net/core/dev_ioctl.c

   1 #include <linux/kmod.h>
   2 #include <linux/netdevice.h>
   3 #include <linux/etherdevice.h>
   4 #include <linux/rtnetlink.h>
   5 #include <linux/net_tstamp.h>
   6 #include <linux/wireless.h>
   7 #include <net/wext.h>
   8
   9 /*
  10  *      Map an interface index to its name (SIOCGIFNAME)
  11  */
  12
  13 /*
  14  *      We need this ioctl for efficient implementation of the
  15  *      if_indextoname() function required by the IPv6 API.  Without
  16  *      it, we would have to search all the interfaces to find a
  17  *      match.  --pb
  18  */
  19
  20 static int dev_ifname(struct net *net, struct ifreq __user *arg)
  21 {
  22         struct ifreq ifr;
  23         int error;
  24
  25         /*
  26          *      Fetch the caller's info block.
  27          */
  28
  29         if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
  30                 return -EFAULT;
  31
  32         error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex);
  33         if (error)
  34                 return error;
  35
  36         if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
  37                 return -EFAULT;
  38         return 0;
  39 }
  40
  41 static gifconf_func_t *gifconf_list[NPROTO];
  42
  43 /**
  44  *      register_gifconf        -       register a SIOCGIF handler
  45  *      @family: Address family
  46  *      @gifconf: Function handler
  47  *
  48  *      Register protocol dependent address dumping routines. The handler
  49  *      that is passed must not be freed or reused until it has been replaced
  50  *      by another handler.
  51  */
  52 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
  53 {
  54         if (family >= NPROTO)
  55                 return -EINVAL;
  56         gifconf_list[family] = gifconf;
  57         return 0;
  58 }
  59 EXPORT_SYMBOL(register_gifconf);
  60
  61 /*
  62  *      Perform a SIOCGIFCONF call. This structure will change
  63  *      size eventually, and there is nothing I can do about it.
  64  *      Thus we will need a 'compatibility mode'.
  65  */
  66
  67 static int dev_ifconf(struct net *net, char __user *arg)
  68 {
  69         struct ifconf ifc;
  70         struct net_device *dev;
  71         char __user *pos;
  72         int len;
  73         int total;
  74         int i;
  75
  76         /*
  77          *      Fetch the caller's info block.
  78          */
  79
  80         if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
  81                 return -EFAULT;
  82
  83         pos = ifc.ifc_buf;
  84         len = ifc.ifc_len;
  85
  86         /*
  87          *      Loop over the interfaces, and write an info block for each.
  88          */
  89
  90         total = 0;
  91         for_each_netdev(net, dev) {
  92                 for (i = 0; i < NPROTO; i++) {
  93                         if (gifconf_list[i]) {
  94                                 int done;
  95                                 if (!pos)
  96                                         done = gifconf_list[i](dev, NULL, 0);
  97                                 else
  98                                         done = gifconf_list[i](dev, pos + total,
  99                                                                len - total);
 100                                 if (done < 0)
 101                                         return -EFAULT;
 102                                 total += done;
 103                         }
 104                 }
 105         }
 106
 107         /*
 108          *      All done.  Write the updated control block back to the caller.
 109          */
 110         ifc.ifc_len = total;
 111
 112         /*
 113          *      Both BSD and Solaris return 0 here, so we do too.
 114          */
 115         return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
 116 }
 117
 118 /*
 119  *      Perform the SIOCxIFxxx calls, inside rcu_read_lock()
 120  */
 121 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
 122 {
 123         int err;
 124         struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
 125
 126         if (!dev)
 127                 return -ENODEV;
 128
 129         switch (cmd) {
 130         case SIOCGIFFLAGS:      /* Get interface flags */
 131                 ifr->ifr_flags = (short) dev_get_flags(dev);
 132                 return 0;
 133
 134         case SIOCGIFMETRIC:     /* Get the metric on the interface
 135                                    (currently unused) */
 136                 ifr->ifr_metric = 0;
 137                 return 0;
 138
 139         case SIOCGIFMTU:        /* Get the MTU of a device */
 140                 ifr->ifr_mtu = dev->mtu;
 141                 return 0;
 142
 143         case SIOCGIFHWADDR:
 144                 if (!dev->addr_len)
 145                         memset(ifr->ifr_hwaddr.sa_data, 0,
 146                                sizeof(ifr->ifr_hwaddr.sa_data));
 147                 else
 148                         memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
 149                                min(sizeof(ifr->ifr_hwaddr.sa_data),
 150                                    (size_t)dev->addr_len));
 151                 ifr->ifr_hwaddr.sa_family = dev->type;
