Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * TUN - Universal TUN/TAP device driver. | |
3 | * Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License as published by | |
7 | * the Free Software Foundation; either version 2 of the License, or | |
8 | * (at your option) any later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $ | |
16 | */ | |
17 | ||
18 | /* | |
19 | * Changes: | |
20 | * | |
ff4cc3ac MK |
21 | * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14 |
22 | * Add TUNSETLINK ioctl to set the link encapsulation | |
23 | * | |
1da177e4 | 24 | * Mark Smith <markzzzsmith@yahoo.com.au> |
344dc8ed | 25 | * Use eth_random_addr() for tap MAC address. |
1da177e4 LT |
26 | * |
27 | * Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20 | |
28 | * Fixes in packet dropping, queue length setting and queue wakeup. | |
29 | * Increased default tx queue length. | |
30 | * Added ethtool API. | |
31 | * Minor cleanups | |
32 | * | |
33 | * Daniel Podlejski <underley@underley.eu.org> | |
34 | * Modifications for 2.3.99-pre5 kernel. | |
35 | */ | |
36 | ||
6b8a66ee JP |
37 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
38 | ||
1da177e4 LT |
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>" | |
43 | ||
1da177e4 LT |
44 | #include <linux/module.h> |
45 | #include <linux/errno.h> | |
46 | #include <linux/kernel.h> | |
47 | #include <linux/major.h> | |
48 | #include <linux/slab.h> | |
49 | #include <linux/poll.h> | |
50 | #include <linux/fcntl.h> | |
51 | #include <linux/init.h> | |
52 | #include <linux/skbuff.h> | |
53 | #include <linux/netdevice.h> | |
54 | #include <linux/etherdevice.h> | |
55 | #include <linux/miscdevice.h> | |
56 | #include <linux/ethtool.h> | |
57 | #include <linux/rtnetlink.h> | |
50857e2a | 58 | #include <linux/compat.h> |
1da177e4 LT |
59 | #include <linux/if.h> |
60 | #include <linux/if_arp.h> | |
61 | #include <linux/if_ether.h> | |
62 | #include <linux/if_tun.h> | |
6680ec68 | 63 | #include <linux/if_vlan.h> |
1da177e4 | 64 | #include <linux/crc32.h> |
d647a591 | 65 | #include <linux/nsproxy.h> |
f43798c2 | 66 | #include <linux/virtio_net.h> |
99405162 | 67 | #include <linux/rcupdate.h> |
881d966b | 68 | #include <net/net_namespace.h> |
79d17604 | 69 | #include <net/netns/generic.h> |
f019a7a5 | 70 | #include <net/rtnetlink.h> |
33dccbb0 | 71 | #include <net/sock.h> |
93e14b6d | 72 | #include <linux/seq_file.h> |
e0b46d0e | 73 | #include <linux/uio.h> |
1da177e4 | 74 | |
1da177e4 LT |
75 | #include <asm/uaccess.h> |
76 | ||
14daa021 RR |
77 | /* Uncomment to enable debugging */ |
78 | /* #define TUN_DEBUG 1 */ | |
79 | ||
1da177e4 LT |
80 | #ifdef TUN_DEBUG |
81 | static int debug; | |
14daa021 | 82 | |
6b8a66ee JP |
83 | #define tun_debug(level, tun, fmt, args...) \ |
84 | do { \ | |
85 | if (tun->debug) \ | |
86 | netdev_printk(level, tun->dev, fmt, ##args); \ | |
87 | } while (0) | |
88 | #define DBG1(level, fmt, args...) \ | |
89 | do { \ | |
90 | if (debug == 2) \ | |
91 | printk(level fmt, ##args); \ | |
92 | } while (0) | |
14daa021 | 93 | #else |
6b8a66ee JP |
94 | #define tun_debug(level, tun, fmt, args...) \ |
95 | do { \ | |
96 | if (0) \ | |
97 | netdev_printk(level, tun->dev, fmt, ##args); \ | |
98 | } while (0) | |
99 | #define DBG1(level, fmt, args...) \ | |
100 | do { \ | |
101 | if (0) \ | |
102 | printk(level fmt, ##args); \ | |
103 | } while (0) | |
14daa021 RR |
104 | #endif |
105 | ||
031f5e03 MT |
106 | /* TUN device flags */ |
107 | ||
108 | /* IFF_ATTACH_QUEUE is never stored in device flags, | |
109 | * overload it to mean fasync when stored there. | |
110 | */ | |
111 | #define TUN_FASYNC IFF_ATTACH_QUEUE | |
1cf8e410 MT |
112 | /* High bits in flags field are unused. */ |
113 | #define TUN_VNET_LE 0x80000000 | |
8b8e658b | 114 | #define TUN_VNET_BE 0x40000000 |
031f5e03 MT |
115 | |
116 | #define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \ | |
1cf8e410 | 117 | IFF_MULTI_QUEUE) |
0690899b MT |
118 | #define GOODCOPY_LEN 128 |
119 | ||
f271b2cc MK |
120 | #define FLT_EXACT_COUNT 8 |
121 | struct tap_filter { | |
122 | unsigned int count; /* Number of addrs. Zero means disabled */ | |
123 | u32 mask[2]; /* Mask of the hashed addrs */ | |
124 | unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN]; | |
125 | }; | |
126 | ||
baf71c5c PG |
127 | /* MAX_TAP_QUEUES 256 is chosen to allow rx/tx queues to be equal |
128 | * to max number of VCPUs in guest. */ | |
129 | #define MAX_TAP_QUEUES 256 | |
b8732fb7 | 130 | #define MAX_TAP_FLOWS 4096 |
c8d68e6b | 131 | |
96442e42 JW |
132 | #define TUN_FLOW_EXPIRE (3 * HZ) |
133 | ||
54f968d6 | 134 | /* A tun_file connects an open character device to a tuntap netdevice. It |
92d4ea6e | 135 | * also contains all socket related structures (except sock_fprog and tap_filter) |
54f968d6 JW |
136 | * to serve as one transmit queue for tuntap device. The sock_fprog and |
137 | * tap_filter were kept in tun_struct since they were used for filtering for the | |
36fe8c09 | 138 | * netdevice not for a specific queue (at least I didn't see the requirement for |
54f968d6 | 139 | * this). |
6e914fc7 JW |
140 | * |
141 | * RCU usage: | |
36fe8c09 | 142 | * The tun_file and tun_struct are loosely coupled, the pointer from one to the |
6e914fc7 | 143 | * other can only be read while rcu_read_lock or rtnl_lock is held. |
54f968d6 | 144 | */ |
631ab46b | 145 | struct tun_file { |
54f968d6 JW |
146 | struct sock sk; |
147 | struct socket socket; | |
148 | struct socket_wq wq; | |
6e914fc7 | 149 | struct tun_struct __rcu *tun; |
54f968d6 JW |
150 | struct fasync_struct *fasync; |
151 | /* only used for fasnyc */ | |
152 | unsigned int flags; | |
fb7589a1 PE |
153 | union { |
154 | u16 queue_index; | |
155 | unsigned int ifindex; | |
156 | }; | |
4008e97f JW |
157 | struct list_head next; |
158 | struct tun_struct *detached; | |
631ab46b EB |
159 | }; |
160 | ||
96442e42 JW |
161 | struct tun_flow_entry { |
162 | struct hlist_node hash_link; | |
163 | struct rcu_head rcu; | |
164 | struct tun_struct *tun; | |
165 | ||
166 | u32 rxhash; | |
9bc88939 | 167 | u32 rps_rxhash; |
96442e42 JW |
168 | int queue_index; |
169 | unsigned long updated; | |
170 | }; | |
171 | ||
172 | #define TUN_NUM_FLOW_ENTRIES 1024 | |
173 | ||
54f968d6 | 174 | /* Since the socket were moved to tun_file, to preserve the behavior of persist |
36fe8c09 | 175 | * device, socket filter, sndbuf and vnet header size were restore when the |
54f968d6 JW |
176 | * file were attached to a persist device. |
177 | */ | |
14daa021 | 178 | struct tun_struct { |
c8d68e6b JW |
179 | struct tun_file __rcu *tfiles[MAX_TAP_QUEUES]; |
180 | unsigned int numqueues; | |
f271b2cc | 181 | unsigned int flags; |
0625c883 EB |
182 | kuid_t owner; |
183 | kgid_t group; | |
14daa021 | 184 | |
14daa021 | 185 | struct net_device *dev; |
c8f44aff | 186 | netdev_features_t set_features; |
88255375 | 187 | #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \ |
e3e3c423 | 188 | NETIF_F_TSO6|NETIF_F_UFO) |
d9d52b51 | 189 | |
eaea34b2 | 190 | int align; |
d9d52b51 | 191 | int vnet_hdr_sz; |
54f968d6 JW |
192 | int sndbuf; |
193 | struct tap_filter txflt; | |
194 | struct sock_fprog fprog; | |
195 | /* protected by rtnl lock */ | |
196 | bool filter_attached; | |
14daa021 RR |
197 | #ifdef TUN_DEBUG |
198 | int debug; | |
1da177e4 | 199 | #endif |
96442e42 | 200 | spinlock_t lock; |
96442e42 JW |
201 | struct hlist_head flows[TUN_NUM_FLOW_ENTRIES]; |
202 | struct timer_list flow_gc_timer; | |
203 | unsigned long ageing_time; | |
4008e97f JW |
204 | unsigned int numdisabled; |
205 | struct list_head disabled; | |
5dbbaf2d | 206 | void *security; |
b8732fb7 | 207 | u32 flow_count; |
14daa021 | 208 | }; |
1da177e4 | 209 | |
8b8e658b GK |
210 | #ifdef CONFIG_TUN_VNET_CROSS_LE |
211 | static inline bool tun_legacy_is_little_endian(struct tun_struct *tun) | |
212 | { | |
213 | return tun->flags & TUN_VNET_BE ? false : | |
214 | virtio_legacy_is_little_endian(); | |
215 | } | |
216 | ||
217 | static long tun_get_vnet_be(struct tun_struct *tun, int __user *argp) | |
218 | { | |
219 | int be = !!(tun->flags & TUN_VNET_BE); | |
220 | ||
221 | if (put_user(be, argp)) | |
222 | return -EFAULT; | |
223 | ||
224 | return 0; | |
225 | } | |
226 | ||
227 | static long tun_set_vnet_be(struct tun_struct *tun, int __user *argp) | |
228 | { | |
229 | int be; | |
230 | ||
231 | if (get_user(be, argp)) | |
232 | return -EFAULT; | |
233 | ||
234 | if (be) | |
235 | tun->flags |= TUN_VNET_BE; | |
236 | else | |
237 | tun->flags &= ~TUN_VNET_BE; | |
238 | ||
239 | return 0; | |
240 | } | |
241 | #else | |
242 | static inline bool tun_legacy_is_little_endian(struct tun_struct *tun) | |
243 | { | |
244 | return virtio_legacy_is_little_endian(); | |
245 | } | |
246 | ||
247 | static long tun_get_vnet_be(struct tun_struct *tun, int __user *argp) | |
248 | { | |
249 | return -EINVAL; | |
250 | } | |
251 | ||
252 | static long tun_set_vnet_be(struct tun_struct *tun, int __user *argp) | |
253 | { | |
254 | return -EINVAL; | |
255 | } | |
256 | #endif /* CONFIG_TUN_VNET_CROSS_LE */ | |
257 | ||
25bd55bb GK |
258 | static inline bool tun_is_little_endian(struct tun_struct *tun) |
259 | { | |
7d824109 | 260 | return tun->flags & TUN_VNET_LE || |
8b8e658b | 261 | tun_legacy_is_little_endian(tun); |
25bd55bb GK |
262 | } |
263 | ||
56f0dcc5 MT |
264 | static inline u16 tun16_to_cpu(struct tun_struct *tun, __virtio16 val) |
265 | { | |
25bd55bb | 266 | return __virtio16_to_cpu(tun_is_little_endian(tun), val); |
56f0dcc5 MT |
267 | } |
268 | ||
269 | static inline __virtio16 cpu_to_tun16(struct tun_struct *tun, u16 val) | |
270 | { | |
25bd55bb | 271 | return __cpu_to_virtio16(tun_is_little_endian(tun), val); |
56f0dcc5 MT |
272 | } |
273 | ||
96442e42 JW |
274 | static inline u32 tun_hashfn(u32 rxhash) |
275 | { | |
276 | return rxhash & 0x3ff; | |
277 | } | |
278 | ||
279 | static struct tun_flow_entry *tun_flow_find(struct hlist_head *head, u32 rxhash) | |
280 | { | |
281 | struct tun_flow_entry *e; | |
96442e42 | 282 | |
b67bfe0d | 283 | hlist_for_each_entry_rcu(e, head, hash_link) { |
96442e42 JW |
284 | if (e->rxhash == rxhash) |
285 | return e; | |
286 | } | |
287 | return NULL; | |
288 | } | |
289 | ||
290 | static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun, | |
291 | struct hlist_head *head, | |
292 | u32 rxhash, u16 queue_index) | |
293 | { | |
9fdc6bef ED |
294 | struct tun_flow_entry *e = kmalloc(sizeof(*e), GFP_ATOMIC); |
295 | ||
96442e42 JW |
296 | if (e) { |
297 | tun_debug(KERN_INFO, tun, "create flow: hash %u index %u\n", | |
298 | rxhash, queue_index); | |
299 | e->updated = jiffies; | |
300 | e->rxhash = rxhash; | |
9bc88939 | 301 | e->rps_rxhash = 0; |
96442e42 JW |
302 | e->queue_index = queue_index; |
303 | e->tun = tun; | |
304 | hlist_add_head_rcu(&e->hash_link, head); | |
b8732fb7 | 305 | ++tun->flow_count; |
96442e42 JW |
306 | } |
307 | return e; | |
308 | } | |
309 | ||
96442e42 JW |
310 | static void tun_flow_delete(struct tun_struct *tun, struct tun_flow_entry *e) |
311 | { | |
312 | tun_debug(KERN_INFO, tun, "delete flow: hash %u index %u\n", | |
313 | e->rxhash, e->queue_index); | |
314 | hlist_del_rcu(&e->hash_link); | |
9fdc6bef | 315 | kfree_rcu(e, rcu); |
b8732fb7 | 316 | --tun->flow_count; |
96442e42 JW |
317 | } |
