net/core/dev_ioctl.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/kmod.h>
   3 #include <linux/netdevice.h>
   4 #include <linux/etherdevice.h>
   5 #include <linux/rtnetlink.h>
   6 #include <linux/net_tstamp.h>
   7 #include <linux/wireless.h>
   8 #include <net/wext.h>
   9
  10 /*
  11  *      Map an interface index to its name (SIOCGIFNAME)
  12  */
  13
  14 /*
  15  *      We need this ioctl for efficient implementation of the
  16  *      if_indextoname() function required by the IPv6 API.  Without
  17  *      it, we would have to search all the interfaces to find a
  18  *      match.  --pb
  19  */
  20
  21 static int dev_ifname(struct net *net, struct ifreq __user *arg)
  22 {
  23         struct ifreq ifr;
  24         int error;
  25
  26         /*
  27          *      Fetch the caller's info block.
  28          */
  29
  30         if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
  31                 return -EFAULT;
  32         ifr.ifr_name[IFNAMSIZ-1] = 0;
  33
  34         error = netdev_get_name(net, ifr.ifr_name, ifr.ifr_ifindex);
  35         if (error)
  36                 return error;
  37
  38         if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
  39                 return -EFAULT;
  40         return 0;
  41 }
  42
  43 static gifconf_func_t *gifconf_list[NPROTO];
  44
  45 /**
  46  *      register_gifconf        -       register a SIOCGIF handler
  47  *      @family: Address family
  48  *      @gifconf: Function handler
  49  *
  50  *      Register protocol dependent address dumping routines. The handler
  51  *      that is passed must not be freed or reused until it has been replaced
  52  *      by another handler.
  53  */
  54 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
  55 {
  56         if (family >= NPROTO)
  57                 return -EINVAL;
  58         gifconf_list[family] = gifconf;
  59         return 0;
  60 }
  61 EXPORT_SYMBOL(register_gifconf);
  62
  63 /*
  64  *      Perform a SIOCGIFCONF call. This structure will change
  65  *      size eventually, and there is nothing I can do about it.
  66  *      Thus we will need a 'compatibility mode'.
  67  */
  68
  69 static int dev_ifconf(struct net *net, char __user *arg)
  70 {
  71         struct ifconf ifc;
  72         struct net_device *dev;
  73         char __user *pos;
  74         int len;
  75         int total;
  76         int i;
  77
  78         /*
  79          *      Fetch the caller's info block.
  80          */
  81
  82         if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
  83                 return -EFAULT;
  84
  85         pos = ifc.ifc_buf;
  86         len = ifc.ifc_len;
  87
  88         /*
  89          *      Loop over the interfaces, and write an info block for each.
  90          */
  91
  92         total = 0;
  93         for_each_netdev(net, dev) {
  94                 for (i = 0; i < NPROTO; i++) {
  95                         if (gifconf_list[i]) {
  96                                 int done;
  97                                 if (!pos)
  98                                         done = gifconf_list[i](dev, NULL, 0);
  99                                 else
 100                                         done = gifconf_list[i](dev, pos + total,
 101                                                                len - total);
 102                                 if (done < 0)
 103                                         return -EFAULT;
 104                                 total += done;
 105                         }
 106                 }
 107         }
 108
 109         /*
 110          *      All done.  Write the updated control block back to the caller.
 111          */
 112         ifc.ifc_len = total;
 113
 114         /*
 115          *      Both BSD and Solaris return 0 here, so we do too.