 152                 return 0;
 153
 154         case SIOCGIFSLAVE:
 155                 err = -EINVAL;
 156                 break;
 157
 158         case SIOCGIFMAP:
 159                 ifr->ifr_map.mem_start = dev->mem_start;
 160                 ifr->ifr_map.mem_end   = dev->mem_end;
 161                 ifr->ifr_map.base_addr = dev->base_addr;
 162                 ifr->ifr_map.irq       = dev->irq;
 163                 ifr->ifr_map.dma       = dev->dma;
 164                 ifr->ifr_map.port      = dev->if_port;
 165                 return 0;
 166
 167         case SIOCGIFINDEX:
 168                 ifr->ifr_ifindex = dev->ifindex;
 169                 return 0;
 170
 171         case SIOCGIFTXQLEN:
 172                 ifr->ifr_qlen = dev->tx_queue_len;
 173                 return 0;
 174
 175         default:
 176                 /* dev_ioctl() should ensure this case
 177                  * is never reached
 178                  */
 179                 WARN_ON(1);
 180                 err = -ENOTTY;
 181                 break;
 182
 183         }
 184         return err;
 185 }
 186
 187 static int net_hwtstamp_validate(struct ifreq *ifr)
 188 {
 189         struct hwtstamp_config cfg;
 190         enum hwtstamp_tx_types tx_type;
 191         enum hwtstamp_rx_filters rx_filter;
 192         int tx_type_valid = 0;
 193         int rx_filter_valid = 0;
 194
 195         if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
 196                 return -EFAULT;
 197
 198         if (cfg.flags) /* reserved for future extensions */
 199                 return -EINVAL;
 200
 201         tx_type = cfg.tx_type;
 202         rx_filter = cfg.rx_filter;
 203
 204         switch (tx_type) {
 205         case HWTSTAMP_TX_OFF:
 206         case HWTSTAMP_TX_ON:
 207         case HWTSTAMP_TX_ONESTEP_SYNC:
 208                 tx_type_valid = 1;
 209                 break;
 210         }
 211
 212         switch (rx_filter) {
 213         case HWTSTAMP_FILTER_NONE:
 214         case HWTSTAMP_FILTER_ALL:
 215         case HWTSTAMP_FILTER_SOME:
 216         case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
 217         case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
 218         case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
 219         case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
 220         case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
 221         case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
 222         case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
 223         case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
 224         case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
 225         case HWTSTAMP_FILTER_PTP_V2_EVENT:
 226         case HWTSTAMP_FILTER_PTP_V2_SYNC:
 227         case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
 228                 rx_filter_valid = 1;
 229                 break;
 230         }
 231
 232         if (!tx_type_valid || !rx_filter_valid)
 233                 return -ERANGE;
 234
 235         return 0;
 236 }
 237
 238 /*
 239  *      Perform the SIOCxIFxxx calls, inside rtnl_lock()
 240  */
 241 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
 242 {
 243         int err;
 244         struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
 245         const struct net_device_ops *ops;
 246
 247         if (!dev)
 248                 return -ENODEV;
 249
 250         ops = dev->netdev_ops;
 251
 252         switch (cmd) {
 253         case SIOCSIFFLAGS:      /* Set interface flags */
 254                 return dev_change_flags(dev, ifr->ifr_flags);
 255
 256         case SIOCSIFMETRIC:     /* Set the metric on the interface
 257                                    (currently unused) */
 258                 return -EOPNOTSUPP;
 259
 260         case SIOCSIFMTU:        /* Set the MTU of a device */
 261                 return dev_set_mtu(dev, ifr->ifr_mtu);
 262
 263         case SIOCSIFHWADDR:
 264                 return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
 265
 266         case SIOCSIFHWBROADCAST:
 267                 if (ifr->ifr_hwaddr.sa_family != dev->type)
 268                         return -EINVAL;
 269                 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
 270                        min(sizeof(ifr->ifr_hwaddr.sa_data),
 271                            (size_t)dev->addr_len));
 272                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 273                 return 0;
 274
 275         case SIOCSIFMAP:
 276                 if (ops->ndo_set_config) {
 277                         if (!netif_device_present(dev))
 278                                 return -ENODEV;
 279                         return ops->ndo_set_config(dev, &ifr->ifr_map);
 280                 }
 281                 return -EOPNOTSUPP;
 282
 283         case SIOCADDMULTI:
 284                 if (!ops->ndo_set_rx_mode ||
 285                     ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 286                         return -EINVAL;
 287                 if (!netif_device_present(dev))
 288                         return -ENODEV;
 289                 return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
