net/wireless/chan.c

   1 /*
   2  * This file contains helper code to handle channel
   3  * settings and keeping track of what is possible at
   4  * any point in time.
   5  *
   6  * Copyright 2009       Johannes Berg <johannes@sipsolutions.net>
   7  * Copyright 2013-2014  Intel Mobile Communications GmbH
   8  */
   9
  10 #include <linux/export.h>
  11 #include <net/cfg80211.h>
  12 #include "core.h"
  13 #include "rdev-ops.h"
  14
  15 void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
  16                              struct ieee80211_channel *chan,
  17                              enum nl80211_channel_type chan_type)
  18 {
  19         if (WARN_ON(!chan))
  20                 return;
  21
  22         chandef->chan = chan;
  23         chandef->center_freq2 = 0;
  24
  25         switch (chan_type) {
  26         case NL80211_CHAN_NO_HT:
  27                 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
  28                 chandef->center_freq1 = chan->center_freq;
  29                 break;
  30         case NL80211_CHAN_HT20:
  31                 chandef->width = NL80211_CHAN_WIDTH_20;
  32                 chandef->center_freq1 = chan->center_freq;
  33                 break;
  34         case NL80211_CHAN_HT40PLUS:
  35                 chandef->width = NL80211_CHAN_WIDTH_40;
  36                 chandef->center_freq1 = chan->center_freq + 10;
  37                 break;
  38         case NL80211_CHAN_HT40MINUS:
  39                 chandef->width = NL80211_CHAN_WIDTH_40;
  40                 chandef->center_freq1 = chan->center_freq - 10;
  41                 break;
  42         default:
  43                 WARN_ON(1);
  44         }
  45 }
  46 EXPORT_SYMBOL(cfg80211_chandef_create);
  47
  48 bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
  49 {
  50         u32 control_freq;
  51
  52         if (!chandef->chan)
  53                 return false;
  54
  55         control_freq = chandef->chan->center_freq;
  56
  57         switch (chandef->width) {
  58         case NL80211_CHAN_WIDTH_5:
  59         case NL80211_CHAN_WIDTH_10:
  60         case NL80211_CHAN_WIDTH_20:
  61         case NL80211_CHAN_WIDTH_20_NOHT:
  62                 if (chandef->center_freq1 != control_freq)
  63                         return false;
  64                 if (chandef->center_freq2)
  65                         return false;
  66                 break;
  67         case NL80211_CHAN_WIDTH_40:
  68                 if (chandef->center_freq1 != control_freq + 10 &&
  69                     chandef->center_freq1 != control_freq - 10)
  70                         return false;
  71                 if (chandef->center_freq2)
  72                         return false;
  73                 break;
  74         case NL80211_CHAN_WIDTH_80P80:
  75                 if (chandef->center_freq1 != control_freq + 30 &&
  76                     chandef->center_freq1 != control_freq + 10 &&
  77                     chandef->center_freq1 != control_freq - 10 &&
  78                     chandef->center_freq1 != control_freq - 30)
  79                         return false;
  80                 if (!chandef->center_freq2)
  81                         return false;
  82                 /* adjacent is not allowed -- that's a 160 MHz channel */
  83                 if (chandef->center_freq1 - chandef->center_freq2 == 80 ||
  84                     chandef->center_freq2 - chandef->center_freq1 == 80)
  85                         return false;
  86                 break;
  87         case NL80211_CHAN_WIDTH_80:
  88                 if (chandef->center_freq1 != control_freq + 30 &&
  89                     chandef->center_freq1 != control_freq + 10 &&
  90                     chandef->center_freq1 != control_freq - 10 &&
  91                     chandef->center_freq1 != control_freq - 30)
  92                         return false;
  93                 if (chandef->center_freq2)
  94                         return false;
  95                 break;
  96         case NL80211_CHAN_WIDTH_160:
  97                 if (chandef->center_freq1 != control_freq + 70 &&
  98                     chandef->center_freq1 != control_freq + 50 &&
  99                     chandef->center_freq1 != control_freq + 30 &&
 100                     chandef->center_freq1 != control_freq + 10 &&
 101                     chandef->center_freq1 != control_freq - 10 &&
 102                     chandef->center_freq1 != control_freq - 30 &&
 103                     chandef->center_freq1 != control_freq - 50 &&
 104                     chandef->center_freq1 != control_freq - 70)
 105                         return false;
 106                 if (chandef->center_freq2)
 107                         return false;
 108                 break;
 109         default:
 110                 return false;
 111         }
 112
 113         return true;
 114 }
 115 EXPORT_SYMBOL(cfg80211_chandef_valid);
 116
 117 static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
 118                                   u32 *pri40, u32 *pri80)
 119 {
 120         int tmp;
 121
 122         switch (c->width) {
 123         case NL80211_CHAN_WIDTH_40:
 124                 *pri40 = c->center_freq1;
 125                 *pri80 = 0;
 126                 break;
 127         case NL80211_CHAN_WIDTH_80:
 128         case NL80211_CHAN_WIDTH_80P80:
 129                 *pri80 = c->center_freq1;
 130                 /* n_P20 */
 131                 tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
 132                 /* n_P40 */
 133                 tmp /= 2;
 134                 /* freq_P40 */
 135                 *pri40 = c->center_freq1 - 20 + 40 * tmp;
 136                 break;
 137         case NL80211_CHAN_WIDTH_160:
 138                 /* n_P20 */
 139                 tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
 140                 /* n_P40 */
 141                 tmp /= 2;
 142                 /* freq_P40 */
 143                 *pri40 = c->center_freq1 - 60 + 40 * tmp;
 144                 /* n_P80 */
 145                 tmp /= 2;
 146                 *pri80 = c->center_freq1 - 40 + 80 * tmp;
 147                 break;
 148         default:
 149                 WARN_ON_ONCE(1);
 150         }
 151 }
 152
 153 static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
 154 {
 155         int width;
 156
 157         switch (c->width) {
 158         case NL80211_CHAN_WIDTH_5:
 159                 width = 5;
 160                 break;
 161         case NL80211_CHAN_WIDTH_10:
 162                 width = 10;
 163                 break;
 164         case NL80211_CHAN_WIDTH_20:
 165         case NL80211_CHAN_WIDTH_20_NOHT:
 166                 width = 20;
 167                 break;
 168         case NL80211_CHAN_WIDTH_40:
 169                 width = 40;
 170                 break;
 171         case NL80211_CHAN_WIDTH_80P80:
 172         case NL80211_CHAN_WIDTH_80:
 173                 width = 80;
 174                 break;
 175         case NL80211_CHAN_WIDTH_160:
 176                 width = 160;
 177                 break;
 178         default:
 179                 WARN_ON_ONCE(1);
 180                 return -1;
 181         }
 182         return width;
 183 }
 184
 185 const struct cfg80211_chan_def *
 186 cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
 187                             const struct cfg80211_chan_def *c2)
 188 {
 189         u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;
 190
 191         /* If they are identical, return */
 192         if (cfg80211_chandef_identical(c1, c2))
 193                 return c1;
 194
 195         /* otherwise, must have same control channel */
 196         if (c1->chan != c2->chan)
 197                 return NULL;
 198
 199         /*
 200          * If they have the same width, but aren't identical,
 201          * then they can't be compatible.
 202          */
 203         if (c1->width == c2->width)
 204                 return NULL;
 205
 206         /*
 207          * can't be compatible if one of them is 5 or 10 MHz,
 208          * but they don't have the same width.
