net/wireless/chan.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * This file contains helper code to handle channel
   4  * settings and keeping track of what is possible at
   5  * any point in time.
   6  *
   7  * Copyright 2009       Johannes Berg <johannes@sipsolutions.net>
   8  * Copyright 2013-2014  Intel Mobile Communications GmbH
   9  * Copyright 2018       Intel Corporation
  10  */
  11
  12 #include <linux/export.h>
  13 #include <net/cfg80211.h>
  14 #include "core.h"
  15 #include "rdev-ops.h"
  16
  17 void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
  18                              struct ieee80211_channel *chan,
  19                              enum nl80211_channel_type chan_type)
  20 {
  21         if (WARN_ON(!chan))
  22                 return;
  23
  24         chandef->chan = chan;
  25         chandef->center_freq2 = 0;
  26
  27         switch (chan_type) {
  28         case NL80211_CHAN_NO_HT:
  29                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
  30                 chandef->center_freq1 = chan->center_freq;
  31                 break;
  32         case NL80211_CHAN_HT20:
  33                 chandef->width = NL80211_CHAN_WIDTH_20;
  34                 chandef->center_freq1 = chan->center_freq;
  35                 break;
  36         case NL80211_CHAN_HT40PLUS:
  37                 chandef->width = NL80211_CHAN_WIDTH_40;
  38                 chandef->center_freq1 = chan->center_freq + 10;
  39                 break;
  40         case NL80211_CHAN_HT40MINUS:
  41                 chandef->width = NL80211_CHAN_WIDTH_40;
  42                 chandef->center_freq1 = chan->center_freq - 10;
  43                 break;
  44         default:
  45                 WARN_ON(1);
  46         }
  47 }
  48 EXPORT_SYMBOL(cfg80211_chandef_create);
  49
  50 bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
  51 {
  52         u32 control_freq;
  53
  54         if (!chandef->chan)
  55                 return false;
  56
  57         control_freq = chandef->chan->center_freq;
  58
  59         switch (chandef->width) {
  60         case NL80211_CHAN_WIDTH_5:
  61         case NL80211_CHAN_WIDTH_10:
  62         case NL80211_CHAN_WIDTH_20:
  63         case NL80211_CHAN_WIDTH_20_NOHT:
  64                 if (chandef->center_freq1 != control_freq)
  65                         return false;
  66                 if (chandef->center_freq2)
  67                         return false;
  68                 break;
  69         case NL80211_CHAN_WIDTH_40:
  70                 if (chandef->center_freq1 != control_freq + 10 &&
  71                     chandef->center_freq1 != control_freq - 10)
  72                         return false;
  73                 if (chandef->center_freq2)
  74                         return false;
  75                 break;
  76         case NL80211_CHAN_WIDTH_80P80:
  77                 if (chandef->center_freq1 != control_freq + 30 &&
  78                     chandef->center_freq1 != control_freq + 10 &&
  79                     chandef->center_freq1 != control_freq - 10 &&
  80                     chandef->center_freq1 != control_freq - 30)
  81                         return false;
  82                 if (!chandef->center_freq2)
  83                         return false;
  84                 /* adjacent is not allowed -- that's a 160 MHz channel */
  85                 if (chandef->center_freq1 - chandef->center_freq2 == 80 ||
  86                     chandef->center_freq2 - chandef->center_freq1 == 80)
  87                         return false;
  88                 break;
  89         case NL80211_CHAN_WIDTH_80:
  90                 if (chandef->center_freq1 != control_freq + 30 &&
  91                     chandef->center_freq1 != control_freq + 10 &&
  92                     chandef->center_freq1 != control_freq - 10 &&
  93                     chandef->center_freq1 != control_freq - 30)
  94                         return false;
  95                 if (chandef->center_freq2)
  96                         return false;
  97                 break;
  98         case NL80211_CHAN_WIDTH_160:
  99                 if (chandef->center_freq1 != control_freq + 70 &&
 100                     chandef->center_freq1 != control_freq + 50 &&
 101                     chandef->center_freq1 != control_freq + 30 &&
 102                     chandef->center_freq1 != control_freq + 10 &&
 103                     chandef->center_freq1 != control_freq - 10 &&
 104                     chandef->center_freq1 != control_freq - 30 &&
 105                     chandef->center_freq1 != control_freq - 50 &&
 106                     chandef->center_freq1 != control_freq - 70)
 107                         return false;
 108                 if (chandef->center_freq2)
 109                         return false;
 110                 break;
 111         default:
 112                 return false;
 113         }
 114
 115         return true;
 116 }
 117 EXPORT_SYMBOL(cfg80211_chandef_valid);
 118
