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/sched/signal.h>
48 #include <linux/major.h>
49 #include <linux/slab.h>
50 #include <linux/poll.h>
51 #include <linux/fcntl.h>
52 #include <linux/init.h>
53 #include <linux/skbuff.h>
54 #include <linux/netdevice.h>
55 #include <linux/etherdevice.h>
56 #include <linux/miscdevice.h>
57 #include <linux/ethtool.h>
58 #include <linux/rtnetlink.h>
59 #include <linux/compat.h>
61 #include <linux/if_arp.h>
62 #include <linux/if_ether.h>
63 #include <linux/if_tun.h>
64 #include <linux/if_vlan.h>
65 #include <linux/crc32.h>
66 #include <linux/nsproxy.h>
67 #include <linux/virtio_net.h>
68 #include <linux/rcupdate.h>
69 #include <net/net_namespace.h>
70 #include <net/netns/generic.h>
71 #include <net/rtnetlink.h>
73 #include <linux/seq_file.h>
74 #include <linux/uio.h>
75 #include <linux/skb_array.h>
76 #include <linux/bpf.h>
77 #include <linux/bpf_trace.h>
79 #include <linux/uaccess.h>
81 /* Uncomment to enable debugging */
82 /* #define TUN_DEBUG 1 */
87 #define tun_debug(level, tun, fmt, args...) \
90 netdev_printk(level, tun->dev, fmt, ##args); \
92 #define DBG1(level, fmt, args...) \
95 printk(level fmt, ##args); \
98 #define tun_debug(level, tun, fmt, args...) \
101 netdev_printk(level, tun->dev, fmt, ##args); \
103 #define DBG1(level, fmt, args...) \
106 printk(level fmt, ##args); \
110 #define TUN_HEADROOM 256
111 #define TUN_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD + TUN_HEADROOM)
113 /* TUN device flags */
115 /* IFF_ATTACH_QUEUE is never stored in device flags,
116 * overload it to mean fasync when stored there.
118 #define TUN_FASYNC IFF_ATTACH_QUEUE
119 /* High bits in flags field are unused. */
120 #define TUN_VNET_LE 0x80000000
121 #define TUN_VNET_BE 0x40000000
123 #define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \
125 #define GOODCOPY_LEN 128
127 #define FLT_EXACT_COUNT 8
129 unsigned int count
; /* Number of addrs. Zero means disabled */
130 u32 mask
[2]; /* Mask of the hashed addrs */
131 unsigned char addr
[FLT_EXACT_COUNT
][ETH_ALEN
];
134 /* MAX_TAP_QUEUES 256 is chosen to allow rx/tx queues to be equal
135 * to max number of VCPUs in guest. */
136 #define MAX_TAP_QUEUES 256
137 #define MAX_TAP_FLOWS 4096
139 #define TUN_FLOW_EXPIRE (3 * HZ)
141 struct tun_pcpu_stats
{
146 struct u64_stats_sync syncp
;
152 /* A tun_file connects an open character device to a tuntap netdevice. It
153 * also contains all socket related structures (except sock_fprog and tap_filter)
154 * to serve as one transmit queue for tuntap device. The sock_fprog and
155 * tap_filter were kept in tun_struct since they were used for filtering for the
156 * netdevice not for a specific queue (at least I didn't see the requirement for
160 * The tun_file and tun_struct are loosely coupled, the pointer from one to the
161 * other can only be read while rcu_read_lock or rtnl_lock is held.
165 struct socket socket
;
167 struct tun_struct __rcu
*tun
;
168 struct fasync_struct
*fasync
;
169 /* only used for fasnyc */
173 unsigned int ifindex
;
175 struct list_head next
;
176 struct tun_struct
*detached
;
177 struct skb_array tx_array
;
178 struct page_frag alloc_frag
;
181 struct tun_flow_entry
{
182 struct hlist_node hash_link
;
184 struct tun_struct
*tun
;
189 unsigned long updated
;
192 #define TUN_NUM_FLOW_ENTRIES 1024
194 /* Since the socket were moved to tun_file, to preserve the behavior of persist
195 * device, socket filter, sndbuf and vnet header size were restore when the
196 * file were attached to a persist device.
199 struct tun_file __rcu
*tfiles
[MAX_TAP_QUEUES
];
200 unsigned int numqueues
;
205 struct net_device
*dev
;
206 netdev_features_t set_features
;
207 #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
213 struct tap_filter txflt
;
214 struct sock_fprog fprog
;
215 /* protected by rtnl lock */
216 bool filter_attached
;
221 struct hlist_head flows
[TUN_NUM_FLOW_ENTRIES
];
222 struct timer_list flow_gc_timer
;
223 unsigned long ageing_time
;
224 unsigned int numdisabled
;
225 struct list_head disabled
;
229 struct tun_pcpu_stats __percpu
*pcpu_stats
;
230 struct bpf_prog __rcu
*xdp_prog
;
233 #ifdef CONFIG_TUN_VNET_CROSS_LE
234 static inline bool tun_legacy_is_little_endian(struct tun_struct
*tun
)
236 return tun
->flags
& TUN_VNET_BE
? false :
237 virtio_legacy_is_little_endian();
240 static long tun_get_vnet_be(struct tun_struct
*tun
, int __user
*argp
)
242 int be
= !!(tun
->flags
& TUN_VNET_BE
);
244 if (put_user(be
, argp
))
250 static long tun_set_vnet_be(struct tun_struct
*tun
, int __user
*argp
)
254 if (get_user(be
, argp
))
258 tun
->flags
|= TUN_VNET_BE
;
260 tun
->flags
&= ~TUN_VNET_BE
;
265 static inline bool tun_legacy_is_little_endian(struct tun_struct
*tun
)
267 return virtio_legacy_is_little_endian();
270 static long tun_get_vnet_be(struct tun_struct
*tun
, int __user
*argp
)
275 static long tun_set_vnet_be(struct tun_struct
*tun
, int __user
*argp
)
279 #endif /* CONFIG_TUN_VNET_CROSS_LE */
281 static inline bool tun_is_little_endian(struct tun_struct
*tun
)
283 return tun
->flags
& TUN_VNET_LE
||
284 tun_legacy_is_little_endian(tun
);
287 static inline u16
tun16_to_cpu(struct tun_struct
*tun
, __virtio16 val
)
289 return __virtio16_to_cpu(tun_is_little_endian(tun
), val
);
292 static inline __virtio16
cpu_to_tun16(struct tun_struct
*tun
, u16 val
)
294 return __cpu_to_virtio16(tun_is_little_endian(tun
), val
);
297 static inline u32
tun_hashfn(u32 rxhash
)
299 return rxhash
& 0x3ff;
302 static struct tun_flow_entry
*tun_flow_find(struct hlist_head
*head
, u32 rxhash
)
304 struct tun_flow_entry
*e
;
306 hlist_for_each_entry_rcu(e
, head
, hash_link
) {
307 if (e
->rxhash
== rxhash
)
313 static struct tun_flow_entry
*tun_flow_create(struct tun_struct
*tun
,
314 struct hlist_head
*head
,
315 u32 rxhash
, u16 queue_index
)
317 struct tun_flow_entry
*e
= kmalloc(sizeof(*e
), GFP_ATOMIC
);
320 tun_debug(KERN_INFO
, tun
, "create flow: hash %u index %u\n",
321 rxhash
, queue_index
);
322 e
->updated
= jiffies
;
325 e
->queue_index
= queue_index
;
327 hlist_add_head_rcu(&e
->hash_link
, head
);
333 static void tun_flow_delete(struct tun_struct
*tun
, struct tun_flow_entry
*e
)
335 tun_debug(KERN_INFO
, tun
, "delete flow: hash %u index %u\n",
336 e
->rxhash
, e
->queue_index
);
337 hlist_del_rcu(&e
->hash_link
);
342 static void tun_flow_flush(struct tun_struct
*tun
)
346 spin_lock_bh(&tun
->lock
);
347 for (i
= 0; i
< TUN_NUM_FLOW_ENTRIES
; i
++) {
348 struct tun_flow_entry
*e
;
349 struct hlist_node
*n
;
351 hlist_for_each_entry_safe(e
, n
, &tun
->flows
[i
], hash_link
)
352 tun_flow_delete(tun
, e
);
354 spin_unlock_bh(&tun
->lock
);
357 static void tun_flow_delete_by_queue(struct tun_struct
*tun
, u16 queue_index
)
361 spin_lock_bh(&tun
->lock
);
362 for (i
= 0; i
< TUN_NUM_FLOW_ENTRIES
; i
++) {
363 struct tun_flow_entry
*e
;
364 struct hlist_node
*n
;
366 hlist_for_each_entry_safe(e
, n
, &tun
->flows
[i
], hash_link
) {
367 if (e
->queue_index
== queue_index
)
368 tun_flow_delete(tun
, e
);
371 spin_unlock_bh(&tun
->lock
);
374 static void tun_flow_cleanup(unsigned long data
)
376 struct tun_struct
*tun
= (struct tun_struct
*)data
;
377 unsigned long delay
= tun
->ageing_time
;
378 unsigned long next_timer
= jiffies
+ delay
;
379 unsigned long count
= 0;
382 tun_debug(KERN_INFO
, tun
, "tun_flow_cleanup\n");
384 spin_lock_bh(&tun
->lock
);
385 for (i
= 0; i
< TUN_NUM_FLOW_ENTRIES
; i
++) {
386 struct tun_flow_entry
*e
;
387 struct hlist_node
*n
;
389 hlist_for_each_entry_safe(e
, n
, &tun
->flows
[i
], hash_link
) {
390 unsigned long this_timer
;
392 this_timer
= e
->updated
+ delay
;
393 if (time_before_eq(this_timer
, jiffies
))
394 tun_flow_delete(tun
, e
);
395 else if (time_before(this_timer
, next_timer
))
396 next_timer
= this_timer
;
401 mod_timer(&tun
->flow_gc_timer
, round_jiffies_up(next_timer
));
402 spin_unlock_bh(&tun
->lock
);
405 static void tun_flow_update(struct tun_struct
*tun
, u32 rxhash
,
406 struct tun_file
*tfile
)
408 struct hlist_head
*head
;
409 struct tun_flow_entry
*e
;
410 unsigned long delay
= tun
->ageing_time
;
411 u16 queue_index
= tfile
->queue_index
;
416 head
= &tun
->flows
[tun_hashfn(rxhash
)];
420 /* We may get a very small possibility of OOO during switching, not
421 * worth to optimize.*/
422 if (tun
->numqueues
== 1 || tfile
->detached
)
425 e
= tun_flow_find(head
, rxhash
);
427 /* TODO: keep queueing to old queue until it's empty? */
428 e
->queue_index
= queue_index
;
429 e
->updated
= jiffies
;
430 sock_rps_record_flow_hash(e
->rps_rxhash
);
432 spin_lock_bh(&tun
->lock
);
433 if (!tun_flow_find(head
, rxhash
) &&
434 tun
->flow_count
< MAX_TAP_FLOWS
)
435 tun_flow_create(tun
, head
, rxhash
, queue_index
);
437 if (!timer_pending(&tun
->flow_gc_timer
))
438 mod_timer(&tun
->flow_gc_timer
,
439 round_jiffies_up(jiffies
+ delay
));
440 spin_unlock_bh(&tun
->lock
);
448 * Save the hash received in the stack receive path and update the
449 * flow_hash table accordingly.
