ieee802_11_ht.c revision 9d9e60286e05ae45025b672636490bd12586138d
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_ht40_allowed = 1; 213 int i; 214 const u8 *start = (const u8 *) mgmt; 215 const u8 *data = start + IEEE80211_HDRLEN + 2; 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 if (len < IEEE80211_HDRLEN + 2 + sizeof(*bc_ie)) 225 return; 226 227 bc_ie = (struct ieee80211_2040_bss_coex_ie *) data; 228 if (bc_ie->element_id != WLAN_EID_20_40_BSS_COEXISTENCE || 229 bc_ie->length < 1) { 230 wpa_printf(MSG_DEBUG, "Unexpected IE (%u,%u) in coex report", 231 bc_ie->element_id, bc_ie->length); 232 return; 233 } 234 if (len < IEEE80211_HDRLEN + 2 + 2 + bc_ie->length) 235 return; 236 data += 2 + bc_ie->length; 237 238 wpa_printf(MSG_DEBUG, "20/40 BSS Coexistence Information field: 0x%x", 239 bc_ie->coex_param); 240 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) { 241 hostapd_logger(hapd, mgmt->sa, 242 HOSTAPD_MODULE_IEEE80211, 243 HOSTAPD_LEVEL_DEBUG, 244 "20 MHz BSS width request bit is set in BSS coexistence information field"); 245 is_ht40_allowed = 0; 246 } 247 248 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) { 249 hostapd_logger(hapd, mgmt->sa, 250 HOSTAPD_MODULE_IEEE80211, 251 HOSTAPD_LEVEL_DEBUG, 252 "40 MHz intolerant bit is set in BSS coexistence information field"); 253 is_ht40_allowed = 0; 254 } 255 256 if (start + len - data >= 3 && 257 data[0] == WLAN_EID_20_40_BSS_INTOLERANT && data[1] >= 1) { 258 u8 ielen = data[1]; 259 260 if (ielen > start + len - data - 2) 261 return; 262 ic_report = (struct ieee80211_2040_intol_chan_report *) data; 263 wpa_printf(MSG_DEBUG, 264 "20/40 BSS Intolerant Channel Report: Operating Class %u", 265 ic_report->op_class); 266 267 /* Go through the channel report to find any BSS there in the 268 * affected channel range */ 269 for (i = 0; i < ielen - 1; i++) { 270 u8 chan = ic_report->variable[i]; 271 272 if (is_40_allowed(iface, chan)) 273 continue; 274 hostapd_logger(hapd, mgmt->sa, 275 HOSTAPD_MODULE_IEEE80211, 276 HOSTAPD_LEVEL_DEBUG, 277 "20_40_INTOLERANT channel %d reported", 278 chan); 279 is_ht40_allowed = 0; 280 } 281 } 282 wpa_printf(MSG_DEBUG, "is_ht40_allowed=%d num_sta_ht40_intolerant=%d", 283 is_ht40_allowed, iface->num_sta_ht40_intolerant); 284 285 if (!is_ht40_allowed && 286 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 287 if (iface->conf->secondary_channel) { 288 hostapd_logger(hapd, mgmt->sa, 289 HOSTAPD_MODULE_IEEE80211, 290 HOSTAPD_LEVEL_INFO, 291 "Switching to 20 MHz operation"); 292 iface->conf->secondary_channel = 0; 293 ieee802_11_set_beacons(iface); 294 } 295 if (!iface->num_sta_ht40_intolerant && 296 iface->conf->obss_interval) { 297 unsigned int delay_time; 298 delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR * 299 iface->conf->obss_interval; 300 eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface, 301 NULL); 302 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout, 303 hapd->iface, NULL); 304 wpa_printf(MSG_DEBUG, 305 "Reschedule HT 20/40 timeout to occur in %u seconds", 306 delay_time); 307 } 308 } 309} 310 311 312u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta, 313 const u8 *ht_capab) 314{ 315 /* 316 * Disable HT caps for STAs associated to no-HT BSSes, or for stations 317 * that did not specify a valid WMM IE in the (Re)Association Request 318 * frame. 319 */ 320 if (!ht_capab || 321 !(sta->flags & WLAN_STA_WMM) || hapd->conf->disable_11n) { 322 sta->flags &= ~WLAN_STA_HT; 323 os_free(sta->ht_capabilities); 324 sta->ht_capabilities = NULL; 325 return WLAN_STATUS_SUCCESS; 326 } 327 328 if (sta->ht_capabilities == NULL) { 329 sta->ht_capabilities = 330 os_zalloc(sizeof(struct ieee80211_ht_capabilities)); 331 if (sta->ht_capabilities == NULL) 332 return WLAN_STATUS_UNSPECIFIED_FAILURE; 333 } 334 335 sta->flags |= WLAN_STA_HT; 336 os_memcpy(sta->ht_capabilities, ht_capab, 337 sizeof(struct ieee80211_ht_capabilities)); 338 339 return WLAN_STATUS_SUCCESS; 340} 341 342 343void ht40_intolerant_add(struct hostapd_iface *iface, struct sta_info *sta) 344{ 345 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G) 346 return; 347 348 wpa_printf(MSG_INFO, "HT: Forty MHz Intolerant is set by STA " MACSTR 349 " in Association Request", MAC2STR(sta->addr)); 