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        case NL80211_IFTYPE_NAN:
 376                break;
 377        case NL80211_IFTYPE_UNSPECIFIED:
 378        case NUM_NL80211_IFTYPES:
 379                WARN_ON(1);
 380        }
 381
 382        return 0;
 383}
 384EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
 385
 386static 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
 423bool 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
 460static 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                if ((c->flags & IEEE80211_CHAN_RADAR)  &&
 484                    (c->dfs_state != NL80211_DFS_AVAILABLE))
 485                        return false;
 486        }
 487
 488        return true;
 489}
 490
 491static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
 492                                const struct cfg80211_chan_def *chandef)
 493{
 494        int width;
 495        int r;
 496
 497        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 498                return false;
 499
 500        width = cfg80211_chandef_get_width(chandef);
 501        if (width < 0)
 502                return false;
 503
 504        r = cfg80211_get_chans_dfs_available(wiphy, chandef->center_freq1,
 505                                             width);
 506
 507        /* If any of channels unavailable for cf1 just return */
 508        if (!r)
 509                return r;
 510
 511        switch (chandef->width) {
 512        case NL80211_CHAN_WIDTH_80P80:
 513                WARN_ON(!chandef->center_freq2);
 514                r = cfg80211_get_chans_dfs_available(wiphy,
 515                                                     chandef->center_freq2,
 516                                                     width);
 517                break;
 518        default:
 519                WARN_ON(chandef->center_freq2);
 520                break;
 521        }
 522
 523        return r;
 524}
 525
 526static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
 527                                                    u32 center_freq,
 528                                                    u32 bandwidth)
 529{
 530        struct ieee80211_channel *c;
 531        u32 start_freq, end_freq, freq;
 532        unsigned int dfs_cac_ms = 0;
 533
 534        start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 535        end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 536
 537        for (freq = start_freq; freq <= end_freq; freq += 20) {
 538                c = ieee80211_get_channel(wiphy, freq);
 539                if (!c)
 540                        return 0;
 541
 542                if (c->flags & IEEE80211_CHAN_DISABLED)
 543                        return 0;
 544
 545                if (!(c->flags & IEEE80211_CHAN_RADAR))
 546                        continue;
 547
 548                if (c->dfs_cac_ms > dfs_cac_ms)
 549                        dfs_cac_ms = c->dfs_cac_ms;
 550        }
 551
 552        return dfs_cac_ms;
 553}
 554
 555unsigned int
 556cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
 557                              const struct cfg80211_chan_def *chandef)
 558{
 559        int width;
 560        unsigned int t1 = 0, t2 = 0;
 561
 562        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 563                return 0;
 564
 565        width = cfg80211_chandef_get_width(chandef);
 566        if (width < 0)
 567                return 0;
 568
 569        t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
 570                                             chandef->center_freq1,
 571                                             width);
 572
 573        if (!chandef->center_freq2)
 574                return t1;
 575
 576        t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
 577                                             chandef->center_freq2,
 578                                             width);
 579
 580        return max(t1, t2);
 581}
 582
 583static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
 584                                        u32 center_freq, u32 bandwidth,
 585                                        u32 prohibited_flags)
 586{
 587        struct ieee80211_channel *c;
 588        u32 freq, start_freq, end_freq;
 589
 590        start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
 591        end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
 592
 593        for (freq = start_freq; freq <= end_freq; freq += 20) {
 594                c = ieee80211_get_channel(wiphy, freq);
 595                if (!c || c->flags & prohibited_flags)
 596                        return false;
 597        }
 598
 599        return true;
 600}
 601
 602bool cfg80211_chandef_usable(struct wiphy *wiphy,
 603                             const struct cfg80211_chan_def *chandef,
 604                             u32 prohibited_flags)
 605{
 606        struct ieee80211_sta_ht_cap *ht_cap;
 607        struct ieee80211_sta_vht_cap *vht_cap;
 608        u32 width, control_freq, cap;
 609
 610        if (WARN_ON(!cfg80211_chandef_valid(chandef)))
 611                return false;
 612
 613        ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
 614        vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
 615
 616        control_freq = chandef->chan->center_freq;
 617
 618        switch (chandef->width) {
 619        case NL80211_CHAN_WIDTH_5:
 620                width = 5;
 621                break;
 622        case NL80211_CHAN_WIDTH_10:
 623                prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
 624                width = 10;