 119 static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
 120                                   u32 *pri40, u32 *pri80)
 121 {
 122         int tmp;
 123
 124         switch (c->width) {
 125         case NL80211_CHAN_WIDTH_40:
 126                 *pri40 = c->center_freq1;
 127                 *pri80 = 0;
 128                 break;
 129         case NL80211_CHAN_WIDTH_80:
 130         case NL80211_CHAN_WIDTH_80P80:
 131                 *pri80 = c->center_freq1;
 132                 /* n_P20 */
 133                 tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
 134                 /* n_P40 */
 135                 tmp /= 2;
 136                 /* freq_P40 */
 137                 *pri40 = c->center_freq1 - 20 + 40 * tmp;
 138                 break;
 139         case NL80211_CHAN_WIDTH_160:
 140                 /* n_P20 */
 141                 tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
 142                 /* n_P40 */
 143                 tmp /= 2;
 144                 /* freq_P40 */
 145                 *pri40 = c->center_freq1 - 60 + 40 * tmp;
 146                 /* n_P80 */
 147                 tmp /= 2;
 148                 *pri80 = c->center_freq1 - 40 + 80 * tmp;
 149                 break;
 150         default:
 151                 WARN_ON_ONCE(1);
 152         }
 153 }
 154
 155 static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
 156 {
 157         int width;
 158
 159         switch (c->width) {
 160         case NL80211_CHAN_WIDTH_5:
 161                 width = 5;
 162                 break;
 163         case NL80211_CHAN_WIDTH_10:
 164                 width = 10;
 165                 break;
 166         case NL80211_CHAN_WIDTH_20:
 167         case NL80211_CHAN_WIDTH_20_NOHT:
 168                 width = 20;
 169                 break;
 170         case NL80211_CHAN_WIDTH_40:
 171                 width = 40;
 172                 break;
 173         case NL80211_CHAN_WIDTH_80P80:
 174         case NL80211_CHAN_WIDTH_80:
 175                 width = 80;
 176                 break;
 177         case NL80211_CHAN_WIDTH_160:
 178                 width = 160;
 179                 break;
 180         default:
 181                 WARN_ON_ONCE(1);
 182                 return -1;
 183         }
 184         return width;
 185 }
 186
 187 const struct cfg80211_chan_def *
 188 cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
 189                             const struct cfg80211_chan_def *c2)
 190 {
 191         u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;
 192
 193         /* If they are identical, return */
 194         if (cfg80211_chandef_identical(c1, c2))
 195                 return c1;
 196
 197         /* otherwise, must have same control channel */
 198         if (c1->chan != c2->chan)
 199                 return NULL;
 200
 201         /*
 202          * If they have the same width, but aren't identical,
 203          * then they can't be compatible.
 204          */
 205         if (c1->width == c2->width)
 206                 return NULL;
 207
 208         /*
 209          * can't be compatible if one of them is 5 or 10 MHz,
 210          * but they don't have the same width.
 211          */
 212         if (c1->width == NL80211_CHAN_WIDTH_5 ||
 213             c1->width == NL80211_CHAN_WIDTH_10 ||
 214             c2->width == NL80211_CHAN_WIDTH_5 ||
 215             c2->width == NL80211_CHAN_WIDTH_10)
 216                 return NULL;
 217
 218         if (c1->width == NL80211_CHAN_WIDTH_20_NOHT ||
 219             c1->width == NL80211_CHAN_WIDTH_20)
 220                 return c2;
 221
 222         if (c2->width == NL80211_CHAN_WIDTH_20_NOHT ||
 223             c2->width == NL80211_CHAN_WIDTH_20)
 224                 return c1;
 225
 226         chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
 227         chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);
 228
 229         if (c1_pri40 != c2_pri40)
 230                 return NULL;
 231
 232         WARN_ON(!c1_pri80 && !c2_pri80);
 233         if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
 234                 return NULL;
 235
 236         if (c1->width > c2->width)
 237                 return c1;
 238         return c2;
 239 }
 240 EXPORT_SYMBOL(cfg80211_chandef_compatible);
 241
 242 static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
 243                                          u32 bandwidth,
 244                                          enum nl80211_dfs_state dfs_state)
 245 {
 246         struct ieee80211_channel *c;
 247         u32 freq;
 248
 249         for (freq = center_freq - bandwidth/2 + 10;
 250              freq <= center_freq + bandwidth/2 - 10;
 251              freq += 20) {
 252                 c = ieee80211_get_channel(wiphy, freq);
 253                 if (!c || !(c->flags & IEEE80211_CHAN_RADAR))
 254                         continue;
 255
 256                 c->dfs_state = dfs_state;
 257                 c->dfs_state_entered = jiffies;
 258         }
 259 }
 260
