net/wireless/ibss.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Some IBSS support code for cfg80211.
   4  *
   5  * Copyright 2009       Johannes Berg <johannes@sipsolutions.net>
   6  */
   7
   8 #include <linux/etherdevice.h>
   9 #include <linux/if_arp.h>
  10 #include <linux/slab.h>
  11 #include <linux/export.h>
  12 #include <net/cfg80211.h>
  13 #include "wext-compat.h"
  14 #include "nl80211.h"
  15 #include "rdev-ops.h"
  16
  17
  18 void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
  19                             struct ieee80211_channel *channel)
  20 {
  21         struct wireless_dev *wdev = dev->ieee80211_ptr;
  22         struct cfg80211_bss *bss;
  23 #ifdef CONFIG_CFG80211_WEXT
  24         union iwreq_data wrqu;
  25 #endif
  26
  27         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
  28                 return;
  29
  30         if (!wdev->ssid_len)
  31                 return;
  32
  33         bss = cfg80211_get_bss(wdev->wiphy, channel, bssid, NULL, 0,
  34                                IEEE80211_BSS_TYPE_IBSS, IEEE80211_PRIVACY_ANY);
  35
  36         if (WARN_ON(!bss))
  37                 return;
  38
  39         if (wdev->current_bss) {
  40                 cfg80211_unhold_bss(wdev->current_bss);
  41                 cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
  42         }
  43
  44         cfg80211_hold_bss(bss_from_pub(bss));
  45         wdev->current_bss = bss_from_pub(bss);
  46
  47         if (!(wdev->wiphy->flags & WIPHY_FLAG_HAS_STATIC_WEP))
  48                 cfg80211_upload_connect_keys(wdev);
  49
  50         nl80211_send_ibss_bssid(wiphy_to_rdev(wdev->wiphy), dev, bssid,
  51                                 GFP_KERNEL);
  52 #ifdef CONFIG_CFG80211_WEXT
  53         memset(&wrqu, 0, sizeof(wrqu));
  54         memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
  55         wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
  56 #endif
  57 }
  58
  59 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
  60                           struct ieee80211_channel *channel, gfp_t gfp)
  61 {
  62         struct wireless_dev *wdev = dev->ieee80211_ptr;
  63         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
  64         struct cfg80211_event *ev;
  65         unsigned long flags;
  66
  67         trace_cfg80211_ibss_joined(dev, bssid, channel);
  68
  69         if (WARN_ON(!channel))
  70                 return;
  71
  72         ev = kzalloc(sizeof(*ev), gfp);
  73         if (!ev)
  74                 return;
  75
  76         ev->type = EVENT_IBSS_JOINED;
  77         memcpy(ev->ij.bssid, bssid, ETH_ALEN);
  78         ev->ij.channel = channel;
  79
  80         spin_lock_irqsave(&wdev->event_lock, flags);
  81         list_add_tail(&ev->list, &wdev->event_list);
  82         spin_unlock_irqrestore(&wdev->event_lock, flags);
  83         queue_work(cfg80211_wq, &rdev->event_work);
  84 }
  85 EXPORT_SYMBOL(cfg80211_ibss_joined);
  86
  87 static int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
  88                                 struct net_device *dev,
  89                                 struct cfg80211_ibss_params *params,
  90                                 struct cfg80211_cached_keys *connkeys)
  91 {
  92         struct wireless_dev *wdev = dev->ieee80211_ptr;
  93         int err;
  94
  95         ASSERT_WDEV_LOCK(wdev);
  96
  97         if (wdev->ssid_len)
  98                 return -EALREADY;
  99
 100         if (!params->basic_rates) {
 101                 /*
 102                 * If no rates were explicitly configured,
 103                 * use the mandatory rate set for 11b or
 104                 * 11a for maximum compatibility.
 105                 */
 106                 struct ieee80211_supported_band *sband =
 107                         rdev->wiphy.bands[params->chandef.chan->band];
 108                 int j;
 109                 u32 flag = params->chandef.chan->band == NL80211_BAND_5GHZ ?