451 static inline void tun_flow_save_rps_rxhash(struct tun_flow_entry
*e
, u32 hash
)
453 if (unlikely(e
->rps_rxhash
!= hash
))
454 e
->rps_rxhash
= hash
;
457 /* We try to identify a flow through its rxhash first. The reason that
458 * we do not check rxq no. is because some cards(e.g 82599), chooses
459 * the rxq based on the txq where the last packet of the flow comes. As
460 * the userspace application move between processors, we may get a
461 * different rxq no. here. If we could not get rxhash, then we would
462 * hope the rxq no. may help here.
464 static u16
tun_select_queue(struct net_device
*dev
, struct sk_buff
*skb
,
465 void *accel_priv
, select_queue_fallback_t fallback
)
467 struct tun_struct
*tun
= netdev_priv(dev
);
468 struct tun_flow_entry
*e
;
473 numqueues
= ACCESS_ONCE(tun
->numqueues
);
475 txq
= __skb_get_hash_symmetric(skb
);
477 e
= tun_flow_find(&tun
->flows
[tun_hashfn(txq
)], txq
);
479 tun_flow_save_rps_rxhash(e
, txq
);
480 txq
= e
->queue_index
;
482 /* use multiply and shift instead of expensive divide */
483 txq
= ((u64
)txq
* numqueues
) >> 32;
484 } else if (likely(skb_rx_queue_recorded(skb
))) {
485 txq
= skb_get_rx_queue(skb
);
486 while (unlikely(txq
>= numqueues
))
494 static inline bool tun_not_capable(struct tun_struct
*tun
)
496 const struct cred
*cred
= current_cred();
497 struct net
*net
= dev_net(tun
->dev
);
499 return ((uid_valid(tun
->owner
) && !uid_eq(cred
->euid
, tun
->owner
)) ||
500 (gid_valid(tun
->group
) && !in_egroup_p(tun
->group
))) &&
501 !ns_capable(net
->user_ns
, CAP_NET_ADMIN
);
504 static void tun_set_real_num_queues(struct tun_struct
*tun
)
506 netif_set_real_num_tx_queues(tun
->dev
, tun
->numqueues
);
507 netif_set_real_num_rx_queues(tun
->dev
, tun
->numqueues
);
510 static void tun_disable_queue(struct tun_struct
*tun
, struct tun_file
*tfile
)
512 tfile
->detached
= tun
;
513 list_add_tail(&tfile
->next
, &tun
->disabled
);
517 static struct tun_struct
*tun_enable_queue(struct tun_file
*tfile
)
519 struct tun_struct
*tun
= tfile
->detached
;
521 tfile
->detached
= NULL
;
522 list_del_init(&tfile
->next
);
527 static void tun_queue_purge(struct tun_file
*tfile
)
531 while ((skb
= skb_array_consume(&tfile
->tx_array
)) != NULL
)
534 skb_queue_purge(&tfile
->sk
.sk_write_queue
);
535 skb_queue_purge(&tfile
->sk
.sk_error_queue
);
538 static void __tun_detach(struct tun_file
*tfile
, bool clean
)
540 struct tun_file
*ntfile
;
541 struct tun_struct
*tun
;
543 tun
= rtnl_dereference(tfile
->tun
);
545 if (tun
&& !tfile
->detached
) {
546 u16 index
= tfile
->queue_index
;
547 BUG_ON(index
>= tun
->numqueues
);
549 rcu_assign_pointer(tun
->tfiles
[index
],
550 tun
->tfiles
[tun
->numqueues
- 1]);
551 ntfile
= rtnl_dereference(tun
->tfiles
[index
]);
552 ntfile
->queue_index
= index
;
556 RCU_INIT_POINTER(tfile
->tun
, NULL
);
557 sock_put(&tfile
->sk
);
559 tun_disable_queue(tun
, tfile
);
562 tun_flow_delete_by_queue(tun
, tun
->numqueues
+ 1);
563 /* Drop read queue */
564 tun_queue_purge(tfile
);
565 tun_set_real_num_queues(tun
);
566 } else if (tfile
->detached
&& clean
) {
567 tun
= tun_enable_queue(tfile
);
568 sock_put(&tfile
->sk
);
572 if (tun
&& tun
->numqueues
== 0 && tun
->numdisabled
== 0) {
573 netif_carrier_off(tun
->dev
);
575 if (!(tun
->flags
& IFF_PERSIST
) &&
576 tun
->dev
->reg_state
== NETREG_REGISTERED
)
577 unregister_netdevice(tun
->dev
);
580 skb_array_cleanup(&tfile
->tx_array
);
581 if (tfile
->alloc_frag
.page
)
582 put_page(tfile
->alloc_frag
.page
);
583 sock_put(&tfile
->sk
);
587 static void tun_detach(struct tun_file
*tfile
, bool clean
)
590 __tun_detach(tfile
, clean
);
594 static void tun_detach_all(struct net_device
*dev
)
596 struct tun_struct
*tun
= netdev_priv(dev
);
597 struct bpf_prog
*xdp_prog
= rtnl_dereference(tun
->xdp_prog
);
598 struct tun_file
*tfile
, *tmp
;
599 int i
, n
= tun
->numqueues
;
601 for (i
= 0; i
< n
; i
++) {
602 tfile
= rtnl_dereference(tun
->tfiles
[i
]);
604 tfile
->socket
.sk
->sk_shutdown
= RCV_SHUTDOWN
;
605 tfile
->socket
.sk
->sk_data_ready(tfile
->socket
.sk
);
606 RCU_INIT_POINTER(tfile
->tun
, NULL
);
609 list_for_each_entry(tfile
, &tun
->disabled
, next
) {
610 tfile
->socket
.sk
->sk_shutdown
= RCV_SHUTDOWN
;
611 tfile
->socket
.sk
->sk_data_ready(tfile
->socket
.sk
);
612 RCU_INIT_POINTER(tfile
->tun
, NULL
);
614 BUG_ON(tun
->numqueues
!= 0);
617 for (i
= 0; i
< n
; i
++) {
618 tfile
= rtnl_dereference(tun
->tfiles
[i
]);
619 /* Drop read queue */
620 tun_queue_purge(tfile
);
621 sock_put(&tfile
->sk
);
623 list_for_each_entry_safe(tfile
, tmp
, &tun
->disabled
, next
) {
624 tun_enable_queue(tfile
);
625 tun_queue_purge(tfile
);
626 sock_put(&tfile
->sk
);
628 BUG_ON(tun
->numdisabled
!= 0);
631 bpf_prog_put(xdp_prog
);
633 if (tun
->flags
& IFF_PERSIST
)
634 module_put(THIS_MODULE
);
637 static int tun_attach(struct tun_struct
*tun
, struct file
*file
, bool skip_filter
)
639 struct tun_file
*tfile
= file
->private_data
;
640 struct net_device
*dev
= tun
->dev
;
643 err
= security_tun_dev_attach(tfile
->socket
.sk
, tun
->security
);
648 if (rtnl_dereference(tfile
->tun
) && !tfile
->detached
)
652 if (!(tun
->flags
& IFF_MULTI_QUEUE
) && tun
->numqueues
== 1)
656 if (!tfile
->detached
&&
657 tun
->numqueues
+ tun
->numdisabled
== MAX_TAP_QUEUES
)
662 /* Re-attach the filter to persist device */
663 if (!skip_filter
&& (tun
->filter_attached
== true)) {
664 lock_sock(tfile
->socket
.sk
);
665 err
= sk_attach_filter(&tun
->fprog
, tfile
->socket
.sk
);
666 release_sock(tfile
->socket
.sk
);
671 if (!tfile
->detached
&&
672 skb_array_init(&tfile
->tx_array
, dev
->tx_queue_len
, GFP_KERNEL
)) {
677 tfile
->queue_index
= tun
->numqueues
;
678 tfile
->socket
.sk
->sk_shutdown
&= ~RCV_SHUTDOWN
;
679 rcu_assign_pointer(tfile
->tun
, tun
);
680 rcu_assign_pointer(tun
->tfiles
[tun
->numqueues
], tfile
);
684 tun_enable_queue(tfile
);
686 sock_hold(&tfile
->sk
);
688 tun_set_real_num_queues(tun
);
690 /* device is allowed to go away first, so no need to hold extra
698 static struct tun_struct
*__tun_get(struct tun_file
*tfile
)
700 struct tun_struct
*tun
;
703 tun
= rcu_dereference(tfile
->tun
);
711 static struct tun_struct
*tun_get(struct file
*file
)
713 return __tun_get(file
->private_data
);
716 static void tun_put(struct tun_struct
*tun
)
722 static void addr_hash_set(u32
*mask
, const u8
*addr
)
724 int n
= ether_crc(ETH_ALEN
, addr
) >> 26;
725 mask
[n
>> 5] |= (1 << (n
& 31));
728 static unsigned int addr_hash_test(const u32
*mask
, const u8
*addr
)
730 int n
= ether_crc(ETH_ALEN
, addr
) >> 26;
731 return mask
[n
>> 5] & (1 << (n
& 31));
734 static int update_filter(struct tap_filter
*filter
, void __user
*arg
)
736 struct { u8 u
[ETH_ALEN
]; } *addr
;
737 struct tun_filter uf
;
738 int err
, alen
, n
, nexact
;
740 if (copy_from_user(&uf
, arg
, sizeof(uf
)))
749 alen
= ETH_ALEN
* uf
.count
;
750 addr
= memdup_user(arg
+ sizeof(uf
), alen
);
752 return PTR_ERR(addr
);
754 /* The filter is updated without holding any locks. Which is
755 * perfectly safe. We disable it first and in the worst
756 * case we'll accept a few undesired packets. */
760 /* Use first set of addresses as an exact filter */
761 for (n
= 0; n
< uf
.count
&& n
< FLT_EXACT_COUNT
; n
++)
762 memcpy(filter
->addr
[n
], addr
[n
].u
, ETH_ALEN
);
766 /* Remaining multicast addresses are hashed,
767 * unicast will leave the filter disabled. */
768 memset(filter
->mask
, 0, sizeof(filter
->mask
));
769 for (; n
< uf
.count
; n
++) {
770 if (!is_multicast_ether_addr(addr
[n
].u
)) {
771 err
= 0; /* no filter */
774 addr_hash_set(filter
->mask
, addr
[n
].u
);
777 /* For ALLMULTI just set the mask to all ones.
