tun.c 33 KB

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  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. * Changes:
  19. *
  20. * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
  21. * Add TUNSETLINK ioctl to set the link encapsulation
  22. *
  23. * Mark Smith <markzzzsmith@yahoo.com.au>
  24. * Use random_ether_addr() for tap MAC address.
  25. *
  26. * Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20
  27. * Fixes in packet dropping, queue length setting and queue wakeup.
  28. * Increased default tx queue length.
  29. * Added ethtool API.
  30. * Minor cleanups
  31. *
  32. * Daniel Podlejski <underley@underley.eu.org>
  33. * Modifications for 2.3.99-pre5 kernel.
  34. */
  35. #define DRV_NAME "tun"
  36. #define DRV_VERSION "1.6"
  37. #define DRV_DESCRIPTION "Universal TUN/TAP device driver"
  38. #define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
  39. #include <linux/module.h>
  40. #include <linux/errno.h>
  41. #include <linux/kernel.h>
  42. #include <linux/major.h>
  43. #include <linux/slab.h>
  44. #include <linux/smp_lock.h>
  45. #include <linux/poll.h>
  46. #include <linux/fcntl.h>
  47. #include <linux/init.h>
  48. #include <linux/skbuff.h>
  49. #include <linux/netdevice.h>
  50. #include <linux/etherdevice.h>
  51. #include <linux/miscdevice.h>
  52. #include <linux/ethtool.h>
  53. #include <linux/rtnetlink.h>
  54. #include <linux/if.h>
  55. #include <linux/if_arp.h>
  56. #include <linux/if_ether.h>
  57. #include <linux/if_tun.h>
  58. #include <linux/crc32.h>
  59. #include <linux/nsproxy.h>
  60. #include <linux/virtio_net.h>
  61. #include <net/net_namespace.h>
  62. #include <net/netns/generic.h>
  63. #include <net/rtnetlink.h>
  64. #include <net/sock.h>
  65. #include <asm/system.h>
  66. #include <asm/uaccess.h>
  67. /* Uncomment to enable debugging */
  68. /* #define TUN_DEBUG 1 */
  69. #ifdef TUN_DEBUG
  70. static int debug;
  71. #define DBG if(tun->debug)printk
  72. #define DBG1 if(debug==2)printk
  73. #else
  74. #define DBG( a... )
  75. #define DBG1( a... )
  76. #endif
  77. #define FLT_EXACT_COUNT 8
  78. struct tap_filter {
  79. unsigned int count; /* Number of addrs. Zero means disabled */
  80. u32 mask[2]; /* Mask of the hashed addrs */
  81. unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
  82. };
  83. struct tun_file {
  84. atomic_t count;
  85. struct tun_struct *tun;
  86. struct net *net;
  87. };
  88. struct tun_sock;
  89. struct tun_struct {
  90. struct tun_file *tfile;
  91. unsigned int flags;
  92. uid_t owner;
  93. gid_t group;
  94. struct sk_buff_head readq;
  95. struct net_device *dev;
  96. struct fasync_struct *fasync;
  97. struct tap_filter txflt;
  98. struct sock *sk;
  99. struct socket socket;
  100. #ifdef TUN_DEBUG
  101. int debug;
  102. #endif
  103. };
  104. struct tun_sock {
  105. struct sock sk;
  106. struct tun_struct *tun;
  107. };
  108. static inline struct tun_sock *tun_sk(struct sock *sk)
  109. {
  110. return container_of(sk, struct tun_sock, sk);
  111. }
  112. static int tun_attach(struct tun_struct *tun, struct file *file)
  113. {
  114. struct tun_file *tfile = file->private_data;
  115. const struct cred *cred = current_cred();
  116. int err;
  117. ASSERT_RTNL();
  118. /* Check permissions */
  119. if (((tun->owner != -1 && cred->euid != tun->owner) ||
  120. (tun->group != -1 && !in_egroup_p(tun->group))) &&
  121. !capable(CAP_NET_ADMIN))
  122. return -EPERM;
  123. netif_tx_lock_bh(tun->dev);
  124. err = -EINVAL;
  125. if (tfile->tun)
  126. goto out;
  127. err = -EBUSY;
  128. if (tun->tfile)
  129. goto out;
  130. err = 0;
  131. tfile->tun = tun;
  132. tun->tfile = tfile;
  133. dev_hold(tun->dev);
  134. sock_hold(tun->sk);
  135. atomic_inc(&tfile->count);
  136. out:
  137. netif_tx_unlock_bh(tun->dev);
  138. return err;
  139. }
  140. static void __tun_detach(struct tun_struct *tun)
  141. {
  142. /* Detach from net device */
  143. netif_tx_lock_bh(tun->dev);
  144. tun->tfile = NULL;
  145. netif_tx_unlock_bh(tun->dev);
  146. /* Drop read queue */
  147. skb_queue_purge(&tun->readq);
  148. /* Drop the extra count on the net device */
  149. dev_put(tun->dev);
  150. }
  151. static void tun_detach(struct tun_struct *tun)
  152. {
  153. rtnl_lock();
  154. __tun_detach(tun);
  155. rtnl_unlock();
  156. }
  157. static struct tun_struct *__tun_get(struct tun_file *tfile)
  158. {
  159. struct tun_struct *tun = NULL;
  160. if (atomic_inc_not_zero(&tfile->count))
  161. tun = tfile->tun;
  162. return tun;
  163. }
  164. static struct tun_struct *tun_get(struct file *file)
  165. {
  166. return __tun_get(file->private_data);
  167. }
  168. static void tun_put(struct tun_struct *tun)
  169. {
  170. struct tun_file *tfile = tun->tfile;
  171. if (atomic_dec_and_test(&tfile->count))
  172. tun_detach(tfile->tun);
  173. }
  174. /* TAP filterting */
