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   1 /*
   2  *  TUN - Universal TUN/TAP device driver.
   3  *  Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
  16  */
  17
  18 /*
  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
  67 #include <asm/system.h>
  68 #include <asm/uaccess.h>
  69
  70 /* Uncomment to enable debugging */
  71 /* #define TUN_DEBUG 1 */
  72
  73 #ifdef TUN_DEBUG
  74 static int debug;
  75
  76 #define DBG  if(tun->debug)printk
  77 #define DBG1 if(debug==2)printk
  78 #else
  79 #define DBG( a... )
  80 #define DBG1( a... )
  81 #endif
  82
  83 #define FLT_EXACT_COUNT 8
  84 struct tap_filter {
  85         unsigned int    count;    /* Number of addrs. Zero means disabled */
  86         u32             mask[2];  /* Mask of the hashed addrs */
  87         unsigned char   addr[FLT_EXACT_COUNT][ETH_ALEN];
  88 };
  89
  90 struct tun_file {
  91         atomic_t count;
  92         struct tun_struct *tun;
  93         struct net *net;
  94         wait_queue_head_t       read_wait;
  95 };
  96
  97 struct tun_struct {
  98         struct tun_file         *tfile;
  99         unsigned int            flags;
 100         uid_t                   owner;
 101         gid_t                   group;
 102
 103         struct sk_buff_head     readq;
 104
 105         struct net_device       *dev;
 106         struct fasync_struct    *fasync;
 107
 108         struct tap_filter       txflt;
 109
 110 #ifdef TUN_DEBUG
 111         int debug;
 112 #endif
 113 };
 114
 115 static int tun_attach(struct tun_struct *tun, struct file *file)
 116 {
 117         struct tun_file *tfile = file->private_data;
 118         const struct cred *cred = current_cred();
 119         int err;
 120
 121         ASSERT_RTNL();
 122
 123         /* Check permissions */
 124         if (((tun->owner != -1 && cred->euid != tun->owner) ||
 125              (tun->group != -1 && cred->egid != tun->group)) &&
 126                 !capable(CAP_NET_ADMIN))
 127                 return -EPERM;
 128
 129         netif_tx_lock_bh(tun->dev);
 130
 131         err = -EINVAL;
 132         if (tfile->tun)
 133                 goto out;
 134
 135         err = -EBUSY;
 136         if (tun->tfile)
 137                 goto out;
 138
 139         err = 0;
 140         tfile->tun = tun;
 141         tun->tfile = tfile;
 142         dev_hold(tun->dev);
 143         atomic_inc(&tfile->count);
 144
 145 out:
 146         netif_tx_unlock_bh(tun->dev);
 147         return err;
 148 }
 149
 150 static void __tun_detach(struct tun_struct *tun)
 151 {
 152         struct tun_file *tfile = tun->tfile;
 153
 154         /* Detach from net device */
 155         netif_tx_lock_bh(tun->dev);
 156         tfile->tun = NULL;
 157         tun->tfile = NULL;
 158         netif_tx_unlock_bh(tun->dev);
 159
 160         /* Drop read queue */
 161         skb_queue_purge(&tun->readq);
 162
 163         /* Drop the extra count on the net device */
 164         dev_put(tun->dev);
 165 }
 166
 167 static void tun_detach(struct tun_struct *tun)
 168 {
 169         rtnl_lock();
 170         __tun_detach(tun);
 171         rtnl_unlock();
 172 }
 173
 174 static struct tun_struct *__tun_get(struct tun_file *tfile)
 175 {
 176         struct tun_struct *tun = NULL;
 177
 178         if (atomic_inc_not_zero(&tfile->count))
 179                 tun = tfile->tun;
 180
 181         return tun;
 182 }
 183
 184 static struct tun_struct *tun_get(struct file *file)
 185 {
 186         return __tun_get(file->private_data);
 187 }
 188
 189 static void tun_put(struct tun_struct *tun)
 190 {
 191         struct tun_file *tfile = tun->tfile;
 192
 193         if (atomic_dec_and_test(&tfile->count))
 194                 tun_detach(tfile->tun);
 195 }
 196
 197 /* TAP filterting */
 198 static void addr_hash_set(u32 *mask, const u8 *addr)
 199 {
 200         int n = ether_crc(ETH_ALEN, addr) >> 26;
 201         mask[n >> 5] |= (1 << (n & 31));
 202 }
 203
 204 static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
 205 {
 206         int n = ether_crc(ETH_ALEN, addr) >> 26;
 207         return mask[n >> 5] & (1 << (n & 31));
 208 }
 209
 210 static int update_filter(struct tap_filter *filter, void __user *arg)
 211 {
 212         struct { u8 u[ETH_ALEN]; } *addr;
 213         struct tun_filter uf;
 214         int err, alen, n, nexact;
 215
 216         if (copy_from_user(&uf, arg, sizeof(uf)))
 217                 return -EFAULT;
 218
 219         if (!uf.count) {
 220                 /* Disabled */
 221                 filter->count = 0;
 222                 return 0;
 223         }
 224
 225         alen = ETH_ALEN * uf.count;
 226         addr = kmalloc(alen, GFP_KERNEL);
 227         if (!addr)
 228                 return -ENOMEM;
 229
 230         if (copy_from_user(addr, arg + sizeof(uf), alen)) {
 231                 err = -EFAULT;
 232                 goto done;
 233         }
 234
 235         /* The filter is updated without holding any locks. Which is
 236          * perfectly safe. We disable it first and in the worst
 237          * case we'll accept a few undesired packets. */
 238         filter->count = 0;
 239         wmb();
 240
 241         /* Use first set of addresses as an exact filter */
 242         for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
 243                 memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
 244
 245         nexact = n;
 246
 247         /* The rest is hashed */
 248         memset(filter->mask, 0, sizeof(filter->mask));
 249         for (; n < uf.count; n++)
 250                 addr_hash_set(filter->mask, addr[n].u);
 251
 252         /* For ALLMULTI just set the mask to all ones.
