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 net_device *dev; 107 struct fasync_struct *fasync; 108 109 struct tap_filter txflt; 110 struct socket socket; 111 112 #ifdef TUN_DEBUG 113 int debug; 114 #endif 115 }; 116 117 struct tun_sock { 118 struct sock sk; 119 struct tun_struct *tun; 120 }; 121 122 static inline struct tun_sock *tun_sk(struct sock *sk) 123 { 124 return container_of(sk, struct tun_sock, sk); 125 } 126 127 static int tun_attach(struct tun_struct *tun, struct file *file) 128 { 129 struct tun_file *tfile = file->private_data; 130 int err; 131 132 ASSERT_RTNL(); 133 134 netif_tx_lock_bh(tun->dev); 135 136 err = -EINVAL; 137 if (tfile->tun) 138 goto out; 139 140 err = -EBUSY; 141 if (tun->tfile) 142 goto out; 143 144 err = 0; 145 tfile->tun = tun; 146 tun->tfile = tfile; 147 dev_hold(tun->dev); 148 sock_hold(tun->socket.sk); 149 atomic_inc(&tfile->count); 150 151 out: 152 netif_tx_unlock_bh(tun->dev); 153 return err; 154 } 155 156 static void __tun_detach(struct tun_struct *tun) 157 { 158 /* Detach from net device */ 159 netif_tx_lock_bh(tun->dev); 160 tun->tfile = NULL; 161 netif_tx_unlock_bh(tun->dev); 162 163 /* Drop read queue */ 164 skb_queue_purge(&tun->socket.sk->sk_receive_queue); 165 166 /* Drop the extra count on the net device */ 167 dev_put(tun->dev); 168 } 169 170 static void tun_detach(struct tun_struct *tun) 171 { 172 rtnl_lock(); 173 __tun_detach(tun); 174 rtnl_unlock(); 175 } 176 177 static struct tun_struct *__tun_get(struct tun_file *tfile) 178 { 179 struct tun_struct *tun = NULL; 180 181 if (atomic_inc_not_zero(&tfile->count)) 182 tun = tfile->tun; 183 184 return tun; 185 } 186 187 static struct tun_struct *tun_get(struct file *file) 188 { 189 return __tun_get(file->private_data); 190 } 191 192 static void tun_put(struct tun_struct *tun) 193 { 194 struct tun_file *tfile = tun->tfile; 195 196 if (atomic_dec_and_test(&tfile->count)) 197 tun_detach(tfile->tun); 198 } 199 200 /* TAP filterting */ 201 static void addr_hash_set(u32 *mask, const u8 *addr) 202 { 203 int n = ether_crc(ETH_ALEN, addr) >> 26; 204 mask[n >> 5] |= (1 << (n & 31)); 205 } 206 207 static unsigned int addr_hash_test(const u32 *mask, const u8 *addr) 208 { 209 int n = ether_crc(ETH_ALEN, addr) >> 26; 210 return mask[n >> 5] & (1 << (n & 31)); 211 } 212 213 static int update_filter(struct tap_filter *filter, void __user *arg) 214 { 215 struct { u8 u[ETH_ALEN]; } *addr; 216 struct tun_filter uf; 217 int err, alen, n, nexact; 218 219 if (copy_from_user(&uf, arg, sizeof(uf))) 220 return -EFAULT; 221 222 if (!uf.count) { 223 /* Disabled */ 224 filter->count = 0; 225 return 0; 226 } 227 228 alen = ETH_ALEN * uf.count; 229 addr = kmalloc(alen, GFP_KERNEL); 230 if (!addr) 231 return -ENOMEM; 232 233 if (copy_from_user(addr, arg + sizeof(uf), alen)) { 234 err = -EFAULT; 235 goto done; 236 } 237 238 /* The filter is updated without holding any locks. Which is 239 * perfectly safe. We disable it first and in the worst 240 * case we'll accept a few undesired packets. */ 241 filter->count = 0; 242 wmb(); 243 244 /* Use first set of addresses as an exact filter */ 245 for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++) 246 memcpy(filter->addr[n], addr[n].u, ETH_ALEN); 247 248 nexact = n; 249 250 /* Remaining multicast addresses are hashed, 251 * unicast will leave the filter disabled. */ 252 memset(filter->mask, 0, sizeof(filter->mask)); 253 for (; n < uf.count; n++) { 254 if (!is_multicast_ether_addr(addr[n].u)) { 255 err = 0; /* no filter */ 256 goto done; 257 } 258 addr_hash_set(filter->mask, addr[n].u); 259 } 260 261 /* For ALLMULTI just set the mask to all ones. 262 * This overrides the mask populated above. */ 263 if ((uf.flags & TUN_FLT_ALLMULTI)) 264 memset(filter->mask, ~0, sizeof(filter->mask)); 265 266 /* Now enable the filter */ 267 wmb(); 268 filter->count = nexact; 269 270 /* Return the number of exact filters */ 271 err = nexact; 272 273 done: 274 kfree(addr); 275 return err; 276 } 277 278 /* Returns: 0 - drop, !