 110                         IEEE80211_RATE_MANDATORY_A :
 111                         IEEE80211_RATE_MANDATORY_B;
 112
 113                 for (j = 0; j < sband->n_bitrates; j++) {
 114                         if (sband->bitrates[j].flags & flag)
 115                                 params->basic_rates |= BIT(j);
 116                 }
 117         }
 118
 119         if (WARN_ON(connkeys && connkeys->def < 0))
 120                 return -EINVAL;
 121
 122         if (WARN_ON(wdev->connect_keys))
 123                 kzfree(wdev->connect_keys);
 124         wdev->connect_keys = connkeys;
 125
 126         wdev->ibss_fixed = params->channel_fixed;
 127         wdev->ibss_dfs_possible = params->userspace_handles_dfs;
 128         wdev->chandef = params->chandef;
 129 #ifdef CONFIG_CFG80211_WEXT
 130         wdev->wext.ibss.chandef = params->chandef;
 131 #endif
 132         err = rdev_join_ibss(rdev, dev, params);
 133         if (err) {
 134                 wdev->connect_keys = NULL;
 135                 return err;
 136         }
 137
 138         memcpy(wdev->ssid, params->ssid, params->ssid_len);
 139         wdev->ssid_len = params->ssid_len;
 140
 141         return 0;
 142 }
 143
 144 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 145                        struct net_device *dev,
 146                        struct cfg80211_ibss_params *params,
 147                        struct cfg80211_cached_keys *connkeys)
 148 {
 149         struct wireless_dev *wdev = dev->ieee80211_ptr;
 150         int err;
 151
 152         ASSERT_RTNL();
 153
 154         wdev_lock(wdev);
 155         err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
 156         wdev_unlock(wdev);
 157
 158         return err;
 159 }
 160
 161 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 162 {
 163         struct wireless_dev *wdev = dev->ieee80211_ptr;
 164         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 165         int i;
 166
 167         ASSERT_WDEV_LOCK(wdev);
 168
 169         kzfree(wdev->connect_keys);
 170         wdev->connect_keys = NULL;
 171
 172         rdev_set_qos_map(rdev, dev, NULL);
 173
 174         /*
 175          * Delete all the keys ... pairwise keys can't really
 176          * exist any more anyway, but default keys might.
 177          */
 178         if (rdev->ops->del_key)
 179                 for (i = 0; i < 6; i++)
 180                         rdev_del_key(rdev, dev, i, false, NULL);
 181
 182         if (wdev->current_bss) {
 183                 cfg80211_unhold_bss(wdev->current_bss);
 184                 cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
 185         }
 186
 187         wdev->current_bss = NULL;
 188         wdev->ssid_len = 0;
 189         memset(&wdev->chandef, 0, sizeof(wdev->chandef));
 190 #ifdef CONFIG_CFG80211_WEXT
 191         if (!nowext)
 192                 wdev->wext.ibss.ssid_len = 0;
 193 #endif
 194         cfg80211_sched_dfs_chan_update(rdev);
 195 }
 196
 197 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 198 {
 199         struct wireless_dev *wdev = dev->ieee80211_ptr;
 200
 201         wdev_lock(wdev);
 202         __cfg80211_clear_ibss(dev, nowext);
 203         wdev_unlock(wdev);
 204 }
 205
 206 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
 207                           struct net_device *dev, bool nowext)
 208 {
 209         struct wireless_dev *wdev = dev->ieee80211_ptr;
 210         int err;
 211
 212         ASSERT_WDEV_LOCK(wdev);
 213
 214         if (!wdev->ssid_len)
 215                 return -ENOLINK;
 216
 217         err = rdev_leave_ibss(rdev, dev);
 218
 219         if (err)
 220                 return err;
 221
 222         __cfg80211_clear_ibss(dev, nowext);
 223
 224         return 0;
 225 }
 226
 227 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
 228                         struct net_device *dev, bool nowext)
 229 {
 230         struct wireless_dev *wdev = dev->ieee80211_ptr;
 231         int err;
 232
 233         wdev_lock(wdev);
 234         err = __cfg80211_leave_ibss(rdev, dev, nowext);
 235         wdev_unlock(wdev);
 236
 237         return err;
 238 }
 239
 240 #ifdef CONFIG_CFG80211_WEXT
 241 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
 242                             struct wireless_dev *wdev)
 243 {
 244         struct cfg80211_cached_keys *ck = NULL;
 245         enum nl80211_band band;
 246         int i, err;
 247
 248         ASSERT_WDEV_LOCK(wdev);
 249
 250         if (!wdev->wext.ibss.beacon_interval)
 251                 wdev->wext.ibss.beacon_interval = 100;
 252
 253         /* try to find an IBSS channel if none requested ... */
 254         if (!wdev->wext.ibss.chandef.chan) {
 255                 struct ieee80211_channel *new_chan = NULL;
 256
 257                 for (band = 0; band < NUM_NL80211_BANDS; band++) {
 258                         struct ieee80211_supported_band *sband;
 259                         struct ieee80211_channel *chan;
 260
 261                         sband = rdev->wiphy.bands[band];
