linux/net/wireless/wext-core.c
<<
>>
Prefs
   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
  23typedef 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 */
  32static 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};
 259static const unsigned int 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 */
 265static 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};
 309static const unsigned int standard_event_num = ARRAY_SIZE(standard_event);
 310
 311/* Size (in bytes) of various events */
 312static 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
 327static 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
 345static int __net_init wext_pernet_init(struct net *net)
 346{
 347        skb_queue_head_init(&net->wext_nlevents);
 348        return 0;
 349}
 350
 351static void __net_exit wext_pernet_exit(struct net *net)
 352{
 353        skb_queue_purge(&net->wext_nlevents);
 354}
 355
 356static struct pernet_operations wext_pernet_ops = {
 357        .init = wext_pernet_init,
 358        .exit = wext_pernet_exit,
 359};
 360
 361static int __init wireless_nlevent_init(void)
 362{
 363        return register_pernet_subsys(&wext_pernet_ops);
 364}
 365
 366subsys_initcall(wireless_nlevent_init);
 367
 368/* Process events generated by the wireless layer or the driver. */
 369static 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
 385static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);
 386
 387static 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        if (nla_put_string(skb, IFLA_IFNAME, dev->name))
 406                goto nla_put_failure;
 407
 408        return nlh;
 409 nla_put_failure:
 410        nlmsg_cancel(skb, nlh);
 411        return NULL;
 412}
 413
 414
 415/*
 416 * Main event dispatcher. Called from other parts and drivers.
 417 * Send the event on the appropriate channels.
 418 * May be called from interrupt context.
 419 */
 420void wireless_send_event(struct net_device *    dev,
 421                         unsigned int           cmd,
 422                         union iwreq_data *     wrqu,
 423                         const char *           extra)
 424{
 425        const struct iw_ioctl_description *     descr = NULL;
 426        int extra_len = 0;
 427        struct iw_event  *event;                /* Mallocated whole event */
 428        int event_len;                          /* Its size */
 429        int hdr_len;                            /* Size of the event header */
 430        int wrqu_off = 0;                       /* Offset in wrqu */
 431        /* Don't "optimise" the following variable, it will crash */
 432        unsigned int    cmd_index;              /* *MUST* be unsigned */
 433        struct sk_buff *skb;
 434        struct nlmsghdr *nlh;
 435        struct nlattr *nla;
 436#ifdef CONFIG_COMPAT
 437        struct __compat_iw_event *compat_event;
 438        struct compat_iw_point compat_wrqu;
 439        struct sk_buff *compskb;
 440#endif
 441
 442        /*
 443         * Nothing in the kernel sends scan events with data, be safe.
 444         * This is necessary because we cannot fix up scan event data
 445         * for compat, due to being contained in 'extra', but normally
 446         * applications are required to retrieve the scan data anyway
 447         * and no data is included in the event, this codifies that
 448         * practice.
 449         */
 450        if (WARN_ON(cmd == SIOCGIWSCAN && extra))
 451                extra = NULL;
 452
 453        /* Get the description of the Event */
 454        if (cmd <= SIOCIWLAST) {
 455                cmd_index = IW_IOCTL_IDX(cmd);
 456                if (cmd_index < standard_ioctl_num)
 457                        descr = &(standard_ioctl[cmd_index]);
 458        } else {
 459                cmd_index = IW_EVENT_IDX(cmd);
 460                if (cmd_index < standard_event_num)
 461                        descr = &(standard_event[cmd_index]);
 462        }
 463        /* Don't accept unknown events */
 464        if (descr == NULL) {
 465                /* Note : we don't return an error to the driver, because
 466                 * the driver would not know what to do about it. It can't
 467                 * return an error to the user, because the event is not
 468                 * initiated by a user request.
 469                 * The best the driver could do is to log an error message.
 470                 * We will do it ourselves instead...