=0 - accept */ 279 static int run_filter(struct tap_filter *filter, const struct sk_buff *skb) 280 { 281 /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect 282 * at this point. */ 283 struct ethhdr *eh = (struct ethhdr *) skb->data; 284 int i; 285 286 /* Exact match */ 287 for (i = 0; i < filter->count; i++) 288 if (!compare_ether_addr(eh->h_dest, filter->addr[i])) 289 return 1; 290 291 /* Inexact match (multicast only) */ 292 if (is_multicast_ether_addr(eh->h_dest)) 293 return addr_hash_test(filter->mask, eh->h_dest); 294 295 return 0; 296 } 297 298 /* 299 * Checks whether the packet is accepted or not. 300 * Returns: 0 - drop, !=0 - accept 301 */ 302 static int check_filter(struct tap_filter *filter, const struct sk_buff *skb) 303 { 304 if (!filter->count) 305 return 1; 306 307 return run_filter(filter, skb); 308 } 309 310 /* Network device part of the driver */ 311 312 static const struct ethtool_ops tun_ethtool_ops; 313 314 /* Net device detach from fd. */ 315 static void tun_net_uninit(struct net_device *dev) 316 { 317 struct tun_struct *tun = netdev_priv(dev); 318 struct tun_file *tfile = tun->tfile; 319 320 /* Inform the methods they need to stop using the dev. 321 */ 322 if (tfile) { 323 wake_up_all(&tun->socket.wait); 324 if (atomic_dec_and_test(&tfile->count)) 325 __tun_detach(tun); 326 } 327 } 328 329 static void tun_free_netdev(struct net_device *dev) 330 { 331 struct tun_struct *tun = netdev_priv(dev); 332 333 sock_put(tun->socket.sk); 334 } 335 336 /* Net device open. */ 337 static int tun_net_open(struct net_device *dev) 338 { 339 netif_start_queue(dev); 340 return 0; 341 } 342 343 /* Net device close. */ 344 static int tun_net_close(struct net_device *dev) 345 { 346 netif_stop_queue(dev); 347 return 0; 348 } 349 350 /* Net device start xmit */ 351 static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) 352 { 353 struct tun_struct *tun = netdev_priv(dev); 354 355 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len); 356 357 /* Drop packet if interface is not attached */ 358 if (!tun->tfile) 359 goto drop; 360 361 /* Drop if the filter does not like it. 362 * This is a noop if the filter is disabled. 363 * Filter can be enabled only for the TAP devices. */ 364 if (!check_filter(&tun->txflt, skb)) 365 goto drop; 366 367 if (skb_queue_len(&tun->socket.sk->sk_receive_queue) >= dev->tx_queue_len) { 368 if (!(tun->flags & TUN_ONE_QUEUE)) { 369 /* Normal queueing mode. */ 370 /* Packet scheduler handles dropping of further packets. */ 371 netif_stop_queue(dev); 372 373 /* We won't see all dropped packets individually, so overrun 374 * error is more appropriate. */ 375 dev->stats.tx_fifo_errors++; 376 } else { 377 /* Single queue mode. 378 * Driver handles dropping of all packets itself. */ 379 goto drop; 380 } 381 } 382 383 /* Enqueue packet */ 384 skb_queue_tail(&tun->socket.sk->sk_receive_queue, skb); 385 dev->trans_start = jiffies; 386 387 /* Notify and wake up reader process */ 388 if (tun->flags & TUN_FASYNC) 389 kill_fasync(&tun->fasync, SIGIO, POLL_IN); 390 wake_up_interruptible(&tun->socket.wait); 391 return NETDEV_TX_OK; 392 393 drop: 394 dev->stats.tx_dropped++; 395 kfree_skb(skb); 396 return NETDEV_TX_OK; 397 } 398 399 static void tun_net_mclist(struct net_device *dev) 400 { 401 /* 402 * This callback is supposed to deal with mc filter in 403 * _rx_ path and has nothing to do with the _tx_ path. 404 * In rx path we always accept everything