 116          */
 117         return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
 118 }
 119
 120 /*
 121  *      Perform the SIOCxIFxxx calls, inside rcu_read_lock()
 122  */
 123 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
 124 {
 125         int err;
 126         struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
 127
 128         if (!dev)
 129                 return -ENODEV;
 130
 131         switch (cmd) {
 132         case SIOCGIFFLAGS:      /* Get interface flags */
 133                 ifr->ifr_flags = (short) dev_get_flags(dev);
 134                 return 0;
 135
 136         case SIOCGIFMETRIC:     /* Get the metric on the interface
 137                                    (currently unused) */
 138                 ifr->ifr_metric = 0;
 139                 return 0;
 140
 141         case SIOCGIFMTU:        /* Get the MTU of a device */
 142                 ifr->ifr_mtu = dev->mtu;
 143                 return 0;
 144
 145         case SIOCGIFHWADDR:
 146                 if (!dev->addr_len)
 147                         memset(ifr->ifr_hwaddr.sa_data, 0,
 148                                sizeof(ifr->ifr_hwaddr.sa_data));
 149                 else
 150                         memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
 151                                min(sizeof(ifr->ifr_hwaddr.sa_data),
 152                                    (size_t)dev->addr_len));
 153                 ifr->ifr_hwaddr.sa_family = dev->type;
 154                 return 0;
 155
 156         case SIOCGIFSLAVE:
 157                 err = -EINVAL;
 158                 break;
 159
 160         case SIOCGIFMAP:
 161                 ifr->ifr_map.mem_start = dev->mem_start;
 162                 ifr->ifr_map.mem_end   = dev->mem_end;
 163                 ifr->ifr_map.base_addr = dev->base_addr;
 164                 ifr->ifr_map.irq       = dev->irq;
 165                 ifr->ifr_map.dma       = dev->dma;
 166                 ifr->ifr_map.port      = dev->if_port;
 167                 return 0;
 168
 169         case SIOCGIFINDEX:
 170                 ifr->ifr_ifindex = dev->ifindex;
 171                 return 0;
 172
 173         case SIOCGIFTXQLEN:
 174                 ifr->ifr_qlen = dev->tx_queue_len;
 175                 return 0;
 176
 177         default:
 178                 /* dev_ioctl() should ensure this case
 179                  * is never reached
 180                  */
 181                 WARN_ON(1);
 182                 err = -ENOTTY;
 183                 break;
 184
 185         }
 186         return err;
 187 }
 188
 189 static int net_hwtstamp_validate(struct ifreq *ifr)
 190 {
 191         struct hwtstamp_config cfg;
 192         enum hwtstamp_tx_types tx_type;
 193         enum hwtstamp_rx_filters rx_filter;
 194         int tx_type_valid = 0;
 195         int rx_filter_valid = 0;
 196
 197         if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
 198                 return -EFAULT;
 199
 200         if (cfg.flags) /* reserved for future extensions */
 201                 return -EINVAL;
 202
 203         tx_type = cfg.tx_type;
 204         rx_filter = cfg.rx_filter;
 205
 206         switch (tx_type) {
 207         case HWTSTAMP_TX_OFF:
 208         case HWTSTAMP_TX_ON:
 209         case HWTSTAMP_TX_ONESTEP_SYNC:
 210                 tx_type_valid = 1;
 211                 break;
 212         }
 213
 214         switch (rx_filter) {
 215         case HWTSTAMP_FILTER_NONE:
 216         case HWTSTAMP_FILTER_ALL:
 217         case HWTSTAMP_FILTER_SOME:
 218         case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
 219         case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
 220         case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
 221         case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
 222         case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
 223         case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
 224         case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
 225         case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
 226         case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
 227         case HWTSTAMP_FILTER_PTP_V2_EVENT:
 228         case HWTSTAMP_FILTER_PTP_V2_SYNC:
 229         case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
 230         case HWTSTAMP_FILTER_NTP_ALL:
 231                 rx_filter_valid = 1;
 232                 break;
 233         }
 234
 235         if (!tx_type_valid || !rx_filter_valid)
 236                 return -ERANGE;
 237
 238         return 0;
 239 }
 240
 241 /*
 242  *      Perform the SIOCxIFxxx calls, inside rtnl_lock()
 243  */
 244 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
 245 {
 246         int err;
 247         struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
 248         const struct net_device_ops *ops;
 249
 250         if (!dev)
 251                 return -ENODEV;
 252
 253         ops = dev->netdev_ops;
 254
 255         switch (cmd) {
 256         case SIOCSIFFLAGS:      /* Set interface flags */
