net/wireless/wext-core.c

   1 /*
   2  * This file implement the Wireless Extensions core API.
   3  *
   4  * Authors :    Jean Tourrilhes - HPL - <jt@hpl.hp.com>
   5  * Copyright (c) 1997-2007 Jean Tourrilhes, All Rights Reserved.
   6  * Copyright    2009 Johannes Berg <johannes@sipsolutions.net>
   7  *
   8  * (As all part of the Linux kernel, this file is GPL)
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/netdevice.h>
  12 #include <linux/rtnetlink.h>
  13 #include <linux/slab.h>
  14 #include <linux/wireless.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/export.h>
  17 #include <net/cfg80211.h>
  18 #include <net/iw_handler.h>
  19 #include <net/netlink.h>
  20 #include <net/wext.h>
  21 #include <net/net_namespace.h>
  22
  23 typedef int (*wext_ioctl_func)(struct net_device *, struct iwreq *,
  24                                unsigned int, struct iw_request_info *,
  25                                iw_handler);
  26
  27
  28 /*
  29  * Meta-data about all the standard Wireless Extension request we
  30  * know about.
  31  */
  32 static const struct iw_ioctl_description standard_ioctl[] = {
  33         [IW_IOCTL_IDX(SIOCSIWCOMMIT)] = {
  34                 .header_type    = IW_HEADER_TYPE_NULL,
  35         },
  36         [IW_IOCTL_IDX(SIOCGIWNAME)] = {
  37                 .header_type    = IW_HEADER_TYPE_CHAR,
  38                 .flags          = IW_DESCR_FLAG_DUMP,
  39         },
  40         [IW_IOCTL_IDX(SIOCSIWNWID)] = {
  41                 .header_type    = IW_HEADER_TYPE_PARAM,
  42                 .flags          = IW_DESCR_FLAG_EVENT,
  43         },
  44         [IW_IOCTL_IDX(SIOCGIWNWID)] = {
  45                 .header_type    = IW_HEADER_TYPE_PARAM,
  46                 .flags          = IW_DESCR_FLAG_DUMP,
  47         },
  48         [IW_IOCTL_IDX(SIOCSIWFREQ)] = {
  49                 .header_type    = IW_HEADER_TYPE_FREQ,
  50                 .flags          = IW_DESCR_FLAG_EVENT,
  51         },
  52         [IW_IOCTL_IDX(SIOCGIWFREQ)] = {
  53                 .header_type    = IW_HEADER_TYPE_FREQ,
  54                 .flags          = IW_DESCR_FLAG_DUMP,
  55         },
  56         [IW_IOCTL_IDX(SIOCSIWMODE)] = {
  57                 .header_type    = IW_HEADER_TYPE_UINT,
  58                 .flags          = IW_DESCR_FLAG_EVENT,
  59         },
  60         [IW_IOCTL_IDX(SIOCGIWMODE)] = {
  61                 .header_type    = IW_HEADER_TYPE_UINT,
  62                 .flags          = IW_DESCR_FLAG_DUMP,
  63         },
  64         [IW_IOCTL_IDX(SIOCSIWSENS)] = {
  65                 .header_type    = IW_HEADER_TYPE_PARAM,
  66         },
  67         [IW_IOCTL_IDX(SIOCGIWSENS)] = {
  68                 .header_type    = IW_HEADER_TYPE_PARAM,
  69         },
  70         [IW_IOCTL_IDX(SIOCSIWRANGE)] = {
  71                 .header_type    = IW_HEADER_TYPE_NULL,
  72         },
  73         [IW_IOCTL_IDX(SIOCGIWRANGE)] = {
  74                 .header_type    = IW_HEADER_TYPE_POINT,
  75                 .token_size     = 1,
  76                 .max_tokens     = sizeof(struct iw_range),
  77                 .flags          = IW_DESCR_FLAG_DUMP,
  78         },
  79         [IW_IOCTL_IDX(SIOCSIWPRIV)] = {
  80                 .header_type    = IW_HEADER_TYPE_NULL,
  81         },
  82         [IW_IOCTL_IDX(SIOCGIWPRIV)] = { /* (handled directly by us) */
  83                 .header_type    = IW_HEADER_TYPE_POINT,
  84                 .token_size     = sizeof(struct iw_priv_args),
  85                 .max_tokens     = 16,
  86                 .flags          = IW_DESCR_FLAG_NOMAX,
  87         },
  88         [IW_IOCTL_IDX(SIOCSIWSTATS)] = {
  89                 .header_type    = IW_HEADER_TYPE_NULL,
  90         },
  91         [IW_IOCTL_IDX(SIOCGIWSTATS)] = { /* (handled directly by us) */
  92                 .header_type    = IW_HEADER_TYPE_POINT,
  93                 .token_size     = 1,
  94                 .max_tokens     = sizeof(struct iw_statistics),
  95                 .flags          = IW_DESCR_FLAG_DUMP,
  96         },
  97         [IW_IOCTL_IDX(SIOCSIWSPY)] = {
  98                 .header_type    = IW_HEADER_TYPE_POINT,
  99                 .token_size     = sizeof(struct sockaddr),
 100                 .max_tokens     = IW_MAX_SPY,
 101         },
 102         [IW_IOCTL_IDX(SIOCGIWSPY)] = {
 103                 .header_type    = IW_HEADER_TYPE_POINT,
 104                 .token_size     = sizeof(struct sockaddr) +
 105                                   sizeof(struct iw_quality),
 106                 .max_tokens     = IW_MAX_SPY,
 107         },
 108         [IW_IOCTL_IDX(SIOCSIWTHRSPY)] = {
 109                 .header_type    = IW_HEADER_TYPE_POINT,
 110                 .token_size     = sizeof(struct iw_thrspy),
 111                 .min_tokens     = 1,
 112                 .max_tokens     = 1,
 113         },
 114         [IW_IOCTL_IDX(SIOCGIWTHRSPY)] = {
 115                 .header_type    = IW_HEADER_TYPE_POINT,
 116                 .token_size     = sizeof(struct iw_thrspy),