 625                break;
 626        case NL80211_CHAN_WIDTH_20:
 627                if (!ht_cap->ht_supported)
 628                        return false;
 629        case NL80211_CHAN_WIDTH_20_NOHT:
 630                prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
 631                width = 20;
 632                break;
 633        case NL80211_CHAN_WIDTH_40:
 634                width = 40;
 635                if (!ht_cap->ht_supported)
 636                        return false;
 637                if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
 638                    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
 639                        return false;
 640                if (chandef->center_freq1 < control_freq &&
 641                    chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
 642                        return false;
 643                if (chandef->center_freq1 > control_freq &&
 644                    chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
 645                        return false;
 646                break;
 647        case NL80211_CHAN_WIDTH_80P80:
 648                cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 649                if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 650                        return false;
 651        case NL80211_CHAN_WIDTH_80:
 652                if (!vht_cap->vht_supported)
 653                        return false;
 654                prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
 655                width = 80;
 656                break;
 657        case NL80211_CHAN_WIDTH_160:
 658                if (!vht_cap->vht_supported)
 659                        return false;
 660                cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 661                if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
 662                    cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
 663                        return false;
 664                prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
 665                width = 160;
 666                break;
 667        default:
 668                WARN_ON_ONCE(1);
 669                return false;
 670        }
 671
 672        /*
 673         * TODO: What if there are only certain 80/160/80+80 MHz channels
 674         *       allowed by the driver, or only certain combinations?
 675         *       For 40 MHz the driver can set the NO_HT40 flags, but for
 676         *       80/160 MHz and in particular 80+80 MHz this isn't really
 677         *       feasible and we only have NO_80MHZ/NO_160MHZ so far but
 678         *       no way to cover 80+80 MHz or more complex restrictions.
 679         *       Note that such restrictions also need to be advertised to
 680         *       userspace, for example for P2P channel selection.
 681         */
 682
 683        if (width > 20)
 684                prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 685
 686        /* 5 and 10 MHz are only defined for the OFDM PHY */
 687        if (width < 20)
 688                prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
 689
 690
 691        if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
 692                                         width, prohibited_flags))
 693                return false;
 694
 695        if (!chandef->center_freq2)
 696                return true;
 697        return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
 698                                           width, prohibited_flags);
 699}
 700EXPORT_SYMBOL(cfg80211_chandef_usable);
 701
 702/*
 703 * Check if the channel can be used under permissive conditions mandated by
 704 * some regulatory bodies, i.e., the channel is marked with
 705 * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
 706 * associated to an AP on the same channel or on the same UNII band
 707 * (assuming that the AP is an authorized master).
 708 * In addition allow operation on a channel on which indoor operation is
 709 * allowed, iff we are currently operating in an indoor environment.
 710 */
 711static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
 712                                        enum nl80211_iftype iftype,
 713                                        struct ieee80211_channel *chan)
 714{
 715        struct wireless_dev *wdev;
 716        struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 717
 718        ASSERT_RTNL();
 719
 720        if (!IS_ENABLED(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
 721            !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
 722                return false;
 723
 724        /* only valid for GO and TDLS off-channel (station/p2p-CL) */
 725        if (iftype != NL80211_IFTYPE_P2P_GO &&
 726            iftype != NL80211_IFTYPE_STATION &&
 727            iftype != NL80211_IFTYPE_P2P_CLIENT)
 728                return false;
 729
 730        if (regulatory_indoor_allowed() &&
 731            (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 732                return true;
 733
 734        if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
 735                return false;
 736
 737        /*
 738         * Generally, it is possible to rely on another device/driver to allow
 739         * the IR concurrent relaxation, however, since the device can further
 740         * enforce the relaxation (by doing a similar verifications as this),
 741         * and thus fail the GO instantiation, consider only the interfaces of
 742         * the current registered device.
