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 * 21 * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14 22 * Add TUNSETLINK ioctl to set the link encapsulation 23 * 24 * Mark Smith <markzzzsmith@yahoo.com.au> 25 * Use random_ether_addr() for tap MAC address. 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 37 #define DRV_NAME "tun" 38 #define DRV_VERSION "1.6" 39 #define DRV_DESCRIPTION "Universal TUN/TAP device driver" 40 #define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>" 41 42 #include <linux/module.h> 43 #include <linux/errno.h> 44 #include <linux/kernel.h> 45 #include <linux/major.h> 46 #include <linux/slab.h> 47 #include <linux/smp_lock.h> 48 #include <linux/poll.h> 49 #include <linux/fcntl.h> 50 #include <linux/init.h> 51 #include <linux/skbuff.h> 52 #include <linux/netdevice.h> 53 #include <linux/etherdevice.h> 54 #include <linux/miscdevice.h> 55 #include <linux/ethtool.h> 56 #include <linux/rtnetlink.h> 57 #include <linux/if.h> 58 #include <linux/if_arp.h> 59 #include <linux/if_ether.h> 60 #include <linux/if_tun.h> 61 #include <linux/crc32.h> 62 #include <linux/nsproxy.h> 63 #include <linux/virtio_net.h> 64 #include <net/net_namespace.h> 65 #include <net/netns/generic.h> 66 #include <net/rtnetlink.h> 67 #include <net/sock.h> 68 69 #include <asm/system.h> 70 #include <asm/uaccess.h> 71 72 /* Uncomment to enable debugging */ 73 /* #define TUN_DEBUG 1 */ 74 75 #ifdef TUN_DEBUG 76 static int debug; 77 78 #define DBG if(tun->debug)printk 79 #define DBG1 if(debug==2)printk 80 #else 81 #define DBG( a... ) 82 #define DBG1( a... ) 83 #endif 84 85 #define FLT_EXACT_COUNT 8 86 struct tap_filter { 87 unsigned int count; /* Number of addrs. Zero means disabled */ 88 u32 mask[2]; /* Mask of the hashed addrs */ 89 unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN]; 90 }; 91 92 struct tun_file { 93 atomic_t count; 94 struct tun_struct *tun; 95 struct net *net; 96 }; 97 98 struct tun_sock; 99 100 struct tun_struct { 101 struct tun_file *tfile; 102 unsigned int flags; 103 uid_t owner; 104 gid_t group; 105 106 struct sk_buff_head readq; 107 108 struct net_device *dev; 109 struct fasync_struct *fasync; 110 111 struct tap_filter txflt; 112 struct sock *sk; 113 struct socket socket; 114 115 #ifdef TUN_DEBUG 116 int debug; 117 #endif 118 }; 119 120 struct tun_sock { 121 struct sock sk; 122 struct tun_struct *tun; 123 }; 124 125 static inline struct tun_sock *tun_sk(struct sock *sk) 126 { 127 return container_of(sk, struct tun_sock, sk); 128 } 129 130 static int tun_attach(struct tun_struct *tun, struct file *file) 131 { 132 struct tun_file *tfile = file->private_data; 133 const struct cred *cred = current_cred(); 134 int err; 135 136 ASSERT_RTNL(); 137 138 /* Check permissions */ 139 if (((tun->owner != -1 && cred->euid != tun->owner) || 140 (tun->group != -1 && !in_egroup_p(tun->group))) && 141 !capable(CAP_NET_ADMIN)) 142 return -EPERM; 143 144 netif_tx_lock_bh(tun->dev); 145 146 err = -EINVAL; 147 if (tfile->tun) 148 goto out; 149 150 err = -EBUSY; 151 if (tun->tfile) 152 goto out; 153 154 err = 0; 155 tfile->tun = tun; 156 tun->tfile = tfile; 157 dev_hold(tun->dev); 158 sock_hold(tun->sk); 159 atomic_inc(&tfile->count); 160 161 out: 162 netif_tx_unlock_bh(tun->dev); 163 return err; 164 } 165 166 static void __tun_detach(struct tun_struct *tun) 167 { 168 /* Detach from net device */ 169 netif_tx_lock_bh(tun->dev); 170 tun->tfile = NULL; 171 netif_tx_unlock_bh(tun->dev); 172 173 /* Drop read queue */ 174 skb_queue_purge(&tun->readq); 175 176 /* Drop the extra count on the net device */ 177 dev_put(tun->dev); 178 } 179 180 static void tun_detach(struct tun_struct *tun) 181 { 182 rtnl_lock(); 183 __tun_detach(tun); 184 rtnl_unlock(); 185 } 186 187 static struct tun_struct *__tun_get(struct tun_file *tfile) 188 { 189 struct tun_struct *tun = NULL; 190 191 if (atomic_inc_not_zero(&tfile->count)) 192 tun = tfile->tun; 193 194 return tun; 195 } 196 197 static struct tun_struct *tun_get(struct file *file) 198 { 199 return __tun_get(file->private_data); 200 } 201 202 static void tun_put(struct tun_struct *tun) 203 { 204 struct tun_file *tfile = tun->tfile; 205 206 if (atomic_dec_and_test(&tfile->count)) 207 tun_detach(tfile->tun); 208 } 209 210 /* TAP filterting */ 211 static void addr_hash_set(u32 *mask, const u8 *addr) 212 { 213 int n = ether_crc(ETH_ALEN, addr) >> 26; 214 mask[n >> 5] |= (1 << (n & 31)); 215 } 216 217 static unsigned int addr_hash_test(const u32 *mask, const u8 *addr) 218 { 219 int n = ether_crc(ETH_ALEN, addr) >> 26; 220 return mask[n >> 5] & (1 << (n & 31)); 221 } 222 223 static int update_filter(struct