rtl8187: Remove large delays
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / net / tun.c
blob5a6203072ce71f0694540210cf33a6ad44dc17e7
1 /*
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 $
19 * Changes:
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.
30 * Added ethtool API.
31 * Minor cleanups
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>
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 <net/net_namespace.h>
65 #include <net/netns/generic.h>
67 #include <asm/system.h>
68 #include <asm/uaccess.h>
70 /* Uncomment to enable debugging */
71 /* #define TUN_DEBUG 1 */
73 #ifdef TUN_DEBUG
74 static int debug;
76 #define DBG if(tun->debug)printk
77 #define DBG1 if(debug==2)printk
78 #else
79 #define DBG( a... )
80 #define DBG1( a... )
81 #endif
83 #define FLT_EXACT_COUNT 8
84 struct tap_filter {
85 unsigned int count; /* Number of addrs. Zero means disabled */
86 u32 mask[2]; /* Mask of the hashed addrs */
87 unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
90 struct tun_struct {
91 struct list_head list;
92 unsigned int flags;
93 int attached;
94 uid_t owner;
95 gid_t group;
97 wait_queue_head_t read_wait;
98 struct sk_buff_head readq;
100 struct net_device *dev;
101 struct fasync_struct *fasync;
103 struct tap_filter txflt;
105 #ifdef TUN_DEBUG
106 int debug;
107 #endif
110 /* TAP filterting */
111 static void addr_hash_set(u32 *mask, const u8 *addr)
113 int n = ether_crc(ETH_ALEN, addr) >> 26;
114 mask[n >> 5] |= (1 << (n & 31));
117 static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
119 int n = ether_crc(ETH_ALEN, addr) >> 26;
120 return mask[n >> 5] & (1 << (n & 31));
123 static int update_filter(struct tap_filter *filter, void __user *arg)
125 struct { u8 u[ETH_ALEN]; } *addr;
126 struct tun_filter uf;
127 int err, alen, n, nexact;
129 if (copy_from_user(&uf, arg, sizeof(uf)))
130 return -EFAULT;
132 if (!uf.count) {
133 /* Disabled */
134 filter->count = 0;
135 return 0;
138 alen = ETH_ALEN * uf.count;
139 addr = kmalloc(alen, GFP_KERNEL);
140 if (!addr)
141 return -ENOMEM;
143 if (copy_from_user(addr, arg + sizeof(uf), alen)) {
144 err = -EFAULT;
145 goto done;
148 /* The filter is updated without holding any locks. Which is
149 * perfectly safe. We disable it first and in the worst
150 * case we'll accept a few undesired packets. */
151 filter->count = 0;
152 wmb();
154 /* Use first set of addresses as an exact filter */
155 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
156 memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
158 nexact = n;
160 /* The rest is hashed */
161 memset(filter->mask, 0, sizeof(filter->mask));
162 for (; n < uf.count; n++)
163 addr_hash_set(filter->mask, addr[n].u);
165 /* For ALLMULTI just set the mask to all ones.
166 * This overrides the mask populated above. */
167 if ((uf.flags & TUN_FLT_ALLMULTI))
168 memset(filter->mask, ~0, sizeof(filter->mask));
170 /* Now enable the filter */
171 wmb();
172 filter->count = nexact;
174 /* Return the number of exact filters */
175 err = nexact;
177 done:
178 kfree(addr);
179 return err;
182 /* Returns: 0 - drop, !=0 - accept */
183 static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
185 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
186 * at this point. */
187 struct ethhdr *eh = (struct ethhdr *) skb->data;
188 int i;
190 /* Exact match */
191 for (i = 0; i < filter->count; i++)
192 if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
193 return 1;
195 /* Inexact match (multicast only) */
196 if (is_multicast_ether_addr(eh->h_dest))
197 return addr_hash_test(filter->mask, eh->h_dest);
199 return 0;
203 * Checks whether the packet is accepted or not.