 471                 */
 472                netdev_err(dev, "(WE) : Invalid/Unknown Wireless Event (0x%04X)\n",
 473                           cmd);
 474                return;
 475        }
 476
 477        /* Check extra parameters and set extra_len */
 478        if (descr->header_type == IW_HEADER_TYPE_POINT) {
 479                /* Check if number of token fits within bounds */
 480                if (wrqu->data.length > descr->max_tokens) {
 481                        netdev_err(dev, "(WE) : Wireless Event (cmd=0x%04X) too big (%d)\n",
 482                                   cmd, wrqu->data.length);
 483                        return;
 484                }
 485                if (wrqu->data.length < descr->min_tokens) {
 486                        netdev_err(dev, "(WE) : Wireless Event (cmd=0x%04X) too small (%d)\n",
 487                                   cmd, wrqu->data.length);
 488                        return;
 489                }
 490                /* Calculate extra_len - extra is NULL for restricted events */
 491                if (extra != NULL)
 492                        extra_len = wrqu->data.length * descr->token_size;
 493                /* Always at an offset in wrqu */
 494                wrqu_off = IW_EV_POINT_OFF;
 495        }
 496
 497        /* Total length of the event */
 498        hdr_len = event_type_size[descr->header_type];
 499        event_len = hdr_len + extra_len;
 500
 501        /*
 502         * The problem for 64/32 bit.
 503         *
 504         * On 64-bit, a regular event is laid out as follows:
 505         *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
 506         *      | event.len | event.cmd |     p a d d i n g     |
 507         *      | wrqu data ... (with the correct size)         |
 508         *
 509         * This padding exists because we manipulate event->u,
 510         * and 'event' is not packed.
 511         *
 512         * An iw_point event is laid out like this instead:
 513         *      |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
 514         *      | event.len | event.cmd |     p a d d i n g     |
 515         *      | iwpnt.len | iwpnt.flg |     p a d d i n g     |
 516         *      | extra data  ...
 517         *
 518         * The second padding exists because struct iw_point is extended,
 519         * but this depends on the platform...
 520         *
 521         * On 32-bit, all the padding shouldn't be there.
 522         */
 523
 524        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
 525        if (!skb)
 526                return;
 527
 528        /* Send via the RtNetlink event channel */
 529        nlh = rtnetlink_ifinfo_prep(dev, skb);
 530        if (WARN_ON(!nlh)) {
 531                kfree_skb(skb);
 532                return;
 533        }
 534
 535        /* Add the wireless events in the netlink packet */
 536        nla = nla_reserve(skb, IFLA_WIRELESS, event_len);
 537        if (!nla) {
 538                kfree_skb(skb);
 539                return;
 540        }
 541        event = nla_data(nla);
 542
 543        /* Fill event - first clear to avoid data leaking */
 544        memset(event, 0, hdr_len);
 545        event->len = event_len;
 546        event->cmd = cmd;
 547        memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);
 548        if (extra_len)
 549                memcpy(((char *) event) + hdr_len, extra, extra_len);
 550
 551        nlmsg_end(skb, nlh);
 552#ifdef CONFIG_COMPAT
 553        hdr_len = compat_event_type_size[descr->header_type];
 554        event_len = hdr_len + extra_len;
 555
 556        compskb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
 557        if (!compskb) {
 558                kfree_skb(skb);
 559                return;
 560        }
 561
 562        /* Send via the RtNetlink event channel */
 563        nlh = rtnetlink_ifinfo_prep(dev, compskb);
 564        if (WARN_ON(!nlh)) {
 565                kfree_skb(skb);
 566                kfree_skb(compskb);
 567                return;
 568        }
 569
 570        /* Add the wireless events in the netlink packet */
 571        nla = nla_reserve(compskb, IFLA_WIRELESS, event_len);
 572        if (!nla) {
 573                kfree_skb(skb);
 574                kfree_skb(compskb);
 575                return;
 576        }
 577        compat_event = nla_data(nla);
 578
 579        compat_event->len = event_len;