tap_filter *filter, void __user *arg) 224 { 225 struct { u8 u[ETH_ALEN]; } *addr; 226 struct tun_filter uf; 227 int err, alen, n, nexact; 228 229 if (copy_from_user(&uf, arg, sizeof(uf))) 230 return -EFAULT; 231 232 if (!uf.count) { 233 /* Disabled */ 234 filter->count = 0; 235 return 0; 236 } 237 238 alen = ETH_ALEN * uf.count; 239 addr = kmalloc(alen, GFP_KERNEL); 240 if (!addr) 241 return -ENOMEM; 242 243 if (copy_from_user(addr, arg + sizeof(uf), alen)) { 244 err = -EFAULT; 245 goto done; 246 } 247 248 /* The filter is updated without holding any locks. Which is 249 * perfectly safe. We disable it first and in the worst 250 * case we'll accept a few undesired packets. */ 251 filter->count = 0; 252 wmb(); 253 254 /* Use first set of addresses as an exact filter */ 255 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++) 256 memcpy(filter->addr[n], addr[n].u, ETH_ALEN); 257 258 nexact = n; 259 260 /* Remaining multicast addresses are hashed, 261 * unicast will leave the filter disabled. */ 262 memset(filter->mask, 0, sizeof(filter->mask)); 263 for (; n < uf.count; n++) { 264 if (!is_multicast_ether_addr(addr[n].u)) { 265 err = 0; /* no filter */ 266 goto done; 267 } 268 addr_hash_set(filter->mask, addr[n].u); 269 } 270 271 /* For ALLMULTI just set the mask to all ones. 272 * This overrides the mask populated above. */ 273 if ((uf.flags & TUN_FLT_ALLMULTI)) 274 memset(filter->mask, ~0, sizeof(filter->mask)); 275 276 /* Now enable the filter */ 277 wmb(); 278 filter->count = nexact; 279 280 /* Return the number of exact filters */ 281 err = nexact; 282 283 done: 284 kfree(addr); 285 return err; 286 } 287 288 /* Returns: 0 - drop, !=0 - accept */ 289 static int run_filter(struct tap_filter *filter, const struct sk_buff *skb) 290 { 291 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect 292 * at this point. */ 293 struct ethhdr *eh = (struct ethhdr *) skb->data; 294 int i; 295 296 /* Exact match */ 297 for (i = 0; i < filter->count; i++) 298 if (!compare_ether_addr(eh->h_dest, filter->addr[i])) 299 return 1; 300 301 /* Inexact match (multicast only) */ 302 if (is_multicast_ether_addr(eh->h_dest)) 303 return addr_hash_test(filter->mask, eh->h_dest); 304 305 return 0; 306 } 307 308 /* 309 * Checks whether the packet is accepted or not. 310 * Returns: 0 - drop, !=0 - accept 311 */ 312 static int check_filter(struct tap_filter *filter, const struct sk_buff *skb) 313 { 314 if (!filter->count) 315 return 1; 316 317 return run_filter(filter, skb); 318 } 319 320 /* Network device part of the driver */ 321 322 static const struct ethtool_ops tun_ethtool_ops; 323 324 /* Net device detach from fd. */ 325 static void tun_net_uninit(struct net_device *dev) 326 { 327 struct tun_struct *tun = netdev_priv(dev); 328 struct tun_file *tfile = tun->tfile; 329 330 /* Inform the methods they need to stop using the dev. 331 */ 332 if (tfile) { 333 wake_up_all(&tun->socket.wait); 334 if (atomic_dec_and_test(&tfile->count)) 335 __tun_detach(tun); 336 } 337 } 338 339 static void tun_free_netdev(struct net_device *dev) 340 { 341 struct tun_struct *tun = netdev_priv(dev); 342 343 sock_put(tun->sk); 344 } 345 346 /* Net device open. */ 347 static int tun_net_open(struct net_device *dev) 348 { 349 netif_start_queue(dev); 350 return 0; 351 } 352 353 /* Net device close. */ 354 static int tun_net_close(struct net_device *dev) 355 { 356 netif_stop_queue(dev); 357 return 0; 358 } 359 360 /* Net device start xmit */ 361 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev) 362 { 363 struct tun_struct *tun = netdev_priv(dev); 364 365 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len); 366 367 /* Drop packet if interface is not attached */ 368 if (!tun->tfile) 369 goto drop; 370 371 /* Drop if the filter does not like it. 372 * This is a noop if the filter is disabled. 373 * Filter can be enabled only for the TAP devices. */ 374 if (!check_filter(&tun->txflt, skb)) 375 goto drop; 376 377 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) { 378 if (!