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 * Brian Braunstein <linuxkernel@bristyle.com> 2007/03/23 22 * Fixed hw address handling. Now net_device.dev_addr is kept consistent 23 * with tun.dev_addr when the address is set by this module. 24 * 25 * Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14 26 * Add TUNSETLINK ioctl to set the link encapsulation 27 * 28 * Mark Smith <markzzzsmith@yahoo.com.au> 29 * Use random_ether_addr() for tap MAC address. 30 * 31 * Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20 32 * Fixes in packet dropping, queue length setting and queue wakeup. 33 * Increased default tx queue length. 34 * Added ethtool API. 35 * Minor cleanups 36 * 37 * Daniel Podlejski <underley@underley.eu.org> 38 * Modifications for 2.3.99-pre5 kernel. 39 */ 40 41 #define DRV_NAME "tun" 42 #define DRV_VERSION "1.6" 43 #define DRV_DESCRIPTION "Universal TUN/TAP device driver" 44 #define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>" 45 46 #include <linux/module.h> 47 #include <linux/errno.h> 48 #include <linux/kernel.h> 49 #include <linux/major.h> 50 #include <linux/slab.h> 51 #include <linux/poll.h> 52 #include <linux/fcntl.h> 53 #include <linux/init.h> 54 #include <linux/skbuff.h> 55 #include <linux/netdevice.h> 56 #include <linux/etherdevice.h> 57 #include <linux/miscdevice.h> 58 #include <linux/ethtool.h> 59 #include <linux/rtnetlink.h> 60 #include <linux/if.h> 61 #include <linux/if_arp.h> 62 #include <linux/if_ether.h> 63 #include <linux/if_tun.h> 64 #include <linux/crc32.h> 65 #include <net/net_namespace.h> 66 67 #include <asm/system.h> 68 #include <asm/uaccess.h> 69 70 #ifdef TUN_DEBUG 71 static int debug; 72 #endif 73 74 /* Network device part of the driver */ 75 76 static LIST_HEAD(tun_dev_list); 77 static const struct ethtool_ops tun_ethtool_ops; 78 79 /* Net device open. */ 80 static int tun_net_open(struct net_device *dev) 81 { 82 netif_start_queue(dev); 83 return 0; 84 } 85 86 /* Net device close. */ 87 static int tun_net_close(struct net_device *dev) 88 { 89 netif_stop_queue(dev); 90 return 0; 91 } 92 93 /* Net device start xmit */ 94 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev) 95 { 96 struct tun_struct *tun = netdev_priv(dev); 97 98 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len); 99 100 /* Drop packet if interface is not attached */ 101 if (!tun->attached) 102 goto drop; 103 104 /* Packet dropping */ 105 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) { 106 if (!(tun->flags & TUN_ONE_QUEUE)) { 107 /* Normal queueing mode. */ 108 /* Packet scheduler handles dropping of further packets. */ 109 netif_stop_queue(dev); 110 111 /* We won't see all dropped packets individually, so overrun 112 * error is more appropriate. */ 113 dev->stats.tx_fifo_errors++; 114 } else { 115 /* Single queue mode. 116 * Driver handles dropping of all packets itself. */ 117 goto drop; 118 } 119 } 120 121 /* Queue packet */ 122 skb_queue_tail(&tun->readq, skb); 123 dev->trans_start = jiffies; 124 125 /* Notify and wake up reader process */ 126 if (tun->flags & TUN_FASYNC) 127 kill_fasync(&tun->fasync, SIGIO, POLL_IN); 128 wake_up_interruptible(&tun->read_wait); 129 return 0; 130 131 drop: 132 dev->stats.tx_dropped++; 133 kfree_skb(skb); 134 return 0; 135 } 136 137 /** Add the specified Ethernet address to