 257                 return dev_change_flags(dev, ifr->ifr_flags);
 258
 259         case SIOCSIFMETRIC:     /* Set the metric on the interface
 260                                    (currently unused) */
 261                 return -EOPNOTSUPP;
 262
 263         case SIOCSIFMTU:        /* Set the MTU of a device */
 264                 return dev_set_mtu(dev, ifr->ifr_mtu);
 265
 266         case SIOCSIFHWADDR:
 267                 if (dev->addr_len > sizeof(struct sockaddr))
 268                         return -EINVAL;
 269                 return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
 270
 271         case SIOCSIFHWBROADCAST:
 272                 if (ifr->ifr_hwaddr.sa_family != dev->type)
 273                         return -EINVAL;
 274                 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
 275                        min(sizeof(ifr->ifr_hwaddr.sa_data),
 276                            (size_t)dev->addr_len));
 277                 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 278                 return 0;
 279
 280         case SIOCSIFMAP:
 281                 if (ops->ndo_set_config) {
 282                         if (!netif_device_present(dev))
 283                                 return -ENODEV;
 284                         return ops->ndo_set_config(dev, &ifr->ifr_map);
 285                 }
 286                 return -EOPNOTSUPP;
 287
 288         case SIOCADDMULTI:
 289                 if (!ops->ndo_set_rx_mode ||
 290                     ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 291                         return -EINVAL;
 292                 if (!netif_device_present(dev))
 293                         return -ENODEV;
 294                 return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
 295
 296         case SIOCDELMULTI:
 297                 if (!ops->ndo_set_rx_mode ||
 298                     ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 299                         return -EINVAL;
 300                 if (!netif_device_present(dev))
 301                         return -ENODEV;
 302                 return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
 303
 304         case SIOCSIFTXQLEN:
 305                 if (ifr->ifr_qlen < 0)
 306                         return -EINVAL;
 307                 if (dev->tx_queue_len ^ ifr->ifr_qlen) {
 308                         unsigned int orig_len = dev->tx_queue_len;
 309
 310                         dev->tx_queue_len = ifr->ifr_qlen;
 311                         err = call_netdevice_notifiers(
 312                                         NETDEV_CHANGE_TX_QUEUE_LEN, dev);
 313                         err = notifier_to_errno(err);
 314                         if (err) {
 315                                 dev->tx_queue_len = orig_len;
 316                                 return err;
 317                         }
 318                 }
 319                 return 0;
 320
 321         case SIOCSIFNAME:
 322                 ifr->ifr_newname[IFNAMSIZ-1] = '\0';
 323                 return dev_change_name(dev, ifr->ifr_newname);
 324
 325         case SIOCSHWTSTAMP:
 326                 err = net_hwtstamp_validate(ifr);
 327                 if (err)
 328                         return err;
 329                 /* fall through */
 330
 331         /*
 332          *      Unknown or private ioctl
 333          */
 334         default:
 335                 if ((cmd >= SIOCDEVPRIVATE &&
 336                     cmd <= SIOCDEVPRIVATE + 15) ||
 337                     cmd == SIOCBONDENSLAVE ||
 338                     cmd == SIOCBONDRELEASE ||
 339                     cmd == SIOCBONDSETHWADDR ||
 340                     cmd == SIOCBONDSLAVEINFOQUERY ||
 341                     cmd == SIOCBONDINFOQUERY ||
 342                     cmd == SIOCBONDCHANGEACTIVE ||
 343                     cmd == SIOCGMIIPHY ||
 344                     cmd == SIOCGMIIREG ||
 345                     cmd == SIOCSMIIREG ||
 346                     cmd == SIOCBRADDIF ||
 347                     cmd == SIOCBRDELIF ||
 348                     cmd == SIOCSHWTSTAMP ||
 349                     cmd == SIOCGHWTSTAMP ||
 350                     cmd == SIOCWANDEV) {
 351                         err = -EOPNOTSUPP;
 352                         if (ops->ndo_do_ioctl) {
 353                                 if (netif_device_present(dev))
 354                                         err = ops->ndo_do_ioctl(dev, ifr, cmd);
 355                                 else
 356                                         err = -ENODEV;
 357                         }
 358                 } else
 359                         err = -EINVAL;
 360
 361         }
 362         return err;
 363 }
 364
 365 /**
 366  *      dev_load        - load a network module
 367  *      @net: the applicable net namespace
 368  *      @name: name of interface
 369  *
 370  *      If a network interface is not present and the process has suitable
 371  *      privileges this function loads the module. If module loading is not
 372  *      available in this kernel then it becomes a nop.
