313 struct ethhdr
*eh
= (struct ethhdr
*) skb
->data
;
317 for (i
= 0; i
< filter
->count
; i
++)
318 if (ether_addr_equal(eh
->h_dest
, filter
->addr
[i
]))
321 /* Inexact match (multicast only) */
322 if (is_multicast_ether_addr(eh
->h_dest
))
323 return addr_hash_test(filter
->mask
, eh
->h_dest
);
329 * Checks whether the packet is accepted or not.
330 * Returns: 0 - drop, !=0 - accept
332 static int check_filter(struct tap_filter
*filter
, const struct sk_buff
*skb
)
337 return run_filter(filter
, skb
);
340 /* Network device part of the driver */
342 static const struct ethtool_ops tun_ethtool_ops
;
344 /* Net device detach from fd. */
345 static void tun_net_uninit(struct net_device
*dev
)
347 struct tun_struct
*tun
= netdev_priv(dev
);
348 struct tun_file
*tfile
= tun
->tfile
;
350 /* Inform the methods they need to stop using the dev.
353 wake_up_all(&tun
->wq
.wait
);
354 if (atomic_dec_and_test(&tfile
->count
))
359 static void tun_free_netdev(struct net_device
*dev
)
361 struct tun_struct
*tun
= netdev_priv(dev
);
363 BUG_ON(!test_bit(SOCK_EXTERNALLY_ALLOCATED
, &tun
->socket
.flags
));
365 sk_release_kernel(tun
->socket
.sk
);
368 /* Net device open. */
369 static int tun_net_open(struct net_device
*dev
)
371 netif_start_queue(dev
);
375 /* Net device close. */
376 static int tun_net_close(struct net_device
*dev
)
378 netif_stop_queue(dev
);
382 /* Net device start xmit */
383 static netdev_tx_t
tun_net_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
385 struct tun_struct
*tun
= netdev_priv(dev
);
387 tun_debug(KERN_INFO
, tun
, "tun_net_xmit %d\n", skb
->len
);
389 /* Drop packet if interface is not attached */
393 /* Drop if the filter does not like it.
394 * This is a noop if the filter is disabled.
395 * Filter can be enabled only for the TAP devices. */
396 if (!check_filter(&tun
->txflt
, skb
))
399 if (tun
->socket
.sk
->sk_filter
&&
400 sk_filter(tun
->socket
.sk
, skb
))
403 if (skb_queue_len(&tun
->socket
.sk
->sk_receive_queue
) >= dev
->tx_queue_len
) {
404 if (!(tun
->flags
& TUN_ONE_QUEUE
)) {
405 /* Normal queueing mode. */
406 /* Packet scheduler handles dropping of further packets. */
407 netif_stop_queue(dev
);
409 /* We won't see all dropped packets individually, so overrun
410 * error is more appropriate. */
411 dev
->stats
.tx_fifo_errors
++;
413 /* Single queue mode.
414 * Driver handles dropping of all packets itself. */
419 /* Orphan the skb - required as we might hang on to it
420 * for indefinite time. */
421 if (unlikely(skb_orphan_frags(skb
, GFP_ATOMIC
)))
426 skb_queue_tail(&tun
->socket
.sk
->sk_receive_queue
, skb
);
428 /* Notify and wake up reader process */
429 if (tun
->flags
& TUN_FASYNC
)
430 kill_fasync(&tun
->fasync
, SIGIO
, POLL_IN
);
431 wake_up_interruptible_poll(&tun
->wq
.wait
, POLLIN
|
432 POLLRDNORM
| POLLRDBAND
);
436 dev
->stats
.tx_dropped
++;
441 static void tun_net_mclist(struct net_device
*dev
)
444 * This callback is supposed to deal with mc filter in
445 * _rx_ path and has nothing to do with the _tx_ path.
446 * In rx path we always accept everything userspace gives us.
451 #define MAX_MTU 65535
454 tun_net_change_mtu(struct net_device
*dev
, int new_mtu
)
456 if (new_mtu
< MIN_MTU
|| new_mtu
+ dev
->hard_header_len
> MAX_MTU
)
462 static netdev_features_t
tun_net_fix_features(struct net_device
*dev
,
463 netdev_features_t features
)
465 struct tun_struct
*tun
= netdev_priv(dev
);
467 return (features
& tun
->set_features
) | (features
& ~TUN_USER_FEATURES
);
469 #ifdef CONFIG_NET_POLL_CONTROLLER
470 static void tun_poll_controller(struct net_device
*dev
)
473 * Tun only receives frames when:
474 * 1) the char device endpoint gets data from user space
475 * 2) the tun socket gets a sendmsg call from user space
476 * Since both of those are syncronous operations, we are guaranteed
477 * never to have pending data when we poll for it
478 * so theres nothing to do here but return.