userspace gives us. 405 */ 406 return; 407 } 408 409 #define MIN_MTU 68 410 #define MAX_MTU 65535 411 412 static int 413 tun_net_change_mtu(struct net_device *dev, int new_mtu) 414 { 415 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU) 416 return -EINVAL; 417 dev->mtu = new_mtu; 418 return 0; 419 } 420 421 static const struct net_device_ops tun_netdev_ops = { 422 .ndo_uninit = tun_net_uninit, 423 .ndo_open = tun_net_open, 424 .ndo_stop = tun_net_close, 425 .ndo_start_xmit = tun_net_xmit, 426 .ndo_change_mtu = tun_net_change_mtu, 427 }; 428 429 static const struct net_device_ops tap_netdev_ops = { 430 .ndo_uninit = tun_net_uninit, 431 .ndo_open = tun_net_open, 432 .ndo_stop = tun_net_close, 433 .ndo_start_xmit = tun_net_xmit, 434 .ndo_change_mtu = tun_net_change_mtu, 435 .ndo_set_multicast_list = tun_net_mclist, 436 .ndo_set_mac_address = eth_mac_addr, 437 .ndo_validate_addr = eth_validate_addr, 438 }; 439 440 /* Initialize net device. */ 441 static void tun_net_init(struct net_device *dev) 442 { 443 struct tun_struct *tun = netdev_priv(dev); 444 445 switch (tun->flags & TUN_TYPE_MASK) { 446 case TUN_TUN_DEV: 447 dev->netdev_ops = &tun_netdev_ops; 448 449 /* Point-to-Point TUN Device */ 450 dev->hard_header_len = 0; 451 dev->addr_len = 0; 452 dev->mtu = 1500; 453 454 /* Zero header length */ 455 dev->type = ARPHRD_NONE; 456 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; 457 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 458 break; 459 460 case TUN_TAP_DEV: 461 dev->netdev_ops = &tap_netdev_ops; 462 /* Ethernet TAP Device */ 463 ether_setup(dev); 464 465 random_ether_addr(dev->dev_addr); 466 467 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 468 break; 469 } 470 } 471 472 /* Character device part */ 473 474 /* Poll */ 475 static unsigned int tun_chr_poll(struct file *file, poll_table * wait) 476 { 477 struct tun_file *tfile = file->private_data; 478 struct tun_struct *tun = __tun_get(tfile); 479 struct sock *sk; 480 unsigned int mask = 0; 481 482 if (!tun) 483 return POLLERR; 484 485 sk = tun->socket.sk; 486 487 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name); 488 489 poll_wait(file, &tun->socket.wait, wait); 490 491 if (!skb_queue_empty(&sk->sk_receive_queue)) 492 mask |= POLLIN | POLLRDNORM; 493 494 if (sock_writeable(sk) || 495 (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) && 496 sock_writeable(sk))) 497 mask |= POLLOUT | POLLWRNORM; 498 499 if (tun->dev->reg_state != NETREG_REGISTERED) 500 mask = POLLERR; 501 502 tun_put(tun); 503 return mask; 504 } 505 506 /* prepad is the amount to reserve at front. len is length after that. 507 * linear is a hint as to how much to copy (usually headers). */ 508 static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun, 509 size_t prepad, size_t len, 510 size_t linear, int noblock) 511 { 512 struct sock *sk = tun->socket.sk; 513 struct sk_buff *skb; 514 int err; 515 516 /* Under a page? Don't bother with paged skb. */ 517 if (prepad + len < PAGE_SIZE || !linear) 518 linear = len; 519 520 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 521 &err); 522 if (!skb) 523 return ERR_PTR(err); 524 525 skb_reserve(skb, prepad); 526 skb_put(skb, linear); 527 skb->data_len = len - linear; 528 skb->len += len - linear; 529 530 return skb; 531 } 532 533 /* Get packet from user space buffer */ 534 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, 535 const struct iovec *iv, size_t count, 536 int noblock) 537 { 538 struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) }; 539 struct sk_buff *skb; 540 size_t len = count, align = 0; 541 struct virtio_net_hdr gso = { 0 }; 542 int offset = 0; 543 544 if (!