LXR linux/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
  15void 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}
  46EXPORT_SYMBOL(cfg80211_chandef_create);
  47
  48bool 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}
 115EXPORT_SYMBOL(cfg80211_chandef_valid);
 116
 117static 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
 153static 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
 185const struct cfg80211_chan_def *
 186cfg80211_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}
 238EXPORT_SYMBOL(cfg80211_chandef_compatible);
 239
 240static 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
 259void 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
 281static 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
 294static 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
 307static 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                        return 1;
 324        }
 325        return 0;
 326}
 327
 328
 329int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
 330                                  const struct cfg80211_chan_def *chandef,
 331                                  enum nl80211_iftype iftype)
 332{
 333        int width;
 334        int ret;
 335
 336        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 337                return -EINVAL;
 338
 339        switch (iftype) {
 340        case NL80211_IFTYPE_ADHOC:
 341        case NL80211_IFTYPE_AP:
 342        case NL80211_IFTYPE_P2P_GO:
 343        case NL80211_IFTYPE_MESH_POINT:
 344                width = cfg80211_chandef_get_width(chandef);
 345                if (width < 0)
 346                        return -EINVAL;
 347
 348                ret = cfg80211_get_chans_dfs_required(wiphy,
 349                                                      chandef->center_freq1,
 350                                                      width);
 351                if (ret < 0)
 352                        return ret;
 353                else if (ret > 0)
 354                        return BIT(chandef->width);
 355
 356                if (!chandef->center_freq2)
 357                        return 0;
 358
 359                ret = cfg80211_get_chans_dfs_required(wiphy,
 360                                                      chandef->center_freq2,
 361                                                      width);
 362                if (ret < 0)
 363                        return ret;
 364                else if (ret > 0)
 365                        return BIT(chandef->width);
 366
 367                break;
 368        case NL80211_IFTYPE_STATION:
 369        case NL80211_IFTYPE_OCB:
 370        case NL80211_IFTYPE_P2P_CLIENT:
 371        case NL80211_IFTYPE_MONITOR:
 372        case NL80211_IFTYPE_AP_VLAN:
 373        case NL80211_IFTYPE_WDS:
 374        case NL80211_IFTYPE_P2P_DEVICE:
 375                break;
 376        case NL80211_IFTYPE_UNSPECIFIED:
 377        case NUM_NL80211_IFTYPES:
 378                WARN_ON(1);
 379        }
 380
 381        return 0;
 382}
 383EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
 384
 385static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
 386                                         u32 center_freq,
 387                                         u32 bandwidth)
 388{
 389        struct ieee80211_channel *c;
 390        u32 freq, start_freq, end_freq;
 391        int count = 0;
 392
 393        start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 394        end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 395
 396        /*
 397         * Check entire range of channels for the bandwidth.
 398         * Check all channels are DFS channels (DFS_USABLE or
 399         * DFS_AVAILABLE). Return number of usable channels
 400         * (require CAC). Allow DFS and non-DFS channel mix.
 401         */
 402        for (freq = start_freq; freq <= end_freq; freq += 20) {
 403                c = ieee80211_get_channel(wiphy, freq);
 404                if (!c)
 405                        return -EINVAL;
 406
 407                if (c->flags & IEEE80211_CHAN_DISABLED)
 408                        return -EINVAL;
 409
 410                if (c->flags & IEEE80211_CHAN_RADAR) {
 411                        if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
 412                                return -EINVAL;
 413
 414                        if (c->dfs_state == NL80211_DFS_USABLE)
 415                                count++;
 416                }
 417        }
 418
 419        return count;
 420}
 421
 422bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
 423                                 const struct cfg80211_chan_def *chandef)
 424{
 425        int width;
 426        int r1, r2 = 0;
 427
 428        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 429                return false;
 430
 431        width = cfg80211_chandef_get_width(chandef);
 432        if (width < 0)
 433                return false;
 434
 435        r1 = cfg80211_get_chans_dfs_usable(wiphy, chandef->center_freq1,
 436                                          width);
 437
 438        if (r1 < 0)
 439                return false;
 440
 441        switch (chandef->width) {
 442        case NL80211_CHAN_WIDTH_80P80:
 443                WARN_ON(!chandef->center_freq2);
 444                r2 = cfg80211_get_chans_dfs_usable(wiphy,
 445                                                   chandef->center_freq2,
 446                                                   width);
 447                if (r2 < 0)
 448                        return false;
 449                break;
 450        default:
 451                WARN_ON(chandef->center_freq2);
 452                break;
 453        }
 454
 455        return (r1 + r2 > 0);
 456}
 457
 458
 459static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
 460                                             u32 center_freq,
 461                                             u32 bandwidth)
 462{
 463        struct ieee80211_channel *c;
 464        u32 freq, start_freq, end_freq;
 465
 466        start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 467        end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 468
 469        /*
 470         * Check entire range of channels for the bandwidth.
