src/ap/ieee802_11_vht.c

   1 /*
   2  * hostapd / IEEE 802.11ac VHT
   3  * Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of BSD license
   7  *
   8  * See README and COPYING for more details.
   9  */
  10
  11 #include "utils/includes.h"
  12
  13 #include "utils/common.h"
  14 #include "common/ieee802_11_defs.h"
  15 #include "hostapd.h"
  16 #include "ap_config.h"
  17 #include "sta_info.h"
  18 #include "beacon.h"
  19 #include "ieee802_11.h"
  20 #include "dfs.h"
  21
  22
  23 u8 * hostapd_eid_vht_capabilities(struct hostapd_data *hapd, u8 *eid, u32 nsts)
  24 {
  25         struct ieee80211_vht_capabilities *cap;
  26         struct hostapd_hw_modes *mode = hapd->iface->current_mode;
  27         u8 *pos = eid;
  28
  29         if (!mode)
  30                 return eid;
  31
  32         if (mode->mode == HOSTAPD_MODE_IEEE80211G && hapd->conf->vendor_vht &&
  33             mode->vht_capab == 0 && hapd->iface->hw_features) {
  34                 int i;
  35
  36                 for (i = 0; i < hapd->iface->num_hw_features; i++) {
  37                         if (hapd->iface->hw_features[i].mode ==
  38                             HOSTAPD_MODE_IEEE80211A) {
  39                                 mode = &hapd->iface->hw_features[i];
  40                                 break;
  41                         }
  42                 }
  43         }
  44
  45         *pos++ = WLAN_EID_VHT_CAP;
  46         *pos++ = sizeof(*cap);
  47
  48         cap = (struct ieee80211_vht_capabilities *) pos;
  49         os_memset(cap, 0, sizeof(*cap));
  50         cap->vht_capabilities_info = host_to_le32(
  51                 hapd->iface->conf->vht_capab);
  52
  53         if (nsts != 0) {
  54                 u32 hapd_nsts;
  55
  56                 hapd_nsts = le_to_host32(cap->vht_capabilities_info);
  57                 hapd_nsts = (hapd_nsts >> VHT_CAP_BEAMFORMEE_STS_OFFSET) & 7;
  58                 cap->vht_capabilities_info &=
  59                         ~(host_to_le32(hapd_nsts <<
  60                                        VHT_CAP_BEAMFORMEE_STS_OFFSET));
  61                 cap->vht_capabilities_info |=
  62                         host_to_le32(nsts << VHT_CAP_BEAMFORMEE_STS_OFFSET);
  63         }
  64
  65         /* Supported MCS set comes from hw */
  66         os_memcpy(&cap->vht_supported_mcs_set, mode->vht_mcs_set, 8);
  67
  68         pos += sizeof(*cap);
  69
  70         return pos;
  71 }
  72
  73
  74 u8 * hostapd_eid_vht_operation(struct hostapd_data *hapd, u8 *eid)
  75 {
  76         struct ieee80211_vht_operation *oper;
  77         u8 *pos = eid;
  78
  79         *pos++ = WLAN_EID_VHT_OPERATION;
  80         *pos++ = sizeof(*oper);
  81
  82         oper = (struct ieee80211_vht_operation *) pos;
  83         os_memset(oper, 0, sizeof(*oper));
  84
  85         /*
  86          * center freq = 5 GHz + (5 * index)
  87          * So index 42 gives center freq 5.210 GHz
  88          * which is channel 42 in 5G band
  89          */
  90         oper->vht_op_info_chan_center_freq_seg0_idx =
  91                 hapd->iconf->vht_oper_centr_freq_seg0_idx;
  92         oper->vht_op_info_chan_center_freq_seg1_idx =
  93                 hapd->iconf->vht_oper_centr_freq_seg1_idx;
  94
  95         oper->vht_op_info_chwidth = hapd->iconf->vht_oper_chwidth;
  96         if (hapd->iconf->vht_oper_chwidth == 2) {
  97                 /*
  98                  * Convert 160 MHz channel width to new style as interop
  99                  * workaround.