 261 void cfg80211_set_dfs_state(struct wiphy *wiphy,
 262                             const struct cfg80211_chan_def *chandef,
 263                             enum nl80211_dfs_state dfs_state)
 264 {
 265         int width;
 266
 267         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 268                 return;
 269
 270         width = cfg80211_chandef_get_width(chandef);
 271         if (width < 0)
 272                 return;
 273
 274         cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
 275                                      width, dfs_state);
 276
 277         if (!chandef->center_freq2)
 278                 return;
 279         cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
 280                                      width, dfs_state);
 281 }
 282
 283 static u32 cfg80211_get_start_freq(u32 center_freq,
 284                                    u32 bandwidth)
 285 {
 286         u32 start_freq;
 287
 288         if (bandwidth <= 20)
 289                 start_freq = center_freq;
 290         else
 291                 start_freq = center_freq - bandwidth/2 + 10;
 292
 293         return start_freq;
 294 }
 295
 296 static u32 cfg80211_get_end_freq(u32 center_freq,
 297                                  u32 bandwidth)
 298 {
 299         u32 end_freq;
 300
 301         if (bandwidth <= 20)
 302                 end_freq = center_freq;
 303         else
 304                 end_freq = center_freq + bandwidth/2 - 10;
 305
 306         return end_freq;
 307 }
 308
 309 static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
 310                                             u32 center_freq,
 311                                             u32 bandwidth)
 312 {
 313         struct ieee80211_channel *c;
 314         u32 freq, start_freq, end_freq;
 315
 316         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 317         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 318
 319         for (freq = start_freq; freq <= end_freq; freq += 20) {
 320                 c = ieee80211_get_channel(wiphy, freq);
 321                 if (!c)
 322                         return -EINVAL;
 323
 324                 if (c->flags & IEEE80211_CHAN_RADAR)
 325                         return 1;
 326         }
 327         return 0;
 328 }
 329
 330
 331 int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
 332                                   const struct cfg80211_chan_def *chandef,
 333                                   enum nl80211_iftype iftype)
 334 {
 335         int width;
 336         int ret;
 337
 338         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 339                 return -EINVAL;
 340
 341         switch (iftype) {
 342         case NL80211_IFTYPE_ADHOC:
 343         case NL80211_IFTYPE_AP:
 344         case NL80211_IFTYPE_P2P_GO:
 345         case NL80211_IFTYPE_MESH_POINT:
 346                 width = cfg80211_chandef_get_width(chandef);
 347                 if (width < 0)
 348                         return -EINVAL;
 349
 350                 ret = cfg80211_get_chans_dfs_required(wiphy,
 351                                                       chandef->center_freq1,
 352                                                       width);
 353                 if (ret < 0)
 354                         return ret;
 355                 else if (ret > 0)
 356                         return BIT(chandef->width);
 357
 358                 if (!chandef->center_freq2)
 359                         return 0;
 360
 361                 ret = cfg80211_get_chans_dfs_required(wiphy,
 362                                                       chandef->center_freq2,
 363                                                       width);
 364                 if (ret < 0)
 365                         return ret;
 366                 else if (ret > 0)
 367                         return BIT(chandef->width);
 368
 369                 break;
 370         case NL80211_IFTYPE_STATION:
 371         case NL80211_IFTYPE_OCB:
 372         case NL80211_IFTYPE_P2P_CLIENT:
 373         case NL80211_IFTYPE_MONITOR:
 374         case NL80211_IFTYPE_AP_VLAN:
 375         case NL80211_IFTYPE_WDS:
 376         case NL80211_IFTYPE_P2P_DEVICE:
 377         case NL80211_IFTYPE_NAN:
 378                 break;
 379         case NL80211_IFTYPE_UNSPECIFIED:
 380         case NUM_NL80211_IFTYPES:
 381                 WARN_ON(1);
 382         }
 383
 384         return 0;
 385 }
 386 EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
 387
 388 static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
 389                                          u32 center_freq,
 390                                          u32 bandwidth)
 391 {
 392         struct ieee80211_channel *c;
 393         u32 freq, start_freq, end_freq;
 394         int count = 0;
 395
 396         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 397         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 398
 399         /*
 400          * Check entire range of channels for the bandwidth.