(tun->flags & TUN_NO_PI)) { 545 if ((len -= sizeof(pi)) > count) 546 return -EINVAL; 547 548 if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi))) 549 return -EFAULT; 550 offset += sizeof(pi); 551 } 552 553 if (tun->flags & TUN_VNET_HDR) { 554 if ((len -= sizeof(gso)) > count) 555 return -EINVAL; 556 557 if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso))) 558 return -EFAULT; 559 560 if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 561 gso.csum_start + gso.csum_offset + 2 > gso.hdr_len) 562 gso.hdr_len = gso.csum_start + gso.csum_offset + 2; 563 564 if (gso.hdr_len > len) 565 return -EINVAL; 566 offset += sizeof(gso); 567 } 568 569 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { 570 align = NET_IP_ALIGN; 571 if (unlikely(len < ETH_HLEN || 572 (gso.hdr_len && gso.hdr_len < ETH_HLEN))) 573 return -EINVAL; 574 } 575 576 skb = tun_alloc_skb(tun, align, len, gso.hdr_len, noblock); 577 if (IS_ERR(skb)) { 578 if (PTR_ERR(skb) != -EAGAIN) 579 tun->dev->stats.rx_dropped++; 580 return PTR_ERR(skb); 581 } 582 583 if (skb_copy_datagram_from_iovec(skb, 0, iv, offset, len)) { 584 tun->dev->stats.rx_dropped++; 585 kfree_skb(skb); 586 return -EFAULT; 587 } 588 589 if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 590 if (!skb_partial_csum_set(skb, gso.csum_start, 591 gso.csum_offset)) { 592 tun->dev->stats.rx_frame_errors++; 593 kfree_skb(skb); 594 return -EINVAL; 595 } 596 } else if (tun->flags & TUN_NOCHECKSUM) 597 skb->ip_summed = CHECKSUM_UNNECESSARY; 598 599 switch (tun->flags & TUN_TYPE_MASK) { 600 case TUN_TUN_DEV: 601 if (tun->flags & TUN_NO_PI) { 602 switch (skb->data[0] & 0xf0) { 603 case 0x40: 604 pi.proto = htons(ETH_P_IP); 605 break; 606 case 0x60: 607 pi.proto = htons(ETH_P_IPV6); 608 break; 609 default: 610 tun->dev->stats.rx_dropped++; 611 kfree_skb(skb); 612 return -EINVAL; 613 } 614 } 615 616 skb_reset_mac_header(skb); 617 skb->protocol = pi.proto; 618 skb->dev = tun->dev; 619 break; 620 case TUN_TAP_DEV: 621 skb->protocol = eth_type_trans(skb, tun->dev); 622 break; 623 }; 624 625 if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 626 pr_debug("GSO!\n"); 627 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 628 case VIRTIO_NET_HDR_GSO_TCPV4: 629 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; 630 break; 631 case VIRTIO_NET_HDR_GSO_TCPV6: 632 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; 633 break; 634 case VIRTIO_NET_HDR_GSO_UDP: 635 skb_shinfo(skb)->gso_type = SKB_GSO_UDP; 636 break; 637 default: 638 tun->dev->stats.rx_frame_errors++; 639 kfree_skb(skb); 640 return -EINVAL; 641 } 642 643 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN) 644 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; 645 646 skb_shinfo(skb)->gso_size = gso.gso_size; 647 if (skb_shinfo(skb)->gso_size == 0) { 648 tun->dev->stats.rx_frame_errors++; 649 kfree_skb(skb); 650 return -EINVAL; 651 } 652 653 /* Header must be checked, and gso_segs computed. */ 654 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 655 skb_shinfo(skb)->gso_segs = 0; 656 } 657 658 netif_rx_ni(skb); 659 660 tun->dev->stats.rx_packets++; 661 tun->dev->stats.rx_bytes += len; 662 663 return count; 664 } 665 666 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, 667 unsigned long count, loff_t pos) 668 { 669 struct file *file = iocb->ki_filp; 670 struct tun_struct *tun = tun_get(file); 671 ssize_t result; 672 673 if (!tun) 674 return -EBADFD; 675 676 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count); 677 678 result = tun_get_user(tun, iv, iov_length(iv, count), 679 file->f_flags & O_NONBLOCK); 680 681 tun_put(tun); 682 return result; 683 } 684 685 /* Put packet to the user space buffer */ 686 static __inline__ ssize_t tun_put_user(struct tun_struct *tun, 687 struct sk_buff *skb, 688 const struct iovec *iv, int len) 689 { 690 struct tun_pi pi = { 0, skb->protocol }; 691 ssize_t total = 0; 692 693 if (!