 253          * This overrides the mask populated above. */
 254         if ((uf.flags & TUN_FLT_ALLMULTI))
 255                 memset(filter->mask, ~0, sizeof(filter->mask));
 256
 257         /* Now enable the filter */
 258         wmb();
 259         filter->count = nexact;
 260
 261         /* Return the number of exact filters */
 262         err = nexact;
 263
 264 done:
 265         kfree(addr);
 266         return err;
 267 }
 268
 269 /* Returns: 0 - drop, !=0 - accept */
 270 static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
 271 {
 272         /* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
 273          * at this point. */
 274         struct ethhdr *eh = (struct ethhdr *) skb->data;
 275         int i;
 276
 277         /* Exact match */
 278         for (i = 0; i < filter->count; i++)
 279                 if (!compare_ether_addr(eh->h_dest, filter->addr[i]))
 280                         return 1;
 281
 282         /* Inexact match (multicast only) */
 283         if (is_multicast_ether_addr(eh->h_dest))
 284                 return addr_hash_test(filter->mask, eh->h_dest);
 285
 286         return 0;
 287 }
 288
 289 /*
 290  * Checks whether the packet is accepted or not.
 291  * Returns: 0 - drop, !=0 - accept
 292  */
 293 static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
 294 {
 295         if (!filter->count)
 296                 return 1;
 297
 298         return run_filter(filter, skb);
 299 }
 300
 301 /* Network device part of the driver */
 302
 303 static const struct ethtool_ops tun_ethtool_ops;
 304
 305 /* Net device detach from fd. */
 306 static void tun_net_uninit(struct net_device *dev)
 307 {
 308         struct tun_struct *tun = netdev_priv(dev);
 309         struct tun_file *tfile = tun->tfile;
 310
 311         /* Inform the methods they need to stop using the dev.
 312          */
 313         if (tfile) {
 314                 wake_up_all(&tfile->read_wait);
 315                 if (atomic_dec_and_test(&tfile->count))
 316                         __tun_detach(tun);
 317         }
 318 }
 319
 320 /* Net device open. */
 321 static int tun_net_open(struct net_device *dev)
 322 {
 323         netif_start_queue(dev);
 324         return 0;
 325 }
 326
 327 /* Net device close. */
 328 static int tun_net_close(struct net_device *dev)
 329 {
 330         netif_stop_queue(dev);
 331         return 0;
 332 }
 333
 334 /* Net device start xmit */
 335 static int tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
 336 {
 337         struct tun_struct *tun = netdev_priv(dev);
 338
 339         DBG(KERN_INFO "%s: tun_net_xmit %d\n", tun->dev->name, skb->len);
 340
 341         /* Drop packet if interface is not attached */
 342         if (!tun->tfile)
 343                 goto drop;
 344
 345         /* Drop if the filter does not like it.
 346          * This is a noop if the filter is disabled.
 347          * Filter can be enabled only for the TAP devices. */
 348         if (!check_filter(&tun->txflt, skb))
 349                 goto drop;
 350
 351         if (skb_queue_len(&tun->readq) >= dev->tx_queue_len) {
 352                 if (!(tun->flags & TUN_ONE_QUEUE)) {
 353                         /* Normal queueing mode. */
 354                         /* Packet scheduler handles dropping of further packets. */
 355                         netif_stop_queue(dev);
 356
 357                         /* We won't see all dropped packets individually, so overrun
 358                          * error is more appropriate. */
 359                         dev->stats.tx_fifo_errors++;
 360                 } else {
 361                         /* Single queue mode.
 362                          * Driver handles dropping of all packets itself. */
 363                         goto drop;
 364                 }
 365         }
 366
 367         /* Enqueue packet */
 368         skb_queue_tail(&tun->readq, skb);
 369         dev->trans_start = jiffies;
 370
 371         /* Notify and wake up reader process */
 372         if (tun->flags & TUN_FASYNC)
 373                 kill_fasync(&tun->fasync, SIGIO, POLL_IN);
 374         wake_up_interruptible(&tun->tfile->read_wait);
 375         return 0;
 376
 377 drop:
 378         dev->stats.tx_dropped++;
 379         kfree_skb(skb);
 380         return 0;
 381 }
 382
 383 static void tun_net_mclist(struct net_device *dev)
 384 {
 385         /*
 386          * This callback is supposed to deal with mc filter in
 387          * _rx_ path and has nothing to do with the _tx_ path.
 388          * In rx path we always accept everything userspace gives us.