this multicast filter. */ 138 static void 139 add_multi(u32* filter, const u8* addr) 140 { 141 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26; 142 filter[bit_nr >> 5] |= 1 << (bit_nr & 31); 143 } 144 145 /** Remove the specified Ethernet addres from this multicast filter. */ 146 static void 147 del_multi(u32* filter, const u8* addr) 148 { 149 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26; 150 filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31)); 151 } 152 153 /** Update the list of multicast groups to which the network device belongs. 154 * This list is used to filter packets being sent from the character device to 155 * the network device. */ 156 static void 157 tun_net_mclist(struct net_device *dev) 158 { 159 struct tun_struct *tun = netdev_priv(dev); 160 const struct dev_mc_list *mclist; 161 int i; 162 DECLARE_MAC_BUF(mac); 163 DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n", 164 dev->name, dev->mc_count); 165 memset(tun->chr_filter, 0, sizeof tun->chr_filter); 166 for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL; 167 i++, mclist = mclist->next) { 168 add_multi(tun->net_filter, mclist->dmi_addr); 169 DBG(KERN_DEBUG "%s: tun_net_mclist: %s\n", 170 dev->name, print_mac(mac, mclist->dmi_addr)); 171 } 172 } 173 174 #define MIN_MTU 68 175 #define MAX_MTU 65535 176 177 static int 178 tun_net_change_mtu(struct net_device *dev, int new_mtu) 179 { 180 if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU) 181 return -EINVAL; 182 dev->mtu = new_mtu; 183 return 0; 184 } 185 186 /* Initialize net device. */ 187 static void tun_net_init(struct net_device *dev) 188 { 189 struct tun_struct *tun = netdev_priv(dev); 190 191 switch (tun->flags & TUN_TYPE_MASK) { 192 case TUN_TUN_DEV: 193 /* Point-to-Point TUN Device */ 194 dev->hard_header_len = 0; 195 dev->addr_len = 0; 196 dev->mtu = 1500; 197 dev->change_mtu = tun_net_change_mtu; 198 199 /* Zero header length */ 200 dev->type = ARPHRD_NONE; 201 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; 202 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 203 break; 204 205 case TUN_TAP_DEV: 206 /* Ethernet TAP Device */ 207 dev->set_multicast_list = tun_net_mclist; 208 209 ether_setup(dev); 210 dev->change_mtu = tun_net_change_mtu; 211 212 /* random address already created for us by tun_set_iff, use it */ 213 memcpy(dev->dev_addr, tun->dev_addr, min(sizeof(tun->dev_addr), sizeof(dev->dev_addr)) ); 214 215 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 216 break; 217 } 218 } 219 220 /* Character device part */ 221 222 /* Poll */ 223 static unsigned int tun_chr_poll(struct file *file, poll_table * wait) 224 { 225 struct tun_struct *tun = file->private_data; 226 unsigned int mask = POLLOUT | POLLWRNORM; 227 228 if (!tun) 229 return -EBADFD; 230 231 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name); 232 233 poll_wait(file, &tun->read_wait, wait); 234 235 if (!skb_queue_empty(&tun->readq)) 236 mask |= POLLIN | POLLRDNORM; 237 238 return mask; 239 } 240 241 /* Get packet from user space buffer */ 242 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count) 243 { 244 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) }; 245 struct sk_buff *skb; 246 size_t len = count, align = 0; 247 248 if (!