(tun->flags & TUN_ONE_QUEUE)) { 379 /* Normal queueing mode. */ 380 /* Packet scheduler handles dropping of further packets. */ 381 netif_stop_queue(dev); 382 383 /* We won't see all dropped packets individually, so overrun 384 * error is more appropriate. */ 385 dev->stats.tx_fifo_errors++; 386 } else { 387 /* Single queue mode. 388 * Driver handles dropping of all packets itself. */ 389 goto drop; 390 } 391 } 392 393 /* Enqueue packet */ 394 skb_queue_tail(&tun->readq, skb); 395 dev->trans_start = jiffies; 396 397 /* Notify and wake up reader process */ 398 if (tun->flags & TUN_FASYNC) 399 kill_fasync(&tun->fasync, SIGIO, POLL_IN); 400 wake_up_interruptible(&tun->socket.wait); 401 return 0; 402 403 drop: 404 dev->stats.tx_dropped++; 405 kfree_skb(skb); 406 return 0; 407 } 408 409 static void tun_net_mclist(struct net_device *dev) 410 { 411 /* 412 * This callback is supposed to deal with mc filter in 413 * _rx_ path and has nothing to do with the _tx_ path. 414 * In rx path we always accept everything userspace gives us. 415 */ 416 return; 417 } 418 419 #define MIN_MTU 68 420 #define MAX_MTU 65535 421 422 static int 423 tun_net_change_mtu(struct net_device *dev, int new_mtu) 424 { 425 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU) 426 return -EINVAL; 427 dev->mtu = new_mtu; 428 return 0; 429 } 430 431 static const struct net_device_ops tun_netdev_ops = { 432 .ndo_uninit = tun_net_uninit, 433 .ndo_open = tun_net_open, 434 .ndo_stop = tun_net_close, 435 .ndo_start_xmit = tun_net_xmit, 436 .ndo_change_mtu = tun_net_change_mtu, 437 }; 438 439 static const struct net_device_ops tap_netdev_ops = { 440 .ndo_uninit = tun_net_uninit, 441 .ndo_open = tun_net_open, 442 .ndo_stop = tun_net_close, 443 .ndo_start_xmit = tun_net_xmit, 444 .ndo_change_mtu = tun_net_change_mtu, 445 .ndo_set_multicast_list = tun_net_mclist, 446 .ndo_set_mac_address = eth_mac_addr, 447 .ndo_validate_addr = eth_validate_addr, 448 }; 449 450 /* Initialize net device. */ 451 static void tun_net_init(struct net_device *dev) 452 { 453 struct tun_struct *tun = netdev_priv(dev); 454 455 switch (tun->flags & TUN_TYPE_MASK) { 456 case TUN_TUN_DEV: 457 dev->netdev_ops = &tun_netdev_ops; 458 459 /* Point-to-Point TUN Device */ 460 dev->hard_header_len = 0; 461 dev->addr_len = 0; 462 dev->mtu = 1500; 463 464 /* Zero header length */ 465 dev->type = ARPHRD_NONE; 466 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; 467 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 468 break; 469 470 case TUN_TAP_DEV: 471 dev->netdev_ops = &tap_netdev_ops; 472 /* Ethernet TAP Device */ 473 ether_setup(dev); 474 475 random_ether_addr(dev->dev_addr); 476 477 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 478 break; 479 } 480 } 481 482 /* Character device part */ 483 484 /* Poll */ 485 static unsigned int tun_chr_poll(struct file *file, poll_table * wait) 486 { 487 struct tun_file *tfile = file->private_data; 488 struct tun_struct *tun = __tun_get(tfile); 489 struct sock *sk; 490 unsigned int mask = 0; 491 492 if (!tun) 493 return POLLERR; 494 495 sk = tun->sk; 496 497 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name); 498 499 poll_wait(file, &tun->socket.wait, wait); 500 501 if (!skb_queue_empty(&tun->readq)) 502 mask |= POLLIN | POLLRDNORM; 503 504 if (sock_writeable(sk) || 505 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) && 506 sock_writeable(sk))) 507 mask |= POLLOUT | POLLWRNORM; 508 509 if (tun->dev->reg_state != NETREG_REGISTERED) 510 mask = POLLERR; 511 512 tun_put(tun); 513 return mask; 514 } 515 516 /* prepad is the amount to reserve at front. len is length after that. 517 * linear is a hint as to how much to copy (usually headers). */ 518 static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun, 519 size_t prepad, size_t len, 520 size_t linear, int noblock) 521 { 522 struct sock *sk = tun->sk; 523 struct sk_buff *skb; 524 int err; 525 526 /* Under a page? Don't bother with paged skb. */ 527 if (prepad + len < PAGE_SIZE || !linear) 528 linear = len; 529 530 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 531 &err); 532 if (!skb) 533 return ERR_PTR(err); 534 535 skb_reserve(skb, prepad); 536 skb_put(skb, linear); 537 skb->data_len = len - linear; 538 skb->len += len - linear; 539 540 return skb; 541 } 542 543 /* Get packet from user space buffer */ 544 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, 545 const struct iovec *iv, size_t count, 546 int noblock) 547 { 548 struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) }; 549 struct sk_buff *skb; 550 size_t len = count, align = 0; 551 struct virtio_net_hdr gso = { 0 }; 552 int offset = 0; 553 554 if (!