 209          */
 210         if (c1->width == NL80211_CHAN_WIDTH_5 ||
 211             c1->width == NL80211_CHAN_WIDTH_10 ||
 212             c2->width == NL80211_CHAN_WIDTH_5 ||
 213             c2->width == NL80211_CHAN_WIDTH_10)
 214                 return NULL;
 215
 216         if (c1->width == NL80211_CHAN_WIDTH_20_NOHT ||
 217             c1->width == NL80211_CHAN_WIDTH_20)
 218                 return c2;
 219
 220         if (c2->width == NL80211_CHAN_WIDTH_20_NOHT ||
 221             c2->width == NL80211_CHAN_WIDTH_20)
 222                 return c1;
 223
 224         chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
 225         chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);
 226
 227         if (c1_pri40 != c2_pri40)
 228                 return NULL;
 229
 230         WARN_ON(!c1_pri80 && !c2_pri80);
 231         if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
 232                 return NULL;
 233
 234         if (c1->width > c2->width)
 235                 return c1;
 236         return c2;
 237 }
 238 EXPORT_SYMBOL(cfg80211_chandef_compatible);
 239
 240 static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
 241                                          u32 bandwidth,
 242                                          enum nl80211_dfs_state dfs_state)
 243 {
 244         struct ieee80211_channel *c;
 245         u32 freq;
 246
 247         for (freq = center_freq - bandwidth/2 + 10;
 248              freq <= center_freq + bandwidth/2 - 10;
 249              freq += 20) {
 250                 c = ieee80211_get_channel(wiphy, freq);
 251                 if (!c || !(c->flags & IEEE80211_CHAN_RADAR))
 252                         continue;
 253
 254                 c->dfs_state = dfs_state;
 255                 c->dfs_state_entered = jiffies;
 256         }
 257 }
 258
 259 void cfg80211_set_dfs_state(struct wiphy *wiphy,
 260                             const struct cfg80211_chan_def *chandef,
 261                             enum nl80211_dfs_state dfs_state)
 262 {
 263         int width;
 264
 265         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 266                 return;
 267
 268         width = cfg80211_chandef_get_width(chandef);
 269         if (width < 0)
 270                 return;
 271
 272         cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
 273                                      width, dfs_state);
 274
 275         if (!chandef->center_freq2)
 276                 return;
 277         cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
 278                                      width, dfs_state);
 279 }
 280
 281 static u32 cfg80211_get_start_freq(u32 center_freq,
 282                                    u32 bandwidth)
 283 {
 284         u32 start_freq;
 285
 286         if (bandwidth <= 20)
 287                 start_freq = center_freq;
 288         else
 289                 start_freq = center_freq - bandwidth/2 + 10;
 290
 291         return start_freq;
 292 }
 293
 294 static u32 cfg80211_get_end_freq(u32 center_freq,
 295                                  u32 bandwidth)
 296 {
 297         u32 end_freq;
 298
 299         if (bandwidth <= 20)
 300                 end_freq = center_freq;
 301         else
 302                 end_freq = center_freq + bandwidth/2 - 10;
 303
 304         return end_freq;
 305 }
 306
 307 static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
 308                                             u32 center_freq,
 309                                             u32 bandwidth)
 310 {
 311         struct ieee80211_channel *c;
 312         u32 freq, start_freq, end_freq;
 313
 314         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 315         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 316
 317         for (freq = start_freq; freq <= end_freq; freq += 20) {
 318                 c = ieee80211_get_channel(wiphy, freq);
 319                 if (!c)
 320                         return -EINVAL;
 321
 322                 if ((c->flags & IEEE80211_CHAN_RADAR) &&
 323                     !(wiphy->flags & WIPHY_FLAG_DFS_OFFLOAD))
 324                         return 1;
 325         }
 326         return 0;
 327 }
 328
 329
 330 int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
 331                                   const struct cfg80211_chan_def *chandef,
 332                                   enum nl80211_iftype iftype)
 333 {
 334         int width;
 335         int ret;
 336
 337         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 338                 return -EINVAL;
 339
 340         switch (iftype) {
 341         case NL80211_IFTYPE_ADHOC:
 342         case NL80211_IFTYPE_AP:
 343         case NL80211_IFTYPE_P2P_GO:
 344         case NL80211_IFTYPE_MESH_POINT:
 345                 width = cfg80211_chandef_get_width(chandef);
