ieee802_11_ht.c revision 7832adbbd72a1b784b7fb74a71a5d4085b0cb0d3
1/* 2 * hostapd / IEEE 802.11n HT 3 * Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi> 4 * Copyright (c) 2007-2008, Intel Corporation 5 * 6 * This software may be distributed under the terms of the BSD license. 7 * See README for more details. 8 */ 9 10#include "utils/includes.h" 11 12#include "utils/common.h" 13#include "utils/eloop.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 "hw_features.h" 21#include "ap_drv_ops.h" 22 23 24u8 * hostapd_eid_ht_capabilities(struct hostapd_data *hapd, u8 *eid) 25{ 26 struct ieee80211_ht_capabilities *cap; 27 u8 *pos = eid; 28 29 if (!hapd->iconf->ieee80211n || !hapd->iface->current_mode || 30 hapd->conf->disable_11n) 31 return eid; 32 33 *pos++ = WLAN_EID_HT_CAP; 34 *pos++ = sizeof(*cap); 35 36 cap = (struct ieee80211_ht_capabilities *) pos; 37 os_memset(cap, 0, sizeof(*cap)); 38 cap->ht_capabilities_info = host_to_le16(hapd->iconf->ht_capab); 39 cap->a_mpdu_params = hapd->iface->current_mode->a_mpdu_params; 40 os_memcpy(cap->supported_mcs_set, hapd->iface->current_mode->mcs_set, 41 16); 42 43 /* TODO: ht_extended_capabilities (now fully disabled) */ 44 /* TODO: tx_bf_capability_info (now fully disabled) */ 45 /* TODO: asel_capabilities (now fully disabled) */ 46 47 pos += sizeof(*cap); 48 49 if (hapd->iconf->obss_interval) { 50 struct ieee80211_obss_scan_parameters *scan_params; 51 52 *pos++ = WLAN_EID_OVERLAPPING_BSS_SCAN_PARAMS; 53 *pos++ = sizeof(*scan_params); 54 55 scan_params = (struct ieee80211_obss_scan_parameters *) pos; 56 os_memset(scan_params, 0, sizeof(*scan_params)); 57 scan_params->width_trigger_scan_interval = 58 host_to_le16(hapd->iconf->obss_interval); 59 60 /* Fill in default values for remaining parameters 61 * (IEEE Std 802.11-2012, 8.4.2.61 and MIB defval) */ 62 scan_params->scan_passive_dwell = 63 host_to_le16(20); 64 scan_params->scan_active_dwell = 65 host_to_le16(10); 66 scan_params->scan_passive_total_per_channel = 67 host_to_le16(200); 68 scan_params->scan_active_total_per_channel = 69 host_to_le16(20); 70 scan_params->channel_transition_delay_factor = 71 host_to_le16(5); 72 scan_params->scan_activity_threshold = 73 host_to_le16(25); 74 75 pos += sizeof(*scan_params); 76 } 77 78 return pos; 79} 80 81 82u8 * hostapd_eid_ht_operation(struct hostapd_data *hapd, u8 *eid) 83{ 84 struct ieee80211_ht_operation *oper; 85 u8 *pos = eid; 86 87 if (!hapd->iconf->ieee80211n || hapd->conf->disable_11n) 88 return eid; 89 90 *pos++ = WLAN_EID_HT_OPERATION; 91 *pos++ = sizeof(*oper); 92 93 oper = (struct ieee80211_ht_operation *) pos; 94 os_memset(oper, 0, sizeof(*oper)); 95 96 oper->primary_chan = hapd->iconf->channel; 97 oper->operation_mode = host_to_le16(hapd->iface->ht_op_mode); 98 if (hapd->iconf->secondary_channel == 1) 99 oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE | 100 HT_INFO_HT_PARAM_STA_CHNL_WIDTH; 101 if (hapd->iconf->secondary_channel == -1) 102 oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW | 103 HT_INFO_HT_PARAM_STA_CHNL_WIDTH; 104 105 pos += sizeof(*oper); 106 107 return pos; 108} 109 110 111/* 112op_mode 113Set to 0 (HT pure) under the followign conditions 114 - all STAs in the BSS are 20/40 MHz HT in 20/40 MHz BSS or 115 - all STAs in the BSS are 20 MHz HT in 20 MHz BSS 116Set to 1 (HT non-member protection) if there may be non-HT STAs 117 in both the primary and the secondary channel 118Set to 2 if only HT STAs are associated in BSS, 119 however and at least one 20 MHz HT STA is associated 120Set to 3 (HT mixed mode) when one or more non-HT STAs are associated 121*/ 122int hostapd_ht_operation_update(struct hostapd_iface *iface) 123{ 124 u16 cur_op_mode, new_op_mode; 125 int op_mode_changes = 0; 126 127 if (!iface->conf->ieee80211n || iface->conf->ht_op_mode_fixed) 128 return 0; 129 130 wpa_printf(MSG_DEBUG, "%s current operation mode=0x%X", 131 __func__, iface->ht_op_mode); 132 133 if (!