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 66 #include <asm/system.h> 67 #include <asm/uaccess.h> 68 69 #ifdef TUN_DEBUG 70 static int debug; 71 #endif 72 73 /* Network device part of the driver */ 74 75 static LIST_HEAD(tun_dev_list); 76 static const struct ethtool_ops tun_ethtool_ops; 77 78 /* Net device open. */ 79 static int tun_net_open(struct net_device *dev) 80 { 81 netif_start_queue(dev); 82 return 0; 83 } 84 85 /* Net device close. */ 86 static int tun_net_close(struct net_device *dev) 87 { 88 netif_stop_queue(dev); 89 return 0; 90 } 91 92 /* Net device start xmit */ 93 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev) 94 { 95 struct tun_struct *tun = netdev_priv(dev); 96 97 DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len); 98 99 /* Drop packet if interface is not attached */ 100 if (!tun->attached) 101 goto drop; 102 103 /* Packet dropping */ 104 if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) { 105 if (!(tun->flags & TUN_ONE_QUEUE)) { 106 /* Normal queueing mode. */ 107 /* Packet scheduler handles dropping of further packets. */ 108 netif_stop_queue(dev); 109 110 /* We won't see all dropped packets individually, so overrun 111 * error is more appropriate. */ 112 tun->stats.tx_fifo_errors++; 113 } else { 114 /* Single queue mode. 115 * Driver handles dropping of all packets itself. */ 116 goto drop; 117 } 118 } 119 120 /* Queue packet */ 121 skb_queue_tail(&tun->readq, skb); 122 dev->trans_start = jiffies; 123 124 /* Notify and wake up reader process */ 125 if (tun->flags & TUN_FASYNC) 126 kill_fasync(&tun->fasync, SIGIO, POLL_IN); 127 wake_up_interruptible(&tun->read_wait); 128 return 0; 129 130 drop: 131 tun->stats.tx_dropped++; 132 kfree_skb(skb); 133 return 0; 134 } 135 136 /** Add the specified Ethernet address to this multicast filter. */ 137 static void 138 add_multi(u32* filter, const u8* addr) 139 { 140 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26; 141 filter[bit_nr >> 5] |= 1 << (bit_nr & 31); 142 } 143 144 /** Remove the specified Ethernet addres from this multicast filter. */ 145 static void 146 del_multi(u32* filter, const u8* addr) 147 { 148 int bit_nr = ether_crc(ETH_ALEN, addr) >> 26; 149 filter[bit_nr >> 5] &= ~(1 << (bit_nr & 31)); 150 } 151 152 /** Update the list of multicast groups to which the network device belongs. 153 * This list is used to filter packets being sent from the character device to 154 * the network device. */ 155 static void 156 tun_net_mclist(struct net_device *dev) 157 { 158 struct tun_struct *tun = netdev_priv(dev); 159 const struct dev_mc_list *mclist; 160 int i; 161 DBG(KERN_DEBUG "%s: tun_net_mclist: mc_count %d\n", 162 dev->name, dev->mc_count); 163 memset(tun->chr_filter, 0, sizeof tun->chr_filter); 164 for (i = 0, mclist = dev->mc_list; i < dev->mc_count && mclist != NULL; 165 i++, mclist = mclist->next) { 166 add_multi(tun->net_filter, mclist->dmi_addr); 167 DBG(KERN_DEBUG "%s: tun_net_mclist: %x:%x:%x:%x:%x:%x\n", 168 dev->name, 169 mclist->dmi_addr[0], mclist->dmi_addr[1], mclist->dmi_addr[2], 170 mclist->dmi_addr[3], mclist->dmi_addr[4], mclist->dmi_addr[5]); 171 } 172 } 173 174 static struct net_device_stats *tun_net_stats(struct net_device *dev) 175 { 176 struct tun_struct *tun = netdev_priv(dev); 177 return &tun->stats; 178 } 179 180 /* Initialize net device. */ 181 static void tun_net_init(struct net_device *dev) 182 { 183 struct tun_struct *tun = netdev_priv(dev); 