 346                 if (width < 0)
 347                         return -EINVAL;
 348
 349                 ret = cfg80211_get_chans_dfs_required(wiphy,
 350                                                       chandef->center_freq1,
 351                                                       width);
 352                 if (ret < 0)
 353                         return ret;
 354                 else if (ret > 0)
 355                         return BIT(chandef->width);
 356
 357                 if (!chandef->center_freq2)
 358                         return 0;
 359
 360                 ret = cfg80211_get_chans_dfs_required(wiphy,
 361                                                       chandef->center_freq2,
 362                                                       width);
 363                 if (ret < 0)
 364                         return ret;
 365                 else if (ret > 0)
 366                         return BIT(chandef->width);
 367
 368                 break;
 369         case NL80211_IFTYPE_STATION:
 370         case NL80211_IFTYPE_OCB:
 371         case NL80211_IFTYPE_P2P_CLIENT:
 372         case NL80211_IFTYPE_MONITOR:
 373         case NL80211_IFTYPE_AP_VLAN:
 374         case NL80211_IFTYPE_WDS:
 375         case NL80211_IFTYPE_P2P_DEVICE:
 376                 break;
 377         case NL80211_IFTYPE_UNSPECIFIED:
 378         case NUM_NL80211_IFTYPES:
 379                 WARN_ON(1);
 380         }
 381
 382         return 0;
 383 }
 384 EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
 385
 386 static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
 387                                          u32 center_freq,
 388                                          u32 bandwidth)
 389 {
 390         struct ieee80211_channel *c;
 391         u32 freq, start_freq, end_freq;
 392         int count = 0;
 393
 394         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 395         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 396
 397         /*
 398          * Check entire range of channels for the bandwidth.
 399          * Check all channels are DFS channels (DFS_USABLE or
 400          * DFS_AVAILABLE). Return number of usable channels
 401          * (require CAC). Allow DFS and non-DFS channel mix.
 402          */
 403         for (freq = start_freq; freq <= end_freq; freq += 20) {
 404                 c = ieee80211_get_channel(wiphy, freq);
 405                 if (!c)
 406                         return -EINVAL;
 407
 408                 if (c->flags & IEEE80211_CHAN_DISABLED)
 409                         return -EINVAL;
 410
 411                 if (c->flags & IEEE80211_CHAN_RADAR) {
 412                         if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
 413                                 return -EINVAL;
 414
 415                         if (c->dfs_state == NL80211_DFS_USABLE)
 416                                 count++;
 417                 }
 418         }
 419
 420         return count;
 421 }
 422
 423 bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
 424                                  const struct cfg80211_chan_def *chandef)
 425 {
 426         int width;
 427         int r1, r2 = 0;
 428
 429         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 430                 return false;
 431
 432         width = cfg80211_chandef_get_width(chandef);
 433         if (width < 0)
 434                 return false;
 435
 436         r1 = cfg80211_get_chans_dfs_usable(wiphy, chandef->center_freq1,
 437                                           width);
 438
 439         if (r1 < 0)
 440                 return false;
 441
 442         switch (chandef->width) {
 443         case NL80211_CHAN_WIDTH_80P80:
 444                 WARN_ON(!chandef->center_freq2);
 445                 r2 = cfg80211_get_chans_dfs_usable(wiphy,
 446                                                    chandef->center_freq2,
 447                                                    width);
 448                 if (r2 < 0)
 449                         return false;
 450                 break;
 451         default:
 452                 WARN_ON(chandef->center_freq2);
 453                 break;
 454         }
 455
 456         return (r1 + r2 > 0);
 457 }
 458
 459
 460 static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
 461                                              u32 center_freq,
 462                                              u32 bandwidth)
 463 {
 464         struct ieee80211_channel *c;
 465         u32 freq, start_freq, end_freq;
 466
 467         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 468         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 469
 470         /*
 471          * Check entire range of channels for the bandwidth.