 389          */
 390         return;
 391 }
 392
 393 #define MIN_MTU 68
 394 #define MAX_MTU 65535
 395
 396 static int
 397 tun_net_change_mtu(struct net_device *dev, int new_mtu)
 398 {
 399         if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
 400                 return -EINVAL;
 401         dev->mtu = new_mtu;
 402         return 0;
 403 }
 404
 405 static const struct net_device_ops tun_netdev_ops = {
 406         .ndo_uninit             = tun_net_uninit,
 407         .ndo_open               = tun_net_open,
 408         .ndo_stop               = tun_net_close,
 409         .ndo_start_xmit         = tun_net_xmit,
 410         .ndo_change_mtu         = tun_net_change_mtu,
 411 };
 412
 413 static const struct net_device_ops tap_netdev_ops = {
 414         .ndo_uninit             = tun_net_uninit,
 415         .ndo_open               = tun_net_open,
 416         .ndo_stop               = tun_net_close,
 417         .ndo_start_xmit         = tun_net_xmit,
 418         .ndo_change_mtu         = tun_net_change_mtu,
 419         .ndo_set_multicast_list = tun_net_mclist,
 420         .ndo_set_mac_address    = eth_mac_addr,
 421         .ndo_validate_addr      = eth_validate_addr,
 422 };
 423
 424 /* Initialize net device. */
 425 static void tun_net_init(struct net_device *dev)
 426 {
 427         struct tun_struct *tun = netdev_priv(dev);
 428
 429         switch (tun->flags & TUN_TYPE_MASK) {
 430         case TUN_TUN_DEV:
 431                 dev->netdev_ops = &tun_netdev_ops;
 432
 433                 /* Point-to-Point TUN Device */
 434                 dev->hard_header_len = 0;
 435                 dev->addr_len = 0;
 436                 dev->mtu = 1500;
 437
 438                 /* Zero header length */
 439                 dev->type = ARPHRD_NONE;
 440                 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 441                 dev->tx_queue_len = TUN_READQ_SIZE;  /* We prefer our own queue length */
 442                 break;
 443
 444         case TUN_TAP_DEV:
 445                 dev->netdev_ops = &tap_netdev_ops;
 446                 /* Ethernet TAP Device */
 447                 ether_setup(dev);
 448
 449                 random_ether_addr(dev->dev_addr);
 450
 451                 dev->tx_queue_len = TUN_READQ_SIZE;  /* We prefer our own queue length */
 452                 break;
 453         }
 454 }
 455
 456 /* Character device part */
 457
 458 /* Poll */
 459 static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
 460 {
 461         struct tun_file *tfile = file->private_data;
 462         struct tun_struct *tun = __tun_get(tfile);
 463         unsigned int mask = POLLOUT | POLLWRNORM;
 464
 465         if (!tun)
 466                 return POLLERR;
 467
 468         DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
 469
 470         poll_wait(file, &tfile->read_wait, wait);
 471
 472         if (!skb_queue_empty(&tun->readq))
 473                 mask |= POLLIN | POLLRDNORM;
 474
 475         if (tun->dev->reg_state != NETREG_REGISTERED)
 476                 mask = POLLERR;
 477
 478         tun_put(tun);
 479         return mask;
 480 }
 481
 482 /* prepad is the amount to reserve at front.  len is length after that.
 483  * linear is a hint as to how much to copy (usually headers). */
 484 static struct sk_buff *tun_alloc_skb(size_t prepad, size_t len, size_t linear,
 485                                      gfp_t gfp)
 486 {
 487         struct sk_buff *skb;
 488         unsigned int i;
 489
 490         skb = alloc_skb(prepad + len, gfp|__GFP_NOWARN);
 491         if (skb) {
 492                 skb_reserve(skb, prepad);
 493                 skb_put(skb, len);
 494                 return skb;
 495         }
 496
 497         /* Under a page?  Don't bother with paged skb. */
 498         if (prepad + len < PAGE_SIZE)
 499                 return NULL;
 500
 501         /* Start with a normal skb, and add pages. */
 502         skb = alloc_skb(prepad + linear, gfp);
 503         if (!skb)
 504                 return NULL;
 505
 506         skb_reserve(skb, prepad);
 507         skb_put(skb, linear);
 508
 509         len -= linear;
 510
 511         for (i = 0; i < MAX_SKB_FRAGS; i++) {
 512                 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
 513
 514                 f->page = alloc_page(gfp|__GFP_ZERO);
 515                 if (!f->page)
 516                         break;
 517
 518                 f->page_offset = 0;
 519                 f->size = PAGE_SIZE;
 520
 521                 skb->data_len += PAGE_SIZE;
 522                 skb->len += PAGE_SIZE;
 523                 skb->truesize += PAGE_SIZE;
 524                 skb_shinfo(skb)->nr_frags++;
 525
 526                 if (len < PAGE_SIZE) {
 527                         len = 0;
 528                         break;
 529                 }
 530                 len -= PAGE_SIZE;
 531         }
 532
 533         /* Too large, or alloc fail? */
 534         if (unlikely(len)) {
 535                 kfree_skb(skb);
 536                 skb = NULL;
 537         }
 538
 539         return skb;
 540 }
 541
 542 /* Get packet from user space buffer */
 543 static __inline__ ssize_t tun_get_user(struct tun_struct *tun, struct iovec *iv, size_t count)
 544 {
 545         struct tun_pi pi = { 0, __constant_htons(ETH_P_IP) };
 546         struct sk_buff *skb;
 547         size_t len = count, align = 0;
 548         struct virtio_net_hdr gso = { 0 };
 549
 550         if (!(tun->flags & TUN_NO_PI)) {
 551                 if ((len -= sizeof(pi)) > count)
 552                         return -EINVAL;
 553
 554                 if(memcpy_fromiovec((void *)&pi, iv, sizeof(pi)))
 555                         return -EFAULT;
 556         }
 557
 558         if (tun->flags & TUN_VNET_HDR) {
 559                 if ((len -= sizeof(gso)) > count)
 560                         return -EINVAL;
 561
 562                 if (memcpy_fromiovec((void *)&gso, iv, sizeof(gso)))
 563                         return -EFAULT;
 564
 565                 if (gso.hdr_len > len)
 566                         return -EINVAL;
 567         }
 568
 569         if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) {
 570                 align = NET_IP_ALIGN;
 571                 if (unlikely(len < ETH_HLEN))
 572                         return -EINVAL;
 573         }