204 * Returns: 0 - drop, !=0 - accept
206 static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
208 if (!filter->count)
209 return 1;
211 return run_filter(filter, skb);
214 /* Network device part of the driver */
216 static unsigned int tun_net_id;
217 struct tun_net {
218 struct list_head dev_list;
221 static const struct ethtool_ops tun_ethtool_ops;
223 /* Net device open. */
224 static int tun_net_open(struct net_device *dev)
226 netif_start_queue(dev);
227 return 0;
230 /* Net device close. */
231 static int tun_net_close(struct net_device *dev)
233 netif_stop_queue(dev);
234 return 0;
237 /* Net device start xmit */
238 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
240 struct tun_struct *tun = netdev_priv(dev);
242 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
244 /* Drop packet if interface is not attached */
245 if (!tun->attached)
246 goto drop;
248 /* Drop if the filter does not like it.
249 * This is a noop if the filter is disabled.
250 * Filter can be enabled only for the TAP devices. */
251 if (!check_filter(&tun->txflt, skb))
252 goto drop;
254 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
255 if (!(tun->flags & TUN_ONE_QUEUE)) {
256 /* Normal queueing mode. */
257 /* Packet scheduler handles dropping of further packets. */
258 netif_stop_queue(dev);
260 /* We won't see all dropped packets individually, so overrun
261 * error is more appropriate. */
262 dev->stats.tx_fifo_errors++;
263 } else {
264 /* Single queue mode.
265 * Driver handles dropping of all packets itself. */
266 goto drop;
270 /* Enqueue packet */
271 skb_queue_tail(&tun->readq, skb);
272 dev->trans_start = jiffies;
274 /* Notify and wake up reader process */
275 if (tun->flags & TUN_FASYNC)
276 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
277 wake_up_interruptible(&tun->read_wait);
278 return 0;
280 drop:
281 dev->stats.tx_dropped++;
282 kfree_skb(skb);
283 return 0;
286 static void tun_net_mclist(struct net_device *dev)
289 * This callback is supposed to deal with mc filter in
290 * _rx_ path and has nothing to do with the _tx_ path.
291 * In rx path we always accept everything userspace gives us.
293 return;
296 #define MIN_MTU 68
297 #define MAX_MTU 65535
299 static int
300 tun_net_change_mtu(struct net_device *dev, int new_mtu)
302 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
303 return -EINVAL;
304 dev->mtu = new_mtu;
305 return 0;
308 /* Initialize net device. */
309 static void tun_net_init(struct net_device *dev)
311 struct tun_struct *tun = netdev_priv(dev);
313 switch (tun->flags & TUN_TYPE_MASK) {
314 case TUN_TUN_DEV:
315 /* Point-to-Point TUN Device */
316 dev->hard_header_len = 0;
317 dev->addr_len = 0;
318 dev->mtu = 1500;
319 dev->change_mtu = tun_net_change_mtu;
321 /* Zero header length */
322 dev->type = ARPHRD_NONE;
323 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
324 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
325 break;
327 case TUN_TAP_DEV:
328 /* Ethernet TAP Device */
329 ether_setup(dev);
330 dev->change_mtu = tun_net_change_mtu;
331 dev->set_multicast_list = tun_net_mclist;
333 random_ether_addr(dev->dev_addr);
335 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
336 break;
340 /* Character device part */
342 /* Poll */
343 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
345 struct tun_struct *tun = file->private_data;
346 unsigned int mask = POLLOUT | POLLWRNORM;
348 if (!tun)
349 return -EBADFD;
351 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
353 poll_wait(file, &tun->read_wait, wait);
355 if (!skb_queue_empty(&tun->readq))
356 mask |= POLLIN | POLLRDNORM;
358 return mask;
361 /* prepad is the amount to reserve at front. len is length after that.