(tun->flags & TUN_NO_PI)) { 555 if ((len -= sizeof(pi)) > count) 556 return -EINVAL; 557 558 if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi))) 559 return -EFAULT; 560 offset += sizeof(pi); 561 } 562 563 if (tun->flags & TUN_VNET_HDR) { 564 if ((len -= sizeof(gso)) > count) 565 return -EINVAL; 566 567 if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso))) 568 return -EFAULT; 569 570 if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 571 gso.csum_start + gso.csum_offset + 2 > gso.hdr_len) 572 gso.hdr_len = gso.csum_start + gso.csum_offset + 2; 573 574 if (gso.hdr_len > len) 575 return -EINVAL; 576 offset += sizeof(gso); 577 } 578 579 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { 580 align = NET_IP_ALIGN; 581 if (unlikely(len < ETH_HLEN || 582 (gso.hdr_len && gso.hdr_len < ETH_HLEN))) 583 return -EINVAL; 584 } 585 586 skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock); 587 if (IS_ERR(skb)) { 588 if (PTR_ERR(skb) != -EAGAIN) 589 tun->dev->stats.rx_dropped++; 590 return PTR_ERR(skb); 591 } 592 593 if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) { 594 tun->dev->stats.rx_dropped++; 595 kfree_skb(skb); 596 return -EFAULT; 597 } 598 599 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 600 if (!skb_partial_csum_set(skb, gso.csum_start, 601 gso.csum_offset)) { 602 tun->dev->stats.rx_frame_errors++; 603 kfree_skb(skb); 604 return -EINVAL; 605 } 606 } else if (tun->flags & TUN_NOCHECKSUM) 607 skb->ip_summed = CHECKSUM_UNNECESSARY; 608 609 switch (tun->flags & TUN_TYPE_MASK) { 610 case TUN_TUN_DEV: 611 if (tun->flags & TUN_NO_PI) { 612 switch (skb->data[0] & 0xf0) { 613 case 0x40: 614 pi.proto = htons(ETH_P_IP); 615 break; 616 case 0x60: 617 pi.proto = htons(ETH_P_IPV6); 618 break; 619 default: 620 tun->dev->stats.rx_dropped++; 621 kfree_skb(skb); 622 return -EINVAL; 623 } 624 } 625 626 skb_reset_mac_header(skb); 627 skb->protocol = pi.proto; 628 skb->dev = tun->dev; 629 break; 630 case TUN_TAP_DEV: 631 skb->protocol = eth_type_trans(skb, tun->dev); 632 break; 633 }; 634 635 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 636 pr_debug("GSO!\n"); 637 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 638 case VIRTIO_NET_HDR_GSO_TCPV4: 639 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; 640 break; 641 case VIRTIO_NET_HDR_GSO_TCPV6: 642 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; 643 break; 644 default: 645 tun->dev->stats.rx_frame_errors++; 646 kfree_skb(skb); 647 return -EINVAL; 648 } 649 650 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN) 651 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; 652 653 skb_shinfo(skb)->gso_size = gso.gso_size; 654 if (skb_shinfo(skb)->gso_size == 0) { 655 tun->dev->stats.rx_frame_errors++; 656 kfree_skb(skb); 657 return -EINVAL; 658 } 659 660 /* Header must be checked, and gso_segs computed. */ 661 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 662 skb_shinfo(skb)->gso_segs = 0; 663 } 664 665 netif_rx_ni(skb); 666 667 tun->dev->stats.rx_packets++; 668 tun->dev->stats.rx_bytes += len; 669 670 return count; 671 } 672 673 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, 674 unsigned long count, loff_t pos) 675 { 676 struct file *file = iocb->ki_filp; 677 struct tun_struct *tun = tun_get(file); 678 ssize_t result; 679 680 if (!tun) 681 return -EBADFD; 682 683 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count); 684 685 result = tun_get_user(tun, iv, iov_length(iv, count), 686 file->f_flags & O_NONBLOCK); 687 688 tun_put(tun); 689 return result; 690 } 691 692 /* Put packet to the user space buffer */ 693 static __inline__ ssize_t tun_put_user(struct tun_struct *tun, 694 struct sk_buff *skb, 695 const struct iovec *iv, int len) 696 { 697 struct tun_pi pi = { 0, skb->protocol }; 698 ssize_t total = 0; 699 700 if (!(tun->flags & TUN_NO_PI)) { 701 if ((len -= sizeof(pi)) < 0) 702 return -EINVAL; 703 704 if (len < skb->len) { 705 /* Packet will be striped */ 706 pi.flags |= TUN_PKT_STRIP; 707 } 708 709 if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi))) 710 return -EFAULT; 711 total += sizeof(pi); 712 } 713 714 if (tun->flags & TUN_VNET_HDR) { 715 struct virtio_net_hdr gso = { 0 }; /* no info leak */ 716 if ((len -= sizeof(gso)) < 0) 717 return -EINVAL; 718 719 if (skb_is_gso(skb)) { 720 struct skb_shared_info *sinfo = skb_shinfo(skb); 721 722 /* This is a hint as to how much should be linear. */ 723 gso.hdr_len = skb_headlen(skb); 724 gso.gso_size = sinfo->gso_size; 725 if (sinfo->gso_type & SKB_GSO_TCPV4) 726 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 727 else if (sinfo->gso_type & SKB_GSO_TCPV6) 728 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 729 else 730 BUG(); 731 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 732 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 733 } else 734 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE; 735 736 if (skb->ip_summed == CHECKSUM_PARTIAL) { 737 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 738 gso.csum_start = skb->csum_start - skb_headroom(skb); 739 gso.csum_offset = skb->csum_offset; 740 } /* else everything is zero */ 741 742 if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total, 