778 * This overrides the mask populated above. */
779 if ((uf
.flags
& TUN_FLT_ALLMULTI
))
780 memset(filter
->mask
, ~0, sizeof(filter
->mask
));
782 /* Now enable the filter */
784 filter
->count
= nexact
;
786 /* Return the number of exact filters */
793 /* Returns: 0 - drop, !=0 - accept */
794 static int run_filter(struct tap_filter
*filter
, const struct sk_buff
*skb
)
796 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
798 struct ethhdr
*eh
= (struct ethhdr
*) skb
->data
;
802 for (i
= 0; i
< filter
->count
; i
++)
803 if (ether_addr_equal(eh
->h_dest
, filter
->addr
[i
]))
806 /* Inexact match (multicast only) */
807 if (is_multicast_ether_addr(eh
->h_dest
))
808 return addr_hash_test(filter
->mask
, eh
->h_dest
);
814 * Checks whether the packet is accepted or not.
815 * Returns: 0 - drop, !=0 - accept
817 static int check_filter(struct tap_filter
*filter
, const struct sk_buff
*skb
)
822 return run_filter(filter
, skb
);
825 /* Network device part of the driver */
827 static const struct ethtool_ops tun_ethtool_ops
;
829 /* Net device detach from fd. */
830 static void tun_net_uninit(struct net_device
*dev
)
835 /* Net device open. */
836 static int tun_net_open(struct net_device
*dev
)
838 struct tun_struct
*tun
= netdev_priv(dev
);
841 netif_tx_start_all_queues(dev
);
843 for (i
= 0; i
< tun
->numqueues
; i
++) {
844 struct tun_file
*tfile
;
846 tfile
= rtnl_dereference(tun
->tfiles
[i
]);
847 tfile
->socket
.sk
->sk_write_space(tfile
->socket
.sk
);
853 /* Net device close. */
854 static int tun_net_close(struct net_device
*dev
)
856 netif_tx_stop_all_queues(dev
);
860 /* Net device start xmit */
861 static netdev_tx_t
tun_net_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
863 struct tun_struct
*tun
= netdev_priv(dev
);
864 int txq
= skb
->queue_mapping
;
865 struct tun_file
*tfile
;
869 tfile
= rcu_dereference(tun
->tfiles
[txq
]);
870 numqueues
= ACCESS_ONCE(tun
->numqueues
);
872 /* Drop packet if interface is not attached */
873 if (txq
>= numqueues
)
877 if (numqueues
== 1 && static_key_false(&rps_needed
)) {
878 /* Select queue was not called for the skbuff, so we extract the
879 * RPS hash and save it into the flow_table here.
883 rxhash
= __skb_get_hash_symmetric(skb
);
885 struct tun_flow_entry
*e
;
886 e
= tun_flow_find(&tun
->flows
[tun_hashfn(rxhash
)],
889 tun_flow_save_rps_rxhash(e
, rxhash
);
894 tun_debug(KERN_INFO
, tun
, "tun_net_xmit %d\n", skb
->len
);
898 /* Drop if the filter does not like it.
899 * This is a noop if the filter is disabled.
900 * Filter can be enabled only for the TAP devices. */
901 if (!check_filter(&tun
->txflt
, skb
))
904 if (tfile
->socket
.sk
->sk_filter
&&
905 sk_filter(tfile
->socket
.sk
, skb
))
908 if (unlikely(skb_orphan_frags_rx(skb
, GFP_ATOMIC
)))
911 skb_tx_timestamp(skb
);
913 /* Orphan the skb - required as we might hang on to it
914 * for indefinite time.
920 if (skb_array_produce(&tfile
->tx_array
, skb
))
923 /* Notify and wake up reader process */
924 if (tfile
->flags
& TUN_FASYNC
)
925 kill_fasync(&tfile
->fasync
, SIGIO
, POLL_IN
);
926 tfile
->socket
.sk
->sk_data_ready(tfile
->socket
.sk
);
932 this_cpu_inc(tun
->pcpu_stats
->tx_dropped
);
936 return NET_XMIT_DROP
;
939 static void tun_net_mclist(struct net_device
*dev
)
942 * This callback is supposed to deal with mc filter in
943 * _rx_ path and has nothing to do with the _tx_ path.
944 * In rx path we always accept everything userspace gives us.
948 static netdev_features_t
tun_net_fix_features(struct net_device
*dev
,
949 netdev_features_t features
)
951 struct tun_struct
*tun
= netdev_priv(dev
);
953 return (features
& tun
->set_features
) | (features
& ~TUN_USER_FEATURES
);
955 #ifdef CONFIG_NET_POLL_CONTROLLER
956 static void tun_poll_controller(struct net_device
*dev
)
959 * Tun only receives frames when:
960 * 1) the char device endpoint gets data from user space
961 * 2) the tun socket gets a sendmsg call from user space
962 * Since both of those are synchronous operations, we are guaranteed
963 * never to have pending data when we poll for it
964 * so there is nothing to do here but return.
965 * We need this though so netpoll recognizes us as an interface that
966 * supports polling, which enables bridge devices in virt setups to
967 * still use netconsole
973 static void tun_set_headroom(struct net_device
*dev
, int new_hr
)
975 struct tun_struct
*tun
= netdev_priv(dev
);
977 if (new_hr
< NET_SKB_PAD
)
978 new_hr
= NET_SKB_PAD
;
984 tun_net_get_stats64(struct net_device
*dev
, struct rtnl_link_stats64
*stats
)
986 u32 rx_dropped
= 0, tx_dropped
= 0, rx_frame_errors
= 0;
987 struct tun_struct
*tun
= netdev_priv(dev
);
988 struct tun_pcpu_stats
*p
;
991 for_each_possible_cpu(i
) {
992 u64 rxpackets
, rxbytes
, txpackets
, txbytes
;
995 p
= per_cpu_ptr(tun
->pcpu_stats
, i
);
997 start
= u64_stats_fetch_begin(&p
->syncp
);
998 rxpackets
= p
->rx_packets
;
999 rxbytes
= p
->rx_bytes
;
1000 txpackets
= p
->tx_packets
;
1001 txbytes
= p
->tx_bytes
;
1002 } while (u64_stats_fetch_retry(&p
->syncp
, start
));
1004 stats
->rx_packets
+= rxpackets
;
1005 stats
->rx_bytes
+= rxbytes
;
1006 stats
->tx_packets
+= txpackets
;
1007 stats
->tx_bytes
+= txbytes
;
1010 rx_dropped
+= p
->rx_dropped
;
1011 rx_frame_errors
+= p
->rx_frame_errors
;
1012 tx_dropped
+= p
->tx_dropped
;
1014 stats
->rx_dropped
= rx_dropped
;
1015 stats
->rx_frame_errors
= rx_frame_errors
;
1016 stats
->tx_dropped
= tx_dropped
;
1019 static int tun_xdp_set(struct net_device
*dev
, struct bpf_prog
*prog
,
1020 struct netlink_ext_ack
*extack
)
1022 struct tun_struct
*tun
= netdev_priv(dev
);
1023 struct bpf_prog
*old_prog
;
1025 old_prog
= rtnl_dereference(tun
->xdp_prog
);
1026 rcu_assign_pointer(tun
->xdp_prog
, prog
);
1028 bpf_prog_put(old_prog
);
1033 static u32
tun_xdp_query(struct net_device
*dev
)
1035 struct tun_struct
*tun
= netdev_priv(dev
);
1036 const struct bpf_prog
*xdp_prog
;
1038 xdp_prog
= rtnl_dereference(tun
->xdp_prog
);
1040 return xdp_prog
->aux
->id
;
1045 static int tun_xdp(struct net_device
*dev
, struct netdev_xdp
*xdp
)
1047 switch (xdp
->command
) {
1048 case XDP_SETUP_PROG
:
1049 return tun_xdp_set(dev
, xdp
->prog
, xdp
->extack
);
1050 case XDP_QUERY_PROG
:
1051 xdp
->prog_id
= tun_xdp_query(dev
);
1052 xdp
->prog_attached
= !!xdp
->prog_id
;
1059 static const struct net_device_ops tun_netdev_ops
= {
1060 .ndo_uninit
= tun_net_uninit
,
1061 .ndo_open
= tun_net_open
,
1062 .ndo_stop
= tun_net_close
,
1063 .ndo_start_xmit
= tun_net_xmit
,
1064 .ndo_fix_features
= tun_net_fix_features
,
1065 .ndo_select_queue
= tun_select_queue
,
1066 #ifdef CONFIG_NET_POLL_CONTROLLER
1067 .ndo_poll_controller
= tun_poll_controller
,
1069 .ndo_set_rx_headroom
= tun_set_headroom
,
1070 .ndo_get_stats64
= tun_net_get_stats64
,
1073 static const struct net_device_ops tap_netdev_ops
= {
1074 .ndo_uninit
= tun_net_uninit
,
1075 .ndo_open
= tun_net_open
,
1076 .ndo_stop
= tun_net_close
,
1077 .ndo_start_xmit
= tun_net_xmit
,
1078 .ndo_fix_features
= tun_net_fix_features
,
1079 .ndo_set_rx_mode
= tun_net_mclist
,
1080 .ndo_set_mac_address
= eth_mac_addr
,
1081 .ndo_validate_addr
= eth_validate_addr
,
1082 .ndo_select_queue
= tun_select_queue
,
1083 #ifdef CONFIG_NET_POLL_CONTROLLER
1084 .ndo_poll_controller
= tun_poll_controller
,
1086 .ndo_features_check
= passthru_features_check
,
1087 .ndo_set_rx_headroom
= tun_set_headroom
,
1088 .ndo_get_stats64
= tun_net_get_stats64
,
1092 static void tun_flow_init(struct tun_struct
*tun
)
1096 for (i
= 0; i
< TUN_NUM_FLOW_ENTRIES
; i
++)
1097 INIT_HLIST_HEAD(&tun
->flows
[i
]);
1099 tun
->ageing_time
= TUN_FLOW_EXPIRE
;
1100 setup_timer(&tun
->flow_gc_timer
, tun_flow_cleanup
, (unsigned long)tun
);
1101 mod_timer(&tun
->flow_gc_timer
,
1102 round_jiffies_up(jiffies
+ tun
->ageing_time
));
1105 static void tun_flow_uninit(struct tun_struct
*tun
)
1107 del_timer_sync(&tun
->flow_gc_timer
);
1108 tun_flow_flush(tun
);
1112 #define MAX_MTU 65535
1114 /* Initialize net device. */
1115 static void tun_net_init(struct net_device
*dev
)
1117 struct tun_struct
*tun
= netdev_priv(dev
);
1119 switch (tun
->flags
& TUN_TYPE_MASK
) {
1121 dev
->netdev_ops
= &tun_netdev_ops
;
1123 /* Point-to-Point TUN Device */
1124 dev
->hard_header_len
= 0;
1128 /* Zero header length */
1129 dev
->type
= ARPHRD_NONE
;
1130 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
1134 dev
->netdev_ops
= &tap_netdev_ops
;
1135 /* Ethernet TAP Device */
1137 dev
->priv_flags
&= ~IFF_TX_SKB_SHARING
;
1138 dev
->priv_flags
|= IFF_LIVE_ADDR_CHANGE
;
1140 eth_hw_addr_random(dev
);
1145 dev
->min_mtu
= MIN_MTU
;
1146 dev
->max_mtu
= MAX_MTU
- dev
->hard_header_len
;
1149 /* Character device part */
1152 static unsigned int tun_chr_poll(struct file
*file
, poll_table
*wait
)
1154 struct tun_file
*tfile
= file
->private_data
;
1155 struct tun_struct
*tun
= __tun_get(tfile
);
1157 unsigned int mask
= 0;
1162 sk
= tfile
->socket
.sk
;
1164 tun_debug(KERN_INFO
, tun
, "tun_chr_poll\n");
1166 poll_wait(file
, sk_sleep(sk
), wait
);
1168 if (!skb_array_empty(&tfile
->tx_array
))
1169 mask
|= POLLIN
| POLLRDNORM
;
1171 if (tun
->dev
->flags
& IFF_UP
&&
1172 (sock_writeable(sk
) ||
1173 (!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE
, &sk
->sk_socket
->flags
) &&
1174 sock_writeable(sk
))))
1175 mask
|= POLLOUT
| POLLWRNORM
;
1177 if (tun
->dev
->reg_state
!= NETREG_REGISTERED
)
1184 /* prepad is the amount to reserve at front. len is length after that.