 290
 291         case SIOCDELMULTI:
 292                 if (!ops->ndo_set_rx_mode ||
 293                     ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 294                         return -EINVAL;
 295                 if (!netif_device_present(dev))
 296                         return -ENODEV;
 297                 return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
 298
 299         case SIOCSIFTXQLEN:
 300                 if (ifr->ifr_qlen < 0)
 301                         return -EINVAL;
 302                 dev->tx_queue_len = ifr->ifr_qlen;
 303                 return 0;
 304
 305         case SIOCSIFNAME:
 306                 ifr->ifr_newname[IFNAMSIZ-1] = '\0';
 307                 return dev_change_name(dev, ifr->ifr_newname);
 308
 309         case SIOCSHWTSTAMP:
 310                 err = net_hwtstamp_validate(ifr);
 311                 if (err)
 312                         return err;
 313                 /* fall through */
 314
 315         /*
 316          *      Unknown or private ioctl
 317          */
 318         default:
 319                 if ((cmd >= SIOCDEVPRIVATE &&
 320                     cmd <= SIOCDEVPRIVATE + 15) ||
 321                     cmd == SIOCBONDENSLAVE ||
 322                     cmd == SIOCBONDRELEASE ||
 323                     cmd == SIOCBONDSETHWADDR ||
 324                     cmd == SIOCBONDSLAVEINFOQUERY ||
 325                     cmd == SIOCBONDINFOQUERY ||
 326                     cmd == SIOCBONDCHANGEACTIVE ||
 327                     cmd == SIOCGMIIPHY ||
 328                     cmd == SIOCGMIIREG ||
 329                     cmd == SIOCSMIIREG ||
 330                     cmd == SIOCBRADDIF ||
 331                     cmd == SIOCBRDELIF ||
 332                     cmd == SIOCSHWTSTAMP ||
 333                     cmd == SIOCGHWTSTAMP ||
 334                     cmd == SIOCWANDEV) {
 335                         err = -EOPNOTSUPP;
 336                         if (ops->ndo_do_ioctl) {
 337                                 if (netif_device_present(dev))
 338                                         err = ops->ndo_do_ioctl(dev, ifr, cmd);
 339                                 else
 340                                         err = -ENODEV;
 341                         }
 342                 } else
 343                         err = -EINVAL;
 344
 345         }
 346         return err;
 347 }
 348
 349 /**
 350  *      dev_load        - load a network module
 351  *      @net: the applicable net namespace
 352  *      @name: name of interface
 353  *
 354  *      If a network interface is not present and the process has suitable
 355  *      privileges this function loads the module. If module loading is not
 356  *      available in this kernel then it becomes a nop.
 357  */
 358
 359 void dev_load(struct net *net, const char *name)
 360 {
 361         struct net_device *dev;
 362         int no_module;
 363
 364         rcu_read_lock();
 365         dev = dev_get_by_name_rcu(net, name);
 366         rcu_read_unlock();
 367
 368         no_module = !dev;
 369         if (no_module && capable(CAP_NET_ADMIN))
 370                 no_module = request_module("netdev-%s", name);
 371         if (no_module && capable(CAP_SYS_MODULE))
 372                 request_module("%s", name);
 373 }
 374 EXPORT_SYMBOL(dev_load);
 375
 376 /*
 377  *      This function handles all "interface"-type I/O control requests. The actual
 378  *      'doing' part of this is dev_ifsioc above.
 379  */
 380
 381 /**
 382  *      dev_ioctl       -       network device ioctl
 383  *      @net: the applicable net namespace
 384  *      @cmd: command to issue
 385  *      @arg: pointer to a struct ifreq in user space
 386  *
 387  *      Issue ioctl functions to devices. This is normally called by the
 388  *      user space syscall interfaces but can sometimes be useful for
 389  *      other purposes. The return value is the return from the syscall if
 390  *      positive or a negative errno code on error.
 391  */
 392
 393 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 394 {
 395         struct ifreq ifr;
 396         int ret;
 397         char *colon;
 398
 399         /* One special case: SIOCGIFCONF takes ifconf argument
 400            and requires shared lock, because it sleeps writing
 401            to user space.
 402          */
 403
 404         if (cmd == SIOCGIFCONF) {
 405                 rtnl_lock();
 406                 ret = dev_ifconf(net, (char __user *) arg);
 407                 rtnl_unlock();
 408                 return ret;
 409         }
 410         if (cmd == SIOCGIFNAME)
 411                 return dev_ifname(net, (struct ifreq __user *)arg);
 412
 413         if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
 414                 return -EFAULT;
 415
 416         ifr.ifr_name[IFNAMSIZ-1] = 0;
 417
 418         colon = strchr(ifr.ifr_name, ':');
 419         if (colon)
 420                 *colon = 0;
 421
 422         /*
 423          *      See which interface the caller is talking about.
 424          */
 425
 426         switch (cmd) {
 427         /*
 428          *      These ioctl calls:
 429          *      - can be done by all.
 430          *      - atomic and do not require locking.
