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 random_ether_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 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>"
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/smp_lock.h>
48 #include <linux/poll.h>
49 #include <linux/fcntl.h>
50 #include <linux/init.h>
51 #include <linux/skbuff.h>
52 #include <linux/netdevice.h>
53 #include <linux/etherdevice.h>
54 #include <linux/miscdevice.h>
55 #include <linux/ethtool.h>
56 #include <linux/rtnetlink.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 <net/net_namespace.h>
65 #include <net/netns/generic.h>
66 #include <net/rtnetlink.h>
68 #include <asm/system.h>
69 #include <asm/uaccess.h>
71 /* Uncomment to enable debugging */
72 /* #define TUN_DEBUG 1 */
77 #define DBG if(tun->debug)printk
78 #define DBG1 if(debug==2)printk
84 #define FLT_EXACT_COUNT 8
86 unsigned int count; /* Number of addrs. Zero means disabled */
87 u32 mask[2]; /* Mask of the hashed addrs */
88 unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
93 struct tun_struct *tun;
95 wait_queue_head_t read_wait;
99 struct tun_file *tfile;
104 struct sk_buff_head readq;
106 struct net_device *dev;
107 struct fasync_struct *fasync;
109 struct tap_filter txflt;
116 static int tun_attach(struct tun_struct *tun, struct file *file)
118 struct tun_file *tfile = file->private_data;
119 const struct cred *cred = current_cred();
124 /* Check permissions */
125 if (((tun->owner != -1 && cred->euid != tun->owner) ||
126 (tun->group != -1 && cred->egid != tun->group)) &&
127 !capable(CAP_NET_ADMIN))
130 netif_tx_lock_bh(tun->dev);
144 atomic_inc(&tfile->count);
147 netif_tx_unlock_bh(tun->dev);
151 static void __tun_detach(struct tun_struct *tun)
153 struct tun_file *tfile = tun->tfile;
155 /* Detach from net device */
156 netif_tx_lock_bh(tun->dev);
159 netif_tx_unlock_bh(tun->dev);
161 /* Drop read queue */
162 skb_queue_purge(&tun->readq);
164 /* Drop the extra count on the net device */
168 static void tun_detach(struct tun_struct *tun)
175 static struct tun_struct *__tun_get(struct tun_file *tfile)
177 struct tun_struct *tun = NULL;
179 if (atomic_inc_not_zero(&tfile->count))
185 static struct tun_struct *tun_get(struct file *file)
187 return __tun_get(file->private_data);
190 static void tun_put(struct tun_struct *tun)
192 struct tun_file *tfile = tun->tfile;
194 if (atomic_dec_and_test(&tfile->count))
195 tun_detach(tfile->tun);
199 static void addr_hash_set(u32 *mask, const u8 *addr)
201 int n = ether_crc(ETH_ALEN, addr) >> 26;
202 mask[n >> 5] |= (1 << (n & 31));
205 static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
207 int n = ether_crc(ETH_ALEN, addr) >> 26;
208 return mask[n >> 5] & (1 << (n & 31));
211 static int update_filter(struct tap_filter *filter, void __user *arg)
213 struct { u8 u[ETH_ALEN]; } *addr;
214 struct tun_filter uf;
215 int err, alen, n, nexact;
217 if (copy_from_user(&uf, arg, sizeof(uf)))
226 alen = ETH_ALEN * uf.count;
227 addr = kmalloc(alen, GFP_KERNEL);
231 if (copy_from_user(addr, arg + sizeof(uf), alen)) {
236 /* The filter is updated without holding any locks. Which is
237 * perfectly safe. We disable it first and in the worst
238 * case we'll accept a few undesired packets. */
242 /* Use first set of addresses as an exact filter */
243 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
244 memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
248 /* The rest is hashed */
249 memset(filter->mask, 0, sizeof(filter->mask));
250 for (; n < uf.count; n++)
251 addr_hash_set(filter->mask, addr[n].u);
253 /* For ALLMULTI just set the mask to all ones.
254 * This overrides the mask populated above. */
255 if ((uf.flags & TUN_FLT_ALLMULTI))
256 memset(filter->mask, ~0, sizeof(filter->mask));
258 /* Now enable the filter */
260 filter->count = nexact;
262 /* Return the number of exact filters */
270 /* Returns: 0 - drop, !=0 - accept */
271 static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
273 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
275 struct ethhdr *eh = (struct ethhdr *) skb->data;
279 for (i = 0; i < filter->count; i++)
280 if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
283 /* Inexact match (multicast only) */
284 if (is_multicast_ether_addr(eh->h_dest))
285 return addr_hash_test(filter->mask, eh->h_dest);
291 * Checks whether the packet is accepted or not.