1185 * linear is a hint as to how much to copy (usually headers). */
1186 static struct sk_buff
*tun_alloc_skb(struct tun_file
*tfile
,
1187 size_t prepad
, size_t len
,
1188 size_t linear
, int noblock
)
1190 struct sock
*sk
= tfile
->socket
.sk
;
1191 struct sk_buff
*skb
;
1194 /* Under a page? Don't bother with paged skb. */
1195 if (prepad
+ len
< PAGE_SIZE
|| !linear
)
1198 skb
= sock_alloc_send_pskb(sk
, prepad
+ linear
, len
- linear
, noblock
,
1201 return ERR_PTR(err
);
1203 skb_reserve(skb
, prepad
);
1204 skb_put(skb
, linear
);
1205 skb
->data_len
= len
- linear
;
1206 skb
->len
+= len
- linear
;
1211 static void tun_rx_batched(struct tun_struct
*tun
, struct tun_file
*tfile
,
1212 struct sk_buff
*skb
, int more
)
1214 struct sk_buff_head
*queue
= &tfile
->sk
.sk_write_queue
;
1215 struct sk_buff_head process_queue
;
1216 u32 rx_batched
= tun
->rx_batched
;
1219 if (!rx_batched
|| (!more
&& skb_queue_empty(queue
))) {
1221 netif_receive_skb(skb
);
1226 spin_lock(&queue
->lock
);
1227 if (!more
|| skb_queue_len(queue
) == rx_batched
) {
1228 __skb_queue_head_init(&process_queue
);
1229 skb_queue_splice_tail_init(queue
, &process_queue
);
1232 __skb_queue_tail(queue
, skb
);
1234 spin_unlock(&queue
->lock
);
1237 struct sk_buff
*nskb
;
1240 while ((nskb
= __skb_dequeue(&process_queue
)))
1241 netif_receive_skb(nskb
);
1242 netif_receive_skb(skb
);
1247 static bool tun_can_build_skb(struct tun_struct
*tun
, struct tun_file
*tfile
,
1248 int len
, int noblock
, bool zerocopy
)
1250 if ((tun
->flags
& TUN_TYPE_MASK
) != IFF_TAP
)
1253 if (tfile
->socket
.sk
->sk_sndbuf
!= INT_MAX
)
1262 if (SKB_DATA_ALIGN(len
+ TUN_RX_PAD
) +
1263 SKB_DATA_ALIGN(sizeof(struct skb_shared_info
)) > PAGE_SIZE
)
1269 static struct sk_buff
*tun_build_skb(struct tun_struct
*tun
,
1270 struct tun_file
*tfile
,
1271 struct iov_iter
*from
,
1272 struct virtio_net_hdr
*hdr
,
1273 int len
, int *generic_xdp
)
1275 struct page_frag
*alloc_frag
= &tfile
->alloc_frag
;
1276 struct sk_buff
*skb
;
1277 struct bpf_prog
*xdp_prog
;
1278 int buflen
= SKB_DATA_ALIGN(len
+ TUN_RX_PAD
) +
1279 SKB_DATA_ALIGN(sizeof(struct skb_shared_info
));
1280 unsigned int delta
= 0;
1283 bool xdp_xmit
= false;
1286 if (unlikely(!skb_page_frag_refill(buflen
, alloc_frag
, GFP_KERNEL
)))
1287 return ERR_PTR(-ENOMEM
);
1289 buf
= (char *)page_address(alloc_frag
->page
) + alloc_frag
->offset
;
1290 copied
= copy_page_from_iter(alloc_frag
->page
,
1291 alloc_frag
->offset
+ TUN_RX_PAD
,
1294 return ERR_PTR(-EFAULT
);
1302 xdp_prog
= rcu_dereference(tun
->xdp_prog
);
1303 if (xdp_prog
&& !*generic_xdp
) {
1304 struct xdp_buff xdp
;
1308 xdp
.data_hard_start
= buf
;
1309 xdp
.data
= buf
+ TUN_RX_PAD
;
1310 xdp
.data_end
= xdp
.data
+ len
;
1311 orig_data
= xdp
.data
;
1312 act
= bpf_prog_run_xdp(xdp_prog
, &xdp
);
1316 get_page(alloc_frag
->page
);
1317 alloc_frag
->offset
+= buflen
;
1318 err
= xdp_do_redirect(tun
->dev
, &xdp
, xdp_prog
);
1326 delta
= orig_data
- xdp
.data
;
1329 bpf_warn_invalid_xdp_action(act
);
1332 trace_xdp_exception(tun
->dev
, xdp_prog
, act
);
1339 skb
= build_skb(buf
, buflen
);
1342 return ERR_PTR(-ENOMEM
);
1345 skb_reserve(skb
, TUN_RX_PAD
- delta
);
1346 skb_put(skb
, len
+ delta
);
1347 get_page(alloc_frag
->page
);
1348 alloc_frag
->offset
+= buflen
;
1351 skb
->dev
= tun
->dev
;
1352 generic_xdp_tx(skb
, xdp_prog
);
1362 put_page(alloc_frag
->page
);
1365 this_cpu_inc(tun
->pcpu_stats
->rx_dropped
);
1369 /* Get packet from user space buffer */
1370 static ssize_t
tun_get_user(struct tun_struct
*tun
, struct tun_file
*tfile
,
1371 void *msg_control
, struct iov_iter
*from
,
1372 int noblock
, bool more
)
1374 struct tun_pi pi
= { 0, cpu_to_be16(ETH_P_IP
) };
1375 struct sk_buff
*skb
;
1376 size_t total_len
= iov_iter_count(from
);
1377 size_t len
= total_len
, align
= tun
->align
, linear
;
1378 struct virtio_net_hdr gso
= { 0 };
1379 struct tun_pcpu_stats
*stats
;
1382 bool zerocopy
= false;
1385 int generic_xdp
= 1;
1387 if (!(tun
->dev
->flags
& IFF_UP
))
1390 if (!(tun
->flags
& IFF_NO_PI
)) {
1391 if (len
< sizeof(pi
))
1395 if (!copy_from_iter_full(&pi
, sizeof(pi
), from
))
1399 if (tun
->flags
& IFF_VNET_HDR
) {
1400 int vnet_hdr_sz
= READ_ONCE(tun
->vnet_hdr_sz
);
1402 if (len
< vnet_hdr_sz
)
1406 if (!copy_from_iter_full(&gso
, sizeof(gso
), from
))
1409 if ((gso
.flags
& VIRTIO_NET_HDR_F_NEEDS_CSUM
) &&
1410 tun16_to_cpu(tun
, gso
.csum_start
) + tun16_to_cpu(tun
, gso
.csum_offset
) + 2 > tun16_to_cpu(tun
, gso
.hdr_len
))
1411 gso
.hdr_len
= cpu_to_tun16(tun
, tun16_to_cpu(tun
, gso
.csum_start
) + tun16_to_cpu(tun
, gso
.csum_offset
) + 2);
1413 if (tun16_to_cpu(tun
, gso
.hdr_len
) > len
)
1415 iov_iter_advance(from
, vnet_hdr_sz
- sizeof(gso
));
1418 if ((tun
->flags
& TUN_TYPE_MASK
) == IFF_TAP
) {
1419 align
+= NET_IP_ALIGN
;
1420 if (unlikely(len
< ETH_HLEN
||
1421 (gso
.hdr_len
&& tun16_to_cpu(tun
, gso
.hdr_len
) < ETH_HLEN
)))
1425 good_linear
= SKB_MAX_HEAD(align
);
1428 struct iov_iter i
= *from
;
1430 /* There are 256 bytes to be copied in skb, so there is
1431 * enough room for skb expand head in case it is used.