  175. static void addr_hash_set(u32 *mask, const u8 *addr)
  176. {
  177. int n = ether_crc(ETH_ALEN, addr) >> 26;
  178. mask[n >> 5] |= (1 << (n & 31));
  179. }
  180. static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
  181. {
  182. int n = ether_crc(ETH_ALEN, addr) >> 26;
  183. return mask[n >> 5] & (1 << (n & 31));
  184. }
  185. static int update_filter(struct tap_filter *filter, void __user *arg)
  186. {
  187. struct { u8 u[ETH_ALEN]; } *addr;
  188. struct tun_filter uf;
  189. int err, alen, n, nexact;
  190. if (copy_from_user(&uf, arg, sizeof(uf)))
  191. return -EFAULT;
  192. if (!uf.count) {
  193. /* Disabled */
  194. filter->count = 0;
  195. return 0;
  196. }
  197. alen = ETH_ALEN * uf.count;
  198. addr = kmalloc(alen, GFP_KERNEL);
  199. if (!addr)
  200. return -ENOMEM;
  201. if (copy_from_user(addr, arg + sizeof(uf), alen)) {
  202. err = -EFAULT;
  203. goto done;
  204. }
  205. /* The filter is updated without holding any locks. Which is
  206. * perfectly safe. We disable it first and in the worst
  207. * case we'll accept a few undesired packets. */
  208. filter->count = 0;
  209. wmb();
  210. /* Use first set of addresses as an exact filter */
  211. for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
  212. memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
  213. nexact = n;
  214. /* Remaining multicast addresses are hashed,
  215. * unicast will leave the filter disabled. */
  216. memset(filter->mask, 0, sizeof(filter->mask));
  217. for (; n < uf.count; n++) {
  218. if (!is_multicast_ether_addr(addr[n].u)) {
  219. err = 0; /* no filter */
  220. goto done;
  221. }
  222. addr_hash_set(filter->mask, addr[n].u);
  223. }
  224. /* For ALLMULTI just set the mask to all ones.
  225. * This overrides the mask populated above. */
  226. if ((uf.flags & TUN_FLT_ALLMULTI))
  227. memset(filter->mask, ~0, sizeof(filter->mask));
  228. /* Now enable the filter */
  229. wmb();
  230. filter->count = nexact;
  231. /* Return the number of exact filters */
  232. err = nexact;
  233. done:
  234. kfree(addr);
  235. return err;
  236. }
  237. /* Returns: 0 - drop, !=0 - accept */
  238. static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
  239. {
  240. /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
  241. * at this point. */
  242. struct ethhdr *eh = (struct ethhdr *) skb->data;
  243. int i;
  244. /* Exact match */
  245. for (i = 0; i < filter->count; i++)
  246. if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
  247. return 1;
  248. /* Inexact match (multicast only) */
  249. if (is_multicast_ether_addr(eh->h_dest))
  250. return addr_hash_test(filter->mask, eh->h_dest);
  251. return 0;
  252. }
  253. /*
  254. * Checks whether the packet is accepted or not.
  255. * Returns: 0 - drop, !=0 - accept
  256. */
  257. static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
  258. {
  259. if (!filter->count)
  260. return 1;
  261. return run_filter(filter, skb);
  262. }
  263. /* Network device part of the driver */
  264. static const struct ethtool_ops tun_ethtool_ops;
  265. /* Net device detach from fd. */
  266. static void tun_net_uninit(struct net_device *dev)
  267. {
  268. struct tun_struct *tun = netdev_priv(dev);
  269. struct tun_file *tfile = tun->tfile;
  270. /* Inform the methods they need to stop using the dev.
  271. */
  272. if (tfile) {
  273. wake_up_all(&tun->socket.wait);
  274. if (atomic_dec_and_test(&tfile->count))
  275. __tun_detach(tun);
  276. }
  277. }
  278. static void tun_free_netdev(struct net_device *dev)
  279. {
  280. struct tun_struct *tun = netdev_priv(dev);
  281. sock_put(tun->sk);
  282. }
  283. /* Net device open. */
  284. static int tun_net_open(struct net_device *dev)
  285. {
  286. netif_start_queue(dev);
  287. return 0;
  288. }
  289. /* Net device close. */
  290. static int tun_net_close(struct net_device *dev)
  291. {
  292. netif_stop_queue(dev);
  293. return 0;
  294. }
  295. /* Net device start xmit */
  296. static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
  297. {
  298. struct tun_struct *tun = netdev_priv(dev);
  299. DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
  300. /* Drop packet if interface is not attached */
  301. if (!tun->tfile)
  302. goto drop;
  303. /* Drop if the filter does not like it.
  304. * This is a noop if the filter is disabled.
  305. * Filter can be enabled only for the TAP devices. */
  306. if (!check_filter(&tun->txflt, skb))
  307. goto drop;
  308. if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
  309. if (!(tun->flags & TUN_ONE_QUEUE)) {
  310. /* Normal queueing mode. */
  311. /* Packet scheduler handles dropping of further packets. */
  312. netif_stop_queue(dev);
  313. /* We won't see all dropped packets individually, so overrun
  314. * error is more appropriate. */
  315. dev->stats.tx_fifo_errors++;
  316. } else {
  317. /* Single queue mode.