479 * We need this though so netpoll recognizes us as an interface that
480 * supports polling, which enables bridge devices in virt setups to
481 * still use netconsole
486 static const struct net_device_ops tun_netdev_ops
= {
487 .ndo_uninit
= tun_net_uninit
,
488 .ndo_open
= tun_net_open
,
489 .ndo_stop
= tun_net_close
,
490 .ndo_start_xmit
= tun_net_xmit
,
491 .ndo_change_mtu
= tun_net_change_mtu
,
492 .ndo_fix_features
= tun_net_fix_features
,
493 #ifdef CONFIG_NET_POLL_CONTROLLER
494 .ndo_poll_controller
= tun_poll_controller
,
498 static const struct net_device_ops tap_netdev_ops
= {
499 .ndo_uninit
= tun_net_uninit
,
500 .ndo_open
= tun_net_open
,
501 .ndo_stop
= tun_net_close
,
502 .ndo_start_xmit
= tun_net_xmit
,
503 .ndo_change_mtu
= tun_net_change_mtu
,
504 .ndo_fix_features
= tun_net_fix_features
,
505 .ndo_set_rx_mode
= tun_net_mclist
,
506 .ndo_set_mac_address
= eth_mac_addr
,
507 .ndo_validate_addr
= eth_validate_addr
,
508 #ifdef CONFIG_NET_POLL_CONTROLLER
509 .ndo_poll_controller
= tun_poll_controller
,
513 /* Initialize net device. */
514 static void tun_net_init(struct net_device
*dev
)
516 struct tun_struct
*tun
= netdev_priv(dev
);
518 switch (tun
->flags
& TUN_TYPE_MASK
) {
520 dev
->netdev_ops
= &tun_netdev_ops
;
522 /* Point-to-Point TUN Device */
523 dev
->hard_header_len
= 0;
527 /* Zero header length */
528 dev
->type
= ARPHRD_NONE
;
529 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
530 dev
->tx_queue_len
= TUN_READQ_SIZE
; /* We prefer our own queue length */
534 dev
->netdev_ops
= &tap_netdev_ops
;
535 /* Ethernet TAP Device */
537 dev
->priv_flags
&= ~IFF_TX_SKB_SHARING
;
539 eth_hw_addr_random(dev
);
541 dev
->tx_queue_len
= TUN_READQ_SIZE
; /* We prefer our own queue length */
546 /* Character device part */
549 static unsigned int tun_chr_poll(struct file
*file
, poll_table
* wait
)
551 struct tun_file
*tfile
= file
->private_data
;
552 struct tun_struct
*tun
= __tun_get(tfile
);
554 unsigned int mask
= 0;
561 tun_debug(KERN_INFO
, tun
, "tun_chr_poll\n");
563 poll_wait(file
, &tun
->wq
.wait
, wait
);
565 if (!skb_queue_empty(&sk
->sk_receive_queue
))
566 mask
|= POLLIN
| POLLRDNORM
;
568 if (sock_writeable(sk
) ||
569 (!test_and_set_bit(SOCK_ASYNC_NOSPACE
, &sk
->sk_socket
->flags
) &&
571 mask
|= POLLOUT
| POLLWRNORM
;
573 if (tun
->dev
->reg_state
!= NETREG_REGISTERED
)
580 /* prepad is the amount to reserve at front. len is length after that.
581 * linear is a hint as to how much to copy (usually headers). */
582 static struct sk_buff
*tun_alloc_skb(struct tun_struct
*tun
,
583 size_t prepad
, size_t len
,
584 size_t linear
, int noblock
)
586 struct sock
*sk
= tun
->socket
.sk
;
590 sock_update_classid(sk
);
592 /* Under a page? Don't bother with paged skb. */
593 if (prepad
+ len
< PAGE_SIZE
|| !linear
)
596 skb
= sock_alloc_send_pskb(sk
, prepad
+ linear
, len
- linear
, noblock
,
601 skb_reserve(skb
, prepad
);
602 skb_put(skb
, linear
);
603 skb
->data_len
= len
- linear
;
604 skb
->len
+= len
- linear
;
609 /* set skb frags from iovec, this can move to core network code for reuse */
610 static int zerocopy_sg_from_iovec(struct sk_buff
*skb
, const struct iovec
*from
,
611 int offset
, size_t count
)
613 int len
= iov_length(from
, count
) - offset
;
614 int copy
= skb_headlen(skb
);
615 int size
, offset1
= 0;
618 /* Skip over from offset */
619 while (count
&& (offset
>= from
->iov_len
)) {
620 offset
-= from
->iov_len
;
625 /* copy up to skb headlen */
626 while (count
&& (copy
> 0)) {
627 size
= min_t(unsigned int, copy
, from
->iov_len
- offset
);
628 if (copy_from_user(skb
->data
+ offset1
, from
->iov_base
+ offset
,
645 struct page
*page
[MAX_SKB_FRAGS
];
648 unsigned long truesize
;
650 len
= from
->iov_len
- offset
;
656 base
= (unsigned long)from
->iov_base
+ offset
;
657 size
= ((base
& ~PAGE_MASK
) + len
+ ~PAGE_MASK
) >> PAGE_SHIFT
;
658 if (i
+ size
> MAX_SKB_FRAGS
)
660 num_pages
= get_user_pages_fast(base
, size
, 0, &page
[i
]);
661 if (num_pages
!= size
) {
662 for (i
= 0; i
< num_pages
; i
++)
666 truesize
= size
* PAGE_SIZE
;
667 skb
->data_len
+= len
;
669 skb
->truesize
+= truesize
;
670 atomic_add(truesize
, &skb
->sk
->sk_wmem_alloc
);
672 int off
= base
& ~PAGE_MASK
;
673 int size
= min_t(int, len
, PAGE_SIZE
- off
);
674 __skb_fill_page_desc(skb
, i
, page
[i
], off
, size
);
675 skb_shinfo(skb
)->nr_frags
++;
676 /* increase sk_wmem_alloc */
687 /* Get packet from user space buffer */
688 static ssize_t
tun_get_user(struct tun_struct
*tun
, void *msg_control
,
689 const struct iovec
*iv
, size_t total_len
,
690 size_t count
, int noblock
)
692 struct tun_pi pi
= { 0, cpu_to_be16(ETH_P_IP
) };
694 size_t len
= total_len
, align
= NET_SKB_PAD
;
695 struct virtio_net_hdr gso
= { 0 };
698 bool zerocopy
= false;
701 if (!(tun
->flags
& TUN_NO_PI
)) {
702 if ((len
-= sizeof(pi
)) > total_len
)
705 if (memcpy_fromiovecend((void *)&pi
, iv
, 0, sizeof(pi
)))
707 offset
+= sizeof(pi
);
710 if (tun
->flags
& TUN_VNET_HDR
) {
711 if ((len
-= tun
->vnet_hdr_sz
) > total_len
)
714 if (memcpy_fromiovecend((void *)&gso
, iv
, offset
, sizeof(gso
)))
717 if ((gso
.flags
& VIRTIO_NET_HDR_F_NEEDS_CSUM
) &&
718 gso
.csum_start
+ gso
.csum_offset
+ 2 > gso
.hdr_len
)
719 gso
.hdr_len
= gso
.csum_start
+ gso
.csum_offset
+ 2;
721 if (gso
.hdr_len
> len
)
723 offset
+= tun
->vnet_hdr_sz
;
726 if ((tun
->flags
& TUN_TYPE_MASK
) == TUN_TAP_DEV
) {
727 align
+= NET_IP_ALIGN
;
728 if (unlikely(len
< ETH_HLEN
||
729 (gso
.hdr_len
&& gso
.hdr_len
< ETH_HLEN
)))
737 /* Userspace may produce vectors with count greater than
738 * MAX_SKB_FRAGS, so we need to linearize parts of the skb
739 * to let the rest of data to be fit in the frags.