 471         * If any channel in between is disabled or has not
 472         * had gone through CAC return false
 473         */
 474        for (freq = start_freq; freq <= end_freq; freq += 20) {
 475                c = ieee80211_get_channel(wiphy, freq);
 476                if (!c)
 477                        return false;
 478
 479                if (c->flags & IEEE80211_CHAN_DISABLED)
 480                        return false;
 481
 482                if ((c->flags & IEEE80211_CHAN_RADAR)  &&
 483                    (c->dfs_state != NL80211_DFS_AVAILABLE))
 484                        return false;
 485        }
 486
 487        return true;
 488}
 489
 490static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
 491                                const struct cfg80211_chan_def *chandef)
 492{
 493        int width;
 494        int r;
 495
 496        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 497                return false;
 498
 499        width = cfg80211_chandef_get_width(chandef);
 500        if (width < 0)
 501                return false;
 502
 503        r = cfg80211_get_chans_dfs_available(wiphy, chandef->center_freq1,
 504                                             width);
 505
 506        /* If any of channels unavailable for cf1 just return */
 507        if (!r)
 508                return r;
 509
 510        switch (chandef->width) {
 511        case NL80211_CHAN_WIDTH_80P80:
 512                WARN_ON(!chandef->center_freq2);
 513                r = cfg80211_get_chans_dfs_available(wiphy,
 514                                                     chandef->center_freq2,
 515                                                     width);
 516        default:
 517                WARN_ON(chandef->center_freq2);
 518                break;
 519        }
 520
 521        return r;
 522}
 523
 524static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
 525                                                    u32 center_freq,
 526                                                    u32 bandwidth)
 527{
 528        struct ieee80211_channel *c;
 529        u32 start_freq, end_freq, freq;
 530        unsigned int dfs_cac_ms = 0;
 531
 532        start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 533        end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 534
 535        for (freq = start_freq; freq <= end_freq; freq += 20) {
 536                c = ieee80211_get_channel(wiphy, freq);
 537                if (!c)
 538                        return 0;
 539
 540                if (c->flags & IEEE80211_CHAN_DISABLED)
 541                        return 0;
 542
 543                if (!(c->flags & IEEE80211_CHAN_RADAR))
 544                        continue;
 545
 546                if (c->dfs_cac_ms > dfs_cac_ms)
 547                        dfs_cac_ms = c->dfs_cac_ms;
 548        }
 549
 550        return dfs_cac_ms;
 551}
 552
 553unsigned int
 554cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
 555                              const struct cfg80211_chan_def *chandef)
 556{
 557        int width;
 558        unsigned int t1 = 0, t2 = 0;
 559
 560        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 561                return 0;
 562
 563        width = cfg80211_chandef_get_width(chandef);
 564        if (width < 0)
 565                return 0;
 566
 567        t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
 568                                             chandef->center_freq1,
 569                                             width);
 570
 571        if (!chandef->center_freq2)
 572                return t1;
 573
 574        t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
 575                                             chandef->center_freq2,
 576                                             width);
 577
 578        return max(t1, t2);
 579}
 580
 581static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
 582                                        u32 center_freq, u32 bandwidth,
 583                                        u32 prohibited_flags)
 584{
 585        struct ieee80211_channel *c;
 586        u32 freq, start_freq, end_freq;
 587
 588        start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 589        end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 590
 591        for (freq = start_freq; freq <= end_freq; freq += 20) {
 592                c = ieee80211_get_channel(wiphy, freq);
 593                if (!c || c->flags & prohibited_flags)
 594                        return false;
 595        }
 596
 597        return true;
 598}
 599
 600bool cfg80211_chandef_usable(struct wiphy *wiphy,
 601                             const struct cfg80211_chan_def *chandef,
 602                             u32 prohibited_flags)
 603{
 604        struct ieee80211_sta_ht_cap *ht_cap;
 605        struct ieee80211_sta_vht_cap *vht_cap;
 606        u32 width, control_freq, cap;
 607
 608        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 609                return false;
 610
 611        ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
 612        vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
 613
 614        control_freq = chandef->chan->center_freq;
 615
 616        switch (chandef->width) {
 617        case NL80211_CHAN_WIDTH_5:
 618                width = 5;
 619                break;
 620        case NL80211_CHAN_WIDTH_10:
 621                prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
 622                width = 10;
 623                break;
