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
  21
  22 u8 * hostapd_eid_vht_capabilities(struct hostapd_data *hapd, u8 *eid)
  23 {
  24         struct ieee80211_vht_capabilities *cap;
  25         struct hostapd_hw_modes *mode = hapd->iface->current_mode;
  26         u8 *pos = eid;
  27
  28         if (!mode)
  29                 return eid;
  30
  31         if (mode->mode == HOSTAPD_MODE_IEEE80211G && hapd->conf->vendor_vht &&
  32             mode->vht_capab == 0 && hapd->iface->hw_features) {
  33                 int i;
  34
  35                 for (i = 0; i < hapd->iface->num_hw_features; i++) {
  36                         if (hapd->iface->hw_features[i].mode ==
  37                             HOSTAPD_MODE_IEEE80211A) {
  38                                 mode = &hapd->iface->hw_features[i];
  39                                 break;
  40                         }
  41                 }
  42         }
  43
  44         *pos++ = WLAN_EID_VHT_CAP;
  45         *pos++ = sizeof(*cap);
  46
  47         cap = (struct ieee80211_vht_capabilities *) pos;
  48         os_memset(cap, 0, sizeof(*cap));
  49         cap->vht_capabilities_info = host_to_le32(
  50                 hapd->iface->conf->vht_capab);
  51
  52         /* Supported MCS set comes from hw */
  53         os_memcpy(&cap->vht_supported_mcs_set, mode->vht_mcs_set, 8);
  54
  55         pos += sizeof(*cap);
  56
  57         return pos;
  58 }
  59
  60
  61 u8 * hostapd_eid_vht_operation(struct hostapd_data *hapd, u8 *eid)
  62 {
  63         struct ieee80211_vht_operation *oper;
  64         u8 *pos = eid;
  65
  66         *pos++ = WLAN_EID_VHT_OPERATION;
  67         *pos++ = sizeof(*oper);
  68
  69         oper = (struct ieee80211_vht_operation *) pos;
  70         os_memset(oper, 0, sizeof(*oper));
  71
  72         /*
  73          * center freq = 5 GHz + (5 * index)
  74          * So index 42 gives center freq 5.210 GHz
  75          * which is channel 42 in 5G band
  76          */
  77         oper->vht_op_info_chan_center_freq_seg0_idx =
  78                 hapd->iconf->vht_oper_centr_freq_seg0_idx;
  79         oper->vht_op_info_chan_center_freq_seg1_idx =
  80                 hapd->iconf->vht_oper_centr_freq_seg1_idx;
  81
  82         oper->vht_op_info_chwidth = hapd->iconf->vht_oper_chwidth;
  83
  84         /* VHT Basic MCS set comes from hw */
  85         /* Hard code 1 stream, MCS0-7 is a min Basic VHT MCS rates */
  86         oper->vht_basic_mcs_set = host_to_le16(0xfffc);
  87         pos += sizeof(*oper);
  88
  89         return pos;
  90 }
  91
  92
  93 static int check_valid_vht_mcs(struct hostapd_hw_modes *mode,
  94                                const u8 *sta_vht_capab)
  95 {
  96         const struct ieee80211_vht_capabilities *vht_cap;
  97         struct ieee80211_vht_capabilities ap_vht_cap;
  98         u16 sta_rx_mcs_set, ap_tx_mcs_set;
  99         int i;
 100
 101         if (!mode)
 102                 return 1;
 103
 104         /*
 105          * Disable VHT caps for STAs for which there is not even a single
 106          * allowed MCS in any supported number of streams, i.e., STA is
 107          * advertising 3 (not supported) as VHT MCS rates for all supported
 108          * stream cases.
 109          */
 110         os_memcpy(&ap_vht_cap.vht_supported_mcs_set, mode->vht_mcs_set,
 111                   sizeof(ap_vht_cap.vht_supported_mcs_set));
 112         vht_cap = (const struct ieee80211_vht_capabilities *) sta_vht_capab;
 113
 114         /* AP Tx MCS map vs. STA Rx MCS map */
 115         sta_rx_mcs_set = le_to_host16(vht_cap->vht_supported_mcs_set.rx_map);
 116         ap_tx_mcs_set = le_to_host16(ap_vht_cap.vht_supported_mcs_set.tx_map);
 117
 118         for (i = 0; i < VHT_RX_NSS_MAX_STREAMS; i++) {
 119                 if ((ap_tx_mcs_set & (0x3 << (i * 2))) == 3)
 120                         continue;
 121
 122                 if ((sta_rx_mcs_set & (0x3 << (i * 2))) == 3)
 123                         continue;
 124
 125                 return 1;
 126         }
 127
 128         wpa_printf(MSG_DEBUG,
 129                    "No matching VHT MCS found between AP TX and STA RX");
 130         return 0;
 131 }
 132
 133
 134 u8 * hostapd_eid_wb_chsw_wrapper(struct hostapd_data *hapd, u8 *eid)
 135 {
 136         u8 bw, chan1, chan2 = 0;
 137         int freq1;
 138
 139         if (!hapd->cs_freq_params.vht_enabled)
 140                 return eid;
 141
 142         /* bandwidth: 0: 40, 1: 80, 2: 160, 3: 80+80 */
 143         switch (hapd->cs_freq_params.bandwidth) {
 144         case 40:
 145                 bw = 0;
 146                 break;
 147         case 80:
 148                 /* check if it's 80+80 */
 149                 if (!hapd->cs_freq_params.center_freq2)
 150                         bw = 1;
 151                 else
 152                         bw = 3;
 153                 break;
 154         case 160:
 155                 bw = 2;
 156                 break;
 157         default:
 158                 /* not valid VHT bandwidth or not in CSA */
 159                 return eid;
 160         }
 161
 162         freq1 = hapd->cs_freq_params.center_freq1 ?
