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         case HWTSTAMP_FILTER_NTP_ALL:
 229                 rx_filter_valid = 1;
 230                 break;
 231         }
 232
 233         if (!tx_type_valid || !rx_filter_valid)
 234                 return -ERANGE;
 235
 236         return 0;
 237 }
 238
 239 /*
 240  *      Perform the SIOCxIFxxx calls, inside rtnl_lock()
 241  */
 242 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
 243 {
 244         int err;
 245         struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
 246         const struct net_device_ops *ops;
 247
 248         if (!dev)
 249                 return -ENODEV;
 250
 251         ops = dev->netdev_ops;
 252
 253         switch (cmd) {
 254         case SIOCSIFFLAGS:      /* Set interface flags */
 255                 return dev_change_flags(dev, ifr->ifr_flags);
 256
 257         case SIOCSIFMETRIC:     /* Set the metric on the interface
 258                                    (currently unused) */
 259                 return -EOPNOTSUPP;
 260
 261         case SIOCSIFMTU:        /* Set the MTU of a device */
 262                 return dev_set_mtu(dev, ifr->ifr_mtu);
 263
 264         case SIOCSIFHWADDR:
 265                 return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
 266
 267         case SIOCSIFHWBROADCAST:
 268                 if (ifr->ifr_hwaddr.sa_family != dev->type)
 269                         return -EINVAL;
 270                 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
 271                        min(sizeof(ifr->ifr_hwaddr.sa_data),
 272                            (size_t)dev->addr_len));
 273                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 274                 return 0;
 275
 276         case SIOCSIFMAP:
 277                 if (ops->ndo_set_config) {
 278                         if (!netif_device_present(dev))
 279                                 return -ENODEV;
 280                         return ops->ndo_set_config(dev, &ifr->ifr_map);
 281                 }
 282                 return -EOPNOTSUPP;
 283
 284         case SIOCADDMULTI:
 285                 if (!ops->ndo_set_rx_mode ||
 286                     ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 287                         return -EINVAL;
 288                 if (!netif_device_present(dev))
 289                         return -ENODEV;
 290                 return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
 291
 292         case SIOCDELMULTI:
 293                 if (!ops->ndo_set_rx_mode ||
 294                     ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 295                         return -EINVAL;
 296                 if (!netif_device_present(dev))
 297                         return -ENODEV;
 298                 return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
 299
 300         case SIOCSIFTXQLEN:
 301                 if (ifr->ifr_qlen < 0)
 302                         return -EINVAL;
 303                 dev->tx_queue_len = ifr->ifr_qlen;
 304                 return 0;
 305
 306         case SIOCSIFNAME:
 307                 ifr->ifr_newname[IFNAMSIZ-1] = '\0';
 308                 return dev_change_name(dev, ifr->ifr_newname);
 309
 310         case SIOCSHWTSTAMP:
 311                 err = net_hwtstamp_validate(ifr);
 312                 if (err)
 313                         return err;
 314                 /* fall through */
 315
 316         /*
 317          *      Unknown or private ioctl
 318          */
 319         default:
 320                 if ((cmd >= SIOCDEVPRIVATE &&
 321                     cmd <= SIOCDEVPRIVATE + 15) ||
 322                     cmd == SIOCBONDENSLAVE ||
 323                     cmd == SIOCBONDRELEASE ||
 324                     cmd == SIOCBONDSETHWADDR ||
 325                     cmd == SIOCBONDSLAVEINFOQUERY ||
 326                     cmd == SIOCBONDINFOQUERY ||
 327                     cmd == SIOCBONDCHANGEACTIVE ||
 328                     cmd == SIOCGMIIPHY ||
 329                     cmd == SIOCGMIIREG ||
 330                     cmd == SIOCSMIIREG ||
 331                     cmd == SIOCBRADDIF ||
 332                     cmd == SIOCBRDELIF ||
 333                     cmd == SIOCSHWTSTAMP ||
 334                     cmd == SIOCGHWTSTAMP ||
 335                     cmd == SIOCWANDEV) {
 336                         err = -EOPNOTSUPP;
 337                         if (ops->ndo_do_ioctl) {
 338                                 if (netif_device_present(dev))
 339                                         err = ops->ndo_do_ioctl(dev, ifr, cmd);
 340                                 else
 341                                         err = -ENODEV;
 342                         }
 343                 } else
 344                         err = -EINVAL;
 345
 346         }
 347         return err;
 348 }
 349
 350 /**
 351  *      dev_load        - load a network module
 352  *      @net: the applicable net namespace
 353  *      @name: name of interface
 354  *
 355  *      If a network interface is not present and the process has suitable
 356  *      privileges this function loads the module. If module loading is not
 357  *      available in this kernel then it becomes a nop.