  318. * Driver handles dropping of all packets itself. */
  319. goto drop;
  320. }
  321. }
  322. /* Enqueue packet */
  323. skb_queue_tail(&tun->readq, skb);
  324. dev->trans_start = jiffies;
  325. /* Notify and wake up reader process */
  326. if (tun->flags & TUN_FASYNC)
  327. kill_fasync(&tun->fasync, SIGIO, POLL_IN);
  328. wake_up_interruptible(&tun->socket.wait);
  329. return NETDEV_TX_OK;
  330. drop:
  331. dev->stats.tx_dropped++;
  332. kfree_skb(skb);
  333. return NETDEV_TX_OK;
  334. }
  335. static void tun_net_mclist(struct net_device *dev)
  336. {
  337. /*
  338. * This callback is supposed to deal with mc filter in
  339. * _rx_ path and has nothing to do with the _tx_ path.
  340. * In rx path we always accept everything userspace gives us.
  341. */
  342. return;
  343. }
  344. #define MIN_MTU 68
  345. #define MAX_MTU 65535
  346. static int
  347. tun_net_change_mtu(struct net_device *dev, int new_mtu)
  348. {
  349. if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
  350. return -EINVAL;
  351. dev->mtu = new_mtu;
  352. return 0;
  353. }
  354. static const struct net_device_ops tun_netdev_ops = {
  355. .ndo_uninit = tun_net_uninit,
  356. .ndo_open = tun_net_open,
  357. .ndo_stop = tun_net_close,
  358. .ndo_start_xmit = tun_net_xmit,
  359. .ndo_change_mtu = tun_net_change_mtu,
  360. };
  361. static const struct net_device_ops tap_netdev_ops = {
  362. .ndo_uninit = tun_net_uninit,
  363. .ndo_open = tun_net_open,
  364. .ndo_stop = tun_net_close,
  365. .ndo_start_xmit = tun_net_xmit,
  366. .ndo_change_mtu = tun_net_change_mtu,
  367. .ndo_set_multicast_list = tun_net_mclist,
  368. .ndo_set_mac_address = eth_mac_addr,
  369. .ndo_validate_addr = eth_validate_addr,
  370. };
  371. /* Initialize net device. */
  372. static void tun_net_init(struct net_device *dev)
  373. {
  374. struct tun_struct *tun = netdev_priv(dev);
  375. switch (tun->flags & TUN_TYPE_MASK) {
  376. case TUN_TUN_DEV:
  377. dev->netdev_ops = &tun_netdev_ops;
  378. /* Point-to-Point TUN Device */
  379. dev->hard_header_len = 0;
  380. dev->addr_len = 0;
  381. dev->mtu = 1500;
  382. /* Zero header length */
  383. dev->type = ARPHRD_NONE;
  384. dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
  385. dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
  386. break;
  387. case TUN_TAP_DEV:
  388. dev->netdev_ops = &tap_netdev_ops;
  389. /* Ethernet TAP Device */
  390. ether_setup(dev);
  391. random_ether_addr(dev->dev_addr);
  392. dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */
  393. break;
  394. }
  395. }
  396. /* Character device part */
  397. /* Poll */
  398. static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
  399. {
  400. struct tun_file *tfile = file->private_data;
  401. struct tun_struct *tun = __tun_get(tfile);
  402. struct sock *sk;
  403. unsigned int mask = 0;
  404. if (!tun)
  405. return POLLERR;
  406. sk = tun->sk;
  407. DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
  408. poll_wait(file, &tun->socket.wait, wait);
  409. if (!skb_queue_empty(&tun->readq))
  410. mask |= POLLIN | POLLRDNORM;
  411. if (sock_writeable(sk) ||
  412. (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
  413. sock_writeable(sk)))
  414. mask |= POLLOUT | POLLWRNORM;
  415. if (tun->dev->reg_state != NETREG_REGISTERED)
  416. mask = POLLERR;
  417. tun_put(tun);
  418. return mask;
  419. }
  420. /* prepad is the amount to reserve at front. len is length after that.
  421. * linear is a hint as to how much to copy (usually headers). */
  422. static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun,
  423. size_t prepad, size_t len,
  424. size_t linear, int noblock)
  425. {
  426. struct sock *sk = tun->sk;
  427. struct sk_buff *skb;
  428. int err;
  429. /* Under a page? Don't bother with paged skb. */
  430. if (prepad + len < PAGE_SIZE || !linear)
  431. linear = len;
  432. skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
  433. &err);
  434. if (!skb)
  435. return ERR_PTR(err);
  436. skb_reserve(skb, prepad);
  437. skb_put(skb, linear);
  438. skb->data_len = len - linear;
  439. skb->len += len - linear;
  440. return skb;
  441. }
  442. /* Get packet from user space buffer */
  443. static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
  444. const struct iovec *iv, size_t count,
  445. int noblock)
  446. {
  447. struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
  448. struct sk_buff *skb;
  449. size_t len = count, align = 0;
  450. struct virtio_net_hdr gso = { 0 };
  451. int offset = 0;
  452. if (!(tun->flags & TUN_NO_PI)) {
  453. if ((len -= sizeof(pi)) > count)
  454. return -EINVAL;
  455. if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi)))
  456. return -EFAULT;
  457. offset += sizeof(pi);
  458. }
  459. if (tun->flags & TUN_VNET_HDR) {
  460. if ((len -= sizeof(gso)) > count)
  461. return -EINVAL;
  462. if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso)))