 574
 575         if (!(skb = tun_alloc_skb(align, len, gso.hdr_len, GFP_KERNEL))) {
 576                 tun->dev->stats.rx_dropped++;
 577                 return -ENOMEM;
 578         }
 579
 580         if (skb_copy_datagram_from_iovec(skb, 0, iv, len)) {
 581                 tun->dev->stats.rx_dropped++;
 582                 kfree_skb(skb);
 583                 return -EFAULT;
 584         }
 585
 586         if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
 587                 if (!skb_partial_csum_set(skb, gso.csum_start,
 588                                           gso.csum_offset)) {
 589                         tun->dev->stats.rx_frame_errors++;
 590                         kfree_skb(skb);
 591                         return -EINVAL;
 592                 }
 593         } else if (tun->flags & TUN_NOCHECKSUM)
 594                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 595
 596         switch (tun->flags & TUN_TYPE_MASK) {
 597         case TUN_TUN_DEV:
 598                 if (tun->flags & TUN_NO_PI) {
 599                         switch (skb->data[0] & 0xf0) {
 600                         case 0x40:
 601                                 pi.proto = htons(ETH_P_IP);
 602                                 break;
 603                         case 0x60:
 604                                 pi.proto = htons(ETH_P_IPV6);
 605                                 break;
 606                         default:
 607                                 tun->dev->stats.rx_dropped++;
 608                                 kfree_skb(skb);
 609                                 return -EINVAL;
 610                         }
 611                 }
 612
 613                 skb_reset_mac_header(skb);
 614                 skb->protocol = pi.proto;
 615                 skb->dev = tun->dev;
 616                 break;
 617         case TUN_TAP_DEV:
 618                 skb->protocol = eth_type_trans(skb, tun->dev);
 619                 break;
 620         };
 621
 622         if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
 623                 pr_debug("GSO!\n");
 624                 switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
 625                 case VIRTIO_NET_HDR_GSO_TCPV4:
 626                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
 627                         break;
 628                 case VIRTIO_NET_HDR_GSO_TCPV6:
 629                         skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
 630                         break;
 631                 default:
 632                         tun->dev->stats.rx_frame_errors++;
 633                         kfree_skb(skb);
 634                         return -EINVAL;
 635                 }
 636
 637                 if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN)
 638                         skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
 639
 640                 skb_shinfo(skb)->gso_size = gso.gso_size;
 641                 if (skb_shinfo(skb)->gso_size == 0) {
 642                         tun->dev->stats.rx_frame_errors++;
 643                         kfree_skb(skb);
 644                         return -EINVAL;
 645                 }
 646
 647                 /* Header must be checked, and gso_segs computed. */
 648                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
 649                 skb_shinfo(skb)->gso_segs = 0;
 650         }
 651
 652         netif_rx_ni(skb);
 653
 654         tun->dev->stats.rx_packets++;
 655         tun->dev->stats.rx_bytes += len;
 656
 657         return count;
 658 }
 659
 660 static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv,
 661                               unsigned long count, loff_t pos)
 662 {
 663         struct tun_struct *tun = tun_get(iocb->ki_filp);
 664         ssize_t result;
 665
 666         if (!tun)
 667                 return -EBADFD;
 668
 669         DBG(KERN_INFO "%s: tun_chr_write %ld\n", tun->dev->name, count);
 670
 671         result = tun_get_user(tun, (struct iovec *) iv, iov_length(iv, count));
 672
 673         tun_put(tun);
 674         return result;
 675 }
 676
 677 /* Put packet to the user space buffer */
 678 static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
 679                                        struct sk_buff *skb,
 680                                        struct iovec *iv, int len)
 681 {
 682         struct tun_pi pi = { 0, skb->protocol };
 683         ssize_t total = 0;
 684
 685         if (!(tun->flags & TUN_NO_PI)) {
 686                 if ((len -= sizeof(pi)) < 0)
 687                         return -EINVAL;
 688
 689                 if (len < skb->len) {
 690                         /* Packet will be striped */
 691                         pi.flags |= TUN_PKT_STRIP;
 692                 }
 693
 694                 if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
 695                         return -EFAULT;
 696                 total += sizeof(pi);
 697         }
 698
 699         if (tun->flags & TUN_VNET_HDR) {
 700                 struct virtio_net_hdr gso = { 0 }; /* no info leak */
 701                 if ((len -= sizeof(gso)) < 0)
 702                         return -EINVAL;
 703
 704                 if (skb_is_gso(skb)) {
 705                         struct skb_shared_info *sinfo = skb_shinfo(skb);
 706
 707                         /* This is a hint as to how much should be linear. */
 708                         gso.hdr_len = skb_headlen(skb);
 709                         gso.gso_size = sinfo->gso_size;
 710                         if (sinfo->gso_type & SKB_GSO_TCPV4)
 711                                 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
 712                         else if (sinfo->gso_type & SKB_GSO_TCPV6)
 713                                 gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
 714                         else
 715                                 BUG();
 716                         if (sinfo->gso_type & SKB_GSO_TCP_ECN)
 717                                 gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
 718                 } else
 719                         gso.gso_type = VIRTIO_NET_HDR_GSO_NONE;
 720
 721                 if (skb->ip_summed == CHECKSUM_PARTIAL) {
 722                         gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