318 | ||
319 | static void tun_flow_flush(struct tun_struct *tun) | |
320 | { | |
321 | int i; | |
322 | ||
323 | spin_lock_bh(&tun->lock); | |
324 | for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { | |
325 | struct tun_flow_entry *e; | |
b67bfe0d | 326 | struct hlist_node *n; |
96442e42 | 327 | |
b67bfe0d | 328 | hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) |
96442e42 JW |
329 | tun_flow_delete(tun, e); |
330 | } | |
331 | spin_unlock_bh(&tun->lock); | |
332 | } | |
333 | ||
334 | static void tun_flow_delete_by_queue(struct tun_struct *tun, u16 queue_index) | |
335 | { | |
336 | int i; | |
337 | ||
338 | spin_lock_bh(&tun->lock); | |
339 | for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { | |
340 | struct tun_flow_entry *e; | |
b67bfe0d | 341 | struct hlist_node *n; |
96442e42 | 342 | |
b67bfe0d | 343 | hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) { |
96442e42 JW |
344 | if (e->queue_index == queue_index) |
345 | tun_flow_delete(tun, e); | |
346 | } | |
347 | } | |
348 | spin_unlock_bh(&tun->lock); | |
349 | } | |
350 | ||
351 | static void tun_flow_cleanup(unsigned long data) | |
352 | { | |
353 | struct tun_struct *tun = (struct tun_struct *)data; | |
354 | unsigned long delay = tun->ageing_time; | |
355 | unsigned long next_timer = jiffies + delay; | |
356 | unsigned long count = 0; | |
357 | int i; | |
358 | ||
359 | tun_debug(KERN_INFO, tun, "tun_flow_cleanup\n"); | |
360 | ||
361 | spin_lock_bh(&tun->lock); | |
362 | for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { | |
363 | struct tun_flow_entry *e; | |
b67bfe0d | 364 | struct hlist_node *n; |
96442e42 | 365 | |
b67bfe0d | 366 | hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) { |
96442e42 JW |
367 | unsigned long this_timer; |
368 | count++; | |
369 | this_timer = e->updated + delay; | |
370 | if (time_before_eq(this_timer, jiffies)) | |
371 | tun_flow_delete(tun, e); | |
372 | else if (time_before(this_timer, next_timer)) | |
373 | next_timer = this_timer; | |
374 | } | |
375 | } | |
376 | ||
377 | if (count) | |
378 | mod_timer(&tun->flow_gc_timer, round_jiffies_up(next_timer)); | |
379 | spin_unlock_bh(&tun->lock); | |
380 | } | |
381 | ||
49974420 | 382 | static void tun_flow_update(struct tun_struct *tun, u32 rxhash, |
9e85722d | 383 | struct tun_file *tfile) |
96442e42 JW |
384 | { |
385 | struct hlist_head *head; | |
386 | struct tun_flow_entry *e; | |
387 | unsigned long delay = tun->ageing_time; | |
9e85722d | 388 | u16 queue_index = tfile->queue_index; |
96442e42 JW |
389 | |
390 | if (!rxhash) | |
391 | return; | |
392 | else | |
393 | head = &tun->flows[tun_hashfn(rxhash)]; | |
394 | ||
395 | rcu_read_lock(); | |
396 | ||
9e85722d JW |
397 | /* We may get a very small possibility of OOO during switching, not |
398 | * worth to optimize.*/ | |
399 | if (tun->numqueues == 1 || tfile->detached) | |
96442e42 JW |
400 | goto unlock; |
401 | ||
402 | e = tun_flow_find(head, rxhash); | |
403 | if (likely(e)) { | |
404 | /* TODO: keep queueing to old queue until it's empty? */ | |
405 | e->queue_index = queue_index; | |
406 | e->updated = jiffies; | |
9bc88939 | 407 | sock_rps_record_flow_hash(e->rps_rxhash); |
96442e42 JW |
408 | } else { |
409 | spin_lock_bh(&tun->lock); | |
b8732fb7 JW |
410 | if (!tun_flow_find(head, rxhash) && |
411 | tun->flow_count < MAX_TAP_FLOWS) | |
96442e42 JW |
412 | tun_flow_create(tun, head, rxhash, queue_index); |
413 | ||
414 | if (!timer_pending(&tun->flow_gc_timer)) | |
415 | mod_timer(&tun->flow_gc_timer, | |
416 | round_jiffies_up(jiffies + delay)); | |
417 | spin_unlock_bh(&tun->lock); | |
418 | } | |
419 | ||
420 | unlock: | |
421 | rcu_read_unlock(); | |
422 | } | |
423 | ||
9bc88939 TH |
424 | /** |
425 | * Save the hash received in the stack receive path and update the | |
426 | * flow_hash table accordingly. | |
427 | */ | |
428 | static inline void tun_flow_save_rps_rxhash(struct tun_flow_entry *e, u32 hash) | |
429 | { | |
567e4b79 | 430 | if (unlikely(e->rps_rxhash != hash)) |
9bc88939 | 431 | e->rps_rxhash = hash; |
9bc88939 TH |
432 | } |
433 | ||
c8d68e6b | 434 | /* We try to identify a flow through its rxhash first. The reason that |
92d4ea6e | 435 | * we do not check rxq no. is because some cards(e.g 82599), chooses |
c8d68e6b JW |
436 | * the rxq based on the txq where the last packet of the flow comes. As |
437 | * the userspace application move between processors, we may get a | |
438 | * different rxq no. here. If we could not get rxhash, then we would | |
439 | * hope the rxq no. may help here. | |
440 | */ | |
f663dd9a | 441 | static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb, |
99932d4f | 442 | void *accel_priv, select_queue_fallback_t fallback) |
c8d68e6b JW |
443 | { |
444 | struct tun_struct *tun = netdev_priv(dev); | |
96442e42 | 445 | struct tun_flow_entry *e; |
c8d68e6b JW |
446 | u32 txq = 0; |
447 | u32 numqueues = 0; | |
448 | ||
449 | rcu_read_lock(); | |
92bb73ea | 450 | numqueues = ACCESS_ONCE(tun->numqueues); |
c8d68e6b | 451 | |
3958afa1 | 452 | txq = skb_get_hash(skb); |
c8d68e6b | 453 | if (txq) { |
96442e42 | 454 | e = tun_flow_find(&tun->flows[tun_hashfn(txq)], txq); |
9bc88939 | 455 | if (e) { |
9bc88939 | 456 | tun_flow_save_rps_rxhash(e, txq); |
fbe4d456 | 457 | txq = e->queue_index; |
9bc88939 | 458 | } else |
96442e42 JW |
459 | /* use multiply and shift instead of expensive divide */ |
460 | txq = ((u64)txq * numqueues) >> 32; | |
c8d68e6b JW |
461 | } else if (likely(skb_rx_queue_recorded(skb))) { |
462 | txq = skb_get_rx_queue(skb); | |
463 | while (unlikely(txq >= numqueues)) | |
464 | txq -= numqueues; | |
465 | } | |
466 | ||
467 | rcu_read_unlock(); | |
468 | return txq; | |
469 | } | |
470 | ||
cde8b15f JW |
471 | static inline bool tun_not_capable(struct tun_struct *tun) |
472 | { | |
473 | const struct cred *cred = current_cred(); | |
c260b772 | 474 | struct net *net = dev_net(tun->dev); |
cde8b15f JW |
475 | |
476 | return ((uid_valid(tun->owner) && !uid_eq(cred->euid, tun->owner)) || | |
477 | (gid_valid(tun->group) && !in_egroup_p(tun->group))) && | |
c260b772 | 478 | !ns_capable(net->user_ns, CAP_NET_ADMIN); |
cde8b15f JW |
479 | } |
480 | ||
c8d68e6b JW |
481 | static void tun_set_real_num_queues(struct tun_struct *tun) |
482 | { | |
483 | netif_set_real_num_tx_queues(tun->dev, tun->numqueues); | |
484 | netif_set_real_num_rx_queues(tun->dev, tun->numqueues); | |
485 | } | |
486 | ||
4008e97f JW |
487 | static void tun_disable_queue(struct tun_struct *tun, struct tun_file *tfile) |
488 | { | |
489 | tfile->detached = tun; | |
490 | list_add_tail(&tfile->next, &tun->disabled); | |
491 | ++tun->numdisabled; | |
492 | } | |
493 | ||
d32649d1 | 494 | static struct tun_struct *tun_enable_queue(struct tun_file *tfile) |
4008e97f JW |
495 | { |
496 | struct tun_struct *tun = tfile->detached; | |
497 | ||
498 | tfile->detached = NULL; | |
499 | list_del_init(&tfile->next); | |
500 | --tun->numdisabled; | |
501 | return tun; | |
502 | } | |
503 | ||
4bfb0513 JW |
504 | static void tun_queue_purge(struct tun_file *tfile) |
505 | { | |
506 | skb_queue_purge(&tfile->sk.sk_receive_queue); | |
507 | skb_queue_purge(&tfile->sk.sk_error_queue); | |
508 | } | |
509 | ||
c8d68e6b JW |
510 | static void __tun_detach(struct tun_file *tfile, bool clean) |
511 | { | |
512 | struct tun_file *ntfile; | |
513 | struct tun_struct *tun; | |
c8d68e6b | 514 | |
b8deabd3 JW |
515 | tun = rtnl_dereference(tfile->tun); |
516 | ||
9e85722d | 517 | if (tun && !tfile->detached) { |
c8d68e6b JW |
518 | u16 index = tfile->queue_index; |
519 | BUG_ON(index >= tun->numqueues); | |
c8d68e6b JW |
520 | |
521 | rcu_assign_pointer(tun->tfiles[index], | |
522 | tun->tfiles[tun->numqueues - 1]); | |
b8deabd3 | 523 | ntfile = rtnl_dereference(tun->tfiles[index]); |
c8d68e6b JW |
524 | ntfile->queue_index = index; |
525 | ||
526 | --tun->numqueues; | |
9e85722d | 527 | if (clean) { |
c956674b | 528 | RCU_INIT_POINTER(tfile->tun, NULL); |
4008e97f | 529 | sock_put(&tfile->sk); |
9e85722d | 530 | } else |
4008e97f | 531 | tun_disable_queue(tun, tfile); |
c8d68e6b JW |
532 | |
533 | synchronize_net(); | |
96442e42 | 534 | tun_flow_delete_by_queue(tun, tun->numqueues + 1); |
c8d68e6b | 535 | /* Drop read queue */ |
4bfb0513 | 536 | tun_queue_purge(tfile); |
c8d68e6b | 537 | tun_set_real_num_queues(tun); |
dd38bd85 | 538 | } else if (tfile->detached && clean) { |
4008e97f | 539 | tun = tun_enable_queue(tfile); |
dd38bd85 JW |
540 | sock_put(&tfile->sk); |
541 | } | |
c8d68e6b JW |
542 | |
543 | if (clean) { | |
af668b3c MT |
544 | if (tun && tun->numqueues == 0 && tun->numdisabled == 0) { |
545 | netif_carrier_off(tun->dev); | |
546 | ||
40630b82 | 547 | if (!(tun->flags & IFF_PERSIST) && |
af668b3c | 548 | tun->dev->reg_state == NETREG_REGISTERED) |
4008e97f | 549 | unregister_netdevice(tun->dev); |
af668b3c | 550 | } |
140e807d | 551 | sock_put(&tfile->sk); |
c8d68e6b JW |
552 | } |
553 | } | |
554 | ||
555 | static void tun_detach(struct tun_file *tfile, bool clean) | |
556 | { | |
557 | rtnl_lock(); | |
558 | __tun_detach(tfile, clean); | |
559 | rtnl_unlock(); | |
560 | } | |
561 | ||
562 | static void tun_detach_all(struct net_device *dev) | |
563 | { | |
564 | struct tun_struct *tun = netdev_priv(dev); | |
4008e97f | 565 | struct tun_file *tfile, *tmp; |
c8d68e6b JW |
566 | int i, n = tun->numqueues; |
567 | ||
568 | for (i = 0; i < n; i++) { | |
b8deabd3 | 569 | tfile = rtnl_dereference(tun->tfiles[i]); |
c8d68e6b | 570 | BUG_ON(!tfile); |
9e641bdc | 571 | tfile->socket.sk->sk_data_ready(tfile->socket.sk); |
c956674b | 572 | RCU_INIT_POINTER(tfile->tun, NULL); |
c8d68e6b JW |
573 | --tun->numqueues; |
574 | } | |
9e85722d | 575 | list_for_each_entry(tfile, &tun->disabled, next) { |
9e641bdc | 576 | tfile->socket.sk->sk_data_ready(tfile->socket.sk); |
c956674b | 577 | RCU_INIT_POINTER(tfile->tun, NULL); |
9e85722d | 578 | } |
c8d68e6b JW |
579 | BUG_ON(tun->numqueues != 0); |
580 | ||
581 | synchronize_net(); | |
582 | for (i = 0; i < n; i++) { | |
b8deabd3 | 583 | tfile = rtnl_dereference(tun->tfiles[i]); |
c8d68e6b | 584 | /* Drop read queue */ |
4bfb0513 | 585 | tun_queue_purge(tfile); |
c8d68e6b JW |
586 | sock_put(&tfile->sk); |
587 | } | |
4008e97f JW |
588 | list_for_each_entry_safe(tfile, tmp, &tun->disabled, next) { |
589 | tun_enable_queue(tfile); | |
4bfb0513 | 590 | tun_queue_purge(tfile); |
4008e97f JW |
591 | sock_put(&tfile->sk); |
592 | } | |
593 | BUG_ON(tun->numdisabled != 0); | |
dd38bd85 | 594 | |
40630b82 | 595 | if (tun->flags & IFF_PERSIST) |
dd38bd85 | 596 | module_put(THIS_MODULE); |
c8d68e6b JW |
597 | } |
598 | ||
849c9b6f | 599 | static int tun_attach(struct tun_struct *tun, struct file *file, bool skip_filter) |
a7385ba2 | 600 | { |
631ab46b | 601 | struct tun_file *tfile = file->private_data; |
38231b7a | 602 | int err; |
a7385ba2 | 603 | |
5dbbaf2d PM |
604 | err = security_tun_dev_attach(tfile->socket.sk, tun->security); |
605 | if (err < 0) | |
606 | goto out; | |
607 | ||
38231b7a | 608 | err = -EINVAL; |
9e85722d | 609 | if (rtnl_dereference(tfile->tun) && !tfile->detached) |
38231b7a EB |
610 | goto out; |
611 | ||
612 | err = -EBUSY; | |
40630b82 | 613 | if (!(tun->flags & IFF_MULTI_QUEUE) && tun->numqueues == 1) |
c8d68e6b JW |
614 | goto out; |
615 | ||