292 * Returns: 0 - drop, !=0 - accept
294 static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
299 return run_filter(filter, skb);
302 /* Network device part of the driver */
304 static const struct ethtool_ops tun_ethtool_ops;
306 /* Net device detach from fd. */
307 static void tun_net_uninit(struct net_device *dev)
309 struct tun_struct *tun = netdev_priv(dev);
310 struct tun_file *tfile = tun->tfile;
312 /* Inform the methods they need to stop using the dev.
315 wake_up_all(&tfile->read_wait);
316 if (atomic_dec_and_test(&tfile->count))
321 /* Net device open. */
322 static int tun_net_open(struct net_device *dev)
324 netif_start_queue(dev);
328 /* Net device close. */
329 static int tun_net_close(struct net_device *dev)
331 netif_stop_queue(dev);
335 /* Net device start xmit */
336 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
338 struct tun_struct *tun = netdev_priv(dev);
340 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
342 /* Drop packet if interface is not attached */
346 /* Drop if the filter does not like it.
347 * This is a noop if the filter is disabled.
348 * Filter can be enabled only for the TAP devices. */
349 if (!check_filter(&tun->txflt, skb))
352 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
353 if (!(tun->flags & TUN_ONE_QUEUE)) {
354 /* Normal queueing mode. */
355 /* Packet scheduler handles dropping of further packets. */
356 netif_stop_queue(dev);
358 /* We won't see all dropped packets individually, so overrun
359 * error is more appropriate. */
360 dev->stats.tx_fifo_errors++;
362 /* Single queue mode.
363 * Driver handles dropping of all packets itself. */
369 skb_queue_tail(&tun->readq, skb);
370 dev->trans_start = jiffies;
372 /* Notify and wake up reader process */
373 if (tun->flags & TUN_FASYNC)
374 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
375 wake_up_interruptible(&tun->tfile->read_wait);
379 dev->stats.tx_dropped++;
384 static void tun_net_mclist(struct net_device *dev)
387 * This callback is supposed to deal with mc filter in
388 * _rx_ path and has nothing to do with the _tx_ path.
389 * In rx path we always accept everything userspace gives us.
395 #define MAX_MTU 65535
398 tun_net_change_mtu(struct net_device *dev, int new_mtu)
400 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
406 static const struct net_device_ops tun_netdev_ops = {
407 .ndo_uninit = tun_net_uninit,
408 .ndo_open = tun_net_open,
409 .ndo_stop = tun_net_close,
410 .ndo_start_xmit = tun_net_xmit,
411 .ndo_change_mtu = tun_net_change_mtu,
414 static const struct net_device_ops tap_netdev_ops = {
415 .ndo_uninit = tun_net_uninit,
416 .ndo_open = tun_net_open,
417 .ndo_stop = tun_net_close,
418 .ndo_start_xmit = tun_net_xmit,
419 .ndo_change_mtu = tun_net_change_mtu,
420 .ndo_set_multicast_list = tun_net_mclist,
421 .ndo_set_mac_address = eth_mac_addr,
422 .ndo_validate_addr = eth_validate_addr,
425 /* Initialize net device. */
426 static void tun_net_init(struct net_device *dev)
428 struct tun_struct *tun = netdev_priv(dev);
430 switch (tun->flags & TUN_TYPE_MASK) {
432 dev->netdev_ops = &tun_netdev_ops;
434 /* Point-to-Point TUN Device */
435 dev->hard_header_len = 0;
439 /* Zero header length */
440 dev->type = ARPHRD_NONE;
441 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
442 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
446 dev->netdev_ops = &tap_netdev_ops;
447 /* Ethernet TAP Device */
450 random_ether_addr(dev->dev_addr);
452 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
457 /* Character device part */
460 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
462 struct tun_file *tfile = file->private_data;
463 struct tun_struct *tun = __tun_get(tfile);
464 unsigned int mask = POLLOUT | POLLWRNORM;
469 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
471 poll_wait(file, &tfile->read_wait, wait);
473 if (!skb_queue_empty(&tun->readq))
474 mask |= POLLIN | POLLRDNORM;
476 if (tun->dev->reg_state != NETREG_REGISTERED)
483 /* prepad is the amount to reserve at front. len is length after that.