(tun->flags & TUN_NO_PI)) { 694 if ((len -= sizeof(pi)) < 0) 695 return -EINVAL; 696 697 if (len < skb->len) { 698 /* Packet will be striped */ 699 pi.flags |= TUN_PKT_STRIP; 700 } 701 702 if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi))) 703 return -EFAULT; 704 total += sizeof(pi); 705 } 706 707 if (tun->flags & TUN_VNET_HDR) { 708 struct virtio_net_hdr gso = { 0 }; /* no info leak */ 709 if ((len -= sizeof(gso)) < 0) 710 return -EINVAL; 711 712 if (skb_is_gso(skb)) { 713 struct skb_shared_info *sinfo = skb_shinfo(skb); 714 715 /* This is a hint as to how much should be linear. */ 716 gso.hdr_len = skb_headlen(skb); 717 gso.gso_size = sinfo->gso_size; 718 if (sinfo->gso_type & SKB_GSO_TCPV4) 719 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 720 else if (sinfo->gso_type & SKB_GSO_TCPV6) 721 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 722 else if (sinfo->gso_type & SKB_GSO_UDP) 723 gso.gso_type = VIRTIO_NET_HDR_GSO_UDP; 724 else 725 BUG(); 726 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 727 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 728 } else 729 gso.gso_type = VIRTIO_NET_HDR_GSO_NONE; 730 731 if (skb->ip_summed == CHECKSUM_PARTIAL) { 732 gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 733 gso.csum_start = skb->csum_start - skb_headroom(skb); 734 gso.csum_offset = skb->csum_offset; 735 } /* else everything is zero */ 736 737 if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total, 738 sizeof(gso)))) 739 return -EFAULT; 740 total += sizeof(gso); 741 } 742 743 len = min_t(int, skb->len, len); 744 745 skb_copy_datagram_const_iovec(skb, 0, iv, total, len); 746 total += len; 747 748 tun->dev->stats.tx_packets++; 749 tun->dev->stats.tx_bytes += len; 750 751 return total; 752 } 753 754 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv, 755 unsigned long count, loff_t pos) 756 { 757 struct file *file = iocb->ki_filp; 758 struct tun_file *tfile = file->private_data; 759 struct tun_struct *tun = __tun_get(tfile); 760 DECLARE_WAITQUEUE(wait, current); 761 struct sk_buff *skb; 762 ssize_t len, ret = 0; 763 764 if (!tun) 765 return -EBADFD; 766 767 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name); 768 769 len = iov_length(iv, count); 770 if (len < 0) { 771 ret = -EINVAL; 772 goto out; 773 } 774 775 add_wait_queue(&tun->socket.wait, &wait); 776 while (len) { 777 current->state = TASK_INTERRUPTIBLE; 778 779 /* Read frames from the queue */ 780 if (!(skb=skb_dequeue(&tun->socket.sk->sk_receive_queue))) { 781 if (file->f_flags & O_NONBLOCK) { 782 ret = -EAGAIN; 783 break; 784 } 785 if (signal_pending(current)) { 786 ret = -ERESTARTSYS; 787 break; 788 } 789 if (tun->dev->reg_state != NETREG_REGISTERED) { 790 ret = -EIO; 791 break; 792 } 793 794 /* Nothing to read, let's sleep */ 795 schedule(); 796 continue; 797 } 798 netif_wake_queue(tun->dev); 799 800 ret = tun_put_user(tun, skb, iv, len); 801 kfree_skb(skb); 802 break; 803 } 804 805 current->state = TASK_RUNNING; 806 remove_wait_queue(&tun->socket.wait, &wait); 807 808 out: 809 tun_put(tun); 810 return ret; 811 } 812 813 static void tun_setup(struct net_device *dev) 814 { 815 struct tun_struct *tun = netdev_priv(dev); 816 817 tun->owner = -1; 818 tun->group = -1; 819 820 dev->ethtool_ops = &tun_ethtool_ops; 821 dev->destructor = tun_free_netdev; 822 } 823 824 /* Trivial set of netlink ops to allow deleting tun or tap 825 * device with netlink. 