1432 * The rest of the buffer is mapped from userspace.
1434 copylen
= gso
.hdr_len
? tun16_to_cpu(tun
, gso
.hdr_len
) : GOODCOPY_LEN
;
1435 if (copylen
> good_linear
)
1436 copylen
= good_linear
;
1438 iov_iter_advance(&i
, copylen
);
1439 if (iov_iter_npages(&i
, INT_MAX
) <= MAX_SKB_FRAGS
)
1443 if (tun_can_build_skb(tun
, tfile
, len
, noblock
, zerocopy
)) {
1444 skb
= tun_build_skb(tun
, tfile
, from
, &gso
, len
, &generic_xdp
);
1446 this_cpu_inc(tun
->pcpu_stats
->rx_dropped
);
1447 return PTR_ERR(skb
);
1454 if (tun16_to_cpu(tun
, gso
.hdr_len
) > good_linear
)
1455 linear
= good_linear
;
1457 linear
= tun16_to_cpu(tun
, gso
.hdr_len
);
1460 skb
= tun_alloc_skb(tfile
, align
, copylen
, linear
, noblock
);
1462 if (PTR_ERR(skb
) != -EAGAIN
)
1463 this_cpu_inc(tun
->pcpu_stats
->rx_dropped
);
1464 return PTR_ERR(skb
);
1468 err
= zerocopy_sg_from_iter(skb
, from
);
1470 err
= skb_copy_datagram_from_iter(skb
, 0, from
, len
);
1473 this_cpu_inc(tun
->pcpu_stats
->rx_dropped
);
1479 if (virtio_net_hdr_to_skb(skb
, &gso
, tun_is_little_endian(tun
))) {
1480 this_cpu_inc(tun
->pcpu_stats
->rx_frame_errors
);
1485 switch (tun
->flags
& TUN_TYPE_MASK
) {
1487 if (tun
->flags
& IFF_NO_PI
) {
1488 switch (skb
->data
[0] & 0xf0) {
1490 pi
.proto
= htons(ETH_P_IP
);
1493 pi
.proto
= htons(ETH_P_IPV6
);
1496 this_cpu_inc(tun
->pcpu_stats
->rx_dropped
);
1502 skb_reset_mac_header(skb
);
1503 skb
->protocol
= pi
.proto
;
1504 skb
->dev
= tun
->dev
;
1507 skb
->protocol
= eth_type_trans(skb
, tun
->dev
);
1511 /* copy skb_ubuf_info for callback when skb has no error */
1513 skb_shinfo(skb
)->destructor_arg
= msg_control
;
1514 skb_shinfo(skb
)->tx_flags
|= SKBTX_DEV_ZEROCOPY
;
1515 skb_shinfo(skb
)->tx_flags
|= SKBTX_SHARED_FRAG
;
1516 } else if (msg_control
) {
1517 struct ubuf_info
*uarg
= msg_control
;
1518 uarg
->callback(uarg
, false);
1521 skb_reset_network_header(skb
);
1522 skb_probe_transport_header(skb
, 0);
1525 struct bpf_prog
*xdp_prog
;
1529 xdp_prog
= rcu_dereference(tun
->xdp_prog
);
1531 ret
= do_xdp_generic(xdp_prog
, skb
);
1532 if (ret
!= XDP_PASS
) {
1540 rxhash
= __skb_get_hash_symmetric(skb
);
1541 #ifndef CONFIG_4KSTACKS
1542 tun_rx_batched(tun
, tfile
, skb
, more
);
1547 stats
= get_cpu_ptr(tun
->pcpu_stats
);
1548 u64_stats_update_begin(&stats
->syncp
);
1549 stats
->rx_packets
++;
1550 stats
->rx_bytes
+= len
;
1551 u64_stats_update_end(&stats
->syncp
);
1554 tun_flow_update(tun
, rxhash
, tfile
);
1558 static ssize_t
tun_chr_write_iter(struct kiocb
*iocb
, struct iov_iter
*from
)
1560 struct file
*file
= iocb
->ki_filp
;
1561 struct tun_struct
*tun
= tun_get(file
);
1562 struct tun_file
*tfile
= file
->private_data
;
1568 result
= tun_get_user(tun
, tfile
, NULL
, from
,
1569 file
->f_flags
& O_NONBLOCK
, false);
1575 /* Put packet to the user space buffer */
1576 static ssize_t
tun_put_user(struct tun_struct
*tun
,
1577 struct tun_file
*tfile
,
1578 struct sk_buff
*skb
,
1579 struct iov_iter
*iter
)
1581 struct tun_pi pi
= { 0, skb
->protocol
};
1582 struct tun_pcpu_stats
*stats
;
1584 int vlan_offset
= 0;
1586 int vnet_hdr_sz
= 0;
1588 if (skb_vlan_tag_present(skb
))
1589 vlan_hlen
= VLAN_HLEN
;
1591 if (tun
->flags
& IFF_VNET_HDR
)
1592 vnet_hdr_sz
= READ_ONCE(tun
->vnet_hdr_sz
);
1594 total
= skb
->len
+ vlan_hlen
+ vnet_hdr_sz
;
1596 if (!(tun
->flags
& IFF_NO_PI
)) {
1597 if (iov_iter_count(iter
) < sizeof(pi
))
1600 total
+= sizeof(pi
);
1601 if (iov_iter_count(iter
) < total
) {
1602 /* Packet will be striped */
1603 pi
.flags
|= TUN_PKT_STRIP
;
1606 if (copy_to_iter(&pi
, sizeof(pi
), iter
) != sizeof(pi
))
1611 struct virtio_net_hdr gso
;
1613 if (iov_iter_count(iter
) < vnet_hdr_sz
)
1616 if (virtio_net_hdr_from_skb(skb
, &gso
,
1617 tun_is_little_endian(tun
), true)) {
1618 struct skb_shared_info
*sinfo
= skb_shinfo(skb
);
1619 pr_err("unexpected GSO type: "
1620 "0x%x, gso_size %d, hdr_len %d\n",
1621 sinfo
->gso_type
, tun16_to_cpu(tun
, gso
.gso_size
),
1622 tun16_to_cpu(tun
, gso
.hdr_len
));
1623 print_hex_dump(KERN_ERR
, "tun: ",
1626 min((int)tun16_to_cpu(tun
, gso
.hdr_len
), 64), true);
1631 if (copy_to_iter(&gso
, sizeof(gso
), iter
) != sizeof(gso
))
1634 iov_iter_advance(iter
, vnet_hdr_sz
- sizeof(gso
));
1640 __be16 h_vlan_proto
;
1644 veth
.h_vlan_proto
= skb
->vlan_proto
;
1645 veth
.h_vlan_TCI
= htons(skb_vlan_tag_get(skb
));
1647 vlan_offset
= offsetof(struct vlan_ethhdr
, h_vlan_proto
);
1649 ret
= skb_copy_datagram_iter(skb
, 0, iter
, vlan_offset
);
1650 if (ret
|| !iov_iter_count(iter
))
1653 ret
= copy_to_iter(&veth
, sizeof(veth
), iter
);
1654 if (ret
!= sizeof(veth
) || !iov_iter_count(iter
))
1658 skb_copy_datagram_iter(skb
, vlan_offset
, iter
, skb
->len
- vlan_offset
);
1661 /* caller is in process context, */
1662 stats
= get_cpu_ptr(tun
->pcpu_stats
);
1663 u64_stats_update_begin(&stats
->syncp
);
1664 stats
->tx_packets
++;
1665 stats
->tx_bytes
+= skb
->len
+ vlan_hlen
;
1666 u64_stats_update_end(&stats
->syncp
);
1667 put_cpu_ptr(tun
->pcpu_stats
);
1672 static struct sk_buff
*tun_ring_recv(struct tun_file
*tfile
, int noblock
,
1675 DECLARE_WAITQUEUE(wait
, current
);
1676 struct sk_buff
*skb
= NULL
;
1679 skb
= skb_array_consume(&tfile
->tx_array
);
1687 add_wait_queue(&tfile
->wq
.wait
, &wait
);
1688 current
->state
= TASK_INTERRUPTIBLE
;
1691 skb
= skb_array_consume(&tfile
->tx_array
);
1694 if (signal_pending(current
)) {
1695 error
= -ERESTARTSYS
;
1698 if (tfile
->socket
.sk
->sk_shutdown
& RCV_SHUTDOWN
) {
1706 current
->state
= TASK_RUNNING
;
1707 remove_wait_queue(&tfile
->wq
.wait
, &wait
);
1714 static ssize_t
tun_do_read(struct tun_struct
*tun
, struct tun_file
*tfile
,
1715 struct iov_iter
*to
,
1716 int noblock
, struct sk_buff
*skb
)
1721 tun_debug(KERN_INFO
, tun
, "tun_do_read\n");
1723 if (!iov_iter_count(to
))
1727 /* Read frames from ring */
1728 skb
= tun_ring_recv(tfile
, noblock
, &err
);
1733 ret
= tun_put_user(tun
, tfile
, skb
, to
);
1734 if (unlikely(ret
< 0))
1742 static ssize_t
tun_chr_read_iter(struct kiocb
*iocb
, struct iov_iter
*to
)
1744 struct file
*file
= iocb
->ki_filp
;
1745 struct tun_file
*tfile
= file
->private_data
;
1746 struct tun_struct
*tun
= __tun_get(tfile
);
1747 ssize_t len
= iov_iter_count(to
), ret
;
1751 ret
= tun_do_read(tun
, tfile
, to
, file
->f_flags
& O_NONBLOCK
, NULL
);
1752 ret
= min_t(ssize_t
, ret
, len
);
1759 static void tun_free_netdev(struct net_device
*dev
)
1761 struct tun_struct
*tun
= netdev_priv(dev
);
1763 BUG_ON(!(list_empty(&tun
->disabled
)));
1764 free_percpu(tun
->pcpu_stats
);
1765 tun_flow_uninit(tun
);
1766 security_tun_dev_free_security(tun
->security
);
1769 static void tun_setup(struct net_device
*dev
)
1771 struct tun_struct
*tun
= netdev_priv(dev
);
1773 tun
->owner
= INVALID_UID
;
1774 tun
->group
= INVALID_GID
;
1776 dev
->ethtool_ops
= &tun_ethtool_ops
;
1777 dev
->needs_free_netdev
= true;
1778 dev
->priv_destructor
= tun_free_netdev
;
1779 /* We prefer our own queue length */
1780 dev
->tx_queue_len
= TUN_READQ_SIZE
;
1783 /* Trivial set of netlink ops to allow deleting tun or tap
1784 * device with netlink.