743 sizeof(gso)))) 744 return -EFAULT; 745 total += sizeof(gso); 746 } 747 748 len = min_t(int, skb->len, len); 749 750 skb_copy_datagram_const_iovec(skb, 0, iv, total, len); 751 total += len; 752 753 tun->dev->stats.tx_packets++; 754 tun->dev->stats.tx_bytes += len; 755 756 return total; 757 } 758 759 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv, 760 unsigned long count, loff_t pos) 761 { 762 struct file *file = iocb->ki_filp; 763 struct tun_file *tfile = file->private_data; 764 struct tun_struct *tun = __tun_get(tfile); 765 DECLARE_WAITQUEUE(wait, current); 766 struct sk_buff *skb; 767 ssize_t len, ret = 0; 768 769 if (!tun) 770 return -EBADFD; 771 772 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name); 773 774 len = iov_length(iv, count); 775 if (len < 0) { 776 ret = -EINVAL; 777 goto out; 778 } 779 780 add_wait_queue(&tun->socket.wait, &wait); 781 while (len) { 782 current->state = TASK_INTERRUPTIBLE; 783 784 /* Read frames from the queue */ 785 if (!(skb=skb_dequeue(&tun->readq))) { 786 if (file->f_flags & O_NONBLOCK) { 787 ret = -EAGAIN; 788 break; 789 } 790 if (signal_pending(current)) { 791 ret = -ERESTARTSYS; 792 break; 793 } 794 if (tun->dev->reg_state != NETREG_REGISTERED) { 795 ret = -EIO; 796 break; 797 } 798 799 /* Nothing to read, let's sleep */ 800 schedule(); 801 continue; 802 } 803 netif_wake_queue(tun->dev); 804 805 ret = tun_put_user(tun, skb, iv, len); 806 kfree_skb(skb); 807 break; 808 } 809 810 current->state = TASK_RUNNING; 811 remove_wait_queue(&tun->socket.wait, &wait); 812 813 out: 814 tun_put(tun); 815 return ret; 816 } 817 818 static void tun_setup(struct net_device *dev) 819 { 820 struct tun_struct *tun = netdev_priv(dev); 821 822 skb_queue_head_init(&tun->readq); 823 824 tun->owner = -1; 825 tun->group = -1; 826 827 dev->ethtool_ops = &tun_ethtool_ops; 828 dev->destructor = tun_free_netdev; 829 } 830 831 /* Trivial set of netlink ops to allow deleting tun or tap 832 * device with netlink. 833 */ 834 static int tun_validate(struct nlattr *tb[], struct nlattr *data[]) 835 { 836 return -EINVAL; 837 } 838 839 static struct rtnl_link_ops tun_link_ops __read_mostly = { 840 .kind = DRV_NAME, 841 .priv_size = sizeof(struct tun_struct), 842 .setup = tun_setup, 843 .validate = tun_validate, 844 }; 845 846 static void tun_sock_write_space(struct sock *sk) 847 { 848 struct tun_struct *tun; 849 850 if (!sock_writeable(sk)) 851 return; 852 853 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags)) 854 return; 855 856 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) 857 wake_up_interruptible_sync(sk->sk_sleep); 858 859 tun = container_of(sk, struct tun_sock, sk)->tun; 860 kill_fasync(&tun->fasync, SIGIO, POLL_OUT); 861 } 862 863 static void tun_sock_destruct(struct sock *sk) 864 { 865 free_netdev(container_of(sk, struct tun_sock, sk)->tun->dev); 866 } 867 868 static struct proto tun_proto = { 869 .name = "tun", 870 .owner = THIS_MODULE, 871 .obj_size = sizeof(struct tun_sock), 872 }; 873 874 static int tun_flags(struct tun_struct *tun) 875 { 876 int flags = 0; 877 878 if (tun->flags & TUN_TUN_DEV) 879 flags |= IFF_TUN; 880 else 881 flags |= IFF_TAP; 882 883 if (tun->flags & TUN_NO_PI) 884 flags |= IFF_NO_PI; 885 886 if (tun->flags & TUN_ONE_QUEUE) 887 flags |= IFF_ONE_QUEUE; 888 889 if (tun->flags & TUN_VNET_HDR) 890 flags |= IFF_VNET_HDR; 891 892 return flags; 893 } 894 895 static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr, 896 char *buf) 897 { 898 struct tun_struct *tun = netdev_priv(to_net_dev(dev)); 899 return sprintf(buf, "0x%x\n", tun_flags(tun)); 900 } 901 902 static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr, 903 char *buf) 904 { 905 struct tun_struct *tun = netdev_priv(to_net_dev(dev)); 906 return sprintf(buf, "%d\n", tun->owner); 907 } 908 909 static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr, 910 char *buf) 911 { 912 struct tun_struct *tun = netdev_priv(to_net_dev(dev)); 913 return sprintf(buf, "%d\n", tun->group); 914 } 915 916 static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL); 917 static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL); 918 static DEVICE_ATTR(group, 0444, tun_show_group, NULL); 919 920 static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) 921 { 922 struct sock *sk; 923 struct tun_struct *tun; 924 struct net_device *dev; 925 int err; 926 927 dev = __dev_get_by_name(net, ifr->ifr_name); 928 if (dev) { 929 if (ifr->ifr_flags & IFF_TUN_EXCL) 930 return -EBUSY; 931 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops) 932 tun = netdev_priv(dev); 933 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops) 