826 */ 827 static int tun_validate(struct nlattr *tb[], struct nlattr *data[]) 828 { 829 return -EINVAL; 830 } 831 832 static struct rtnl_link_ops tun_link_ops __read_mostly = { 833 .kind = DRV_NAME, 834 .priv_size = sizeof(struct tun_struct), 835 .setup = tun_setup, 836 .validate = tun_validate, 837 }; 838 839 static void tun_sock_write_space(struct sock *sk) 840 { 841 struct tun_struct *tun; 842 843 if (!sock_writeable(sk)) 844 return; 845 846 if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags)) 847 return; 848 849 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) 850 wake_up_interruptible_sync(sk->sk_sleep); 851 852 tun = container_of(sk, struct tun_sock, sk)->tun; 853 kill_fasync(&tun->fasync, SIGIO, POLL_OUT); 854 } 855 856 static void tun_sock_destruct(struct sock *sk) 857 { 858 free_netdev(container_of(sk, struct tun_sock, sk)->tun->dev); 859 } 860 861 static struct proto tun_proto = { 862 .name = "tun", 863 .owner = THIS_MODULE, 864 .obj_size = sizeof(struct tun_sock), 865 }; 866 867 static int tun_flags(struct tun_struct *tun) 868 { 869 int flags = 0; 870 871 if (tun->flags & TUN_TUN_DEV) 872 flags |= IFF_TUN; 873 else 874 flags |= IFF_TAP; 875 876 if (tun->flags & TUN_NO_PI) 877 flags |= IFF_NO_PI; 878 879 if (tun->flags & TUN_ONE_QUEUE) 880 flags |= IFF_ONE_QUEUE; 881 882 if (tun->flags & TUN_VNET_HDR) 883 flags |= IFF_VNET_HDR; 884 885 return flags; 886 } 887 888 static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr, 889 char *buf) 890 { 891 struct tun_struct *tun = netdev_priv(to_net_dev(dev)); 892 return sprintf(buf, "0x%x\n", tun_flags(tun)); 893 } 894 895 static ssize_t tun_show_owner(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, "%d\n", tun->owner); 900 } 901 902 static ssize_t tun_show_group(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->group); 907 } 908 909 static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL); 910 static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL); 911 static DEVICE_ATTR(group, 0444, tun_show_group, NULL); 912 913 static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) 914 { 915 struct sock *sk; 916 struct tun_struct *tun; 917 struct net_device *dev; 918 int err; 919 920 dev = __dev_get_by_name(net, ifr->ifr_name); 921 if (dev) { 922 const struct cred *cred = current_cred(); 923 924 if (ifr->ifr_flags & IFF_TUN_EXCL) 925 return -EBUSY; 926 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops) 927 tun = netdev_priv(dev); 928 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops) 929 tun = netdev_priv(dev); 930 else 931 return -EINVAL; 932 933 if (((tun->owner != -1 && cred->euid != tun->owner) || 934 (tun->group != -1 && !in_egroup_p(tun->group))) && 935 !capable(CAP_NET_ADMIN)) 936 return -EPERM; 937 err = security_tun_dev_attach(tun->socket.sk); 938 if (err < 0) 939 return err; 940 941 err = tun_attach(tun, file); 942 if (err < 0) 943 return err; 944 } 945 else { 946 char *name; 947 unsigned long flags = 0; 948 949 err = -EINVAL; 950 951 if (!capable(CAP_NET_ADMIN)) 952 return -EPERM; 953 err = security_tun_dev_create(); 954 if (err < 0) 955 return err; 956 957 /* Set dev type */ 958 if (ifr->ifr_flags & IFF_TUN) { 959 /* TUN device */ 960 flags |= TUN_TUN_DEV; 961 name = "tun%d"; 962 } else if (ifr->ifr_flags & IFF_TAP) { 963 /* TAP device */ 964 flags |= TUN_TAP_DEV; 965 name = "tap%d"; 966 } else 967 goto failed; 968 969 if (*ifr->ifr_name) 970 name = ifr->ifr_name; 971 972 dev = alloc_netdev(sizeof(struct tun_struct), name, 973 tun_setup); 974 if (!dev) 975 return -ENOMEM; 976 977 dev_net_set(dev, net); 978 dev->rtnl_link_ops = &tun_link_ops; 979 980 tun = netdev_priv(dev); 981 tun->dev = dev; 982 tun->flags = flags; 983 tun->txflt.count = 0; 984 985 err = -ENOMEM; 986 sk = sk_alloc(net, AF_UNSPEC, GFP_KERNEL, &tun_proto); 987 if (!sk) 988 goto err_free_dev; 989 990 init_waitqueue_head(&tun->socket.wait); 991 