 431          *      - return a value
 432          */
 433         case SIOCGIFFLAGS:
 434         case SIOCGIFMETRIC:
 435         case SIOCGIFMTU:
 436         case SIOCGIFHWADDR:
 437         case SIOCGIFSLAVE:
 438         case SIOCGIFMAP:
 439         case SIOCGIFINDEX:
 440         case SIOCGIFTXQLEN:
 441                 dev_load(net, ifr.ifr_name);
 442                 rcu_read_lock();
 443                 ret = dev_ifsioc_locked(net, &ifr, cmd);
 444                 rcu_read_unlock();
 445                 if (!ret) {
 446                         if (colon)
 447                                 *colon = ':';
 448                         if (copy_to_user(arg, &ifr,
 449                                          sizeof(struct ifreq)))
 450                                 ret = -EFAULT;
 451                 }
 452                 return ret;
 453
 454         case SIOCETHTOOL:
 455                 dev_load(net, ifr.ifr_name);
 456                 rtnl_lock();
 457                 ret = dev_ethtool(net, &ifr);
 458                 rtnl_unlock();
 459                 if (!ret) {
 460                         if (colon)
 461                                 *colon = ':';
 462                         if (copy_to_user(arg, &ifr,
 463                                          sizeof(struct ifreq)))
 464                                 ret = -EFAULT;
 465                 }
 466                 return ret;
 467
 468         /*
 469          *      These ioctl calls:
 470          *      - require superuser power.
 471          *      - require strict serialization.
 472          *      - return a value
 473          */
 474         case SIOCGMIIPHY:
 475         case SIOCGMIIREG:
 476         case SIOCSIFNAME:
 477                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 478                         return -EPERM;
 479                 dev_load(net, ifr.ifr_name);
 480                 rtnl_lock();
 481                 ret = dev_ifsioc(net, &ifr, cmd);
 482                 rtnl_unlock();
 483                 if (!ret) {
 484                         if (colon)
 485                                 *colon = ':';
 486                         if (copy_to_user(arg, &ifr,
 487                                          sizeof(struct ifreq)))
 488                                 ret = -EFAULT;
 489                 }
 490                 return ret;
 491
 492         /*
 493          *      These ioctl calls:
 494          *      - require superuser power.
 495          *      - require strict serialization.
 496          *      - do not return a value
 497          */
 498         case SIOCSIFMAP:
 499         case SIOCSIFTXQLEN:
 500                 if (!capable(CAP_NET_ADMIN))
 501                         return -EPERM;
 502                 /* fall through */
 503         /*
 504          *      These ioctl calls:
 505          *      - require local superuser power.
 506          *      - require strict serialization.
 507          *      - do not return a value
 508          */
 509         case SIOCSIFFLAGS:
 510         case SIOCSIFMETRIC:
 511         case SIOCSIFMTU:
 512         case SIOCSIFHWADDR:
 513         case SIOCSIFSLAVE:
 514         case SIOCADDMULTI:
 515         case SIOCDELMULTI:
 516         case SIOCSIFHWBROADCAST:
 517         case SIOCSMIIREG:
 518         case SIOCBONDENSLAVE:
 519         case SIOCBONDRELEASE:
 520         case SIOCBONDSETHWADDR:
 521         case SIOCBONDCHANGEACTIVE:
 522         case SIOCBRADDIF:
 523         case SIOCBRDELIF:
 524         case SIOCSHWTSTAMP:
 525                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 526                         return -EPERM;
 527                 /* fall through */
 528         case SIOCBONDSLAVEINFOQUERY:
 529         case SIOCBONDINFOQUERY:
 530                 dev_load(net, ifr.ifr_name);
 531                 rtnl_lock();
 532                 ret = dev_ifsioc(net, &ifr, cmd);
 533                 rtnl_unlock();
 534                 return ret;
 535
 536         case SIOCGIFMEM:
 537                 /* Get the per device memory space. We can add this but
 538                  * currently do not support it */
 539         case SIOCSIFMEM:
 540                 /* Set the per device memory buffer space.
 541                  * Not applicable in our case */
 542         case SIOCSIFLINK:
 543                 return -ENOTTY;
 544
 545         /*
 546          *      Unknown or private ioctl.
 547          */
 548         default:
 549                 if (cmd == SIOCWANDEV ||
 550                     cmd == SIOCGHWTSTAMP ||
 551                     (cmd >= SIOCDEVPRIVATE &&
 552                      cmd <= SIOCDEVPRIVATE + 15)) {
 553                         dev_load(net, ifr.ifr_name);
 554                         rtnl_lock();
 555                         ret = dev_ifsioc(net, &ifr, cmd);
 556                         rtnl_unlock();
 557                         if (!ret && copy_to_user(arg, &ifr,
 558                                                  sizeof(struct ifreq)))
 559                                 ret = -EFAULT;
 560                         return ret;
 561                 }
 562                 /* Take care of Wireless Extensions */
 563                 if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
 564                         return wext_handle_ioctl(net, &ifr, cmd, arg);
 565                 return -ENOTTY;
 566         }
 567 }