484 * linear is a hint as to how much to copy (usually headers). */
485 static struct sk_buff *tun_alloc_skb(size_t prepad, size_t len, size_t linear,
491 skb = alloc_skb(prepad + len, gfp|__GFP_NOWARN);
493 skb_reserve(skb, prepad);
498 /* Under a page? Don't bother with paged skb. */
499 if (prepad + len < PAGE_SIZE)
502 /* Start with a normal skb, and add pages. */
503 skb = alloc_skb(prepad + linear, gfp);
507 skb_reserve(skb, prepad);
508 skb_put(skb, linear);
512 for (i = 0; i < MAX_SKB_FRAGS; i++) {
513 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
515 f->page = alloc_page(gfp|__GFP_ZERO);
522 skb->data_len += PAGE_SIZE;
523 skb->len += PAGE_SIZE;
524 skb->truesize += PAGE_SIZE;
525 skb_shinfo(skb)->nr_frags++;
527 if (len < PAGE_SIZE) {
534 /* Too large, or alloc fail? */
543 /* Get packet from user space buffer */
544 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
546 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
548 size_t len = count, align = 0;
549 struct virtio_net_hdr gso = { 0 };
551 if (!(tun->flags & TUN_NO_PI)) {
552 if ((len -= sizeof(pi)) > count)
555 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
559 if (tun->flags & TUN_VNET_HDR) {
560 if ((len -= sizeof(gso)) > count)
563 if (memcpy_fromiovec((void *)&gso, iv, sizeof(gso)))
566 if (gso.hdr_len > len)
570 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
571 align = NET_IP_ALIGN;
572 if (unlikely(len < ETH_HLEN))
576 if (!(skb = tun_alloc_skb(align, len, gso.hdr_len, GFP_KERNEL))) {
577 tun->dev->stats.rx_dropped++;
581 if (skb_copy_datagram_from_iovec(skb, 0, iv, len)) {
582 tun->dev->stats.rx_dropped++;
587 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
588 if (!skb_partial_csum_set(skb, gso.csum_start,
590 tun->dev->stats.rx_frame_errors++;
594 } else if (tun->flags & TUN_NOCHECKSUM)
595 skb->ip_summed = CHECKSUM_UNNECESSARY;
597 switch (tun->flags & TUN_TYPE_MASK) {
599 if (tun->flags & TUN_NO_PI) {
600 switch (skb->data[0] & 0xf0) {
602 pi.proto = htons(ETH_P_IP);
605 pi.proto = htons(ETH_P_IPV6);
608 tun->dev->stats.rx_dropped++;
614 skb_reset_mac_header(skb);
615 skb->protocol = pi.proto;
619 skb->protocol = eth_type_trans(skb, tun->dev);
623 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
625 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
626 case VIRTIO_NET_HDR_GSO_TCPV4:
627 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
629 case VIRTIO_NET_HDR_GSO_TCPV6:
630 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
633 tun->dev->stats.rx_frame_errors++;
638 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
639 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
641 skb_shinfo(skb)->gso_size = gso.gso_size;
642 if (skb_shinfo(skb)->gso_size == 0) {
643 tun->dev->stats.rx_frame_errors++;
648 /* Header must be checked, and gso_segs computed. */
649 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
650 skb_shinfo(skb)->gso_segs = 0;
655 tun->dev->stats.rx_packets++;
656 tun->dev->stats.rx_bytes += len;
661 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
662 unsigned long count, loff_t pos)
664 struct tun_struct *tun = tun_get(iocb->ki_filp);
670 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
672 result = tun_get_user(tun, (struct iovec *) iv, iov_length(iv, count));
678 /* Put packet to the user space buffer */
679 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
681 struct iovec *iv, int len)
683 struct tun_pi pi = { 0, skb->protocol };
686 if (!(tun->flags & TUN_NO_PI)) {
687 if ((len -= sizeof(pi)) < 0)
690 if (len < skb->len) {
691 /* Packet will be striped */
692 pi.flags |= TUN_PKT_STRIP;
695 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
700 if (tun->flags & TUN_VNET_HDR) {
701 struct virtio_net_hdr gso = { 0 }; /* no info leak */
702 if ((len -= sizeof(gso)) < 0)
705 if (skb_is_gso(skb)) {
706 struct skb_shared_info *sinfo = skb_shinfo(skb);