934 tun = netdev_priv(dev); 935 else 936 return -EINVAL; 937 938 err = tun_attach(tun, file); 939 if (err < 0) 940 return err; 941 } 942 else { 943 char *name; 944 unsigned long flags = 0; 945 946 err = -EINVAL; 947 948 if (!capable(CAP_NET_ADMIN)) 949 return -EPERM; 950 951 /* Set dev type */ 952 if (ifr->ifr_flags & IFF_TUN) { 953 /* TUN device */ 954 flags |= TUN_TUN_DEV; 955 name = "tun%d"; 956 } else if (ifr->ifr_flags & IFF_TAP) { 957 /* TAP device */ 958 flags |= TUN_TAP_DEV; 959 name = "tap%d"; 960 } else 961 goto failed; 962 963 if (*ifr->ifr_name) 964 name = ifr->ifr_name; 965 966 dev = alloc_netdev(sizeof(struct tun_struct), name, 967 tun_setup); 968 if (!dev) 969 return -ENOMEM; 970 971 dev_net_set(dev, net); 972 dev->rtnl_link_ops = &tun_link_ops; 973 974 tun = netdev_priv(dev); 975 tun->dev = dev; 976 tun->flags = flags; 977 tun->txflt.count = 0; 978 979 err = -ENOMEM; 980 sk = sk_alloc(net, AF_UNSPEC, GFP_KERNEL, &tun_proto); 981 if (!sk) 982 goto err_free_dev; 983 984 init_waitqueue_head(&tun->socket.wait); 985 sock_init_data(&tun->socket, sk); 986 sk->sk_write_space = tun_sock_write_space; 987 sk->sk_sndbuf = INT_MAX; 988 989 tun->sk = sk; 990 container_of(sk, struct tun_sock, sk)->tun = tun; 991 992 tun_net_init(dev); 993 994 if (strchr(dev->name, '%')) { 995 err = dev_alloc_name(dev, dev->name); 996 if (err < 0) 997 goto err_free_sk; 998 } 999 1000 err = -EINVAL; 1001 err = register_netdevice(tun->dev); 1002 if (err < 0) 1003 goto err_free_sk; 1004 1005 if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) || 1006 device_create_file(&tun->dev->dev, &dev_attr_owner) || 1007 device_create_file(&tun->dev->dev, &dev_attr_group)) 1008 printk(KERN_ERR "Failed to create tun sysfs files\n"); 1009 1010 sk->sk_destruct = tun_sock_destruct; 1011 1012 err = tun_attach(tun, file); 1013 if (err < 0) 1014 goto failed; 1015 } 1016 1017 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name); 1018 1019 if (ifr->ifr_flags & IFF_NO_PI) 1020 tun->flags |= TUN_NO_PI; 1021 else 1022 tun->flags &= ~TUN_NO_PI; 1023 1024 if (ifr->ifr_flags & IFF_ONE_QUEUE) 1025 tun->flags |= TUN_ONE_QUEUE; 1026 else 1027 tun->flags &= ~TUN_ONE_QUEUE; 1028 1029 if (ifr->ifr_flags & IFF_VNET_HDR) 1030 tun->flags |= TUN_VNET_HDR; 1031 else 1032 tun->flags &= ~TUN_VNET_HDR; 1033 1034 /* Make sure persistent devices do not get stuck in 1035 * xoff state. 1036 */ 1037 if (netif_running(tun->dev)) 1038 netif_wake_queue(tun->dev); 1039 1040 strcpy(ifr->ifr_name, tun->dev->name); 1041 return 0; 1042 1043 err_free_sk: 1044 sock_put(sk); 1045 err_free_dev: 1046 free_netdev(dev); 1047 failed: 1048 return err; 1049 } 1050 1051 static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr) 1052 { 1053 struct tun_struct *tun = tun_get(file); 1054 1055 if (!tun) 1056 return -EBADFD; 1057 1058 DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name); 1059 1060 strcpy(ifr->ifr_name, tun->dev->name); 1061 1062 ifr->ifr_flags = tun_flags(tun); 1063 1064 tun_put(tun); 1065 return 0; 1066 } 1067 1068 /* This is like a cut-down ethtool ops, except done via tun fd so no 1069 * privs required. */ 1070 static int set_offload(struct net_device *dev, unsigned long arg) 1071 { 1072 unsigned int old_features, features; 1073 1074 old_features = dev->features; 1075 /* Unset features, set them as we chew on the arg. */ 1076 features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST 1077 |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6)); 1078 1079 if (arg & TUN_F_CSUM) { 1080 features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; 1081 arg &= ~TUN_F_CSUM; 1082 1083 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) { 1084 if (arg & TUN_F_TSO_ECN) { 1085 features |= NETIF_F_TSO_ECN; 1086 arg &= ~TUN_F_TSO_ECN; 1087 } 1088 if (arg & TUN_F_TSO4) 1089 features |= NETIF_F_TSO; 1090 if (arg & TUN_F_TSO6) 1091 features |= NETIF_F_TSO6; 1092 arg &= ~(TUN_F_TSO4|TUN_F_TSO6); 1093 } 1094 } 1095 1096 /* This gives the user a way to test for new features in future by 1097 * trying to set them. */ 1098 if (arg) 1099 return -EINVAL; 1100 1101 dev->features = features; 1102 if (old_features != dev->features) 1103 netdev_features_change(dev); 1104 1105 return 0; 1106 } 1107 1108 static int tun_chr_ioctl(struct inode *inode, struct file *file, 1109 unsigned int cmd, unsigned long arg) 1110 { 1111 struct tun_file *tfile = file->private_data; 1112 struct tun_struct *tun; 1113 void __user* argp = (void __user*)arg; 1114 struct ifreq ifr; 1115 int sndbuf; 1116 int ret; 1117 1118 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89) 1119 if (copy_from_user(&ifr, argp, sizeof ifr)) 1120 return -EFAULT; 1121 1122 if (cmd == TUNGETFEATURES) { 1123 /* Currently this just means: "what IFF flags are valid?". 