 262                         if (!sband)
 263                                 continue;
 264
 265                         for (i = 0; i < sband->n_channels; i++) {
 266                                 chan = &sband->channels[i];
 267                                 if (chan->flags & IEEE80211_CHAN_NO_IR)
 268                                         continue;
 269                                 if (chan->flags & IEEE80211_CHAN_DISABLED)
 270                                         continue;
 271                                 new_chan = chan;
 272                                 break;
 273                         }
 274
 275                         if (new_chan)
 276                                 break;
 277                 }
 278
 279                 if (!new_chan)
 280                         return -EINVAL;
 281
 282                 cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
 283                                         NL80211_CHAN_NO_HT);
 284         }
 285
 286         /* don't join -- SSID is not there */
 287         if (!wdev->wext.ibss.ssid_len)
 288                 return 0;
 289
 290         if (!netif_running(wdev->netdev))
 291                 return 0;
 292
 293         if (wdev->wext.keys)
 294                 wdev->wext.keys->def = wdev->wext.default_key;
 295
 296         wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
 297
 298         if (wdev->wext.keys && wdev->wext.keys->def != -1) {
 299                 ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
 300                 if (!ck)
 301                         return -ENOMEM;
 302                 for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++)
 303                         ck->params[i].key = ck->data[i];
 304         }
 305         err = __cfg80211_join_ibss(rdev, wdev->netdev,
 306                                    &wdev->wext.ibss, ck);
 307         if (err)
 308                 kfree(ck);
 309
 310         return err;
 311 }
 312
 313 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
 314                                struct iw_request_info *info,
 315                                struct iw_freq *wextfreq, char *extra)
 316 {
 317         struct wireless_dev *wdev = dev->ieee80211_ptr;
 318         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 319         struct ieee80211_channel *chan = NULL;
 320         int err, freq;
 321
 322         /* call only for ibss! */
 323         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 324                 return -EINVAL;
 325
 326         if (!rdev->ops->join_ibss)
 327                 return -EOPNOTSUPP;
 328
 329         freq = cfg80211_wext_freq(wextfreq);
 330         if (freq < 0)
 331                 return freq;
 332
 333         if (freq) {
 334                 chan = ieee80211_get_channel(wdev->wiphy, freq);
 335                 if (!chan)
 336                         return -EINVAL;
 337                 if (chan->flags & IEEE80211_CHAN_NO_IR ||
 338                     chan->flags & IEEE80211_CHAN_DISABLED)
 339                         return -EINVAL;
 340         }
 341
 342         if (wdev->wext.ibss.chandef.chan == chan)
 343                 return 0;
 344
 345         wdev_lock(wdev);
 346         err = 0;
 347         if (wdev->ssid_len)
 348                 err = __cfg80211_leave_ibss(rdev, dev, true);
 349         wdev_unlock(wdev);
 350
 351         if (err)
 352                 return err;
 353
 354         if (chan) {
 355                 cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
 356                                         NL80211_CHAN_NO_HT);
 357                 wdev->wext.ibss.channel_fixed = true;
 358         } else {
 359                 /* cfg80211_ibss_wext_join will pick one if needed */
 360                 wdev->wext.ibss.channel_fixed = false;
 361         }
 362
 363         wdev_lock(wdev);
 364         err = cfg80211_ibss_wext_join(rdev, wdev);
 365         wdev_unlock(wdev);
 366
 367         return err;
 368 }
 369
 370 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
 371                                struct iw_request_info *info,
 372                                struct iw_freq *freq, char *extra)
 373 {
 374         struct wireless_dev *wdev = dev->ieee80211_ptr;
 375         struct ieee80211_channel *chan = NULL;
 376
 377         /* call only for ibss! */
 378         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 379                 return -EINVAL;
 380
 381         wdev_lock(wdev);
 382         if (wdev->current_bss)
 383                 chan = wdev->current_bss->pub.channel;
 384         else if (wdev->wext.ibss.chandef.chan)
 385                 chan = wdev->wext.ibss.chandef.chan;
 386         wdev_unlock(wdev);
 387
 388         if (chan) {
 389                 freq->m = chan->center_freq;
 390                 freq->e = 6;
 391                 return 0;
 392         }
 393
 394         /* no channel if not joining */
 395         return -EINVAL;
 396 }
 397
 398 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