 624        case NL80211_CHAN_WIDTH_20:
 625                if (!ht_cap->ht_supported)
 626                        return false;
 627        case NL80211_CHAN_WIDTH_20_NOHT:
 628                prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
 629                width = 20;
 630                break;
 631        case NL80211_CHAN_WIDTH_40:
 632                width = 40;
 633                if (!ht_cap->ht_supported)
 634                        return false;
 635                if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
 636                    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
 637                        return false;
 638                if (chandef->center_freq1 < control_freq &&
 639                    chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
 640                        return false;
 641                if (chandef->center_freq1 > control_freq &&
 642                    chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
 643                        return false;
 644                break;
 645        case NL80211_CHAN_WIDTH_80P80:
 646                cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 647                if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 648                        return false;
 649        case NL80211_CHAN_WIDTH_80:
 650                if (!vht_cap->vht_supported)
 651                        return false;
 652                prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
 653                width = 80;
 654                break;
 655        case NL80211_CHAN_WIDTH_160:
 656                if (!vht_cap->vht_supported)
 657                        return false;
 658                cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 659                if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
 660                    cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 661                        return false;
 662                prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
 663                width = 160;
 664                break;
 665        default:
 666                WARN_ON_ONCE(1);
 667                return false;
 668        }
 669
 670        /*
 671         * TODO: What if there are only certain 80/160/80+80 MHz channels
 672         *       allowed by the driver, or only certain combinations?
 673         *       For 40 MHz the driver can set the NO_HT40 flags, but for
 674         *       80/160 MHz and in particular 80+80 MHz this isn't really
 675         *       feasible and we only have NO_80MHZ/NO_160MHZ so far but
 676         *       no way to cover 80+80 MHz or more complex restrictions.
 677         *       Note that such restrictions also need to be advertised to
 678         *       userspace, for example for P2P channel selection.
 679         */
 680
 681        if (width > 20)
 682                prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 683
 684        /* 5 and 10 MHz are only defined for the OFDM PHY */
 685        if (width < 20)
 686                prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 687
 688
 689        if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
 690                                         width, prohibited_flags))
 691                return false;
 692
 693        if (!chandef->center_freq2)
 694                return true;
 695        return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
 696                                           width, prohibited_flags);
 697}
 698EXPORT_SYMBOL(cfg80211_chandef_usable);
 699
 700/*
 701 * Check if the channel can be used under permissive conditions mandated by
 702 * some regulatory bodies, i.e., the channel is marked with
 703 * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
 704 * associated to an AP on the same channel or on the same UNII band
 705 * (assuming that the AP is an authorized master).
 706 * In addition allow operation on a channel on which indoor operation is
 707 * allowed, iff we are currently operating in an indoor environment.
 708 */
 709static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
 710                                        enum nl80211_iftype iftype,
 711                                        struct ieee80211_channel *chan)
 712{
 713        struct wireless_dev *wdev;
 714        struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 715
 716        ASSERT_RTNL();
 717
 718        if (!config_enabled(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
 719            !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
 720                return false;
 721
 722        /* only valid for GO and TDLS off-channel (station/p2p-CL) */
 723        if (iftype != NL80211_IFTYPE_P2P_GO &&
 724            iftype != NL80211_IFTYPE_STATION &&
 725            iftype != NL80211_IFTYPE_P2P_CLIENT)
 726                return false;
 727
 728        if (regulatory_indoor_allowed() &&
 729            (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 730                return true;
 731
 732        if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
 733                return false;
 734
 735        /*
 736         * Generally, it is possible to rely on another device/driver to allow
 737         * the IR concurrent relaxation, however, since the device can further
 738         * enforce the relaxation (by doing a similar verifications as this),
 739         * and thus fail the GO instantiation, consider only the interfaces of
 740         * the current registered device.