1124 * This is needed because we never checked for invalid flags on 1125 * TUNSETIFF. */ 1126 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE | 1127 IFF_VNET_HDR, 1128 (unsigned int __user*)argp); 1129 } 1130 1131 tun = __tun_get(tfile); 1132 if (cmd == TUNSETIFF && !tun) { 1133 int err; 1134 1135 ifr.ifr_name[IFNAMSIZ-1] = '\0'; 1136 1137 rtnl_lock(); 1138 err = tun_set_iff(tfile->net, file, &ifr); 1139 rtnl_unlock(); 1140 1141 if (err) 1142 return err; 1143 1144 if (copy_to_user(argp, &ifr, sizeof(ifr))) 1145 return -EFAULT; 1146 return 0; 1147 } 1148 1149 1150 if (!tun) 1151 return -EBADFD; 1152 1153 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd); 1154 1155 ret = 0; 1156 switch (cmd) { 1157 case TUNGETIFF: 1158 ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr); 1159 if (ret) 1160 break; 1161 1162 if (copy_to_user(argp, &ifr, sizeof(ifr))) 1163 ret = -EFAULT; 1164 break; 1165 1166 case TUNSETNOCSUM: 1167 /* Disable/Enable checksum */ 1168 if (arg) 1169 tun->flags |= TUN_NOCHECKSUM; 1170 else 1171 tun->flags &= ~TUN_NOCHECKSUM; 1172 1173 DBG(KERN_INFO "%s: checksum %s\n", 1174 tun->dev->name, arg ? "disabled" : "enabled"); 1175 break; 1176 1177 case TUNSETPERSIST: 1178 /* Disable/Enable persist mode */ 1179 if (arg) 1180 tun->flags |= TUN_PERSIST; 1181 else 1182 tun->flags &= ~TUN_PERSIST; 1183 1184 DBG(KERN_INFO "%s: persist %s\n", 1185 tun->dev->name, arg ? "enabled" : "disabled"); 1186 break; 1187 1188 case TUNSETOWNER: 1189 /* Set owner of the device */ 1190 tun->owner = (uid_t) arg; 1191 1192 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner); 1193 break; 1194 1195 case TUNSETGROUP: 1196 /* Set group of the device */ 1197 tun->group= (gid_t) arg; 1198 1199 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group); 1200 break; 1201 1202 case TUNSETLINK: 1203 /* Only allow setting the type when the interface is down */ 1204 rtnl_lock(); 1205 if (tun->dev->flags & IFF_UP) { 1206 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n", 1207 tun->dev->name); 1208 ret = -EBUSY; 1209 } else { 1210 tun->dev->type = (int) arg; 1211 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type); 1212 ret = 0; 1213 } 1214 rtnl_unlock(); 1215 break; 1216 1217 #ifdef TUN_DEBUG 1218 case TUNSETDEBUG: 1219 tun->debug = arg; 1220 break; 1221 #endif 1222 case TUNSETOFFLOAD: 1223 rtnl_lock(); 1224 ret = set_offload(tun->dev, arg); 1225 rtnl_unlock(); 1226 break; 1227 1228 case TUNSETTXFILTER: 1229 /* Can be set only for TAPs */ 1230 ret = -EINVAL; 1231 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) 1232 break; 1233 rtnl_lock(); 1234 ret = update_filter(&tun->txflt, (void __user *)arg); 1235 rtnl_unlock(); 1236 break; 1237 1238 case SIOCGIFHWADDR: 1239 /* Get hw addres */ 1240 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN); 1241 ifr.ifr_hwaddr.sa_family = tun->dev->type; 1242 if (copy_to_user(argp, &ifr, sizeof ifr)) 1243 ret = -EFAULT; 1244 break; 1245 1246 case SIOCSIFHWADDR: 1247 /* Set hw address */ 1248 DBG(KERN_DEBUG "%s: set hw address: %pM\n", 1249 tun->dev->name, ifr.ifr_hwaddr.sa_data); 1250 1251 rtnl_lock(); 1252 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr); 1253 rtnl_unlock(); 1254 break; 1255 1256 case TUNGETSNDBUF: 1257 sndbuf = tun->sk->sk_sndbuf; 1258 if (copy_to_user(argp, &sndbuf, sizeof(sndbuf))) 1259 ret = -EFAULT; 1260 break; 1261 1262 case TUNSETSNDBUF: 1263 if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) { 1264 ret = -EFAULT; 1265 break; 1266 } 1267 1268 tun->sk->sk_sndbuf = sndbuf; 1269 break; 1270 1271 default: 1272 ret = -EINVAL; 1273 break; 1274 }; 1275 1276 tun_put(tun); 1277 return ret; 1278 } 1279 1280 static int tun_chr_fasync(int fd, struct file *file, int on) 1281 { 1282 struct tun_struct *tun = tun_get(file); 1283 int ret; 1284 1285 if (!tun) 1286 return -EBADFD; 1287 1288 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on); 1289 1290 lock_kernel(); 1291 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0) 1292 goto out; 1293 1294 if (on) { 1295 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0); 1296 if (ret) 1297 goto out; 1298 tun->flags |= TUN_FASYNC; 1299 } else 1300 tun->flags &= ~TUN_FASYNC; 1301 ret = 0; 1302 out: 1303 unlock_kernel(); 1304 tun_put(tun); 1305 return ret; 1306 } 1307 1308 static int tun_chr_open(struct inode *inode, struct file * file) 1309 { 1310 struct tun_file *tfile; 1311 cycle_kernel_lock(); 1312 DBG1(KERN_INFO "tunX: tun_chr_open\n"); 1313 1314 tfile = kmalloc(sizeof(*tfile), GFP_KERNEL); 1315 if (!tfile) 1316 return -ENOMEM; 1317 atomic_set(&tfile->count, 0); 1318 tfile->tun = NULL; 1319 tfile->net = get_net(current->nsproxy->net_ns); 1320 file->private_data = tfile; 1321 return 0; 1322 } 1323 1324 static int tun_chr_close(struct inode *inode, struct file *file) 1325 { 1326 struct tun_file *tfile = file->private_data; 1327 struct tun_struct *tun; 1328 1329 tun = __tun_get(tfile); 1330 if (tun) { 1331 struct net_device *dev = tun->dev; 1332 1333 DBG(KERN_INFO "%s: tun_chr_close\n", dev->name); 1334 1335 __tun_detach(tun); 1336 1337 /* If desireable, unregister the netdevice. */ 1338 if (!