741 if (count
> MAX_SKB_FRAGS
) {
742 copylen
= iov_length(iv
, count
- MAX_SKB_FRAGS
);
743 if (copylen
< offset
)
749 /* There are 256 bytes to be copied in skb, so there is enough
750 * room for skb expand head in case it is used.
751 * The rest of the buffer is mapped from userspace.
753 if (copylen
< gso
.hdr_len
)
754 copylen
= gso
.hdr_len
;
756 copylen
= GOODCOPY_LEN
;
760 skb
= tun_alloc_skb(tun
, align
, copylen
, gso
.hdr_len
, noblock
);
762 if (PTR_ERR(skb
) != -EAGAIN
)
763 tun
->dev
->stats
.rx_dropped
++;
768 err
= zerocopy_sg_from_iovec(skb
, iv
, offset
, count
);
770 err
= skb_copy_datagram_from_iovec(skb
, 0, iv
, offset
, len
);
773 tun
->dev
->stats
.rx_dropped
++;
778 if (gso
.flags
& VIRTIO_NET_HDR_F_NEEDS_CSUM
) {
779 if (!skb_partial_csum_set(skb
, gso
.csum_start
,
781 tun
->dev
->stats
.rx_frame_errors
++;
787 switch (tun
->flags
& TUN_TYPE_MASK
) {
789 if (tun
->flags
& TUN_NO_PI
) {
790 switch (skb
->data
[0] & 0xf0) {
792 pi
.proto
= htons(ETH_P_IP
);
795 pi
.proto
= htons(ETH_P_IPV6
);
798 tun
->dev
->stats
.rx_dropped
++;
804 skb_reset_mac_header(skb
);
805 skb
->protocol
= pi
.proto
;
809 skb
->protocol
= eth_type_trans(skb
, tun
->dev
);
813 if (gso
.gso_type
!= VIRTIO_NET_HDR_GSO_NONE
) {
815 switch (gso
.gso_type
& ~VIRTIO_NET_HDR_GSO_ECN
) {
816 case VIRTIO_NET_HDR_GSO_TCPV4
:
817 skb_shinfo(skb
)->gso_type
= SKB_GSO_TCPV4
;
819 case VIRTIO_NET_HDR_GSO_TCPV6
:
820 skb_shinfo(skb
)->gso_type
= SKB_GSO_TCPV6
;
822 case VIRTIO_NET_HDR_GSO_UDP
:
823 skb_shinfo(skb
)->gso_type
= SKB_GSO_UDP
;
826 tun
->dev
->stats
.rx_frame_errors
++;
831 if (gso
.gso_type
& VIRTIO_NET_HDR_GSO_ECN
)
832 skb_shinfo(skb
)->gso_type
|= SKB_GSO_TCP_ECN
;
834 skb_shinfo(skb
)->gso_size
= gso
.gso_size
;
835 if (skb_shinfo(skb
)->gso_size
== 0) {
836 tun
->dev
->stats
.rx_frame_errors
++;
841 /* Header must be checked, and gso_segs computed. */
842 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
843 skb_shinfo(skb
)->gso_segs
= 0;
846 /* copy skb_ubuf_info for callback when skb has no error */
848 skb_shinfo(skb
)->destructor_arg
= msg_control
;
849 skb_shinfo(skb
)->tx_flags
|= SKBTX_DEV_ZEROCOPY
;
854 tun
->dev
->stats
.rx_packets
++;
855 tun
->dev
->stats
.rx_bytes
+= len
;
860 static ssize_t
tun_chr_aio_write(struct kiocb
*iocb
, const struct iovec
*iv
,
861 unsigned long count
, loff_t pos
)
863 struct file
*file
= iocb
->ki_filp
;
864 struct tun_struct
*tun
= tun_get(file
);
870 tun_debug(KERN_INFO
, tun
, "tun_chr_write %ld\n", count
);
872 result
= tun_get_user(tun
, NULL
, iv
, iov_length(iv
, count
), count
,
873 file
->f_flags
& O_NONBLOCK
);
879 /* Put packet to the user space buffer */
880 static ssize_t
tun_put_user(struct tun_struct
*tun
,
882 const struct iovec
*iv
, int len
)
884 struct tun_pi pi
= { 0, skb
->protocol
};
887 if (!(tun
->flags
& TUN_NO_PI
)) {
888 if ((len
-= sizeof(pi
)) < 0)
891 if (len
< skb
->len
) {
892 /* Packet will be striped */
893 pi
.flags
|= TUN_PKT_STRIP
;
896 if (memcpy_toiovecend(iv
, (void *) &pi
, 0, sizeof(pi
)))
901 if (tun
->flags
& TUN_VNET_HDR
) {