616 | err = -E2BIG; | |
4008e97f JW |
617 | if (!tfile->detached && |
618 | tun->numqueues + tun->numdisabled == MAX_TAP_QUEUES) | |
38231b7a EB |
619 | goto out; |
620 | ||
621 | err = 0; | |
54f968d6 | 622 | |
92d4ea6e | 623 | /* Re-attach the filter to persist device */ |
849c9b6f | 624 | if (!skip_filter && (tun->filter_attached == true)) { |
5a5abb1f DB |
625 | err = __sk_attach_filter(&tun->fprog, tfile->socket.sk, |
626 | lockdep_rtnl_is_held()); | |
54f968d6 JW |
627 | if (!err) |
628 | goto out; | |
629 | } | |
c8d68e6b | 630 | tfile->queue_index = tun->numqueues; |
6e914fc7 | 631 | rcu_assign_pointer(tfile->tun, tun); |
c8d68e6b | 632 | rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile); |
c8d68e6b | 633 | tun->numqueues++; |
a7385ba2 | 634 | |
4008e97f JW |
635 | if (tfile->detached) |
636 | tun_enable_queue(tfile); | |
637 | else | |
638 | sock_hold(&tfile->sk); | |
639 | ||
c8d68e6b | 640 | tun_set_real_num_queues(tun); |
a7385ba2 | 641 | |
c8d68e6b JW |
642 | /* device is allowed to go away first, so no need to hold extra |
643 | * refcnt. | |
644 | */ | |
645 | ||
646 | out: | |
647 | return err; | |
631ab46b EB |
648 | } |
649 | ||
650 | static struct tun_struct *__tun_get(struct tun_file *tfile) | |
651 | { | |
6e914fc7 | 652 | struct tun_struct *tun; |
c70f1829 | 653 | |
6e914fc7 JW |
654 | rcu_read_lock(); |
655 | tun = rcu_dereference(tfile->tun); | |
656 | if (tun) | |
657 | dev_hold(tun->dev); | |
658 | rcu_read_unlock(); | |
c70f1829 EB |
659 | |
660 | return tun; | |
631ab46b EB |
661 | } |
662 | ||
663 | static struct tun_struct *tun_get(struct file *file) | |
664 | { | |
665 | return __tun_get(file->private_data); | |
666 | } | |
667 | ||
668 | static void tun_put(struct tun_struct *tun) | |
669 | { | |
6e914fc7 | 670 | dev_put(tun->dev); |
631ab46b EB |
671 | } |
672 | ||
6b8a66ee | 673 | /* TAP filtering */ |
f271b2cc MK |
674 | static void addr_hash_set(u32 *mask, const u8 *addr) |
675 | { | |
676 | int n = ether_crc(ETH_ALEN, addr) >> 26; | |
677 | mask[n >> 5] |= (1 << (n & 31)); | |
678 | } | |
679 | ||
680 | static unsigned int addr_hash_test(const u32 *mask, const u8 *addr) | |
681 | { | |
682 | int n = ether_crc(ETH_ALEN, addr) >> 26; | |
683 | return mask[n >> 5] & (1 << (n & 31)); | |
684 | } | |
685 | ||
686 | static int update_filter(struct tap_filter *filter, void __user *arg) | |
687 | { | |
688 | struct { u8 u[ETH_ALEN]; } *addr; | |
689 | struct tun_filter uf; | |
690 | int err, alen, n, nexact; | |
691 | ||
692 | if (copy_from_user(&uf, arg, sizeof(uf))) | |
693 | return -EFAULT; | |
694 | ||
695 | if (!uf.count) { | |
696 | /* Disabled */ | |
697 | filter->count = 0; | |
698 | return 0; | |
699 | } | |
700 | ||
701 | alen = ETH_ALEN * uf.count; | |
702 | addr = kmalloc(alen, GFP_KERNEL); | |
703 | if (!addr) | |
704 | return -ENOMEM; | |
705 | ||
706 | if (copy_from_user(addr, arg + sizeof(uf), alen)) { | |
707 | err = -EFAULT; | |
708 | goto done; | |
709 | } | |
710 | ||
711 | /* The filter is updated without holding any locks. Which is | |
712 | * perfectly safe. We disable it first and in the worst | |
713 | * case we'll accept a few undesired packets. */ | |
714 | filter->count = 0; | |
715 | wmb(); | |
716 | ||
717 | /* Use first set of addresses as an exact filter */ | |
718 | for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++) | |
719 | memcpy(filter->addr[n], addr[n].u, ETH_ALEN); | |
720 | ||
721 | nexact = n; | |
722 | ||
cfbf84fc AW |
723 | /* Remaining multicast addresses are hashed, |
724 | * unicast will leave the filter disabled. */ | |
f271b2cc | 725 | memset(filter->mask, 0, sizeof(filter->mask)); |
cfbf84fc AW |
726 | for (; n < uf.count; n++) { |
727 | if (!is_multicast_ether_addr(addr[n].u)) { | |
728 | err = 0; /* no filter */ | |
729 | goto done; | |
730 | } | |
f271b2cc | 731 | addr_hash_set(filter->mask, addr[n].u); |
cfbf84fc | 732 | } |
f271b2cc MK |
733 | |
734 | /* For ALLMULTI just set the mask to all ones. | |
735 | * This overrides the mask populated above. */ | |
736 | if ((uf.flags & TUN_FLT_ALLMULTI)) | |
737 | memset(filter->mask, ~0, sizeof(filter->mask)); | |
738 | ||
739 | /* Now enable the filter */ | |
740 | wmb(); | |
741 | filter->count = nexact; | |
742 | ||
743 | /* Return the number of exact filters */ | |
744 | err = nexact; | |
745 | ||
746 | done: | |
747 | kfree(addr); | |
748 | return err; | |
749 | } | |
750 | ||
751 | /* Returns: 0 - drop, !=0 - accept */ | |
752 | static int run_filter(struct tap_filter *filter, const struct sk_buff *skb) | |
753 | { | |
754 | /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect | |
755 | * at this point. */ | |
756 | struct ethhdr *eh = (struct ethhdr *) skb->data; | |
757 | int i; | |
758 | ||
759 | /* Exact match */ | |
760 | for (i = 0; i < filter->count; i++) | |
2e42e474 | 761 | if (ether_addr_equal(eh->h_dest, filter->addr[i])) |
f271b2cc MK |
762 | return 1; |
763 | ||
764 | /* Inexact match (multicast only) */ | |
765 | if (is_multicast_ether_addr(eh->h_dest)) | |
766 | return addr_hash_test(filter->mask, eh->h_dest); | |
767 | ||
768 | return 0; | |
769 | } | |
770 | ||
771 | /* | |
772 | * Checks whether the packet is accepted or not. | |
773 | * Returns: 0 - drop, !=0 - accept | |
774 | */ | |
775 | static int check_filter(struct tap_filter *filter, const struct sk_buff *skb) | |
776 | { | |
777 | if (!filter->count) | |
778 | return 1; | |
779 | ||
780 | return run_filter(filter, skb); | |
781 | } | |
782 | ||
1da177e4 LT |
783 | /* Network device part of the driver */ |
784 | ||
7282d491 | 785 | static const struct ethtool_ops tun_ethtool_ops; |
1da177e4 | 786 | |
c70f1829 EB |
787 | /* Net device detach from fd. */ |
788 | static void tun_net_uninit(struct net_device *dev) | |
789 | { | |
c8d68e6b | 790 | tun_detach_all(dev); |
c70f1829 EB |
791 | } |
792 | ||
1da177e4 LT |
793 | /* Net device open. */ |
794 | static int tun_net_open(struct net_device *dev) | |
795 | { | |
c8d68e6b | 796 | netif_tx_start_all_queues(dev); |
1da177e4 LT |
797 | return 0; |
798 | } | |
799 | ||
800 | /* Net device close. */ | |
801 | static int tun_net_close(struct net_device *dev) | |
802 | { | |
c8d68e6b | 803 | netif_tx_stop_all_queues(dev); |
1da177e4 LT |
804 | return 0; |
805 | } | |
806 | ||
807 | /* Net device start xmit */ | |
424efe9c | 808 | static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) |
1da177e4 LT |
809 | { |
810 | struct tun_struct *tun = netdev_priv(dev); | |
c8d68e6b | 811 | int txq = skb->queue_mapping; |
6e914fc7 | 812 | struct tun_file *tfile; |
fa35864e | 813 | u32 numqueues = 0; |
1da177e4 | 814 | |
6e914fc7 | 815 | rcu_read_lock(); |
c8d68e6b | 816 | tfile = rcu_dereference(tun->tfiles[txq]); |
fa35864e | 817 | numqueues = ACCESS_ONCE(tun->numqueues); |
c8d68e6b | 818 | |
1da177e4 | 819 | /* Drop packet if interface is not attached */ |
fa35864e | 820 | if (txq >= numqueues) |
1da177e4 LT |
821 | goto drop; |
822 | ||
fa35864e | 823 | if (numqueues == 1) { |
9bc88939 TH |
824 | /* Select queue was not called for the skbuff, so we extract the |
825 | * RPS hash and save it into the flow_table here. | |
826 | */ | |
827 | __u32 rxhash; | |
828 | ||
829 | rxhash = skb_get_hash(skb); | |
830 | if (rxhash) { | |
831 | struct tun_flow_entry *e; | |
832 | e = tun_flow_find(&tun->flows[tun_hashfn(rxhash)], | |
833 | rxhash); | |
834 | if (e) | |
835 | tun_flow_save_rps_rxhash(e, rxhash); | |
836 | } | |
837 | } | |
838 | ||
6e914fc7 JW |
839 | tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len); |
840 | ||
c8d68e6b JW |
841 | BUG_ON(!tfile); |
842 | ||
f271b2cc MK |
843 | /* Drop if the filter does not like it. |
844 | * This is a noop if the filter is disabled. | |
845 | * Filter can be enabled only for the TAP devices. */ | |
846 | if (!check_filter(&tun->txflt, skb)) | |
847 | goto drop; | |
848 | ||
54f968d6 JW |
849 | if (tfile->socket.sk->sk_filter && |
850 | sk_filter(tfile->socket.sk, skb)) | |
99405162 MT |
851 | goto drop; |
852 | ||
36fe8c09 | 853 | /* Limit the number of packets queued by dividing txq length with the |
c8d68e6b JW |
854 | * number of queues. |
855 | */ | |
fa35864e DC |
856 | if (skb_queue_len(&tfile->socket.sk->sk_receive_queue) * numqueues |
857 | >= dev->tx_queue_len) | |
5d097109 | 858 | goto drop; |
1da177e4 | 859 | |
7bf66305 JW |
860 | if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC))) |
861 | goto drop; | |
862 | ||
5fcd2d8b | 863 | if (skb->sk && sk_fullsock(skb->sk)) { |
c14ac945 SHY |
864 | sock_tx_timestamp(skb->sk, skb->sk->sk_tsflags, |
865 | &skb_shinfo(skb)->tx_flags); | |
eda29772 RC |
866 | sw_tx_timestamp(skb); |
867 | } | |
868 | ||
0110d6f2 | 869 | /* Orphan the skb - required as we might hang on to it |
7bf66305 JW |
870 | * for indefinite time. |
871 | */ | |
0110d6f2 MT |
872 | skb_orphan(skb); |
873 | ||
f8af75f3 ED |
874 | nf_reset(skb); |
875 | ||
f271b2cc | 876 | /* Enqueue packet */ |
54f968d6 | 877 | skb_queue_tail(&tfile->socket.sk->sk_receive_queue, skb); |
1da177e4 LT |
878 | |
879 | /* Notify and wake up reader process */ | |
54f968d6 JW |
880 | if (tfile->flags & TUN_FASYNC) |
881 | kill_fasync(&tfile->fasync, SIGIO, POLL_IN); | |
9e641bdc | 882 | tfile->socket.sk->sk_data_ready(tfile->socket.sk); |
6e914fc7 JW |
883 | |
884 | rcu_read_unlock(); | |
6ed10654 | 885 | return NETDEV_TX_OK; |
1da177e4 LT |
886 | |
887 | drop: | |
09f75cd7 | 888 | dev->stats.tx_dropped++; |
149d36f7 | 889 | skb_tx_error(skb); |
1da177e4 | 890 | kfree_skb(skb); |
6e914fc7 | 891 | rcu_read_unlock(); |
baeababb | 892 | return NET_XMIT_DROP; |
1da177e4 LT |
893 | } |
894 | ||
f271b2cc | 895 | static void tun_net_mclist(struct net_device *dev) |
1da177e4 | 896 | { |
f271b2cc MK |
897 | /* |
898 | * This callback is supposed to deal with mc filter in | |
899 | * _rx_ path and has nothing to do with the _tx_ path. | |
900 | * In rx path we always accept everything userspace gives us. | |
901 | */ | |
1da177e4 LT |
902 | } |
903 | ||
4885a504 ES |
904 | #define MIN_MTU 68 |
905 | #define MAX_MTU 65535 | |
906 | ||
907 | static int | |
908 | tun_net_change_mtu(struct net_device *dev, int new_mtu) | |
909 | { | |
910 | if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU) | |
911 | return -EINVAL; | |
912 | dev->mtu = new_mtu; | |
913 | return 0; | |
914 | } | |
915 | ||
c8f44aff MM |
916 | static netdev_features_t tun_net_fix_features(struct net_device *dev, |
917 | netdev_features_t features) | |
88255375 MM |
918 | { |
919 | struct tun_struct *tun = netdev_priv(dev); | |
920 | ||
921 | return (features & tun->set_features) | (features & ~TUN_USER_FEATURES); | |
922 | } | |
bebd097a NH |
923 | #ifdef CONFIG_NET_POLL_CONTROLLER |
924 | static void tun_poll_controller(struct net_device *dev) | |
925 | { | |
926 | /* | |
927 | * Tun only receives frames when: | |
928 | * 1) the char device endpoint gets data from user space | |
929 | * 2) the tun socket gets a sendmsg call from user space | |
92d4ea6e | 930 | * Since both of those are synchronous operations, we are guaranteed |
bebd097a | 931 | * never to have pending data when we poll for it |
92d4ea6e | 932 | * so there is nothing to do here but return. |
bebd097a NH |
933 | * We need this though so netpoll recognizes us as an interface that |
934 | * supports polling, which enables bridge devices in virt setups to | |