 100                  */
 101                 oper->vht_op_info_chwidth = 1;
 102                 oper->vht_op_info_chan_center_freq_seg1_idx =
 103                         oper->vht_op_info_chan_center_freq_seg0_idx;
 104                 if (hapd->iconf->channel <
 105                     hapd->iconf->vht_oper_centr_freq_seg0_idx)
 106                         oper->vht_op_info_chan_center_freq_seg0_idx -= 8;
 107                 else
 108                         oper->vht_op_info_chan_center_freq_seg0_idx += 8;
 109         } else if (hapd->iconf->vht_oper_chwidth == 3) {
 110                 /*
 111                  * Convert 80+80 MHz channel width to new style as interop
 112                  * workaround.
 113                  */
 114                 oper->vht_op_info_chwidth = 1;
 115         }
 116
 117         /* VHT Basic MCS set comes from hw */
 118         /* Hard code 1 stream, MCS0-7 is a min Basic VHT MCS rates */
 119         oper->vht_basic_mcs_set = host_to_le16(0xfffc);
 120         pos += sizeof(*oper);
 121
 122         return pos;
 123 }
 124
 125
 126 static int check_valid_vht_mcs(struct hostapd_hw_modes *mode,
 127                                const u8 *sta_vht_capab)
 128 {
 129         const struct ieee80211_vht_capabilities *vht_cap;
 130         struct ieee80211_vht_capabilities ap_vht_cap;
 131         u16 sta_rx_mcs_set, ap_tx_mcs_set;
 132         int i;
 133
 134         if (!mode)
 135                 return 1;
 136
 137         /*
 138          * Disable VHT caps for STAs for which there is not even a single
 139          * allowed MCS in any supported number of streams, i.e., STA is
 140          * advertising 3 (not supported) as VHT MCS rates for all supported
 141          * stream cases.
 142          */
 143         os_memcpy(&ap_vht_cap.vht_supported_mcs_set, mode->vht_mcs_set,
 144                   sizeof(ap_vht_cap.vht_supported_mcs_set));
 145         vht_cap = (const struct ieee80211_vht_capabilities *) sta_vht_capab;
 146
 147         /* AP Tx MCS map vs. STA Rx MCS map */
 148         sta_rx_mcs_set = le_to_host16(vht_cap->vht_supported_mcs_set.rx_map);
 149         ap_tx_mcs_set = le_to_host16(ap_vht_cap.vht_supported_mcs_set.tx_map);
 150
 151         for (i = 0; i < VHT_RX_NSS_MAX_STREAMS; i++) {
 152                 if ((ap_tx_mcs_set & (0x3 << (i * 2))) == 3)
 153                         continue;
 154
 155                 if ((sta_rx_mcs_set & (0x3 << (i * 2))) == 3)
 156                         continue;
 157
 158                 return 1;
 159         }
 160
 161         wpa_printf(MSG_DEBUG,
 162                    "No matching VHT MCS found between AP TX and STA RX");
 163         return 0;
 164 }
 165
 166
 167 u8 * hostapd_eid_wb_chsw_wrapper(struct hostapd_data *hapd, u8 *eid)
 168 {
 169         u8 bw, chan1, chan2 = 0;
 170         int freq1;
 171
 172         if (!hapd->cs_freq_params.channel ||
 173             !hapd->cs_freq_params.vht_enabled)
 174                 return eid;
 175
 176         /* bandwidth: 0: 40, 1: 80, 2: 160, 3: 80+80 */
 177         switch (hapd->cs_freq_params.bandwidth) {
 178         case 40:
 179                 bw = 0;
 180                 break;
 181         case 80:
 182                 /* check if it's 80+80 */
 183                 if (!hapd->cs_freq_params.center_freq2)
 184                         bw = 1;
 185                 else
 186                         bw = 3;
 187                 break;
 188         case 160:
 189                 bw = 2;
 190                 break;
 191         default:
 192                 /* not valid VHT bandwidth or not in CSA */
 193                 return eid;
 194         }
 195
 196         freq1 = hapd->cs_freq_params.center_freq1 ?