 373  */
 374
 375 void dev_load(struct net *net, const char *name)
 376 {
 377         struct net_device *dev;
 378         int no_module;
 379
 380         rcu_read_lock();
 381         dev = dev_get_by_name_rcu(net, name);
 382         rcu_read_unlock();
 383
 384         no_module = !dev;
 385         if (no_module && capable(CAP_NET_ADMIN))
 386                 no_module = request_module("netdev-%s", name);
 387         if (no_module && capable(CAP_SYS_MODULE))
 388                 request_module("%s", name);
 389 }
 390 EXPORT_SYMBOL(dev_load);
 391
 392 /*
 393  *      This function handles all "interface"-type I/O control requests. The actual
 394  *      'doing' part of this is dev_ifsioc above.
 395  */
 396
 397 /**
 398  *      dev_ioctl       -       network device ioctl
 399  *      @net: the applicable net namespace
 400  *      @cmd: command to issue
 401  *      @arg: pointer to a struct ifreq in user space
 402  *
 403  *      Issue ioctl functions to devices. This is normally called by the
 404  *      user space syscall interfaces but can sometimes be useful for
 405  *      other purposes. The return value is the return from the syscall if
 406  *      positive or a negative errno code on error.
 407  */
 408
 409 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 410 {
 411         struct ifreq ifr;
 412         int ret;
 413         char *colon;
 414
 415         /* One special case: SIOCGIFCONF takes ifconf argument
 416            and requires shared lock, because it sleeps writing
 417            to user space.
 418          */
 419
 420         if (cmd == SIOCGIFCONF) {
 421                 rtnl_lock();
 422                 ret = dev_ifconf(net, (char __user *) arg);
 423                 rtnl_unlock();
 424                 return ret;
 425         }
 426         if (cmd == SIOCGIFNAME)
 427                 return dev_ifname(net, (struct ifreq __user *)arg);
 428
 429         /*
 430          * Take care of Wireless Extensions. Unfortunately struct iwreq
 431          * isn't a proper subset of struct ifreq (it's 8 byte shorter)
 432          * so we need to treat it specially, otherwise applications may
 433          * fault if the struct they're passing happens to land at the
 434          * end of a mapped page.
 435          */
 436         if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
 437                 struct iwreq iwr;
 438
 439                 if (copy_from_user(&iwr, arg, sizeof(iwr)))
 440                         return -EFAULT;
 441
 442                 iwr.ifr_name[sizeof(iwr.ifr_name) - 1] = 0;
 443
 444                 return wext_handle_ioctl(net, &iwr, cmd, arg);
 445         }
 446
 447         if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
 448                 return -EFAULT;
 449
 450         ifr.ifr_name[IFNAMSIZ-1] = 0;
 451
 452         colon = strchr(ifr.ifr_name, ':');
 453         if (colon)
 454                 *colon = 0;
 455
 456         /*
 457          *      See which interface the caller is talking about.
 458          */
 459
 460         switch (cmd) {
 461         /*
 462          *      These ioctl calls:
 463          *      - can be done by all.
 464          *      - atomic and do not require locking.
 465          *      - return a value
 466          */
 467         case SIOCGIFFLAGS:
 468         case SIOCGIFMETRIC:
 469         case SIOCGIFMTU:
 470         case SIOCGIFHWADDR:
 471         case SIOCGIFSLAVE:
 472         case SIOCGIFMAP:
 473         case SIOCGIFINDEX:
 474         case SIOCGIFTXQLEN:
 475                 dev_load(net, ifr.ifr_name);
 476                 rcu_read_lock();
 477                 ret = dev_ifsioc_locked(net, &ifr, cmd);
 478                 rcu_read_unlock();
 479                 if (!ret) {
 480                         if (colon)
 481                                 *colon = ':';
 482                         if (copy_to_user(arg, &ifr,
 483                                          sizeof(struct ifreq)))
 484                                 ret = -EFAULT;
 485                 }
 486                 return ret;
 487
 488         case SIOCETHTOOL:
 489                 dev_load(net, ifr.ifr_name);
 490                 rtnl_lock();
 491                 ret = dev_ethtool(net, &ifr);
 492                 rtnl_unlock();
 493                 if (!ret) {
 494                         if (colon)
 495                                 *colon = ':';
 496                         if (copy_to_user(arg, &ifr,
 497                                          sizeof(struct ifreq)))
 498                                 ret = -EFAULT;
 499                 }
 500                 return ret;
 501
 502         /*
 503          *      These ioctl calls:
 504          *      - require superuser power.