935 | * still use netconsole | |
936 | */ | |
937 | return; | |
938 | } | |
939 | #endif | |
eaea34b2 PA |
940 | |
941 | static void tun_set_headroom(struct net_device *dev, int new_hr) | |
942 | { | |
943 | struct tun_struct *tun = netdev_priv(dev); | |
944 | ||
945 | if (new_hr < NET_SKB_PAD) | |
946 | new_hr = NET_SKB_PAD; | |
947 | ||
948 | tun->align = new_hr; | |
949 | } | |
950 | ||
758e43b7 | 951 | static const struct net_device_ops tun_netdev_ops = { |
c70f1829 | 952 | .ndo_uninit = tun_net_uninit, |
758e43b7 SH |
953 | .ndo_open = tun_net_open, |
954 | .ndo_stop = tun_net_close, | |
00829823 | 955 | .ndo_start_xmit = tun_net_xmit, |
758e43b7 | 956 | .ndo_change_mtu = tun_net_change_mtu, |
88255375 | 957 | .ndo_fix_features = tun_net_fix_features, |
c8d68e6b | 958 | .ndo_select_queue = tun_select_queue, |
bebd097a NH |
959 | #ifdef CONFIG_NET_POLL_CONTROLLER |
960 | .ndo_poll_controller = tun_poll_controller, | |
961 | #endif | |
eaea34b2 | 962 | .ndo_set_rx_headroom = tun_set_headroom, |
758e43b7 SH |
963 | }; |
964 | ||
965 | static const struct net_device_ops tap_netdev_ops = { | |
c70f1829 | 966 | .ndo_uninit = tun_net_uninit, |
758e43b7 SH |
967 | .ndo_open = tun_net_open, |
968 | .ndo_stop = tun_net_close, | |
00829823 | 969 | .ndo_start_xmit = tun_net_xmit, |
758e43b7 | 970 | .ndo_change_mtu = tun_net_change_mtu, |
88255375 | 971 | .ndo_fix_features = tun_net_fix_features, |
afc4b13d | 972 | .ndo_set_rx_mode = tun_net_mclist, |
758e43b7 SH |
973 | .ndo_set_mac_address = eth_mac_addr, |
974 | .ndo_validate_addr = eth_validate_addr, | |
c8d68e6b | 975 | .ndo_select_queue = tun_select_queue, |
bebd097a NH |
976 | #ifdef CONFIG_NET_POLL_CONTROLLER |
977 | .ndo_poll_controller = tun_poll_controller, | |
978 | #endif | |
5e52796a | 979 | .ndo_features_check = passthru_features_check, |
eaea34b2 | 980 | .ndo_set_rx_headroom = tun_set_headroom, |
758e43b7 SH |
981 | }; |
982 | ||
944a1376 | 983 | static void tun_flow_init(struct tun_struct *tun) |
96442e42 JW |
984 | { |
985 | int i; | |
986 | ||
96442e42 JW |
987 | for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) |
988 | INIT_HLIST_HEAD(&tun->flows[i]); | |
989 | ||
990 | tun->ageing_time = TUN_FLOW_EXPIRE; | |
991 | setup_timer(&tun->flow_gc_timer, tun_flow_cleanup, (unsigned long)tun); | |
992 | mod_timer(&tun->flow_gc_timer, | |
993 | round_jiffies_up(jiffies + tun->ageing_time)); | |
96442e42 JW |
994 | } |
995 | ||
996 | static void tun_flow_uninit(struct tun_struct *tun) | |
997 | { | |
998 | del_timer_sync(&tun->flow_gc_timer); | |
999 | tun_flow_flush(tun); | |
96442e42 JW |
1000 | } |
1001 | ||
1da177e4 LT |
1002 | /* Initialize net device. */ |
1003 | static void tun_net_init(struct net_device *dev) | |
1004 | { | |
1005 | struct tun_struct *tun = netdev_priv(dev); | |
6aa20a22 | 1006 | |
1da177e4 | 1007 | switch (tun->flags & TUN_TYPE_MASK) { |
40630b82 | 1008 | case IFF_TUN: |
758e43b7 SH |
1009 | dev->netdev_ops = &tun_netdev_ops; |
1010 | ||
1da177e4 LT |
1011 | /* Point-to-Point TUN Device */ |
1012 | dev->hard_header_len = 0; | |
1013 | dev->addr_len = 0; | |
1014 | dev->mtu = 1500; | |
1015 | ||
1016 | /* Zero header length */ | |
6aa20a22 | 1017 | dev->type = ARPHRD_NONE; |
1da177e4 LT |
1018 | dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; |
1019 | dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ | |
1020 | break; | |
1021 | ||
40630b82 | 1022 | case IFF_TAP: |
7a0a9608 | 1023 | dev->netdev_ops = &tap_netdev_ops; |
1da177e4 | 1024 | /* Ethernet TAP Device */ |
1da177e4 | 1025 | ether_setup(dev); |
550fd08c | 1026 | dev->priv_flags &= ~IFF_TX_SKB_SHARING; |
a676847b | 1027 | dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; |
36226a8d | 1028 | |
f2cedb63 | 1029 | eth_hw_addr_random(dev); |
36226a8d | 1030 | |
1da177e4 LT |
1031 | dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ |
1032 | break; | |
1033 | } | |
1034 | } | |
1035 | ||
1036 | /* Character device part */ | |
1037 | ||
1038 | /* Poll */ | |
c8d68e6b | 1039 | static unsigned int tun_chr_poll(struct file *file, poll_table *wait) |
6aa20a22 | 1040 | { |
b2430de3 EB |
1041 | struct tun_file *tfile = file->private_data; |
1042 | struct tun_struct *tun = __tun_get(tfile); | |
3c8a9c63 | 1043 | struct sock *sk; |
33dccbb0 | 1044 | unsigned int mask = 0; |
1da177e4 LT |
1045 | |
1046 | if (!tun) | |
eac9e902 | 1047 | return POLLERR; |
1da177e4 | 1048 | |
54f968d6 | 1049 | sk = tfile->socket.sk; |
3c8a9c63 | 1050 | |
6b8a66ee | 1051 | tun_debug(KERN_INFO, tun, "tun_chr_poll\n"); |
1da177e4 | 1052 | |
9e641bdc | 1053 | poll_wait(file, sk_sleep(sk), wait); |
6aa20a22 | 1054 | |
89f56d1e | 1055 | if (!skb_queue_empty(&sk->sk_receive_queue)) |
1da177e4 LT |
1056 | mask |= POLLIN | POLLRDNORM; |
1057 | ||
33dccbb0 | 1058 | if (sock_writeable(sk) || |
9cd3e072 | 1059 | (!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags) && |
33dccbb0 HX |
1060 | sock_writeable(sk))) |
1061 | mask |= POLLOUT | POLLWRNORM; | |
1062 | ||
c70f1829 EB |
1063 | if (tun->dev->reg_state != NETREG_REGISTERED) |
1064 | mask = POLLERR; | |
1065 | ||
631ab46b | 1066 | tun_put(tun); |
1da177e4 LT |
1067 | return mask; |
1068 | } | |
1069 | ||
f42157cb RR |
1070 | /* prepad is the amount to reserve at front. len is length after that. |
1071 | * linear is a hint as to how much to copy (usually headers). */ | |
54f968d6 | 1072 | static struct sk_buff *tun_alloc_skb(struct tun_file *tfile, |
6f7c156c | 1073 | size_t prepad, size_t len, |
1074 | size_t linear, int noblock) | |
f42157cb | 1075 | { |
54f968d6 | 1076 | struct sock *sk = tfile->socket.sk; |
f42157cb | 1077 | struct sk_buff *skb; |
33dccbb0 | 1078 | int err; |
f42157cb RR |
1079 | |
1080 | /* Under a page? Don't bother with paged skb. */ | |
0eca93bc | 1081 | if (prepad + len < PAGE_SIZE || !linear) |
33dccbb0 | 1082 | linear = len; |
f42157cb | 1083 | |
33dccbb0 | 1084 | skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, |
28d64271 | 1085 | &err, 0); |
f42157cb | 1086 | if (!skb) |
33dccbb0 | 1087 | return ERR_PTR(err); |
f42157cb RR |
1088 | |
1089 | skb_reserve(skb, prepad); | |
1090 | skb_put(skb, linear); | |
33dccbb0 HX |
1091 | skb->data_len = len - linear; |
1092 | skb->len += len - linear; | |
f42157cb RR |
1093 | |
1094 | return skb; | |
1095 | } | |
1096 | ||
1da177e4 | 1097 | /* Get packet from user space buffer */ |
54f968d6 | 1098 | static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, |
f5ff53b4 AV |
1099 | void *msg_control, struct iov_iter *from, |
1100 | int noblock) | |
1da177e4 | 1101 | { |
09640e63 | 1102 | struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) }; |
1da177e4 | 1103 | struct sk_buff *skb; |
f5ff53b4 | 1104 | size_t total_len = iov_iter_count(from); |
eaea34b2 | 1105 | size_t len = total_len, align = tun->align, linear; |
f43798c2 | 1106 | struct virtio_net_hdr gso = { 0 }; |
96f8d9ec | 1107 | int good_linear; |
0690899b MT |
1108 | int copylen; |
1109 | bool zerocopy = false; | |
1110 | int err; | |
49974420 | 1111 | u32 rxhash; |
f5ff53b4 | 1112 | ssize_t n; |
1da177e4 | 1113 | |
1bd4978a ED |
1114 | if (!(tun->dev->flags & IFF_UP)) |
1115 | return -EIO; | |
1116 | ||
40630b82 | 1117 | if (!(tun->flags & IFF_NO_PI)) { |
15718ea0 | 1118 | if (len < sizeof(pi)) |
1da177e4 | 1119 | return -EINVAL; |
15718ea0 | 1120 | len -= sizeof(pi); |
1da177e4 | 1121 | |
f5ff53b4 AV |
1122 | n = copy_from_iter(&pi, sizeof(pi), from); |
1123 | if (n != sizeof(pi)) | |
1da177e4 LT |
1124 | return -EFAULT; |
1125 | } | |
1126 | ||
40630b82 | 1127 | if (tun->flags & IFF_VNET_HDR) { |
15718ea0 | 1128 | if (len < tun->vnet_hdr_sz) |
f43798c2 | 1129 | return -EINVAL; |
15718ea0 | 1130 | len -= tun->vnet_hdr_sz; |
f43798c2 | 1131 | |
f5ff53b4 AV |
1132 | n = copy_from_iter(&gso, sizeof(gso), from); |
1133 | if (n != sizeof(gso)) | |
f43798c2 RR |
1134 | return -EFAULT; |
1135 | ||
4909122f | 1136 | if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && |
56f0dcc5 MT |
1137 | tun16_to_cpu(tun, gso.csum_start) + tun16_to_cpu(tun, gso.csum_offset) + 2 > tun16_to_cpu(tun, gso.hdr_len)) |
1138 | gso.hdr_len = cpu_to_tun16(tun, tun16_to_cpu(tun, gso.csum_start) + tun16_to_cpu(tun, gso.csum_offset) + 2); | |
4909122f | 1139 | |
56f0dcc5 | 1140 | if (tun16_to_cpu(tun, gso.hdr_len) > len) |
f43798c2 | 1141 | return -EINVAL; |
d8febb77 | 1142 | iov_iter_advance(from, tun->vnet_hdr_sz - sizeof(gso)); |
f43798c2 RR |
1143 | } |
1144 | ||
40630b82 | 1145 | if ((tun->flags & TUN_TYPE_MASK) == IFF_TAP) { |
a504b86e | 1146 | align += NET_IP_ALIGN; |
0eca93bc | 1147 | if (unlikely(len < ETH_HLEN || |
56f0dcc5 | 1148 | (gso.hdr_len && tun16_to_cpu(tun, gso.hdr_len) < ETH_HLEN))) |
e01bf1c8 RR |
1149 | return -EINVAL; |
1150 | } | |
6aa20a22 | 1151 | |
96f8d9ec JW |
1152 | good_linear = SKB_MAX_HEAD(align); |
1153 | ||
88529176 | 1154 | if (msg_control) { |
f5ff53b4 AV |
1155 | struct iov_iter i = *from; |
1156 | ||
88529176 JW |
1157 | /* There are 256 bytes to be copied in skb, so there is |
1158 | * enough room for skb expand head in case it is used. | |
0690899b MT |
1159 | * The rest of the buffer is mapped from userspace. |
1160 | */ | |
56f0dcc5 | 1161 | copylen = gso.hdr_len ? tun16_to_cpu(tun, gso.hdr_len) : GOODCOPY_LEN; |
96f8d9ec JW |
1162 | if (copylen > good_linear) |
1163 | copylen = good_linear; | |
3dd5c330 | 1164 | linear = copylen; |
f5ff53b4 AV |
1165 | iov_iter_advance(&i, copylen); |
1166 | if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS) | |
88529176 JW |
1167 | zerocopy = true; |
1168 | } | |
1169 | ||
1170 | if (!zerocopy) { | |
0690899b | 1171 | copylen = len; |
56f0dcc5 | 1172 | if (tun16_to_cpu(tun, gso.hdr_len) > good_linear) |
96f8d9ec JW |
1173 | linear = good_linear; |
1174 | else | |
56f0dcc5 | 1175 | linear = tun16_to_cpu(tun, gso.hdr_len); |
3dd5c330 | 1176 | } |
0690899b | 1177 | |
3dd5c330 | 1178 | skb = tun_alloc_skb(tfile, align, copylen, linear, noblock); |
33dccbb0 HX |
1179 | if (IS_ERR(skb)) { |
1180 | if (PTR_ERR(skb) != -EAGAIN) | |
1181 | tun->dev->stats.rx_dropped++; | |
1182 | return PTR_ERR(skb); | |
1da177e4 LT |
1183 | } |
1184 | ||
0690899b | 1185 | if (zerocopy) |
f5ff53b4 | 1186 | err = zerocopy_sg_from_iter(skb, from); |
88529176 | 1187 | else { |
f5ff53b4 | 1188 | err = skb_copy_datagram_from_iter(skb, 0, from, len); |
88529176 JW |
1189 | if (!err && msg_control) { |
1190 | struct ubuf_info *uarg = msg_control; | |
1191 | uarg->callback(uarg, false); | |
1192 | } | |
1193 | } | |
0690899b MT |
1194 | |
1195 | if (err) { | |
09f75cd7 | 1196 | tun->dev->stats.rx_dropped++; |
8f22757e | 1197 | kfree_skb(skb); |
1da177e4 | 1198 | return -EFAULT; |
8f22757e | 1199 | } |
1da177e4 | 1200 | |
f43798c2 | 1201 | if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { |
56f0dcc5 MT |
1202 | if (!skb_partial_csum_set(skb, tun16_to_cpu(tun, gso.csum_start), |
1203 | tun16_to_cpu(tun, gso.csum_offset))) { | |
f43798c2 RR |
1204 | tun->dev->stats.rx_frame_errors++; |
1205 | kfree_skb(skb); | |
1206 | return -EINVAL; | |
1207 | } | |
88255375 | 1208 | } |
f43798c2 | 1209 | |
1da177e4 | 1210 | switch (tun->flags & TUN_TYPE_MASK) { |
40630b82 MT |
1211 | case IFF_TUN: |
1212 | if (tun->flags & IFF_NO_PI) { | |
f09f7ee2 AWC |
1213 | switch (skb->data[0] & 0xf0) { |
1214 | case 0x40: | |