 197                 hapd->cs_freq_params.center_freq1 :
 198                 hapd->cs_freq_params.freq;
 199         if (ieee80211_freq_to_chan(freq1, &chan1) !=
 200             HOSTAPD_MODE_IEEE80211A)
 201                 return eid;
 202
 203         if (hapd->cs_freq_params.center_freq2 &&
 204             ieee80211_freq_to_chan(hapd->cs_freq_params.center_freq2,
 205                                    &chan2) != HOSTAPD_MODE_IEEE80211A)
 206                 return eid;
 207
 208         *eid++ = WLAN_EID_VHT_CHANNEL_SWITCH_WRAPPER;
 209         *eid++ = 5; /* Length of Channel Switch Wrapper */
 210         *eid++ = WLAN_EID_VHT_WIDE_BW_CHSWITCH;
 211         *eid++ = 3; /* Length of Wide Bandwidth Channel Switch element */
 212         *eid++ = bw; /* New Channel Width */
 213         *eid++ = chan1; /* New Channel Center Frequency Segment 0 */
 214         *eid++ = chan2; /* New Channel Center Frequency Segment 1 */
 215
 216         return eid;
 217 }
 218
 219
 220 u8 * hostapd_eid_txpower_envelope(struct hostapd_data *hapd, u8 *eid)
 221 {
 222         struct hostapd_iface *iface = hapd->iface;
 223         struct hostapd_config *iconf = iface->conf;
 224         struct hostapd_hw_modes *mode = iface->current_mode;
 225         struct hostapd_channel_data *chan;
 226         int dfs, i;
 227         u8 channel, tx_pwr_count, local_pwr_constraint;
 228         int max_tx_power;
 229         u8 tx_pwr;
 230
 231         if (!mode)
 232                 return eid;
 233
 234         if (ieee80211_freq_to_chan(iface->freq, &channel) == NUM_HOSTAPD_MODES)
 235                 return eid;
 236
 237         for (i = 0; i < mode->num_channels; i++) {
 238                 if (mode->channels[i].freq == iface->freq)
 239                         break;
 240         }
 241         if (i == mode->num_channels)
 242                 return eid;
 243
 244         switch (iface->conf->vht_oper_chwidth) {
 245         case VHT_CHANWIDTH_USE_HT:
 246                 if (iconf->secondary_channel == 0) {
 247                         /* Max Transmit Power count = 0 (20 MHz) */
 248                         tx_pwr_count = 0;
 249                 } else {
 250                         /* Max Transmit Power count = 1 (20, 40 MHz) */
 251                         tx_pwr_count = 1;
 252                 }
 253                 break;
 254         case VHT_CHANWIDTH_80MHZ:
 255                 /* Max Transmit Power count = 2 (20, 40, and 80 MHz) */
 256                 tx_pwr_count = 2;
 257                 break;
 258         case VHT_CHANWIDTH_80P80MHZ:
 259         case VHT_CHANWIDTH_160MHZ:
 260                 /* Max Transmit Power count = 3 (20, 40, 80, 160/80+80 MHz) */
 261                 tx_pwr_count = 3;
 262                 break;
 263         default:
 264                 return eid;
 265         }
 266
 267         /*
 268          * Below local_pwr_constraint logic is referred from
 269          * hostapd_eid_pwr_constraint.
 270          *
 271          * Check if DFS is required by regulatory.
 272          */
 273         dfs = hostapd_is_dfs_required(hapd->iface);
 274         if (dfs < 0)
 275                 dfs = 0;
 276
 277         /*
 278          * In order to meet regulations when TPC is not implemented using
 279          * a transmit power that is below the legal maximum (including any
 280          * mitigation factor) should help. In this case, indicate 3 dB below
 281          * maximum allowed transmit power.
 282          */
 283         if (hapd->iconf->local_pwr_constraint == -1)
 284                 local_pwr_constraint = (dfs == 0) ? 0 : 3;
 285         else
 286                 local_pwr_constraint = hapd->iconf->local_pwr_constraint;
 287
 288         /*
 289          * A STA that is not an AP shall use a transmit power less than or
 290          * equal to the local maximum transmit power level for the channel.
 291          * The local maximum transmit power can be calculated from the formula:
 292          * local max TX pwr = max TX pwr - local pwr constraint
 293          * Where max TX pwr is maximum transmit power level specified for
 294          * channel in Country element and local pwr constraint is specified
 295          * for channel in this Power Constraint element.
 296          */
 297         chan = &mode->channels[i];
 298         max_tx_power = chan->max_tx_power - local_pwr_constraint;
 299
 300         /*
 301          * Local Maximum Transmit power is encoded as two's complement
 302          * with a 0.5 dB step.