184 185 switch (tun->flags & TUN_TYPE_MASK) { 186 case TUN_TUN_DEV: 187 /* Point-to-Point TUN Device */ 188 dev->hard_header_len = 0; 189 dev->addr_len = 0; 190 dev->mtu = 1500; 191 192 /* Zero header length */ 193 dev->type = ARPHRD_NONE; 194 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; 195 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 196 break; 197 198 case TUN_TAP_DEV: 199 /* Ethernet TAP Device */ 200 dev->set_multicast_list = tun_net_mclist; 201 202 ether_setup(dev); 203 204 /* random address already created for us by tun_set_iff, use it */ 205 memcpy(dev->dev_addr, tun->dev_addr, min(sizeof(tun->dev_addr), sizeof(dev->dev_addr)) ); 206 207 dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ 208 break; 209 } 210 } 211 212 /* Character device part */ 213 214 /* Poll */ 215 static unsigned int tun_chr_poll(struct file *file, poll_table * wait) 216 { 217 struct tun_struct *tun = file->private_data; 218 unsigned int mask = POLLOUT | POLLWRNORM; 219 220 if (!tun) 221 return -EBADFD; 222 223 DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name); 224 225 poll_wait(file, &tun->read_wait, wait); 226 227 if (!skb_queue_empty(&tun->readq)) 228 mask |= POLLIN | POLLRDNORM; 229 230 return mask; 231 } 232 233 /* Get packet from user space buffer */ 234 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count) 235 { 236 struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) }; 237 struct sk_buff *skb; 238 size_t len = count, align = 0; 239 240 if (!(tun->flags & TUN_NO_PI)) { 241 if ((len -= sizeof(pi)) > count) 242 return -EINVAL; 243 244 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi))) 245 return -EFAULT; 246 } 247 248 if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) 249 align = NET_IP_ALIGN; 250 251 if (!(skb = alloc_skb(len + align, GFP_KERNEL))) { 252 tun->stats.rx_dropped++; 253 return -ENOMEM; 254 } 255 256 if (align) 257 skb_reserve(skb, align); 258 if (memcpy_fromiovec(skb_put(skb, len), iv, len)) { 259 tun->stats.rx_dropped++; 260 kfree_skb(skb); 261 return -EFAULT; 262 } 263 264 switch (tun->flags & TUN_TYPE_MASK) { 265 case TUN_TUN_DEV: 266 skb_reset_mac_header(skb); 267 skb->protocol = pi.proto; 268 skb->dev = tun->dev; 269 break; 270 case TUN_TAP_DEV: 271 skb->protocol = eth_type_trans(skb, tun->dev); 272 break; 273 }; 274 275 if (tun->flags & TUN_NOCHECKSUM) 276 skb->ip_summed = CHECKSUM_UNNECESSARY; 277 278 netif_rx_ni(skb); 279 tun->dev->last_rx = jiffies; 280 281 tun->stats.rx_packets++; 282 tun->stats.rx_bytes += len; 283 284 return count; 285 } 286 287 static inline size_t iov_total(const struct iovec *iv, unsigned long count) 288 { 289 unsigned long i; 290 size_t len; 291 292 for (i = 0, len = 0; i < count; i++) 293 len += iv[i].iov_len; 294 295 return len; 296 } 297 298 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, 299 unsigned long count, loff_t pos) 300 { 301 struct tun_struct *tun = iocb->ki_filp->private_data; 302 303 if (!tun) 304 return -EBADFD; 305 306 DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count); 307 308 return tun_get_user(tun, (struct iovec *) iv, iov_total(iv, count)); 309 } 310 311 /* Put packet to the user space buffer */ 312 static __inline__ ssize_t tun_put_user(struct tun_struct *tun, 313 struct sk_buff *skb, 314 struct iovec *iv, int len) 315 { 316 struct tun_pi pi = { 0, skb->protocol }; 317 ssize_t total = 0; 318 319 if (!