 401          * Check all channels are DFS channels (DFS_USABLE or
 402          * DFS_AVAILABLE). Return number of usable channels
 403          * (require CAC). Allow DFS and non-DFS channel mix.
 404          */
 405         for (freq = start_freq; freq <= end_freq; freq += 20) {
 406                 c = ieee80211_get_channel(wiphy, freq);
 407                 if (!c)
 408                         return -EINVAL;
 409
 410                 if (c->flags & IEEE80211_CHAN_DISABLED)
 411                         return -EINVAL;
 412
 413                 if (c->flags & IEEE80211_CHAN_RADAR) {
 414                         if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
 415                                 return -EINVAL;
 416
 417                         if (c->dfs_state == NL80211_DFS_USABLE)
 418                                 count++;
 419                 }
 420         }
 421
 422         return count;
 423 }
 424
 425 bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
 426                                  const struct cfg80211_chan_def *chandef)
 427 {
 428         int width;
 429         int r1, r2 = 0;
 430
 431         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 432                 return false;
 433
 434         width = cfg80211_chandef_get_width(chandef);
 435         if (width < 0)
 436                 return false;
 437
 438         r1 = cfg80211_get_chans_dfs_usable(wiphy, chandef->center_freq1,
 439                                           width);
 440
 441         if (r1 < 0)
 442                 return false;
 443
 444         switch (chandef->width) {
 445         case NL80211_CHAN_WIDTH_80P80:
 446                 WARN_ON(!chandef->center_freq2);
 447                 r2 = cfg80211_get_chans_dfs_usable(wiphy,
 448                                                    chandef->center_freq2,
 449                                                    width);
 450                 if (r2 < 0)
 451                         return false;
 452                 break;
 453         default:
 454                 WARN_ON(chandef->center_freq2);
 455                 break;
 456         }
 457
 458         return (r1 + r2 > 0);
 459 }
 460
 461 /*
 462  * Checks if center frequency of chan falls with in the bandwidth
 463  * range of chandef.
 464  */
 465 bool cfg80211_is_sub_chan(struct cfg80211_chan_def *chandef,
 466                           struct ieee80211_channel *chan)
 467 {
 468         int width;
 469         u32 freq;
 470
 471         if (chandef->chan->center_freq == chan->center_freq)
 472                 return true;
 473
 474         width = cfg80211_chandef_get_width(chandef);
 475         if (width <= 20)
 476                 return false;
 477
 478         for (freq = chandef->center_freq1 - width / 2 + 10;
 479              freq <= chandef->center_freq1 + width / 2 - 10; freq += 20) {
 480                 if (chan->center_freq == freq)
 481                         return true;
 482         }
 483
 484         if (!chandef->center_freq2)
 485                 return false;
 486
 487         for (freq = chandef->center_freq2 - width / 2 + 10;
 488              freq <= chandef->center_freq2 + width / 2 - 10; freq += 20) {
 489                 if (chan->center_freq == freq)
 490                         return true;
 491         }
 492
 493         return false;
 494 }
 495
 496 bool cfg80211_beaconing_iface_active(struct wireless_dev *wdev)
 497 {
 498         bool active = false;
 499
 500         ASSERT_WDEV_LOCK(wdev);
 501
 502         if (!wdev->chandef.chan)
 503                 return false;
 504
 505         switch (wdev->iftype) {
 506         case NL80211_IFTYPE_AP:
 507         case NL80211_IFTYPE_P2P_GO:
 508                 active = wdev->beacon_interval != 0;
 509                 break;
 510         case NL80211_IFTYPE_ADHOC:
 511                 active = wdev->ssid_len != 0;
 512                 break;
 513         case NL80211_IFTYPE_MESH_POINT:
 514                 active = wdev->mesh_id_len != 0;
 515                 break;
 516         case NL80211_IFTYPE_STATION:
 517         case NL80211_IFTYPE_OCB:
 518         case NL80211_IFTYPE_P2P_CLIENT:
 519         case NL80211_IFTYPE_MONITOR:
 520         case NL80211_IFTYPE_AP_VLAN:
 521         case NL80211_IFTYPE_WDS:
 522         case NL80211_IFTYPE_P2P_DEVICE:
 523         /* Can NAN type be considered as beaconing interface? */
 524         case NL80211_IFTYPE_NAN:
 525                 break;
 526         case NL80211_IFTYPE_UNSPECIFIED:
 527         case NUM_NL80211_IFTYPES:
 528                 WARN_ON(1);
 529         }
 530
 531         return active;
 532 }
 533
 534 static bool cfg80211_is_wiphy_oper_chan(struct wiphy *wiphy,
 535                                         struct ieee80211_channel *chan)
 536 {
 537         struct wireless_dev *wdev;
 538
 539         list_for_each_entry(wdev, &wiphy->wdev_list, list) {
 540                 wdev_lock(wdev);
 541                 if (!cfg80211_beaconing_iface_active(wdev)) {
 542                         wdev_unlock(wdev);
 543                         continue;
 544                 }
 545
 546                 if (cfg80211_is_sub_chan(&wdev->chandef, chan)) {
 547                         wdev_unlock(wdev);
 548                         return true;
 549                 }
 550                 wdev_unlock(wdev);
 551         }
 552
 553         return false;
 554 }
 555
 556 bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
 557                                   struct ieee80211_channel *chan)