  463. return -EFAULT;
  464. if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
  465. gso.csum_start + gso.csum_offset + 2 > gso.hdr_len)
  466. gso.hdr_len = gso.csum_start + gso.csum_offset + 2;
  467. if (gso.hdr_len > len)
  468. return -EINVAL;
  469. offset += sizeof(gso);
  470. }
  471. if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
  472. align = NET_IP_ALIGN;
  473. if (unlikely(len < ETH_HLEN ||
  474. (gso.hdr_len && gso.hdr_len < ETH_HLEN)))
  475. return -EINVAL;
  476. }
  477. skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock);
  478. if (IS_ERR(skb)) {
  479. if (PTR_ERR(skb) != -EAGAIN)
  480. tun->dev->stats.rx_dropped++;
  481. return PTR_ERR(skb);
  482. }
  483. if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) {
  484. tun->dev->stats.rx_dropped++;
  485. kfree_skb(skb);
  486. return -EFAULT;
  487. }
  488. if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
  489. if (!skb_partial_csum_set(skb, gso.csum_start,
  490. gso.csum_offset)) {
  491. tun->dev->stats.rx_frame_errors++;
  492. kfree_skb(skb);
  493. return -EINVAL;
  494. }
  495. } else if (tun->flags & TUN_NOCHECKSUM)
  496. skb->ip_summed = CHECKSUM_UNNECESSARY;
  497. switch (tun->flags & TUN_TYPE_MASK) {
  498. case TUN_TUN_DEV:
  499. if (tun->flags & TUN_NO_PI) {
  500. switch (skb->data[0] & 0xf0) {
  501. case 0x40:
  502. pi.proto = htons(ETH_P_IP);
  503. break;
  504. case 0x60:
  505. pi.proto = htons(ETH_P_IPV6);
  506. break;
  507. default:
  508. tun->dev->stats.rx_dropped++;
  509. kfree_skb(skb);
  510. return -EINVAL;
  511. }
  512. }
  513. skb_reset_mac_header(skb);
  514. skb->protocol = pi.proto;
  515. skb->dev = tun->dev;
  516. break;
  517. case TUN_TAP_DEV:
  518. skb->protocol = eth_type_trans(skb, tun->dev);
  519. break;
  520. };
  521. if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
  522. pr_debug("GSO!\n");
  523. switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
  524. case VIRTIO_NET_HDR_GSO_TCPV4:
  525. skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
  526. break;
  527. case VIRTIO_NET_HDR_GSO_TCPV6:
  528. skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
  529. break;
  530. default:
  531. tun->dev->stats.rx_frame_errors++;
  532. kfree_skb(skb);
  533. return -EINVAL;
  534. }
  535. if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
  536. skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
  537. skb_shinfo(skb)->gso_size = gso.gso_size;
  538. if (skb_shinfo(skb)->gso_size == 0) {
  539. tun->dev->stats.rx_frame_errors++;
  540. kfree_skb(skb);
  541. return -EINVAL;
  542. }
  543. /* Header must be checked, and gso_segs computed. */
  544. skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
  545. skb_shinfo(skb)->gso_segs = 0;
  546. }
  547. netif_rx_ni(skb);
  548. tun->dev->stats.rx_packets++;
  549. tun->dev->stats.rx_bytes += len;
  550. return count;
  551. }
  552. static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
  553. unsigned long count, loff_t pos)
  554. {
  555. struct file *file = iocb->ki_filp;
  556. struct tun_struct *tun = tun_get(file);
  557. ssize_t result;
  558. if (!tun)
  559. return -EBADFD;
  560. DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
  561. result = tun_get_user(tun, iv, iov_length(iv, count),
  562. file->f_flags & O_NONBLOCK);
  563. tun_put(tun);
  564. return result;
  565. }
  566. /* Put packet to the user space buffer */
  567. static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
  568. struct sk_buff *skb,
  569. const struct iovec *iv, int len)
  570. {
  571. struct tun_pi pi = { 0, skb->protocol };
  572. ssize_t total = 0;
  573. if (!(tun->flags & TUN_NO_PI)) {
  574. if ((len -= sizeof(pi)) < 0)
  575. return -EINVAL;
  576. if (len < skb->len) {
  577. /* Packet will be striped */
  578. pi.flags |= TUN_PKT_STRIP;
  579. }
  580. if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi)))
  581. return -EFAULT;
  582. total += sizeof(pi);
  583. }
  584. if (tun->flags & TUN_VNET_HDR) {
  585. struct virtio_net_hdr gso = { 0 }; /* no info leak */
  586. if ((len -= sizeof(gso)) < 0)
  587. return -EINVAL;
  588. if (skb_is_gso(skb)) {
  589. struct skb_shared_info *sinfo = skb_shinfo(skb);
  590. /* This is a hint as to how much should be linear. */
  591. gso.hdr_len = skb_headlen(skb);
  592. gso.gso_size = sinfo->gso_size;
  593. if (sinfo->gso_type & SKB_GSO_TCPV4)
  594. gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
  595. else if (sinfo->gso_type & SKB_GSO_TCPV6)
  596. gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
  597. else
  598. BUG();
  599. if (sinfo->gso_type & SKB_GSO_TCP_ECN)
  600. gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
  601. } else
  602. gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
  603. if (skb->ip_summed == CHECKSUM_PARTIAL) {
  604. gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
  605. gso.csum_start = skb->csum_start - skb_headroom(skb);