 472          * If any channel in between is disabled or has not
 473          * had gone through CAC return false
 474          */
 475         for (freq = start_freq; freq <= end_freq; freq += 20) {
 476                 c = ieee80211_get_channel(wiphy, freq);
 477                 if (!c)
 478                         return false;
 479
 480                 if (c->flags & IEEE80211_CHAN_DISABLED)
 481                         return false;
 482
 483                 /* check for radar flags */
 484                 if ((!(wiphy->flags & WIPHY_FLAG_DFS_OFFLOAD)) &&
 485                     (c->flags & IEEE80211_CHAN_RADAR) &&
 486                     (c->dfs_state != NL80211_DFS_AVAILABLE))
 487                         return false;
 488         }
 489
 490         return true;
 491 }
 492
 493 static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
 494                                 const struct cfg80211_chan_def *chandef)
 495 {
 496         int width;
 497         int r;
 498
 499         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 500                 return false;
 501
 502         width = cfg80211_chandef_get_width(chandef);
 503         if (width < 0)
 504                 return false;
 505
 506         r = cfg80211_get_chans_dfs_available(wiphy, chandef->center_freq1,
 507                                              width);
 508
 509         /* If any of channels unavailable for cf1 just return */
 510         if (!r)
 511                 return r;
 512
 513         switch (chandef->width) {
 514         case NL80211_CHAN_WIDTH_80P80:
 515                 WARN_ON(!chandef->center_freq2);
 516                 r = cfg80211_get_chans_dfs_available(wiphy,
 517                                                      chandef->center_freq2,
 518                                                      width);
 519         default:
 520                 WARN_ON(chandef->center_freq2);
 521                 break;
 522         }
 523
 524         return r;
 525 }
 526
 527 static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
 528                                                     u32 center_freq,
 529                                                     u32 bandwidth)
 530 {
 531         struct ieee80211_channel *c;
 532         u32 start_freq, end_freq, freq;
 533         unsigned int dfs_cac_ms = 0;
 534
 535         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 536         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 537
 538         for (freq = start_freq; freq <= end_freq; freq += 20) {
 539                 c = ieee80211_get_channel(wiphy, freq);
 540                 if (!c)
 541                         return 0;
 542
 543                 if (c->flags & IEEE80211_CHAN_DISABLED)
 544                         return 0;
 545
 546                 if (!(c->flags & IEEE80211_CHAN_RADAR))
 547                         continue;
 548
 549                 if (c->dfs_cac_ms > dfs_cac_ms)
 550                         dfs_cac_ms = c->dfs_cac_ms;
 551         }
 552
 553         return dfs_cac_ms;
 554 }
 555
 556 unsigned int
 557 cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
 558                               const struct cfg80211_chan_def *chandef)
 559 {
 560         int width;
 561         unsigned int t1 = 0, t2 = 0;
 562
 563         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 564                 return 0;
 565
 566         width = cfg80211_chandef_get_width(chandef);
 567         if (width < 0)
 568                 return 0;
 569
 570         t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
 571                                              chandef->center_freq1,
 572                                              width);
 573
 574         if (!chandef->center_freq2)
 575                 return t1;
 576
 577         t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
 578                                              chandef->center_freq2,
 579                                              width);
 580
 581         return max(t1, t2);
 582 }
 583
 584 static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
 585                                         u32 center_freq, u32 bandwidth,
 586                                         u32 prohibited_flags)
 587 {
 588         struct ieee80211_channel *c;
 589         u32 freq, start_freq, end_freq;
 590
 591         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 592         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 593
 594         for (freq = start_freq; freq <= end_freq; freq += 20) {
 595                 c = ieee80211_get_channel(wiphy, freq);
 596
 597                 if (!c)
 598                         return false;
 599
 600                 if ((!(wiphy->flags & WIPHY_FLAG_DFS_OFFLOAD)) &&
 601                     (c->flags & prohibited_flags & IEEE80211_CHAN_RADAR))
 602                         return false;
 603
 604                 if (c->flags & prohibited_flags & ~IEEE80211_CHAN_RADAR)
 605                         return false;
 606         }
 607         return true;
 608 }
 609
 610 bool cfg80211_chandef_usable(struct wiphy *wiphy,
 611                              const struct cfg80211_chan_def *chandef,
 612                              u32 prohibited_flags)
 613 {
 614         struct ieee80211_sta_ht_cap *ht_cap;
 615         struct ieee80211_sta_vht_cap *vht_cap;
 616         u32 width, control_freq, cap;
 617
 618         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 619                 return false;
 620
 621         ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
 622         vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
 623
 624         control_freq = chandef->chan->center_freq;
 625
 626         switch (chandef->width) {
 627         case NL80211_CHAN_WIDTH_5:
 628                 width = 5;