 117                 .min_tokens     = 1,
 118                 .max_tokens     = 1,
 119         },
 120         [IW_IOCTL_IDX(SIOCSIWAP)] = {
 121                 .header_type    = IW_HEADER_TYPE_ADDR,
 122         },
 123         [IW_IOCTL_IDX(SIOCGIWAP)] = {
 124                 .header_type    = IW_HEADER_TYPE_ADDR,
 125                 .flags          = IW_DESCR_FLAG_DUMP,
 126         },
 127         [IW_IOCTL_IDX(SIOCSIWMLME)] = {
 128                 .header_type    = IW_HEADER_TYPE_POINT,
 129                 .token_size     = 1,
 130                 .min_tokens     = sizeof(struct iw_mlme),
 131                 .max_tokens     = sizeof(struct iw_mlme),
 132         },
 133         [IW_IOCTL_IDX(SIOCGIWAPLIST)] = {
 134                 .header_type    = IW_HEADER_TYPE_POINT,
 135                 .token_size     = sizeof(struct sockaddr) +
 136                                   sizeof(struct iw_quality),
 137                 .max_tokens     = IW_MAX_AP,
 138                 .flags          = IW_DESCR_FLAG_NOMAX,
 139         },
 140         [IW_IOCTL_IDX(SIOCSIWSCAN)] = {
 141                 .header_type    = IW_HEADER_TYPE_POINT,
 142                 .token_size     = 1,
 143                 .min_tokens     = 0,
 144                 .max_tokens     = sizeof(struct iw_scan_req),
 145         },
 146         [IW_IOCTL_IDX(SIOCGIWSCAN)] = {
 147                 .header_type    = IW_HEADER_TYPE_POINT,
 148                 .token_size     = 1,
 149                 .max_tokens     = IW_SCAN_MAX_DATA,
 150                 .flags          = IW_DESCR_FLAG_NOMAX,
 151         },
 152         [IW_IOCTL_IDX(SIOCSIWESSID)] = {
 153                 .header_type    = IW_HEADER_TYPE_POINT,
 154                 .token_size     = 1,
 155                 .max_tokens     = IW_ESSID_MAX_SIZE,
 156                 .flags          = IW_DESCR_FLAG_EVENT,
 157         },
 158         [IW_IOCTL_IDX(SIOCGIWESSID)] = {
 159                 .header_type    = IW_HEADER_TYPE_POINT,
 160                 .token_size     = 1,
 161                 .max_tokens     = IW_ESSID_MAX_SIZE,
 162                 .flags          = IW_DESCR_FLAG_DUMP,
 163         },
 164         [IW_IOCTL_IDX(SIOCSIWNICKN)] = {
 165                 .header_type    = IW_HEADER_TYPE_POINT,
 166                 .token_size     = 1,
 167                 .max_tokens     = IW_ESSID_MAX_SIZE,
 168         },
 169         [IW_IOCTL_IDX(SIOCGIWNICKN)] = {
 170                 .header_type    = IW_HEADER_TYPE_POINT,
 171                 .token_size     = 1,
 172                 .max_tokens     = IW_ESSID_MAX_SIZE,
 173         },
 174         [IW_IOCTL_IDX(SIOCSIWRATE)] = {
 175                 .header_type    = IW_HEADER_TYPE_PARAM,
 176         },
 177         [IW_IOCTL_IDX(SIOCGIWRATE)] = {
 178                 .header_type    = IW_HEADER_TYPE_PARAM,
 179         },
 180         [IW_IOCTL_IDX(SIOCSIWRTS)] = {
 181                 .header_type    = IW_HEADER_TYPE_PARAM,
 182         },
 183         [IW_IOCTL_IDX(SIOCGIWRTS)] = {
 184                 .header_type    = IW_HEADER_TYPE_PARAM,
 185         },
 186         [IW_IOCTL_IDX(SIOCSIWFRAG)] = {
 187                 .header_type    = IW_HEADER_TYPE_PARAM,
 188         },
 189         [IW_IOCTL_IDX(SIOCGIWFRAG)] = {
 190                 .header_type    = IW_HEADER_TYPE_PARAM,
 191         },
 192         [IW_IOCTL_IDX(SIOCSIWTXPOW)] = {
 193                 .header_type    = IW_HEADER_TYPE_PARAM,
 194         },
 195         [IW_IOCTL_IDX(SIOCGIWTXPOW)] = {
 196                 .header_type    = IW_HEADER_TYPE_PARAM,
 197         },
 198         [IW_IOCTL_IDX(SIOCSIWRETRY)] = {
 199                 .header_type    = IW_HEADER_TYPE_PARAM,
 200         },
 201         [IW_IOCTL_IDX(SIOCGIWRETRY)] = {
 202                 .header_type    = IW_HEADER_TYPE_PARAM,
 203         },
 204         [IW_IOCTL_IDX(SIOCSIWENCODE)] = {
 205                 .header_type    = IW_HEADER_TYPE_POINT,
 206                 .token_size     = 1,
 207                 .max_tokens     = IW_ENCODING_TOKEN_MAX,
 208                 .flags          = IW_DESCR_FLAG_EVENT | IW_DESCR_FLAG_RESTRICT,
 209         },
 210         [IW_IOCTL_IDX(SIOCGIWENCODE)] = {
 211                 .header_type    = IW_HEADER_TYPE_POINT,
 212                 .token_size     = 1,
 213                 .max_tokens     = IW_ENCODING_TOKEN_MAX,
 214                 .flags          = IW_DESCR_FLAG_DUMP | IW_DESCR_FLAG_RESTRICT,
 215         },
 216         [IW_IOCTL_IDX(SIOCSIWPOWER)] = {
 217                 .header_type    = IW_HEADER_TYPE_PARAM,
 218         },
 219         [IW_IOCTL_IDX(SIOCGIWPOWER)] = {
 220                 .header_type    = IW_HEADER_TYPE_PARAM,
 221         },
 222         [IW_IOCTL_IDX(SIOCSIWGENIE)] = {
 223                 .header_type    = IW_HEADER_TYPE_POINT,
 224                 .token_size     = 1,
 225                 .max_tokens     = IW_GENERIC_IE_MAX,
 226         },
 227         [IW_IOCTL_IDX(SIOCGIWGENIE)] = {