362 * linear is a hint as to how much to copy (usually headers). */
363 static struct sk_buff *tun_alloc_skb(size_t prepad, size_t len, size_t linear,
364 gfp_t gfp)
366 struct sk_buff *skb;
367 unsigned int i;
369 skb = alloc_skb(prepad + len, gfp|__GFP_NOWARN);
370 if (skb) {
371 skb_reserve(skb, prepad);
372 skb_put(skb, len);
373 return skb;
376 /* Under a page? Don't bother with paged skb. */
377 if (prepad + len < PAGE_SIZE)
378 return NULL;
380 /* Start with a normal skb, and add pages. */
381 skb = alloc_skb(prepad + linear, gfp);
382 if (!skb)
383 return NULL;
385 skb_reserve(skb, prepad);
386 skb_put(skb, linear);
388 len -= linear;
390 for (i = 0; i < MAX_SKB_FRAGS; i++) {
391 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
393 f->page = alloc_page(gfp|__GFP_ZERO);
394 if (!f->page)
395 break;
397 f->page_offset = 0;
398 f->size = PAGE_SIZE;
400 skb->data_len += PAGE_SIZE;
401 skb->len += PAGE_SIZE;
402 skb->truesize += PAGE_SIZE;
403 skb_shinfo(skb)->nr_frags++;
405 if (len < PAGE_SIZE) {
406 len = 0;
407 break;
409 len -= PAGE_SIZE;
412 /* Too large, or alloc fail? */
413 if (unlikely(len)) {
414 kfree_skb(skb);
415 skb = NULL;
418 return skb;
421 /* Get packet from user space buffer */
422 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
424 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
425 struct sk_buff *skb;
426 size_t len = count, align = 0;
427 struct virtio_net_hdr gso = { 0 };
429 if (!(tun->flags & TUN_NO_PI)) {
430 if ((len -= sizeof(pi)) > count)
431 return -EINVAL;
433 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
434 return -EFAULT;
437 if (tun->flags & TUN_VNET_HDR) {
438 if ((len -= sizeof(gso)) > count)
439 return -EINVAL;
441 if (memcpy_fromiovec((void *)&gso, iv, sizeof(gso)))
442 return -EFAULT;
444 if (gso.hdr_len > len)
445 return -EINVAL;
448 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
449 align = NET_IP_ALIGN;
450 if (unlikely(len < ETH_HLEN))
451 return -EINVAL;
454 if (!(skb = tun_alloc_skb(align, len, gso.hdr_len, GFP_KERNEL))) {
455 tun->dev->stats.rx_dropped++;
456 return -ENOMEM;
459 if (skb_copy_datagram_from_iovec(skb, 0, iv, len)) {
460 tun->dev->stats.rx_dropped++;
461 kfree_skb(skb);
462 return -EFAULT;
465 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
466 if (!skb_partial_csum_set(skb, gso.csum_start,
467 gso.csum_offset)) {
468 tun->dev->stats.rx_frame_errors++;
469 kfree_skb(skb);
470 return -EINVAL;
472 } else if (tun->flags & TUN_NOCHECKSUM)
473 skb->ip_summed = CHECKSUM_UNNECESSARY;
475 switch (tun->flags & TUN_TYPE_MASK) {
476 case TUN_TUN_DEV:
477 if (tun->flags & TUN_NO_PI) {
478 switch (skb->data[0] & 0xf0) {
479 case 0x40:
480 pi.proto = htons(ETH_P_IP);
481 break;
482 case 0x60:
483 pi.proto = htons(ETH_P_IPV6);
484 break;
485 default:
486 tun->dev->stats.rx_dropped++;
487 kfree_skb(skb);
488 return -EINVAL;
492 skb_reset_mac_header(skb);
493 skb->protocol = pi.proto;
494 skb->dev = tun->dev;
495 break;
496 case TUN_TAP_DEV:
497 skb->protocol = eth_type_trans(skb, tun->dev);
498 break;
501 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
502 pr_debug("GSO!\n");
503 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
504 case VIRTIO_NET_HDR_GSO_TCPV4:
505 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
506 break;
507 case VIRTIO_NET_HDR_GSO_TCPV6:
508 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
509 break;
510 default:
511 tun->dev->stats.rx_frame_errors++;
512 kfree_skb(skb);
513 return -EINVAL;
516 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
517 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
519 skb_shinfo(skb)->gso_size = gso.gso_size;
520 if (skb_shinfo(skb)->gso_size == 0) {
521 tun->dev->stats.rx_frame_errors++;
522 kfree_skb(skb);
523 return -EINVAL;
526 /* Header must be checked, and gso_segs computed. */
527 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
528 skb_shinfo(skb)->gso_segs = 0;
531 netif_rx_ni(skb);
533 tun->dev->stats.rx_packets++;
534 tun->dev->stats.rx_bytes += len;
536 return count;
539 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
540 unsigned long count, loff_t pos)
542 struct tun_struct *tun = iocb->ki_filp->private_data;
544 if (!tun)
545 return -EBADFD;
547 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
549 return tun_get_user(tun, (struct iovec *) iv, iov_length(iv, count));
552 /* Put packet to the user space buffer */
553 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
554 struct sk_buff *skb,
555 struct iovec *iv, int len)
557 struct tun_pi pi = { 0, skb->protocol };
558 ssize_t total = 0;
560 if (!(tun->flags & TUN_NO_PI)) {
561 if ((len -= sizeof(pi)) < 0)
562 return -EINVAL;
564 if (len < skb->len) {
565 /* Packet will be striped */
566 pi.flags |= TUN_PKT_STRIP;
569 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
570 return -EFAULT;
571 total += sizeof(pi);
574 if (tun->flags & TUN_VNET_HDR) {
575 struct virtio_net_hdr gso = { 0 }; /* no info leak */
576 if ((len -= sizeof(gso)) < 0)
577 return -EINVAL;
579 if (skb_is_gso(skb)) {
580 struct skb_shared_info *sinfo = skb_shinfo(skb);
582 /* This is a hint as to how much should be linear. */
583 gso.hdr_len = skb_headlen(skb);
584 gso.gso_size = sinfo->gso_size;
585 if (sinfo->gso_type & SKB_GSO_TCPV4)
586 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
587 else if (sinfo->gso_type & SKB_GSO_TCPV6)
588 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
589 else
590 BUG();
591 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
592 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
593 } else
594 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
596 if (skb->ip_summed == CHECKSUM_PARTIAL) {
597 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
598 gso.csum_start = skb->csum_start - skb_headroom(skb);
599 gso.csum_offset = skb->csum_offset;
600 } /* else everything is zero */
602 if (unlikely(memcpy_toiovec(iv, (void *)&gso, sizeof(gso))))
603 return -EFAULT;
604 total += sizeof(gso);
607 len = min_t(int, skb->len, len);
609 skb_copy_datagram_iovec(skb, 0, iv, len);
610 total += len;
612 tun->dev->stats.tx_packets++;
613 tun->dev->stats.tx_bytes += len;
615 return total;
618 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
619 unsigned long count, loff_t pos)
621 struct file *file = iocb->ki_filp;
622 struct tun_struct *tun = file->private_data;
623 DECLARE_WAITQUEUE(wait, current);
624 struct sk_buff *skb;
625 ssize_t len, ret = 0;
627 if (!tun)
628 return -EBADFD;
630 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
632 len = iov_length(iv, count);
633 if (len < 0)
634 return -EINVAL;
636 add_wait_queue(&tun->read_wait, &wait);