 358  */
 359
 360 void dev_load(struct net *net, const char *name)
 361 {
 362         struct net_device *dev;
 363         int no_module;
 364
 365         rcu_read_lock();
 366         dev = dev_get_by_name_rcu(net, name);
 367         rcu_read_unlock();
 368
 369         no_module = !dev;
 370         if (no_module && capable(CAP_NET_ADMIN))
 371                 no_module = request_module("netdev-%s", name);
 372         if (no_module && capable(CAP_SYS_MODULE))
 373                 request_module("%s", name);
 374 }
 375 EXPORT_SYMBOL(dev_load);
 376
 377 /*
 378  *      This function handles all "interface"-type I/O control requests. The actual
 379  *      'doing' part of this is dev_ifsioc above.
 380  */
 381
 382 /**
 383  *      dev_ioctl       -       network device ioctl
 384  *      @net: the applicable net namespace
 385  *      @cmd: command to issue
 386  *      @arg: pointer to a struct ifreq in user space
 387  *
 388  *      Issue ioctl functions to devices. This is normally called by the
 389  *      user space syscall interfaces but can sometimes be useful for
 390  *      other purposes. The return value is the return from the syscall if
 391  *      positive or a negative errno code on error.
 392  */
 393
 394 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 395 {
 396         struct ifreq ifr;
 397         int ret;
 398         char *colon;
 399
 400         /* One special case: SIOCGIFCONF takes ifconf argument
 401            and requires shared lock, because it sleeps writing
 402            to user space.
 403          */
 404
 405         if (cmd == SIOCGIFCONF) {
 406                 rtnl_lock();
 407                 ret = dev_ifconf(net, (char __user *) arg);
 408                 rtnl_unlock();
 409                 return ret;
 410         }
 411         if (cmd == SIOCGIFNAME)
 412                 return dev_ifname(net, (struct ifreq __user *)arg);
 413
 414         /*
 415          * Take care of Wireless Extensions. Unfortunately struct iwreq
 416          * isn't a proper subset of struct ifreq (it's 8 byte shorter)
 417          * so we need to treat it specially, otherwise applications may
 418          * fault if the struct they're passing happens to land at the
 419          * end of a mapped page.
 420          */
 421         if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
 422                 struct iwreq iwr;
 423
 424                 if (copy_from_user(&iwr, arg, sizeof(iwr)))
 425                         return -EFAULT;
 426
 427                 return wext_handle_ioctl(net, &iwr, cmd, arg);
 428         }
 429
 430         if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
 431                 return -EFAULT;
 432
 433         ifr.ifr_name[IFNAMSIZ-1] = 0;
 434
 435         colon = strchr(ifr.ifr_name, ':');
 436         if (colon)
 437                 *colon = 0;
 438
 439         /*
 440          *      See which interface the caller is talking about.
 441          */
 442
 443         switch (cmd) {
 444         /*
 445          *      These ioctl calls:
 446          *      - can be done by all.
 447          *      - atomic and do not require locking.