(iface->ht_op_mode & HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT) 134 && iface->num_sta_ht_no_gf) { 135 iface->ht_op_mode |= HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT; 136 op_mode_changes++; 137 } else if ((iface->ht_op_mode & 138 HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT) && 139 iface->num_sta_ht_no_gf == 0) { 140 iface->ht_op_mode &= ~HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT; 141 op_mode_changes++; 142 } 143 144 if (!(iface->ht_op_mode & HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) && 145 (iface->num_sta_no_ht || iface->olbc_ht)) { 146 iface->ht_op_mode |= HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT; 147 op_mode_changes++; 148 } else if ((iface->ht_op_mode & 149 HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) && 150 (iface->num_sta_no_ht == 0 && !iface->olbc_ht)) { 151 iface->ht_op_mode &= ~HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT; 152 op_mode_changes++; 153 } 154 155 if (iface->num_sta_no_ht) 156 new_op_mode = HT_PROT_NON_HT_MIXED; 157 else if (iface->conf->secondary_channel && iface->num_sta_ht_20mhz) 158 new_op_mode = HT_PROT_20MHZ_PROTECTION; 159 else if (iface->olbc_ht) 160 new_op_mode = HT_PROT_NONMEMBER_PROTECTION; 161 else 162 new_op_mode = HT_PROT_NO_PROTECTION; 163 164 cur_op_mode = iface->ht_op_mode & HT_OPER_OP_MODE_HT_PROT_MASK; 165 if (cur_op_mode != new_op_mode) { 166 iface->ht_op_mode &= ~HT_OPER_OP_MODE_HT_PROT_MASK; 167 iface->ht_op_mode |= new_op_mode; 168 op_mode_changes++; 169 } 170 171 wpa_printf(MSG_DEBUG, "%s new operation mode=0x%X changes=%d", 172 __func__, iface->ht_op_mode, op_mode_changes); 173 174 return op_mode_changes; 175} 176 177 178static int is_40_allowed(struct hostapd_iface *iface, int channel) 179{ 180 int pri_freq, sec_freq; 181 int affected_start, affected_end; 182 int pri = 2407 + 5 * channel; 183 184 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G) 185 return 1; 186 187 pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel); 188 189 if (iface->conf->secondary_channel > 0) 190 sec_freq = pri_freq + 20; 191 else 192 sec_freq = pri_freq - 20; 193 194 affected_start = (pri_freq + sec_freq) / 2 - 25; 195 affected_end = (pri_freq + sec_freq) / 2 + 25; 196 if ((pri < affected_start || pri > affected_end)) 197 return 1; /* not within affected channel range */ 198 199 wpa_printf(MSG_ERROR, "40 MHz affected channel range: [%d,%d] MHz", 200 affected_start, affected_end); 201 wpa_printf(MSG_ERROR, "Neighboring BSS: freq=%d", pri); 202 return 0; 203} 204 205 206void hostapd_2040_coex_action(struct hostapd_data *hapd, 207 const struct ieee80211_mgmt *mgmt, size_t len) 208{ 209 struct hostapd_iface *iface = hapd->iface; 210 struct ieee80211_2040_bss_coex_ie *bc_ie; 211 struct ieee80211_2040_intol_chan_report *ic_report; 212 int is_ht_allowed = 1; 213 int i; 214 const u8 *data = (const u8 *) &mgmt->u.action.u.public_action.action; 215 size_t hdr_len; 216 217 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211, 218 HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d", 219 mgmt->u.action.u.public_action.action); 220 221 if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) 222 return; 223 224 hdr_len = data - (u8 *) mgmt; 225 if (hdr_len > len) 226 return; 227 data++; 228 229 bc_ie = (struct ieee80211_2040_bss_coex_ie *) &data[0]; 230 ic_report = (struct ieee80211_2040_intol_chan_report *) 231 (&data[0] + sizeof(*bc_ie)); 232 233 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) { 234 hostapd_logger(hapd, mgmt->sa, 235 HOSTAPD_MODULE_IEEE80211, 236 HOSTAPD_LEVEL_DEBUG, 237 "20 MHz BSS width request bit is set in BSS coexistence information field"); 238 is_ht_allowed = 0; 239 } 240 241 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) { 242 hostapd_logger(hapd, mgmt->sa, 243 HOSTAPD_MODULE_IEEE80211, 244 HOSTAPD_LEVEL_DEBUG, 245 "40 MHz intolerant bit is set in BSS coexistence information field"); 246 is_ht_allowed = 0; 247 } 248 249 if (ic_report && 250 (ic_report->element_id == WLAN_EID_20_40_BSS_INTOLERANT)) { 251 /* Go through the channel report to find any BSS there in the 252 * affected channel range */ 253 for (i = 0; i < ic_report->length - 1; i++) { 254 if (is_40_allowed(iface, ic_report->variable[i])) 255 continue; 256 hostapd_logger(hapd, mgmt->sa, 257 HOSTAPD_MODULE_IEEE80211, 258 HOSTAPD_LEVEL_DEBUG, 259 "20_40_INTOLERANT channel %d reported", 260 ic_report->variable[i]); 261 is_ht_allowed = 0; 262 break; 263 } 264 } 265 266 if (!is_ht_allowed && 267 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 268 if (iface->conf->secondary_channel) { 269 hostapd_logger(hapd, mgmt->sa, 270 HOSTAPD_MODULE_IEEE80211, 271 HOSTAPD_LEVEL_INFO, 272 "Switching to 20 MHz operation"); 273 iface->conf->secondary_channel = 0; 274 ieee802_11_set_beacons(iface); 275 } 276 if (!iface->num_sta_ht40_intolerant) { 277 unsigned int delay_time; 278 delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR * 279 iface->conf->obss_interval; 280 eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface, 281 NULL); 282 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout, 283 hapd->iface, NULL); 284 } 285 } 286} 287 288 289u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta, 290 const u8 *ht_capab, size_t ht_capab_len) 291{ 292 /* Disable HT caps for STAs associated to no-HT BSSes. */ 293 if (!ht_capab || 294 ht_capab_len < sizeof(struct ieee80211_ht_capabilities) || 295 hapd->conf->disable_11n) { 296 sta->flags &= ~WLAN_STA_HT; 297 os_free(sta->ht_capabilities); 298 sta->ht_capabilities = NULL; 299 return WLAN_STATUS_SUCCESS; 300 } 301 302 if (sta->ht_capabilities == NULL) { 303 sta->ht_capabilities = 304 os_zalloc(sizeof(struct ieee80211_ht_capabilities)); 305 if (sta->ht_capabilities == NULL) 306 return WLAN_STATUS_UNSPECIFIED_FAILURE; 307 } 308 309 sta->flags |= WLAN_STA_HT; 310 os_memcpy(sta->ht_capabilities, ht_capab, 311 sizeof(struct ieee80211_ht_capabilities)); 312 313 return WLAN_STATUS_SUCCESS; 314} 315 316 317void ht40_intolerant_add(struct hostapd_iface *iface, struct sta_info *sta) 318{ 319 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G) 320 return; 321 322 wpa_printf(MSG_INFO, "HT: Forty MHz Intolerant is set by STA " MACSTR 323 " in Association Request", MAC2STR(sta->addr)); 324 325 if (sta->ht40_intolerant_set) 326 return; 327 328 sta->ht40_intolerant_set = 1; 329 iface->num_sta_ht40_intolerant++; 330 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL); 331 332 if (iface->conf->secondary_channel && 333 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 334 iface->conf->secondary_channel = 0; 335 ieee802_11_set_beacons(iface); 336 } 337} 338 339 340void ht40_intolerant_remove(struct hostapd_iface *iface, struct sta_info *sta) 341{ 342 if (!sta->ht40_intolerant_set) 343 return; 344 345 sta->ht40_intolerant_set = 0; 346 iface->num_sta_ht40_intolerant--; 347 348 if (iface->num_sta_ht40_intolerant == 0 && 349 (iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) && 350 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 351 unsigned int delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR * 352 iface->conf->obss_interval; 353 wpa_printf(MSG_DEBUG, 354 "HT: Start 20->40 MHz transition timer (%d seconds)", 355 delay_time); 356 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL); 357 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout, 358 iface, NULL); 359 } 360} 361 362 363static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta) 364{ 365 u16 ht_capab; 366 367 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info); 368 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: " 369 "0x%04x", MAC2STR(sta->addr), ht_capab); 370 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) { 371 if (!sta->no_ht_gf_set) { 372 sta->no_ht_gf_set = 1; 373 hapd->iface->num_sta_ht_no_gf++; 374 } 375 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num " 376 "of non-gf stations %d", 377 __func__, MAC2STR(sta->addr), 378 hapd->iface->num_sta_ht_no_gf); 379 } 380 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) { 381 if (!sta->ht_20mhz_set) { 382 sta->ht_20mhz_set = 1; 383 hapd->iface->num_sta_ht_20mhz++; 384 } 385 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of " 386 "20MHz HT STAs %d", 387 __func__, MAC2STR(sta->addr), 388 hapd->iface->num_sta_ht_20mhz); 389 } 390 391 if (ht_capab & HT_CAP_INFO_40MHZ_INTOLERANT) 392 ht40_intolerant_add(hapd->iface, sta); 393} 394 395 396static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta) 397{ 398 if (!sta->no_ht_set) { 399 sta->no_ht_set = 1; 400 hapd->iface->num_sta_no_ht++; 401 } 402 if (hapd->iconf->ieee80211n) { 403 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of " 404 "non-HT stations %d", 405 __func__, MAC2STR(sta->addr), 406 hapd->iface->num_sta_no_ht); 407 } 408} 409 410 411void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta) 412{ 413 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities) 414 update_sta_ht(hapd, sta); 415 else 416 update_sta_no_ht(hapd, sta); 417 418 if (hostapd_ht_operation_update(hapd->iface) > 0) 419 ieee802_11_set_beacons(hapd->iface); 420} 421 422 423void hostapd_get_ht_capab(struct hostapd_data *hapd, 424 struct ieee80211_ht_capabilities *ht_cap, 425 struct ieee80211_ht_capabilities *neg_ht_cap) 426{ 427 u16 cap; 428 429 if (ht_cap == NULL) 430 return; 431 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap)); 432 cap = le_to_host16(neg_ht_cap->ht_capabilities_info); 433 434 /* 435 * Mask out HT features we don't support, but don't overwrite 436 * non-symmetric features like STBC and SMPS. Just because 437 * we're not in dynamic SMPS mode the STA might still be. 438 */ 439 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK | 440 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK); 441 442 /* 443 * STBC needs to be handled specially 444 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps 445 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps 446 */ 447 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK)) 448 cap &= ~HT_CAP_INFO_TX_STBC; 449 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC)) 450 cap &= ~HT_CAP_INFO_RX_STBC_MASK; 451 452 neg_ht_cap->ht_capabilities_info = host_to_le16(cap); 453} 454 455 456void ap_ht2040_timeout(void *eloop_data, void *user_data) 457{ 458 struct hostapd_iface *iface = eloop_data; 459 460 wpa_printf(MSG_INFO, "Switching to 40 MHz operation"); 461 462 iface->conf->secondary_channel = iface->secondary_ch; 463 ieee802_11_set_beacons(iface); 464} 465