 399                                 struct iw_request_info *info,
 400                                 struct iw_point *data, char *ssid)
 401 {
 402         struct wireless_dev *wdev = dev->ieee80211_ptr;
 403         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 404         size_t len = data->length;
 405         int err;
 406
 407         /* call only for ibss! */
 408         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 409                 return -EINVAL;
 410
 411         if (!rdev->ops->join_ibss)
 412                 return -EOPNOTSUPP;
 413
 414         wdev_lock(wdev);
 415         err = 0;
 416         if (wdev->ssid_len)
 417                 err = __cfg80211_leave_ibss(rdev, dev, true);
 418         wdev_unlock(wdev);
 419
 420         if (err)
 421                 return err;
 422
 423         /* iwconfig uses nul termination in SSID.. */
 424         if (len > 0 && ssid[len - 1] == '\0')
 425                 len--;
 426
 427         memcpy(wdev->ssid, ssid, len);
 428         wdev->wext.ibss.ssid = wdev->ssid;
 429         wdev->wext.ibss.ssid_len = len;
 430
 431         wdev_lock(wdev);
 432         err = cfg80211_ibss_wext_join(rdev, wdev);
 433         wdev_unlock(wdev);
 434
 435         return err;
 436 }
 437
 438 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
 439                                 struct iw_request_info *info,
 440                                 struct iw_point *data, char *ssid)
 441 {
 442         struct wireless_dev *wdev = dev->ieee80211_ptr;
 443
 444         /* call only for ibss! */
 445         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 446                 return -EINVAL;
 447
 448         data->flags = 0;
 449
 450         wdev_lock(wdev);
 451         if (wdev->ssid_len) {
 452                 data->flags = 1;
 453                 data->length = wdev->ssid_len;
 454                 memcpy(ssid, wdev->ssid, data->length);
 455         } else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
 456                 data->flags = 1;
 457                 data->length = wdev->wext.ibss.ssid_len;
 458                 memcpy(ssid, wdev->wext.ibss.ssid, data->length);
 459         }
 460         wdev_unlock(wdev);
 461
 462         return 0;
 463 }
 464
 465 int cfg80211_ibss_wext_siwap(struct net_device *dev,
 466                              struct iw_request_info *info,
 467                              struct sockaddr *ap_addr, char *extra)
 468 {
 469         struct wireless_dev *wdev = dev->ieee80211_ptr;
 470         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 471         u8 *bssid = ap_addr->sa_data;
 472         int err;
 473
 474         /* call only for ibss! */
 475         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 476                 return -EINVAL;
 477
 478         if (!rdev->ops->join_ibss)
 479                 return -EOPNOTSUPP;
 480
 481         if (ap_addr->sa_family != ARPHRD_ETHER)
 482                 return -EINVAL;
 483
 484         /* automatic mode */
 485         if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
 486                 bssid = NULL;
 487
 488         if (bssid && !is_valid_ether_addr(bssid))
 489                 return -EINVAL;
 490
 491         /* both automatic */
 492         if (!bssid && !wdev->wext.ibss.bssid)
 493                 return 0;
 494
 495         /* fixed already - and no change */
 496         if (wdev->wext.ibss.bssid && bssid &&
 497             ether_addr_equal(bssid, wdev->wext.ibss.bssid))
 498                 return 0;
 499
 500         wdev_lock(wdev);
 501         err = 0;
 502         if (wdev->ssid_len)
 503                 err = __cfg80211_leave_ibss(rdev, dev, true);
 504         wdev_unlock(wdev);
 505
 506         if (err)
 507                 return err;
 508
 509         if (bssid) {
 510                 memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
 511                 wdev->wext.ibss.bssid = wdev->wext.bssid;
 512         } else
 513                 wdev->wext.ibss.bssid = NULL;
 514
 515         wdev_lock(wdev);
 516         err = cfg80211_ibss_wext_join(rdev, wdev);
 517         wdev_unlock(wdev);
 518
 519         return err;
 520 }
 521
 522 int cfg80211_ibss_wext_giwap(struct net_device *dev,
 523                              struct iw_request_info *info,
 524                              struct sockaddr *ap_addr, char *extra)
 525 {
 526         struct wireless_dev *wdev = dev->ieee80211_ptr;
 527
 528         /* call only for ibss! */
 529         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 530                 return -EINVAL;
 531
 532         ap_addr->sa_family = ARPHRD_ETHER;
 533
 534         wdev_lock(wdev);
 535         if (wdev->current_bss)
 536                 memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
 537         else if (wdev->wext.ibss.bssid)
 538                 memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
 539         else
 540                 eth_zero_addr(ap_addr->sa_data);
 541
 542         wdev_unlock(wdev);
 543
 544         return 0;
 545 }
 546 #endif