 228                 .header_type    = IW_HEADER_TYPE_POINT,
 229                 .token_size     = 1,
 230                 .max_tokens     = IW_GENERIC_IE_MAX,
 231         },
 232         [IW_IOCTL_IDX(SIOCSIWAUTH)] = {
 233                 .header_type    = IW_HEADER_TYPE_PARAM,
 234         },
 235         [IW_IOCTL_IDX(SIOCGIWAUTH)] = {
 236                 .header_type    = IW_HEADER_TYPE_PARAM,
 237         },
 238         [IW_IOCTL_IDX(SIOCSIWENCODEEXT)] = {
 239                 .header_type    = IW_HEADER_TYPE_POINT,
 240                 .token_size     = 1,
 241                 .min_tokens     = sizeof(struct iw_encode_ext),
 242                 .max_tokens     = sizeof(struct iw_encode_ext) +
 243                                   IW_ENCODING_TOKEN_MAX,
 244         },
 245         [IW_IOCTL_IDX(SIOCGIWENCODEEXT)] = {
 246                 .header_type    = IW_HEADER_TYPE_POINT,
 247                 .token_size     = 1,
 248                 .min_tokens     = sizeof(struct iw_encode_ext),
 249                 .max_tokens     = sizeof(struct iw_encode_ext) +
 250                                   IW_ENCODING_TOKEN_MAX,
 251         },
 252         [IW_IOCTL_IDX(SIOCSIWPMKSA)] = {
 253                 .header_type    = IW_HEADER_TYPE_POINT,
 254                 .token_size     = 1,
 255                 .min_tokens     = sizeof(struct iw_pmksa),
 256                 .max_tokens     = sizeof(struct iw_pmksa),
 257         },
 258 };
 259 static const unsigned standard_ioctl_num = ARRAY_SIZE(standard_ioctl);
 260
 261 /*
 262  * Meta-data about all the additional standard Wireless Extension events
 263  * we know about.
 264  */
 265 static const struct iw_ioctl_description standard_event[] = {
 266         [IW_EVENT_IDX(IWEVTXDROP)] = {
 267                 .header_type    = IW_HEADER_TYPE_ADDR,
 268         },
 269         [IW_EVENT_IDX(IWEVQUAL)] = {
 270                 .header_type    = IW_HEADER_TYPE_QUAL,
 271         },
 272         [IW_EVENT_IDX(IWEVCUSTOM)] = {
 273                 .header_type    = IW_HEADER_TYPE_POINT,
 274                 .token_size     = 1,
 275                 .max_tokens     = IW_CUSTOM_MAX,
 276         },
 277         [IW_EVENT_IDX(IWEVREGISTERED)] = {
 278                 .header_type    = IW_HEADER_TYPE_ADDR,
 279         },
 280         [IW_EVENT_IDX(IWEVEXPIRED)] = {
 281                 .header_type    = IW_HEADER_TYPE_ADDR,
 282         },
 283         [IW_EVENT_IDX(IWEVGENIE)] = {
 284                 .header_type    = IW_HEADER_TYPE_POINT,
 285                 .token_size     = 1,
 286                 .max_tokens     = IW_GENERIC_IE_MAX,
 287         },
 288         [IW_EVENT_IDX(IWEVMICHAELMICFAILURE)] = {
 289                 .header_type    = IW_HEADER_TYPE_POINT,
 290                 .token_size     = 1,
 291                 .max_tokens     = sizeof(struct iw_michaelmicfailure),
 292         },
 293         [IW_EVENT_IDX(IWEVASSOCREQIE)] = {
 294                 .header_type    = IW_HEADER_TYPE_POINT,
 295                 .token_size     = 1,
 296                 .max_tokens     = IW_GENERIC_IE_MAX,
 297         },
 298         [IW_EVENT_IDX(IWEVASSOCRESPIE)] = {
 299                 .header_type    = IW_HEADER_TYPE_POINT,
 300                 .token_size     = 1,
 301                 .max_tokens     = IW_GENERIC_IE_MAX,
 302         },
 303         [IW_EVENT_IDX(IWEVPMKIDCAND)] = {
 304                 .header_type    = IW_HEADER_TYPE_POINT,
 305                 .token_size     = 1,
 306                 .max_tokens     = sizeof(struct iw_pmkid_cand),
 307         },
 308 };
 309 static const unsigned standard_event_num = ARRAY_SIZE(standard_event);
 310
 311 /* Size (in bytes) of various events */
 312 static const int event_type_size[] = {
 313         IW_EV_LCP_LEN,                  /* IW_HEADER_TYPE_NULL */
 314         0,
 315         IW_EV_CHAR_LEN,                 /* IW_HEADER_TYPE_CHAR */
 316         0,
 317         IW_EV_UINT_LEN,                 /* IW_HEADER_TYPE_UINT */
 318         IW_EV_FREQ_LEN,                 /* IW_HEADER_TYPE_FREQ */
 319         IW_EV_ADDR_LEN,                 /* IW_HEADER_TYPE_ADDR */
 320         0,
 321         IW_EV_POINT_LEN,                /* Without variable payload */
 322         IW_EV_PARAM_LEN,                /* IW_HEADER_TYPE_PARAM */
 323         IW_EV_QUAL_LEN,                 /* IW_HEADER_TYPE_QUAL */
 324 };
 325
 326 #ifdef CONFIG_COMPAT
 327 static const int compat_event_type_size[] = {
 328         IW_EV_COMPAT_LCP_LEN,           /* IW_HEADER_TYPE_NULL */
 329         0,
 330         IW_EV_COMPAT_CHAR_LEN,          /* IW_HEADER_TYPE_CHAR */
 331         0,
 332         IW_EV_COMPAT_UINT_LEN,          /* IW_HEADER_TYPE_UINT */
 333         IW_EV_COMPAT_FREQ_LEN,          /* IW_HEADER_TYPE_FREQ */
 334         IW_EV_COMPAT_ADDR_LEN,          /* IW_HEADER_TYPE_ADDR */
 335         0,
 336         IW_EV_COMPAT_POINT_LEN,         /* Without variable payload */
 337         IW_EV_COMPAT_PARAM_LEN,         /* IW_HEADER_TYPE_PARAM */