(tun->flags & TUN_PERSIST)) { 1339 rtnl_lock(); 1340 if (dev->reg_state == NETREG_REGISTERED) 1341 unregister_netdevice(dev); 1342 rtnl_unlock(); 1343 } 1344 } 1345 1346 tun = tfile->tun; 1347 if (tun) 1348 sock_put(tun->sk); 1349 1350 put_net(tfile->net); 1351 kfree(tfile); 1352 1353 return 0; 1354 } 1355 1356 static const struct file_operations tun_fops = { 1357 .owner = THIS_MODULE, 1358 .llseek = no_llseek, 1359 .read = do_sync_read, 1360 .aio_read = tun_chr_aio_read, 1361 .write = do_sync_write, 1362 .aio_write = tun_chr_aio_write, 1363 .poll = tun_chr_poll, 1364 .ioctl = tun_chr_ioctl, 1365 .open = tun_chr_open, 1366 .release = tun_chr_close, 1367 .fasync = tun_chr_fasync 1368 }; 1369 1370 static struct miscdevice tun_miscdev = { 1371 .minor = TUN_MINOR, 1372 .name = "tun", 1373 .devnode = "net/tun", 1374 .fops = &tun_fops, 1375 }; 1376 1377 /* ethtool interface */ 1378 1379 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) 1380 { 1381 cmd->supported = 0; 1382 cmd->advertising = 0; 1383 cmd->speed = SPEED_10; 1384 cmd->duplex = DUPLEX_FULL; 1385 cmd->port = PORT_TP; 1386 cmd->phy_address = 0; 1387 cmd->transceiver = XCVR_INTERNAL; 1388 cmd->autoneg = AUTONEG_DISABLE; 1389 cmd->maxtxpkt = 0; 1390 cmd->maxrxpkt = 0; 1391 return 0; 1392 } 1393 1394 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) 1395 { 1396 struct tun_struct *tun = netdev_priv(dev); 1397 1398 strcpy(info->driver, DRV_NAME); 1399 strcpy(info->version, DRV_VERSION); 1400 strcpy(info->fw_version, "N/A"); 1401 1402 switch (tun->flags & TUN_TYPE_MASK) { 1403 case TUN_TUN_DEV: 1404 strcpy(info->bus_info, "tun"); 1405 break; 1406 case TUN_TAP_DEV: 1407 strcpy(info->bus_info, "tap"); 1408 break; 1409 } 1410 } 1411 1412 static u32 tun_get_msglevel(struct net_device *dev) 1413 { 1414 #ifdef TUN_DEBUG 1415 struct tun_struct *tun = netdev_priv(dev); 1416 return tun->debug; 1417 #else 1418 return -EOPNOTSUPP; 1419 #endif 1420 } 1421 1422 static void tun_set_msglevel(struct net_device *dev, u32 value) 1423 { 1424 #ifdef TUN_DEBUG 1425 struct tun_struct *tun = netdev_priv(dev); 1426 tun->debug = value; 1427 #endif 1428 } 1429 1430 static u32 tun_get_link(struct net_device *dev) 1431 { 1432 struct tun_struct *tun = netdev_priv(dev); 1433 return !!tun->tfile; 1434 } 1435 1436 static u32 tun_get_rx_csum(struct net_device *dev) 1437 { 1438 struct tun_struct *tun = netdev_priv(dev); 1439 return (tun->flags & TUN_NOCHECKSUM) == 0; 1440 } 1441 1442 static int tun_set_rx_csum(struct net_device *dev, u32 data) 1443 { 1444 struct tun_struct *tun = netdev_priv(dev); 1445 if (data) 1446 tun->flags &= ~TUN_NOCHECKSUM; 1447 else 1448 tun->flags |= TUN_NOCHECKSUM; 1449 return 0; 1450 } 1451 1452 static const struct ethtool_ops tun_ethtool_ops = { 1453 .get_settings = tun_get_settings, 1454 .get_drvinfo = tun_get_drvinfo, 1455 .get_msglevel = tun_get_msglevel, 1456 .set_msglevel = tun_set_msglevel, 1457 .get_link = tun_get_link, 1458 .get_rx_csum = tun_get_rx_csum, 1459 .set_rx_csum = tun_set_rx_csum 1460 }; 1461 1462 1463 static int __init tun_init(void) 1464 { 1465 int ret = 0; 1466 1467 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION); 1468 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT); 1469 1470 ret = rtnl_link_register(&tun_link_ops); 1471 if (ret) { 1472 printk(KERN_ERR "tun: Can't register link_ops\n"); 1473 goto err_linkops; 1474 } 1475 1476 ret = misc_register(&tun_miscdev); 1477 if (ret) { 1478 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR); 1479 goto err_misc; 1480 } 1481 return 0; 1482 err_misc: 1483 rtnl_link_unregister(&tun_link_ops); 1484 err_linkops: 1485 return ret; 1486 } 1487 1488 static void tun_cleanup(void) 1489 { 1490 misc_deregister(&tun_miscdev); 1491 rtnl_link_unregister(&tun_link_ops); 1492 } 1493 1494 module_init(tun_init); 1495 module_exit(tun_cleanup); 1496 MODULE_DESCRIPTION(DRV_DESCRIPTION); 1497 MODULE_AUTHOR(DRV_COPYRIGHT); 1498 MODULE_LICENSE("GPL"); 1499 MODULE_ALIAS_MISCDEV(TUN_MINOR); 1500