902 struct virtio_net_hdr gso
= { 0 }; /* no info leak */
903 if ((len
-= tun
->vnet_hdr_sz
) < 0)
906 if (skb_is_gso(skb
)) {
907 struct skb_shared_info
*sinfo
= skb_shinfo(skb
);
909 /* This is a hint as to how much should be linear. */
910 gso
.hdr_len
= skb_headlen(skb
);
911 gso
.gso_size
= sinfo
->gso_size
;
912 if (sinfo
->gso_type
& SKB_GSO_TCPV4
)
913 gso
.gso_type
= VIRTIO_NET_HDR_GSO_TCPV4
;
914 else if (sinfo
->gso_type
& SKB_GSO_TCPV6
)
915 gso
.gso_type
= VIRTIO_NET_HDR_GSO_TCPV6
;
916 else if (sinfo
->gso_type
& SKB_GSO_UDP
)
917 gso
.gso_type
= VIRTIO_NET_HDR_GSO_UDP
;
919 pr_err("unexpected GSO type: "
920 "0x%x, gso_size %d, hdr_len %d\n",
921 sinfo
->gso_type
, gso
.gso_size
,
923 print_hex_dump(KERN_ERR
, "tun: ",
926 min((int)gso
.hdr_len
, 64), true);
930 if (sinfo
->gso_type
& SKB_GSO_TCP_ECN
)
931 gso
.gso_type
|= VIRTIO_NET_HDR_GSO_ECN
;
933 gso
.gso_type
= VIRTIO_NET_HDR_GSO_NONE
;
935 if (skb
->ip_summed
== CHECKSUM_PARTIAL
) {
936 gso
.flags
= VIRTIO_NET_HDR_F_NEEDS_CSUM
;
937 gso
.csum_start
= skb_checksum_start_offset(skb
);
938 gso
.csum_offset
= skb
->csum_offset
;
939 } else if (skb
->ip_summed
== CHECKSUM_UNNECESSARY
) {
940 gso
.flags
= VIRTIO_NET_HDR_F_DATA_VALID
;
941 } /* else everything is zero */
943 if (unlikely(memcpy_toiovecend(iv
, (void *)&gso
, total
,
946 total
+= tun
->vnet_hdr_sz
;
949 len
= min_t(int, skb
->len
, len
);
951 skb_copy_datagram_const_iovec(skb
, 0, iv
, total
, len
);
954 tun
->dev
->stats
.tx_packets
++;
955 tun
->dev
->stats
.tx_bytes
+= len
;
960 static ssize_t
tun_do_read(struct tun_struct
*tun
,
961 struct kiocb
*iocb
, const struct iovec
*iv
,
962 ssize_t len
, int noblock
)
964 DECLARE_WAITQUEUE(wait
, current
);
968 tun_debug(KERN_INFO
, tun
, "tun_chr_read\n");
970 if (unlikely(!noblock
))
971 add_wait_queue(&tun
->wq
.wait
, &wait
);
973 current
->state
= TASK_INTERRUPTIBLE
;
975 /* Read frames from the queue */
976 if (!(skb
=skb_dequeue(&tun
->socket
.sk
->sk_receive_queue
))) {
981 if (signal_pending(current
)) {
985 if (tun
->dev
->reg_state
!= NETREG_REGISTERED
) {
990 /* Nothing to read, let's sleep */
994 netif_wake_queue(tun
->dev
);
996 ret
= tun_put_user(tun
, skb
, iv
, len
);
1001 current
->state
= TASK_RUNNING
;
1002 if (unlikely(!noblock
))
1003 remove_wait_queue(&tun
->wq
.wait
, &wait
);
1008 static ssize_t
tun_chr_aio_read(struct kiocb
*iocb
, const struct iovec
*iv
,
1009 unsigned long count
, loff_t pos
)
1011 struct file
*file
= iocb
->ki_filp
;
1012 struct tun_file
*tfile
= file
->private_data
;
1013 struct tun_struct
*tun
= __tun_get(tfile
);
1018 len
= iov_length(iv
, count
);
1024 ret
= tun_do_read(tun
, iocb
, iv
, len
, file
->f_flags
& O_NONBLOCK
);
1025 ret
= min_t(ssize_t
, ret
, len
);
1031 static void tun_setup(struct net_device
*dev
)
1033 struct tun_struct
*tun
= netdev_priv(dev
);
1035 tun
->owner
= INVALID_UID
;
1036 tun
->group
= INVALID_GID
;
1038 dev
->ethtool_ops
= &tun_ethtool_ops
;
1039 dev
->destructor
= tun_free_netdev
;
1042 /* Trivial set of netlink ops to allow deleting tun or tap
1043 * device with netlink.