 303          */
 304         max_tx_power *= 2; /* in 0.5 dB steps */
 305         if (max_tx_power > 127) {
 306                 /* 63.5 has special meaning of 63.5 dBm or higher */
 307                 max_tx_power = 127;
 308         }
 309         if (max_tx_power < -128)
 310                 max_tx_power = -128;
 311         if (max_tx_power < 0)
 312                 tx_pwr = 0x80 + max_tx_power + 128;
 313         else
 314                 tx_pwr = max_tx_power;
 315
 316         *eid++ = WLAN_EID_VHT_TRANSMIT_POWER_ENVELOPE;
 317         *eid++ = 2 + tx_pwr_count;
 318
 319         /*
 320          * Max Transmit Power count and
 321          * Max Transmit Power units = 0 (EIRP)
 322          */
 323         *eid++ = tx_pwr_count;
 324
 325         for (i = 0; i <= tx_pwr_count; i++)
 326                 *eid++ = tx_pwr;
 327
 328         return eid;
 329 }
 330
 331
 332 u16 copy_sta_vht_capab(struct hostapd_data *hapd, struct sta_info *sta,
 333                        const u8 *vht_capab)
 334 {
 335         /* Disable VHT caps for STAs associated to no-VHT BSSes. */
 336         if (!vht_capab ||
 337             hapd->conf->disable_11ac ||
 338             !check_valid_vht_mcs(hapd->iface->current_mode, vht_capab)) {
 339                 sta->flags &= ~WLAN_STA_VHT;
 340                 os_free(sta->vht_capabilities);
 341                 sta->vht_capabilities = NULL;
 342                 return WLAN_STATUS_SUCCESS;
 343         }
 344
 345         if (sta->vht_capabilities == NULL) {
 346                 sta->vht_capabilities =
 347                         os_zalloc(sizeof(struct ieee80211_vht_capabilities));
 348                 if (sta->vht_capabilities == NULL)
 349                         return WLAN_STATUS_UNSPECIFIED_FAILURE;
 350         }
 351
 352         sta->flags |= WLAN_STA_VHT;
 353         os_memcpy(sta->vht_capabilities, vht_capab,
 354                   sizeof(struct ieee80211_vht_capabilities));
 355
 356         return WLAN_STATUS_SUCCESS;
 357 }
 358
 359
 360 u16 copy_sta_vendor_vht(struct hostapd_data *hapd, struct sta_info *sta,
 361                         const u8 *ie, size_t len)
 362 {
 363         const u8 *vht_capab;
 364         unsigned int vht_capab_len;
 365
 366         if (!ie || len < 5 + 2 + sizeof(struct ieee80211_vht_capabilities) ||
 367             hapd->conf->disable_11ac)
 368                 goto no_capab;
 369
 370         /* The VHT Capabilities element embedded in vendor VHT */
 371         vht_capab = ie + 5;
 372         if (vht_capab[0] != WLAN_EID_VHT_CAP)
 373                 goto no_capab;
 374         vht_capab_len = vht_capab[1];
 375         if (vht_capab_len < sizeof(struct ieee80211_vht_capabilities) ||
 376             (int) vht_capab_len > ie + len - vht_capab - 2)
 377                 goto no_capab;
 378         vht_capab += 2;
 379
 380         if (sta->vht_capabilities == NULL) {
 381                 sta->vht_capabilities =
 382                         os_zalloc(sizeof(struct ieee80211_vht_capabilities));
 383                 if (sta->vht_capabilities == NULL)
 384                         return WLAN_STATUS_UNSPECIFIED_FAILURE;
 385         }
 386
 387         sta->flags |= WLAN_STA_VHT | WLAN_STA_VENDOR_VHT;
 388         os_memcpy(sta->vht_capabilities, vht_capab,
 389                   sizeof(struct ieee80211_vht_capabilities));
 390         return WLAN_STATUS_SUCCESS;
 391
 392 no_capab:
 393         sta->flags &= ~WLAN_STA_VENDOR_VHT;
 394         return WLAN_STATUS_SUCCESS;
 395 }
 396
 397
 398 u8 * hostapd_eid_vendor_vht(struct hostapd_data *hapd, u8 *eid)
 399 {
 400         u8 *pos = eid;
 401
 402         if (!hapd->iface->current_mode)
 403                 return eid;
 404