  606. gso.csum_offset = skb->csum_offset;
  607. } /* else everything is zero */
  608. if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
  609. sizeof(gso))))
  610. return -EFAULT;
  611. total += sizeof(gso);
  612. }
  613. len = min_t(int, skb->len, len);
  614. skb_copy_datagram_const_iovec(skb, 0, iv, total, len);
  615. total += len;
  616. tun->dev->stats.tx_packets++;
  617. tun->dev->stats.tx_bytes += len;
  618. return total;
  619. }
  620. static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
  621. unsigned long count, loff_t pos)
  622. {
  623. struct file *file = iocb->ki_filp;
  624. struct tun_file *tfile = file->private_data;
  625. struct tun_struct *tun = __tun_get(tfile);
  626. DECLARE_WAITQUEUE(wait, current);
  627. struct sk_buff *skb;
  628. ssize_t len, ret = 0;
  629. if (!tun)
  630. return -EBADFD;
  631. DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
  632. len = iov_length(iv, count);
  633. if (len < 0) {
  634. ret = -EINVAL;
  635. goto out;
  636. }
  637. add_wait_queue(&tun->socket.wait, &wait);
  638. while (len) {
  639. current->state = TASK_INTERRUPTIBLE;
  640. /* Read frames from the queue */
  641. if (!(skb=skb_dequeue(&tun->readq))) {
  642. if (file->f_flags & O_NONBLOCK) {
  643. ret = -EAGAIN;
  644. break;
  645. }
  646. if (signal_pending(current)) {
  647. ret = -ERESTARTSYS;
  648. break;
  649. }
  650. if (tun->dev->reg_state != NETREG_REGISTERED) {
  651. ret = -EIO;
  652. break;
  653. }
  654. /* Nothing to read, let's sleep */
  655. schedule();
  656. continue;
  657. }
  658. netif_wake_queue(tun->dev);
  659. ret = tun_put_user(tun, skb, iv, len);
  660. kfree_skb(skb);
  661. break;
  662. }
  663. current->state = TASK_RUNNING;
  664. remove_wait_queue(&tun->socket.wait, &wait);
  665. out:
  666. tun_put(tun);
  667. return ret;
  668. }
  669. static void tun_setup(struct net_device *dev)
  670. {
  671. struct tun_struct *tun = netdev_priv(dev);
  672. skb_queue_head_init(&tun->readq);
  673. tun->owner = -1;
  674. tun->group = -1;
  675. dev->ethtool_ops = &tun_ethtool_ops;
  676. dev->destructor = tun_free_netdev;
  677. }
  678. /* Trivial set of netlink ops to allow deleting tun or tap
  679. * device with netlink.
  680. */
  681. static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
  682. {
  683. return -EINVAL;
  684. }
  685. static struct rtnl_link_ops tun_link_ops __read_mostly = {
  686. .kind = DRV_NAME,
  687. .priv_size = sizeof(struct tun_struct),
  688. .setup = tun_setup,
  689. .validate = tun_validate,
  690. };
  691. static void tun_sock_write_space(struct sock *sk)
  692. {
  693. struct tun_struct *tun;
  694. if (!sock_writeable(sk))
  695. return;
  696. if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags))
  697. return;
  698. if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
  699. wake_up_interruptible_sync(sk->sk_sleep);
  700. tun = container_of(sk, struct tun_sock, sk)->tun;
  701. kill_fasync(&tun->fasync, SIGIO, POLL_OUT);
  702. }
  703. static void tun_sock_destruct(struct sock *sk)
  704. {
  705. free_netdev(container_of(sk, struct tun_sock, sk)->tun->dev);
  706. }
  707. static struct proto tun_proto = {
  708. .name = "tun",
  709. .owner = THIS_MODULE,
  710. .obj_size = sizeof(struct tun_sock),
  711. };
  712. static int tun_flags(struct tun_struct *tun)
  713. {
  714. int flags = 0;
  715. if (tun->flags & TUN_TUN_DEV)
  716. flags |= IFF_TUN;
  717. else
  718. flags |= IFF_TAP;
  719. if (tun->flags & TUN_NO_PI)
  720. flags |= IFF_NO_PI;
  721. if (tun->flags & TUN_ONE_QUEUE)
  722. flags |= IFF_ONE_QUEUE;
  723. if (tun->flags & TUN_VNET_HDR)
  724. flags |= IFF_VNET_HDR;
  725. return flags;
  726. }
  727. static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr,
  728. char *buf)
  729. {
  730. struct tun_struct *tun = netdev_priv(to_net_dev(dev));
  731. return sprintf(buf, "0x%x\n", tun_flags(tun));
  732. }
  733. static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr,
  734. char *buf)
  735. {
  736. struct tun_struct *tun = netdev_priv(to_net_dev(dev));
  737. return sprintf(buf, "%d\n", tun->owner);
  738. }
  739. static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
  740. char *buf)
  741. {
  742. struct tun_struct *tun = netdev_priv(to_net_dev(dev));
  743. return sprintf(buf, "%d\n", tun->group);
  744. }
  745. static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
  746. static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL);
  747. static DEVICE_ATTR(group, 0444, tun_show_group, NULL);
  748. static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
  749. {
  750. struct sock *sk;
  751. struct tun_struct *tun;
  752. struct net_device *dev;
  753. int err;
  754. dev = __dev_get_by_name(net, ifr->ifr_name);
  755. if (dev) {
  756. if (ifr->ifr_flags & IFF_TUN_EXCL)
  757. return -EBUSY;
  758. if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