 741         */
 742        list_for_each_entry(wdev, &rdev->wdev_list, list) {
 743                struct ieee80211_channel *other_chan = NULL;
 744                int r1, r2;
 745
 746                wdev_lock(wdev);
 747                if (wdev->iftype == NL80211_IFTYPE_STATION &&
 748                    wdev->current_bss)
 749                        other_chan = wdev->current_bss->pub.channel;
 750
 751                /*
 752                 * If a GO already operates on the same GO_CONCURRENT channel,
 753                 * this one (maybe the same one) can beacon as well. We allow
 754                 * the operation even if the station we relied on with
 755                 * GO_CONCURRENT is disconnected now. But then we must make sure
 756                 * we're not outdoor on an indoor-only channel.
 757                 */
 758                if (iftype == NL80211_IFTYPE_P2P_GO &&
 759                    wdev->iftype == NL80211_IFTYPE_P2P_GO &&
 760                    wdev->beacon_interval &&
 761                    !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 762                        other_chan = wdev->chandef.chan;
 763                wdev_unlock(wdev);
 764
 765                if (!other_chan)
 766                        continue;
 767
 768                if (chan == other_chan)
 769                        return true;
 770
 771                if (chan->band != IEEE80211_BAND_5GHZ)
 772                        continue;
 773
 774                r1 = cfg80211_get_unii(chan->center_freq);
 775                r2 = cfg80211_get_unii(other_chan->center_freq);
 776
 777                if (r1 != -EINVAL && r1 == r2) {
 778                        /*
 779                         * At some locations channels 149-165 are considered a
 780                         * bundle, but at other locations, e.g., Indonesia,
 781                         * channels 149-161 are considered a bundle while
 782                         * channel 165 is left out and considered to be in a
 783                         * different bundle. Thus, in case that there is a
 784                         * station interface connected to an AP on channel 165,
 785                         * it is assumed that channels 149-161 are allowed for
 786                         * GO operations. However, having a station interface
 787                         * connected to an AP on channels 149-161, does not
 788                         * allow GO operation on channel 165.
 789                         */
 790                        if (chan->center_freq == 5825 &&
 791                            other_chan->center_freq != 5825)
 792                                continue;
 793                        return true;
 794                }
 795        }
 796
 797        return false;
 798}
 799
 800static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
 801                                     struct cfg80211_chan_def *chandef,
 802                                     enum nl80211_iftype iftype,
 803                                     bool check_no_ir)
 804{
 805        bool res;
 806        u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
 807                               IEEE80211_CHAN_RADAR;
 808
 809        trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 810
 811        if (check_no_ir)
 812                prohibited_flags |= IEEE80211_CHAN_NO_IR;
 813
 814        if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
 815            cfg80211_chandef_dfs_available(wiphy, chandef)) {
 816                /* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
 817                prohibited_flags = IEEE80211_CHAN_DISABLED;
 818        }
 819
 820        res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
 821
 822        trace_cfg80211_return_bool(res);
 823        return res;
 824}
 825
 826bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
 827                             struct cfg80211_chan_def *chandef,
 828                             enum nl80211_iftype iftype)
 829{
 830        return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
 831}
 832EXPORT_SYMBOL(cfg80211_reg_can_beacon);
 833
 834bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
 835                                   struct cfg80211_chan_def *chandef,
 836                                   enum nl80211_iftype iftype)
 837{
 838        bool check_no_ir;
 839
 840        ASSERT_RTNL();
 841
 842        /*
 843         * Under certain conditions suggested by some regulatory bodies a
 844         * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
 845         * only if such relaxations are not enabled and the conditions are not
 846         * met.