1045 static int tun_validate(struct nlattr
*tb
[], struct nlattr
*data
[])
1050 static struct rtnl_link_ops tun_link_ops __read_mostly
= {
1052 .priv_size
= sizeof(struct tun_struct
),
1054 .validate
= tun_validate
,
1057 static void tun_sock_write_space(struct sock
*sk
)
1059 struct tun_struct
*tun
;
1060 wait_queue_head_t
*wqueue
;
1062 if (!sock_writeable(sk
))
1065 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE
, &sk
->sk_socket
->flags
))
1068 wqueue
= sk_sleep(sk
);
1069 if (wqueue
&& waitqueue_active(wqueue
))
1070 wake_up_interruptible_sync_poll(wqueue
, POLLOUT
|
1071 POLLWRNORM
| POLLWRBAND
);
1073 tun
= tun_sk(sk
)->tun
;
1074 kill_fasync(&tun
->fasync
, SIGIO
, POLL_OUT
);
1077 static void tun_sock_destruct(struct sock
*sk
)
1079 free_netdev(tun_sk(sk
)->tun
->dev
);
1082 static int tun_sendmsg(struct kiocb
*iocb
, struct socket
*sock
,
1083 struct msghdr
*m
, size_t total_len
)
1085 struct tun_struct
*tun
= container_of(sock
, struct tun_struct
, socket
);
1086 return tun_get_user(tun
, m
->msg_control
, m
->msg_iov
, total_len
,
1087 m
->msg_iovlen
, m
->msg_flags
& MSG_DONTWAIT
);
1090 static int tun_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1091 struct msghdr
*m
, size_t total_len
,
1094 struct tun_struct
*tun
= container_of(sock
, struct tun_struct
, socket
);
1096 if (flags
& ~(MSG_DONTWAIT
|MSG_TRUNC
))
1098 ret
= tun_do_read(tun
, iocb
, m
->msg_iov
, total_len
,
1099 flags
& MSG_DONTWAIT
);
1100 if (ret
> total_len
) {
1101 m
->msg_flags
|= MSG_TRUNC
;
1102 ret
= flags
& MSG_TRUNC
? ret
: total_len
;
1107 static int tun_release(struct socket
*sock
)
1114 /* Ops structure to mimic raw sockets with tun */
1115 static const struct proto_ops tun_socket_ops
= {
1116 .sendmsg
= tun_sendmsg
,
1117 .recvmsg
= tun_recvmsg
,
1118 .release
= tun_release
,
1121 static struct proto tun_proto
= {
1123 .owner
= THIS_MODULE
,
1124 .obj_size
= sizeof(struct tun_sock
),
1127 static int tun_flags(struct tun_struct
*tun
)
1131 if (tun
->flags
& TUN_TUN_DEV
)
1136 if (tun
->flags
& TUN_NO_PI
)
1139 if (tun
->flags
& TUN_ONE_QUEUE
)
1140 flags
|= IFF_ONE_QUEUE
;
1142 if (tun
->flags
& TUN_VNET_HDR
)
1143 flags
|= IFF_VNET_HDR
;
1148 static ssize_t
tun_show_flags(struct device
*dev
, struct device_attribute
*attr
,
1151 struct tun_struct
*tun
= netdev_priv(to_net_dev(dev
));
1152 return sprintf(buf
, "0x%x\n", tun_flags(tun
));
1155 static ssize_t
tun_show_owner(struct device
*dev
, struct device_attribute
*attr
,
1158 struct tun_struct
*tun
= netdev_priv(to_net_dev(dev
));
1159 return uid_valid(tun
->owner
)?
1160 sprintf(buf
, "%u\n",
1161 from_kuid_munged(current_user_ns(), tun
->owner
)):
1162 sprintf(buf
, "-1\n");
1165 static ssize_t
tun_show_group(struct device
*dev
, struct device_attribute
*attr
,
1168 struct tun_struct
*tun
= netdev_priv(to_net_dev(dev
));
1169 return gid_valid(tun
->group
) ?
1170 sprintf(buf
, "%u\n",
1171 from_kgid_munged(current_user_ns(), tun
->group
)):
1172 sprintf(buf
, "-1\n");
1175 static DEVICE_ATTR(tun_flags
, 0444, tun_show_flags
, NULL
);
1176 static DEVICE_ATTR(owner
, 0444, tun_show_owner
, NULL
);
1177 static DEVICE_ATTR(group
, 0444, tun_show_group
, NULL
);
1179 static int tun_set_iff(struct net
*net
, struct file
*file
, struct ifreq
*ifr
)
1182 struct tun_struct
*tun
;
1183 struct net_device
*dev
;
1186 dev
= __dev_get_by_name(net
, ifr
->ifr_name
);
1188 const struct cred
*cred
= current_cred();
1190 if (ifr
->ifr_flags
& IFF_TUN_EXCL
)
1192 if ((ifr
->ifr_flags
& IFF_TUN
) && dev
->netdev_ops
== &tun_netdev_ops
)
1193 tun
= netdev_priv(dev
);
1194 else if ((ifr
->ifr_flags
& IFF_TAP
) && dev
->netdev_ops
== &tap_netdev_ops
)
1195 tun
= netdev_priv(dev
);
1199 if (((uid_valid(tun
->owner
) && !uid_eq(cred
->euid
, tun
->owner
)) ||
1200 (gid_valid(tun
->group
