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         if (connkeys) {
 130                 params->wep_keys = connkeys->params;
 131                 params->wep_tx_key = connkeys->def;
 132         }
 133
 134 #ifdef CONFIG_CFG80211_WEXT
 135         wdev->wext.ibss.chandef = params->chandef;
 136 #endif
 137         err = rdev_join_ibss(rdev, dev, params);
 138         if (err) {
 139                 wdev->connect_keys = NULL;
 140                 return err;
 141         }
 142
 143         memcpy(wdev->ssid, params->ssid, params->ssid_len);
 144         wdev->ssid_len = params->ssid_len;
 145
 146         return 0;
 147 }
 148
 149 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
 150                        struct net_device *dev,
 151                        struct cfg80211_ibss_params *params,
 152                        struct cfg80211_cached_keys *connkeys)
 153 {
 154         struct wireless_dev *wdev = dev->ieee80211_ptr;
 155         int err;
 156
 157         ASSERT_RTNL();
 158
 159         wdev_lock(wdev);
 160         err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
 161         wdev_unlock(wdev);
 162
 163         return err;
 164 }
 165
 166 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 167 {
 168         struct wireless_dev *wdev = dev->ieee80211_ptr;
 169         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 170         int i;
 171
 172         ASSERT_WDEV_LOCK(wdev);
 173
 174         kzfree(wdev->connect_keys);
 175         wdev->connect_keys = NULL;
 176
 177         rdev_set_qos_map(rdev, dev, NULL);
 178
 179         /*
 180          * Delete all the keys ... pairwise keys can't really
 181          * exist any more anyway, but default keys might.
 182          */
 183         if (rdev->ops->del_key)
 184                 for (i = 0; i < 6; i++)
 185                         rdev_del_key(rdev, dev, i, false, NULL);
 186
 187         if (wdev->current_bss) {
 188                 cfg80211_unhold_bss(wdev->current_bss);
 189                 cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
 190         }
 191
 192         wdev->current_bss = NULL;
 193         wdev->ssid_len = 0;
 194         memset(&wdev->chandef, 0, sizeof(wdev->chandef));
 195 #ifdef CONFIG_CFG80211_WEXT
 196         if (!nowext)
 197                 wdev->wext.ibss.ssid_len = 0;
 198 #endif
 199         cfg80211_sched_dfs_chan_update(rdev);
 200 }
 201
 202 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 203 {
 204         struct wireless_dev *wdev = dev->ieee80211_ptr;
 205
 206         wdev_lock(wdev);
 207         __cfg80211_clear_ibss(dev, nowext);
 208         wdev_unlock(wdev);
 209 }
 210
 211 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
 212                           struct net_device *dev, bool nowext)
 213 {
 214         struct wireless_dev *wdev = dev->ieee80211_ptr;
 215         int err;
 216
 217         ASSERT_WDEV_LOCK(wdev);
 218
 219         if (!wdev->ssid_len)
 220                 return -ENOLINK;
 221
 222         err = rdev_leave_ibss(rdev, dev);
 223
 224         if (err)
 225                 return err;
 226
 227         __cfg80211_clear_ibss(dev, nowext);
 228
 229         return 0;
 230 }
 231
 232 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
 233                         struct net_device *dev, bool nowext)
 234 {
 235         struct wireless_dev *wdev = dev->ieee80211_ptr;
 236         int err;
 237
 238         wdev_lock(wdev);
 239         err = __cfg80211_leave_ibss(rdev, dev, nowext);
 240         wdev_unlock(wdev);
 241
 242         return err;
 243 }
 244
 245 #ifdef CONFIG_CFG80211_WEXT
 246 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
 247                             struct wireless_dev *wdev)
 248 {
 249         struct cfg80211_cached_keys *ck = NULL;
 250         enum nl80211_band band;
 251         int i, err;
 252
 253         ASSERT_WDEV_LOCK(wdev);
 254
 255         if (!wdev->wext.ibss.beacon_interval)
 256                 wdev->wext.ibss.beacon_interval = 100;
 257
 258         /* try to find an IBSS channel if none requested ... */
 259         if (!wdev->wext.ibss.chandef.chan) {
 260                 struct ieee80211_channel *new_chan = NULL;
 261
 262                 for (band = 0; band < NUM_NL80211_BANDS; band++) {
 263                         struct ieee80211_supported_band *sband;
 264                         struct ieee80211_channel *chan;
 265
 266                         sband = rdev->wiphy.bands[band];
 267                         if (!sband)
 268                                 continue;
 269
 270                         for (i = 0; i < sband->n_channels; i++) {
 271                                 chan = &sband->channels[i];
 272                                 if (chan->flags & IEEE80211_CHAN_NO_IR)
 273                                         continue;