 580        compat_event->cmd = cmd;
 581        if (descr->header_type == IW_HEADER_TYPE_POINT) {
 582                compat_wrqu.length = wrqu->data.length;
 583                compat_wrqu.flags = wrqu->data.flags;
 584                memcpy(&compat_event->pointer,
 585                        ((char *) &compat_wrqu) + IW_EV_COMPAT_POINT_OFF,
 586                        hdr_len - IW_EV_COMPAT_LCP_LEN);
 587                if (extra_len)
 588                        memcpy(((char *) compat_event) + hdr_len,
 589                                extra, extra_len);
 590        } else {
 591                /* extra_len must be zero, so no if (extra) needed */
 592                memcpy(&compat_event->pointer, wrqu,
 593                        hdr_len - IW_EV_COMPAT_LCP_LEN);
 594        }
 595
 596        nlmsg_end(compskb, nlh);
 597
 598        skb_shinfo(skb)->frag_list = compskb;
 599#endif
 600        skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
 601        schedule_work(&wireless_nlevent_work);
 602}
 603EXPORT_SYMBOL(wireless_send_event);
 604
 605
 606
 607/* IW handlers */
 608
 609struct iw_statistics *get_wireless_stats(struct net_device *dev)
 610{
 611#ifdef CONFIG_WIRELESS_EXT
 612        if ((dev->wireless_handlers != NULL) &&
 613           (dev->wireless_handlers->get_wireless_stats != NULL))
 614                return dev->wireless_handlers->get_wireless_stats(dev);
 615#endif
 616
 617#ifdef CONFIG_CFG80211_WEXT
 618        if (dev->ieee80211_ptr &&
 619            dev->ieee80211_ptr->wiphy &&
 620            dev->ieee80211_ptr->wiphy->wext &&
 621            dev->ieee80211_ptr->wiphy->wext->get_wireless_stats)
 622                return dev->ieee80211_ptr->wiphy->wext->get_wireless_stats(dev);
 623#endif
 624
 625        /* not found */
 626        return NULL;
 627}
 628
 629static int iw_handler_get_iwstats(struct net_device *           dev,
 630                                  struct iw_request_info *      info,
 631                                  union iwreq_data *            wrqu,
 632                                  char *                        extra)
 633{
 634        /* Get stats from the driver */
 635        struct iw_statistics *stats;
 636
 637        stats = get_wireless_stats(dev);
 638        if (stats) {
 639                /* Copy statistics to extra */
 640                memcpy(extra, stats, sizeof(struct iw_statistics));
 641                wrqu->data.length = sizeof(struct iw_statistics);
 642
 643                /* Check if we need to clear the updated flag */
 644                if (wrqu->data.flags != 0)
 645                        stats->qual.updated &= ~IW_QUAL_ALL_UPDATED;
 646                return 0;
 647        } else
 648                return -EOPNOTSUPP;
 649}
 650
 651static iw_handler get_handler(struct net_device *dev, unsigned int cmd)
 652{
 653        /* Don't "optimise" the following variable, it will crash */
 654        unsigned int    index;          /* *MUST* be unsigned */
 655        const struct iw_handler_def *handlers = NULL;
 656
 657#ifdef CONFIG_CFG80211_WEXT
 658        if (dev->ieee80211_ptr && dev->ieee80211_ptr->wiphy)
 659                handlers = dev->ieee80211_ptr->wiphy->wext;
 660#endif
 661#ifdef CONFIG_WIRELESS_EXT
 662        if (dev->wireless_handlers)
 663                handlers = dev->wireless_handlers;
 664#endif
 665
 666        if (!handlers)
 667                return NULL;
 668
 669        /* Try as a standard command */
 670        index = IW_IOCTL_IDX(cmd);
 671        if (index < handlers->num_standard)
 672                return handlers->standard[index];
 673
 674#ifdef CONFIG_WEXT_PRIV
 675        /* Try as a private command */
 676        index = cmd - SIOCIWFIRSTPRIV;
 677        if (index < handlers->num_private)
 678                return handlers->private[index];
 679#endif
 680
 681        /* Not found */
 682        return NULL;
 683}
 684
 685static int ioctl_standard_iw_point(struct iw_point *iwp, unsigned int cmd,
 686                                   const struct iw_ioctl_description *descr,
 687                                   iw_handler handler, struct net_device *dev,
 688                                   struct iw_request_info *info)
 689{
 690        int err, extra_size, user_length = 0, essid_compat = 0;
 691        char *extra;
 692
 693        /* Calculate space needed by arguments. Always allocate
 694         * for max space.