) && !in_egroup_p(tun
->group
))) &&
1201 !capable(CAP_NET_ADMIN
))
1203 err
= security_tun_dev_attach(tun
->socket
.sk
);
1207 err
= tun_attach(tun
, file
);
1213 unsigned long flags
= 0;
1215 if (!capable(CAP_NET_ADMIN
))
1217 err
= security_tun_dev_create();
1222 if (ifr
->ifr_flags
& IFF_TUN
) {
1224 flags
|= TUN_TUN_DEV
;
1226 } else if (ifr
->ifr_flags
& IFF_TAP
) {
1228 flags
|= TUN_TAP_DEV
;
1234 name
= ifr
->ifr_name
;
1236 dev
= alloc_netdev(sizeof(struct tun_struct
), name
,
1241 dev_net_set(dev
, net
);
1242 dev
->rtnl_link_ops
= &tun_link_ops
;
1244 tun
= netdev_priv(dev
);
1247 tun
->txflt
.count
= 0;
1248 tun
->vnet_hdr_sz
= sizeof(struct virtio_net_hdr
);
1249 set_bit(SOCK_EXTERNALLY_ALLOCATED
, &tun
->socket
.flags
);
1252 sk
= sk_alloc(&init_net
, AF_UNSPEC
, GFP_KERNEL
, &tun_proto
);
1256 sk_change_net(sk
, net
);
1257 tun
->socket
.wq
= &tun
->wq
;
1258 init_waitqueue_head(&tun
->wq
.wait
);
1259 tun
->socket
.ops
= &tun_socket_ops
;
1260 sock_init_data(&tun
->socket
, sk
);
1261 sk
->sk_write_space
= tun_sock_write_space
;
1262 sk
->sk_sndbuf
= INT_MAX
;
1263 sock_set_flag(sk
, SOCK_ZEROCOPY
);
1265 tun_sk(sk
)->tun
= tun
;
1267 security_tun_dev_post_create(sk
);
1271 dev
->hw_features
= NETIF_F_SG
| NETIF_F_FRAGLIST
|
1273 dev
->features
= dev
->hw_features
;
1275 err
= register_netdevice(tun
->dev
);
1279 if (device_create_file(&tun
->dev
->dev
, &dev_attr_tun_flags
) ||
1280 device_create_file(&tun
->dev
->dev
, &dev_attr_owner
) ||
1281 device_create_file(&tun
->dev
->dev
, &dev_attr_group
))
1282 pr_err("Failed to create tun sysfs files\n");
1284 sk
->sk_destruct
= tun_sock_destruct
;
1286 err
= tun_attach(tun
, file
);
1291 tun_debug(KERN_INFO
, tun
, "tun_set_iff\n");
1293 if (ifr
->ifr_flags
& IFF_NO_PI
)
1294 tun
->flags
|= TUN_NO_PI
;
1296 tun
->flags
&= ~TUN_NO_PI
;
1298 if (ifr
->ifr_flags
& IFF_ONE_QUEUE
)
1299 tun
->flags
|= TUN_ONE_QUEUE
;
1301 tun
->flags
&= ~TUN_ONE_QUEUE
;
1303 if (ifr
->ifr_flags
& IFF_VNET_HDR
)
1304 tun
->flags
|= TUN_VNET_HDR
;
1306 tun
->flags
&= ~TUN_VNET_HDR
;
1308 /* Make sure persistent devices do not get stuck in
1311 if (netif_running(tun
->dev
))
1312 netif_wake_queue(tun
->dev
);
1314 strcpy(ifr
->ifr_name
, tun
->dev
->name
);
1318 tun_free_netdev(dev
);
1325 static int tun_get_iff(struct net
*net
, struct tun_struct
*tun
,
1328 tun_debug(KERN_INFO
, tun
, "tun_get_iff\n");
1330 strcpy(ifr
->ifr_name
, tun
->dev
->name
);
1332 ifr
->ifr_flags
= tun_flags(tun
);
1337 /* This is like a cut-down ethtool ops, except done via tun fd so no
1338 * privs required. */
1339 static int set_offload(struct tun_struct
*tun
, unsigned long arg
)
1341 netdev_features_t features
= 0;
1343 if (arg
& TUN_F_CSUM
) {
1344 features
|= NETIF_F_HW_CSUM
;
1347 if (arg
& (TUN_F_TSO4
|TUN_F_TSO6
)) {
1348 if (arg
& TUN_F_TSO_ECN
) {
1349 features
|= NETIF_F_TSO_ECN
;
1350 arg
&= ~TUN_F_TSO_ECN
;
1352 if (arg
& TUN_F_TSO4
)
1353 features
|= NETIF_F_TSO
;
1354 if (arg
& TUN_F_TSO6
)
1355 features
|= NETIF_F_TSO6
;
1356 arg
&= ~(TUN_F_TSO4
|TUN_F_TSO6
);
1359 if (arg
& TUN_F_UFO
) {
1360 features
|= NETIF_F_UFO
;
1365 /* This gives the user a way to test for new features in future by
1366 * trying to set them. */
1370 tun
->set_features
= features
;
1371 netdev_update_features(tun
->dev
);
1376 static long __tun_chr_ioctl(struct file
*file
, unsigned int cmd
,
1377 unsigned long arg
, int ifreq_len
)
1379 struct tun_file
*tfile
= file
->private_data
;
1380 struct tun_struct
*tun
;
1381 void __user
* argp
= (void __user
*)arg
;
1382 struct sock_fprog fprog
;
1390 if (cmd
== TUNSETIFF
|| _IOC_TYPE(cmd
) == 0x89) {
1391 if (copy_from_user(&ifr
, argp
, ifreq_len
))
1394 memset(&ifr
, 0, sizeof(ifr
));
1396 if (cmd
== TUNGETFEATURES
) {
1397 /* Currently this just means: "what IFF flags are valid?".