637 while (len) {
638 current->state = TASK_INTERRUPTIBLE;
640 /* Read frames from the queue */
641 if (!(skb=skb_dequeue(&tun->readq))) {
642 if (file->f_flags & O_NONBLOCK) {
643 ret = -EAGAIN;
644 break;
646 if (signal_pending(current)) {
647 ret = -ERESTARTSYS;
648 break;
651 /* Nothing to read, let's sleep */
652 schedule();
653 continue;
655 netif_wake_queue(tun->dev);
657 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
658 kfree_skb(skb);
659 break;
662 current->state = TASK_RUNNING;
663 remove_wait_queue(&tun->read_wait, &wait);
665 return ret;
668 static void tun_setup(struct net_device *dev)
670 struct tun_struct *tun = netdev_priv(dev);
672 skb_queue_head_init(&tun->readq);
673 init_waitqueue_head(&tun->read_wait);
675 tun->owner = -1;
676 tun->group = -1;
678 dev->open = tun_net_open;
679 dev->hard_start_xmit = tun_net_xmit;
680 dev->stop = tun_net_close;
681 dev->ethtool_ops = &tun_ethtool_ops;
682 dev->destructor = free_netdev;
683 dev->features |= NETIF_F_NETNS_LOCAL;
686 static struct tun_struct *tun_get_by_name(struct tun_net *tn, const char *name)
688 struct tun_struct *tun;
690 ASSERT_RTNL();
691 list_for_each_entry(tun, &tn->dev_list, list) {
692 if (!strncmp(tun->dev->name, name, IFNAMSIZ))
693 return tun;
696 return NULL;
699 static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
701 struct tun_net *tn;
702 struct tun_struct *tun;
703 struct net_device *dev;
704 int err;
706 tn = net_generic(net, tun_net_id);
707 tun = tun_get_by_name(tn, ifr->ifr_name);
708 if (tun) {
709 if (tun->attached)
710 return -EBUSY;
712 /* Check permissions */
713 if (((tun->owner != -1 &&
714 current->euid != tun->owner) ||
715 (tun->group != -1 &&
716 current->egid != tun->group)) &&
717 !capable(CAP_NET_ADMIN))
718 return -EPERM;
720 else if (__dev_get_by_name(net, ifr->ifr_name))
721 return -EINVAL;
722 else {
723 char *name;
724 unsigned long flags = 0;
726 err = -EINVAL;
728 if (!capable(CAP_NET_ADMIN))
729 return -EPERM;
731 /* Set dev type */
732 if (ifr->ifr_flags & IFF_TUN) {
733 /* TUN device */
734 flags |= TUN_TUN_DEV;
735 name = "tun%d";
736 } else if (ifr->ifr_flags & IFF_TAP) {
737 /* TAP device */
738 flags |= TUN_TAP_DEV;
739 name = "tap%d";
740 } else
741 goto failed;
743 if (*ifr->ifr_name)
744 name = ifr->ifr_name;
746 dev = alloc_netdev(sizeof(struct tun_struct), name,
747 tun_setup);
748 if (!dev)
749 return -ENOMEM;
751 dev_net_set(dev, net);
752 tun = netdev_priv(dev);
753 tun->dev = dev;
754 tun->flags = flags;
755 tun->txflt.count = 0;
757 tun_net_init(dev);
759 if (strchr(dev->name, '%')) {
760 err = dev_alloc_name(dev, dev->name);
761 if (err < 0)
762 goto err_free_dev;
765 err = register_netdevice(tun->dev);
766 if (err < 0)
767 goto err_free_dev;
769 list_add(&tun->list, &tn->dev_list);
772 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
774 if (ifr->ifr_flags & IFF_NO_PI)
775 tun->flags |= TUN_NO_PI;
776 else
777 tun->flags &= ~TUN_NO_PI;
779 if (ifr->ifr_flags & IFF_ONE_QUEUE)
780 tun->flags |= TUN_ONE_QUEUE;
781 else
782 tun->flags &= ~TUN_ONE_QUEUE;
784 if (ifr->ifr_flags & IFF_VNET_HDR)
785 tun->flags |= TUN_VNET_HDR;
786 else
787 tun->flags &= ~TUN_VNET_HDR;
789 file->private_data = tun;
790 tun->attached = 1;
791 get_net(dev_net(tun->dev));
793 /* Make sure persistent devices do not get stuck in
794 * xoff state.