 695         */
 696        extra_size = descr->max_tokens * descr->token_size;
 697
 698        /* Check need for ESSID compatibility for WE < 21 */
 699        switch (cmd) {
 700        case SIOCSIWESSID:
 701        case SIOCGIWESSID:
 702        case SIOCSIWNICKN:
 703        case SIOCGIWNICKN:
 704                if (iwp->length == descr->max_tokens + 1)
 705                        essid_compat = 1;
 706                else if (IW_IS_SET(cmd) && (iwp->length != 0)) {
 707                        char essid[IW_ESSID_MAX_SIZE + 1];
 708                        unsigned int len;
 709                        len = iwp->length * descr->token_size;
 710
 711                        if (len > IW_ESSID_MAX_SIZE)
 712                                return -EFAULT;
 713
 714                        err = copy_from_user(essid, iwp->pointer, len);
 715                        if (err)
 716                                return -EFAULT;
 717
 718                        if (essid[iwp->length - 1] == '\0')
 719                                essid_compat = 1;
 720                }
 721                break;
 722        default:
 723                break;
 724        }
 725
 726        iwp->length -= essid_compat;
 727
 728        /* Check what user space is giving us */
 729        if (IW_IS_SET(cmd)) {
 730                /* Check NULL pointer */
 731                if (!iwp->pointer && iwp->length != 0)
 732                        return -EFAULT;
 733                /* Check if number of token fits within bounds */
 734                if (iwp->length > descr->max_tokens)
 735                        return -E2BIG;
 736                if (iwp->length < descr->min_tokens)
 737                        return -EINVAL;
 738        } else {
 739                /* Check NULL pointer */
 740                if (!iwp->pointer)
 741                        return -EFAULT;
 742                /* Save user space buffer size for checking */
 743                user_length = iwp->length;
 744
 745                /* Don't check if user_length > max to allow forward
 746                 * compatibility. The test user_length < min is
 747                 * implied by the test at the end.
 748                 */
 749
 750                /* Support for very large requests */
 751                if ((descr->flags & IW_DESCR_FLAG_NOMAX) &&
 752                    (user_length > descr->max_tokens)) {
 753                        /* Allow userspace to GET more than max so
 754                         * we can support any size GET requests.
 755                         * There is still a limit : -ENOMEM.
 756                         */
 757                        extra_size = user_length * descr->token_size;
 758
 759                        /* Note : user_length is originally a __u16,
 760                         * and token_size is controlled by us,
 761                         * so extra_size won't get negative and
 762                         * won't overflow...