1215 | pi.proto = htons(ETH_P_IP); | |
1216 | break; | |
1217 | case 0x60: | |
1218 | pi.proto = htons(ETH_P_IPV6); | |
1219 | break; | |
1220 | default: | |
1221 | tun->dev->stats.rx_dropped++; | |
1222 | kfree_skb(skb); | |
1223 | return -EINVAL; | |
1224 | } | |
1225 | } | |
1226 | ||
459a98ed | 1227 | skb_reset_mac_header(skb); |
1da177e4 | 1228 | skb->protocol = pi.proto; |
4c13eb66 | 1229 | skb->dev = tun->dev; |
1da177e4 | 1230 | break; |
40630b82 | 1231 | case IFF_TAP: |
1da177e4 LT |
1232 | skb->protocol = eth_type_trans(skb, tun->dev); |
1233 | break; | |
6403eab1 | 1234 | } |
1da177e4 | 1235 | |
f43798c2 RR |
1236 | if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) { |
1237 | pr_debug("GSO!\n"); | |
1238 | switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { | |
1239 | case VIRTIO_NET_HDR_GSO_TCPV4: | |
c9af6db4 | 1240 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; |
f43798c2 RR |
1241 | break; |
1242 | case VIRTIO_NET_HDR_GSO_TCPV6: | |
c9af6db4 | 1243 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; |
f43798c2 | 1244 | break; |
e36aa25a | 1245 | case VIRTIO_NET_HDR_GSO_UDP: |
c9af6db4 | 1246 | skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
e36aa25a | 1247 | break; |
f43798c2 RR |
1248 | default: |
1249 | tun->dev->stats.rx_frame_errors++; | |
1250 | kfree_skb(skb); | |
1251 | return -EINVAL; | |
1252 | } | |
1253 | ||
1254 | if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN) | |
c9af6db4 | 1255 | skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; |
f43798c2 | 1256 | |
56f0dcc5 | 1257 | skb_shinfo(skb)->gso_size = tun16_to_cpu(tun, gso.gso_size); |
f43798c2 RR |
1258 | if (skb_shinfo(skb)->gso_size == 0) { |
1259 | tun->dev->stats.rx_frame_errors++; | |
1260 | kfree_skb(skb); | |
1261 | return -EINVAL; | |
1262 | } | |
1263 | ||
1264 | /* Header must be checked, and gso_segs computed. */ | |
1265 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; | |
1266 | skb_shinfo(skb)->gso_segs = 0; | |
1267 | } | |
6aa20a22 | 1268 | |
0690899b MT |
1269 | /* copy skb_ubuf_info for callback when skb has no error */ |
1270 | if (zerocopy) { | |
1271 | skb_shinfo(skb)->destructor_arg = msg_control; | |
1272 | skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; | |
c9af6db4 | 1273 | skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; |
0690899b MT |
1274 | } |
1275 | ||
72f65107 | 1276 | skb_reset_network_header(skb); |
40893fd0 | 1277 | skb_probe_transport_header(skb, 0); |
38502af7 | 1278 | |
3958afa1 | 1279 | rxhash = skb_get_hash(skb); |
1da177e4 | 1280 | netif_rx_ni(skb); |
6aa20a22 | 1281 | |
09f75cd7 JG |
1282 | tun->dev->stats.rx_packets++; |
1283 | tun->dev->stats.rx_bytes += len; | |
1da177e4 | 1284 | |
9e85722d | 1285 | tun_flow_update(tun, rxhash, tfile); |
0690899b | 1286 | return total_len; |
6aa20a22 | 1287 | } |
1da177e4 | 1288 | |
f5ff53b4 | 1289 | static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from) |
1da177e4 | 1290 | { |
33dccbb0 | 1291 | struct file *file = iocb->ki_filp; |
ab46d779 | 1292 | struct tun_struct *tun = tun_get(file); |
54f968d6 | 1293 | struct tun_file *tfile = file->private_data; |
631ab46b | 1294 | ssize_t result; |
1da177e4 LT |
1295 | |
1296 | if (!tun) | |
1297 | return -EBADFD; | |
1298 | ||
f5ff53b4 | 1299 | result = tun_get_user(tun, tfile, NULL, from, file->f_flags & O_NONBLOCK); |
631ab46b EB |
1300 | |
1301 | tun_put(tun); | |
1302 | return result; | |
1da177e4 LT |
1303 | } |
1304 | ||
1da177e4 | 1305 | /* Put packet to the user space buffer */ |
6f7c156c | 1306 | static ssize_t tun_put_user(struct tun_struct *tun, |
54f968d6 | 1307 | struct tun_file *tfile, |
6f7c156c | 1308 | struct sk_buff *skb, |
e0b46d0e | 1309 | struct iov_iter *iter) |
1da177e4 LT |
1310 | { |
1311 | struct tun_pi pi = { 0, skb->protocol }; | |
e0b46d0e | 1312 | ssize_t total; |
8c847d25 | 1313 | int vlan_offset = 0; |
a8f9bfdf | 1314 | int vlan_hlen = 0; |
2eb783c4 | 1315 | int vnet_hdr_sz = 0; |
a8f9bfdf | 1316 | |
df8a39de | 1317 | if (skb_vlan_tag_present(skb)) |
a8f9bfdf | 1318 | vlan_hlen = VLAN_HLEN; |
1da177e4 | 1319 | |
40630b82 | 1320 | if (tun->flags & IFF_VNET_HDR) |
2eb783c4 | 1321 | vnet_hdr_sz = tun->vnet_hdr_sz; |
1da177e4 | 1322 | |
e0b46d0e HX |
1323 | total = skb->len + vlan_hlen + vnet_hdr_sz; |
1324 | ||
40630b82 | 1325 | if (!(tun->flags & IFF_NO_PI)) { |
e0b46d0e | 1326 | if (iov_iter_count(iter) < sizeof(pi)) |
1da177e4 LT |
1327 | return -EINVAL; |
1328 | ||
e0b46d0e HX |
1329 | total += sizeof(pi); |
1330 | if (iov_iter_count(iter) < total) { | |
1da177e4 LT |
1331 | /* Packet will be striped */ |
1332 | pi.flags |= TUN_PKT_STRIP; | |
1333 | } | |
6aa20a22 | 1334 | |
e0b46d0e | 1335 | if (copy_to_iter(&pi, sizeof(pi), iter) != sizeof(pi)) |
1da177e4 | 1336 | return -EFAULT; |
6aa20a22 | 1337 | } |
1da177e4 | 1338 | |
2eb783c4 | 1339 | if (vnet_hdr_sz) { |
f43798c2 | 1340 | struct virtio_net_hdr gso = { 0 }; /* no info leak */ |
e0b46d0e | 1341 | if (iov_iter_count(iter) < vnet_hdr_sz) |
f43798c2 RR |
1342 | return -EINVAL; |
1343 | ||
1344 | if (skb_is_gso(skb)) { | |
1345 | struct skb_shared_info *sinfo = skb_shinfo(skb); | |
1346 | ||
1347 | /* This is a hint as to how much should be linear. */ | |
56f0dcc5 MT |
1348 | gso.hdr_len = cpu_to_tun16(tun, skb_headlen(skb)); |
1349 | gso.gso_size = cpu_to_tun16(tun, sinfo->gso_size); | |
f43798c2 RR |
1350 | if (sinfo->gso_type & SKB_GSO_TCPV4) |
1351 | gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; | |
1352 | else if (sinfo->gso_type & SKB_GSO_TCPV6) | |
1353 | gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; | |
e3e3c423 VY |
1354 | else if (sinfo->gso_type & SKB_GSO_UDP) |
1355 | gso.gso_type = VIRTIO_NET_HDR_GSO_UDP; | |
ef3db4a5 | 1356 | else { |
6b8a66ee | 1357 | pr_err("unexpected GSO type: " |
ef3db4a5 | 1358 | "0x%x, gso_size %d, hdr_len %d\n", |
56f0dcc5 MT |
1359 | sinfo->gso_type, tun16_to_cpu(tun, gso.gso_size), |
1360 | tun16_to_cpu(tun, gso.hdr_len)); | |
ef3db4a5 MT |
1361 | print_hex_dump(KERN_ERR, "tun: ", |
1362 | DUMP_PREFIX_NONE, | |
1363 | 16, 1, skb->head, | |
56f0dcc5 | 1364 | min((int)tun16_to_cpu(tun, gso.hdr_len), 64), true); |
ef3db4a5 MT |
1365 | WARN_ON_ONCE(1); |
1366 | return -EINVAL; | |
1367 | } | |
f43798c2 RR |
1368 | if (sinfo->gso_type & SKB_GSO_TCP_ECN) |
1369 | gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN; | |
1370 | } else | |
1371 | gso.gso_type = VIRTIO_NET_HDR_GSO_NONE; | |
1372 | ||
1373 | if (skb->ip_summed == CHECKSUM_PARTIAL) { | |
1374 | gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; | |
56f0dcc5 MT |
1375 | gso.csum_start = cpu_to_tun16(tun, skb_checksum_start_offset(skb) + |
1376 | vlan_hlen); | |
1377 | gso.csum_offset = cpu_to_tun16(tun, skb->csum_offset); | |
10a8d94a JW |
1378 | } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) { |
1379 | gso.flags = VIRTIO_NET_HDR_F_DATA_VALID; | |
f43798c2 RR |
1380 | } /* else everything is zero */ |
1381 | ||
e0b46d0e | 1382 | if (copy_to_iter(&gso, sizeof(gso), iter) != sizeof(gso)) |
f43798c2 | 1383 | return -EFAULT; |
8c847d25 JW |
1384 | |
1385 | iov_iter_advance(iter, vnet_hdr_sz - sizeof(gso)); | |
f43798c2 RR |
1386 | } |
1387 | ||
a8f9bfdf | 1388 | if (vlan_hlen) { |
e0b46d0e | 1389 | int ret; |
6680ec68 JW |
1390 | struct { |
1391 | __be16 h_vlan_proto; | |
1392 | __be16 h_vlan_TCI; | |
1393 | } veth; | |
1394 | ||
1395 | veth.h_vlan_proto = skb->vlan_proto; | |
df8a39de | 1396 | veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb)); |
6680ec68 JW |
1397 | |
1398 | vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); | |
6680ec68 | 1399 | |
e0b46d0e HX |
1400 | ret = skb_copy_datagram_iter(skb, 0, iter, vlan_offset); |
1401 | if (ret || !iov_iter_count(iter)) | |
6680ec68 JW |
1402 | goto done; |
1403 | ||
e0b46d0e HX |
1404 | ret = copy_to_iter(&veth, sizeof(veth), iter); |
1405 | if (ret != sizeof(veth) || !iov_iter_count(iter)) | |
6680ec68 JW |
1406 | goto done; |
1407 | } | |
1da177e4 | 1408 | |
e0b46d0e | 1409 | skb_copy_datagram_iter(skb, vlan_offset, iter, skb->len - vlan_offset); |
1da177e4 | 1410 | |
6680ec68 | 1411 | done: |
09f75cd7 | 1412 | tun->dev->stats.tx_packets++; |
e0b46d0e | 1413 | tun->dev->stats.tx_bytes += skb->len + vlan_hlen; |
1da177e4 LT |
1414 | |
1415 | return total; | |
1416 | } | |
1417 | ||
54f968d6 | 1418 | static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, |
9b067034 AV |
1419 | struct iov_iter *to, |
1420 | int noblock) | |
1da177e4 | 1421 | { |
1da177e4 | 1422 | struct sk_buff *skb; |
9b067034 | 1423 | ssize_t ret; |
9e641bdc | 1424 | int peeked, err, off = 0; |
1da177e4 | 1425 | |
3872baf6 | 1426 | tun_debug(KERN_INFO, tun, "tun_do_read\n"); |
1da177e4 | 1427 | |
9b067034 AV |
1428 | if (!iov_iter_count(to)) |
1429 | return 0; | |
1da177e4 | 1430 | |
9e641bdc XW |
1431 | if (tun->dev->reg_state != NETREG_REGISTERED) |
1432 | return -EIO; | |
1da177e4 | 1433 | |
9e641bdc XW |
1434 | /* Read frames from queue */ |
1435 | skb = __skb_recv_datagram(tfile->socket.sk, noblock ? MSG_DONTWAIT : 0, | |
1436 | &peeked, &off, &err); | |
e0b46d0e | 1437 | if (!skb) |
957f094f | 1438 | return err; |
e0b46d0e | 1439 | |
9b067034 | 1440 | ret = tun_put_user(tun, tfile, skb, to); |
f51a5e82 | 1441 | if (unlikely(ret < 0)) |
f271b2cc | 1442 | kfree_skb(skb); |
f51a5e82 JW |
1443 | else |
1444 | consume_skb(skb); | |
1da177e4 | 1445 | |
05c2828c MT |
1446 | return ret; |
1447 | } | |
1448 | ||
9b067034 | 1449 | static ssize_t tun_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) |
05c2828c MT |
1450 | { |
1451 | struct file *file = iocb->ki_filp; | |
1452 | struct tun_file *tfile = file->private_data; | |
1453 | struct tun_struct *tun = __tun_get(tfile); | |
9b067034 | 1454 | ssize_t len = iov_iter_count(to), ret; |
05c2828c MT |
1455 | |
1456 | if (!tun) | |
1457 | return -EBADFD; | |
9b067034 | 1458 | ret = tun_do_read(tun, tfile, to, file->f_flags & O_NONBLOCK); |
42404c09 | 1459 | ret = min_t(ssize_t, ret, len); |
d0b7da8a ZYW |
1460 | if (ret > 0) |
1461 | iocb->ki_pos = ret; | |
631ab46b | 1462 | tun_put(tun); |
1da177e4 LT |
1463 | return ret; |
1464 | } | |
1465 | ||
96442e42 JW |
1466 | static void tun_free_netdev(struct net_device *dev) |
1467 | { | |
1468 | struct tun_struct *tun = netdev_priv(dev); | |
1469 | ||
4008e97f | 1470 | BUG_ON(!(list_empty(&tun->disabled))); |
96442e42 | 1471 | tun_flow_uninit(tun); |
5dbbaf2d | 1472 | security_tun_dev_free_security(tun->security); |
96442e42 JW |
1473 | free_netdev(dev); |
1474 | } | |
1475 | ||
1da177e4 LT |
1476 | static void tun_setup(struct net_device *dev) |
1477 | { | |
1478 | struct tun_struct *tun = netdev_priv(dev); | |
1479 | ||
0625c883 EB |
1480 | tun->owner = INVALID_UID; |
1481 | tun->group = INVALID_GID; | |
1da177e4 | 1482 | |
1da177e4 | 1483 | dev->ethtool_ops = &tun_ethtool_ops; |
96442e42 | 1484 | dev->destructor = tun_free_netdev; |
1da177e4 LT |
1485 | } |
1486 | ||
f019a7a5 EB |
1487 | /* Trivial set of netlink ops to allow deleting tun or tap |
1488 | * device with netlink. | |
1489 | */ | |
1490 | static int tun_validate(struct nlattr *tb[], struct nlattr *data[]) | |
1491 | { | |
1492 | return -EINVAL; | |
1493 | } | |
1494 | ||
1495 | static struct rtnl_link_ops tun_link_ops __read_mostly = { | |
1496 | .kind = DRV_NAME, | |