796 if (netif_running(tun->dev))
797 netif_wake_queue(tun->dev);
799 strcpy(ifr->ifr_name, tun->dev->name);
800 return 0;
802 err_free_dev:
803 free_netdev(dev);
804 failed:
805 return err;
808 static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr)
810 struct tun_struct *tun = file->private_data;
812 if (!tun)
813 return -EBADFD;
815 DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
817 strcpy(ifr->ifr_name, tun->dev->name);
819 ifr->ifr_flags = 0;
821 if (ifr->ifr_flags & TUN_TUN_DEV)
822 ifr->ifr_flags |= IFF_TUN;
823 else
824 ifr->ifr_flags |= IFF_TAP;
826 if (tun->flags & TUN_NO_PI)
827 ifr->ifr_flags |= IFF_NO_PI;
829 if (tun->flags & TUN_ONE_QUEUE)
830 ifr->ifr_flags |= IFF_ONE_QUEUE;
832 if (tun->flags & TUN_VNET_HDR)
833 ifr->ifr_flags |= IFF_VNET_HDR;
835 return 0;
838 /* This is like a cut-down ethtool ops, except done via tun fd so no
839 * privs required. */
840 static int set_offload(struct net_device *dev, unsigned long arg)
842 unsigned int old_features, features;
844 old_features = dev->features;
845 /* Unset features, set them as we chew on the arg. */
846 features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
847 |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6));
849 if (arg & TUN_F_CSUM) {
850 features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
851 arg &= ~TUN_F_CSUM;
853 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
854 if (arg & TUN_F_TSO_ECN) {
855 features |= NETIF_F_TSO_ECN;
856 arg &= ~TUN_F_TSO_ECN;
858 if (arg & TUN_F_TSO4)
859 features |= NETIF_F_TSO;
860 if (arg & TUN_F_TSO6)
861 features |= NETIF_F_TSO6;
862 arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
866 /* This gives the user a way to test for new features in future by
867 * trying to set them. */
868 if (arg)
869 return -EINVAL;
871 dev->features = features;
872 if (old_features != dev->features)
873 netdev_features_change(dev);
875 return 0;
878 static int tun_chr_ioctl(struct inode *inode, struct file *file,
879 unsigned int cmd, unsigned long arg)
881 struct tun_struct *tun = file->private_data;
882 void __user* argp = (void __user*)arg;
883 struct ifreq ifr;
884 int ret;
886 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
887 if (copy_from_user(&ifr, argp, sizeof ifr))
888 return -EFAULT;
890 if (cmd == TUNSETIFF && !tun) {
891 int err;
893 ifr.ifr_name[IFNAMSIZ-1] = '\0';
895 rtnl_lock();
896 err = tun_set_iff(current->nsproxy->net_ns, file, &ifr);
897 rtnl_unlock();
899 if (err)
900 return err;
902 if (copy_to_user(argp, &ifr, sizeof(ifr)))
903 return -EFAULT;
904 return 0;
907 if (cmd == TUNGETFEATURES) {
908 /* Currently this just means: "what IFF flags are valid?".
909 * This is needed because we never checked for invalid flags on
910 * TUNSETIFF. */
911 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
912 IFF_VNET_HDR,
913 (unsigned int __user*)argp);
916 if (!tun)
917 return -EBADFD;
919 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
921 switch (cmd) {
922 case TUNGETIFF:
923 ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr);
924 if (ret)
925 return ret;
927 if (copy_to_user(argp, &ifr, sizeof(ifr)))
928 return -EFAULT;
929 break;
931 case TUNSETNOCSUM:
932 /* Disable/Enable checksum */
933 if (arg)
934 tun->flags |= TUN_NOCHECKSUM;
935 else
936 tun->flags &= ~TUN_NOCHECKSUM;
938 DBG(KERN_INFO "%s: checksum %s\n",
939 tun->dev->name, arg ? "disabled" : "enabled");
940 break;
942 case TUNSETPERSIST:
943 /* Disable/Enable persist mode */
944 if (arg)
945 tun->flags |= TUN_PERSIST;
946 else
947 tun->flags &= ~TUN_PERSIST;
949 DBG(KERN_INFO "%s: persist %s\n",