 763                         */
 764                }
 765        }
 766
 767        /* kzalloc() ensures NULL-termination for essid_compat. */
 768        extra = kzalloc(extra_size, GFP_KERNEL);
 769        if (!extra)
 770                return -ENOMEM;
 771
 772        /* If it is a SET, get all the extra data in here */
 773        if (IW_IS_SET(cmd) && (iwp->length != 0)) {
 774                if (copy_from_user(extra, iwp->pointer,
 775                                   iwp->length *
 776                                   descr->token_size)) {
 777                        err = -EFAULT;
 778                        goto out;
 779                }
 780
 781                if (cmd == SIOCSIWENCODEEXT) {
 782                        struct iw_encode_ext *ee = (void *) extra;
 783
 784                        if (iwp->length < sizeof(*ee) + ee->key_len) {
 785                                err = -EFAULT;
 786                                goto out;
 787                        }
 788                }
 789        }
 790
 791        if (IW_IS_GET(cmd) && !(descr->flags & IW_DESCR_FLAG_NOMAX)) {
 792                /*
 793                 * If this is a GET, but not NOMAX, it means that the extra
 794                 * data is not bounded by userspace, but by max_tokens. Thus
 795                 * set the length to max_tokens. This matches the extra data
 796                 * allocation.
 797                 * The driver should fill it with the number of tokens it
 798                 * provided, and it may check iwp->length rather than having
 799                 * knowledge of max_tokens. If the driver doesn't change the
 800                 * iwp->length, this ioctl just copies back max_token tokens
 801                 * filled with zeroes. Hopefully the driver isn't claiming
 802                 * them to be valid data.
 803                 */
 804                iwp->length = descr->max_tokens;
 805        }
 806
 807        err = handler(dev, info, (union iwreq_data *) iwp, extra);
 808
 809        iwp->length += essid_compat;
 810
 811        /* If we have something to return to the user */
 812        if (!err && IW_IS_GET(cmd)) {
 813                /* Check if there is enough buffer up there */
 814                if (user_length < iwp->length) {
 815                        err = -E2BIG;
 816                        goto out;
 817                }
 818
 819                if (copy_to_user(iwp->pointer, extra,
 820                                 iwp->length *
 821                                 descr->token_size)) {
 822                        err = -EFAULT;
 823                        goto out;
 824                }
 825        }
 826
 827        /* Generate an event to notify listeners of the change */
 828        if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
 829            ((err == 0) || (err == -EIWCOMMIT))) {
 830                union iwreq_data *data = (union iwreq_data *) iwp;
 831
 832                if (descr->flags & IW_DESCR_FLAG_RESTRICT)
 833                        /* If the event is restricted, don't
 834                         * export the payload.
 835                         */
 836                        wireless_send_event(dev, cmd, data, NULL);
 837                else
 838                        wireless_send_event(dev, cmd, data, extra);
 839        }
 840
 841out:
 842        kfree(extra);
 843        return err;
 844}
 845
 846/*
 847 * Call the commit handler in the driver
 848 * (if exist and if conditions are right)
 849 *
 850 * Note : our current commit strategy is currently pretty dumb,
 851 * but we will be able to improve on that...
 852 * The goal is to try to agreagate as many changes as possible
 853 * before doing the commit. Drivers that will define a commit handler
 854 * are usually those that need a reset after changing parameters, so
 855 * we want to minimise the number of reset.
 856 * A cool idea is to use a timer : at each "set" command, we re-set the
 857 * timer, when the timer eventually fires, we call the driver.
 858 * Hopefully, more on that later.
 859 *
 860 * Also, I'm waiting to see how many people will complain about the
 861 * netif_running(dev) test. I'm open on that one...
 862 * Hopefully, the driver will remember to do a commit in "open()" ;-)
 863 */
 864int call_commit_handler(struct net_device *dev)
 865{
 866#ifdef CONFIG_WIRELESS_EXT
 867        if ((netif_running(dev)) &&
 868           (dev->wireless_handlers->standard[0] != NULL))
 869                /* Call the commit handler on the driver */
 870                return dev->wireless_handlers->standard[0](dev, NULL,
 871                                                           NULL, NULL);
 872        else
 873                return 0;               /* Command completed successfully */
 874#else
 875        /* cfg80211 has no commit */
 876        return 0;
 877#endif
 878}
 879
 880/*
 881 * Main IOCTl dispatcher.
 882 * Check the type of IOCTL and call the appropriate wrapper...