 723                         gso.csum_start = skb->csum_start - skb_headroom(skb);
 724                         gso.csum_offset = skb->csum_offset;
 725                 } /* else everything is zero */
 726
 727                 if (unlikely(memcpy_toiovec(iv, (void *)&gso, sizeof(gso))))
 728                         return -EFAULT;
 729                 total += sizeof(gso);
 730         }
 731
 732         len = min_t(int, skb->len, len);
 733
 734         skb_copy_datagram_iovec(skb, 0, iv, len);
 735         total += len;
 736
 737         tun->dev->stats.tx_packets++;
 738         tun->dev->stats.tx_bytes += len;
 739
 740         return total;
 741 }
 742
 743 static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv,
 744                             unsigned long count, loff_t pos)
 745 {
 746         struct file *file = iocb->ki_filp;
 747         struct tun_file *tfile = file->private_data;
 748         struct tun_struct *tun = __tun_get(tfile);
 749         DECLARE_WAITQUEUE(wait, current);
 750         struct sk_buff *skb;
 751         ssize_t len, ret = 0;
 752
 753         if (!tun)
 754                 return -EBADFD;
 755
 756         DBG(KERN_INFO "%s: tun_chr_read\n", tun->dev->name);
 757
 758         len = iov_length(iv, count);
 759         if (len < 0) {
 760                 ret = -EINVAL;
 761                 goto out;
 762         }
 763
 764         add_wait_queue(&tfile->read_wait, &wait);
 765         while (len) {
 766                 current->state = TASK_INTERRUPTIBLE;
 767
 768                 /* Read frames from the queue */
 769                 if (!(skb=skb_dequeue(&tun->readq))) {
 770                         if (file->f_flags & O_NONBLOCK) {
 771                                 ret = -EAGAIN;
 772                                 break;
 773                         }
 774                         if (signal_pending(current)) {
 775                                 ret = -ERESTARTSYS;
 776                                 break;
 777                         }
 778                         if (tun->dev->reg_state != NETREG_REGISTERED) {
 779                                 ret = -EIO;
 780                                 break;
 781                         }
 782
 783                         /* Nothing to read, let's sleep */
 784                         schedule();
 785                         continue;
 786                 }
 787                 netif_wake_queue(tun->dev);
 788
 789                 ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
 790                 kfree_skb(skb);
 791                 break;
 792         }
 793
 794         current->state = TASK_RUNNING;
 795         remove_wait_queue(&tfile->read_wait, &wait);
 796
 797 out:
 798         tun_put(tun);
 799         return ret;
 800 }
 801
 802 static void tun_setup(struct net_device *dev)
 803 {
 804         struct tun_struct *tun = netdev_priv(dev);
 805
 806         skb_queue_head_init(&tun->readq);
 807
 808         tun->owner = -1;
 809         tun->group = -1;
 810
 811         dev->ethtool_ops = &tun_ethtool_ops;
 812         dev->destructor = free_netdev;
 813 }
 814
 815 static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
 816 {
 817         struct tun_struct *tun;
 818         struct net_device *dev;
 819         int err;
 820
 821         dev = __dev_get_by_name(net, ifr->ifr_name);
 822         if (dev) {
 823                 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
 824                         tun = netdev_priv(dev);
 825                 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
 826                         tun = netdev_priv(dev);
 827                 else
 828                         return -EINVAL;
 829
 830                 err = tun_attach(tun, file);
 831                 if (err < 0)
 832                         return err;
 833         }
 834         else {
 835                 char *name;
 836                 unsigned long flags = 0;
 837
 838                 err = -EINVAL;
 839
 840                 if (!capable(CAP_NET_ADMIN))
 841                         return -EPERM;
 842
 843                 /* Set dev type */
 844                 if (ifr->ifr_flags & IFF_TUN) {
 845                         /* TUN device */
 846                         flags |= TUN_TUN_DEV;
 847                         name = "tun%d";
 848                 } else if (ifr->ifr_flags & IFF_TAP) {
 849                         /* TAP device */
 850                         flags |= TUN_TAP_DEV;
 851                         name = "tap%d";
 852                 } else
 853                         goto failed;
 854
 855                 if (*ifr->ifr_name)
 856                         name = ifr->ifr_name;
 857
 858                 dev = alloc_netdev(sizeof(struct tun_struct), name,
 859                                    tun_setup);
 860                 if (!dev)
 861                         return -ENOMEM;
 862
 863                 dev_net_set(dev, net);
 864
 865                 tun = netdev_priv(dev);
 866                 tun->dev = dev;
 867                 tun->flags = flags;
 868                 tun->txflt.count = 0;
 869
 870                 tun_net_init(dev);
 871
 872                 if (strchr(dev->name, '%')) {
 873                         err = dev_alloc_name(dev, dev->name);
 874                         if (err < 0)
 875                                 goto err_free_dev;
 876                 }
 877
 878                 err = register_netdevice(tun->dev);
 879                 if (err < 0)
 880                         goto err_free_dev;
 881
 882                 err = tun_attach(tun, file);
 883                 if (err < 0)
 884                         goto err_free_dev;
 885         }
 886
 887         DBG(KERN_INFO "%s: tun_set_iff\n", tun->dev->name);
 888
 889         if (ifr->ifr_flags & IFF_NO_PI)
 890                 tun->flags |= TUN_NO_PI;
 891         else
 892                 tun->flags &= ~TUN_NO_PI;
 893
 894         if (ifr->ifr_flags & IFF_ONE_QUEUE)
 895                 tun->flags |= TUN_ONE_QUEUE;
 896         else
 897                 tun->flags &= ~TUN_ONE_QUEUE;
 898
 899         if (ifr->ifr_flags & IFF_VNET_HDR)
 900                 tun->flags |= TUN_VNET_HDR;
 901         else
 902                 tun->flags &= ~TUN_VNET_HDR;
 903
 904         /* Make sure persistent devices do not get stuck in
 905          * xoff state.