1786 static int tun_validate(struct nlattr
*tb
[], struct nlattr
*data
[],
1787 struct netlink_ext_ack
*extack
)
1792 static struct rtnl_link_ops tun_link_ops __read_mostly
= {
1794 .priv_size
= sizeof(struct tun_struct
),
1796 .validate
= tun_validate
,
1799 static void tun_sock_write_space(struct sock
*sk
)
1801 struct tun_file
*tfile
;
1802 wait_queue_head_t
*wqueue
;
1804 if (!sock_writeable(sk
))
1807 if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE
, &sk
->sk_socket
->flags
))
1810 wqueue
= sk_sleep(sk
);
1811 if (wqueue
&& waitqueue_active(wqueue
))
1812 wake_up_interruptible_sync_poll(wqueue
, POLLOUT
|
1813 POLLWRNORM
| POLLWRBAND
);
1815 tfile
= container_of(sk
, struct tun_file
, sk
);
1816 kill_fasync(&tfile
->fasync
, SIGIO
, POLL_OUT
);
1819 static int tun_sendmsg(struct socket
*sock
, struct msghdr
*m
, size_t total_len
)
1822 struct tun_file
*tfile
= container_of(sock
, struct tun_file
, socket
);
1823 struct tun_struct
*tun
= __tun_get(tfile
);
1828 ret
= tun_get_user(tun
, tfile
, m
->msg_control
, &m
->msg_iter
,
1829 m
->msg_flags
& MSG_DONTWAIT
,
1830 m
->msg_flags
& MSG_MORE
);
1835 static int tun_recvmsg(struct socket
*sock
, struct msghdr
*m
, size_t total_len
,
1838 struct tun_file
*tfile
= container_of(sock
, struct tun_file
, socket
);
1839 struct tun_struct
*tun
= __tun_get(tfile
);
1845 if (flags
& ~(MSG_DONTWAIT
|MSG_TRUNC
|MSG_ERRQUEUE
)) {
1849 if (flags
& MSG_ERRQUEUE
) {
1850 ret
= sock_recv_errqueue(sock
->sk
, m
, total_len
,
1851 SOL_PACKET
, TUN_TX_TIMESTAMP
);
1854 ret
= tun_do_read(tun
, tfile
, &m
->msg_iter
, flags
& MSG_DONTWAIT
,
1856 if (ret
> (ssize_t
)total_len
) {
1857 m
->msg_flags
|= MSG_TRUNC
;
1858 ret
= flags
& MSG_TRUNC
? ret
: total_len
;
1865 static int tun_peek_len(struct socket
*sock
)
1867 struct tun_file
*tfile
= container_of(sock
, struct tun_file
, socket
);
1868 struct tun_struct
*tun
;
1871 tun
= __tun_get(tfile
);
1875 ret
= skb_array_peek_len(&tfile
->tx_array
);
1881 /* Ops structure to mimic raw sockets with tun */
1882 static const struct proto_ops tun_socket_ops
= {
1883 .peek_len
= tun_peek_len
,
1884 .sendmsg
= tun_sendmsg
,
1885 .recvmsg
= tun_recvmsg
,
1888 static struct proto tun_proto
= {
1890 .owner
= THIS_MODULE
,
1891 .obj_size
= sizeof(struct tun_file
),
1894 static int tun_flags(struct tun_struct
*tun
)
1896 return tun
->flags
& (TUN_FEATURES
| IFF_PERSIST
| IFF_TUN
| IFF_TAP
);
1899 static ssize_t
tun_show_flags(struct device
*dev
, struct device_attribute
*attr
,
1902 struct tun_struct
*tun
= netdev_priv(to_net_dev(dev
));
1903 return sprintf(buf
, "0x%x\n", tun_flags(tun
));
1906 static ssize_t
tun_show_owner(struct device
*dev
, struct device_attribute
*attr
,
1909 struct tun_struct
*tun
= netdev_priv(to_net_dev(dev
));
1910 return uid_valid(tun
->owner
)?
1911 sprintf(buf
, "%u\n",
1912 from_kuid_munged(current_user_ns(), tun
->owner
)):
1913 sprintf(buf
, "-1\n");
1916 static ssize_t
tun_show_group(struct device
*dev
, struct device_attribute
*attr
,
1919 struct tun_struct
*tun
= netdev_priv(to_net_dev(dev
));
1920 return gid_valid(tun
->group
) ?
1921 sprintf(buf
, "%u\n",
1922 from_kgid_munged(current_user_ns(), tun
->group
)):
1923 sprintf(buf
, "-1\n");
1926 static DEVICE_ATTR(tun_flags
, 0444, tun_show_flags
, NULL
);
1927 static DEVICE_ATTR(owner
, 0444, tun_show_owner
, NULL
);
1928 static DEVICE_ATTR(group
, 0444, tun_show_group
, NULL
);
1930 static struct attribute
*tun_dev_attrs
[] = {
1931 &dev_attr_tun_flags
.attr
,
1932 &dev_attr_owner
.attr
,
1933 &dev_attr_group
.attr
,
1937 static const struct attribute_group tun_attr_group
= {
1938 .attrs
= tun_dev_attrs
1941 static int tun_set_iff(struct net
*net
, struct file
*file
, struct ifreq
*ifr
)
1943 struct tun_struct
*tun
;
1944 struct tun_file
*tfile
= file
->private_data
;
1945 struct net_device
*dev
;
1948 if (tfile
->detached
)
1951 dev
= __dev_get_by_name(net
, ifr
->ifr_name
);
1953 if (ifr
->ifr_flags
& IFF_TUN_EXCL
)
1955 if ((ifr
->ifr_flags
& IFF_TUN
) && dev
->netdev_ops
== &tun_netdev_ops
)
1956 tun
= netdev_priv(dev
);
1957 else if ((ifr
->ifr_flags
& IFF_TAP
) && dev
->netdev_ops
== &tap_netdev_ops
)
1958 tun
= netdev_priv(dev
);
1962 if (!!(ifr
->ifr_flags
& IFF_MULTI_QUEUE
) !=
1963 !!(tun
->flags
& IFF_MULTI_QUEUE
))
1966 if (tun_not_capable(tun
))
1968 err
= security_tun_dev_open(tun
->security
);
1972 err
= tun_attach(tun
, file
, ifr
->ifr_flags
& IFF_NOFILTER
);
1976 if (tun
->flags
& IFF_MULTI_QUEUE
&&
1977 (tun
->numqueues
+ tun
->numdisabled
> 1)) {
1978 /* One or more queue has already been attached, no need
1979 * to initialize the device again.
1986 unsigned long flags
= 0;
1987 int queues
= ifr
->ifr_flags
& IFF_MULTI_QUEUE
?
1990 if (!ns_capable(net
->user_ns
, CAP_NET_ADMIN
))
1992 err
= security_tun_dev_create();
1997 if (ifr
->ifr_flags
& IFF_TUN
) {
2001 } else if (ifr
->ifr_flags
& IFF_TAP
) {
2009 name
= ifr
->ifr_name
;
2011 dev
= alloc_netdev_mqs(sizeof(struct tun_struct
), name
,
2012 NET_NAME_UNKNOWN
, tun_setup
, queues
,
2018 dev_net_set(dev
, net
);
2019 dev
->rtnl_link_ops
= &tun_link_ops
;
2020 dev
->ifindex
= tfile
->ifindex
;
2021 dev
->sysfs_groups
[0] = &tun_attr_group
;
2023 tun
= netdev_priv(dev
);
2026 tun
->txflt
.count
= 0;
2027 tun
->vnet_hdr_sz
= sizeof(struct virtio_net_hdr
);
2029 tun
->align
= NET_SKB_PAD
;
2030 tun
->filter_attached
= false;
2031 tun
->sndbuf
= tfile
->socket
.sk
->sk_sndbuf
;
2032 tun
->rx_batched
= 0;
2034 tun
->pcpu_stats
= netdev_alloc_pcpu_stats(struct tun_pcpu_stats
);
2035 if (!tun
->pcpu_stats
) {
2040 spin_lock_init(&tun
->lock
);
2042 err
= security_tun_dev_alloc_security(&tun
->security
);
2049 dev
->hw_features
= NETIF_F_SG
| NETIF_F_FRAGLIST
|
2050 TUN_USER_FEATURES
| NETIF_F_HW_VLAN_CTAG_TX
|
2051 NETIF_F_HW_VLAN_STAG_TX
;
2052 dev
->features
= dev
->hw_features
| NETIF_F_LLTX
;
2053 dev
->vlan_features
= dev
->features
&
2054 ~(NETIF_F_HW_VLAN_CTAG_TX
|
2055 NETIF_F_HW_VLAN_STAG_TX
);
2057 INIT_LIST_HEAD(&tun
->disabled
);
2058 err
= tun_attach(tun
, file
, false);
2062 err
= register_netdevice(tun
->dev
);
2067 netif_carrier_on(tun
->dev
);
2069 tun_debug(KERN_INFO
, tun
, "tun_set_iff\n");
2071 tun
->flags
= (tun
->flags
& ~TUN_FEATURES
) |
2072 (ifr
->ifr_flags
& TUN_FEATURES
);
2074 /* Make sure persistent devices do not get stuck in
2077 if (netif_running(tun
->dev
))
2078 netif_tx_wake_all_queues(tun
->dev
);
2080 strcpy(ifr
->ifr_name
, tun
->dev
->name
);
2084 tun_detach_all(dev
);
2086 tun_flow_uninit(tun
);
2087 security_tun_dev_free_security(tun
->security
);
2089 free_percpu(tun
->pcpu_stats
);
2095 static void tun_get_iff(struct net
*net
, struct tun_struct
*tun
,
2098 tun_debug(KERN_INFO
, tun
, "tun_get_iff\n");
2100 strcpy(ifr
->ifr_name
, tun
->dev
->name
);
2102 ifr
->ifr_flags
= tun_flags(tun
);
2106 /* This is like a cut-down ethtool ops, except done via tun fd so no
2107 * privs required. */
2108 static int set_offload(struct tun_struct
*tun
, unsigned long arg
)
2110 netdev_features_t features
= 0;
2112 if (arg
& TUN_F_CSUM
) {
2113 features
|= NETIF_F_HW_CSUM
;
2116 if (arg
& (TUN_F_TSO4
|TUN_F_TSO6
)) {
2117 if (arg
& TUN_F_TSO_ECN
) {
2118 features
|= NETIF_F_TSO_ECN
;
2119 arg
