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  * Copyright (C) 2020-2021 Intel Corporation
   7  */
   8
   9 #include <linux/etherdevice.h>
  10 #include <linux/if_arp.h>
  11 #include <linux/slab.h>
  12 #include <linux/export.h>
  13 #include <net/cfg80211.h>
  14 #include "wext-compat.h"
  15 #include "nl80211.h"
  16 #include "rdev-ops.h"
  17
  18
  19 void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
  20                             struct ieee80211_channel *channel)
  21 {
  22         struct wireless_dev *wdev = dev->ieee80211_ptr;
  23         struct cfg80211_bss *bss;
  24 #ifdef CONFIG_CFG80211_WEXT
  25         union iwreq_data wrqu;
  26 #endif
  27
  28         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
  29                 return;
  30
  31         if (!wdev->ssid_len)
  32                 return;
  33
  34         bss = cfg80211_get_bss(wdev->wiphy, channel, bssid, NULL, 0,
  35                                IEEE80211_BSS_TYPE_IBSS, IEEE80211_PRIVACY_ANY);
  36
  37         if (WARN_ON(!bss))
  38                 return;
  39
  40         if (wdev->current_bss) {
  41                 cfg80211_unhold_bss(wdev->current_bss);
  42                 cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
  43         }
  44
  45         cfg80211_hold_bss(bss_from_pub(bss));
  46         wdev->current_bss = bss_from_pub(bss);
  47
  48         if (!(wdev->wiphy->flags & WIPHY_FLAG_HAS_STATIC_WEP))
  49                 cfg80211_upload_connect_keys(wdev);
  50
  51         nl80211_send_ibss_bssid(wiphy_to_rdev(wdev->wiphy), dev, bssid,
  52                                 GFP_KERNEL);
  53 #ifdef CONFIG_CFG80211_WEXT
  54         memset(&wrqu, 0, sizeof(wrqu));
  55         memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
  56         wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
  57 #endif
  58 }
  59
  60 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
  61                           struct ieee80211_channel *channel, gfp_t gfp)
  62 {
  63         struct wireless_dev *wdev = dev->ieee80211_ptr;
  64         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
  65         struct cfg80211_event *ev;
  66         unsigned long flags;
  67
  68         trace_cfg80211_ibss_joined(dev, bssid, channel);
  69
  70         if (WARN_ON(!channel))
  71                 return;
  72
  73         ev = kzalloc(sizeof(*ev), gfp);
  74         if (!ev)
  75                 return;
  76
  77         ev->type = EVENT_IBSS_JOINED;
  78         memcpy(ev->ij.bssid, bssid, ETH_ALEN);
  79         ev->ij.channel = channel;
  80
  81         spin_lock_irqsave(&wdev->event_lock, flags);
  82         list_add_tail(&ev->list, &wdev->event_list);
  83         spin_unlock_irqrestore(&wdev->event_lock, flags);
  84         queue_work(cfg80211_wq, &rdev->event_work);
  85 }
  86 EXPORT_SYMBOL(cfg80211_ibss_joined);
  87
  88 int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
  89                          struct net_device *dev,
  90                          struct cfg80211_ibss_params *params,
  91                          struct cfg80211_cached_keys *connkeys)
  92 {
  93         struct wireless_dev *wdev = dev->ieee80211_ptr;
  94         int err;
  95
  96         lockdep_assert_held(&rdev->wiphy.mtx);
  97         ASSERT_WDEV_LOCK(wdev);
  98
  99         if (wdev->ssid_len)
 100                 return -EALREADY;
 101
 102         if (!params->basic_rates) {
 103                 /*
 104                 * If no rates were explicitly configured,
 105                 * use the mandatory rate set for 11b or
 106                 * 11a for maximum compatibility.