1497 | .priv_size = sizeof(struct tun_struct), | |
1498 | .setup = tun_setup, | |
1499 | .validate = tun_validate, | |
1500 | }; | |
1501 | ||
33dccbb0 HX |
1502 | static void tun_sock_write_space(struct sock *sk) |
1503 | { | |
54f968d6 | 1504 | struct tun_file *tfile; |
43815482 | 1505 | wait_queue_head_t *wqueue; |
33dccbb0 HX |
1506 | |
1507 | if (!sock_writeable(sk)) | |
1508 | return; | |
1509 | ||
9cd3e072 | 1510 | if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags)) |
33dccbb0 HX |
1511 | return; |
1512 | ||
43815482 ED |
1513 | wqueue = sk_sleep(sk); |
1514 | if (wqueue && waitqueue_active(wqueue)) | |
1515 | wake_up_interruptible_sync_poll(wqueue, POLLOUT | | |
05c2828c | 1516 | POLLWRNORM | POLLWRBAND); |
c722c625 | 1517 | |
54f968d6 JW |
1518 | tfile = container_of(sk, struct tun_file, sk); |
1519 | kill_fasync(&tfile->fasync, SIGIO, POLL_OUT); | |
33dccbb0 HX |
1520 | } |
1521 | ||
1b784140 | 1522 | static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) |
05c2828c | 1523 | { |
54f968d6 JW |
1524 | int ret; |
1525 | struct tun_file *tfile = container_of(sock, struct tun_file, socket); | |
1526 | struct tun_struct *tun = __tun_get(tfile); | |
1527 | ||
1528 | if (!tun) | |
1529 | return -EBADFD; | |
f5ff53b4 | 1530 | |
c0371da6 | 1531 | ret = tun_get_user(tun, tfile, m->msg_control, &m->msg_iter, |
f5ff53b4 | 1532 | m->msg_flags & MSG_DONTWAIT); |
54f968d6 JW |
1533 | tun_put(tun); |
1534 | return ret; | |
05c2828c MT |
1535 | } |
1536 | ||
1b784140 | 1537 | static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, |
05c2828c MT |
1538 | int flags) |
1539 | { | |
54f968d6 JW |
1540 | struct tun_file *tfile = container_of(sock, struct tun_file, socket); |
1541 | struct tun_struct *tun = __tun_get(tfile); | |
05c2828c | 1542 | int ret; |
54f968d6 JW |
1543 | |
1544 | if (!tun) | |
1545 | return -EBADFD; | |
1546 | ||
eda29772 | 1547 | if (flags & ~(MSG_DONTWAIT|MSG_TRUNC|MSG_ERRQUEUE)) { |
3811ae76 G |
1548 | ret = -EINVAL; |
1549 | goto out; | |
1550 | } | |
eda29772 RC |
1551 | if (flags & MSG_ERRQUEUE) { |
1552 | ret = sock_recv_errqueue(sock->sk, m, total_len, | |
1553 | SOL_PACKET, TUN_TX_TIMESTAMP); | |
1554 | goto out; | |
1555 | } | |
c0371da6 | 1556 | ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT); |
87897931 | 1557 | if (ret > (ssize_t)total_len) { |
42404c09 DM |
1558 | m->msg_flags |= MSG_TRUNC; |
1559 | ret = flags & MSG_TRUNC ? ret : total_len; | |
1560 | } | |
3811ae76 | 1561 | out: |
54f968d6 | 1562 | tun_put(tun); |
05c2828c MT |
1563 | return ret; |
1564 | } | |
1565 | ||
1566 | /* Ops structure to mimic raw sockets with tun */ | |
1567 | static const struct proto_ops tun_socket_ops = { | |
1568 | .sendmsg = tun_sendmsg, | |
1569 | .recvmsg = tun_recvmsg, | |
1570 | }; | |
1571 | ||
33dccbb0 HX |
1572 | static struct proto tun_proto = { |
1573 | .name = "tun", | |
1574 | .owner = THIS_MODULE, | |
54f968d6 | 1575 | .obj_size = sizeof(struct tun_file), |
33dccbb0 | 1576 | }; |
f019a7a5 | 1577 | |
980c9e8c DW |
1578 | static int tun_flags(struct tun_struct *tun) |
1579 | { | |
031f5e03 | 1580 | return tun->flags & (TUN_FEATURES | IFF_PERSIST | IFF_TUN | IFF_TAP); |
980c9e8c DW |
1581 | } |
1582 | ||
1583 | static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr, | |
1584 | char *buf) | |
1585 | { | |
1586 | struct tun_struct *tun = netdev_priv(to_net_dev(dev)); | |
1587 | return sprintf(buf, "0x%x\n", tun_flags(tun)); | |
1588 | } | |
1589 | ||
1590 | static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr, | |
1591 | char *buf) | |
1592 | { | |
1593 | struct tun_struct *tun = netdev_priv(to_net_dev(dev)); | |
0625c883 EB |
1594 | return uid_valid(tun->owner)? |
1595 | sprintf(buf, "%u\n", | |
1596 | from_kuid_munged(current_user_ns(), tun->owner)): | |
1597 | sprintf(buf, "-1\n"); | |
980c9e8c DW |
1598 | } |
1599 | ||
1600 | static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr, | |
1601 | char *buf) | |
1602 | { | |
1603 | struct tun_struct *tun = netdev_priv(to_net_dev(dev)); | |
0625c883 EB |
1604 | return gid_valid(tun->group) ? |
1605 | sprintf(buf, "%u\n", | |
1606 | from_kgid_munged(current_user_ns(), tun->group)): | |
1607 | sprintf(buf, "-1\n"); | |
980c9e8c DW |
1608 | } |
1609 | ||
1610 | static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL); | |
1611 | static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL); | |
1612 | static DEVICE_ATTR(group, 0444, tun_show_group, NULL); | |
1613 | ||
c4d33e24 TI |
1614 | static struct attribute *tun_dev_attrs[] = { |
1615 | &dev_attr_tun_flags.attr, | |
1616 | &dev_attr_owner.attr, | |
1617 | &dev_attr_group.attr, | |
1618 | NULL | |
1619 | }; | |
1620 | ||
1621 | static const struct attribute_group tun_attr_group = { | |
1622 | .attrs = tun_dev_attrs | |
1623 | }; | |
1624 | ||
d647a591 | 1625 | static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) |
1da177e4 LT |
1626 | { |
1627 | struct tun_struct *tun; | |
54f968d6 | 1628 | struct tun_file *tfile = file->private_data; |
1da177e4 LT |
1629 | struct net_device *dev; |
1630 | int err; | |
1631 | ||
7c0c3b1a JW |
1632 | if (tfile->detached) |
1633 | return -EINVAL; | |
1634 | ||
74a3e5a7 EB |
1635 | dev = __dev_get_by_name(net, ifr->ifr_name); |
1636 | if (dev) { | |
f85ba780 DW |
1637 | if (ifr->ifr_flags & IFF_TUN_EXCL) |
1638 | return -EBUSY; | |
74a3e5a7 EB |
1639 | if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops) |
1640 | tun = netdev_priv(dev); | |
1641 | else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops) | |
1642 | tun = netdev_priv(dev); | |
1643 | else | |
1644 | return -EINVAL; | |
1645 | ||
8e6d91ae | 1646 | if (!!(ifr->ifr_flags & IFF_MULTI_QUEUE) != |
40630b82 | 1647 | !!(tun->flags & IFF_MULTI_QUEUE)) |
8e6d91ae JW |
1648 | return -EINVAL; |
1649 | ||
cde8b15f | 1650 | if (tun_not_capable(tun)) |
2b980dbd | 1651 | return -EPERM; |
5dbbaf2d | 1652 | err = security_tun_dev_open(tun->security); |
2b980dbd PM |
1653 | if (err < 0) |
1654 | return err; | |
1655 | ||
849c9b6f | 1656 | err = tun_attach(tun, file, ifr->ifr_flags & IFF_NOFILTER); |
a7385ba2 EB |
1657 | if (err < 0) |
1658 | return err; | |
4008e97f | 1659 | |
40630b82 | 1660 | if (tun->flags & IFF_MULTI_QUEUE && |
e8dbad66 JW |
1661 | (tun->numqueues + tun->numdisabled > 1)) { |
1662 | /* One or more queue has already been attached, no need | |
1663 | * to initialize the device again. | |
1664 | */ | |
1665 | return 0; | |
1666 | } | |
6aa20a22 | 1667 | } |
1da177e4 LT |
1668 | else { |
1669 | char *name; | |
1670 | unsigned long flags = 0; | |
edfb6a14 JW |
1671 | int queues = ifr->ifr_flags & IFF_MULTI_QUEUE ? |
1672 | MAX_TAP_QUEUES : 1; | |
1da177e4 | 1673 | |
c260b772 | 1674 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
ca6bb5d7 | 1675 | return -EPERM; |
2b980dbd PM |
1676 | err = security_tun_dev_create(); |
1677 | if (err < 0) | |
1678 | return err; | |
ca6bb5d7 | 1679 | |
1da177e4 LT |
1680 | /* Set dev type */ |
1681 | if (ifr->ifr_flags & IFF_TUN) { | |
1682 | /* TUN device */ | |
40630b82 | 1683 | flags |= IFF_TUN; |
1da177e4 LT |
1684 | name = "tun%d"; |
1685 | } else if (ifr->ifr_flags & IFF_TAP) { | |
1686 | /* TAP device */ | |
40630b82 | 1687 | flags |= IFF_TAP; |
1da177e4 | 1688 | name = "tap%d"; |
6aa20a22 | 1689 | } else |
36989b90 | 1690 | return -EINVAL; |
6aa20a22 | 1691 | |
1da177e4 LT |
1692 | if (*ifr->ifr_name) |
1693 | name = ifr->ifr_name; | |
1694 | ||
c8d68e6b | 1695 | dev = alloc_netdev_mqs(sizeof(struct tun_struct), name, |
c835a677 TG |
1696 | NET_NAME_UNKNOWN, tun_setup, queues, |
1697 | queues); | |
edfb6a14 | 1698 | |
1da177e4 LT |
1699 | if (!dev) |
1700 | return -ENOMEM; | |
1701 | ||
fc54c658 | 1702 | dev_net_set(dev, net); |
f019a7a5 | 1703 | dev->rtnl_link_ops = &tun_link_ops; |
fb7589a1 | 1704 | dev->ifindex = tfile->ifindex; |
c4d33e24 | 1705 | dev->sysfs_groups[0] = &tun_attr_group; |
758e43b7 | 1706 | |
1da177e4 LT |
1707 | tun = netdev_priv(dev); |
1708 | tun->dev = dev; | |
1709 | tun->flags = flags; | |
f271b2cc | 1710 | tun->txflt.count = 0; |
d9d52b51 | 1711 | tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr); |
33dccbb0 | 1712 | |
eaea34b2 | 1713 | tun->align = NET_SKB_PAD; |
54f968d6 JW |
1714 | tun->filter_attached = false; |
1715 | tun->sndbuf = tfile->socket.sk->sk_sndbuf; | |
33dccbb0 | 1716 | |
96442e42 JW |
1717 | spin_lock_init(&tun->lock); |
1718 | ||
5dbbaf2d PM |
1719 | err = security_tun_dev_alloc_security(&tun->security); |
1720 | if (err < 0) | |
1721 | goto err_free_dev; | |
2b980dbd | 1722 | |
1da177e4 | 1723 | tun_net_init(dev); |
944a1376 | 1724 | tun_flow_init(tun); |
96442e42 | 1725 | |
88255375 | 1726 | dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | |
6680ec68 JW |
1727 | TUN_USER_FEATURES | NETIF_F_HW_VLAN_CTAG_TX | |
1728 | NETIF_F_HW_VLAN_STAG_TX; | |
88255375 | 1729 | dev->features = dev->hw_features; |
6671b224 FLVC |
1730 | dev->vlan_features = dev->features & |
1731 | ~(NETIF_F_HW_VLAN_CTAG_TX | | |
1732 | NETIF_F_HW_VLAN_STAG_TX); | |
88255375 | 1733 | |
4008e97f | 1734 | INIT_LIST_HEAD(&tun->disabled); |
849c9b6f | 1735 | err = tun_attach(tun, file, false); |
eb0fb363 | 1736 | if (err < 0) |
662ca437 | 1737 | goto err_free_flow; |
eb0fb363 | 1738 | |
1da177e4 LT |
1739 | err = register_netdevice(tun->dev); |
1740 | if (err < 0) | |
662ca437 | 1741 | goto err_detach; |
1da177e4 LT |
1742 | } |
1743 | ||
af668b3c MT |
1744 | netif_carrier_on(tun->dev); |
1745 | ||
6b8a66ee | 1746 | tun_debug(KERN_INFO, tun, "tun_set_iff\n"); |
1da177e4 | 1747 | |
031f5e03 MT |
1748 | tun->flags = (tun->flags & ~TUN_FEATURES) | |
1749 | (ifr->ifr_flags & TUN_FEATURES); | |
c8d68e6b | 1750 | |
e35259a9 MK |
1751 | /* Make sure persistent devices do not get stuck in |
1752 | * xoff state. | |
1753 | */ | |
1754 | if (netif_running(tun->dev)) | |
c8d68e6b | 1755 | netif_tx_wake_all_queues(tun->dev); |
e35259a9 | 1756 | |
1da177e4 LT |
1757 | strcpy(ifr->ifr_name, tun->dev->name); |
1758 | return 0; | |
1759 | ||
662ca437 JW |
1760 | err_detach: |
1761 | tun_detach_all(dev); | |
1762 | err_free_flow: | |
1763 | tun_flow_uninit(tun); | |
1764 | security_tun_dev_free_security(tun->security); | |
1765 | err_free_dev: | |
1da177e4 | 1766 | free_netdev(dev); |
1da177e4 LT |
1767 | return err; |
1768 | } | |
1769 | ||
9ce99cf6 | 1770 | static void tun_get_iff(struct net *net, struct tun_struct *tun, |
876bfd4d | 1771 | struct ifreq *ifr) |
e3b99556 | 1772 | { |
6b8a66ee | 1773 | tun_debug(KERN_INFO, tun, "tun_get_iff\n"); |
e3b99556 MM |
1774 | |
1775 | strcpy(ifr->ifr_name, tun->dev->name); | |
1776 | ||
980c9e8c | 1777 | ifr->ifr_flags = tun_flags(tun); |
e3b99556 | 1778 | |
e3b99556 MM |
1779 | } |
1780 | ||
5228ddc9 RR |
1781 | /* This is like a cut-down ethtool ops, except done via tun fd so no |
1782 | * privs required. */ | |
88255375 | 1783 | static int set_offload(struct tun_struct *tun, unsigned long arg) |
5228ddc9 | 1784 | { |
c8f44aff | 1785 | netdev_features_t features = 0; |
5228ddc9 RR |
1786 | |
1787 | if (arg & TUN_F_CSUM) { | |
88255375 | 1788 | features |= NETIF_F_HW_CSUM; |
5228ddc9 RR |
1789 | arg &= ~TUN_F_CSUM; |
1790 | ||
1791 | if (arg & (TUN_F_TSO4|TUN_F_TSO6)) { | |
1792 | if (arg & TUN_F_TSO_ECN) { | |
1793 | features |= NETIF_F_TSO_ECN; | |
1794 | arg &= ~TUN_F_TSO_ECN; | |
1795 | } | |
1796 | if (arg & TUN_F_TSO4) | |