 743         */
 744        list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
 745                struct ieee80211_channel *other_chan = NULL;
 746                int r1, r2;
 747
 748                wdev_lock(wdev);
 749                if (wdev->iftype == NL80211_IFTYPE_STATION &&
 750                    wdev->current_bss)
 751                        other_chan = wdev->current_bss->pub.channel;
 752
 753                /*
 754                 * If a GO already operates on the same GO_CONCURRENT channel,
 755                 * this one (maybe the same one) can beacon as well. We allow
 756                 * the operation even if the station we relied on with
 757                 * GO_CONCURRENT is disconnected now. But then we must make sure
 758                 * we're not outdoor on an indoor-only channel.
 759                 */
 760                if (iftype == NL80211_IFTYPE_P2P_GO &&
 761                    wdev->iftype == NL80211_IFTYPE_P2P_GO &&
 762                    wdev->beacon_interval &&
 763                    !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
 764                        other_chan = wdev->chandef.chan;
 765                wdev_unlock(wdev);
 766
 767                if (!other_chan)
 768                        continue;
 769
 770                if (chan == other_chan)
 771                        return true;
 772
 773                if (chan->band != NL80211_BAND_5GHZ)
 774                        continue;
 775
 776                r1 = cfg80211_get_unii(chan->center_freq);
 777                r2 = cfg80211_get_unii(other_chan->center_freq);
 778
 779                if (r1 != -EINVAL && r1 == r2) {
 780                        /*
 781                         * At some locations channels 149-165 are considered a
 782                         * bundle, but at other locations, e.g., Indonesia,
 783                         * channels 149-161 are considered a bundle while
 784                         * channel 165 is left out and considered to be in a
 785                         * different bundle. Thus, in case that there is a
 786                         * station interface connected to an AP on channel 165,
 787                         * it is assumed that channels 149-161 are allowed for
 788                         * GO operations. However, having a station interface
 789                         * connected to an AP on channels 149-161, does not
 790                         * allow GO operation on channel 165.
 791                         */
 792                        if (chan->center_freq == 5825 &&
 793                            other_chan->center_freq != 5825)
 794                                continue;
 795                        return true;
 796                }
 797        }
 798
 799        return false;
 800}
 801
 802static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
 803                                     struct cfg80211_chan_def *chandef,
 804                                     enum nl80211_iftype iftype,
 805                                     bool check_no_ir)
 806{
 807        bool res;
 808        u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
 809                               IEEE80211_CHAN_RADAR;
 810
 811        trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 812
 813        if (check_no_ir)
 814                prohibited_flags |= IEEE80211_CHAN_NO_IR;
 815
 816        if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
 817            cfg80211_chandef_dfs_available(wiphy, chandef)) {
 818                /* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
 819                prohibited_flags = IEEE80211_CHAN_DISABLED;
 820        }
 821
 822        res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
 823
 824        trace_cfg80211_return_bool(res);
 825        return res;
 826}
 827
 828bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
 829                             struct cfg80211_chan_def *chandef,
 830                             enum nl80211_iftype iftype)
 831{
 832        return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
 833}
 834EXPORT_SYMBOL(cfg80211_reg_can_beacon);
 835
 836bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
 837                                   struct cfg80211_chan_def *chandef,
 838                                   enum nl80211_iftype iftype)
 839{
 840        bool check_no_ir;
 841
 842        ASSERT_RTNL();
 843
 844        /*
 845         * Under certain conditions suggested by some regulatory bodies a
 846         * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
 847         * only if such relaxations are not enabled and the conditions are not
 848         * met.