 505          *      - require strict serialization.
 506          *      - return a value
 507          */
 508         case SIOCGMIIPHY:
 509         case SIOCGMIIREG:
 510         case SIOCSIFNAME:
 511                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 512                         return -EPERM;
 513                 dev_load(net, ifr.ifr_name);
 514                 rtnl_lock();
 515                 ret = dev_ifsioc(net, &ifr, cmd);
 516                 rtnl_unlock();
 517                 if (!ret) {
 518                         if (colon)
 519                                 *colon = ':';
 520                         if (copy_to_user(arg, &ifr,
 521                                          sizeof(struct ifreq)))
 522                                 ret = -EFAULT;
 523                 }
 524                 return ret;
 525
 526         /*
 527          *      These ioctl calls:
 528          *      - require superuser power.
 529          *      - require strict serialization.
 530          *      - do not return a value
 531          */
 532         case SIOCSIFMAP:
 533         case SIOCSIFTXQLEN:
 534                 if (!capable(CAP_NET_ADMIN))
 535                         return -EPERM;
 536                 /* fall through */
 537         /*
 538          *      These ioctl calls:
 539          *      - require local superuser power.
 540          *      - require strict serialization.
 541          *      - do not return a value
 542          */
 543         case SIOCSIFFLAGS:
 544         case SIOCSIFMETRIC:
 545         case SIOCSIFMTU:
 546         case SIOCSIFHWADDR:
 547         case SIOCSIFSLAVE:
 548         case SIOCADDMULTI:
 549         case SIOCDELMULTI:
 550         case SIOCSIFHWBROADCAST:
 551         case SIOCSMIIREG:
 552         case SIOCBONDENSLAVE:
 553         case SIOCBONDRELEASE:
 554         case SIOCBONDSETHWADDR:
 555         case SIOCBONDCHANGEACTIVE:
 556         case SIOCBRADDIF:
 557         case SIOCBRDELIF:
 558         case SIOCSHWTSTAMP:
 559                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 560                         return -EPERM;
 561                 /* fall through */
 562         case SIOCBONDSLAVEINFOQUERY:
 563         case SIOCBONDINFOQUERY:
 564                 dev_load(net, ifr.ifr_name);
 565                 rtnl_lock();
 566                 ret = dev_ifsioc(net, &ifr, cmd);
 567                 rtnl_unlock();
 568                 return ret;
 569
 570         case SIOCGIFMEM:
 571                 /* Get the per device memory space. We can add this but
 572                  * currently do not support it */
 573         case SIOCSIFMEM:
 574                 /* Set the per device memory buffer space.
 575                  * Not applicable in our case */
 576         case SIOCSIFLINK:
 577                 return -ENOTTY;
 578
 579         /*
 580          *      Unknown or private ioctl.
 581          */
 582         default:
 583                 if (cmd == SIOCWANDEV ||
 584                     cmd == SIOCGHWTSTAMP ||
 585                     (cmd >= SIOCDEVPRIVATE &&
 586                      cmd <= SIOCDEVPRIVATE + 15)) {
 587                         dev_load(net, ifr.ifr_name);
 588                         rtnl_lock();
 589                         ret = dev_ifsioc(net, &ifr, cmd);
 590                         rtnl_unlock();
 591                         if (!ret && copy_to_user(arg, &ifr,
 592                                                  sizeof(struct ifreq)))
 593                                 ret = -EFAULT;
 594                         return ret;
 595                 }
 596                 return -ENOTTY;
 597         }
 598 }