 629                 break;
 630         case NL80211_CHAN_WIDTH_10:
 631                 prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
 632                 width = 10;
 633                 break;
 634         case NL80211_CHAN_WIDTH_20:
 635                 if (!ht_cap->ht_supported)
 636                         return false;
 637         case NL80211_CHAN_WIDTH_20_NOHT:
 638                 prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
 639                 width = 20;
 640                 break;
 641         case NL80211_CHAN_WIDTH_40:
 642                 width = 40;
 643                 if (!ht_cap->ht_supported)
 644                         return false;
 645                 if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
 646                     ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
 647                         return false;
 648                 if (chandef->center_freq1 < control_freq &&
 649                     chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
 650                         return false;
 651                 if (chandef->center_freq1 > control_freq &&
 652                     chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
 653                         return false;
 654                 break;
 655         case NL80211_CHAN_WIDTH_80P80:
 656                 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 657                 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 658                         return false;
 659         case NL80211_CHAN_WIDTH_80:
 660                 if (!vht_cap->vht_supported)
 661                         return false;
 662                 prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
 663                 width = 80;
 664                 break;
 665         case NL80211_CHAN_WIDTH_160:
 666                 if (!vht_cap->vht_supported)
 667                         return false;
 668                 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 669                 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
 670                     cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 671                         return false;
 672                 prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
 673                 width = 160;
 674                 break;
 675         default:
 676                 WARN_ON_ONCE(1);
 677                 return false;
 678         }
 679
 680         /*
 681          * TODO: What if there are only certain 80/160/80+80 MHz channels
 682          *       allowed by the driver, or only certain combinations?
 683          *       For 40 MHz the driver can set the NO_HT40 flags, but for
 684          *       80/160 MHz and in particular 80+80 MHz this isn't really
 685          *       feasible and we only have NO_80MHZ/NO_160MHZ so far but
 686          *       no way to cover 80+80 MHz or more complex restrictions.
 687          *       Note that such restrictions also need to be advertised to
 688          *       userspace, for example for P2P channel selection.
 689          */
 690
 691         if (width > 20)
 692                 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 693
 694         /* 5 and 10 MHz are only defined for the OFDM PHY */
 695         if (width < 20)
 696                 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 697
 698
 699         if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
 700                                          width, prohibited_flags))
 701                 return false;
 702
 703         if (!chandef->center_freq2)
 704                 return true;
 705         return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
 706                                            width, prohibited_flags);
 707 }
 708 EXPORT_SYMBOL(cfg80211_chandef_usable);
 709
 710 /*
 711  * Check if the channel can be used under permissive conditions mandated by
 712  * some regulatory bodies, i.e., the channel is marked with
 713  * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
 714  * associated to an AP on the same channel or on the same UNII band
 715  * (assuming that the AP is an authorized master).
 716  * In addition allow operation on a channel on which indoor operation is
 717  * allowed, iff we are currently operating in an indoor environment.
 718  */
 719 static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
 720                                         enum nl80211_iftype iftype,
 721                                         struct ieee80211_channel *chan)
 722 {
 723         struct wireless_dev *wdev;
 724         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 725
 726         ASSERT_RTNL();
 727
 728         if (!config_enabled(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
 729             !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
 730                 return false;
 731
 732         /* only valid for GO and TDLS off-channel (station/p2p-CL) */
 733         if (iftype != NL80211_IFTYPE_P2P_GO &&
 734             iftype != NL80211_IFTYPE_STATION &&
 735             iftype != NL80211_IFTYPE_P2P_CLIENT)
 736                 return false;
 737
 738         if (regulatory_indoor_allowed() &&
 739             (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 740                 return true;
 741
 742         if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
 743                 return false;
 744
 745         /*
 746          * Generally, it is possible to rely on another device/driver to allow
 747          * the IR concurrent relaxation, however, since the device can further
 748          * enforce the relaxation (by doing a similar verifications as this),
 749          * and thus fail the GO instantiation, consider only the interfaces of
 750          * the current registered device.