 558 {
 559         struct cfg80211_registered_device *rdev;
 560
 561         ASSERT_RTNL();
 562
 563         if (!(chan->flags & IEEE80211_CHAN_RADAR))
 564                 return false;
 565
 566         list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
 567                 if (!reg_dfs_domain_same(wiphy, &rdev->wiphy))
 568                         continue;
 569
 570                 if (cfg80211_is_wiphy_oper_chan(&rdev->wiphy, chan))
 571                         return true;
 572         }
 573
 574         return false;
 575 }
 576
 577 static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
 578                                              u32 center_freq,
 579                                              u32 bandwidth)
 580 {
 581         struct ieee80211_channel *c;
 582         u32 freq, start_freq, end_freq;
 583         bool dfs_offload;
 584
 585         dfs_offload = wiphy_ext_feature_isset(wiphy,
 586                                               NL80211_EXT_FEATURE_DFS_OFFLOAD);
 587
 588         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 589         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 590
 591         /*
 592          * Check entire range of channels for the bandwidth.
 593          * If any channel in between is disabled or has not
 594          * had gone through CAC return false
 595          */
 596         for (freq = start_freq; freq <= end_freq; freq += 20) {
 597                 c = ieee80211_get_channel(wiphy, freq);
 598                 if (!c)
 599                         return false;
 600
 601                 if (c->flags & IEEE80211_CHAN_DISABLED)
 602                         return false;
 603
 604                 if ((c->flags & IEEE80211_CHAN_RADAR) &&
 605                     (c->dfs_state != NL80211_DFS_AVAILABLE) &&
 606                     !(c->dfs_state == NL80211_DFS_USABLE && dfs_offload))
 607                         return false;
 608         }
 609
 610         return true;
 611 }
 612
 613 static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
 614                                 const struct cfg80211_chan_def *chandef)
 615 {
 616         int width;
 617         int r;
 618
 619         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 620                 return false;
 621
 622         width = cfg80211_chandef_get_width(chandef);
 623         if (width < 0)
 624                 return false;
 625
 626         r = cfg80211_get_chans_dfs_available(wiphy, chandef->center_freq1,
 627                                              width);
 628
 629         /* If any of channels unavailable for cf1 just return */
 630         if (!r)
 631                 return r;
 632
 633         switch (chandef->width) {
 634         case NL80211_CHAN_WIDTH_80P80:
 635                 WARN_ON(!chandef->center_freq2);
 636                 r = cfg80211_get_chans_dfs_available(wiphy,
 637                                                      chandef->center_freq2,
 638                                                      width);
 639                 break;
 640         default:
 641                 WARN_ON(chandef->center_freq2);
 642                 break;
 643         }
 644
 645         return r;
 646 }
 647
 648 static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
 649                                                     u32 center_freq,
 650                                                     u32 bandwidth)
 651 {
 652         struct ieee80211_channel *c;
 653         u32 start_freq, end_freq, freq;
 654         unsigned int dfs_cac_ms = 0;
 655
 656         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 657         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 658
 659         for (freq = start_freq; freq <= end_freq; freq += 20) {
 660                 c = ieee80211_get_channel(wiphy, freq);
 661                 if (!c)
 662                         return 0;
 663
 664                 if (c->flags & IEEE80211_CHAN_DISABLED)
 665                         return 0;
 666
 667                 if (!(c->flags & IEEE80211_CHAN_RADAR))
 668                         continue;
 669
 670                 if (c->dfs_cac_ms > dfs_cac_ms)
 671                         dfs_cac_ms = c->dfs_cac_ms;
 672         }
 673
 674         return dfs_cac_ms;
 675 }
 676
 677 unsigned int
 678 cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
 679                               const struct cfg80211_chan_def *chandef)
 680 {
 681         int width;
 682         unsigned int t1 = 0, t2 = 0;
 683
 684         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 685                 return 0;
 686
 687         width = cfg80211_chandef_get_width(chandef);
 688         if (width < 0)
 689                 return 0;
 690
 691         t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
 692                                              chandef->center_freq1,
 693                                              width);
 694
 695         if (!chandef->center_freq2)
 696                 return t1;
 697
 698         t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
 699                                              chandef->center_freq2,
 700                                              width);
 701
 702         return max(t1, t2);
 703 }
 704
 705 static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
 706                                         u32 center_freq, u32 bandwidth,
 707                                         u32 prohibited_flags)
 708 {
 709         struct ieee80211_channel *c;