1398 * This is needed because we never checked for invalid flags on
1400 return put_user(IFF_TUN
| IFF_TAP
| IFF_NO_PI
| IFF_ONE_QUEUE
|
1402 (unsigned int __user
*)argp
);
1407 tun
= __tun_get(tfile
);
1408 if (cmd
== TUNSETIFF
&& !tun
) {
1409 ifr
.ifr_name
[IFNAMSIZ
-1] = '\0';
1411 ret
= tun_set_iff(tfile
->net
, file
, &ifr
);
1416 if (copy_to_user(argp
, &ifr
, ifreq_len
))
1425 tun_debug(KERN_INFO
, tun
, "tun_chr_ioctl cmd %d\n", cmd
);
1430 ret
= tun_get_iff(current
->nsproxy
->net_ns
, tun
, &ifr
);
1434 if (copy_to_user(argp
, &ifr
, ifreq_len
))
1439 /* Disable/Enable checksum */
1441 /* [unimplemented] */
1442 tun_debug(KERN_INFO
, tun
, "ignored: set checksum %s\n",
1443 arg
? "disabled" : "enabled");
1447 /* Disable/Enable persist mode */
1449 tun
->flags
|= TUN_PERSIST
;
1451 tun
->flags
&= ~TUN_PERSIST
;
1453 tun_debug(KERN_INFO
, tun
, "persist %s\n",
1454 arg
? "enabled" : "disabled");
1458 /* Set owner of the device */
1459 owner
= make_kuid(current_user_ns(), arg
);
1460 if (!uid_valid(owner
)) {
1465 tun_debug(KERN_INFO
, tun
, "owner set to %d\n",
1466 from_kuid(&init_user_ns
, tun
->owner
));
1470 /* Set group of the device */
1471 group
= make_kgid(current_user_ns(), arg
);
1472 if (!gid_valid(group
)) {
1477 tun_debug(KERN_INFO
, tun
, "group set to %d\n",
1478 from_kgid(&init_user_ns
, tun
->group
));
1482 /* Only allow setting the type when the interface is down */
1483 if (tun
->dev
->flags
& IFF_UP
) {
1484 tun_debug(KERN_INFO
, tun
,
1485 "Linktype set failed because interface is up\n");
1488 tun
->dev
->type
= (int) arg
;
1489 tun_debug(KERN_INFO
, tun
, "linktype set to %d\n",
1501 ret
= set_offload(tun
, arg
);
1504 case TUNSETTXFILTER
:
1505 /* Can be set only for TAPs */
1507 if ((tun
->flags
& TUN_TYPE_MASK
) != TUN_TAP_DEV
)
1509 ret
= update_filter(&tun
->txflt
, (void __user
*)arg
);
1513 /* Get hw address */
1514 memcpy(ifr
.ifr_hwaddr
.sa_data
, tun
->dev
->dev_addr
, ETH_ALEN
);
1515 ifr
.ifr_hwaddr
.sa_family
= tun
->dev
->type
;
1516 if (copy_to_user(argp
, &ifr
, ifreq_len
))
1521 /* Set hw address */
1522 tun_debug(KERN_DEBUG
, tun
, "set hw address: %pM\n",
1523 ifr
.ifr_hwaddr
.sa_data
);
1525 ret
= dev_set_mac_address(tun
->dev
, &ifr
.ifr_hwaddr
);
1529 sndbuf
= tun
->socket
.sk
->sk_sndbuf
;
1530 if (copy_to_user(argp
, &sndbuf
, sizeof(sndbuf
)))
1535 if (copy_from_user(&sndbuf
, argp
, sizeof(sndbuf
))) {
1540 tun
->socket
.sk
->sk_sndbuf
= sndbuf
;
1543 case TUNGETVNETHDRSZ
:
1544 vnet_hdr_sz
= tun
->vnet_hdr_sz
;
1545 if (copy_to_user(argp
, &vnet_hdr_sz
, sizeof(vnet_hdr_sz
)))
1549 case TUNSETVNETHDRSZ
:
1550 if (copy_from_user(&vnet_hdr_sz
, argp
, sizeof(vnet_hdr_sz
))) {
1554 if (vnet_hdr_sz
< (int)sizeof(struct virtio_net_hdr
)) {
1559 tun
->vnet_hdr_sz
= vnet_hdr_sz
;
1562 case TUNATTACHFILTER
:
1563 /* Can be set only for TAPs */
1565 if ((tun
->flags
& TUN_TYPE_MASK
) != TUN_TAP_DEV
)
1568 if (copy_from_user(&fprog
, argp
, sizeof(fprog
)))
1571 ret
= sk_attach_filter(&fprog
, tun
->socket
.sk
);
1574 case TUNDETACHFILTER
:
1575 /* Can be set only for TAPs */
1577 if ((tun
->flags
& TUN_TYPE_MASK
) != TUN_TAP_DEV
)
1579 ret
= sk_detach_filter(tun
->socket
.sk
);
1594 static long tun_chr_ioctl(struct file
*file
,
1595 unsigned int cmd
, unsigned long arg
)
1597 return __tun_chr_ioctl(file
, cmd
, arg
, sizeof (struct ifreq
));
1600 #ifdef CONFIG_COMPAT
1601 static long tun_chr_compat_ioctl(struct file
*file
,
1602 unsigned int cmd
, unsigned long arg
)
1607 case TUNSETTXFILTER
:
1612 arg
= (unsigned long)compat_ptr(arg
);
1615 arg
= (compat_ulong_t
)arg
;
1620 * compat_ifreq is shorter than ifreq, so we must not access beyond
1621 * the end of that structure. All fields that are used in this
1622 * driver are compatible though, we don't need to convert the
1625 return __tun_chr_ioctl(file
, cmd
, arg
, sizeof(struct compat_ifreq
));
1627 #endif /* CONFIG_COMPAT */
1629 static int tun_chr_fasync(int fd
, struct file
*file
, int on
)
1631 struct tun_struct
*tun
= tun_get(file
);
1637 tun_debug(KERN_INFO
, tun
, "tun_chr_fasync %d\n", on
);
1639 if ((ret
= fasync_helper(fd
, file
, on
, &tun