 274                                 if (chan->flags & IEEE80211_CHAN_DISABLED)
 275                                         continue;
 276                                 new_chan = chan;
 277                                 break;
 278                         }
 279
 280                         if (new_chan)
 281                                 break;
 282                 }
 283
 284                 if (!new_chan)
 285                         return -EINVAL;
 286
 287                 cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
 288                                         NL80211_CHAN_NO_HT);
 289         }
 290
 291         /* don't join -- SSID is not there */
 292         if (!wdev->wext.ibss.ssid_len)
 293                 return 0;
 294
 295         if (!netif_running(wdev->netdev))
 296                 return 0;
 297
 298         if (wdev->wext.keys)
 299                 wdev->wext.keys->def = wdev->wext.default_key;
 300
 301         wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
 302
 303         if (wdev->wext.keys && wdev->wext.keys->def != -1) {
 304                 ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
 305                 if (!ck)
 306                         return -ENOMEM;
 307                 for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++)
 308                         ck->params[i].key = ck->data[i];
 309         }
 310         err = __cfg80211_join_ibss(rdev, wdev->netdev,
 311                                    &wdev->wext.ibss, ck);
 312         if (err)
 313                 kfree(ck);
 314
 315         return err;
 316 }
 317
 318 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
 319                                struct iw_request_info *info,
 320                                struct iw_freq *wextfreq, char *extra)
 321 {
 322         struct wireless_dev *wdev = dev->ieee80211_ptr;
 323         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 324         struct ieee80211_channel *chan = NULL;
 325         int err, freq;
 326
 327         /* call only for ibss! */
 328         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 329                 return -EINVAL;
 330
 331         if (!rdev->ops->join_ibss)
 332                 return -EOPNOTSUPP;
 333
 334         freq = cfg80211_wext_freq(wextfreq);
 335         if (freq < 0)
 336                 return freq;
 337
 338         if (freq) {
 339                 chan = ieee80211_get_channel(wdev->wiphy, freq);
 340                 if (!chan)
 341                         return -EINVAL;
 342                 if (chan->flags & IEEE80211_CHAN_NO_IR ||
 343                     chan->flags & IEEE80211_CHAN_DISABLED)
 344                         return -EINVAL;
 345         }
 346
 347         if (wdev->wext.ibss.chandef.chan == chan)
 348                 return 0;
 349
 350         wdev_lock(wdev);
 351         err = 0;
 352         if (wdev->ssid_len)
 353                 err = __cfg80211_leave_ibss(rdev, dev, true);
 354         wdev_unlock(wdev);
 355
 356         if (err)
 357                 return err;
 358
 359         if (chan) {
 360                 cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
 361                                         NL80211_CHAN_NO_HT);
 362                 wdev->wext.ibss.channel_fixed = true;
 363         } else {
 364                 /* cfg80211_ibss_wext_join will pick one if needed */
 365                 wdev->wext.ibss.channel_fixed = false;
 366         }
 367
 368         wdev_lock(wdev);
 369         err = cfg80211_ibss_wext_join(rdev, wdev);
 370         wdev_unlock(wdev);
 371
 372         return err;
 373 }
 374
 375 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
 376                                struct iw_request_info *info,
 377                                struct iw_freq *freq, char *extra)
 378 {
 379         struct wireless_dev *wdev = dev->ieee80211_ptr;
 380         struct ieee80211_channel *chan = NULL;
 381
 382         /* call only for ibss! */
 383         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 384                 return -EINVAL;
 385
 386         wdev_lock(wdev);
 387         if (wdev->current_bss)
 388                 chan = wdev->current_bss->pub.channel;
 389         else if (wdev->wext.ibss.chandef.chan)
 390                 chan = wdev->wext.ibss.chandef.chan;
 391         wdev_unlock(wdev);
 392
 393         if (chan) {
 394                 freq->m = chan->center_freq;
 395                 freq->e = 6;
 396                 return 0;
 397         }
 398
 399         /* no channel if not joining */
 400         return -EINVAL;
 401 }
 402
 403 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
 404                                 struct iw_request_info *info,
 405                                 struct iw_point *data, char *ssid)
 406 {
 407         struct wireless_dev *wdev = dev->ieee80211_ptr;