  759. tun = netdev_priv(dev);
  760. else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
  761. tun = netdev_priv(dev);
  762. else
  763. return -EINVAL;
  764. err = tun_attach(tun, file);
  765. if (err < 0)
  766. return err;
  767. }
  768. else {
  769. char *name;
  770. unsigned long flags = 0;
  771. err = -EINVAL;
  772. if (!capable(CAP_NET_ADMIN))
  773. return -EPERM;
  774. /* Set dev type */
  775. if (ifr->ifr_flags & IFF_TUN) {
  776. /* TUN device */
  777. flags |= TUN_TUN_DEV;
  778. name = "tun%d";
  779. } else if (ifr->ifr_flags & IFF_TAP) {
  780. /* TAP device */
  781. flags |= TUN_TAP_DEV;
  782. name = "tap%d";
  783. } else
  784. goto failed;
  785. if (*ifr->ifr_name)
  786. name = ifr->ifr_name;
  787. dev = alloc_netdev(sizeof(struct tun_struct), name,
  788. tun_setup);
  789. if (!dev)
  790. return -ENOMEM;
  791. dev_net_set(dev, net);
  792. dev->rtnl_link_ops = &tun_link_ops;
  793. tun = netdev_priv(dev);
  794. tun->dev = dev;
  795. tun->flags = flags;
  796. tun->txflt.count = 0;
  797. err = -ENOMEM;
  798. sk = sk_alloc(net, AF_UNSPEC, GFP_KERNEL, &tun_proto);
  799. if (!sk)
  800. goto err_free_dev;
  801. init_waitqueue_head(&tun->socket.wait);
  802. sock_init_data(&tun->socket, sk);
  803. sk->sk_write_space = tun_sock_write_space;
  804. sk->sk_sndbuf = INT_MAX;
  805. tun->sk = sk;
  806. container_of(sk, struct tun_sock, sk)->tun = tun;
  807. tun_net_init(dev);
  808. if (strchr(dev->name, '%')) {
  809. err = dev_alloc_name(dev, dev->name);
  810. if (err < 0)
  811. goto err_free_sk;
  812. }
  813. err = register_netdevice(tun->dev);
  814. if (err < 0)
  815. goto err_free_sk;
  816. if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) ||
  817. device_create_file(&tun->dev->dev, &dev_attr_owner) ||
  818. device_create_file(&tun->dev->dev, &dev_attr_group))
  819. printk(KERN_ERR "Failed to create tun sysfs files\n");
  820. sk->sk_destruct = tun_sock_destruct;
  821. err = tun_attach(tun, file);
  822. if (err < 0)
  823. goto failed;
  824. }
  825. DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
  826. if (ifr->ifr_flags & IFF_NO_PI)
  827. tun->flags |= TUN_NO_PI;
  828. else
  829. tun->flags &= ~TUN_NO_PI;
  830. if (ifr->ifr_flags & IFF_ONE_QUEUE)
  831. tun->flags |= TUN_ONE_QUEUE;
  832. else
  833. tun->flags &= ~TUN_ONE_QUEUE;
  834. if (ifr->ifr_flags & IFF_VNET_HDR)
  835. tun->flags |= TUN_VNET_HDR;
  836. else
  837. tun->flags &= ~TUN_VNET_HDR;
  838. /* Make sure persistent devices do not get stuck in
  839. * xoff state.
  840. */
  841. if (netif_running(tun->dev))
  842. netif_wake_queue(tun->dev);
  843. strcpy(ifr->ifr_name, tun->dev->name);
  844. return 0;
  845. err_free_sk:
  846. sock_put(sk);
  847. err_free_dev:
  848. free_netdev(dev);
  849. failed:
  850. return err;
  851. }
  852. static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr)
  853. {
  854. struct tun_struct *tun = tun_get(file);
  855. if (!tun)
  856. return -EBADFD;
  857. DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
  858. strcpy(ifr->ifr_name, tun->dev->name);
  859. ifr->ifr_flags = tun_flags(tun);
  860. tun_put(tun);
  861. return 0;
  862. }
  863. /* This is like a cut-down ethtool ops, except done via tun fd so no
  864. * privs required. */
  865. static int set_offload(struct net_device *dev, unsigned long arg)
  866. {
  867. unsigned int old_features, features;
  868. old_features = dev->features;
  869. /* Unset features, set them as we chew on the arg. */
  870. features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
  871. |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6));
  872. if (arg & TUN_F_CSUM) {
  873. features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
  874. arg &= ~TUN_F_CSUM;
  875. if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
  876. if (arg & TUN_F_TSO_ECN) {
  877. features |= NETIF_F_TSO_ECN;
  878. arg &= ~TUN_F_TSO_ECN;
  879. }
  880. if (arg & TUN_F_TSO4)
  881. features |= NETIF_F_TSO;
  882. if (arg & TUN_F_TSO6)
  883. features |= NETIF_F_TSO6;
  884. arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
  885. }
  886. }
  887. /* This gives the user a way to test for new features in future by
  888. * trying to set them. */
  889. if (arg)
  890. return -EINVAL;
  891. dev->features = features;
  892. if (old_features != dev->features)
  893. netdev_features_change(dev);
  894. return 0;
  895. }
  896. static int tun_chr_ioctl(struct inode *inode, struct file *file,
  897. unsigned int cmd, unsigned long arg)
  898. {
  899. struct tun_file *tfile = file->private_data;
  900. struct tun_struct *tun;
  901. void __user* argp = (void __user*)arg;
  902. struct ifreq ifr;
  903. int sndbuf;
  904. int ret;
  905. if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
  906. if (copy_from_user(&ifr, argp, sizeof ifr))
  907. return -EFAULT;
  908. if (cmd == TUNGETFEATURES) {
  909. /* Currently this just means: "what IFF flags are valid?".