 405         *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 406         *pos++ = (5 +           /* The Vendor OUI, type and subtype */
 407                   2 + sizeof(struct ieee80211_vht_capabilities) +
 408                   2 + sizeof(struct ieee80211_vht_operation));
 409
 410         WPA_PUT_BE32(pos, (OUI_BROADCOM << 8) | VENDOR_VHT_TYPE);
 411         pos += 4;
 412         *pos++ = VENDOR_VHT_SUBTYPE;
 413         pos = hostapd_eid_vht_capabilities(hapd, pos, 0);
 414         pos = hostapd_eid_vht_operation(hapd, pos);
 415
 416         return pos;
 417 }
 418
 419
 420 u16 set_sta_vht_opmode(struct hostapd_data *hapd, struct sta_info *sta,
 421                        const u8 *vht_oper_notif)
 422 {
 423         if (!vht_oper_notif) {
 424                 sta->flags &= ~WLAN_STA_VHT_OPMODE_ENABLED;
 425                 return WLAN_STATUS_SUCCESS;
 426         }
 427
 428         sta->flags |= WLAN_STA_VHT_OPMODE_ENABLED;
 429         sta->vht_opmode = *vht_oper_notif;
 430         return WLAN_STATUS_SUCCESS;
 431 }
 432
 433
 434 void hostapd_get_vht_capab(struct hostapd_data *hapd,
 435                            struct ieee80211_vht_capabilities *vht_cap,
 436                            struct ieee80211_vht_capabilities *neg_vht_cap)
 437 {
 438         u32 cap, own_cap, sym_caps;
 439
 440         if (vht_cap == NULL)
 441                 return;
 442         os_memcpy(neg_vht_cap, vht_cap, sizeof(*neg_vht_cap));
 443
 444         cap = le_to_host32(neg_vht_cap->vht_capabilities_info);
 445         own_cap = hapd->iconf->vht_capab;
 446
 447         /* mask out symmetric VHT capabilities we don't support */
 448         sym_caps = VHT_CAP_SHORT_GI_80 | VHT_CAP_SHORT_GI_160;
 449         cap &= ~sym_caps | (own_cap & sym_caps);
 450
 451         /* mask out beamformer/beamformee caps if not supported */
 452         if (!(own_cap & VHT_CAP_SU_BEAMFORMER_CAPABLE))
 453                 cap &= ~(VHT_CAP_SU_BEAMFORMEE_CAPABLE |
 454                          VHT_CAP_BEAMFORMEE_STS_MAX);
 455
 456         if (!(own_cap & VHT_CAP_SU_BEAMFORMEE_CAPABLE))
 457                 cap &= ~(VHT_CAP_SU_BEAMFORMER_CAPABLE |
 458                          VHT_CAP_SOUNDING_DIMENSION_MAX);
 459
 460         if (!(own_cap & VHT_CAP_MU_BEAMFORMER_CAPABLE))
 461                 cap &= ~VHT_CAP_MU_BEAMFORMEE_CAPABLE;
 462
 463         if (!(own_cap & VHT_CAP_MU_BEAMFORMEE_CAPABLE))
 464                 cap &= ~VHT_CAP_MU_BEAMFORMER_CAPABLE;
 465
 466         /* mask channel widths we don't support */
 467         switch (own_cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
 468         case VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
 469                 break;
 470         case VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
 471                 if (cap & VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
 472                         cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ;
 473                         cap |= VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
 474                 }
 475                 break;
 476         default:
 477                 cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 478                 break;
 479         }
 480
 481         if (!(cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK))
 482                 cap &= ~VHT_CAP_SHORT_GI_160;
 483
 484         /*
 485          * if we don't support RX STBC, mask out TX STBC in the STA's HT caps
 486          * if we don't support TX STBC, mask out RX STBC in the STA's HT caps
 487          */
 488         if (!(own_cap & VHT_CAP_RXSTBC_MASK))
 489                 cap &= ~VHT_CAP_TXSTBC;
 490         if (!(own_cap & VHT_CAP_TXSTBC))
 491                 cap &= ~VHT_CAP_RXSTBC_MASK;
 492
 493         neg_vht_cap->vht_capabilities_info = host_to_le32(cap);
 494 }