 163                 hapd->cs_freq_params.center_freq1 :
 164                 hapd->cs_freq_params.freq;
 165         if (ieee80211_freq_to_chan(freq1, &chan1) !=
 166             HOSTAPD_MODE_IEEE80211A)
 167                 return eid;
 168
 169         if (hapd->cs_freq_params.center_freq2 &&
 170             ieee80211_freq_to_chan(hapd->cs_freq_params.center_freq2,
 171                                    &chan2) != HOSTAPD_MODE_IEEE80211A)
 172                 return eid;
 173
 174         *eid++ = WLAN_EID_VHT_CHANNEL_SWITCH_WRAPPER;
 175         *eid++ = 5; /* Length of Channel Switch Wrapper */
 176         *eid++ = WLAN_EID_VHT_WIDE_BW_CHSWITCH;
 177         *eid++ = 3; /* Length of Wide Bandwidth Channel Switch element */
 178         *eid++ = bw; /* New Channel Width */
 179         *eid++ = chan1; /* New Channel Center Frequency Segment 0 */
 180         *eid++ = chan2; /* New Channel Center Frequency Segment 1 */
 181
 182         return eid;
 183 }
 184
 185
 186 u16 copy_sta_vht_capab(struct hostapd_data *hapd, struct sta_info *sta,
 187                        const u8 *vht_capab)
 188 {
 189         /* Disable VHT caps for STAs associated to no-VHT BSSes. */
 190         if (!vht_capab ||
 191             hapd->conf->disable_11ac ||
 192             !check_valid_vht_mcs(hapd->iface->current_mode, vht_capab)) {
 193                 sta->flags &= ~WLAN_STA_VHT;
 194                 os_free(sta->vht_capabilities);
 195                 sta->vht_capabilities = NULL;
 196                 return WLAN_STATUS_SUCCESS;
 197         }
 198
 199         if (sta->vht_capabilities == NULL) {
 200                 sta->vht_capabilities =
 201                         os_zalloc(sizeof(struct ieee80211_vht_capabilities));
 202                 if (sta->vht_capabilities == NULL)
 203                         return WLAN_STATUS_UNSPECIFIED_FAILURE;
 204         }
 205
 206         sta->flags |= WLAN_STA_VHT;
 207         os_memcpy(sta->vht_capabilities, vht_capab,
 208                   sizeof(struct ieee80211_vht_capabilities));
 209
 210         return WLAN_STATUS_SUCCESS;
 211 }
 212
 213
 214 u16 copy_sta_vendor_vht(struct hostapd_data *hapd, struct sta_info *sta,
 215                         const u8 *ie, size_t len)
 216 {
 217         const u8 *vht_capab;
 218         unsigned int vht_capab_len;
 219
 220         if (!ie || len < 5 + 2 + sizeof(struct ieee80211_vht_capabilities) ||
 221             hapd->conf->disable_11ac)
 222                 goto no_capab;
 223
 224         /* The VHT Capabilities element embedded in vendor VHT */
 225         vht_capab = ie + 5;
 226         if (vht_capab[0] != WLAN_EID_VHT_CAP)
 227                 goto no_capab;
 228         vht_capab_len = vht_capab[1];
 229         if (vht_capab_len < sizeof(struct ieee80211_vht_capabilities) ||
 230             (int) vht_capab_len > ie + len - vht_capab - 2)
 231                 goto no_capab;
 232         vht_capab += 2;
 233
 234         if (sta->vht_capabilities == NULL) {
 235                 sta->vht_capabilities =
 236                         os_zalloc(sizeof(struct ieee80211_vht_capabilities));
 237                 if (sta->vht_capabilities == NULL)
 238                         return WLAN_STATUS_UNSPECIFIED_FAILURE;
 239         }
 240
 241         sta->flags |= WLAN_STA_VHT | WLAN_STA_VENDOR_VHT;
 242         os_memcpy(sta->vht_capabilities, vht_capab,
 243                   sizeof(struct ieee80211_vht_capabilities));
 244         return WLAN_STATUS_SUCCESS;
 245
 246 no_capab:
 247         sta->flags &= ~WLAN_STA_VENDOR_VHT;
 248         return WLAN_STATUS_SUCCESS;
 249 }
 250
 251
 252 u8 * hostapd_eid_vendor_vht(struct hostapd_data *hapd, u8 *eid)
 253 {
 254         u8 *pos = eid;
 255
 256         if (!hapd->iface->current_mode)
 257                 return eid;
 258