 883 */
 884static int wireless_process_ioctl(struct net *net, struct ifreq *ifr,
 885                                  unsigned int cmd,
 886                                  struct iw_request_info *info,
 887                                  wext_ioctl_func standard,
 888                                  wext_ioctl_func private)
 889{
 890        struct iwreq *iwr = (struct iwreq *) ifr;
 891        struct net_device *dev;
 892        iw_handler      handler;
 893
 894        /* Permissions are already checked in dev_ioctl() before calling us.
 895         * The copy_to/from_user() of ifr is also dealt with in there */
 896
 897        /* Make sure the device exist */
 898        if ((dev = __dev_get_by_name(net, ifr->ifr_name)) == NULL)
 899                return -ENODEV;
 900
 901        /* A bunch of special cases, then the generic case...
 902         * Note that 'cmd' is already filtered in dev_ioctl() with
 903         * (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) */
 904        if (cmd == SIOCGIWSTATS)
 905                return standard(dev, iwr, cmd, info,
 906                                &iw_handler_get_iwstats);
 907
 908#ifdef CONFIG_WEXT_PRIV
 909        if (cmd == SIOCGIWPRIV && dev->wireless_handlers)
 910                return standard(dev, iwr, cmd, info,
 911                                iw_handler_get_private);
 912#endif
 913
 914        /* Basic check */
 915        if (!netif_device_present(dev))
 916                return -ENODEV;
 917
 918        /* New driver API : try to find the handler */
 919        handler = get_handler(dev, cmd);
 920        if (handler) {
 921                /* Standard and private are not the same */
 922                if (cmd < SIOCIWFIRSTPRIV)
 923                        return standard(dev, iwr, cmd, info, handler);
 924                else if (private)
 925                        return private(dev, iwr, cmd, info, handler);
 926        }
 927        /* Old driver API : call driver ioctl handler */
 928        if (dev->netdev_ops->ndo_do_ioctl)
 929                return dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
 930        return -EOPNOTSUPP;
 931}
 932
 933/* If command is `set a parameter', or `get the encoding parameters',
 934 * check if the user has the right to do it.
 935 */
 936static int wext_permission_check(unsigned int cmd)
 937{
 938        if ((IW_IS_SET(cmd) || cmd == SIOCGIWENCODE ||
 939             cmd == SIOCGIWENCODEEXT) &&
 940            !capable(CAP_NET_ADMIN))
 941                return -EPERM;
 942
 943        return 0;
 944}
 945
 946/* entry point from dev ioctl */
 947static int wext_ioctl_dispatch(struct net *net, struct ifreq *ifr,
 948                               unsigned int cmd, struct iw_request_info *info,
 949                               wext_ioctl_func standard,
 950                               wext_ioctl_func private)
 951{
 952        int ret = wext_permission_check(cmd);
 953
 954        if (ret)
 955                return ret;
 956
 957        dev_load(net, ifr->ifr_name);
 958        rtnl_lock();
 959        ret = wireless_process_ioctl(net, ifr, cmd, info, standard, private);
 960        rtnl_unlock();
 961
 962        return ret;
 963}
 964
 965/*
 966 * Wrapper to call a standard Wireless Extension handler.
 967 * We do various checks and also take care of moving data between
 968 * user space and kernel space.