(tun->flags & TUN_NO_PI)) { 249 if ((len -= sizeof(pi)) > count) 250 return -EINVAL; 251 252 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi))) 253 return -EFAULT; 254 } 255 256 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) 257 align = NET_IP_ALIGN; 258 259 if (!(skb = alloc_skb(len + align, GFP_KERNEL))) { 260 tun->dev->stats.rx_dropped++; 261 return -ENOMEM; 262 } 263 264 if (align) 265 skb_reserve(skb, align); 266 if (memcpy_fromiovec(skb_put(skb, len), iv, len)) { 267 tun->dev->stats.rx_dropped++; 268 kfree_skb(skb); 269 return -EFAULT; 270 } 271 272 switch (tun->flags & TUN_TYPE_MASK) { 273 case TUN_TUN_DEV: 274 skb_reset_mac_header(skb); 275 skb->protocol = pi.proto; 276 skb->dev = tun->dev; 277 break; 278 case TUN_TAP_DEV: 279 skb->protocol = eth_type_trans(skb, tun->dev); 280 break; 281 }; 282 283 if (tun->flags & TUN_NOCHECKSUM) 284 skb->ip_summed = CHECKSUM_UNNECESSARY; 285 286 netif_rx_ni(skb); 287 tun->dev->last_rx = jiffies; 288 289 tun->dev->stats.rx_packets++; 290 tun->dev->stats.rx_bytes += len; 291 292 return count; 293 } 294 295 static inline size_t iov_total(const struct iovec *iv, unsigned long count) 296 { 297 unsigned long i; 298 size_t len; 299 300 for (i = 0, len = 0; i < count; i++) 301 len += iv[i].iov_len; 302 303 return len; 304 } 305 306 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, 307 unsigned long count, loff_t pos) 308 { 309 struct tun_struct *tun = iocb->ki_filp->private_data; 310 311 if (!tun) 312 return -EBADFD; 313 314 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count); 315 316 return tun_get_user(tun, (struct iovec *) iv, iov_total(iv, count)); 317 } 318 319 /* Put packet to the user space buffer */ 320 static __inline__ ssize_t tun_put_user(struct tun_struct *tun, 321 struct sk_buff *skb, 322 struct iovec *iv, int len) 323 { 324 struct tun_pi pi = { 0, skb->protocol }; 325 ssize_t total = 0; 326 327 if (!(tun->flags & TUN_NO_PI)) { 328 if ((len -= sizeof(pi)) < 0) 329 return -EINVAL; 330 331 if (len < skb->len) { 332 /* Packet will be striped */ 333 pi.flags |= TUN_PKT_STRIP; 334 } 335 336 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi))) 337 return -EFAULT; 338 total += sizeof(pi); 339 } 340 341 len = min_t(int, skb->len, len); 342 343 skb_copy_datagram_iovec(skb, 0, iv, len); 344 total += len; 345 346 tun->dev->stats.tx_packets++; 347 tun->dev->stats.tx_bytes += len; 348 349 return total; 350 } 351 352 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv, 353 unsigned long count, loff_t pos) 354 { 355 struct file *file = iocb->ki_filp; 356 struct tun_struct *tun = file->private_data; 357 DECLARE_WAITQUEUE(wait, current); 358 struct sk_buff *skb; 359 ssize_t len, ret = 0; 360 DECLARE_MAC_BUF(mac); 361 362 if (!tun) 363 return -EBADFD; 364 365 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name); 366 367 len = iov_total(iv, count); 368 if (len < 0) 369 return -EINVAL; 370 371 add_wait_queue(&tun->read_wait, &wait); 372 while (len) { 373 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 374 u8 addr[ ETH_ALEN]; 375 int bit_nr; 376 377 current->state = TASK_INTERRUPTIBLE; 378 379 /* Read frames from the queue */ 380 if (!