 338         IW_EV_COMPAT_QUAL_LEN,          /* IW_HEADER_TYPE_QUAL */
 339 };
 340 #endif
 341
 342
 343 /* IW event code */
 344
 345 static int __net_init wext_pernet_init(struct net *net)
 346 {
 347         skb_queue_head_init(&net->wext_nlevents);
 348         return 0;
 349 }
 350
 351 static void __net_exit wext_pernet_exit(struct net *net)
 352 {
 353         skb_queue_purge(&net->wext_nlevents);
 354 }
 355
 356 static struct pernet_operations wext_pernet_ops = {
 357         .init = wext_pernet_init,
 358         .exit = wext_pernet_exit,
 359 };
 360
 361 static int __init wireless_nlevent_init(void)
 362 {
 363         return register_pernet_subsys(&wext_pernet_ops);
 364 }
 365
 366 subsys_initcall(wireless_nlevent_init);
 367
 368 /* Process events generated by the wireless layer or the driver. */
 369 static void wireless_nlevent_process(struct work_struct *work)
 370 {
 371         struct sk_buff *skb;
 372         struct net *net;
 373
 374         rtnl_lock();
 375
 376         for_each_net(net) {
 377                 while ((skb = skb_dequeue(&net->wext_nlevents)))
 378                         rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL,
 379                                     GFP_KERNEL);
 380         }
 381
 382         rtnl_unlock();
 383 }
 384
 385 static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);
 386
 387 static struct nlmsghdr *rtnetlink_ifinfo_prep(struct net_device *dev,
 388                                               struct sk_buff *skb)
 389 {
 390         struct ifinfomsg *r;
 391         struct nlmsghdr  *nlh;
 392
 393         nlh = nlmsg_put(skb, 0, 0, RTM_NEWLINK, sizeof(*r), 0);
 394         if (!nlh)
 395                 return NULL;
 396
 397         r = nlmsg_data(nlh);
 398         r->ifi_family = AF_UNSPEC;
 399         r->__ifi_pad = 0;
 400         r->ifi_type = dev->type;
 401         r->ifi_index = dev->ifindex;
 402         r->ifi_flags = dev_get_flags(dev);
 403         r->ifi_change = 0;      /* Wireless changes don't affect those flags */
 404
 405         NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
 406
 407         return nlh;
 408  nla_put_failure:
 409         nlmsg_cancel(skb, nlh);
 410         return NULL;
 411 }
 412
 413
 414 /*
 415  * Main event dispatcher. Called from other parts and drivers.
 416  * Send the event on the appropriate channels.
 417  * May be called from interrupt context.
 418  */
 419 void wireless_send_event(struct net_device *    dev,
 420                          unsigned int           cmd,
 421                          union iwreq_data *     wrqu,
 422                          const char *           extra)
 423 {
 424         const struct iw_ioctl_description *     descr = NULL;
 425         int extra_len = 0;
 426         struct iw_event  *event;                /* Mallocated whole event */
 427         int event_len;                          /* Its size */
 428         int hdr_len;                            /* Size of the event header */
 429         int wrqu_off = 0;                       /* Offset in wrqu */
 430         /* Don't "optimise" the following variable, it will crash */
 431         unsigned        cmd_index;              /* *MUST* be unsigned */
 432         struct sk_buff *skb;
 433         struct nlmsghdr *nlh;
 434         struct nlattr *nla;
 435 #ifdef CONFIG_COMPAT
 436         struct __compat_iw_event *compat_event;
 437         struct compat_iw_point compat_wrqu;
 438         struct sk_buff *compskb;
 439 #endif
 440
 441         /*
 442          * Nothing in the kernel sends scan events with data, be safe.
 443          * This is necessary because we cannot fix up scan event data
 444          * for compat, due to being contained in 'extra', but normally
 445          * applications are required to retrieve the scan data anyway
 446          * and no data is included in the event, this codifies that
 447          * practice.
 448          */
 449         if (WARN_ON(cmd == SIOCGIWSCAN && extra))
 450                 extra = NULL;
 451
 452         /* Get the description of the Event */
 453         if (cmd <= SIOCIWLAST) {
 454                 cmd_index = IW_IOCTL_IDX(cmd);
 455                 if (cmd_index < standard_ioctl_num)
 456                         descr = &(standard_ioctl[cmd_index]);
 457         } else {
 458                 cmd_index = IW_EVENT_IDX(cmd);
 459                 if (cmd_index < standard_event_num)
 460                         descr = &(standard_event[cmd_index]);
 461         }
 462         /* Don't accept unknown events */
 463         if (descr == NULL) {
 464                 /* Note : we don't return an error to the driver, because
 465                  * the driver would not know what to do about it. It can't
 466                  * return an error to the user, because the event is not
 467                  * initiated by a user request.
 468                  * The best the driver could do is to log an error message.
 469                  * We will do it ourselves instead...