1797 | features |= NETIF_F_TSO; | |
1798 | if (arg & TUN_F_TSO6) | |
1799 | features |= NETIF_F_TSO6; | |
1800 | arg &= ~(TUN_F_TSO4|TUN_F_TSO6); | |
1801 | } | |
e3e3c423 VY |
1802 | |
1803 | if (arg & TUN_F_UFO) { | |
1804 | features |= NETIF_F_UFO; | |
1805 | arg &= ~TUN_F_UFO; | |
1806 | } | |
5228ddc9 RR |
1807 | } |
1808 | ||
1809 | /* This gives the user a way to test for new features in future by | |
1810 | * trying to set them. */ | |
1811 | if (arg) | |
1812 | return -EINVAL; | |
1813 | ||
88255375 MM |
1814 | tun->set_features = features; |
1815 | netdev_update_features(tun->dev); | |
5228ddc9 RR |
1816 | |
1817 | return 0; | |
1818 | } | |
1819 | ||
c8d68e6b JW |
1820 | static void tun_detach_filter(struct tun_struct *tun, int n) |
1821 | { | |
1822 | int i; | |
1823 | struct tun_file *tfile; | |
1824 | ||
1825 | for (i = 0; i < n; i++) { | |
b8deabd3 | 1826 | tfile = rtnl_dereference(tun->tfiles[i]); |
5a5abb1f | 1827 | __sk_detach_filter(tfile->socket.sk, lockdep_rtnl_is_held()); |
c8d68e6b JW |
1828 | } |
1829 | ||
1830 | tun->filter_attached = false; | |
1831 | } | |
1832 | ||
1833 | static int tun_attach_filter(struct tun_struct *tun) | |
1834 | { | |
1835 | int i, ret = 0; | |
1836 | struct tun_file *tfile; | |
1837 | ||
1838 | for (i = 0; i < tun->numqueues; i++) { | |
b8deabd3 | 1839 | tfile = rtnl_dereference(tun->tfiles[i]); |
5a5abb1f DB |
1840 | ret = __sk_attach_filter(&tun->fprog, tfile->socket.sk, |
1841 | lockdep_rtnl_is_held()); | |
c8d68e6b JW |
1842 | if (ret) { |
1843 | tun_detach_filter(tun, i); | |
1844 | return ret; | |
1845 | } | |
1846 | } | |
1847 | ||
1848 | tun->filter_attached = true; | |
1849 | return ret; | |
1850 | } | |
1851 | ||
1852 | static void tun_set_sndbuf(struct tun_struct *tun) | |
1853 | { | |
1854 | struct tun_file *tfile; | |
1855 | int i; | |
1856 | ||
1857 | for (i = 0; i < tun->numqueues; i++) { | |
b8deabd3 | 1858 | tfile = rtnl_dereference(tun->tfiles[i]); |
c8d68e6b JW |
1859 | tfile->socket.sk->sk_sndbuf = tun->sndbuf; |
1860 | } | |
1861 | } | |
1862 | ||
cde8b15f JW |
1863 | static int tun_set_queue(struct file *file, struct ifreq *ifr) |
1864 | { | |
1865 | struct tun_file *tfile = file->private_data; | |
1866 | struct tun_struct *tun; | |
cde8b15f JW |
1867 | int ret = 0; |
1868 | ||
1869 | rtnl_lock(); | |
1870 | ||
1871 | if (ifr->ifr_flags & IFF_ATTACH_QUEUE) { | |
4008e97f | 1872 | tun = tfile->detached; |
5dbbaf2d | 1873 | if (!tun) { |
cde8b15f | 1874 | ret = -EINVAL; |
5dbbaf2d PM |
1875 | goto unlock; |
1876 | } | |
1877 | ret = security_tun_dev_attach_queue(tun->security); | |
1878 | if (ret < 0) | |
1879 | goto unlock; | |
849c9b6f | 1880 | ret = tun_attach(tun, file, false); |
4008e97f | 1881 | } else if (ifr->ifr_flags & IFF_DETACH_QUEUE) { |
b8deabd3 | 1882 | tun = rtnl_dereference(tfile->tun); |
40630b82 | 1883 | if (!tun || !(tun->flags & IFF_MULTI_QUEUE) || tfile->detached) |
4008e97f JW |
1884 | ret = -EINVAL; |
1885 | else | |
1886 | __tun_detach(tfile, false); | |
1887 | } else | |
cde8b15f JW |
1888 | ret = -EINVAL; |
1889 | ||
5dbbaf2d | 1890 | unlock: |
cde8b15f JW |
1891 | rtnl_unlock(); |
1892 | return ret; | |
1893 | } | |
1894 | ||
50857e2a AB |
1895 | static long __tun_chr_ioctl(struct file *file, unsigned int cmd, |
1896 | unsigned long arg, int ifreq_len) | |
1da177e4 | 1897 | { |
36b50bab | 1898 | struct tun_file *tfile = file->private_data; |
631ab46b | 1899 | struct tun_struct *tun; |
1da177e4 LT |
1900 | void __user* argp = (void __user*)arg; |
1901 | struct ifreq ifr; | |
0625c883 EB |
1902 | kuid_t owner; |
1903 | kgid_t group; | |
33dccbb0 | 1904 | int sndbuf; |
d9d52b51 | 1905 | int vnet_hdr_sz; |
fb7589a1 | 1906 | unsigned int ifindex; |
1cf8e410 | 1907 | int le; |
f271b2cc | 1908 | int ret; |
1da177e4 | 1909 | |
cde8b15f | 1910 | if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) == 0x89) { |
50857e2a | 1911 | if (copy_from_user(&ifr, argp, ifreq_len)) |
1da177e4 | 1912 | return -EFAULT; |
8bbb1813 | 1913 | } else { |
a117dacd | 1914 | memset(&ifr, 0, sizeof(ifr)); |
8bbb1813 | 1915 | } |
631ab46b EB |
1916 | if (cmd == TUNGETFEATURES) { |
1917 | /* Currently this just means: "what IFF flags are valid?". | |
1918 | * This is needed because we never checked for invalid flags on | |
031f5e03 MT |
1919 | * TUNSETIFF. |
1920 | */ | |
1921 | return put_user(IFF_TUN | IFF_TAP | TUN_FEATURES, | |
631ab46b | 1922 | (unsigned int __user*)argp); |
cde8b15f JW |
1923 | } else if (cmd == TUNSETQUEUE) |
1924 | return tun_set_queue(file, &ifr); | |
631ab46b | 1925 | |
c8d68e6b | 1926 | ret = 0; |
876bfd4d HX |
1927 | rtnl_lock(); |
1928 | ||
36b50bab | 1929 | tun = __tun_get(tfile); |
1da177e4 | 1930 | if (cmd == TUNSETIFF && !tun) { |
1da177e4 LT |
1931 | ifr.ifr_name[IFNAMSIZ-1] = '\0'; |
1932 | ||
140e807d | 1933 | ret = tun_set_iff(sock_net(&tfile->sk), file, &ifr); |
1da177e4 | 1934 | |
876bfd4d HX |
1935 | if (ret) |
1936 | goto unlock; | |
1da177e4 | 1937 | |
50857e2a | 1938 | if (copy_to_user(argp, &ifr, ifreq_len)) |
876bfd4d HX |
1939 | ret = -EFAULT; |
1940 | goto unlock; | |
1da177e4 | 1941 | } |
fb7589a1 PE |
1942 | if (cmd == TUNSETIFINDEX) { |
1943 | ret = -EPERM; | |
1944 | if (tun) | |
1945 | goto unlock; | |
1946 | ||
1947 | ret = -EFAULT; | |
1948 | if (copy_from_user(&ifindex, argp, sizeof(ifindex))) | |
1949 | goto unlock; | |
1950 | ||
1951 | ret = 0; | |
1952 | tfile->ifindex = ifindex; | |
1953 | goto unlock; | |
1954 | } | |
1da177e4 | 1955 | |
876bfd4d | 1956 | ret = -EBADFD; |
1da177e4 | 1957 | if (!tun) |
876bfd4d | 1958 | goto unlock; |
1da177e4 | 1959 | |
1e588338 | 1960 | tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %u\n", cmd); |
1da177e4 | 1961 | |
631ab46b | 1962 | ret = 0; |
1da177e4 | 1963 | switch (cmd) { |
e3b99556 | 1964 | case TUNGETIFF: |
9ce99cf6 | 1965 | tun_get_iff(current->nsproxy->net_ns, tun, &ifr); |
e3b99556 | 1966 | |
3d407a80 PE |
1967 | if (tfile->detached) |
1968 | ifr.ifr_flags |= IFF_DETACH_QUEUE; | |
849c9b6f PE |
1969 | if (!tfile->socket.sk->sk_filter) |
1970 | ifr.ifr_flags |= IFF_NOFILTER; | |
3d407a80 | 1971 | |
50857e2a | 1972 | if (copy_to_user(argp, &ifr, ifreq_len)) |
631ab46b | 1973 | ret = -EFAULT; |
e3b99556 MM |
1974 | break; |
1975 | ||
1da177e4 LT |
1976 | case TUNSETNOCSUM: |
1977 | /* Disable/Enable checksum */ | |
1da177e4 | 1978 | |
88255375 MM |
1979 | /* [unimplemented] */ |
1980 | tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n", | |
6b8a66ee | 1981 | arg ? "disabled" : "enabled"); |
1da177e4 LT |
1982 | break; |
1983 | ||
1984 | case TUNSETPERSIST: | |
54f968d6 JW |
1985 | /* Disable/Enable persist mode. Keep an extra reference to the |
1986 | * module to prevent the module being unprobed. | |
1987 | */ | |
40630b82 MT |
1988 | if (arg && !(tun->flags & IFF_PERSIST)) { |
1989 | tun->flags |= IFF_PERSIST; | |
54f968d6 | 1990 | __module_get(THIS_MODULE); |
dd38bd85 | 1991 | } |
40630b82 MT |
1992 | if (!arg && (tun->flags & IFF_PERSIST)) { |
1993 | tun->flags &= ~IFF_PERSIST; | |
54f968d6 JW |
1994 | module_put(THIS_MODULE); |
1995 | } | |
1da177e4 | 1996 | |
6b8a66ee JP |
1997 | tun_debug(KERN_INFO, tun, "persist %s\n", |
1998 | arg ? "enabled" : "disabled"); | |
1da177e4 LT |
1999 | break; |
2000 | ||
2001 | case TUNSETOWNER: | |
2002 | /* Set owner of the device */ | |
0625c883 EB |
2003 | owner = make_kuid(current_user_ns(), arg); |
2004 | if (!uid_valid(owner)) { | |
2005 | ret = -EINVAL; | |
2006 | break; | |
2007 | } | |
2008 | tun->owner = owner; | |
1e588338 | 2009 | tun_debug(KERN_INFO, tun, "owner set to %u\n", |
0625c883 | 2010 | from_kuid(&init_user_ns, tun->owner)); |
1da177e4 LT |
2011 | break; |
2012 | ||
8c644623 GG |
2013 | case TUNSETGROUP: |
2014 | /* Set group of the device */ | |
0625c883 EB |
2015 | group = make_kgid(current_user_ns(), arg); |
2016 | if (!gid_valid(group)) { | |
2017 | ret = -EINVAL; | |
2018 | break; | |
2019 | } | |
2020 | tun->group = group; | |
1e588338 | 2021 | tun_debug(KERN_INFO, tun, "group set to %u\n", |
0625c883 | 2022 | from_kgid(&init_user_ns, tun->group)); |
8c644623 GG |
2023 | break; |
2024 | ||
ff4cc3ac MK |
2025 | case TUNSETLINK: |
2026 | /* Only allow setting the type when the interface is down */ | |
2027 | if (tun->dev->flags & IFF_UP) { | |
6b8a66ee JP |
2028 | tun_debug(KERN_INFO, tun, |
2029 | "Linktype set failed because interface is up\n"); | |
48abfe05 | 2030 | ret = -EBUSY; |
ff4cc3ac MK |
2031 | } else { |
2032 | tun->dev->type = (int) arg; | |
6b8a66ee JP |
2033 | tun_debug(KERN_INFO, tun, "linktype set to %d\n", |
2034 | tun->dev->type); | |
48abfe05 | 2035 | ret = 0; |
ff4cc3ac | 2036 | } |
631ab46b | 2037 | break; |
ff4cc3ac | 2038 | |
1da177e4 LT |
2039 | #ifdef TUN_DEBUG |
2040 | case TUNSETDEBUG: | |
2041 | tun->debug = arg; | |
2042 | break; | |
2043 | #endif | |
5228ddc9 | 2044 | case TUNSETOFFLOAD: |
88255375 | 2045 | ret = set_offload(tun, arg); |
631ab46b | 2046 | break; |
5228ddc9 | 2047 | |
f271b2cc MK |
2048 | case TUNSETTXFILTER: |
2049 | /* Can be set only for TAPs */ | |
631ab46b | 2050 | ret = -EINVAL; |
40630b82 | 2051 | if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP) |
631ab46b | 2052 | break; |
c0e5a8c2 | 2053 | ret = update_filter(&tun->txflt, (void __user *)arg); |
631ab46b | 2054 | break; |
1da177e4 LT |
2055 | |
2056 | case SIOCGIFHWADDR: | |
b595076a | 2057 | /* Get hw address */ |
f271b2cc MK |
2058 | memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN); |
2059 | ifr.ifr_hwaddr.sa_family = tun->dev->type; | |
50857e2a | 2060 | if (copy_to_user(argp, &ifr, ifreq_len)) |
631ab46b EB |
2061 | ret = -EFAULT; |
2062 | break; | |
1da177e4 LT |
2063 | |
2064 | case SIOCSIFHWADDR: | |
f271b2cc | 2065 | /* Set hw address */ |
6b8a66ee JP |
2066 | tun_debug(KERN_DEBUG, tun, "set hw address: %pM\n", |
2067 | ifr.ifr_hwaddr.sa_data); | |
40102371 | 2068 | |
40102371 | 2069 | ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr); |
631ab46b | 2070 | break; |
33dccbb0 HX |
2071 | |
2072 | case TUNGETSNDBUF: | |
54f968d6 | 2073 | sndbuf = tfile->socket.sk->sk_sndbuf; |
33dccbb0 HX |
2074 | if (copy_to_user(argp, &sndbuf, sizeof(sndbuf))) |
2075 | ret = -EFAULT; | |
2076 | break; | |
2077 | ||
2078 | case TUNSETSNDBUF: | |
2079 | if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) { | |
2080 | ret = -EFAULT; | |
2081 | break; | |
2082 | } | |
2083 | ||
c8d68e6b JW |
2084 | tun->sndbuf = sndbuf; |
2085 | tun_set_sndbuf(tun); | |
33dccbb0 HX |
2086 | break; |
2087 | ||
d9d52b51 MT |
2088 | case TUNGETVNETHDRSZ: |
2089 | vnet_hdr_sz = tun->vnet_hdr_sz; | |
2090 | if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz))) | |
2091 | ret = -EFAULT; | |
2092 | break; | |
2093 | ||
2094 | case TUNSETVNETHDRSZ: | |
2095 | if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) { | |
2096 | ret = -EFAULT; | |
2097 | break; | |
2098 | } | |
2099 | if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) { | |
2100 | ret = -EINVAL; | |
2101 | break; | |
2102 | } | |
2103 | ||
2104 | tun->vnet_hdr_sz = vnet_hdr_sz; | |
2105 | break; | |
2106 | ||
1cf8e410 MT |
2107 | case TUNGETVNETLE: |
2108 | le = !!(tun->flags & TUN_VNET_LE); | |
2109 | if (put_user(le, (int __user *)argp)) | |
2110 | ret = -EFAULT; | |
2111 | break; | |
2112 | ||
2113 | case TUNSETVNETLE: | |