 259         *pos++ = WLAN_EID_VENDOR_SPECIFIC;
 260         *pos++ = (5 +           /* The Vendor OUI, type and subtype */
 261                   2 + sizeof(struct ieee80211_vht_capabilities) +
 262                   2 + sizeof(struct ieee80211_vht_operation));
 263
 264         WPA_PUT_BE32(pos, (OUI_BROADCOM << 8) | VENDOR_VHT_TYPE);
 265         pos += 4;
 266         *pos++ = VENDOR_VHT_SUBTYPE;
 267         pos = hostapd_eid_vht_capabilities(hapd, pos);
 268         pos = hostapd_eid_vht_operation(hapd, pos);
 269
 270         return pos;
 271 }
 272
 273
 274 u16 set_sta_vht_opmode(struct hostapd_data *hapd, struct sta_info *sta,
 275                        const u8 *vht_oper_notif)
 276 {
 277         if (!vht_oper_notif) {
 278                 sta->flags &= ~WLAN_STA_VHT_OPMODE_ENABLED;
 279                 return WLAN_STATUS_SUCCESS;
 280         }
 281
 282         sta->flags |= WLAN_STA_VHT_OPMODE_ENABLED;
 283         sta->vht_opmode = *vht_oper_notif;
 284         return WLAN_STATUS_SUCCESS;
 285 }
 286
 287
 288 void hostapd_get_vht_capab(struct hostapd_data *hapd,
 289                            struct ieee80211_vht_capabilities *vht_cap,
 290                            struct ieee80211_vht_capabilities *neg_vht_cap)
 291 {
 292         u32 cap, own_cap, sym_caps;
 293
 294         if (vht_cap == NULL)
 295                 return;
 296         os_memcpy(neg_vht_cap, vht_cap, sizeof(*neg_vht_cap));
 297
 298         cap = le_to_host32(neg_vht_cap->vht_capabilities_info);
 299         own_cap = hapd->iconf->vht_capab;
 300
 301         /* mask out symmetric VHT capabilities we don't support */
 302         sym_caps = VHT_CAP_SHORT_GI_80 | VHT_CAP_SHORT_GI_160;
 303         cap &= ~sym_caps | (own_cap & sym_caps);
 304
 305         /* mask out beamformer/beamformee caps if not supported */
 306         if (!(own_cap & VHT_CAP_SU_BEAMFORMER_CAPABLE))
 307                 cap &= ~(VHT_CAP_SU_BEAMFORMEE_CAPABLE |
 308                          VHT_CAP_BEAMFORMEE_STS_MAX);
 309
 310         if (!(own_cap & VHT_CAP_SU_BEAMFORMEE_CAPABLE))
 311                 cap &= ~(VHT_CAP_SU_BEAMFORMER_CAPABLE |
 312                          VHT_CAP_SOUNDING_DIMENSION_MAX);
 313
 314         if (!(own_cap & VHT_CAP_MU_BEAMFORMER_CAPABLE))
 315                 cap &= ~VHT_CAP_MU_BEAMFORMEE_CAPABLE;
 316
 317         if (!(own_cap & VHT_CAP_MU_BEAMFORMEE_CAPABLE))
 318                 cap &= ~VHT_CAP_MU_BEAMFORMER_CAPABLE;
 319
 320         /* mask channel widths we don't support */
 321         switch (own_cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
 322         case VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
 323                 break;
 324         case VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
 325                 if (cap & VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
 326                         cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ;
 327                         cap |= VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
 328                 }
 329                 break;
 330         default:
 331                 cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_MASK;
 332                 break;
 333         }
 334
 335         if (!(cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK))
 336                 cap &= ~VHT_CAP_SHORT_GI_160;
 337
 338         /*
 339          * if we don't support RX STBC, mask out TX STBC in the STA's HT caps
 340          * if we don't support TX STBC, mask out RX STBC in the STA's HT caps
 341          */
 342         if (!(own_cap & VHT_CAP_RXSTBC_MASK))
 343                 cap &= ~VHT_CAP_TXSTBC;
 344         if (!(own_cap & VHT_CAP_TXSTBC))
 345                 cap &= ~VHT_CAP_RXSTBC_MASK;
 346
 347         neg_vht_cap->vht_capabilities_info = host_to_le32(cap);
 348 }