 470                  */
 471                 netdev_err(dev, "(WE) : Invalid/Unknown Wireless Event (0x%04X)\n",
 472                            cmd);
 473                 return;
 474         }
 475
 476         /* Check extra parameters and set extra_len */
 477         if (descr->header_type == IW_HEADER_TYPE_POINT) {
 478                 /* Check if number of token fits within bounds */
 479                 if (wrqu->data.length > descr->max_tokens) {
 480                         netdev_err(dev, "(WE) : Wireless Event too big (%d)\n",
 481                                    wrqu->data.length);
 482                         return;
 483                 }
 484                 if (wrqu->data.length < descr->min_tokens) {
 485                         netdev_err(dev, "(WE) : Wireless Event too small (%d)\n",
 486                                    wrqu->data.length);
 487                         return;
 488                 }
 489                 /* Calculate extra_len - extra is NULL for restricted events */
 490                 if (extra != NULL)
 491                         extra_len = wrqu->data.length * descr->token_size;
 492                 /* Always at an offset in wrqu */
 493                 wrqu_off = IW_EV_POINT_OFF;
 494         }
 495
 496         /* Total length of the event */
 497         hdr_len = event_type_size[descr->header_type];
 498         event_len = hdr_len + extra_len;
 499
 500         /*
 501          * The problem for 64/32 bit.
 502          *
 503          * On 64-bit, a regular event is laid out as follows:
 504          *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
 505          *      | event.len | event.cmd |     p a d d i n g     |
 506          *      | wrqu data ... (with the correct size)         |
 507          *
 508          * This padding exists because we manipulate event->u,
 509          * and 'event' is not packed.
 510          *
 511          * An iw_point event is laid out like this instead:
 512          *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
 513          *      | event.len | event.cmd |     p a d d i n g     |
 514          *      | iwpnt.len | iwpnt.flg |     p a d d i n g     |
 515          *      | extra data  ...
 516          *
 517          * The second padding exists because struct iw_point is extended,
 518          * but this depends on the platform...
 519          *
 520          * On 32-bit, all the padding shouldn't be there.
 521          */
 522
 523         skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
 524         if (!skb)
 525                 return;
 526
 527         /* Send via the RtNetlink event channel */
 528         nlh = rtnetlink_ifinfo_prep(dev, skb);
 529         if (WARN_ON(!nlh)) {
 530                 kfree_skb(skb);
 531                 return;
 532         }
 533
 534         /* Add the wireless events in the netlink packet */
 535         nla = nla_reserve(skb, IFLA_WIRELESS, event_len);
 536         if (!nla) {
 537                 kfree_skb(skb);
 538                 return;
 539         }
 540         event = nla_data(nla);
 541
 542         /* Fill event - first clear to avoid data leaking */
 543         memset(event, 0, hdr_len);
 544         event->len = event_len;
 545         event->cmd = cmd;
 546         memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);
 547         if (extra_len)
 548                 memcpy(((char *) event) + hdr_len, extra, extra_len);
 549
 550         nlmsg_end(skb, nlh);
 551 #ifdef CONFIG_COMPAT
 552         hdr_len = compat_event_type_size[descr->header_type];
 553         event_len = hdr_len + extra_len;
 554
 555         compskb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
 556         if (!compskb) {
 557                 kfree_skb(skb);
 558                 return;
 559         }
 560
 561         /* Send via the RtNetlink event channel */
 562         nlh = rtnetlink_ifinfo_prep(dev, compskb);
 563         if (WARN_ON(!nlh)) {
 564                 kfree_skb(skb);
 565                 kfree_skb(compskb);
 566                 return;
 567         }
 568
 569         /* Add the wireless events in the netlink packet */
 570         nla = nla_reserve(compskb, IFLA_WIRELESS, event_len);
 571         if (!nla) {
 572                 kfree_skb(skb);
 573                 kfree_skb(compskb);
 574                 return;
 575         }
 576         compat_event = nla_data(nla);
 577
 578         compat_event->len = event_len;
 579         compat_event->cmd = cmd;
 580         if (descr->header_type == IW_HEADER_TYPE_POINT) {
 581                 compat_wrqu.length = wrqu->data.length;
 582                 compat_wrqu.flags = wrqu->data.flags;
 583                 memcpy(&compat_event->pointer,
 584                         ((char *) &compat_wrqu) + IW_EV_COMPAT_POINT_OFF,
 585                         hdr_len - IW_EV_COMPAT_LCP_LEN);
 586                 if (extra_len)
 587                         memcpy(((char *) compat_event) + hdr_len,
 588                                 extra, extra_len);
 589         } else {
 590                 /* extra_len must be zero, so no if (extra) needed */
 591                 memcpy(&compat_event->pointer, wrqu,
 592                         hdr_len - IW_EV_COMPAT_LCP_LEN);
 593         }
 594
 595         nlmsg_end(compskb, nlh);
 596
 597         skb_shinfo(skb)->frag_list = compskb;
 598 #endif
 599         skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
 600         schedule_work(&wireless_nlevent_work);
 601 }
 602 EXPORT_SYMBOL(wireless_send_event);
 603
 604
 605
 606 /* IW handlers */
 607
 608 struct iw_statistics *get_wireless_stats(struct net_device *dev)
 609 {
 610 #ifdef CONFIG_WIRELESS_EXT
 611         if ((dev->wireless_handlers != NULL) &&
 612            (dev->wireless_handlers->get_wireless_stats != NULL))
 613                 return dev->wireless_handlers->get_wireless_stats(dev);
 614 #endif
 615
 616 #ifdef CONFIG_CFG80211_WEXT
 617         if (dev->ieee80211_ptr &&