(skb=skb_dequeue(&tun->readq))) { 381 if (file->f_flags & O_NONBLOCK) { 382 ret = -EAGAIN; 383 break; 384 } 385 if (signal_pending(current)) { 386 ret = -ERESTARTSYS; 387 break; 388 } 389 390 /* Nothing to read, let's sleep */ 391 schedule(); 392 continue; 393 } 394 netif_wake_queue(tun->dev); 395 396 /** Decide whether to accept this packet. This code is designed to 397 * behave identically to an Ethernet interface. Accept the packet if 398 * - we are promiscuous. 399 * - the packet is addressed to us. 400 * - the packet is broadcast. 401 * - the packet is multicast and 402 * - we are multicast promiscous. 403 * - we belong to the multicast group. 404 */ 405 skb_copy_from_linear_data(skb, addr, min_t(size_t, sizeof addr, 406 skb->len)); 407 bit_nr = ether_crc(sizeof addr, addr) >> 26; 408 if ((tun->if_flags & IFF_PROMISC) || 409 memcmp(addr, tun->dev_addr, sizeof addr) == 0 || 410 memcmp(addr, ones, sizeof addr) == 0 || 411 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) || 412 (addr[0] == 0x33 && addr[1] == 0x33)) && 413 ((tun->if_flags & IFF_ALLMULTI) || 414 (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) { 415 DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %s\n", 416 tun->dev->name, print_mac(mac, addr)); 417 ret = tun_put_user(tun, skb, (struct iovec *) iv, len); 418 kfree_skb(skb); 419 break; 420 } else { 421 DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %s\n", 422 tun->dev->name, print_mac(mac, addr)); 423 kfree_skb(skb); 424 continue; 425 } 426 } 427 428 current->state = TASK_RUNNING; 429 remove_wait_queue(&tun->read_wait, &wait); 430 431 return ret; 432 } 433 434 static void tun_setup(struct net_device *dev) 435 { 436 struct tun_struct *tun = netdev_priv(dev); 437 438 skb_queue_head_init(&tun->readq); 439 init_waitqueue_head(&tun->read_wait); 440 441 tun->owner = -1; 442 tun->group = -1; 443 444 dev->open = tun_net_open; 445 dev->hard_start_xmit = tun_net_xmit; 446 dev->stop = tun_net_close; 447 dev->ethtool_ops = &tun_ethtool_ops; 448 dev->destructor = free_netdev; 449 } 450 451 static struct tun_struct *tun_get_by_name(const char *name) 452 { 453 struct tun_struct *tun; 454 455 ASSERT_RTNL(); 456 list_for_each_entry(tun, &tun_dev_list, list) { 457 if (!strncmp(tun->dev->name, name, IFNAMSIZ)) 458 return tun; 459 } 460 461 return NULL; 462 } 463 464 static int tun_set_iff(struct file *file, struct ifreq *ifr) 465 { 466 struct tun_struct *tun; 467 struct net_device *dev; 468 int err; 469 470 tun = tun_get_by_name(ifr->ifr_name); 471 if (tun) { 472 if (tun->attached) 473 return -EBUSY; 474 475 /* Check permissions */ 476 if (((tun->owner != -1 && 477 current->euid != tun->owner) || 478 (tun->group != -1 && 479 current->egid != tun->group)) && 480 !capable(CAP_NET_ADMIN)) 481 return -EPERM; 482 } 483 else if (__dev_get_by_name(&init_net, ifr->ifr_name)) 484 return -EINVAL; 485 else { 486 char *name; 487 unsigned long flags = 0; 488 489 err = -EINVAL; 490 491 if (!capable(CAP_NET_ADMIN)) 492 return -EPERM; 493 494 /* Set dev type */ 495 if (ifr->ifr_flags & IFF_TUN) { 496 /* TUN device */ 497 flags |= TUN_TUN_DEV; 498 name = "tun%d"; 499 } else if (ifr->ifr_flags & IFF_TAP) { 500 /* TAP device */ 501 flags |= TUN_TAP_DEV; 502 name = "tap%d"; 503 } else 504 goto failed; 505 506 if (*ifr->ifr_name) 507 name = ifr->ifr_name; 508 509 dev = alloc_netdev(sizeof(struct tun_struct), name, 510 tun_setup); 511 if (!dev) 512 return -ENOMEM; 513 514 tun = netdev_priv(dev); 515 tun->dev = dev; 516 tun->flags = flags; 517 /* Be promiscuous by default to maintain previous behaviour. */ 518 tun->if_flags = IFF_PROMISC; 519 /* Generate random Ethernet address. */ 520 *(u16 *)tun->dev_addr = htons(0x00FF); 521 get_random_bytes(tun->dev_addr + sizeof(u16), 4); 522 memset(tun->chr_filter, 0, sizeof tun->chr_filter); 523 524 tun_net_init(dev); 525 526 if (strchr(dev->name, '%')) { 527 err = dev_alloc_name(dev, dev->name); 528 if (err < 0) 529 goto err_free_dev; 530 } 531 532 err = register_netdevice(tun->dev); 533 if (err < 0) 534 goto err_free_dev; 535 536 list_add(&tun->list, &tun_dev_list); 537 } 538 539 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name); 540 541 if (ifr->ifr_flags & IFF_NO_PI) 542 tun->flags |= TUN_NO_PI; 543 544 if (ifr->ifr_flags & IFF_ONE_QUEUE) 545 tun->flags |= TUN_ONE_QUEUE; 546 547 file->private_data = tun; 548 tun->attached = 1; 549 550 strcpy(ifr->ifr_name, tun->dev->name); 551 return 0; 552 553 err_free_dev: 554 free_netdev(dev); 555 failed: 556 return err; 557 } 558 559 static int tun_chr_ioctl(struct inode *inode, struct file *file, 560 unsigned int cmd, unsigned long arg) 561 { 562 struct tun_struct *tun = file->private_data; 563 void __user* argp = (void __user*)arg; 564 struct ifreq ifr; 565 DECLARE_MAC_BUF(mac); 566 567 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89) 568 if (copy_from_user(&ifr, argp, sizeof ifr)) 569 return -EFAULT; 570 571 if (cmd == TUNSETIFF && !tun) { 572 int err; 573 574 ifr.ifr_name[IFNAMSIZ-1] = '\0'; 575 576 rtnl_lock(); 577 err = tun_set_iff(file, &ifr); 578 rtnl_unlock(); 579 580 if (err) 581 return err; 582 583 if (copy_to_user(argp, &ifr, sizeof(ifr))) 584 return -EFAULT; 585 return 0; 586 } 587 588 if (!tun) 589 return -EBADFD; 590 591 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd); 592 593 switch (cmd) { 594 case TUNSETNOCSUM: 595 /* Disable/Enable checksum */ 596 if (arg) 597 tun->flags |= TUN_NOCHECKSUM; 598 else 599 tun->flags &= ~TUN_NOCHECKSUM; 600 601 DBG(KERN_INFO "%s: checksum %s\n", 602 tun->dev->name, arg ? "disabled" : "enabled"); 603 break; 604 605 case TUNSETPERSIST: 606 /* Disable/Enable persist mode */ 607 if (arg) 608 tun->flags |= TUN_PERSIST; 609 else 610 tun->flags &= ~TUN_PERSIST; 611 612 DBG(KERN_INFO "%s: persist %s\n", 613 tun->dev->name, arg ? "disabled" : "enabled"); 614 break; 615 616 case TUNSETOWNER: 617 /* Set owner of the device */ 618 tun->owner = (uid_t) arg; 619 620 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner); 621 break; 622 623 case TUNSETGROUP: 624 /* Set group of the device */ 625 tun->group= (gid_t) arg; 626 627 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group); 628 break; 629 630 case TUNSETLINK: 631 /* Only allow setting the type when the interface is down */ 632 if (tun->dev->flags & IFF_UP) { 633 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n", 634 tun->dev->name); 635 return -EBUSY; 636 } else { 637 tun->dev->type = (int) arg; 638 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type); 639 } 640 break; 641 642 #ifdef TUN_DEBUG 643 case TUNSETDEBUG: 644 tun->debug = arg; 645 break; 646 #endif 647 648 case SIOCGIFFLAGS: 649 ifr.ifr_flags = tun->if_flags; 650 if (copy_to_user( argp, &ifr, sizeof ifr)) 651 return -EFAULT; 652 return 0; 653 654 case SIOCSIFFLAGS: 655 /** Set the character device's interface