350 351 if (sta->ht40_intolerant_set) 352 return; 353 354 sta->ht40_intolerant_set = 1; 355 iface->num_sta_ht40_intolerant++; 356 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL); 357 358 if (iface->conf->secondary_channel && 359 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 360 iface->conf->secondary_channel = 0; 361 ieee802_11_set_beacons(iface); 362 } 363} 364 365 366void ht40_intolerant_remove(struct hostapd_iface *iface, struct sta_info *sta) 367{ 368 if (!sta->ht40_intolerant_set) 369 return; 370 371 sta->ht40_intolerant_set = 0; 372 iface->num_sta_ht40_intolerant--; 373 374 if (iface->num_sta_ht40_intolerant == 0 && 375 (iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) && 376 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 377 unsigned int delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR * 378 iface->conf->obss_interval; 379 wpa_printf(MSG_DEBUG, 380 "HT: Start 20->40 MHz transition timer (%d seconds)", 381 delay_time); 382 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL); 383 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout, 384 iface, NULL); 385 } 386} 387 388 389static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta) 390{ 391 u16 ht_capab; 392 393 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info); 394 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: " 395 "0x%04x", MAC2STR(sta->addr), ht_capab); 396 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) { 397 if (!sta->no_ht_gf_set) { 398 sta->no_ht_gf_set = 1; 399 hapd->iface->num_sta_ht_no_gf++; 400 } 401 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num " 402 "of non-gf stations %d", 403 __func__, MAC2STR(sta->addr), 404 hapd->iface->num_sta_ht_no_gf); 405 } 406 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) { 407 if (!sta->ht_20mhz_set) { 408 sta->ht_20mhz_set = 1; 409 hapd->iface->num_sta_ht_20mhz++; 410 } 411 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of " 412 "20MHz HT STAs %d", 413 __func__, MAC2STR(sta->addr), 414 hapd->iface->num_sta_ht_20mhz); 415 } 416 417 if (ht_capab & HT_CAP_INFO_40MHZ_INTOLERANT) 418 ht40_intolerant_add(hapd->iface, sta); 419} 420 421 422static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta) 423{ 424 if (!sta->no_ht_set) { 425 sta->no_ht_set = 1; 426 hapd->iface->num_sta_no_ht++; 427 } 428 if (hapd->iconf->ieee80211n) { 429 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of " 430 "non-HT stations %d", 431 __func__, MAC2STR(sta->addr), 432 hapd->iface->num_sta_no_ht); 433 } 434} 435 436 437void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta) 438{ 439 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities) 440 update_sta_ht(hapd, sta); 441 else 442 update_sta_no_ht(hapd, sta); 443 444 if (hostapd_ht_operation_update(hapd->iface) > 0) 445 ieee802_11_set_beacons(hapd->iface); 446} 447 448 449void hostapd_get_ht_capab(struct hostapd_data *hapd, 450 struct ieee80211_ht_capabilities *ht_cap, 451 struct ieee80211_ht_capabilities *neg_ht_cap) 452{ 453 u16 cap; 454 455 if (ht_cap == NULL) 456 return; 457 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap)); 458 cap = le_to_host16(neg_ht_cap->ht_capabilities_info); 459 460 /* 461 * Mask out HT features we don't support, but don't overwrite 462 * non-symmetric features like STBC and SMPS. Just because 463 * we're not in dynamic SMPS mode the STA might still be. 464 */ 465 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK | 466 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK); 467 468 /* 469 * STBC needs to be handled specially 470 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps 471 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps 472 */ 473 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK)) 474 cap &= ~HT_CAP_INFO_TX_STBC; 475 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC)) 476 cap &= ~HT_CAP_INFO_RX_STBC_MASK; 477 478 neg_ht_cap->ht_capabilities_info = host_to_le16(cap); 479} 480 481 482void ap_ht2040_timeout(void *eloop_data, void *user_data) 483{ 484 struct hostapd_iface *iface = eloop_data; 485 486 wpa_printf(MSG_INFO, "Switching to 40 MHz operation"); 487 488 iface->conf->secondary_channel = iface->secondary_ch; 489 ieee802_11_set_beacons(iface); 490} 491