 618             dev->ieee80211_ptr->wiphy &&
 619             dev->ieee80211_ptr->wiphy->wext &&
 620             dev->ieee80211_ptr->wiphy->wext->get_wireless_stats)
 621                 return dev->ieee80211_ptr->wiphy->wext->get_wireless_stats(dev);
 622 #endif
 623
 624         /* not found */
 625         return NULL;
 626 }
 627
 628 static int iw_handler_get_iwstats(struct net_device *           dev,
 629                                   struct iw_request_info *      info,
 630                                   union iwreq_data *            wrqu,
 631                                   char *                        extra)
 632 {
 633         /* Get stats from the driver */
 634         struct iw_statistics *stats;
 635
 636         stats = get_wireless_stats(dev);
 637         if (stats) {
 638                 /* Copy statistics to extra */
 639                 memcpy(extra, stats, sizeof(struct iw_statistics));
 640                 wrqu->data.length = sizeof(struct iw_statistics);
 641
 642                 /* Check if we need to clear the updated flag */
 643                 if (wrqu->data.flags != 0)
 644                         stats->qual.updated &= ~IW_QUAL_ALL_UPDATED;
 645                 return 0;
 646         } else
 647                 return -EOPNOTSUPP;
 648 }
 649
 650 static iw_handler get_handler(struct net_device *dev, unsigned int cmd)
 651 {
 652         /* Don't "optimise" the following variable, it will crash */
 653         unsigned int    index;          /* *MUST* be unsigned */
 654         const struct iw_handler_def *handlers = NULL;
 655
 656 #ifdef CONFIG_CFG80211_WEXT
 657         if (dev->ieee80211_ptr && dev->ieee80211_ptr->wiphy)
 658                 handlers = dev->ieee80211_ptr->wiphy->wext;
 659 #endif
 660 #ifdef CONFIG_WIRELESS_EXT
 661         if (dev->wireless_handlers)
 662                 handlers = dev->wireless_handlers;
 663 #endif
 664
 665         if (!handlers)
 666                 return NULL;
 667
 668         /* Try as a standard command */
 669         index = IW_IOCTL_IDX(cmd);
 670         if (index < handlers->num_standard)
 671                 return handlers->standard[index];
 672
 673 #ifdef CONFIG_WEXT_PRIV
 674         /* Try as a private command */
 675         index = cmd - SIOCIWFIRSTPRIV;
 676         if (index < handlers->num_private)
 677                 return handlers->private[index];
 678 #endif
 679
 680         /* Not found */
 681         return NULL;
 682 }
 683
 684 static int ioctl_standard_iw_point(struct iw_point *iwp, unsigned int cmd,
 685                                    const struct iw_ioctl_description *descr,
 686                                    iw_handler handler, struct net_device *dev,
 687                                    struct iw_request_info *info)
 688 {
 689         int err, extra_size, user_length = 0, essid_compat = 0;
 690         char *extra;
 691
 692         /* Calculate space needed by arguments. Always allocate
 693          * for max space.
 694          */
 695         extra_size = descr->max_tokens * descr->token_size;
 696
 697         /* Check need for ESSID compatibility for WE < 21 */
 698         switch (cmd) {
 699         case SIOCSIWESSID:
 700         case SIOCGIWESSID:
 701         case SIOCSIWNICKN:
 702         case SIOCGIWNICKN:
 703                 if (iwp->length == descr->max_tokens + 1)
 704                         essid_compat = 1;
 705                 else if (IW_IS_SET(cmd) && (iwp->length != 0)) {
 706                         char essid[IW_ESSID_MAX_SIZE + 1];
 707                         unsigned int len;
 708                         len = iwp->length * descr->token_size;
 709
 710                         if (len > IW_ESSID_MAX_SIZE)
 711                                 return -EFAULT;
 712
 713                         err = copy_from_user(essid, iwp->pointer, len);
 714                         if (err)
 715                                 return -EFAULT;
 716
 717                         if (essid[iwp->length - 1] == '\0')
 718                                 essid_compat = 1;
 719                 }
 720                 break;
 721         default:
 722                 break;
 723         }
 724
 725         iwp->length -= essid_compat;
 726
 727         /* Check what user space is giving us */
 728         if (IW_IS_SET(cmd)) {
 729                 /* Check NULL pointer */
 730                 if (!iwp->pointer && iwp->length != 0)
 731                         return -EFAULT;
 732                 /* Check if number of token fits within bounds */
 733                 if (iwp->length > descr->max_tokens)
 734                         return -E2BIG;
 735                 if (iwp->length < descr->min_tokens)
 736                         return -EINVAL;
 737         } else {
 738                 /* Check NULL pointer */
 739                 if (!iwp->pointer)
 740                         return -EFAULT;
 741                 /* Save user space buffer size for checking */
 742                 user_length = iwp->length;
 743
 744                 /* Don't check if user_length > max to allow forward
 745                  * compatibility. The test user_length < min is
 746                  * implied by the test at the end.
 747                  */
 748
 749                 /* Support for very large requests */
 750                 if ((descr->flags & IW_DESCR_FLAG_NOMAX) &&
 751                     (user_length > descr->max_tokens)) {
 752                         /* Allow userspace to GET more than max so
 753                          * we can support any size GET requests.
 754                          * There is still a limit : -ENOMEM.
 755                          */
 756                         extra_size = user_length * descr->token_size;
 757
 758                         /* Note : user_length is originally a __u16,
 759                          * and token_size is controlled by us,
 760                          * so extra_size won't get negative and
 761                          * won't overflow...