 710         u32 freq, start_freq, end_freq;
 711
 712         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 713         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 714
 715         for (freq = start_freq; freq <= end_freq; freq += 20) {
 716                 c = ieee80211_get_channel(wiphy, freq);
 717                 if (!c || c->flags & prohibited_flags)
 718                         return false;
 719         }
 720
 721         return true;
 722 }
 723
 724 bool cfg80211_chandef_usable(struct wiphy *wiphy,
 725                              const struct cfg80211_chan_def *chandef,
 726                              u32 prohibited_flags)
 727 {
 728         struct ieee80211_sta_ht_cap *ht_cap;
 729         struct ieee80211_sta_vht_cap *vht_cap;
 730         u32 width, control_freq, cap;
 731
 732         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 733                 return false;
 734
 735         ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
 736         vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
 737
 738         control_freq = chandef->chan->center_freq;
 739
 740         switch (chandef->width) {
 741         case NL80211_CHAN_WIDTH_5:
 742                 width = 5;
 743                 break;
 744         case NL80211_CHAN_WIDTH_10:
 745                 prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
 746                 width = 10;
 747                 break;
 748         case NL80211_CHAN_WIDTH_20:
 749                 if (!ht_cap->ht_supported)
 750                         return false;
 751                 /* fall through */
 752         case NL80211_CHAN_WIDTH_20_NOHT:
 753                 prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
 754                 width = 20;
 755                 break;
 756         case NL80211_CHAN_WIDTH_40:
 757                 width = 40;
 758                 if (!ht_cap->ht_supported)
 759                         return false;
 760                 if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
 761                     ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
 762                         return false;
 763                 if (chandef->center_freq1 < control_freq &&
 764                     chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
 765                         return false;
 766                 if (chandef->center_freq1 > control_freq &&
 767                     chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
 768                         return false;
 769                 break;
 770         case NL80211_CHAN_WIDTH_80P80:
 771                 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 772                 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 773                         return false;
 774                 /* fall through */
 775         case NL80211_CHAN_WIDTH_80:
 776                 if (!vht_cap->vht_supported)
 777                         return false;
 778                 prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
 779                 width = 80;
 780                 break;
 781         case NL80211_CHAN_WIDTH_160:
 782                 if (!vht_cap->vht_supported)
 783                         return false;
 784                 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 785                 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
 786                     cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 787                         return false;
 788                 prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
 789                 width = 160;
 790                 break;
 791         default:
 792                 WARN_ON_ONCE(1);
 793                 return false;
 794         }
 795
 796         /*
 797          * TODO: What if there are only certain 80/160/80+80 MHz channels
 798          *       allowed by the driver, or only certain combinations?
 799          *       For 40 MHz the driver can set the NO_HT40 flags, but for
 800          *       80/160 MHz and in particular 80+80 MHz this isn't really
 801          *       feasible and we only have NO_80MHZ/NO_160MHZ so far but
 802          *       no way to cover 80+80 MHz or more complex restrictions.
 803          *       Note that such restrictions also need to be advertised to
 804          *       userspace, for example for P2P channel selection.
 805          */
 806
 807         if (width > 20)
 808                 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 809
 810         /* 5 and 10 MHz are only defined for the OFDM PHY */
 811         if (width < 20)
 812                 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 813
 814
 815         if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
 816                                          width, prohibited_flags))
 817                 return false;
 818
 819         if (!chandef->center_freq2)
 820                 return true;
 821         return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
 822                                            width, prohibited_flags);
 823 }
 824 EXPORT_SYMBOL(cfg80211_chandef_usable);
 825
 826 /*
 827  * Check if the channel can be used under permissive conditions mandated by
 828  * some regulatory bodies, i.e., the channel is marked with
 829  * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
 830  * associated to an AP on the same channel or on the same UNII band
 831  * (assuming that the AP is an authorized master).