 751          */
 752         list_for_each_entry(wdev, &rdev->wdev_list, list) {
 753                 struct ieee80211_channel *other_chan = NULL;
 754                 int r1, r2;
 755
 756                 wdev_lock(wdev);
 757                 if (wdev->iftype == NL80211_IFTYPE_STATION &&
 758                     wdev->current_bss)
 759                         other_chan = wdev->current_bss->pub.channel;
 760
 761                 /*
 762                  * If a GO already operates on the same GO_CONCURRENT channel,
 763                  * this one (maybe the same one) can beacon as well. We allow
 764                  * the operation even if the station we relied on with
 765                  * GO_CONCURRENT is disconnected now. But then we must make sure
 766                  * we're not outdoor on an indoor-only channel.
 767                  */
 768                 if (iftype == NL80211_IFTYPE_P2P_GO &&
 769                     wdev->iftype == NL80211_IFTYPE_P2P_GO &&
 770                     wdev->beacon_interval &&
 771                     !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 772                         other_chan = wdev->chandef.chan;
 773                 wdev_unlock(wdev);
 774
 775                 if (!other_chan)
 776                         continue;
 777
 778                 if (chan == other_chan)
 779                         return true;
 780
 781                 if (chan->band != IEEE80211_BAND_5GHZ)
 782                         continue;
 783
 784                 r1 = cfg80211_get_unii(chan->center_freq);
 785                 r2 = cfg80211_get_unii(other_chan->center_freq);
 786
 787                 if (r1 != -EINVAL && r1 == r2) {
 788                         /*
 789                          * At some locations channels 149-165 are considered a
 790                          * bundle, but at other locations, e.g., Indonesia,
 791                          * channels 149-161 are considered a bundle while
 792                          * channel 165 is left out and considered to be in a
 793                          * different bundle. Thus, in case that there is a
 794                          * station interface connected to an AP on channel 165,
 795                          * it is assumed that channels 149-161 are allowed for
 796                          * GO operations. However, having a station interface
 797                          * connected to an AP on channels 149-161, does not
 798                          * allow GO operation on channel 165.
 799                          */
 800                         if (chan->center_freq == 5825 &&
 801                             other_chan->center_freq != 5825)
 802                                 continue;
 803                         return true;
 804                 }
 805         }
 806
 807         return false;
 808 }
 809
 810 static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
 811                                      struct cfg80211_chan_def *chandef,
 812                                      enum nl80211_iftype iftype,
 813                                      bool check_no_ir)
 814 {
 815         bool res;
 816         u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
 817                                IEEE80211_CHAN_RADAR;
 818
 819         trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 820
 821         if (check_no_ir)
 822                 prohibited_flags |= IEEE80211_CHAN_NO_IR;
 823
 824         if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
 825             cfg80211_chandef_dfs_available(wiphy, chandef)) {
 826                 /* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
 827                 prohibited_flags = IEEE80211_CHAN_DISABLED;
 828         }
 829
 830         res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
 831
 832         trace_cfg80211_return_bool(res);
 833         return res;
 834 }
 835
 836 bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
 837                              struct cfg80211_chan_def *chandef,
 838                              enum nl80211_iftype iftype)
 839 {
 840         return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
 841 }
 842 EXPORT_SYMBOL(cfg80211_reg_can_beacon);
 843
 844 bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
 845                                    struct cfg80211_chan_def *chandef,
 846                                    enum nl80211_iftype iftype)
 847 {
 848         bool check_no_ir;
 849
 850         ASSERT_RTNL();
 851
 852         /*
 853          * Under certain conditions suggested by some regulatory bodies a
 854          * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
 855          * only if such relaxations are not enabled and the conditions are not
 856          * met.