flags. Currently only 656 * IFF_PROMISC and IFF_ALLMULTI are used. */ 657 tun->if_flags = ifr.ifr_flags; 658 DBG(KERN_INFO "%s: interface flags 0x%lx\n", 659 tun->dev->name, tun->if_flags); 660 return 0; 661 662 case SIOCGIFHWADDR: 663 /* Note: the actual net device's address may be different */ 664 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr, 665 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr)); 666 if (copy_to_user( argp, &ifr, sizeof ifr)) 667 return -EFAULT; 668 return 0; 669 670 case SIOCSIFHWADDR: 671 { 672 /* try to set the actual net device's hw address */ 673 int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr); 674 675 if (ret == 0) { 676 /** Set the character device's hardware address. This is used when 677 * filtering packets being sent from the network device to the character 678 * device. */ 679 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data, 680 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr)); 681 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n", 682 tun->dev->name, 683 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2], 684 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]); 685 } 686 687 return ret; 688 } 689 690 case SIOCADDMULTI: 691 /** Add the specified group to the character device's multicast filter 692 * list. */ 693 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data); 694 DBG(KERN_DEBUG "%s: add multi: %s\n", 695 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data)); 696 return 0; 697 698 case SIOCDELMULTI: 699 /** Remove the specified group from the character device's multicast 700 * filter list. */ 701 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data); 702 DBG(KERN_DEBUG "%s: del multi: %s\n", 703 tun->dev->name, print_mac(mac, ifr.ifr_hwaddr.sa_data)); 704 return 0; 705 706 default: 707 return -EINVAL; 708 }; 709 710 return 0; 711 } 712 713 static int tun_chr_fasync(int fd, struct file *file, int on) 714 { 715 struct tun_struct *tun = file->private_data; 716 int ret; 717 718 if (!tun) 719 return -EBADFD; 720 721 DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on); 722 723 if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0) 724 return ret; 725 726 if (on) { 727 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0); 728 if (ret) 729 return ret; 730 tun->flags |= TUN_FASYNC; 731 } else 732 tun->flags &= ~TUN_FASYNC; 733 734 return 0; 735 } 736 737 static int tun_chr_open(struct inode *inode, struct file * file) 738 { 739 DBG1(KERN_INFO "tunX: tun_chr_open\n"); 740 file->private_data = NULL; 741 return 0; 742 } 743 744 static int tun_chr_close(struct inode *inode, struct file *file) 745 { 746 struct tun_struct *tun = file->private_data; 747 748 if (!tun) 749 return 0; 750 751 DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name); 752 753 tun_chr_fasync(-1, file, 0); 754 755 rtnl_lock(); 756 757 /* Detach from net device */ 758 file->private_data = NULL; 759 tun->attached = 0; 760 761 /* Drop read queue */ 762 skb_queue_purge(&tun->readq); 763 764 if (!