 969 */
 970static int ioctl_standard_call(struct net_device *      dev,
 971                               struct iwreq             *iwr,
 972                               unsigned int             cmd,
 973                               struct iw_request_info   *info,
 974                               iw_handler               handler)
 975{
 976        const struct iw_ioctl_description *     descr;
 977        int                                     ret = -EINVAL;
 978
 979        /* Get the description of the IOCTL */
 980        if (IW_IOCTL_IDX(cmd) >= standard_ioctl_num)
 981                return -EOPNOTSUPP;
 982        descr = &(standard_ioctl[IW_IOCTL_IDX(cmd)]);
 983
 984        /* Check if we have a pointer to user space data or not */
 985        if (descr->header_type != IW_HEADER_TYPE_POINT) {
 986
 987                /* No extra arguments. Trivial to handle */
 988                ret = handler(dev, info, &(iwr->u), NULL);
 989
 990                /* Generate an event to notify listeners of the change */
 991                if ((descr->flags & IW_DESCR_FLAG_EVENT) &&
 992                   ((ret == 0) || (ret == -EIWCOMMIT)))
 993                        wireless_send_event(dev, cmd, &(iwr->u), NULL);
 994        } else {
 995                ret = ioctl_standard_iw_point(&iwr->u.data, cmd, descr,
 996                                              handler, dev, info);
 997        }
 998
 999        /* Call commit handler if needed and defined */
1000        if (ret == -EIWCOMMIT)
1001                ret = call_commit_handler(dev);
1002
1003        /* Here, we will generate the appropriate event if needed */
1004
1005        return ret;
1006}
1007
1008
1009int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
1010                      void __user *arg)
1011{
1012        struct iw_request_info info = { .cmd = cmd, .flags = 0 };
1013        int ret;
1014
1015        ret = wext_ioctl_dispatch(net, ifr, cmd, &info,
1016                                  ioctl_standard_call,
1017                                  ioctl_private_call);
1018        if (ret >= 0 &&
1019            IW_IS_GET(cmd) &&
1020            copy_to_user(arg, ifr, sizeof(struct iwreq)))
1021                return -EFAULT;
1022
1023        return ret;
1024}
1025
1026#ifdef CONFIG_COMPAT
1027static int compat_standard_call(struct net_device       *dev,
1028                                struct iwreq            *iwr,
1029                                unsigned int            cmd,
1030                                struct iw_request_info  *info,
1031                                iw_handler              handler)
1032{
1033        const struct iw_ioctl_description *descr;
1034        struct compat_iw_point *iwp_compat;
1035        struct iw_point iwp;
1036        int err;
1037
1038        descr = standard_ioctl + IW_IOCTL_IDX(cmd);
1039
1040        if (descr->header_type != IW_HEADER_TYPE_POINT)
1041                return ioctl_standard_call(dev, iwr, cmd, info, handler);
1042
1043        iwp_compat = (struct compat_iw_point *) &iwr->u.data;
1044        iwp.pointer = compat_ptr(iwp_compat->pointer);
1045        iwp.length = iwp_compat->length;
1046        iwp.flags = iwp_compat->flags;
1047
1048        err = ioctl_standard_iw_point(&iwp, cmd, descr, handler, dev, info);
1049
1050        iwp_compat->pointer = ptr_to_compat(iwp.pointer);
1051        iwp_compat->length = iwp.length;
1052        iwp_compat->flags = iwp.flags;
1053
1054        return err;
1055}
1056
1057int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
1058                             unsigned long arg)
1059{
1060        void __user *argp = (void __user *)arg;
1061        struct iw_request_info info;
1062        struct iwreq iwr;
1063        char *colon;
1064        int ret;
1065
1066        if (copy_from_user(&iwr, argp, sizeof(struct iwreq)))
1067                return -EFAULT;
1068
1069        iwr.ifr_name[IFNAMSIZ-1] = 0;
1070        colon = strchr(iwr.ifr_name, ':');
1071        if (colon)
1072                *colon = 0;
1073
1074        info.cmd = cmd;
1075        info.flags = IW_REQUEST_FLAG_COMPAT;
1076
1077        ret = wext_ioctl_dispatch(net, (struct ifreq *) &iwr, cmd, &info,
1078                                  compat_standard_call,
1079                                  compat_private_call);
1080
1081        if (ret >= 0 &&
1082            IW_IS_GET(cmd) &&
1083            copy_to_user(argp, &iwr, sizeof(struct iwreq)))
1084                return -EFAULT;
1085
1086        return ret;
1087}
1088#endif
1089
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.