950 tun->dev->name, arg ? "enabled" : "disabled");
951 break;
953 case TUNSETOWNER:
954 /* Set owner of the device */
955 tun->owner = (uid_t) arg;
957 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
958 break;
960 case TUNSETGROUP:
961 /* Set group of the device */
962 tun->group= (gid_t) arg;
964 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
965 break;
967 case TUNSETLINK:
968 /* Only allow setting the type when the interface is down */
969 rtnl_lock();
970 if (tun->dev->flags & IFF_UP) {
971 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
972 tun->dev->name);
973 ret = -EBUSY;
974 } else {
975 tun->dev->type = (int) arg;
976 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
977 ret = 0;
979 rtnl_unlock();
980 return ret;
982 #ifdef TUN_DEBUG
983 case TUNSETDEBUG:
984 tun->debug = arg;
985 break;
986 #endif
987 case TUNSETOFFLOAD:
988 rtnl_lock();
989 ret = set_offload(tun->dev, arg);
990 rtnl_unlock();
991 return ret;
993 case TUNSETTXFILTER:
994 /* Can be set only for TAPs */
995 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
996 return -EINVAL;
997 rtnl_lock();
998 ret = update_filter(&tun->txflt, (void __user *)arg);
999 rtnl_unlock();
1000 return ret;
1002 case SIOCGIFHWADDR:
1003 /* Get hw addres */
1004 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1005 ifr.ifr_hwaddr.sa_family = tun->dev->type;
1006 if (copy_to_user(argp, &ifr, sizeof ifr))
1007 return -EFAULT;
1008 return 0;
1010 case SIOCSIFHWADDR:
1011 /* Set hw address */
1012 DBG(KERN_DEBUG "%s: set hw address: %pM\n",
1013 tun->dev->name, ifr.ifr_hwaddr.sa_data);
1015 rtnl_lock();
1016 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
1017 rtnl_unlock();
1018 return ret;
1020 default:
1021 return -EINVAL;
1024 return 0;
1027 static int tun_chr_fasync(int fd, struct file *file, int on)
1029 struct tun_struct *tun = file->private_data;
1030 int ret;
1032 if (!tun)
1033 return -EBADFD;
1035 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
1037 lock_kernel();
1038 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
1039 goto out;
1041 if (on) {
1042 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
1043 if (ret)
1044 goto out;
1045 tun->flags |= TUN_FASYNC;
1046 } else
1047 tun->flags &= ~TUN_FASYNC;
1048 ret = 0;
1049 out:
1050 unlock_kernel();
1051 return ret;
1054 static int tun_chr_open(struct inode *inode, struct file * file)
1056 cycle_kernel_lock();
1057 DBG1(KERN_INFO "tunX: tun_chr_open\n");
1058 file->private_data = NULL;
1059 return 0;
1062 static int tun_chr_close(struct inode *inode, struct file *file)
1064 struct tun_struct *tun = file->private_data;
1066 if (!tun)
1067 return 0;
1069 DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
1071 rtnl_lock();
1073 /* Detach from net device */
1074 file->private_data = NULL;
1075 tun->attached = 0;
1076 put_net(dev_net(tun->dev));
1078 /* Drop read queue */
1079 skb_queue_purge(&tun->readq);
1081 if (!(tun->flags & TUN_PERSIST)) {
1082 list_del(&tun->list);
1083 unregister_netdevice(tun->dev);
1086 rtnl_unlock();
1088 return 0;
1091 static const struct file_operations tun_fops = {
1092 .owner = THIS_MODULE,
1093 .llseek = no_llseek,
1094 .read = do_sync_read,
1095 .aio_read = tun_chr_aio_read,
1096 .write = do_sync_write,
1097 .aio_write = tun_chr_aio_write,
1098 .poll = tun_chr_poll,
1099 .ioctl = tun_chr_ioctl,
1100 .open = tun_chr_open,
1101 .release = tun_chr_close,
1102 .fasync = tun_chr_fasync
1105 static struct miscdevice tun_miscdev = {
1106 .minor = TUN_MINOR,
1107 .name = "tun",
1108 .fops = &tun_fops,
1111 /* ethtool interface */
1113 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1115 cmd->supported = 0;