708 /* This is a hint as to how much should be linear. */
709 gso.hdr_len = skb_headlen(skb);
710 gso.gso_size = sinfo->gso_size;
711 if (sinfo->gso_type & SKB_GSO_TCPV4)
712 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
713 else if (sinfo->gso_type & SKB_GSO_TCPV6)
714 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
717 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
718 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
720 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
722 if (skb->ip_summed == CHECKSUM_PARTIAL) {
723 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
724 gso.csum_start = skb->csum_start - skb_headroom(skb);
725 gso.csum_offset = skb->csum_offset;
726 } /* else everything is zero */
728 if (unlikely(memcpy_toiovec(iv, (void *)&gso, sizeof(gso))))
730 total += sizeof(gso);
733 len = min_t(int, skb->len, len);
735 skb_copy_datagram_iovec(skb, 0, iv, len);
738 tun->dev->stats.tx_packets++;
739 tun->dev->stats.tx_bytes += len;
744 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
745 unsigned long count, loff_t pos)
747 struct file *file = iocb->ki_filp;
748 struct tun_file *tfile = file->private_data;
749 struct tun_struct *tun = __tun_get(tfile);
750 DECLARE_WAITQUEUE(wait, current);
752 ssize_t len, ret = 0;
757 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
759 len = iov_length(iv, count);
765 add_wait_queue(&tfile->read_wait, &wait);
767 current->state = TASK_INTERRUPTIBLE;
769 /* Read frames from the queue */
770 if (!(skb=skb_dequeue(&tun->readq))) {
771 if (file->f_flags & O_NONBLOCK) {
775 if (signal_pending(current)) {
779 if (tun->dev->reg_state != NETREG_REGISTERED) {
784 /* Nothing to read, let's sleep */
788 netif_wake_queue(tun->dev);
790 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
795 current->state = TASK_RUNNING;
796 remove_wait_queue(&tfile->read_wait, &wait);
803 static void tun_setup(struct net_device *dev)
805 struct tun_struct *tun = netdev_priv(dev);
807 skb_queue_head_init(&tun->readq);
812 dev->ethtool_ops = &tun_ethtool_ops;
813 dev->destructor = free_netdev;
816 /* Trivial set of netlink ops to allow deleting tun or tap
817 * device with netlink.
819 static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
824 static struct rtnl_link_ops tun_link_ops __read_mostly = {
826 .priv_size = sizeof(struct tun_struct),
828 .validate = tun_validate,
832 static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
834 struct tun_struct *tun;
835 struct net_device *dev;
838 dev = __dev_get_by_name(net, ifr->ifr_name);
840 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
841 tun = netdev_priv(dev);
842 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
843 tun = netdev_priv(dev);
847 err = tun_attach(tun, file);
853 unsigned long flags = 0;
857 if (!capable(CAP_NET_ADMIN))
861 if (ifr->ifr_flags & IFF_TUN) {
863 flags |= TUN_TUN_DEV;
865 } else if (ifr->ifr_flags & IFF_TAP) {
867 flags |= TUN_TAP_DEV;
873 name = ifr->ifr_name;
875 dev = alloc_netdev(sizeof(struct tun_struct), name,
880 dev_net_set(dev, net);
881 dev->rtnl_link_ops = &tun_link_ops;
883 tun = netdev_priv(dev);
886 tun->txflt.count = 0;
890 if (strchr(dev->name, '%')) {
891 err = dev_alloc_name(dev, dev->name);
896 err = register_netdevice(tun->dev);
900 err = tun_attach(tun, file);
905 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
907 if (ifr->ifr_flags & IFF_NO_PI)
908 tun->flags |= TUN_NO_PI;
910 tun->flags &= ~TUN_NO_PI;
912 if (ifr->ifr_flags & IFF_ONE_QUEUE)
913 tun->flags |= TUN_ONE_QUEUE;
915 tun->flags &= ~TUN_ONE_QUEUE;
917 if (ifr->ifr_flags & IFF_VNET_HDR)
918 tun->flags |= TUN_VNET_HDR;
920 tun->flags &= ~TUN_VNET_HDR;
922 /* Make sure persistent devices do not get stuck in
925 if (netif_running(tun->dev))
926 netif_wake_queue(tun->dev);
928 strcpy(ifr->ifr_name, tun->dev->name);
937 static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr)