 847         */
 848        check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
 849                                                   chandef->chan);
 850
 851        return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 852}
 853EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
 854
 855int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
 856                                 struct cfg80211_chan_def *chandef)
 857{
 858        if (!rdev->ops->set_monitor_channel)
 859                return -EOPNOTSUPP;
 860        if (!cfg80211_has_monitors_only(rdev))
 861                return -EBUSY;
 862
 863        return rdev_set_monitor_channel(rdev, chandef);
 864}
 865
 866void
 867cfg80211_get_chan_state(struct wireless_dev *wdev,
 868                        struct ieee80211_channel **chan,
 869                        enum cfg80211_chan_mode *chanmode,
 870                        u8 *radar_detect)
 871{
 872        int ret;
 873
 874        *chan = NULL;
 875        *chanmode = CHAN_MODE_UNDEFINED;
 876
 877        ASSERT_WDEV_LOCK(wdev);
 878
 879        if (wdev->netdev && !netif_running(wdev->netdev))
 880                return;
 881
 882        switch (wdev->iftype) {
 883        case NL80211_IFTYPE_ADHOC:
 884                if (wdev->current_bss) {
 885                        *chan = wdev->current_bss->pub.channel;
 886                        *chanmode = (wdev->ibss_fixed &&
 887                                     !wdev->ibss_dfs_possible)
 888                                  ? CHAN_MODE_SHARED
 889                                  : CHAN_MODE_EXCLUSIVE;
 890
 891                        /* consider worst-case - IBSS can try to return to the
 892                         * original user-specified channel as creator */
 893                        if (wdev->ibss_dfs_possible)
 894                                *radar_detect |= BIT(wdev->chandef.width);
 895                        return;
 896                }
 897                break;
 898        case NL80211_IFTYPE_STATION:
 899        case NL80211_IFTYPE_P2P_CLIENT:
 900                if (wdev->current_bss) {
 901                        *chan = wdev->current_bss->pub.channel;
 902                        *chanmode = CHAN_MODE_SHARED;
 903                        return;
 904                }
 905                break;
 906        case NL80211_IFTYPE_AP:
 907        case NL80211_IFTYPE_P2P_GO:
 908                if (wdev->cac_started) {
 909                        *chan = wdev->chandef.chan;
 910                        *chanmode = CHAN_MODE_SHARED;
 911                        *radar_detect |= BIT(wdev->chandef.width);
 912                } else if (wdev->beacon_interval) {
 913                        *chan = wdev->chandef.chan;
 914                        *chanmode = CHAN_MODE_SHARED;
 915
 916                        ret = cfg80211_chandef_dfs_required(wdev->wiphy,
 917                                                            &wdev->chandef,
 918                                                            wdev->iftype);
 919                        WARN_ON(ret < 0);
 920                        if (ret > 0)
 921                                *radar_detect |= BIT(wdev->chandef.width);
 922                }
 923                return;
 924        case NL80211_IFTYPE_MESH_POINT:
 925                if (wdev->mesh_id_len) {
 926                        *chan = wdev->chandef.chan;
 927                        *chanmode = CHAN_MODE_SHARED;
 928
 929                        ret = cfg80211_chandef_dfs_required(wdev->wiphy,
 930                                                            &wdev->chandef,
 931                                                            wdev->iftype);
 932                        WARN_ON(ret < 0);
 933                        if (ret > 0)
 934                                *radar_detect |= BIT(wdev->chandef.width);
 935                }
 936                return;
 937        case NL80211_IFTYPE_OCB:
 938                if (wdev->chandef.chan) {
 939                        *chan = wdev->chandef.chan;
 940                        *chanmode = CHAN_MODE_SHARED;
 941                        return;
 942                }
 943                break;
 944        case NL80211_IFTYPE_MONITOR:
 945        case NL80211_IFTYPE_AP_VLAN:
 946        case NL80211_IFTYPE_WDS:
 947        case NL80211_IFTYPE_P2P_DEVICE:
 948                /* these interface types don't really have a channel */
 949                return;
 950        case NL80211_IFTYPE_UNSPECIFIED:
 951        case NUM_NL80211_IFTYPES:
 952                WARN_ON(1);
 953        }
 954}
 955