sock_init_data(&tun->socket, sk); 992 sk->sk_write_space = tun_sock_write_space; 993 sk->sk_sndbuf = INT_MAX; 994 995 container_of(sk, struct tun_sock, sk)->tun = tun; 996 997 security_tun_dev_post_create(sk); 998 999 tun_net_init(dev); 1000 1001 if (strchr(dev->name, '%')) { 1002 err = dev_alloc_name(dev, dev->name); 1003 if (err < 0) 1004 goto err_free_sk; 1005 } 1006 1007 err = register_netdevice(tun->dev); 1008 if (err < 0) 1009 goto err_free_sk; 1010 1011 if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) || 1012 device_create_file(&tun->dev->dev, &dev_attr_owner) || 1013 device_create_file(&tun->dev->dev, &dev_attr_group)) 1014 printk(KERN_ERR "Failed to create tun sysfs files\n"); 1015 1016 sk->sk_destruct = tun_sock_destruct; 1017 1018 err = tun_attach(tun, file); 1019 if (err < 0) 1020 goto failed; 1021 } 1022 1023 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name); 1024 1025 if (ifr->ifr_flags & IFF_NO_PI) 1026 tun->flags |= TUN_NO_PI; 1027 else 1028 tun->flags &= ~TUN_NO_PI; 1029 1030 if (ifr->ifr_flags & IFF_ONE_QUEUE) 1031 tun->flags |= TUN_ONE_QUEUE; 1032 else 1033 tun->flags &= ~TUN_ONE_QUEUE; 1034 1035 if (ifr->ifr_flags & IFF_VNET_HDR) 1036 tun->flags |= TUN_VNET_HDR; 1037 else 1038 tun->flags &= ~TUN_VNET_HDR; 1039 1040 /* Make sure persistent devices do not get stuck in 1041 * xoff state. 1042 */ 1043 if (netif_running(tun->dev)) 1044 netif_wake_queue(tun->dev); 1045 1046 strcpy(ifr->ifr_name, tun->dev->name); 1047 return 0; 1048 1049 err_free_sk: 1050 sock_put(sk); 1051 err_free_dev: 1052 free_netdev(dev); 1053 failed: 1054 return err; 1055 } 1056 1057 static int tun_get_iff(struct net *net, struct tun_struct *tun, 1058 struct ifreq *ifr) 1059 { 1060 DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name); 1061 1062 strcpy(ifr->ifr_name, tun->dev->name); 1063 1064 ifr->ifr_flags = tun_flags(tun); 1065 1066 return 0; 1067 } 1068 1069 /* This is like a cut-down ethtool ops, except done via tun fd so no 1070 * privs required. */ 1071 static int set_offload(struct net_device *dev, unsigned long arg) 1072 { 1073 unsigned int old_features, features; 1074 1075 old_features = dev->features; 1076 /* Unset features, set them as we chew on the arg. */ 1077 features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST 1078 |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6 1079 |NETIF_F_UFO)); 1080 1081 if (arg & TUN_F_CSUM) { 1082 features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; 1083 arg &= ~TUN_F_CSUM; 1084 1085 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) { 1086 if (arg & TUN_F_TSO_ECN) { 1087 features |= NETIF_F_TSO_ECN; 1088 arg &= ~TUN_F_TSO_ECN; 1089 } 1090 if (arg & TUN_F_TSO4) 1091 features |= NETIF_F_TSO; 1092 if (arg & TUN_F_TSO6) 1093 features |= NETIF_F_TSO6; 1094 arg &= ~(TUN_F_TSO4|TUN_F_TSO6); 1095 } 1096 1097 if (arg & TUN_F_UFO) { 1098 features |= NETIF_F_UFO; 1099 arg &= ~TUN_F_UFO; 1100 } 1101 } 1102 1103 /* This gives the user a way to test for new features in future by 1104 * trying to set them. */ 1105 if (arg) 1106 return -EINVAL; 1107 1108 dev->features = features; 1109 if (old_features != dev->features) 1110 netdev_features_change(dev); 1111 1112 return 0; 1113 } 1114 1115 static long tun_chr_ioctl(struct file *file, unsigned int cmd, 1116 unsigned long arg) 1117 { 1118 struct tun_file *tfile = file->private_data; 1119 struct tun_struct *tun; 1120 void __user* argp = (void __user*)arg; 1121 struct ifreq ifr; 1122 int sndbuf; 1123 int ret; 1124 1125 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89) 1126 if (copy_from_user(&ifr, argp, sizeof ifr)) 1127 return -EFAULT; 1128 1129 if (cmd == TUNGETFEATURES) { 1130 /* Currently this just means: "what IFF flags are valid?". 