939 struct tun_struct *tun = tun_get(file);
944 DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
946 strcpy(ifr->ifr_name, tun->dev->name);
950 if (ifr->ifr_flags & TUN_TUN_DEV)
951 ifr->ifr_flags |= IFF_TUN;
953 ifr->ifr_flags |= IFF_TAP;
955 if (tun->flags & TUN_NO_PI)
956 ifr->ifr_flags |= IFF_NO_PI;
958 if (tun->flags & TUN_ONE_QUEUE)
959 ifr->ifr_flags |= IFF_ONE_QUEUE;
961 if (tun->flags & TUN_VNET_HDR)
962 ifr->ifr_flags |= IFF_VNET_HDR;
968 /* This is like a cut-down ethtool ops, except done via tun fd so no
970 static int set_offload(struct net_device *dev, unsigned long arg)
972 unsigned int old_features, features;
974 old_features = dev->features;
975 /* Unset features, set them as we chew on the arg. */
976 features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
977 |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6));
979 if (arg & TUN_F_CSUM) {
980 features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
983 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
984 if (arg & TUN_F_TSO_ECN) {
985 features |= NETIF_F_TSO_ECN;
986 arg &= ~TUN_F_TSO_ECN;
988 if (arg & TUN_F_TSO4)
989 features |= NETIF_F_TSO;
990 if (arg & TUN_F_TSO6)
991 features |= NETIF_F_TSO6;
992 arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
996 /* This gives the user a way to test for new features in future by
997 * trying to set them. */
1001 dev->features = features;
1002 if (old_features != dev->features)
1003 netdev_features_change(dev);
1008 static int tun_chr_ioctl(struct inode *inode, struct file *file,
1009 unsigned int cmd, unsigned long arg)
1011 struct tun_file *tfile = file->private_data;
1012 struct tun_struct *tun;
1013 void __user* argp = (void __user*)arg;
1017 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
1018 if (copy_from_user(&ifr, argp, sizeof ifr))
1021 if (cmd == TUNGETFEATURES) {
1022 /* Currently this just means: "what IFF flags are valid?".
1023 * This is needed because we never checked for invalid flags on
1025 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
1027 (unsigned int __user*)argp);
1030 tun = __tun_get(tfile);
1031 if (cmd == TUNSETIFF && !tun) {
1034 ifr.ifr_name[IFNAMSIZ-1] = '\0';
1037 err = tun_set_iff(tfile->net, file, &ifr);
1043 if (copy_to_user(argp, &ifr, sizeof(ifr)))
1052 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
1057 ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr);
1061 if (copy_to_user(argp, &ifr, sizeof(ifr)))
1066 /* Disable/Enable checksum */
1068 tun->flags |= TUN_NOCHECKSUM;
1070 tun->flags &= ~TUN_NOCHECKSUM;
1072 DBG(KERN_INFO "%s: checksum %s\n",
1073 tun->dev->name, arg ? "disabled" : "enabled");
1077 /* Disable/Enable persist mode */
1079 tun->flags |= TUN_PERSIST;
1081 tun->flags &= ~TUN_PERSIST;
1083 DBG(KERN_INFO "%s: persist %s\n",
1084 tun->dev->name, arg ? "enabled" : "disabled");
1088 /* Set owner of the device */
1089 tun->owner = (uid_t) arg;
1091 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
1095 /* Set group of the device */
1096 tun->group= (gid_t) arg;
1098 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
1102 /* Only allow setting the type when the interface is down */
1104 if (tun->dev->flags & IFF_UP) {
1105 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
1109 tun->dev->type = (int) arg;
1110 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
1123 ret = set_offload(tun->dev, arg);
1127 case TUNSETTXFILTER:
1128 /* Can be set only for TAPs */
1130 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1133 ret = update_filter(&tun->txflt, (void __user *)arg);
1139 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1140 ifr.ifr_hwaddr.sa_family = tun->dev->type;
1141 if (copy_to_user(argp, &ifr, sizeof ifr))
1146 /* Set hw address */
1147 DBG(KERN_DEBUG "%s: set hw address: %pM\n",
1148 tun->dev->name, ifr.ifr_hwaddr.sa_data);
1151 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