(tun->flags & TUN_PERSIST)) { 765 list_del(&tun->list); 766 unregister_netdevice(tun->dev); 767 } 768 769 rtnl_unlock(); 770 771 return 0; 772 } 773 774 static const struct file_operations tun_fops = { 775 .owner = THIS_MODULE, 776 .llseek = no_llseek, 777 .read = do_sync_read, 778 .aio_read = tun_chr_aio_read, 779 .write = do_sync_write, 780 .aio_write = tun_chr_aio_write, 781 .poll = tun_chr_poll, 782 .ioctl = tun_chr_ioctl, 783 .open = tun_chr_open, 784 .release = tun_chr_close, 785 .fasync = tun_chr_fasync 786 }; 787 788 static struct miscdevice tun_miscdev = { 789 .minor = TUN_MINOR, 790 .name = "tun", 791 .fops = &tun_fops, 792 }; 793 794 /* ethtool interface */ 795 796 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) 797 { 798 cmd->supported = 0; 799 cmd->advertising = 0; 800 cmd->speed = SPEED_10; 801 cmd->duplex = DUPLEX_FULL; 802 cmd->port = PORT_TP; 803 cmd->phy_address = 0; 804 cmd->transceiver = XCVR_INTERNAL; 805 cmd->autoneg = AUTONEG_DISABLE; 806 cmd->maxtxpkt = 0; 807 cmd->maxrxpkt = 0; 808 return 0; 809 } 810 811 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) 812 { 813 struct tun_struct *tun = netdev_priv(dev); 814 815 strcpy(info->driver, DRV_NAME); 816 strcpy(info->version, DRV_VERSION); 817 strcpy(info->fw_version, "N/A"); 818 819 switch (tun->flags & TUN_TYPE_MASK) { 820 case TUN_TUN_DEV: 821 strcpy(info->bus_info, "tun"); 822 break; 823 case TUN_TAP_DEV: 824 strcpy(info->bus_info, "tap"); 825 break; 826 } 827 } 828 829 static u32 tun_get_msglevel(struct net_device *dev) 830 { 831 #ifdef TUN_DEBUG 832 struct tun_struct *tun = netdev_priv(dev); 833 return tun->debug; 834 #else 835 return -EOPNOTSUPP; 836 #endif 837 } 838 839 static void tun_set_msglevel(struct net_device *dev, u32 value) 840 { 841 #ifdef TUN_DEBUG 842 struct tun_struct *tun = netdev_priv(dev); 843 tun->debug = value; 844 #endif 845 } 846 847 static u32 tun_get_link(struct net_device *dev) 848 { 849 struct tun_struct *tun = netdev_priv(dev); 850 return tun->attached; 851 } 852 853 static u32 tun_get_rx_csum(struct net_device *dev) 854 { 855 struct tun_struct *tun = netdev_priv(dev); 856 return (tun->flags & TUN_NOCHECKSUM) == 0; 857 } 858 859 static int tun_set_rx_csum(struct net_device *dev, u32 data) 860 { 861 struct tun_struct *tun = netdev_priv(dev); 862 if (data) 863 tun->flags &= ~TUN_NOCHECKSUM; 864 else 865 tun->flags |= TUN_NOCHECKSUM; 866 return 0; 867 } 868 869 static const struct ethtool_ops tun_ethtool_ops = { 870 .get_settings = tun_get_settings, 871 .get_drvinfo = tun_get_drvinfo, 872 .get_msglevel = tun_get_msglevel, 873 .set_msglevel = tun_set_msglevel, 874 .get_link = tun_get_link, 875 .get_rx_csum = tun_get_rx_csum, 876 .set_rx_csum = tun_set_rx_csum 877 }; 878 879 static int __init tun_init(void) 880 { 881 int ret = 0; 882 883 printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION); 884 printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT); 885 886 ret = misc_register(&tun_miscdev); 887 if (ret) 888 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR); 889 return ret; 890 } 891 892 static void tun_cleanup(void) 893 { 894 struct tun_struct *tun, *nxt; 895 896 misc_deregister(&tun_miscdev); 897 898 rtnl_lock(); 899 list_for_each_entry_safe(tun, nxt, &tun_dev_list, list) { 900 DBG(KERN_INFO "%s cleaned up\n", tun->dev->name); 901 unregister_netdevice(tun->dev); 902 } 903 rtnl_unlock(); 904 905 } 906 907 module_init(tun_init); 908 module_exit(tun_cleanup); 909 MODULE_DESCRIPTION(DRV_DESCRIPTION); 910 MODULE_AUTHOR(DRV_COPYRIGHT); 911 MODULE_LICENSE("GPL"); 912 MODULE_ALIAS_MISCDEV(TUN_MINOR); 913