  910. * This is needed because we never checked for invalid flags on
  911. * TUNSETIFF. */
  912. return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
  913. IFF_VNET_HDR,
  914. (unsigned int __user*)argp);
  915. }
  916. tun = __tun_get(tfile);
  917. if (cmd == TUNSETIFF && !tun) {
  918. int err;
  919. ifr.ifr_name[IFNAMSIZ-1] = '\0';
  920. rtnl_lock();
  921. err = tun_set_iff(tfile->net, file, &ifr);
  922. rtnl_unlock();
  923. if (err)
  924. return err;
  925. if (copy_to_user(argp, &ifr, sizeof(ifr)))
  926. return -EFAULT;
  927. return 0;
  928. }
  929. if (!tun)
  930. return -EBADFD;
  931. DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
  932. ret = 0;
  933. switch (cmd) {
  934. case TUNGETIFF:
  935. ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr);
  936. if (ret)
  937. break;
  938. if (copy_to_user(argp, &ifr, sizeof(ifr)))
  939. ret = -EFAULT;
  940. break;
  941. case TUNSETNOCSUM:
  942. /* Disable/Enable checksum */
  943. if (arg)
  944. tun->flags |= TUN_NOCHECKSUM;
  945. else
  946. tun->flags &= ~TUN_NOCHECKSUM;
  947. DBG(KERN_INFO "%s: checksum %s\n",
  948. tun->dev->name, arg ? "disabled" : "enabled");
  949. break;
  950. case TUNSETPERSIST:
  951. /* Disable/Enable persist mode */
  952. if (arg)
  953. tun->flags |= TUN_PERSIST;
  954. else
  955. tun->flags &= ~TUN_PERSIST;
  956. DBG(KERN_INFO "%s: persist %s\n",
  957. tun->dev->name, arg ? "enabled" : "disabled");
  958. break;
  959. case TUNSETOWNER:
  960. /* Set owner of the device */
  961. tun->owner = (uid_t) arg;
  962. DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
  963. break;
  964. case TUNSETGROUP:
  965. /* Set group of the device */
  966. tun->group= (gid_t) arg;
  967. DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
  968. break;
  969. case TUNSETLINK:
  970. /* Only allow setting the type when the interface is down */
  971. rtnl_lock();
  972. if (tun->dev->flags & IFF_UP) {
  973. DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
  974. tun->dev->name);
  975. ret = -EBUSY;
  976. } else {
  977. tun->dev->type = (int) arg;
  978. DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
  979. ret = 0;
  980. }
  981. rtnl_unlock();
  982. break;
  983. #ifdef TUN_DEBUG
  984. case TUNSETDEBUG:
  985. tun->debug = arg;
  986. break;
  987. #endif
  988. case TUNSETOFFLOAD:
  989. rtnl_lock();
  990. ret = set_offload(tun->dev, arg);
  991. rtnl_unlock();
  992. break;
  993. case TUNSETTXFILTER:
  994. /* Can be set only for TAPs */
  995. ret = -EINVAL;
  996. if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
  997. break;
  998. rtnl_lock();
  999. ret = update_filter(&tun->txflt, (void __user *)arg);
  1000. rtnl_unlock();
  1001. break;
  1002. case SIOCGIFHWADDR:
  1003. /* Get hw addres */
  1004. memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
  1005. ifr.ifr_hwaddr.sa_family = tun->dev->type;
  1006. if (copy_to_user(argp, &ifr, sizeof ifr))
  1007. ret = -EFAULT;
  1008. break;
  1009. case SIOCSIFHWADDR:
  1010. /* Set hw address */
  1011. DBG(KERN_DEBUG "%s: set hw address: %pM\n",
  1012. tun->dev->name, ifr.ifr_hwaddr.sa_data);
  1013. rtnl_lock();
  1014. ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
  1015. rtnl_unlock();
  1016. break;
  1017. case TUNGETSNDBUF:
  1018. sndbuf = tun->sk->sk_sndbuf;
  1019. if (copy_to_user(argp, &sndbuf, sizeof(sndbuf)))
  1020. ret = -EFAULT;
  1021. break;
  1022. case TUNSETSNDBUF:
  1023. if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) {
  1024. ret = -EFAULT;
  1025. break;
  1026. }
  1027. tun->sk->sk_sndbuf = sndbuf;
  1028. break;
  1029. default:
  1030. ret = -EINVAL;
  1031. break;
  1032. };
  1033. tun_put(tun);
  1034. return ret;
  1035. }
  1036. static int tun_chr_fasync(int fd, struct file *file, int on)
  1037. {
  1038. struct tun_struct *tun = tun_get(file);
  1039. int ret;
  1040. if (!tun)
  1041. return -EBADFD;
  1042. DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
  1043. lock_kernel();
  1044. if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
  1045. goto out;
  1046. if (on) {
  1047. ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
  1048. if (ret)
  1049. goto out;
  1050. tun->flags |= TUN_FASYNC;
  1051. } else
  1052. tun->flags &= ~TUN_FASYNC;
  1053. ret = 0;
  1054. out:
  1055. unlock_kernel();
  1056. tun_put(tun);
  1057. return ret;
  1058. }
  1059. static int tun_chr_open(struct inode *inode, struct file * file)
  1060. {
  1061. struct tun_file *tfile;
  1062. cycle_kernel_lock();
  1063. DBG1(KERN_INFO "tunX: tun_chr_open\n");
  1064. tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
  1065. if (!tfile)
  1066. return -ENOMEM;
  1067. atomic_set(&tfile->count, 0);
  1068. tfile->tun = NULL;