 762                          */
 763                 }
 764         }
 765
 766         /* kzalloc() ensures NULL-termination for essid_compat. */
 767         extra = kzalloc(extra_size, GFP_KERNEL);
 768         if (!extra)
 769                 return -ENOMEM;
 770
 771         /* If it is a SET, get all the extra data in here */
 772         if (IW_IS_SET(cmd) && (iwp->length != 0)) {
 773                 if (copy_from_user(extra, iwp->pointer,
 774                                    iwp->length *
 775                                    descr->token_size)) {
 776                         err = -EFAULT;
 777                         goto out;
 778                 }
 779
 780                 if (cmd == SIOCSIWENCODEEXT) {
 781                         struct iw_encode_ext *ee = (void *) extra;
 782
 783                         if (iwp->length < sizeof(*ee) + ee->key_len)
 784                                 return -EFAULT;
 785                 }
 786         }
 787
 788         if (IW_IS_GET(cmd) && !(descr->flags & IW_DESCR_FLAG_NOMAX)) {
 789                 /*
 790                  * If this is a GET, but not NOMAX, it means that the extra
 791                  * data is not bounded by userspace, but by max_tokens. Thus
 792                  * set the length to max_tokens. This matches the extra data
 793                  * allocation.
 794                  * The driver should fill it with the number of tokens it
 795                  * provided, and it may check iwp->length rather than having
 796                  * knowledge of max_tokens. If the driver doesn't change the
 797                  * iwp->length, this ioctl just copies back max_token tokens
 798                  * filled with zeroes. Hopefully the driver isn't claiming
 799                  * them to be valid data.
 800                  */
 801                 iwp->length = descr->max_tokens;
 802         }
 803
 804         err = handler(dev, info, (union iwreq_data *) iwp, extra);
 805
 806         iwp->length += essid_compat;
 807
 808         /* If we have something to return to the user */
 809         if (!err && IW_IS_GET(cmd)) {
 810                 /* Check if there is enough buffer up there */
 811                 if (user_length < iwp->length) {
 812                         err = -E2BIG;
 813                         goto out;
 814                 }
 815
 816                 if (copy_to_user(iwp->pointer, extra,
 817                                  iwp->length *
 818                                  descr->token_size)) {
 819                         err = -EFAULT;
 820                         goto out;
 821                 }
 822         }
 823
 824         /* Generate an event to notify listeners of the change */
 825         if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
 826             ((err == 0) || (err == -EIWCOMMIT))) {
 827                 union iwreq_data *data = (union iwreq_data *) iwp;
 828
 829                 if (descr->flags & IW_DESCR_FLAG_RESTRICT)
 830                         /* If the event is restricted, don't
 831                          * export the payload.
 832                          */
 833                         wireless_send_event(dev, cmd, data, NULL);
 834                 else
 835                         wireless_send_event(dev, cmd, data, extra);
 836         }
 837
 838 out:
 839         kfree(extra);
 840         return err;
 841 }
 842
 843 /*
 844  * Call the commit handler in the driver
 845  * (if exist and if conditions are right)
 846  *
 847  * Note : our current commit strategy is currently pretty dumb,
 848  * but we will be able to improve on that...
 849  * The goal is to try to agreagate as many changes as possible
 850  * before doing the commit. Drivers that will define a commit handler
 851  * are usually those that need a reset after changing parameters, so
 852  * we want to minimise the number of reset.
 853  * A cool idea is to use a timer : at each "set" command, we re-set the
 854  * timer, when the timer eventually fires, we call the driver.
 855  * Hopefully, more on that later.
 856  *
 857  * Also, I'm waiting to see how many people will complain about the
 858  * netif_running(dev) test. I'm open on that one...
 859  * Hopefully, the driver will remember to do a commit in "open()" ;-)
 860  */
 861 int call_commit_handler(struct net_device *dev)
 862 {
 863 #ifdef CONFIG_WIRELESS_EXT
 864         if ((netif_running(dev)) &&
 865            (dev->wireless_handlers->standard[0] != NULL))
 866                 /* Call the commit handler on the driver */
 867                 return dev->wireless_handlers->standard[0](dev, NULL,
 868                                                            NULL, NULL);
 869         else
 870                 return 0;               /* Command completed successfully */
 871 #else
 872         /* cfg80211 has no commit */
 873         return 0;
 874 #endif
 875 }
 876
 877 /*
 878  * Main IOCTl dispatcher.
 879  * Check the type of IOCTL and call the appropriate wrapper...
 880  */
 881 static int wireless_process_ioctl(struct net *net, struct ifreq *ifr,
 882                                   unsigned int cmd,
 883                                   struct iw_request_info *info,
 884                                   wext_ioctl_func standard,
 885                                   wext_ioctl_func private)
 886 {
 887         struct iwreq *iwr = (struct iwreq *) ifr;
 888         struct net_device *dev;
 889         iw_handler      handler;
 890
 891         /* Permissions are already checked in dev_ioctl() before calling us.
 892          * The copy_to/from_user() of ifr is also dealt with in there */
 893
 894         /* Make sure the device exist */
 895         if ((dev = __dev_get_by_name(net, ifr->ifr_name)) == NULL)
 896                 return -ENODEV;
 897
 898         /* A bunch of special cases, then the generic case...
 899          * Note that 'cmd' is already filtered in dev_ioctl() with
 900          * (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
 901         if (cmd == SIOCGIWSTATS)
 902                 return standard(dev, iwr, cmd, info,
 903                                 &iw_handler_get_iwstats);
 904
 905 #ifdef CONFIG_WEXT_PRIV
 906         if (cmd == SIOCGIWPRIV && dev->wireless_handlers)
 907                 return standard(dev, iwr, cmd, info,
 908                                 iw_handler_get_private);
 909 #endif
 910
 911         /* Basic check */
 912         if (!netif_device_present(dev))
 913                 return -ENODEV;
 914
 915         /* New driver API : try to find the handler */
 916         handler = get_handler(dev, cmd);
 917         if (handler) {
 918                 /* Standard and private are not the same */
 919                 if (cmd < SIOCIWFIRSTPRIV)
 920                         return standard(dev, iwr, cmd, info, handler);
 921                 else if (private)
 922                         return private(dev, iwr, cmd, info, handler);
 923         }
 924         /* Old driver API : call driver ioctl handler */
 925         if (dev->netdev_ops->ndo_do_ioctl)
 926                 return dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
 927         return -EOPNOTSUPP;
 928 }
 929
 930 /* If command is `set a parameter', or `get the encoding parameters',
 931  * check if the user has the right to do it.