1116 cmd->advertising = 0;
1117 cmd->speed = SPEED_10;
1118 cmd->duplex = DUPLEX_FULL;
1119 cmd->port = PORT_TP;
1120 cmd->phy_address = 0;
1121 cmd->transceiver = XCVR_INTERNAL;
1122 cmd->autoneg = AUTONEG_DISABLE;
1123 cmd->maxtxpkt = 0;
1124 cmd->maxrxpkt = 0;
1125 return 0;
1128 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1130 struct tun_struct *tun = netdev_priv(dev);
1132 strcpy(info->driver, DRV_NAME);
1133 strcpy(info->version, DRV_VERSION);
1134 strcpy(info->fw_version, "N/A");
1136 switch (tun->flags & TUN_TYPE_MASK) {
1137 case TUN_TUN_DEV:
1138 strcpy(info->bus_info, "tun");
1139 break;
1140 case TUN_TAP_DEV:
1141 strcpy(info->bus_info, "tap");
1142 break;
1146 static u32 tun_get_msglevel(struct net_device *dev)
1148 #ifdef TUN_DEBUG
1149 struct tun_struct *tun = netdev_priv(dev);
1150 return tun->debug;
1151 #else
1152 return -EOPNOTSUPP;
1153 #endif
1156 static void tun_set_msglevel(struct net_device *dev, u32 value)
1158 #ifdef TUN_DEBUG
1159 struct tun_struct *tun = netdev_priv(dev);
1160 tun->debug = value;
1161 #endif
1164 static u32 tun_get_link(struct net_device *dev)
1166 struct tun_struct *tun = netdev_priv(dev);
1167 return tun->attached;
1170 static u32 tun_get_rx_csum(struct net_device *dev)
1172 struct tun_struct *tun = netdev_priv(dev);
1173 return (tun->flags & TUN_NOCHECKSUM) == 0;
1176 static int tun_set_rx_csum(struct net_device *dev, u32 data)
1178 struct tun_struct *tun = netdev_priv(dev);
1179 if (data)
1180 tun->flags &= ~TUN_NOCHECKSUM;
1181 else
1182 tun->flags |= TUN_NOCHECKSUM;
1183 return 0;
1186 static const struct ethtool_ops tun_ethtool_ops = {
1187 .get_settings = tun_get_settings,
1188 .get_drvinfo = tun_get_drvinfo,
1189 .get_msglevel = tun_get_msglevel,
1190 .set_msglevel = tun_set_msglevel,
1191 .get_link = tun_get_link,
1192 .get_rx_csum = tun_get_rx_csum,
1193 .set_rx_csum = tun_set_rx_csum
1196 static int tun_init_net(struct net *net)
1198 struct tun_net *tn;
1200 tn = kmalloc(sizeof(*tn), GFP_KERNEL);
1201 if (tn == NULL)
1202 return -ENOMEM;
1204 INIT_LIST_HEAD(&tn->dev_list);
1206 if (net_assign_generic(net, tun_net_id, tn)) {
1207 kfree(tn);
1208 return -ENOMEM;
1211 return 0;
1214 static void tun_exit_net(struct net *net)
1216 struct tun_net *tn;
1217 struct tun_struct *tun, *nxt;
1219 tn = net_generic(net, tun_net_id);
1221 rtnl_lock();
1222 list_for_each_entry_safe(tun, nxt, &tn->dev_list, list) {
1223 DBG(KERN_INFO "%s cleaned up\n", tun->dev->name);
1224 unregister_netdevice(tun->dev);
1226 rtnl_unlock();
1228 kfree(tn);
1231 static struct pernet_operations tun_net_ops = {
1232 .init = tun_init_net,
1233 .exit = tun_exit_net,
1236 static int __init tun_init(void)
1238 int ret = 0;
1240 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1241 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
1243 ret = register_pernet_gen_device(&tun_net_id, &tun_net_ops);
1244 if (ret) {
1245 printk(KERN_ERR "tun: Can't register pernet ops\n");
1246 goto err_pernet;
1249 ret = misc_register(&tun_miscdev);
1250 if (ret) {
1251 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
1252 goto err_misc;
1254 return 0;
1256 err_misc:
1257 unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
1258 err_pernet:
1259 return ret;
1262 static void tun_cleanup(void)
1264 misc_deregister(&tun_miscdev);
1265 unregister_pernet_gen_device(tun_net_id, &tun_net_ops);
1268 module_init(tun_init);
1269 module_exit(tun_cleanup);
1270 MODULE_DESCRIPTION(DRV_DESCRIPTION);
1271 MODULE_AUTHOR(DRV_COPYRIGHT);
1272 MODULE_LICENSE("GPL");
1273 MODULE_ALIAS_MISCDEV(TUN_MINOR);