 857          */
 858         check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
 859                                                    chandef->chan);
 860
 861         return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 862 }
 863 EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
 864
 865 int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
 866                                  struct cfg80211_chan_def *chandef)
 867 {
 868         if (!rdev->ops->set_monitor_channel)
 869                 return -EOPNOTSUPP;
 870         if (!cfg80211_has_monitors_only(rdev))
 871                 return -EBUSY;
 872
 873         return rdev_set_monitor_channel(rdev, chandef);
 874 }
 875
 876 void
 877 cfg80211_get_chan_state(struct wireless_dev *wdev,
 878                         struct ieee80211_channel **chan,
 879                         enum cfg80211_chan_mode *chanmode,
 880                         u8 *radar_detect)
 881 {
 882         int ret;
 883
 884         *chan = NULL;
 885         *chanmode = CHAN_MODE_UNDEFINED;
 886
 887         ASSERT_WDEV_LOCK(wdev);
 888
 889         if (wdev->netdev && !netif_running(wdev->netdev))
 890                 return;
 891
 892         switch (wdev->iftype) {
 893         case NL80211_IFTYPE_ADHOC:
 894                 if (wdev->current_bss) {
 895                         *chan = wdev->current_bss->pub.channel;
 896                         *chanmode = (wdev->ibss_fixed &&
 897                                      !wdev->ibss_dfs_possible)
 898                                   ? CHAN_MODE_SHARED
 899                                   : CHAN_MODE_EXCLUSIVE;
 900
 901                         /* consider worst-case - IBSS can try to return to the
 902                          * original user-specified channel as creator */
 903                         if (wdev->ibss_dfs_possible)
 904                                 *radar_detect |= BIT(wdev->chandef.width);
 905                         return;
 906                 }
 907                 break;
 908         case NL80211_IFTYPE_STATION:
 909         case NL80211_IFTYPE_P2P_CLIENT:
 910                 if (wdev->current_bss) {
 911                         *chan = wdev->current_bss->pub.channel;
 912                         *chanmode = CHAN_MODE_SHARED;
 913                         return;
 914                 }
 915                 break;
 916         case NL80211_IFTYPE_AP:
 917         case NL80211_IFTYPE_P2P_GO:
 918                 if (wdev->cac_started) {
 919                         *chan = wdev->chandef.chan;
 920                         *chanmode = CHAN_MODE_SHARED;
 921                         *radar_detect |= BIT(wdev->chandef.width);
 922                 } else if (wdev->beacon_interval) {
 923                         *chan = wdev->chandef.chan;
 924                         *chanmode = CHAN_MODE_SHARED;
 925
 926                         ret = cfg80211_chandef_dfs_required(wdev->wiphy,
 927                                                             &wdev->chandef,
 928                                                             wdev->iftype);
 929                         WARN_ON(ret < 0);
 930                         if (ret > 0)
 931                                 *radar_detect |= BIT(wdev->chandef.width);
 932                 }
 933                 return;
 934         case NL80211_IFTYPE_MESH_POINT:
 935                 if (wdev->mesh_id_len) {
 936                         *chan = wdev->chandef.chan;
 937                         *chanmode = CHAN_MODE_SHARED;
 938
 939                         ret = cfg80211_chandef_dfs_required(wdev->wiphy,
 940                                                             &wdev->chandef,
 941                                                             wdev->iftype);
 942                         WARN_ON(ret < 0);
 943                         if (ret > 0)
 944                                 *radar_detect |= BIT(wdev->chandef.width);
 945                 }
 946                 return;
 947         case NL80211_IFTYPE_OCB:
 948                 if (wdev->chandef.chan) {
 949                         *chan = wdev->chandef.chan;
 950                         *chanmode = CHAN_MODE_SHARED;
 951                         return;
 952                 }
 953                 break;
 954         case NL80211_IFTYPE_MONITOR:
 955         case NL80211_IFTYPE_AP_VLAN:
 956         case NL80211_IFTYPE_WDS:
 957         case NL80211_IFTYPE_P2P_DEVICE:
 958                 /* these interface types don't really have a channel */
 959                 return;
 960         case NL80211_IFTYPE_UNSPECIFIED:
 961         case NUM_NL80211_IFTYPES:
 962                 WARN_ON(1);
 963         }
 964 }