 932  */
 933 static int wext_permission_check(unsigned int cmd)
 934 {
 935         if ((IW_IS_SET(cmd) || cmd == SIOCGIWENCODE ||
 936              cmd == SIOCGIWENCODEEXT) &&
 937             !capable(CAP_NET_ADMIN))
 938                 return -EPERM;
 939
 940         return 0;
 941 }
 942
 943 /* entry point from dev ioctl */
 944 static int wext_ioctl_dispatch(struct net *net, struct ifreq *ifr,
 945                                unsigned int cmd, struct iw_request_info *info,
 946                                wext_ioctl_func standard,
 947                                wext_ioctl_func private)
 948 {
 949         int ret = wext_permission_check(cmd);
 950
 951         if (ret)
 952                 return ret;
 953
 954         dev_load(net, ifr->ifr_name);
 955         rtnl_lock();
 956         ret = wireless_process_ioctl(net, ifr, cmd, info, standard, private);
 957         rtnl_unlock();
 958
 959         return ret;
 960 }
 961
 962 /*
 963  * Wrapper to call a standard Wireless Extension handler.
 964  * We do various checks and also take care of moving data between
 965  * user space and kernel space.
 966  */
 967 static int ioctl_standard_call(struct net_device *      dev,
 968                                struct iwreq             *iwr,
 969                                unsigned int             cmd,
 970                                struct iw_request_info   *info,
 971                                iw_handler               handler)
 972 {
 973         const struct iw_ioctl_description *     descr;
 974         int                                     ret = -EINVAL;
 975
 976         /* Get the description of the IOCTL */
 977         if (IW_IOCTL_IDX(cmd) >= standard_ioctl_num)
 978                 return -EOPNOTSUPP;
 979         descr = &(standard_ioctl[IW_IOCTL_IDX(cmd)]);
 980
 981         /* Check if we have a pointer to user space data or not */
 982         if (descr->header_type != IW_HEADER_TYPE_POINT) {
 983
 984                 /* No extra arguments. Trivial to handle */
 985                 ret = handler(dev, info, &(iwr->u), NULL);
 986
 987                 /* Generate an event to notify listeners of the change */
 988                 if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
 989                    ((ret == 0) || (ret == -EIWCOMMIT)))
 990                         wireless_send_event(dev, cmd, &(iwr->u), NULL);
 991         } else {
 992                 ret = ioctl_standard_iw_point(&iwr->u.data, cmd, descr,
 993                                               handler, dev, info);
 994         }
 995
 996         /* Call commit handler if needed and defined */
 997         if (ret == -EIWCOMMIT)
 998                 ret = call_commit_handler(dev);
 999
1000         /* Here, we will generate the appropriate event if needed */
1001
1002         return ret;
1003 }
1004
1005
1006 int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
1007                       void __user *arg)
1008 {
1009         struct iw_request_info info = { .cmd = cmd, .flags = 0 };
1010         int ret;
1011
1012         ret = wext_ioctl_dispatch(net, ifr, cmd, &info,
1013                                   ioctl_standard_call,
1014                                   ioctl_private_call);
1015         if (ret >= 0 &&
1016             IW_IS_GET(cmd) &&
1017             copy_to_user(arg, ifr, sizeof(struct iwreq)))
1018                 return -EFAULT;
1019
1020         return ret;
1021 }
1022
1023 #ifdef CONFIG_COMPAT
1024 static int compat_standard_call(struct net_device       *dev,
1025                                 struct iwreq            *iwr,
1026                                 unsigned int            cmd,
1027                                 struct iw_request_info  *info,
1028                                 iw_handler              handler)
1029 {
1030         const struct iw_ioctl_description *descr;
1031         struct compat_iw_point *iwp_compat;
1032         struct iw_point iwp;
1033         int err;
1034
1035         descr = standard_ioctl + IW_IOCTL_IDX(cmd);
1036
1037         if (descr->header_type != IW_HEADER_TYPE_POINT)
1038                 return ioctl_standard_call(dev, iwr, cmd, info, handler);
1039
1040         iwp_compat = (struct compat_iw_point *) &iwr->u.data;
1041         iwp.pointer = compat_ptr(iwp_compat->pointer);
1042         iwp.length = iwp_compat->length;
1043         iwp.flags = iwp_compat->flags;
1044
1045         err = ioctl_standard_iw_point(&iwp, cmd, descr, handler, dev, info);
1046
1047         iwp_compat->pointer = ptr_to_compat(iwp.pointer);
1048         iwp_compat->length = iwp.length;
1049         iwp_compat->flags = iwp.flags;
1050
1051         return err;
1052 }
1053
1054 int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
1055                              unsigned long arg)
1056 {
1057         void __user *argp = (void __user *)arg;
1058         struct iw_request_info info;
1059         struct iwreq iwr;
1060         char *colon;
1061         int ret;
1062
1063         if (copy_from_user(&iwr, argp, sizeof(struct iwreq)))
1064                 return -EFAULT;
1065
1066         iwr.ifr_name[IFNAMSIZ-1] = 0;
1067         colon = strchr(iwr.ifr_name, ':');
1068         if (colon)
1069                 *colon = 0;
1070
1071         info.cmd = cmd;
1072         info.flags = IW_REQUEST_FLAG_COMPAT;
1073
1074         ret = wext_ioctl_dispatch(net, (struct ifreq *) &iwr, cmd, &info,
1075                                   compat_standard_call,
1076                                   compat_private_call);
1077
1078         if (ret >= 0 &&
1079             IW_IS_GET(cmd) &&
1080             copy_to_user(argp, &iwr, sizeof(struct iwreq)))
1081                 return -EFAULT;
1082
1083         return ret;
1084 }
1085 #endif