&= ~TUN_F_TSO_ECN
;
2121 if (arg
& TUN_F_TSO4
)
2122 features
|= NETIF_F_TSO
;
2123 if (arg
& TUN_F_TSO6
)
2124 features
|= NETIF_F_TSO6
;
2125 arg
&= ~(TUN_F_TSO4
|TUN_F_TSO6
);
2129 /* This gives the user a way to test for new features in future by
2130 * trying to set them. */
2134 tun
->set_features
= features
;
2135 tun
->dev
->wanted_features
&= ~TUN_USER_FEATURES
;
2136 tun
->dev
->wanted_features
|= features
;
2137 netdev_update_features(tun
->dev
);
2142 static void tun_detach_filter(struct tun_struct
*tun
, int n
)
2145 struct tun_file
*tfile
;
2147 for (i
= 0; i
< n
; i
++) {
2148 tfile
= rtnl_dereference(tun
->tfiles
[i
]);
2149 lock_sock(tfile
->socket
.sk
);
2150 sk_detach_filter(tfile
->socket
.sk
);
2151 release_sock(tfile
->socket
.sk
);
2154 tun
->filter_attached
= false;
2157 static int tun_attach_filter(struct tun_struct
*tun
)
2160 struct tun_file
*tfile
;
2162 for (i
= 0; i
< tun
->numqueues
; i
++) {
2163 tfile
= rtnl_dereference(tun
->tfiles
[i
]);
2164 lock_sock(tfile
->socket
.sk
);
2165 ret
= sk_attach_filter(&tun
->fprog
, tfile
->socket
.sk
);
2166 release_sock(tfile
->socket
.sk
);
2168 tun_detach_filter(tun
, i
);
2173 tun
->filter_attached
= true;
2177 static void tun_set_sndbuf(struct tun_struct
*tun
)
2179 struct tun_file
*tfile
;
2182 for (i
= 0; i
< tun
->numqueues
; i
++) {
2183 tfile
= rtnl_dereference(tun
->tfiles
[i
]);
2184 tfile
->socket
.sk
->sk_sndbuf
= tun
->sndbuf
;
2188 static int tun_set_queue(struct file
*file
, struct ifreq
*ifr
)
2190 struct tun_file
*tfile
= file
->private_data
;
2191 struct tun_struct
*tun
;
2196 if (ifr
->ifr_flags
& IFF_ATTACH_QUEUE
) {
2197 tun
= tfile
->detached
;
2202 ret
= security_tun_dev_attach_queue(tun
->security
);
2205 ret
= tun_attach(tun
, file
, false);
2206 } else if (ifr
->ifr_flags
& IFF_DETACH_QUEUE
) {
2207 tun
= rtnl_dereference(tfile
->tun
);
2208 if (!tun
|| !(tun
->flags
& IFF_MULTI_QUEUE
) || tfile
->detached
)
2211 __tun_detach(tfile
, false);
2220 static long __tun_chr_ioctl(struct file
*file
, unsigned int cmd
,
2221 unsigned long arg
, int ifreq_len
)
2223 struct tun_file
*tfile
= file
->private_data
;
2224 struct tun_struct
*tun
;
2225 void __user
* argp
= (void __user
*)arg
;
2231 unsigned int ifindex
;
2235 if (cmd
== TUNSETIFF
|| cmd
== TUNSETQUEUE
|| _IOC_TYPE(cmd
) == SOCK_IOC_TYPE
) {
2236 if (copy_from_user(&ifr
, argp
, ifreq_len
))
2239 memset(&ifr
, 0, sizeof(ifr
));
2241 if (cmd
== TUNGETFEATURES
) {
2242 /* Currently this just means: "what IFF flags are valid?".
2243 * This is needed because we never checked for invalid flags on
2246 return put_user(IFF_TUN
| IFF_TAP
| TUN_FEATURES
,
2247 (unsigned int __user
*)argp
);
2248 } else if (cmd
== TUNSETQUEUE
)
2249 return tun_set_queue(file
, &ifr
);
2254 tun
= __tun_get(tfile
);
2255 if (cmd
== TUNSETIFF
) {
2260 ifr
.ifr_name
[IFNAMSIZ
-1] = '\0';
2262 ret
= tun_set_iff(sock_net(&tfile
->sk
), file
, &ifr
);
2267 if (copy_to_user(argp
, &ifr
, ifreq_len
))
2271 if (cmd
== TUNSETIFINDEX
) {
2277 if (copy_from_user(&ifindex
, argp
, sizeof(ifindex
)))
2281 tfile
->ifindex
= ifindex
;
2289 tun_debug(KERN_INFO
, tun
, "tun_chr_ioctl cmd %u\n", cmd
);
2294 tun_get_iff(current
->nsproxy
->net_ns
, tun
, &ifr
);
2296 if (tfile
->detached
)
2297 ifr
.ifr_flags
|= IFF_DETACH_QUEUE
;
2298 if (!tfile
->socket
.sk
->sk_filter
)
2299 ifr
.ifr_flags
|= IFF_NOFILTER
;
2301 if (copy_to_user(argp
, &ifr
, ifreq_len
))
2306 /* Disable/Enable checksum */
2308 /* [unimplemented] */
2309 tun_debug(KERN_INFO
, tun
, "ignored: set checksum %s\n",
2310 arg
? "disabled" : "enabled");
2314 /* Disable/Enable persist mode. Keep an extra reference to the
2315 * module to prevent the module being unprobed.
2317 if (arg
&& !(tun
->flags
& IFF_PERSIST
)) {
2318 tun
->flags
|= IFF_PERSIST
;
2319 __module_get(THIS_MODULE
);
2321 if (!arg
&& (tun
->flags
& IFF_PERSIST
)) {
2322 tun
->flags
&= ~IFF_PERSIST
;
2323 module_put(THIS_MODULE
);
2326 tun_debug(KERN_INFO
, tun
, "persist %s\n",
2327 arg
? "enabled" : "disabled");
2331 /* Set owner of the device */
2332 owner
= make_kuid(current_user_ns(), arg
);
2333 if (!uid_valid(owner
)) {
2338 tun_debug(KERN_INFO
, tun
, "owner set to %u\n",
2339 from_kuid(&init_user_ns
, tun
->owner
));
2343 /* Set group of the device */
2344 group
= make_kgid(current_user_ns(), arg
);
2345 if (!gid_valid(group
)) {
2350 tun_debug(KERN_INFO
, tun
, "group set to %u\n",
2351 from_kgid(&init_user_ns
, tun
->group
));
2355 /* Only allow setting the type when the interface is down */
2356 if (tun
->dev
->flags
& IFF_UP
) {
2357 tun_debug(KERN_INFO
, tun
,
2358 "Linktype set failed because interface is up\n");
2361 tun
->dev
->type
= (int) arg
;
2362 tun_debug(KERN_INFO
, tun
, "linktype set to %d\n",
2374 ret
= set_offload(tun
, arg
);
2377 case TUNSETTXFILTER
:
2378 /* Can be set only for TAPs */
2380 if ((tun
->flags
& TUN_TYPE_MASK
) != IFF_TAP
)
2382 ret
= update_filter(&tun
->txflt
, (void __user
*)arg
);
2386 /* Get hw address */
2387 memcpy(ifr
.ifr_hwaddr
.sa_data
, tun
->dev
->dev_addr
, ETH_ALEN
);
2388 ifr
.ifr_hwaddr
.sa_family
= tun
->dev
->type
;
2389 if (copy_to_user(argp
, &ifr
, ifreq_len
))
2394 /* Set hw address */
2395 tun_debug(KERN_DEBUG
, tun
, "set hw address: %pM\n",
2396 ifr
.ifr_hwaddr
.sa_data
);
2398 ret
= dev_set_mac_address(tun
->dev
, &ifr
.ifr_hwaddr
);
2402 sndbuf
= tfile
->socket
.sk
->sk_sndbuf
;
2403 if (copy_to_user(argp
, &sndbuf
, sizeof(sndbuf
)))
2408 if (copy_from_user(&sndbuf
, argp
, sizeof(sndbuf
))) {
2413 tun
->sndbuf
= sndbuf
;
2414 tun_set_sndbuf(tun
);
2417 case TUNGETVNETHDRSZ
:
2418 vnet_hdr_sz
= tun
->vnet_hdr_sz
;
2419 if (copy_to_user(argp
, &vnet_hdr_sz
, sizeof(vnet_hdr_sz
)))
2423 case TUNSETVNETHDRSZ
:
2424 if (copy_from_user(&vnet_hdr_sz
, argp
, sizeof(vnet_hdr_sz
))) {
2428 if (vnet_hdr_sz
< (int)sizeof(struct virtio_net_hdr
)) {
2433 tun
->vnet_hdr_sz
= vnet_hdr_sz
;
2437 le
= !!(tun
->flags
& TUN_VNET_LE
);
2438 if (put_user(le
, (int __user
*)argp
))
2443 if (get_user(le
, (int __user
*)argp
)) {
2448 tun
->flags
|= TUN_VNET_LE
;
2450 tun
->flags
&= ~TUN_VNET_LE
;
2454 ret
= tun_get_vnet_be(tun
, argp
);
2458 ret
= tun_set_vnet_be(tun
, argp
);
2461 case TUNATTACHFILTER
:
2462 /* Can be set only for TAPs */
2464 if ((tun
->flags
& TUN_TYPE_MASK
) != IFF_TAP
)
2467 if (copy_from_user(&tun
->fprog
, argp
, sizeof(tun
->fprog
)))
2470 ret
= tun_attach_filter(tun
);
2473 case TUNDETACHFILTER
:
2474 /* Can be set only for TAPs */
2476 if ((tun
->flags
& TUN_TYPE_MASK
) != IFF_TAP
)
2479 tun_detach_filter(tun
, tun
->numqueues
);
2484 if ((tun
->flags
& TUN_TYPE_MASK
) != IFF_TAP
)
2487 if (copy_to_user(argp
, &tun
->fprog
, sizeof(tun
->fprog
)))
2504 static long tun_chr_ioctl(struct file
*file
,
2505 unsigned int cmd
, unsigned long arg
)
2507 return __tun_chr_ioctl(file
, cmd
, arg
, sizeof (struct ifreq
));
2510 #ifdef CONFIG_COMPAT
2511 static long tun_chr_compat_ioctl(struct file
*file
,
2512 unsigned int cmd
, unsigned long arg
)
2517 case TUNSETTXFILTER
:
2522 arg
= (unsigned long)compat_ptr(arg
);
2525 arg
= (compat_ulong_t
)arg
;
2530 * compat_ifreq is shorter than ifreq, so we must not access beyond