 107                 */
 108                 struct ieee80211_supported_band *sband;
 109                 enum nl80211_band band;
 110                 u32 flag;
 111                 int j;
 112
 113                 band = params->chandef.chan->band;
 114                 if (band == NL80211_BAND_5GHZ ||
 115                     band == NL80211_BAND_6GHZ)
 116                         flag = IEEE80211_RATE_MANDATORY_A;
 117                 else
 118                         flag = IEEE80211_RATE_MANDATORY_B;
 119
 120                 sband = rdev->wiphy.bands[band];
 121                 for (j = 0; j < sband->n_bitrates; j++) {
 122                         if (sband->bitrates[j].flags & flag)
 123                                 params->basic_rates |= BIT(j);
 124                 }
 125         }
 126
 127         if (WARN_ON(connkeys && connkeys->def < 0))
 128                 return -EINVAL;
 129
 130         if (WARN_ON(wdev->connect_keys))
 131                 kfree_sensitive(wdev->connect_keys);
 132         wdev->connect_keys = connkeys;
 133
 134         wdev->ibss_fixed = params->channel_fixed;
 135         wdev->ibss_dfs_possible = params->userspace_handles_dfs;
 136         wdev->chandef = params->chandef;
 137         if (connkeys) {
 138                 params->wep_keys = connkeys->params;
 139                 params->wep_tx_key = connkeys->def;
 140         }
 141
 142 #ifdef CONFIG_CFG80211_WEXT
 143         wdev->wext.ibss.chandef = params->chandef;
 144 #endif
 145         err = rdev_join_ibss(rdev, dev, params);
 146         if (err) {
 147                 wdev->connect_keys = NULL;
 148                 return err;
 149         }
 150
 151         memcpy(wdev->ssid, params->ssid, params->ssid_len);
 152         wdev->ssid_len = params->ssid_len;
 153
 154         return 0;
 155 }
 156
 157 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 158 {
 159         struct wireless_dev *wdev = dev->ieee80211_ptr;
 160         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 161         int i;
 162
 163         ASSERT_WDEV_LOCK(wdev);
 164
 165         kfree_sensitive(wdev->connect_keys);
 166         wdev->connect_keys = NULL;
 167
 168         rdev_set_qos_map(rdev, dev, NULL);
 169
 170         /*
 171          * Delete all the keys ... pairwise keys can't really
 172          * exist any more anyway, but default keys might.
 173          */
 174         if (rdev->ops->del_key)
 175                 for (i = 0; i < 6; i++)
 176                         rdev_del_key(rdev, dev, i, false, NULL);
 177
 178         if (wdev->current_bss) {
 179                 cfg80211_unhold_bss(wdev->current_bss);
 180                 cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
 181         }
 182
 183         wdev->current_bss = NULL;
 184         wdev->ssid_len = 0;
 185         memset(&wdev->chandef, 0, sizeof(wdev->chandef));
 186 #ifdef CONFIG_CFG80211_WEXT
 187         if (!nowext)
 188                 wdev->wext.ibss.ssid_len = 0;
 189 #endif
 190         cfg80211_sched_dfs_chan_update(rdev);
 191 }
 192
 193 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
 194 {
 195         struct wireless_dev *wdev = dev->ieee80211_ptr;
 196
 197         wdev_lock(wdev);
 198         __cfg80211_clear_ibss(dev, nowext);
 199         wdev_unlock(wdev);
 200 }
 201
 202 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
 203                           struct net_device *dev, bool nowext)
 204 {
 205         struct wireless_dev *wdev = dev->ieee80211_ptr;
 206         int err;
 207
 208         ASSERT_WDEV_LOCK(wdev);
 209
 210         if (!wdev->ssid_len)
 211                 return -ENOLINK;
 212
 213         err = rdev_leave_ibss(rdev, dev);
 214
 215         if (err)
 216                 return err;
 217
 218         wdev->conn_owner_nlportid = 0;
 219         __cfg80211_clear_ibss(dev, nowext);
 220
 221         return 0;
 222 }
 223
 224 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
 225                         struct net_device *dev, bool nowext)
 226 {
 227         struct wireless_dev *wdev = dev->ieee80211_ptr;
 228         int err;
 229
 230         wdev_lock(wdev);
 231         err = __cfg80211_leave_ibss(rdev, dev, nowext);
 232         wdev_unlock(wdev);
 233
 234         return err;
 235 }
 236
 237 #ifdef CONFIG_CFG80211_WEXT
 238 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
 239                             struct wireless_dev *wdev)
 240 {
 241         struct cfg80211_cached_keys *ck = NULL;
 242         enum nl80211_band band;
 243         int i, err;
 244
 245         ASSERT_WDEV_LOCK(wdev);
 246
 247         if (!wdev->wext.ibss.beacon_interval)
 248                 wdev->wext.ibss.beacon_interval = 100;
 249
 250         /* try to find an IBSS channel if none requested ... */
 251         if (!wdev->wext.ibss.chandef.chan) {
 252                 struct ieee80211_channel *new_chan = NULL;
 253
 254                 for (band = 0; band < NUM_NL80211_BANDS; band++) {
 255                         struct ieee80211_supported_band *sband;
 256                         struct ieee80211_channel *chan;