(tun->flags & TUN_NO_PI)) { 320 if ((len -= sizeof(pi)) < 0) 321 return -EINVAL; 322 323 if (len < skb->len) { 324 /* Packet will be striped */ 325 pi.flags |= TUN_PKT_STRIP; 326 } 327 328 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi))) 329 return -EFAULT; 330 total += sizeof(pi); 331 } 332 333 len = min_t(int, skb->len, len); 334 335 skb_copy_datagram_iovec(skb, 0, iv, len); 336 total += len; 337 338 tun->stats.tx_packets++; 339 tun->stats.tx_bytes += len; 340 341 return total; 342 } 343 344 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv, 345 unsigned long count, loff_t pos) 346 { 347 struct file *file = iocb->ki_filp; 348 struct tun_struct *tun = file->private_data; 349 DECLARE_WAITQUEUE(wait, current); 350 struct sk_buff *skb; 351 ssize_t len, ret = 0; 352 353 if (!tun) 354 return -EBADFD; 355 356 DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name); 357 358 len = iov_total(iv, count); 359 if (len < 0) 360 return -EINVAL; 361 362 add_wait_queue(&tun->read_wait, &wait); 363 while (len) { 364 const u8 ones[ ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 365 u8 addr[ ETH_ALEN]; 366 int bit_nr; 367 368 current->state = TASK_INTERRUPTIBLE; 369 370 /* Read frames from the queue */ 371 if (!(skb=skb_dequeue(&tun->readq))) { 372 if (file->f_flags & O_NONBLOCK) { 373 ret = -EAGAIN; 374 break; 375 } 376 if (signal_pending(current)) { 377 ret = -ERESTARTSYS; 378 break; 379 } 380 381 /* Nothing to read, let's sleep */ 382 schedule(); 383 continue; 384 } 385 netif_wake_queue(tun->dev); 386 387 /** Decide whether to accept this packet. This code is designed to 388 * behave identically to an Ethernet interface. Accept the packet if 389 * - we are promiscuous. 390 * - the packet is addressed to us. 391 * - the packet is broadcast. 392 * - the packet is multicast and 393 * - we are multicast promiscous. 394 * - we belong to the multicast group. 395 */ 396 skb_copy_from_linear_data(skb, addr, min_t(size_t, sizeof addr, 397 skb->len)); 398 bit_nr = ether_crc(sizeof addr, addr) >> 26; 399 if ((tun->if_flags & IFF_PROMISC) || 400 memcmp(addr, tun->dev_addr, sizeof addr) == 0 || 401 memcmp(addr, ones, sizeof addr) == 0 || 402 (((addr[0] == 1 && addr[1] == 0 && addr[2] == 0x5e) || 403 (addr[0] == 0x33 && addr[1] == 0x33)) && 404 ((tun->if_flags & IFF_ALLMULTI) || 405 (tun->chr_filter[bit_nr >> 5] & (1 << (bit_nr & 31)))))) { 406 DBG(KERN_DEBUG "%s: tun_chr_readv: accepted: %x:%x:%x:%x:%x:%x\n", 407 tun->dev->name, addr[0], addr[1], addr[2], 408 addr[3], addr[4], addr[5]); 409 ret = tun_put_user(tun, skb, (struct iovec *) iv, len); 410 kfree_skb(skb); 411 break; 412 } else { 413 DBG(KERN_DEBUG "%s: tun_chr_readv: rejected: %x:%x:%x:%x:%x:%x\n", 414 tun->dev->name, addr[0], addr[1], addr[2], 415 addr[3], addr[4], addr[5]); 416 kfree_skb(skb); 417 continue; 418 } 419 } 420 421 current->state = TASK_RUNNING; 422 remove_wait_queue(&tun->read_wait, &wait); 423 424 return ret; 425 } 426 427 static void tun_setup(struct net_device *dev) 428 { 429 struct tun_struct *tun = netdev_priv(dev); 430 431 skb_queue_head_init(&tun->readq); 432 init_waitqueue_head(&tun->read_wait); 433 434 tun->owner = -1; 435 tun->group = -1; 436 437 SET_MODULE_OWNER(dev); 438 dev->open = tun_net_open; 439 dev->hard_start_xmit = tun_net_xmit; 440 dev->stop = tun_net_close; 441 dev->get_stats = tun_net_stats; 442 dev->ethtool_ops = &tun_ethtool_ops; 443 dev->destructor = free_netdev; 444 } 445 446 static struct tun_struct *tun_get_by_name(const