 906          */
 907         if (netif_running(tun->dev))
 908                 netif_wake_queue(tun->dev);
 909
 910         strcpy(ifr->ifr_name, tun->dev->name);
 911         return 0;
 912
 913  err_free_dev:
 914         free_netdev(dev);
 915  failed:
 916         return err;
 917 }
 918
 919 static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr)
 920 {
 921         struct tun_struct *tun = tun_get(file);
 922
 923         if (!tun)
 924                 return -EBADFD;
 925
 926         DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
 927
 928         strcpy(ifr->ifr_name, tun->dev->name);
 929
 930         ifr->ifr_flags = 0;
 931
 932         if (ifr->ifr_flags & TUN_TUN_DEV)
 933                 ifr->ifr_flags |= IFF_TUN;
 934         else
 935                 ifr->ifr_flags |= IFF_TAP;
 936
 937         if (tun->flags & TUN_NO_PI)
 938                 ifr->ifr_flags |= IFF_NO_PI;
 939
 940         if (tun->flags & TUN_ONE_QUEUE)
 941                 ifr->ifr_flags |= IFF_ONE_QUEUE;
 942
 943         if (tun->flags & TUN_VNET_HDR)
 944                 ifr->ifr_flags |= IFF_VNET_HDR;
 945
 946         tun_put(tun);
 947         return 0;
 948 }
 949
 950 /* This is like a cut-down ethtool ops, except done via tun fd so no
 951  * privs required. */
 952 static int set_offload(struct net_device *dev, unsigned long arg)
 953 {
 954         unsigned int old_features, features;
 955
 956         old_features = dev->features;
 957         /* Unset features, set them as we chew on the arg. */
 958         features = (old_features & ~(NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST
 959                                     |NETIF_F_TSO_ECN|NETIF_F_TSO|NETIF_F_TSO6));
 960
 961         if (arg & TUN_F_CSUM) {
 962                 features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
 963                 arg &= ~TUN_F_CSUM;
 964
 965                 if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
 966                         if (arg & TUN_F_TSO_ECN) {
 967                                 features |= NETIF_F_TSO_ECN;
 968                                 arg &= ~TUN_F_TSO_ECN;
 969                         }
 970                         if (arg & TUN_F_TSO4)
 971                                 features |= NETIF_F_TSO;
 972                         if (arg & TUN_F_TSO6)
 973                                 features |= NETIF_F_TSO6;
 974                         arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
 975                 }
 976         }
 977
 978         /* This gives the user a way to test for new features in future by
 979          * trying to set them. */
 980         if (arg)
 981                 return -EINVAL;
 982
 983         dev->features = features;
 984         if (old_features != dev->features)
 985                 netdev_features_change(dev);
 986
 987         return 0;
 988 }
 989
 990 static int tun_chr_ioctl(struct inode *inode, struct file *file,
 991                          unsigned int cmd, unsigned long arg)
 992 {
 993         struct tun_file *tfile = file->private_data;
 994         struct tun_struct *tun;
 995         void __user* argp = (void __user*)arg;
 996         struct ifreq ifr;
 997         int ret;
 998
 999         if (cmd == TUNSETIFF || _IOC_TYPE(cmd) == 0x89)
1000                 if (copy_from_user(&ifr, argp, sizeof ifr))
1001                         return -EFAULT;
1002
1003         if (cmd == TUNGETFEATURES) {
1004                 /* Currently this just means: "what IFF flags are valid?".