 257
 258                         sband = rdev->wiphy.bands[band];
 259                         if (!sband)
 260                                 continue;
 261
 262                         for (i = 0; i < sband->n_channels; i++) {
 263                                 chan = &sband->channels[i];
 264                                 if (chan->flags & IEEE80211_CHAN_NO_IR)
 265                                         continue;
 266                                 if (chan->flags & IEEE80211_CHAN_DISABLED)
 267                                         continue;
 268                                 new_chan = chan;
 269                                 break;
 270                         }
 271
 272                         if (new_chan)
 273                                 break;
 274                 }
 275
 276                 if (!new_chan)
 277                         return -EINVAL;
 278
 279                 cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
 280                                         NL80211_CHAN_NO_HT);
 281         }
 282
 283         /* don't join -- SSID is not there */
 284         if (!wdev->wext.ibss.ssid_len)
 285                 return 0;
 286
 287         if (!netif_running(wdev->netdev))
 288                 return 0;
 289
 290         if (wdev->wext.keys)
 291                 wdev->wext.keys->def = wdev->wext.default_key;
 292
 293         wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
 294
 295         if (wdev->wext.keys && wdev->wext.keys->def != -1) {
 296                 ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
 297                 if (!ck)
 298                         return -ENOMEM;
 299                 for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++)
 300                         ck->params[i].key = ck->data[i];
 301         }
 302         err = __cfg80211_join_ibss(rdev, wdev->netdev,
 303                                    &wdev->wext.ibss, ck);
 304         if (err)
 305                 kfree(ck);
 306
 307         return err;
 308 }
 309
 310 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
 311                                struct iw_request_info *info,
 312                                struct iw_freq *wextfreq, char *extra)
 313 {
 314         struct wireless_dev *wdev = dev->ieee80211_ptr;
 315         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 316         struct ieee80211_channel *chan = NULL;
 317         int err, freq;
 318
 319         /* call only for ibss! */
 320         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 321                 return -EINVAL;
 322
 323         if (!rdev->ops->join_ibss)
 324                 return -EOPNOTSUPP;
 325
 326         freq = cfg80211_wext_freq(wextfreq);
 327         if (freq < 0)
 328                 return freq;
 329
 330         if (freq) {
 331                 chan = ieee80211_get_channel(wdev->wiphy, freq);
 332                 if (!chan)
 333                         return -EINVAL;
 334                 if (chan->flags & IEEE80211_CHAN_NO_IR ||
 335                     chan->flags & IEEE80211_CHAN_DISABLED)
 336                         return -EINVAL;
 337         }
 338
 339         if (wdev->wext.ibss.chandef.chan == chan)
 340                 return 0;
 341
 342         wdev_lock(wdev);
 343         err = 0;
 344         if (wdev->ssid_len)
 345                 err = __cfg80211_leave_ibss(rdev, dev, true);
 346         wdev_unlock(wdev);
 347
 348         if (err)
 349                 return err;
 350
 351         if (chan) {
 352                 cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
 353                                         NL80211_CHAN_NO_HT);
 354                 wdev->wext.ibss.channel_fixed = true;
 355         } else {
 356                 /* cfg80211_ibss_wext_join will pick one if needed */
 357                 wdev->wext.ibss.channel_fixed = false;
 358         }
 359
 360         wdev_lock(wdev);
 361         err = cfg80211_ibss_wext_join(rdev, wdev);
 362         wdev_unlock(wdev);
 363
 364         return err;
 365 }
 366
 367 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
 368                                struct iw_request_info *info,
 369                                struct iw_freq *freq, char *extra)
 370 {
 371         struct wireless_dev *wdev = dev->ieee80211_ptr;
 372         struct ieee80211_channel *chan = NULL;
 373
 374         /* call only for ibss! */
 375         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 376                 return -EINVAL;
 377
 378         wdev_lock(wdev);
 379         if (wdev->current_bss)
 380                 chan = wdev->current_bss->pub.channel;
 381         else if (wdev->wext.ibss.chandef.chan)
 382                 chan = wdev->wext.ibss.chandef.chan;
 383         wdev_unlock(wdev);
 384
 385         if (chan) {
 386                 freq->m = chan->center_freq;
 387                 freq->e = 6;
 388                 return 0;
 389         }
 390
 391         /* no channel if not joining */
 392         return -EINVAL;
 393 }
 394
 395 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