char *name) 447 { 448 struct tun_struct *tun; 449 450 ASSERT_RTNL(); 451 list_for_each_entry(tun, &tun_dev_list, list) { 452 if (!strncmp(tun->dev->name, name, IFNAMSIZ)) 453 return tun; 454 } 455 456 return NULL; 457 } 458 459 static int tun_set_iff(struct file *file, struct ifreq *ifr) 460 { 461 struct tun_struct *tun; 462 struct net_device *dev; 463 int err; 464 465 tun = tun_get_by_name(ifr->ifr_name); 466 if (tun) { 467 if (tun->attached) 468 return -EBUSY; 469 470 /* Check permissions */ 471 if (((tun->owner != -1 && 472 current->euid != tun->owner) || 473 (tun->group != -1 && 474 current->egid != tun->group)) && 475 !capable(CAP_NET_ADMIN)) 476 return -EPERM; 477 } 478 else if (__dev_get_by_name(ifr->ifr_name)) 479 return -EINVAL; 480 else { 481 char *name; 482 unsigned long flags = 0; 483 484 err = -EINVAL; 485 486 if (!capable(CAP_NET_ADMIN)) 487 return -EPERM; 488 489 /* Set dev type */ 490 if (ifr->ifr_flags & IFF_TUN) { 491 /* TUN device */ 492 flags |= TUN_TUN_DEV; 493 name = "tun%d"; 494 } else if (ifr->ifr_flags & IFF_TAP) { 495 /* TAP device */ 496 flags |= TUN_TAP_DEV; 497 name = "tap%d"; 498 } else 499 goto failed; 500 501 if (*ifr->ifr_name) 502 name = ifr->ifr_name; 503 504 dev = alloc_netdev(sizeof(struct tun_struct), name, 505 tun_setup); 506 if (!dev) 507 return -ENOMEM; 508 509 tun = netdev_priv(dev); 510 tun->dev = dev; 511 tun->flags = flags; 512 /* Be promiscuous by default to maintain previous behaviour. */ 513 tun->if_flags = IFF_PROMISC; 514 /* Generate random Ethernet address. */ 515 *(u16 *)tun->dev_addr = htons(0x00FF); 516 get_random_bytes(tun->dev_addr + sizeof(u16), 4); 517 memset(tun->chr_filter, 0, sizeof tun->chr_filter); 518 519 tun_net_init(dev); 520 521 if (strchr(dev->name, '%')) { 522 err = dev_alloc_name(dev, dev->name); 523 if (err < 0) 524 goto err_free_dev; 525 } 526 527 err = register_netdevice(tun->dev); 528 if (err < 0) 529 goto err_free_dev; 530 531 list_add(&tun->list, &tun_dev_list); 532 } 533 534 DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name); 535 536 if (ifr->ifr_flags & IFF_NO_PI) 537 tun->flags |= TUN_NO_PI; 538 539 if (ifr->ifr_flags & IFF_ONE_QUEUE) 540 tun->flags |= TUN_ONE_QUEUE; 541 542 file->private_data = tun; 543 tun->attached = 1; 544 545 strcpy(ifr->ifr_name, tun->dev->name); 546 return 0; 547 548 err_free_dev: 549 free_netdev(dev); 550 failed: 551 return err; 552 } 553 554 static int tun_chr_ioctl(struct inode *inode, struct file *file, 555 unsigned int cmd, unsigned long arg) 556 { 557 struct tun_struct *tun = file->private_data; 558 void __user* argp = (void __user*)arg; 559 struct ifreq ifr; 560 561 if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89) 562 if (copy_from_user(&ifr, argp, sizeof ifr)) 563 return -EFAULT; 564 565 if (cmd == TUNSETIFF && !tun) { 566 int err; 567 568 ifr.ifr_name[IFNAMSIZ-1] = '\0'; 569 570 rtnl_lock(); 571 err = tun_set_iff(file, &ifr); 572 rtnl_unlock(); 573 574 if (err) 575 return err; 576 577 if (copy_to_user(argp, &ifr, sizeof(ifr))) 578 return -EFAULT; 579 return 0; 580 } 581 582 if (!tun) 583 return -EBADFD; 584 585 DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd); 586 587 switch (cmd) { 588 case TUNSETNOCSUM: 589 /* Disable/Enable checksum */ 590 if (arg) 591 tun->flags |= TUN_NOCHECKSUM; 592 else 593 tun->flags &= ~TUN_NOCHECKSUM; 594 595 DBG(KERN_INFO "%s: checksum %s\n", 596 tun->dev->name, arg ? "disabled" : "enabled"); 597 