->fasync
)) < 0)
1643 ret
= __f_setown(file
, task_pid(current
), PIDTYPE_PID
, 0);
1646 tun
->flags
|= TUN_FASYNC
;
1648 tun
->flags
&= ~TUN_FASYNC
;
1655 static int tun_chr_open(struct inode
*inode
, struct file
* file
)
1657 struct tun_file
*tfile
;
1659 DBG1(KERN_INFO
, "tunX: tun_chr_open\n");
1661 tfile
= kmalloc(sizeof(*tfile
), GFP_KERNEL
);
1664 atomic_set(&tfile
->count
, 0);
1666 tfile
->net
= get_net(current
->nsproxy
->net_ns
);
1667 file
->private_data
= tfile
;
1671 static int tun_chr_close(struct inode
*inode
, struct file
*file
)
1673 struct tun_file
*tfile
= file
->private_data
;
1674 struct tun_struct
*tun
;
1676 tun
= __tun_get(tfile
);
1678 struct net_device
*dev
= tun
->dev
;
1680 tun_debug(KERN_INFO
, tun
, "tun_chr_close\n");
1684 /* If desirable, unregister the netdevice. */
1685 if (!(tun
->flags
& TUN_PERSIST
)) {
1687 if (dev
->reg_state
== NETREG_REGISTERED
)
1688 unregister_netdevice(dev
);
1695 sock_put(tun
->socket
.sk
);
1697 put_net(tfile
->net
);
1703 static const struct file_operations tun_fops
= {
1704 .owner
= THIS_MODULE
,
1705 .llseek
= no_llseek
,
1706 .read
= do_sync_read
,
1707 .aio_read
= tun_chr_aio_read
,
1708 .write
= do_sync_write
,
1709 .aio_write
= tun_chr_aio_write
,
1710 .poll
= tun_chr_poll
,
1711 .unlocked_ioctl
= tun_chr_ioctl
,
1712 #ifdef CONFIG_COMPAT
1713 .compat_ioctl
= tun_chr_compat_ioctl
,
1715 .open
= tun_chr_open
,
1716 .release
= tun_chr_close
,
1717 .fasync
= tun_chr_fasync
1720 static struct miscdevice tun_miscdev
= {
1723 .nodename
= "net/tun",
1727 /* ethtool interface */
1729 static int tun_get_settings(struct net_device
*dev
, struct ethtool_cmd
*cmd
)
1732 cmd
->advertising
= 0;
1733 ethtool_cmd_speed_set(cmd
, SPEED_10
);
1734 cmd
->duplex
= DUPLEX_FULL
;
1735 cmd
->port
= PORT_TP
;
1736 cmd
->phy_address
= 0;
1737 cmd
->transceiver
= XCVR_INTERNAL
;
1738 cmd
->autoneg
= AUTONEG_DISABLE
;
1744 static void tun_get_drvinfo(struct net_device
*dev
, struct ethtool_drvinfo
*info
)
1746 struct tun_struct
*tun
= netdev_priv(dev
);
1748 strlcpy(info
->driver
, DRV_NAME
, sizeof(info
->driver
));
1749 strlcpy(info
->version
, DRV_VERSION
, sizeof(info
->version
));
1751 switch (tun
->flags
& TUN_TYPE_MASK
) {
1753 strlcpy(info
->bus_info
, "tun", sizeof(info
->bus_info
));
1756 strlcpy(info
->bus_info
, "tap", sizeof(info
->bus_info
));
1761 static u32
tun_get_msglevel(struct net_device
*dev
)
1764 struct tun_struct
*tun
= netdev_priv(dev
);
1771 static void tun_set_msglevel(struct net_device
*dev
, u32 value
)
1774 struct tun_struct
*tun
= netdev_priv(dev
);
1779 static const struct ethtool_ops tun_ethtool_ops
= {
1780 .get_settings
= tun_get_settings
,
1781 .get_drvinfo
= tun_get_drvinfo
,
1782 .get_msglevel
= tun_get_msglevel
,
1783 .set_msglevel
= tun_set_msglevel
,
1784 .get_link
= ethtool_op_get_link
,
1788 static int __init
tun_init(void)
1792 pr_info("%s, %s\n", DRV_DESCRIPTION
, DRV_VERSION
);
1793 pr_info("%s\n", DRV_COPYRIGHT
);
1795 ret
= rtnl_link_register(&tun_link_ops
);
1797 pr_err("Can't register link_ops\n");
1801 ret
= misc_register(&tun_miscdev
);
1803 pr_err("Can't register misc device %d\n", TUN_MINOR
);
1808 rtnl_link_unregister(&tun_link_ops
);
1813 static void tun_cleanup(void)
1815 misc_deregister(&tun_miscdev
);
1816 rtnl_link_unregister(&tun_link_ops
);
1819 /* Get an underlying socket object from tun file. Returns error unless file is
1820 * attached to a device. The returned object works like a packet socket, it
1821 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
1822 * holding a reference to the file for as long as the socket is in use. */
1823 struct socket
*tun_get_socket(struct file
*file
)
1825 struct tun_struct
*tun
;
1826 if (file
->f_op
!= &tun_fops
)
1827 return ERR_PTR(-EINVAL
);
1828 tun
= tun_get(file
);
1830 return ERR_PTR(-EBADFD
);
1832 return &tun
->socket
;
1834 EXPORT_SYMBOL_GPL(tun_get_socket
);
1836 module_init(tun_init
);
1837 module_exit(tun_cleanup
);
1838 MODULE_DESCRIPTION(DRV_DESCRIPTION
);
1839 MODULE_AUTHOR(DRV_COPYRIGHT
);
1840 MODULE_LICENSE("GPL");
1841 MODULE_ALIAS_MISCDEV(TUN_MINOR
);
1842 MODULE_ALIAS("devname:net/tun");