 408         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 409         size_t len = data->length;
 410         int err;
 411
 412         /* call only for ibss! */
 413         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 414                 return -EINVAL;
 415
 416         if (!rdev->ops->join_ibss)
 417                 return -EOPNOTSUPP;
 418
 419         wdev_lock(wdev);
 420         err = 0;
 421         if (wdev->ssid_len)
 422                 err = __cfg80211_leave_ibss(rdev, dev, true);
 423         wdev_unlock(wdev);
 424
 425         if (err)
 426                 return err;
 427
 428         /* iwconfig uses nul termination in SSID.. */
 429         if (len > 0 && ssid[len - 1] == '\0')
 430                 len--;
 431
 432         memcpy(wdev->ssid, ssid, len);
 433         wdev->wext.ibss.ssid = wdev->ssid;
 434         wdev->wext.ibss.ssid_len = len;
 435
 436         wdev_lock(wdev);
 437         err = cfg80211_ibss_wext_join(rdev, wdev);
 438         wdev_unlock(wdev);
 439
 440         return err;
 441 }
 442
 443 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
 444                                 struct iw_request_info *info,
 445                                 struct iw_point *data, char *ssid)
 446 {
 447         struct wireless_dev *wdev = dev->ieee80211_ptr;
 448
 449         /* call only for ibss! */
 450         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 451                 return -EINVAL;
 452
 453         data->flags = 0;
 454
 455         wdev_lock(wdev);
 456         if (wdev->ssid_len) {
 457                 data->flags = 1;
 458                 data->length = wdev->ssid_len;
 459                 memcpy(ssid, wdev->ssid, data->length);
 460         } else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
 461                 data->flags = 1;
 462                 data->length = wdev->wext.ibss.ssid_len;
 463                 memcpy(ssid, wdev->wext.ibss.ssid, data->length);
 464         }
 465         wdev_unlock(wdev);
 466
 467         return 0;
 468 }
 469
 470 int cfg80211_ibss_wext_siwap(struct net_device *dev,
 471                              struct iw_request_info *info,
 472                              struct sockaddr *ap_addr, char *extra)
 473 {
 474         struct wireless_dev *wdev = dev->ieee80211_ptr;
 475         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 476         u8 *bssid = ap_addr->sa_data;
 477         int err;
 478
 479         /* call only for ibss! */
 480         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 481                 return -EINVAL;
 482
 483         if (!rdev->ops->join_ibss)
 484                 return -EOPNOTSUPP;
 485
 486         if (ap_addr->sa_family != ARPHRD_ETHER)
 487                 return -EINVAL;
 488
 489         /* automatic mode */
 490         if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
 491                 bssid = NULL;
 492
 493         if (bssid && !is_valid_ether_addr(bssid))
 494                 return -EINVAL;
 495
 496         /* both automatic */
 497         if (!bssid && !wdev->wext.ibss.bssid)
 498                 return 0;
 499
 500         /* fixed already - and no change */
 501         if (wdev->wext.ibss.bssid && bssid &&
 502             ether_addr_equal(bssid, wdev->wext.ibss.bssid))
 503                 return 0;
 504
 505         wdev_lock(wdev);
 506         err = 0;
 507         if (wdev->ssid_len)
 508                 err = __cfg80211_leave_ibss(rdev, dev, true);
 509         wdev_unlock(wdev);
 510
 511         if (err)
 512                 return err;
 513
 514         if (bssid) {
 515                 memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
 516                 wdev->wext.ibss.bssid = wdev->wext.bssid;
 517         } else
 518                 wdev->wext.ibss.bssid = NULL;
 519
 520         wdev_lock(wdev);
 521         err = cfg80211_ibss_wext_join(rdev, wdev);
 522         wdev_unlock(wdev);
 523
 524         return err;
 525 }
 526
 527 int cfg80211_ibss_wext_giwap(struct net_device *dev,
 528                              struct iw_request_info *info,
 529                              struct sockaddr *ap_addr, char *extra)
 530 {
 531         struct wireless_dev *wdev = dev->ieee80211_ptr;
 532
 533         /* call only for ibss! */
 534         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 535                 return -EINVAL;
 536
 537         ap_addr->sa_family = ARPHRD_ETHER;
 538
 539         wdev_lock(wdev);
 540         if (wdev->current_bss)
 541                 memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
 542         else if (wdev->wext.ibss.bssid)
 543                 memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
 544         else
 545                 eth_zero_addr(ap_addr->sa_data);
 546
 547         wdev_unlock(wdev);
 548
 549         return 0;
 550 }
 551 #endif