 832  * In addition allow operation on a channel on which indoor operation is
 833  * allowed, iff we are currently operating in an indoor environment.
 834  */
 835 static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
 836                                         enum nl80211_iftype iftype,
 837                                         struct ieee80211_channel *chan)
 838 {
 839         struct wireless_dev *wdev;
 840         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 841
 842         ASSERT_RTNL();
 843
 844         if (!IS_ENABLED(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
 845             !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
 846                 return false;
 847
 848         /* only valid for GO and TDLS off-channel (station/p2p-CL) */
 849         if (iftype != NL80211_IFTYPE_P2P_GO &&
 850             iftype != NL80211_IFTYPE_STATION &&
 851             iftype != NL80211_IFTYPE_P2P_CLIENT)
 852                 return false;
 853
 854         if (regulatory_indoor_allowed() &&
 855             (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 856                 return true;
 857
 858         if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
 859                 return false;
 860
 861         /*
 862          * Generally, it is possible to rely on another device/driver to allow
 863          * the IR concurrent relaxation, however, since the device can further
 864          * enforce the relaxation (by doing a similar verifications as this),
 865          * and thus fail the GO instantiation, consider only the interfaces of
 866          * the current registered device.
 867          */
 868         list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
 869                 struct ieee80211_channel *other_chan = NULL;
 870                 int r1, r2;
 871
 872                 wdev_lock(wdev);
 873                 if (wdev->iftype == NL80211_IFTYPE_STATION &&
 874                     wdev->current_bss)
 875                         other_chan = wdev->current_bss->pub.channel;
 876
 877                 /*
 878                  * If a GO already operates on the same GO_CONCURRENT channel,
 879                  * this one (maybe the same one) can beacon as well. We allow
 880                  * the operation even if the station we relied on with
 881                  * GO_CONCURRENT is disconnected now. But then we must make sure
 882                  * we're not outdoor on an indoor-only channel.
 883                  */
 884                 if (iftype == NL80211_IFTYPE_P2P_GO &&
 885                     wdev->iftype == NL80211_IFTYPE_P2P_GO &&
 886                     wdev->beacon_interval &&
 887                     !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 888                         other_chan = wdev->chandef.chan;
 889                 wdev_unlock(wdev);
 890
 891                 if (!other_chan)
 892                         continue;
 893
 894                 if (chan == other_chan)
 895                         return true;
 896
 897                 if (chan->band != NL80211_BAND_5GHZ)
 898                         continue;
 899
 900                 r1 = cfg80211_get_unii(chan->center_freq);
 901                 r2 = cfg80211_get_unii(other_chan->center_freq);
 902
 903                 if (r1 != -EINVAL && r1 == r2) {
 904                         /*
 905                          * At some locations channels 149-165 are considered a
 906                          * bundle, but at other locations, e.g., Indonesia,
 907                          * channels 149-161 are considered a bundle while
 908                          * channel 165 is left out and considered to be in a
 909                          * different bundle. Thus, in case that there is a
 910                          * station interface connected to an AP on channel 165,
 911                          * it is assumed that channels 149-161 are allowed for
 912                          * GO operations. However, having a station interface
 913                          * connected to an AP on channels 149-161, does not
 914                          * allow GO operation on channel 165.
 915                          */
 916                         if (chan->center_freq == 5825 &&
 917                             other_chan->center_freq != 5825)
 918                                 continue;
 919                         return true;
 920                 }
 921         }
 922
 923         return false;
 924 }
 925
 926 static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
 927                                      struct cfg80211_chan_def *chandef,
 928                                      enum nl80211_iftype iftype,
 929                                      bool check_no_ir)
 930 {
 931         bool res;
 932         u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
 933                                IEEE80211_CHAN_RADAR;
 934
 935         trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 936
 937         if (check_no_ir)
 938                 prohibited_flags |= IEEE80211_CHAN_NO_IR;
 939
 940         if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
 941             cfg80211_chandef_dfs_available(wiphy, chandef)) {
 942                 /* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
 943                 prohibited_flags = IEEE80211_CHAN_DISABLED;
 944         }
 945
 946         res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
 947
 948         trace_cfg80211_return_bool(res);
 949         return res;
 950 }
 951
 952 bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
 953                              struct cfg80211_chan_def *chandef,
 954                              enum nl80211_iftype iftype)
 955 {
 956         return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
 957 }
 958 EXPORT_SYMBOL(cfg80211_reg_can_beacon);
 959
 960 bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
 961                                    struct cfg80211_chan_def *chandef,
 962                                    enum nl80211_iftype iftype)
 963 {
 964         bool check_no_ir;
 965
 966         ASSERT_RTNL();
 967
 968         /*
 969          * Under certain conditions suggested by some regulatory bodies a
 970          * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
 971          * only if such relaxations are not enabled and the conditions are not
 972          * met.