break; 598 599 case TUNSETPERSIST: 600 /* Disable/Enable persist mode */ 601 if (arg) 602 tun->flags |= TUN_PERSIST; 603 else 604 tun->flags &= ~TUN_PERSIST; 605 606 DBG(KERN_INFO "%s: persist %s\n", 607 tun->dev->name, arg ? "disabled" : "enabled"); 608 break; 609 610 case TUNSETOWNER: 611 /* Set owner of the device */ 612 tun->owner = (uid_t) arg; 613 614 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner); 615 break; 616 617 case TUNSETGROUP: 618 /* Set group of the device */ 619 tun->group= (gid_t) arg; 620 621 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group); 622 break; 623 624 case TUNSETLINK: 625 /* Only allow setting the type when the interface is down */ 626 if (tun->dev->flags & IFF_UP) { 627 DBG(KERN_INFO "%s: Linktype set failed because interface is up\n", 628 tun->dev->name); 629 return -EBUSY; 630 } else { 631 tun->dev->type = (int) arg; 632 DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type); 633 } 634 break; 635 636 #ifdef TUN_DEBUG 637 case TUNSETDEBUG: 638 tun->debug = arg; 639 break; 640 #endif 641 642 case SIOCGIFFLAGS: 643 ifr.ifr_flags = tun->if_flags; 644 if (copy_to_user( argp, &ifr, sizeof ifr)) 645 return -EFAULT; 646 return 0; 647 648 case SIOCSIFFLAGS: 649 /** Set the character device's interface flags. Currently only 650 * IFF_PROMISC and IFF_ALLMULTI are used. */ 651 tun->if_flags = ifr.ifr_flags; 652 DBG(KERN_INFO "%s: interface flags 0x%lx\n", 653 tun->dev->name, tun->if_flags); 654 return 0; 655 656 case SIOCGIFHWADDR: 657 /* Note: the actual net device's address may be different */ 658 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev_addr, 659 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr)); 660 if (copy_to_user( argp, &ifr, sizeof ifr)) 661 return -EFAULT; 662 return 0; 663 664 case SIOCSIFHWADDR: 665 { 666 /* try to set the actual net device's hw address */ 667 int ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr); 668 669 if (ret == 0) { 670 /** Set the character device's hardware address. This is used when 671 * filtering packets being sent from the network device to the character 672 * device. */ 673 memcpy(tun->dev_addr, ifr.ifr_hwaddr.sa_data, 674 min(sizeof ifr.ifr_hwaddr.sa_data, sizeof tun->dev_addr)); 675 DBG(KERN_DEBUG "%s: set hardware address: %x:%x:%x:%x:%x:%x\n", 676 tun->dev->name, 677 tun->dev_addr[0], tun->dev_addr[1], tun->dev_addr[2], 678 tun->dev_addr[3], tun->dev_addr[4], tun->dev_addr[5]); 679 } 680 681 return ret; 682 } 683 684 case SIOCADDMULTI: 685 /** Add the specified group to the character device's multicast filter 686 * list. */ 687 add_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data); 688 DBG(KERN_DEBUG "%s: add multi: %x:%x:%x:%x:%x:%x\n", 689 tun->dev->name, 690 (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1], 691 (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3], 692 (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]); 693 return 0; 694 695 case SIOCDELMULTI: 696 /** Remove the specified group from the character device's multicast 697 * filter list. */ 698 del_multi(tun->chr_filter, ifr.ifr_hwaddr.sa_data); 699 DBG(KERN_DEBUG "%s: del multi: %x:%x:%x:%x:%x:%x\n", 700 tun->dev->name, 701 (u8)ifr.ifr_hwaddr.sa_data[0], (u8)ifr.ifr_hwaddr.sa_data[1], 702 (u8)ifr.ifr_hwaddr.sa_data[2], (u8)ifr.ifr_hwaddr.sa_data[3], 703 (u8)ifr.ifr_hwaddr.sa_data[4], (u8)ifr.ifr_hwaddr.sa_data[5]); 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