1163 static int tun_chr_fasync(int fd, struct file *file, int on)
1165 struct tun_struct *tun = tun_get(file);
1171 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
1174 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
1178 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
1181 tun->flags |= TUN_FASYNC;
1183 tun->flags &= ~TUN_FASYNC;
1191 static int tun_chr_open(struct inode *inode, struct file * file)
1193 struct tun_file *tfile;
1194 cycle_kernel_lock();
1195 DBG1(KERN_INFO "tunX: tun_chr_open\n");
1197 tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
1200 atomic_set(&tfile->count, 0);
1202 tfile->net = get_net(current->nsproxy->net_ns);
1203 init_waitqueue_head(&tfile->read_wait);
1204 file->private_data = tfile;
1208 static int tun_chr_close(struct inode *inode, struct file *file)
1210 struct tun_file *tfile = file->private_data;
1211 struct tun_struct *tun = __tun_get(tfile);
1215 DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
1220 /* If desireable, unregister the netdevice. */
1221 if (!(tun->flags & TUN_PERSIST))
1222 unregister_netdevice(tun->dev);
1227 put_net(tfile->net);
1233 static const struct file_operations tun_fops = {
1234 .owner = THIS_MODULE,
1235 .llseek = no_llseek,
1236 .read = do_sync_read,
1237 .aio_read = tun_chr_aio_read,
1238 .write = do_sync_write,
1239 .aio_write = tun_chr_aio_write,
1240 .poll = tun_chr_poll,
1241 .ioctl = tun_chr_ioctl,
1242 .open = tun_chr_open,
1243 .release = tun_chr_close,
1244 .fasync = tun_chr_fasync
1247 static struct miscdevice tun_miscdev = {
1253 /* ethtool interface */
1255 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1258 cmd->advertising = 0;
1259 cmd->speed = SPEED_10;
1260 cmd->duplex = DUPLEX_FULL;
1261 cmd->port = PORT_TP;
1262 cmd->phy_address = 0;
1263 cmd->transceiver = XCVR_INTERNAL;
1264 cmd->autoneg = AUTONEG_DISABLE;
1270 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1272 struct tun_struct *tun = netdev_priv(dev);
1274 strcpy(info->driver, DRV_NAME);
1275 strcpy(info->version, DRV_VERSION);
1276 strcpy(info->fw_version, "N/A");
1278 switch (tun->flags & TUN_TYPE_MASK) {
1280 strcpy(info->bus_info, "tun");
1283 strcpy(info->bus_info, "tap");
1288 static u32 tun_get_msglevel(struct net_device *dev)
1291 struct tun_struct *tun = netdev_priv(dev);
1298 static void tun_set_msglevel(struct net_device *dev, u32 value)
1301 struct tun_struct *tun = netdev_priv(dev);
1306 static u32 tun_get_link(struct net_device *dev)
1308 struct tun_struct *tun = netdev_priv(dev);
1309 return !!tun->tfile;
1312 static u32 tun_get_rx_csum(struct net_device *dev)
1314 struct tun_struct *tun = netdev_priv(dev);
1315 return (tun->flags & TUN_NOCHECKSUM) == 0;
1318 static int tun_set_rx_csum(struct net_device *dev, u32 data)
1320 struct tun_struct *tun = netdev_priv(dev);
1322 tun->flags &= ~TUN_NOCHECKSUM;
1324 tun->flags |= TUN_NOCHECKSUM;
1328 static const struct ethtool_ops tun_ethtool_ops = {
1329 .get_settings = tun_get_settings,
1330 .get_drvinfo = tun_get_drvinfo,
1331 .get_msglevel = tun_get_msglevel,
1332 .set_msglevel = tun_set_msglevel,
1333 .get_link = tun_get_link,
1334 .get_rx_csum = tun_get_rx_csum,
1335 .set_rx_csum = tun_set_rx_csum
1339 static int __init tun_init(void)
1343 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1344 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
1346 ret = rtnl_link_register(&tun_link_ops);
1348 printk(KERN_ERR "tun: Can't register link_ops\n");
1352 ret = misc_register(&tun_miscdev);
1354 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
1359 rtnl_link_unregister(&tun_link_ops);
1364 static void tun_cleanup(void)
1366 misc_deregister(&tun_miscdev);
1367 rtnl_link_unregister(&tun_link_ops);
1370 module_init(tun_init);
1371 module_exit(tun_cleanup);
1372 MODULE_DESCRIPTION(DRV_DESCRIPTION);
1373 MODULE_AUTHOR(DRV_COPYRIGHT);
1374 MODULE_LICENSE("GPL");
1375 MODULE_ALIAS_MISCDEV(TUN_MINOR);