 973          */
 974         check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
 975                                                    chandef->chan);
 976
 977         return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 978 }
 979 EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
 980
 981 int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
 982                                  struct cfg80211_chan_def *chandef)
 983 {
 984         if (!rdev->ops->set_monitor_channel)
 985                 return -EOPNOTSUPP;
 986         if (!cfg80211_has_monitors_only(rdev))
 987                 return -EBUSY;
 988
 989         return rdev_set_monitor_channel(rdev, chandef);
 990 }
 991
 992 void
 993 cfg80211_get_chan_state(struct wireless_dev *wdev,
 994                         struct ieee80211_channel **chan,
 995                         enum cfg80211_chan_mode *chanmode,
 996                         u8 *radar_detect)
 997 {
 998         int ret;
 999
1000         *chan = NULL;
1001         *chanmode = CHAN_MODE_UNDEFINED;
1002
1003         ASSERT_WDEV_LOCK(wdev);
1004
1005         if (wdev->netdev && !netif_running(wdev->netdev))
1006                 return;
1007
1008         switch (wdev->iftype) {
1009         case NL80211_IFTYPE_ADHOC:
1010                 if (wdev->current_bss) {
1011                         *chan = wdev->current_bss->pub.channel;
1012                         *chanmode = (wdev->ibss_fixed &&
1013                                      !wdev->ibss_dfs_possible)
1014                                   ? CHAN_MODE_SHARED
1015                                   : CHAN_MODE_EXCLUSIVE;
1016
1017                         /* consider worst-case - IBSS can try to return to the
1018                          * original user-specified channel as creator */
1019                         if (wdev->ibss_dfs_possible)
1020                                 *radar_detect |= BIT(wdev->chandef.width);
1021                         return;
1022                 }
1023                 break;
1024         case NL80211_IFTYPE_STATION:
1025         case NL80211_IFTYPE_P2P_CLIENT:
1026                 if (wdev->current_bss) {
1027                         *chan = wdev->current_bss->pub.channel;
1028                         *chanmode = CHAN_MODE_SHARED;
1029                         return;
1030                 }
1031                 break;
1032         case NL80211_IFTYPE_AP:
1033         case NL80211_IFTYPE_P2P_GO:
1034                 if (wdev->cac_started) {
1035                         *chan = wdev->chandef.chan;
1036                         *chanmode = CHAN_MODE_SHARED;
1037                         *radar_detect |= BIT(wdev->chandef.width);
1038                 } else if (wdev->beacon_interval) {
1039                         *chan = wdev->chandef.chan;
1040                         *chanmode = CHAN_MODE_SHARED;
1041
1042                         ret = cfg80211_chandef_dfs_required(wdev->wiphy,
1043                                                             &wdev->chandef,
1044                                                             wdev->iftype);
1045                         WARN_ON(ret < 0);
1046                         if (ret > 0)
1047                                 *radar_detect |= BIT(wdev->chandef.width);
1048                 }
1049                 return;
1050         case NL80211_IFTYPE_MESH_POINT:
1051                 if (wdev->mesh_id_len) {
1052                         *chan = wdev->chandef.chan;
1053                         *chanmode = CHAN_MODE_SHARED;
1054
1055                         ret = cfg80211_chandef_dfs_required(wdev->wiphy,
1056                                                             &wdev->chandef,
1057                                                             wdev->iftype);
1058                         WARN_ON(ret < 0);
1059                         if (ret > 0)
1060                                 *radar_detect |= BIT(wdev->chandef.width);
1061                 }
1062                 return;
1063         case NL80211_IFTYPE_OCB:
1064                 if (wdev->chandef.chan) {
1065                         *chan = wdev->chandef.chan;
1066                         *chanmode = CHAN_MODE_SHARED;
1067                         return;
1068                 }
1069                 break;
1070         case NL80211_IFTYPE_MONITOR:
1071         case NL80211_IFTYPE_AP_VLAN:
1072         case NL80211_IFTYPE_WDS:
1073         case NL80211_IFTYPE_P2P_DEVICE:
1074         case NL80211_IFTYPE_NAN:
1075                 /* these interface types don't really have a channel */
1076                 return;
1077         case NL80211_IFTYPE_UNSPECIFIED:
1078         case NUM_NL80211_IFTYPES:
1079                 WARN_ON(1);
1080         }
1081 }