1005                  * This is needed because we never checked for invalid flags on
1006                  * TUNSETIFF. */
1007                 return put_user(IFF_TUN | IFF_TAP | IFF_NO_PI | IFF_ONE_QUEUE |
1008                                 IFF_VNET_HDR,
1009                                 (unsigned int __user*)argp);
1010         }
1011
1012         tun = __tun_get(tfile);
1013         if (cmd == TUNSETIFF && !tun) {
1014                 int err;
1015
1016                 ifr.ifr_name[IFNAMSIZ-1] = '\0';
1017
1018                 rtnl_lock();
1019                 err = tun_set_iff(tfile->net, file, &ifr);
1020                 rtnl_unlock();
1021
1022                 if (err)
1023                         return err;
1024
1025                 if (copy_to_user(argp, &ifr, sizeof(ifr)))
1026                         return -EFAULT;
1027                 return 0;
1028         }
1029
1030
1031         if (!tun)
1032                 return -EBADFD;
1033
1034         DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
1035
1036         ret = 0;
1037         switch (cmd) {
1038         case TUNGETIFF:
1039                 ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr);
1040                 if (ret)
1041                         break;
1042
1043                 if (copy_to_user(argp, &ifr, sizeof(ifr)))
1044                         ret = -EFAULT;
1045                 break;
1046
1047         case TUNSETNOCSUM:
1048                 /* Disable/Enable checksum */
1049                 if (arg)
1050                         tun->flags |= TUN_NOCHECKSUM;
1051                 else
1052                         tun->flags &= ~TUN_NOCHECKSUM;
1053
1054                 DBG(KERN_INFO "%s: checksum %s\n",
1055                     tun->dev->name, arg ? "disabled" : "enabled");
1056                 break;
1057
1058         case TUNSETPERSIST:
1059                 /* Disable/Enable persist mode */
1060                 if (arg)
1061                         tun->flags |= TUN_PERSIST;
1062                 else
1063                         tun->flags &= ~TUN_PERSIST;
1064
1065                 DBG(KERN_INFO "%s: persist %s\n",
1066                     tun->dev->name, arg ? "enabled" : "disabled");
1067                 break;
1068
1069         case TUNSETOWNER:
1070                 /* Set owner of the device */
1071                 tun->owner = (uid_t) arg;
1072
1073                 DBG(KERN_INFO "%s: owner set to %d\n", tun->dev->name, tun->owner);
1074                 break;
1075
1076         case TUNSETGROUP:
1077                 /* Set group of the device */
1078                 tun->group= (gid_t) arg;
1079
1080                 DBG(KERN_INFO "%s: group set to %d\n", tun->dev->name, tun->group);
1081                 break;
1082
1083         case TUNSETLINK:
1084                 /* Only allow setting the type when the interface is down */
1085                 rtnl_lock();
1086                 if (tun->dev->flags & IFF_UP) {
1087                         DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
1088                                 tun->dev->name);
1089                         ret = -EBUSY;
1090                 } else {
1091                         tun->dev->type = (int) arg;
1092                         DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
1093                         ret = 0;
1094                 }
1095                 rtnl_unlock();
1096                 break;
1097
1098 #ifdef TUN_DEBUG
1099         case TUNSETDEBUG:
1100                 tun->debug = arg;
1101                 break;
1102 #endif
1103         case TUNSETOFFLOAD:
1104                 rtnl_lock();
1105                 ret = set_offload(tun->dev, arg);
1106                 rtnl_unlock();
1107                 break;
1108
1109         case TUNSETTXFILTER:
1110                 /* Can be set only for TAPs */
1111                 ret = -EINVAL;
1112                 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
1113                         break;
1114                 rtnl_lock();
1115                 ret = update_filter(&tun->txflt, (void __user *)arg);
1116                 rtnl_unlock();
1117                 break;
1118
1119         case SIOCGIFHWADDR:
1120                 /* Get hw addres */
1121                 memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
1122                 ifr.ifr_hwaddr.sa_family = tun->dev->type;
1123                 if (copy_to_user(argp, &ifr, sizeof ifr))
1124                         ret = -EFAULT;
1125                 break;
1126
1127         case SIOCSIFHWADDR:
1128                 /* Set hw address */
1129                 DBG(KERN_DEBUG "%s: set hw address: %pM\n",
1130                         tun->dev->name, ifr.ifr_hwaddr.sa_data);
1131
1132                 rtnl_lock();
1133                 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
1134                 rtnl_unlock();
1135                 break;
1136         default:
1137                 ret = -EINVAL;
1138                 break;
1139         };
1140
1141         tun_put(tun);
1142         return ret;
1143 }
1144
1145 static int tun_chr_fasync(int fd, struct file *file, int on)
1146 {
1147         struct tun_struct *tun = tun_get(file);
1148         int ret;
1149
1150         if (!tun)
1151                 return -EBADFD;
1152
1153         DBG(KERN_INFO "%s: tun_chr_fasync %d\n", tun->dev->name, on);
1154
1155         lock_kernel();
1156         if ((ret = fasync_helper(fd, file, on, &tun->fasync)) < 0)
1157                 goto out;
1158
1159         if (on) {
1160                 ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0);
1161                 if (ret)
1162                         goto out;
1163                 tun->flags |= TUN_FASYNC;
1164         } else
1165                 tun->flags &= ~TUN_FASYNC;
1166         ret = 0;
1167 out:
1168         unlock_kernel();
1169         tun_put(tun);
1170         return ret;
1171 }
1172
1173 static int tun_chr_open(struct inode *inode, struct file * file)
1174 {
1175         struct tun_file *tfile;
1176         cycle_kernel_lock();
1177         DBG1(KERN_INFO "tunX: tun_chr_open\n");
1178
1179         tfile = kmalloc(sizeof(*tfile), GFP_KERNEL);
1180         if (!tfile)