 396                                 struct iw_request_info *info,
 397                                 struct iw_point *data, char *ssid)
 398 {
 399         struct wireless_dev *wdev = dev->ieee80211_ptr;
 400         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 401         size_t len = data->length;
 402         int err;
 403
 404         /* call only for ibss! */
 405         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 406                 return -EINVAL;
 407
 408         if (!rdev->ops->join_ibss)
 409                 return -EOPNOTSUPP;
 410
 411         wdev_lock(wdev);
 412         err = 0;
 413         if (wdev->ssid_len)
 414                 err = __cfg80211_leave_ibss(rdev, dev, true);
 415         wdev_unlock(wdev);
 416
 417         if (err)
 418                 return err;
 419
 420         /* iwconfig uses nul termination in SSID.. */
 421         if (len > 0 && ssid[len - 1] == '\0')
 422                 len--;
 423
 424         memcpy(wdev->ssid, ssid, len);
 425         wdev->wext.ibss.ssid = wdev->ssid;
 426         wdev->wext.ibss.ssid_len = len;
 427
 428         wdev_lock(wdev);
 429         err = cfg80211_ibss_wext_join(rdev, wdev);
 430         wdev_unlock(wdev);
 431
 432         return err;
 433 }
 434
 435 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
 436                                 struct iw_request_info *info,
 437                                 struct iw_point *data, char *ssid)
 438 {
 439         struct wireless_dev *wdev = dev->ieee80211_ptr;
 440
 441         /* call only for ibss! */
 442         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 443                 return -EINVAL;
 444
 445         data->flags = 0;
 446
 447         wdev_lock(wdev);
 448         if (wdev->ssid_len) {
 449                 data->flags = 1;
 450                 data->length = wdev->ssid_len;
 451                 memcpy(ssid, wdev->ssid, data->length);
 452         } else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
 453                 data->flags = 1;
 454                 data->length = wdev->wext.ibss.ssid_len;
 455                 memcpy(ssid, wdev->wext.ibss.ssid, data->length);
 456         }
 457         wdev_unlock(wdev);
 458
 459         return 0;
 460 }
 461
 462 int cfg80211_ibss_wext_siwap(struct net_device *dev,
 463                              struct iw_request_info *info,
 464                              struct sockaddr *ap_addr, char *extra)
 465 {
 466         struct wireless_dev *wdev = dev->ieee80211_ptr;
 467         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 468         u8 *bssid = ap_addr->sa_data;
 469         int err;
 470
 471         /* call only for ibss! */
 472         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 473                 return -EINVAL;
 474
 475         if (!rdev->ops->join_ibss)
 476                 return -EOPNOTSUPP;
 477
 478         if (ap_addr->sa_family != ARPHRD_ETHER)
 479                 return -EINVAL;
 480
 481         /* automatic mode */
 482         if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
 483                 bssid = NULL;
 484
 485         if (bssid && !is_valid_ether_addr(bssid))
 486                 return -EINVAL;
 487
 488         /* both automatic */
 489         if (!bssid && !wdev->wext.ibss.bssid)
 490                 return 0;
 491
 492         /* fixed already - and no change */
 493         if (wdev->wext.ibss.bssid && bssid &&
 494             ether_addr_equal(bssid, wdev->wext.ibss.bssid))
 495                 return 0;
 496
 497         wdev_lock(wdev);
 498         err = 0;
 499         if (wdev->ssid_len)
 500                 err = __cfg80211_leave_ibss(rdev, dev, true);
 501         wdev_unlock(wdev);
 502
 503         if (err)
 504                 return err;
 505
 506         if (bssid) {
 507                 memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
 508                 wdev->wext.ibss.bssid = wdev->wext.bssid;
 509         } else
 510                 wdev->wext.ibss.bssid = NULL;
 511
 512         wdev_lock(wdev);
 513         err = cfg80211_ibss_wext_join(rdev, wdev);
 514         wdev_unlock(wdev);
 515
 516         return err;
 517 }
 518
 519 int cfg80211_ibss_wext_giwap(struct net_device *dev,
 520                              struct iw_request_info *info,
 521                              struct sockaddr *ap_addr, char *extra)
 522 {
 523         struct wireless_dev *wdev = dev->ieee80211_ptr;
 524
 525         /* call only for ibss! */
 526         if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
 527                 return -EINVAL;
 528
 529         ap_addr->sa_family = ARPHRD_ETHER;
 530
 531         wdev_lock(wdev);
 532         if (wdev->current_bss)
 533                 memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
 534         else if (wdev->wext.ibss.bssid)
 535                 memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
 536         else
 537                 eth_zero_addr(ap_addr->sa_data);
 538
 539         wdev_unlock(wdev);
 540
 541         return 0;
 542 }
 543 #endif