 448          *      - return a value
 449          */
 450         case SIOCGIFFLAGS:
 451         case SIOCGIFMETRIC:
 452         case SIOCGIFMTU:
 453         case SIOCGIFHWADDR:
 454         case SIOCGIFSLAVE:
 455         case SIOCGIFMAP:
 456         case SIOCGIFINDEX:
 457         case SIOCGIFTXQLEN:
 458                 dev_load(net, ifr.ifr_name);
 459                 rcu_read_lock();
 460                 ret = dev_ifsioc_locked(net, &ifr, cmd);
 461                 rcu_read_unlock();
 462                 if (!ret) {
 463                         if (colon)
 464                                 *colon = ':';
 465                         if (copy_to_user(arg, &ifr,
 466                                          sizeof(struct ifreq)))
 467                                 ret = -EFAULT;
 468                 }
 469                 return ret;
 470
 471         case SIOCETHTOOL:
 472                 dev_load(net, ifr.ifr_name);
 473                 rtnl_lock();
 474                 ret = dev_ethtool(net, &ifr);
 475                 rtnl_unlock();
 476                 if (!ret) {
 477                         if (colon)
 478                                 *colon = ':';
 479                         if (copy_to_user(arg, &ifr,
 480                                          sizeof(struct ifreq)))
 481                                 ret = -EFAULT;
 482                 }
 483                 return ret;
 484
 485         /*
 486          *      These ioctl calls:
 487          *      - require superuser power.
 488          *      - require strict serialization.
 489          *      - return a value
 490          */
 491         case SIOCGMIIPHY:
 492         case SIOCGMIIREG:
 493         case SIOCSIFNAME:
 494                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 495                         return -EPERM;
 496                 dev_load(net, ifr.ifr_name);
 497                 rtnl_lock();
 498                 ret = dev_ifsioc(net, &ifr, cmd);
 499                 rtnl_unlock();
 500                 if (!ret) {
 501                         if (colon)
 502                                 *colon = ':';
 503                         if (copy_to_user(arg, &ifr,
 504                                          sizeof(struct ifreq)))
 505                                 ret = -EFAULT;
 506                 }
 507                 return ret;
 508
 509         /*
 510          *      These ioctl calls:
 511          *      - require superuser power.
 512          *      - require strict serialization.
 513          *      - do not return a value
 514          */
 515         case SIOCSIFMAP:
 516         case SIOCSIFTXQLEN:
 517                 if (!capable(CAP_NET_ADMIN))
 518                         return -EPERM;
 519                 /* fall through */
 520         /*
 521          *      These ioctl calls:
 522          *      - require local superuser power.
 523          *      - require strict serialization.
 524          *      - do not return a value
 525          */
 526         case SIOCSIFFLAGS:
 527         case SIOCSIFMETRIC:
 528         case SIOCSIFMTU:
 529         case SIOCSIFHWADDR:
 530         case SIOCSIFSLAVE:
 531         case SIOCADDMULTI:
 532         case SIOCDELMULTI:
 533         case SIOCSIFHWBROADCAST:
 534         case SIOCSMIIREG:
 535         case SIOCBONDENSLAVE:
 536         case SIOCBONDRELEASE:
 537         case SIOCBONDSETHWADDR:
 538         case SIOCBONDCHANGEACTIVE:
 539         case SIOCBRADDIF:
 540         case SIOCBRDELIF:
 541         case SIOCSHWTSTAMP:
 542                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 543                         return -EPERM;
 544                 /* fall through */
 545         case SIOCBONDSLAVEINFOQUERY:
 546         case SIOCBONDINFOQUERY:
 547                 dev_load(net, ifr.ifr_name);
 548                 rtnl_lock();
 549                 ret = dev_ifsioc(net, &ifr, cmd);
 550                 rtnl_unlock();
 551                 return ret;
 552
 553         case SIOCGIFMEM:
 554                 /* Get the per device memory space. We can add this but
 555                  * currently do not support it */
 556         case SIOCSIFMEM:
 557                 /* Set the per device memory buffer space.
 558                  * Not applicable in our case */
 559         case SIOCSIFLINK:
 560                 return -ENOTTY;
 561
 562         /*
 563          *      Unknown or private ioctl.
 564          */
 565         default:
 566                 if (cmd == SIOCWANDEV ||
 567                     cmd == SIOCGHWTSTAMP ||
 568                     (cmd >= SIOCDEVPRIVATE &&
 569                      cmd <= SIOCDEVPRIVATE + 15)) {
 570                         dev_load(net, ifr.ifr_name);
 571                         rtnl_lock();
 572                         ret = dev_ifsioc(net, &ifr, cmd);
 573                         rtnl_unlock();
 574                         if (!ret && copy_to_user(arg, &ifr,
 575                                                  sizeof(struct ifreq)))
 576                                 ret = -EFAULT;
 577                         return ret;
 578                 }
 579                 return -ENOTTY;
 580         }
 581 }