1181                 return -ENOMEM;
1182         atomic_set(&tfile->count, 0);
1183         tfile->tun = NULL;
1184         tfile->net = get_net(current->nsproxy->net_ns);
1185         init_waitqueue_head(&tfile->read_wait);
1186         file->private_data = tfile;
1187         return 0;
1188 }
1189
1190 static int tun_chr_close(struct inode *inode, struct file *file)
1191 {
1192         struct tun_file *tfile = file->private_data;
1193         struct tun_struct *tun = __tun_get(tfile);
1194
1195
1196         if (tun) {
1197                 DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
1198
1199                 rtnl_lock();
1200                 __tun_detach(tun);
1201
1202                 /* If desireable, unregister the netdevice. */
1203                 if (!(tun->flags & TUN_PERSIST))
1204                         unregister_netdevice(tun->dev);
1205
1206                 rtnl_unlock();
1207         }
1208
1209         put_net(tfile->net);
1210         kfree(tfile);
1211
1212         return 0;
1213 }
1214
1215 static const struct file_operations tun_fops = {
1216         .owner  = THIS_MODULE,
1217         .llseek = no_llseek,
1218         .read  = do_sync_read,
1219         .aio_read  = tun_chr_aio_read,
1220         .write = do_sync_write,
1221         .aio_write = tun_chr_aio_write,
1222         .poll   = tun_chr_poll,
1223         .ioctl  = tun_chr_ioctl,
1224         .open   = tun_chr_open,
1225         .release = tun_chr_close,
1226         .fasync = tun_chr_fasync
1227 };
1228
1229 static struct miscdevice tun_miscdev = {
1230         .minor = TUN_MINOR,
1231         .name = "tun",
1232         .fops = &tun_fops,
1233 };
1234
1235 /* ethtool interface */
1236
1237 static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1238 {
1239         cmd->supported          = 0;
1240         cmd->advertising        = 0;
1241         cmd->speed              = SPEED_10;
1242         cmd->duplex             = DUPLEX_FULL;
1243         cmd->port               = PORT_TP;
1244         cmd->phy_address        = 0;
1245         cmd->transceiver        = XCVR_INTERNAL;
1246         cmd->autoneg            = AUTONEG_DISABLE;
1247         cmd->maxtxpkt           = 0;
1248         cmd->maxrxpkt           = 0;
1249         return 0;
1250 }
1251
1252 static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1253 {
1254         struct tun_struct *tun = netdev_priv(dev);
1255
1256         strcpy(info->driver, DRV_NAME);
1257         strcpy(info->version, DRV_VERSION);
1258         strcpy(info->fw_version, "N/A");
1259
1260         switch (tun->flags & TUN_TYPE_MASK) {
1261         case TUN_TUN_DEV:
1262                 strcpy(info->bus_info, "tun");
1263                 break;
1264         case TUN_TAP_DEV:
1265                 strcpy(info->bus_info, "tap");
1266                 break;
1267         }
1268 }
1269
1270 static u32 tun_get_msglevel(struct net_device *dev)
1271 {
1272 #ifdef TUN_DEBUG
1273         struct tun_struct *tun = netdev_priv(dev);
1274         return tun->debug;
1275 #else
1276         return -EOPNOTSUPP;
1277 #endif
1278 }
1279
1280 static void tun_set_msglevel(struct net_device *dev, u32 value)
1281 {
1282 #ifdef TUN_DEBUG
1283         struct tun_struct *tun = netdev_priv(dev);
1284         tun->debug = value;
1285 #endif
1286 }
1287
1288 static u32 tun_get_link(struct net_device *dev)
1289 {
1290         struct tun_struct *tun = netdev_priv(dev);
1291         return !!tun->tfile;
1292 }
1293
1294 static u32 tun_get_rx_csum(struct net_device *dev)
1295 {
1296         struct tun_struct *tun = netdev_priv(dev);
1297         return (tun->flags & TUN_NOCHECKSUM) == 0;
1298 }
1299
1300 static int tun_set_rx_csum(struct net_device *dev, u32 data)
1301 {
1302         struct tun_struct *tun = netdev_priv(dev);
1303         if (data)
1304                 tun->flags &= ~TUN_NOCHECKSUM;
1305         else
1306                 tun->flags |= TUN_NOCHECKSUM;
1307         return 0;
1308 }
1309
1310 static const struct ethtool_ops tun_ethtool_ops = {
1311         .get_settings   = tun_get_settings,
1312         .get_drvinfo    = tun_get_drvinfo,
1313         .get_msglevel   = tun_get_msglevel,
1314         .set_msglevel   = tun_set_msglevel,
1315         .get_link       = tun_get_link,
1316         .get_rx_csum    = tun_get_rx_csum,
1317         .set_rx_csum    = tun_set_rx_csum
1318 };
1319
1320 static int tun_init_net(struct net *net)
1321 {
1322         return 0;
1323 }
1324
1325 static void tun_exit_net(struct net *net)
1326 {
1327         struct net_device *dev, *next;
1328
1329         rtnl_lock();
1330         for_each_netdev_safe(net, dev, next) {
1331                 if (dev->ethtool_ops != &tun_ethtool_ops)
1332                         continue;
1333                 DBG(KERN_INFO "%s cleaned up\n", dev->name);
1334                 unregister_netdevice(dev);
1335         }
1336         rtnl_unlock();
1337 }
1338
1339 static struct pernet_operations tun_net_ops = {
1340         .init = tun_init_net,
1341         .exit = tun_exit_net,
1342 };
1343
1344 static int __init tun_init(void)
1345 {
1346         int ret = 0;
1347
1348         printk(KERN_INFO "tun: %s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
1349         printk(KERN_INFO "tun: %s\n", DRV_COPYRIGHT);
1350
1351         ret = register_pernet_device(&tun_net_ops);
1352         if (ret) {
1353                 printk(KERN_ERR "tun: Can't register pernet ops\n");
1354                 goto err_pernet;
1355         }
1356
1357         ret = misc_register(&tun_miscdev);
1358         if (ret) {
1359                 printk(KERN_ERR "tun: Can't register misc device %d\n", TUN_MINOR);
1360                 goto err_misc;
1361         }
1362         return 0;
1363
1364 err_misc:
1365         unregister_pernet_device(&tun_net_ops);
1366 err_pernet:
1367         return ret;
1368 }
1369
1370 static void tun_cleanup(void)
1371 {
1372         misc_deregister(&tun_miscdev);
1373         unregister_pernet_device(&tun_net_ops);
1374 }
1375
1376 module_init(tun_init);
1377 module_exit(tun_cleanup);
1378 MODULE_DESCRIPTION(DRV_DESCRIPTION);
1379 MODULE_AUTHOR(DRV_COPYRIGHT);
1380 MODULE_LICENSE("GPL");
1381 MODULE_ALIAS_MISCDEV(TUN_MINOR);