 849         */
 850        check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
 851                                                   chandef->chan);
 852
 853        return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
 854}
 855EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
 856
 857int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
 858                                 struct cfg80211_chan_def *chandef)
 859{
 860        if (!rdev->ops->set_monitor_channel)
 861                return -EOPNOTSUPP;
 862        if (!cfg80211_has_monitors_only(rdev))
 863                return -EBUSY;
 864
 865        return rdev_set_monitor_channel(rdev, chandef);
 866}
 867
 868void
 869cfg80211_get_chan_state(struct wireless_dev *wdev,
 870                        struct ieee80211_channel **chan,
 871                        enum cfg80211_chan_mode *chanmode,
 872                        u8 *radar_detect)
 873{
 874        int ret;
 875
 876        *chan = NULL;
 877        *chanmode = CHAN_MODE_UNDEFINED;
 878
 879        ASSERT_WDEV_LOCK(wdev);
 880
 881        if (wdev->netdev && !netif_running(wdev->netdev))
 882                return;
 883
 884        switch (wdev->iftype) {
 885        case NL80211_IFTYPE_ADHOC:
 886                if (wdev->current_bss) {
 887                        *chan = wdev->current_bss->pub.channel;
 888                        *chanmode = (wdev->ibss_fixed &&
 889                                     !wdev->ibss_dfs_possible)
 890                                  ? CHAN_MODE_SHARED
 891                                  : CHAN_MODE_EXCLUSIVE;
 892
 893                        /* consider worst-case - IBSS can try to return to the
 894                         * original user-specified channel as creator */
 895                        if (wdev->ibss_dfs_possible)
 896                                *radar_detect |= BIT(wdev->chandef.width);
 897                        return;
 898                }
 899                break;
 900        case NL80211_IFTYPE_STATION:
 901        case NL80211_IFTYPE_P2P_CLIENT:
 902                if (wdev->current_bss) {
 903                        *chan = wdev->current_bss->pub.channel;
 904                        *chanmode = CHAN_MODE_SHARED;
 905                        return;
 906                }
 907                break;
 908        case NL80211_IFTYPE_AP:
 909        case NL80211_IFTYPE_P2P_GO:
 910                if (wdev->cac_started) {
 911                        *chan = wdev->chandef.chan;
 912                        *chanmode = CHAN_MODE_SHARED;
 913                        *radar_detect |= BIT(wdev->chandef.width);
 914                } else if (wdev->beacon_interval) {
 915                        *chan = wdev->chandef.chan;
 916                        *chanmode = CHAN_MODE_SHARED;
 917
 918                        ret = cfg80211_chandef_dfs_required(wdev->wiphy,
 919                                                            &wdev->chandef,
 920                                                            wdev->iftype);
 921                        WARN_ON(ret < 0);
 922                        if (ret > 0)
 923                                *radar_detect |= BIT(wdev->chandef.width);
 924                }
 925                return;
 926        case NL80211_IFTYPE_MESH_POINT:
 927                if (wdev->mesh_id_len) {
 928                        *chan = wdev->chandef.chan;
 929                        *chanmode = CHAN_MODE_SHARED;
 930
 931                        ret = cfg80211_chandef_dfs_required(wdev->wiphy,
 932                                                            &wdev->chandef,
 933                                                            wdev->iftype);
 934                        WARN_ON(ret < 0);
 935                        if (ret > 0)
 936                                *radar_detect |= BIT(wdev->chandef.width);
 937                }
 938                return;
 939        case NL80211_IFTYPE_OCB:
 940                if (wdev->chandef.chan) {
 941                        *chan = wdev->chandef.chan;
 942                        *chanmode = CHAN_MODE_SHARED;
 943                        return;
 944                }
 945                break;
 946        case NL80211_IFTYPE_MONITOR:
 947        case NL80211_IFTYPE_AP_VLAN:
 948        case NL80211_IFTYPE_WDS:
 949        case NL80211_IFTYPE_P2P_DEVICE:
 950        case NL80211_IFTYPE_NAN:
 951                /* these interface types don't really have a channel */
 952                return;
 953        case NL80211_IFTYPE_UNSPECIFIED:
 954        case NUM_NL80211_IFTYPES:
 955                WARN_ON(1);
 956        }
 957}
 958