2114 | if (get_user(le, (int __user *)argp)) { | |
2115 | ret = -EFAULT; | |
2116 | break; | |
2117 | } | |
2118 | if (le) | |
2119 | tun->flags |= TUN_VNET_LE; | |
2120 | else | |
2121 | tun->flags &= ~TUN_VNET_LE; | |
2122 | break; | |
2123 | ||
8b8e658b GK |
2124 | case TUNGETVNETBE: |
2125 | ret = tun_get_vnet_be(tun, argp); | |
2126 | break; | |
2127 | ||
2128 | case TUNSETVNETBE: | |
2129 | ret = tun_set_vnet_be(tun, argp); | |
2130 | break; | |
2131 | ||
99405162 MT |
2132 | case TUNATTACHFILTER: |
2133 | /* Can be set only for TAPs */ | |
2134 | ret = -EINVAL; | |
40630b82 | 2135 | if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP) |
99405162 MT |
2136 | break; |
2137 | ret = -EFAULT; | |
54f968d6 | 2138 | if (copy_from_user(&tun->fprog, argp, sizeof(tun->fprog))) |
99405162 MT |
2139 | break; |
2140 | ||
c8d68e6b | 2141 | ret = tun_attach_filter(tun); |
99405162 MT |
2142 | break; |
2143 | ||
2144 | case TUNDETACHFILTER: | |
2145 | /* Can be set only for TAPs */ | |
2146 | ret = -EINVAL; | |
40630b82 | 2147 | if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP) |
99405162 | 2148 | break; |
c8d68e6b JW |
2149 | ret = 0; |
2150 | tun_detach_filter(tun, tun->numqueues); | |
99405162 MT |
2151 | break; |
2152 | ||
76975e9c PE |
2153 | case TUNGETFILTER: |
2154 | ret = -EINVAL; | |
40630b82 | 2155 | if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP) |
76975e9c PE |
2156 | break; |
2157 | ret = -EFAULT; | |
2158 | if (copy_to_user(argp, &tun->fprog, sizeof(tun->fprog))) | |
2159 | break; | |
2160 | ret = 0; | |
2161 | break; | |
2162 | ||
1da177e4 | 2163 | default: |
631ab46b EB |
2164 | ret = -EINVAL; |
2165 | break; | |
ee289b64 | 2166 | } |
1da177e4 | 2167 | |
876bfd4d HX |
2168 | unlock: |
2169 | rtnl_unlock(); | |
2170 | if (tun) | |
2171 | tun_put(tun); | |
631ab46b | 2172 | return ret; |
1da177e4 LT |
2173 | } |
2174 | ||
50857e2a AB |
2175 | static long tun_chr_ioctl(struct file *file, |
2176 | unsigned int cmd, unsigned long arg) | |
2177 | { | |
2178 | return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq)); | |
2179 | } | |
2180 | ||
2181 | #ifdef CONFIG_COMPAT | |
2182 | static long tun_chr_compat_ioctl(struct file *file, | |
2183 | unsigned int cmd, unsigned long arg) | |
2184 | { | |
2185 | switch (cmd) { | |
2186 | case TUNSETIFF: | |
2187 | case TUNGETIFF: | |
2188 | case TUNSETTXFILTER: | |
2189 | case TUNGETSNDBUF: | |
2190 | case TUNSETSNDBUF: | |
2191 | case SIOCGIFHWADDR: | |
2192 | case SIOCSIFHWADDR: | |
2193 | arg = (unsigned long)compat_ptr(arg); | |
2194 | break; | |
2195 | default: | |
2196 | arg = (compat_ulong_t)arg; | |
2197 | break; | |
2198 | } | |
2199 | ||
2200 | /* | |
2201 | * compat_ifreq is shorter than ifreq, so we must not access beyond | |
2202 | * the end of that structure. All fields that are used in this | |
2203 | * driver are compatible though, we don't need to convert the | |
2204 | * contents. | |
2205 | */ | |
2206 | return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq)); | |
2207 | } | |
2208 | #endif /* CONFIG_COMPAT */ | |
2209 | ||
1da177e4 LT |
2210 | static int tun_chr_fasync(int fd, struct file *file, int on) |
2211 | { | |
54f968d6 | 2212 | struct tun_file *tfile = file->private_data; |
1da177e4 LT |
2213 | int ret; |
2214 | ||
54f968d6 | 2215 | if ((ret = fasync_helper(fd, file, on, &tfile->fasync)) < 0) |
9d319522 | 2216 | goto out; |
6aa20a22 | 2217 | |
1da177e4 | 2218 | if (on) { |
e0b93edd | 2219 | __f_setown(file, task_pid(current), PIDTYPE_PID, 0); |
54f968d6 | 2220 | tfile->flags |= TUN_FASYNC; |
6aa20a22 | 2221 | } else |
54f968d6 | 2222 | tfile->flags &= ~TUN_FASYNC; |
9d319522 JC |
2223 | ret = 0; |
2224 | out: | |
9d319522 | 2225 | return ret; |
1da177e4 LT |
2226 | } |
2227 | ||
2228 | static int tun_chr_open(struct inode *inode, struct file * file) | |
2229 | { | |
140e807d | 2230 | struct net *net = current->nsproxy->net_ns; |
631ab46b | 2231 | struct tun_file *tfile; |
deed49fb | 2232 | |
6b8a66ee | 2233 | DBG1(KERN_INFO, "tunX: tun_chr_open\n"); |
631ab46b | 2234 | |
140e807d | 2235 | tfile = (struct tun_file *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL, |
11aa9c28 | 2236 | &tun_proto, 0); |
631ab46b EB |
2237 | if (!tfile) |
2238 | return -ENOMEM; | |
c956674b | 2239 | RCU_INIT_POINTER(tfile->tun, NULL); |
54f968d6 | 2240 | tfile->flags = 0; |
fb7589a1 | 2241 | tfile->ifindex = 0; |
54f968d6 | 2242 | |
54f968d6 | 2243 | init_waitqueue_head(&tfile->wq.wait); |
9e641bdc | 2244 | RCU_INIT_POINTER(tfile->socket.wq, &tfile->wq); |
54f968d6 JW |
2245 | |
2246 | tfile->socket.file = file; | |
2247 | tfile->socket.ops = &tun_socket_ops; | |
2248 | ||
2249 | sock_init_data(&tfile->socket, &tfile->sk); | |
54f968d6 JW |
2250 | |
2251 | tfile->sk.sk_write_space = tun_sock_write_space; | |
2252 | tfile->sk.sk_sndbuf = INT_MAX; | |
2253 | ||
631ab46b | 2254 | file->private_data = tfile; |
4008e97f | 2255 | INIT_LIST_HEAD(&tfile->next); |
54f968d6 | 2256 | |
19a6afb2 JW |
2257 | sock_set_flag(&tfile->sk, SOCK_ZEROCOPY); |
2258 | ||
1da177e4 LT |
2259 | return 0; |
2260 | } | |
2261 | ||
2262 | static int tun_chr_close(struct inode *inode, struct file *file) | |
2263 | { | |
631ab46b | 2264 | struct tun_file *tfile = file->private_data; |
1da177e4 | 2265 | |
c8d68e6b | 2266 | tun_detach(tfile, true); |
1da177e4 LT |
2267 | |
2268 | return 0; | |
2269 | } | |
2270 | ||
93e14b6d | 2271 | #ifdef CONFIG_PROC_FS |
a3816ab0 | 2272 | static void tun_chr_show_fdinfo(struct seq_file *m, struct file *f) |
93e14b6d MY |
2273 | { |
2274 | struct tun_struct *tun; | |
2275 | struct ifreq ifr; | |
2276 | ||
2277 | memset(&ifr, 0, sizeof(ifr)); | |
2278 | ||
2279 | rtnl_lock(); | |
2280 | tun = tun_get(f); | |
2281 | if (tun) | |
2282 | tun_get_iff(current->nsproxy->net_ns, tun, &ifr); | |
2283 | rtnl_unlock(); | |
2284 | ||
2285 | if (tun) | |
2286 | tun_put(tun); | |
2287 | ||
a3816ab0 | 2288 | seq_printf(m, "iff:\t%s\n", ifr.ifr_name); |
93e14b6d MY |
2289 | } |
2290 | #endif | |
2291 | ||
d54b1fdb | 2292 | static const struct file_operations tun_fops = { |
6aa20a22 | 2293 | .owner = THIS_MODULE, |
1da177e4 | 2294 | .llseek = no_llseek, |
9b067034 | 2295 | .read_iter = tun_chr_read_iter, |
f5ff53b4 | 2296 | .write_iter = tun_chr_write_iter, |
1da177e4 | 2297 | .poll = tun_chr_poll, |
50857e2a AB |
2298 | .unlocked_ioctl = tun_chr_ioctl, |
2299 | #ifdef CONFIG_COMPAT | |
2300 | .compat_ioctl = tun_chr_compat_ioctl, | |
2301 | #endif | |
1da177e4 LT |
2302 | .open = tun_chr_open, |
2303 | .release = tun_chr_close, | |
93e14b6d MY |
2304 | .fasync = tun_chr_fasync, |
2305 | #ifdef CONFIG_PROC_FS | |
2306 | .show_fdinfo = tun_chr_show_fdinfo, | |
2307 | #endif | |
1da177e4 LT |
2308 | }; |
2309 | ||
2310 | static struct miscdevice tun_miscdev = { | |
2311 | .minor = TUN_MINOR, | |
2312 | .name = "tun", | |
e454cea2 | 2313 | .nodename = "net/tun", |
1da177e4 | 2314 | .fops = &tun_fops, |
1da177e4 LT |
2315 | }; |
2316 | ||
2317 | /* ethtool interface */ | |
2318 | ||
2319 | static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) | |
2320 | { | |
2321 | cmd->supported = 0; | |
2322 | cmd->advertising = 0; | |
70739497 | 2323 | ethtool_cmd_speed_set(cmd, SPEED_10); |
1da177e4 LT |
2324 | cmd->duplex = DUPLEX_FULL; |
2325 | cmd->port = PORT_TP; | |
2326 | cmd->phy_address = 0; | |
2327 | cmd->transceiver = XCVR_INTERNAL; | |
2328 | cmd->autoneg = AUTONEG_DISABLE; | |
2329 | cmd->maxtxpkt = 0; | |
2330 | cmd->maxrxpkt = 0; | |
2331 | return 0; | |
2332 | } | |
2333 | ||
2334 | static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) | |
2335 | { | |
2336 | struct tun_struct *tun = netdev_priv(dev); | |
2337 | ||
33a5ba14 RJ |
2338 | strlcpy(info->driver, DRV_NAME, sizeof(info->driver)); |
2339 | strlcpy(info->version, DRV_VERSION, sizeof(info->version)); | |
1da177e4 LT |
2340 | |
2341 | switch (tun->flags & TUN_TYPE_MASK) { | |
40630b82 | 2342 | case IFF_TUN: |
33a5ba14 | 2343 | strlcpy(info->bus_info, "tun", sizeof(info->bus_info)); |
1da177e4 | 2344 | break; |
40630b82 | 2345 | case IFF_TAP: |
33a5ba14 | 2346 | strlcpy(info->bus_info, "tap", sizeof(info->bus_info)); |
1da177e4 LT |
2347 | break; |
2348 | } | |
2349 | } | |
2350 | ||
2351 | static u32 tun_get_msglevel(struct net_device *dev) | |
2352 | { | |
2353 | #ifdef TUN_DEBUG | |
2354 | struct tun_struct *tun = netdev_priv(dev); | |
2355 | return tun->debug; | |
2356 | #else | |
2357 | return -EOPNOTSUPP; | |
2358 | #endif | |
2359 | } | |
2360 | ||
2361 | static void tun_set_msglevel(struct net_device *dev, u32 value) | |
2362 | { | |
2363 | #ifdef TUN_DEBUG | |
2364 | struct tun_struct *tun = netdev_priv(dev); | |
2365 | tun->debug = value; | |
2366 | #endif | |
2367 | } | |
2368 | ||
7282d491 | 2369 | static const struct ethtool_ops tun_ethtool_ops = { |
1da177e4 LT |
2370 | .get_settings = tun_get_settings, |
2371 | .get_drvinfo = tun_get_drvinfo, | |
2372 | .get_msglevel = tun_get_msglevel, | |
2373 | .set_msglevel = tun_set_msglevel, | |
bee31369 | 2374 | .get_link = ethtool_op_get_link, |
eda29772 | 2375 | .get_ts_info = ethtool_op_get_ts_info, |
1da177e4 LT |
2376 | }; |
2377 | ||
79d17604 | 2378 | |
1da177e4 LT |
2379 | static int __init tun_init(void) |
2380 | { | |
2381 | int ret = 0; | |
2382 | ||
6b8a66ee JP |
2383 | pr_info("%s, %s\n", DRV_DESCRIPTION, DRV_VERSION); |
2384 | pr_info("%s\n", DRV_COPYRIGHT); | |
1da177e4 | 2385 | |
f019a7a5 | 2386 | ret = rtnl_link_register(&tun_link_ops); |
79d17604 | 2387 | if (ret) { |
6b8a66ee | 2388 | pr_err("Can't register link_ops\n"); |
f019a7a5 | 2389 | goto err_linkops; |
79d17604 PE |
2390 | } |
2391 | ||
1da177e4 | 2392 | ret = misc_register(&tun_miscdev); |
79d17604 | 2393 | if (ret) { |
6b8a66ee | 2394 | pr_err("Can't register misc device %d\n", TUN_MINOR); |
79d17604 PE |
2395 | goto err_misc; |
2396 | } | |
f019a7a5 | 2397 | return 0; |
79d17604 | 2398 | err_misc: |
f019a7a5 EB |
2399 | rtnl_link_unregister(&tun_link_ops); |
2400 | err_linkops: | |
1da177e4 LT |
2401 | return ret; |
2402 | } | |
2403 | ||
2404 | static void tun_cleanup(void) | |
2405 | { | |
6aa20a22 | 2406 | misc_deregister(&tun_miscdev); |
f019a7a5 | 2407 | rtnl_link_unregister(&tun_link_ops); |
1da177e4 LT |
2408 | } |
2409 | ||
05c2828c MT |
2410 | /* Get an underlying socket object from tun file. Returns error unless file is |
2411 | * attached to a device. The returned object works like a packet socket, it | |
2412 | * can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for | |
2413 | * holding a reference to the file for as long as the socket is in use. */ | |
2414 | struct socket *tun_get_socket(struct file *file) | |
2415 | { | |
6e914fc7 | 2416 | struct tun_file *tfile; |
05c2828c MT |
2417 | if (file->f_op != &tun_fops) |
2418 | return ERR_PTR(-EINVAL); | |
6e914fc7 JW |
2419 | tfile = file->private_data; |
2420 | if (!tfile) | |
05c2828c | 2421 | return ERR_PTR(-EBADFD); |
54f968d6 | 2422 | return &tfile->socket; |
05c2828c MT |
2423 | } |
2424 | EXPORT_SYMBOL_GPL(tun_get_socket); | |
2425 | ||
1da177e4 LT |
2426 | module_init(tun_init); |
2427 | module_exit(tun_cleanup); | |
2428 | MODULE_DESCRIPTION(DRV_DESCRIPTION); | |
2429 | MODULE_AUTHOR(DRV_COPYRIGHT); | |
2430 | MODULE_LICENSE("GPL"); | |
2431 | MODULE_ALIAS_MISCDEV(TUN_MINOR); | |
578454ff | 2432 | MODULE_ALIAS("devname:net/tun"); |