  1069. tfile->net = get_net(current->nsproxy->net_ns);
  1070. file->private_data = tfile;
  1071. return 0;
  1072. }
  1073. static int tun_chr_close(struct inode *inode, struct file *file)
  1074. {
  1075. struct tun_file *tfile = file->private_data;
  1076. struct tun_struct *tun;
  1077. tun = __tun_get(tfile);
  1078. if (tun) {
  1079. struct net_device *dev = tun->dev;
  1080. DBG(KERN_INFO "%s: tun_chr_close\n", dev->name);
  1081. __tun_detach(tun);
  1082. /* If desireable, unregister the netdevice. */
  1083. if (!(tun->flags & TUN_PERSIST)) {
  1084. rtnl_lock();
  1085. if (dev->reg_state == NETREG_REGISTERED)
  1086. unregister_netdevice(dev);
  1087. rtnl_unlock();
  1088. }
  1089. }
  1090. tun = tfile->tun;
  1091. if (tun)
  1092. sock_put(tun->sk);
  1093. put_net(tfile->net);
  1094. kfree(tfile);
  1095. return 0;
  1096. }
  1097. static const struct file_operations tun_fops = {
  1098. .owner = THIS_MODULE,
  1099. .llseek = no_llseek,
  1100. .read = do_sync_read,
  1101. .aio_read = tun_chr_aio_read,
  1102. .write = do_sync_write,
  1103. .aio_write = tun_chr_aio_write,
  1104. .poll = tun_chr_poll,
  1105. .ioctl = tun_chr_ioctl,
  1106. .open = tun_chr_open,
  1107. .release = tun_chr_close,
  1108. .fasync = tun_chr_fasync
  1109. };
  1110. static struct miscdevice tun_miscdev = {
  1111. .minor = TUN_MINOR,
  1112. .name = "tun",
  1113. .devnode = "net/tun",
  1114. .fops = &tun_fops,
  1115. };
  1116. /* ethtool interface */
  1117. static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
  1118. {
  1119. cmd->supported = 0;
  1120. cmd->advertising = 0;
  1121. cmd->speed = SPEED_10;
  1122. cmd->duplex = DUPLEX_FULL;
  1123. cmd->port = PORT_TP;
  1124. cmd->phy_address = 0;
  1125. cmd->transceiver = XCVR_INTERNAL;
  1126. cmd->autoneg = AUTONEG_DISABLE;
  1127. cmd->maxtxpkt = 0;
  1128. cmd->maxrxpkt = 0;
  1129. return 0;
  1130. }
  1131. static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
  1132. {
  1133. struct tun_struct *tun = netdev_priv(dev);
  1134. strcpy(info->driver, DRV_NAME);
  1135. strcpy(info->version, DRV_VERSION);
  1136. strcpy(info->fw_version, "N/A");
  1137. switch (tun->flags & TUN_TYPE_MASK) {
  1138. case TUN_TUN_DEV:
  1139. strcpy(info->bus_info, "tun");
  1140. break;
  1141. case TUN_TAP_DEV:
  1142. strcpy(info->bus_info, "tap");
  1143. break;
  1144. }
  1145. }
  1146. static u32 tun_get_msglevel(struct net_device *dev)
  1147. {
  1148. #ifdef TUN_DEBUG
  1149. struct tun_struct *tun = netdev_priv(dev);
  1150. return tun->debug;
  1151. #else
  1152. return -EOPNOTSUPP;
  1153. #endif
  1154. }
  1155. static void tun_set_msglevel(struct net_device *dev, u32 value)
  1156. {
  1157. #ifdef TUN_DEBUG
  1158. struct tun_struct *tun = netdev_priv(dev);
  1159. tun->debug = value;
  1160. #endif
  1161. }
  1162. static u32 tun_get_link(struct net_device *dev)
  1163. {
  1164. struct tun_struct *tun = netdev_priv(dev);
  1165. return !!tun->tfile;
  1166. }
  1167. static u32 tun_get_rx_csum(struct net_device *dev)
  1168. {
  1169. struct tun_struct *tun = netdev_priv(dev);
  1170. return (tun->flags & TUN_NOCHECKSUM) == 0;
  1171. }
  1172. static int tun_set_rx_csum(struct net_device *dev, u32 data)
  1173. {
  1174. struct tun_struct *tun = netdev_priv(dev);
  1175. if (data)
  1176. tun->flags &= ~TUN_NOCHECKSUM;
  1177. else
  1178. tun->flags |= TUN_NOCHECKSUM;
  1179. return 0;
  1180. }
  1181. static const struct ethtool_ops tun_ethtool_ops = {
  1182. .get_settings = tun_get_settings,
  1183. .get_drvinfo = tun_get_drvinfo,
  1184. .get_msglevel = tun_get_msglevel,
  1185. .set_msglevel = tun_set_msglevel,
  1186. .get_link = tun_get_link,
  1187. .get_rx_csum = tun_get_rx_csum,
  1188. .set_rx_csum = tun_set_rx_csum
  1189. };
  1190. static int __init tun_init(void)
  1191. {
  1192. int ret = 0;
  1193. printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
  1194. printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
  1195. ret = rtnl_link_register(&tun_link_ops);
  1196. if (ret) {
  1197. printk(KERN_ERR "tun: Can't register link_ops\n");
  1198. goto err_linkops;
  1199. }
  1200. ret = misc_register(&tun_miscdev);
  1201. if (ret) {
  1202. printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
  1203. goto err_misc;
  1204. }
  1205. return 0;
  1206. err_misc:
  1207. rtnl_link_unregister(&tun_link_ops);
  1208. err_linkops:
  1209. return ret;
  1210. }
  1211. static void tun_cleanup(void)
  1212. {
  1213. misc_deregister(&tun_miscdev);
  1214. rtnl_link_unregister(&tun_link_ops);
  1215. }
  1216. module_init(tun_init);
  1217. module_exit(tun_cleanup);
  1218. MODULE_DESCRIPTION(DRV_DESCRIPTION);
  1219. MODULE_AUTHOR(DRV_COPYRIGHT);
  1220. MODULE_LICENSE("GPL");
  1221. MODULE_ALIAS_MISCDEV(TUN_MINOR);