1131 * This is needed because we never checked for invalid flags on 1132 * TUNSETIFF. */ 1133 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE | 1134 IFF_VNET_HDR, 1135 (unsigned int __user*)argp); 1136 } 1137 1138 rtnl_lock(); 1139 1140 tun = __tun_get(tfile); 1141 if (cmd == TUNSETIFF && !tun) { 1142 ifr.ifr_name[IFNAMSIZ-1] = '\0'; 1143 1144 ret = tun_set_iff(tfile->net, file, &ifr); 1145 1146 if (ret) 1147 goto unlock; 1148 1149 if (copy_to_user(argp, &ifr, sizeof(ifr))) 1150 ret = -EFAULT; 1151 goto unlock; 1152 } 1153 1154 ret = -EBADFD; 1155 if (!tun) 1156 goto unlock; 1157 1158 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd); 1159 1160 ret = 0; 1161 switch (cmd) { 1162 case TUNGETIFF: 1163 ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr); 1164 if (ret) 1165 break; 1166 1167 if (copy_to_user(argp, &ifr, sizeof(ifr))) 1168 ret = -EFAULT; 1169 break; 1170 1171 case TUNSETNOCSUM: 1172 /* Disable/Enable checksum */ 1173 if (arg) 1174 tun->flags |= TUN_NOCHECKSUM; 1175 else 1176 tun->flags &= ~TUN_NOCHECKSUM; 1177 1178 DBG(KERN_INFO "%s: checksum %s\n", 1179 tun->dev->name, arg ? "disabled" : "enabled"); 1180 break; 1181 1182 case TUNSETPERSIST: 1183 /* Disable/Enable persist mode */ 1184 if (arg) 1185 tun->flags |= TUN_PERSIST; 1186 else 1187 tun->flags &= ~TUN_PERSIST; 1188 1189 DBG(KERN_INFO "%s: persist %s\n", 1190 tun->dev->name, arg ? "enabled" : "disabled"); 1191 break; 1192 1193 case TUNSETOWNER: 1194 /* Set owner of the device */ 1195 tun->owner = (uid_t) arg; 1196 1197 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner); 1198 break; 1199 1200 case TUNSETGROUP: 1201 /* Set group of the device */ 1202 tun->group= (gid_t) arg; 1203 1204 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group); 1205 break; 1206 1207 case TUNSETLINK: 1208 /* Only allow setting the type when the interface is down */ 1209 if (tun->dev->flags & IFF_UP) { 1210 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n", 1211 tun->dev->name); 1212 ret = -EBUSY; 1213 } else { 1214 tun->dev->type = (int) arg; 1215 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type); 1216 ret = 0; 1217 } 1218 break; 1219 1220 #ifdef TUN_DEBUG 1221 case TUNSETDEBUG: 1222 tun->debug = arg; 1223 break; 1224 #endif 1225 case TUNSETOFFLOAD: 1226 ret = set_offload(tun->dev, arg); 1227 break; 1228 1229 case TUNSETTXFILTER: 1230 /* Can be set only for TAPs */ 1231 ret = -EINVAL; 1232 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) 1233 break; 1234 ret = update_filter(&tun->txflt, (void __user *)arg); 1235 break; 1236 1237 case SIOCGIFHWADDR: 1238 /* Get hw addres */ 1239 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN); 1240 ifr.ifr_hwaddr.sa_family = tun->dev->type; 1241 if (copy_to_user(argp, &ifr, sizeof ifr)) 1242 ret = -EFAULT; 1243 break; 1244 1245 case SIOCSIFHWADDR: 1246 /* Set hw address */ 1247 DBG(KERN_DEBUG "%s: set hw address: %pM\n", 1248 tun->dev->name, ifr.ifr_hwaddr.sa_data); 1249 1250 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr); 1251 break; 1252 1253 case TUNGETSNDBUF: 1254 sndbuf = tun->socket.sk->sk_sndbuf; 1255 if (copy_to_user(argp, &sndbuf, sizeof(sndbuf))) 1256 ret = -EFAULT; 1257 break; 1258 1259 case TUNSETSNDBUF: 1260 if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) { 1261 ret = -EFAULT; 1262 break; 1263 } 1264 1265 tun->socket.sk->sk_sndbuf = sndbuf; 1266 break; 1267 1268 default: 1269 ret = -EINVAL; 1270 break; 1271 }; 1272 1273 unlock: 1274 rtnl_unlock(); 1275 if (tun) 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->socket.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 .unlocked_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 .nodename = "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