2531 * the end of that structure. All fields that are used in this
2532 * driver are compatible though, we don't need to convert the
2535 return __tun_chr_ioctl(file
, cmd
, arg
, sizeof(struct compat_ifreq
));
2537 #endif /* CONFIG_COMPAT */
2539 static int tun_chr_fasync(int fd
, struct file
*file
, int on
)
2541 struct tun_file
*tfile
= file
->private_data
;
2544 if ((ret
= fasync_helper(fd
, file
, on
, &tfile
->fasync
)) < 0)
2548 __f_setown(file
, task_pid(current
), PIDTYPE_PID
, 0);
2549 tfile
->flags
|= TUN_FASYNC
;
2551 tfile
->flags
&= ~TUN_FASYNC
;
2557 static int tun_chr_open(struct inode
*inode
, struct file
* file
)
2559 struct net
*net
= current
->nsproxy
->net_ns
;
2560 struct tun_file
*tfile
;
2562 DBG1(KERN_INFO
, "tunX: tun_chr_open\n");
2564 tfile
= (struct tun_file
*)sk_alloc(net
, AF_UNSPEC
, GFP_KERNEL
,
2568 RCU_INIT_POINTER(tfile
->tun
, NULL
);
2572 init_waitqueue_head(&tfile
->wq
.wait
);
2573 RCU_INIT_POINTER(tfile
->socket
.wq
, &tfile
->wq
);
2575 tfile
->socket
.file
= file
;
2576 tfile
->socket
.ops
= &tun_socket_ops
;
2578 sock_init_data(&tfile
->socket
, &tfile
->sk
);
2580 tfile
->sk
.sk_write_space
= tun_sock_write_space
;
2581 tfile
->sk
.sk_sndbuf
= INT_MAX
;
2583 tfile
->alloc_frag
.page
= NULL
;
2585 file
->private_data
= tfile
;
2586 INIT_LIST_HEAD(&tfile
->next
);
2588 sock_set_flag(&tfile
->sk
, SOCK_ZEROCOPY
);
2593 static int tun_chr_close(struct inode
*inode
, struct file
*file
)
2595 struct tun_file
*tfile
= file
->private_data
;
2597 tun_detach(tfile
, true);
2602 #ifdef CONFIG_PROC_FS
2603 static void tun_chr_show_fdinfo(struct seq_file
*m
, struct file
*f
)
2605 struct tun_struct
*tun
;
2608 memset(&ifr
, 0, sizeof(ifr
));
2613 tun_get_iff(current
->nsproxy
->net_ns
, tun
, &ifr
);
2619 seq_printf(m
, "iff:\t%s\n", ifr
.ifr_name
);
2623 static const struct file_operations tun_fops
= {
2624 .owner
= THIS_MODULE
,
2625 .llseek
= no_llseek
,
2626 .read_iter
= tun_chr_read_iter
,
2627 .write_iter
= tun_chr_write_iter
,
2628 .poll
= tun_chr_poll
,
2629 .unlocked_ioctl
= tun_chr_ioctl
,
2630 #ifdef CONFIG_COMPAT
2631 .compat_ioctl
= tun_chr_compat_ioctl
,
2633 .open
= tun_chr_open
,
2634 .release
= tun_chr_close
,
2635 .fasync
= tun_chr_fasync
,
2636 #ifdef CONFIG_PROC_FS
2637 .show_fdinfo
= tun_chr_show_fdinfo
,
2641 static struct miscdevice tun_miscdev
= {
2644 .nodename
= "net/tun",
2648 /* ethtool interface */
2650 static int tun_get_link_ksettings(struct net_device
*dev
,
2651 struct ethtool_link_ksettings
*cmd
)
2653 ethtool_link_ksettings_zero_link_mode(cmd
, supported
);
2654 ethtool_link_ksettings_zero_link_mode(cmd
, advertising
);
2655 cmd
->base
.speed
= SPEED_10
;
2656 cmd
->base
.duplex
= DUPLEX_FULL
;
2657 cmd
->base
.port
= PORT_TP
;
2658 cmd
->base
.phy_address
= 0;
2659 cmd
->base
.autoneg
= AUTONEG_DISABLE
;
2663 static void tun_get_drvinfo(struct net_device
*dev
, struct ethtool_drvinfo
*info
)
2665 struct tun_struct
*tun
= netdev_priv(dev
);
2667 strlcpy(info
->driver
, DRV_NAME
, sizeof(info
->driver
));
2668 strlcpy(info
->version
, DRV_VERSION
, sizeof(info
->version
));
2670 switch (tun
->flags
& TUN_TYPE_MASK
) {
2672 strlcpy(info
->bus_info
, "tun", sizeof(info
->bus_info
));
2675 strlcpy(info
->bus_info
, "tap", sizeof(info
->bus_info
));
2680 static u32
tun_get_msglevel(struct net_device
*dev
)
2683 struct tun_struct
*tun
= netdev_priv(dev
);
2690 static void tun_set_msglevel(struct net_device
*dev
, u32 value
)
2693 struct tun_struct
*tun
= netdev_priv(dev
);
2698 static int tun_get_coalesce(struct net_device
*dev
,
2699 struct ethtool_coalesce
*ec
)
2701 struct tun_struct
*tun
= netdev_priv(dev
);
2703 ec
->rx_max_coalesced_frames
= tun
->rx_batched
;
2708 static int tun_set_coalesce(struct net_device
*dev
,
2709 struct ethtool_coalesce
*ec
)
2711 struct tun_struct
*tun
= netdev_priv(dev
);
2713 if (ec
->rx_max_coalesced_frames
> NAPI_POLL_WEIGHT
)
2714 tun
->rx_batched
= NAPI_POLL_WEIGHT
;
2716 tun
->rx_batched
= ec
->rx_max_coalesced_frames
;
2721 static const struct ethtool_ops tun_ethtool_ops
= {
2722 .get_drvinfo
= tun_get_drvinfo
,
2723 .get_msglevel
= tun_get_msglevel
,
2724 .set_msglevel
= tun_set_msglevel
,
2725 .get_link
= ethtool_op_get_link
,
2726 .get_ts_info
= ethtool_op_get_ts_info
,
2727 .get_coalesce
= tun_get_coalesce
,
2728 .set_coalesce
= tun_set_coalesce
,
2729 .get_link_ksettings
= tun_get_link_ksettings
,
2732 static int tun_queue_resize(struct tun_struct
*tun
)
2734 struct net_device
*dev
= tun
->dev
;
2735 struct tun_file
*tfile
;
2736 struct skb_array
**arrays
;
2737 int n
= tun
->numqueues
+ tun
->numdisabled
;
2740 arrays
= kmalloc(sizeof *arrays
* n
, GFP_KERNEL
);
2744 for (i
= 0; i
< tun
->numqueues
; i
++) {
2745 tfile
= rtnl_dereference(tun
->tfiles
[i
]);
2746 arrays
[i
] = &tfile
->tx_array
;
2748 list_for_each_entry(tfile
, &tun
->disabled
, next
)
2749 arrays
[i
++] = &tfile
->tx_array
;
2751 ret
= skb_array_resize_multiple(arrays
, n
,
2752 dev
->tx_queue_len
, GFP_KERNEL
);
2758 static int tun_device_event(struct notifier_block
*unused
,
2759 unsigned long event
, void *ptr
)
2761 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
2762 struct tun_struct
*tun
= netdev_priv(dev
);
2764 if (dev
->rtnl_link_ops
!= &tun_link_ops
)
2768 case NETDEV_CHANGE_TX_QUEUE_LEN
:
2769 if (tun_queue_resize(tun
))
2779 static struct notifier_block tun_notifier_block __read_mostly
= {
2780 .notifier_call
= tun_device_event
,
2783 static int __init
tun_init(void)
2787 pr_info("%s, %s\n", DRV_DESCRIPTION
, DRV_VERSION
);
2789 ret
= rtnl_link_register(&tun_link_ops
);
2791 pr_err("Can't register link_ops\n");
2795 ret
= misc_register(&tun_miscdev
);
2797 pr_err("Can't register misc device %d\n", TUN_MINOR
);
2801 ret
= register_netdevice_notifier(&tun_notifier_block
);
2803 pr_err("Can't register netdevice notifier\n");
2810 misc_deregister(&tun_miscdev
);
2812 rtnl_link_unregister(&tun_link_ops
);
2817 static void tun_cleanup(void)
2819 misc_deregister(&tun_miscdev
);
2820 rtnl_link_unregister(&tun_link_ops
);
2821 unregister_netdevice_notifier(&tun_notifier_block
);
2824 /* Get an underlying socket object from tun file. Returns error unless file is
2825 * attached to a device. The returned object works like a packet socket, it
2826 * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
2827 * holding a reference to the file for as long as the socket is in use. */
2828 struct socket
*tun_get_socket(struct file
*file
)
2830 struct tun_file
*tfile
;
2831 if (file
->f_op
!= &tun_fops
)
2832 return ERR_PTR(-EINVAL
);
2833 tfile
= file
->private_data
;
2835 return ERR_PTR(-EBADFD
);
2836 return &tfile
->socket
;
2838 EXPORT_SYMBOL_GPL(tun_get_socket
);
2840 struct skb_array
*tun_get_skb_array(struct file
*file
)
2842 struct tun_file
*tfile
;
2844 if (file
->f_op
!= &tun_fops
)
2845 return ERR_PTR(-EINVAL
);
2846 tfile
= file
->private_data
;
2848 return ERR_PTR(-EBADFD
);
2849 return &tfile
->tx_array
;
2851 EXPORT_SYMBOL_GPL(tun_get_skb_array
);
2853 module_init(tun_init
);
2854 module_exit(tun_cleanup
);
2855 MODULE_DESCRIPTION(DRV_DESCRIPTION
);
2856 MODULE_AUTHOR(DRV_COPYRIGHT
);
2857 MODULE_LICENSE("GPL");
2858 MODULE_ALIAS_MISCDEV(TUN_MINOR
);
2859 MODULE_ALIAS("devname:net/tun");