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 24 u8 * 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 82 u8 * 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 u8 * hostapd_eid_secondary_channel(struct hostapd_data *hapd, u8 *eid) 112 { 113 u8 sec_ch; 114 115 if (!hapd->cs_freq_params.channel || 116 !hapd->cs_freq_params.sec_channel_offset) 117 return eid; 118 119 if (hapd->cs_freq_params.sec_channel_offset == -1) 120 sec_ch = HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW; 121 else if (hapd->cs_freq_params.sec_channel_offset == 1) 122 sec_ch = HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE; 123 else 124 return eid; 125 126 *eid++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET; 127 *eid++ = 1; 128 *eid++ = sec_ch; 129 130 return eid; 131 } 132 133 134 /* 135 op_mode 136 Set to 0 (HT pure) under the followign conditions 137 - all STAs in the BSS are 20/40 MHz HT in 20/40 MHz BSS or 138 - all STAs in the BSS are 20 MHz HT in 20 MHz BSS 139 Set to 1 (HT non-member protection) if there may be non-HT STAs 140 in both the primary and the secondary channel 141 Set to 2 if only HT STAs are associated in BSS, 142 however and at least one 20 MHz HT STA is associated 143 Set to 3 (HT mixed mode) when one or more non-HT STAs are associated 144 */ 145 int hostapd_ht_operation_update(struct hostapd_iface *iface) 146 { 147 u16 cur_op_mode, new_op_mode; 148 int op_mode_changes = 0; 149 150 if (!iface->conf->ieee80211n || iface->conf->ht_op_mode_fixed) 151 return 0; 152 153 wpa_printf(MSG_DEBUG, "%s current operation mode=0x%X", 154 __func__, iface->ht_op_mode); 155 156 if (!(iface->ht_op_mode & HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT) 157 && iface->num_sta_ht_no_gf) { 158 iface->ht_op_mode |= HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT; 159 op_mode_changes++; 160 } else if ((iface->ht_op_mode & 161 HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT) && 162 iface->num_sta_ht_no_gf == 0) { 163 iface->ht_op_mode &= ~HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT; 164 op_mode_changes++; 165 } 166 167 if (!(iface->ht_op_mode & HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) && 168 (iface->num_sta_no_ht || iface->olbc_ht)) { 169 iface->ht_op_mode |= HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT; 170 op_mode_changes++; 171 } else if ((iface->ht_op_mode & 172 HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) && 173 (iface->num_sta_no_ht == 0 && !iface->olbc_ht)) { 174 iface->ht_op_mode &= ~HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT; 175 op_mode_changes++; 176 } 177 178 if (iface->num_sta_no_ht) 179 new_op_mode = HT_PROT_NON_HT_MIXED; 180 else if (iface->conf->secondary_channel && iface->num_sta_ht_20mhz) 181 new_op_mode = HT_PROT_20MHZ_PROTECTION; 182 else if (iface->olbc_ht) 183 new_op_mode = HT_PROT_NONMEMBER_PROTECTION; 184 else 185 new_op_mode = HT_PROT_NO_PROTECTION; 186 187 cur_op_mode = iface->ht_op_mode & HT_OPER_OP_MODE_HT_PROT_MASK; 188 if (cur_op_mode != new_op_mode) { 189 iface->ht_op_mode &= ~HT_OPER_OP_MODE_HT_PROT_MASK; 190 iface->ht_op_mode |= new_op_mode; 191 op_mode_changes++; 192 } 193 194 wpa_printf(MSG_DEBUG, "%s new operation mode=0x%X changes=%d", 195 __func__, iface->ht_op_mode, op_mode_changes); 196 197 return op_mode_changes; 198 } 199 200 201 static int is_40_allowed(struct hostapd_iface *iface, int channel) 202 { 203 int pri_freq, sec_freq; 204 int affected_start, affected_end; 205 int pri = 2407 + 5 * channel; 206 207 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G) 208 return 1; 209 210 pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel); 211 212 if (iface->conf->secondary_channel > 0) 213 sec_freq = pri_freq + 20; 214 else 215 sec_freq = pri_freq - 20; 216 217 affected_start = (pri_freq + sec_freq) / 2 - 25; 218 affected_end = (pri_freq + sec_freq) / 2 + 25; 219 if ((pri < affected_start || pri > affected_end)) 220 return 1; /* not within affected channel range */ 221 222 wpa_printf(MSG_ERROR, "40 MHz affected channel range: [%d,%d] MHz", 223 affected_start, affected_end); 224 wpa_printf(MSG_ERROR, "Neighboring BSS: freq=%d", pri); 225 return 0; 226 } 227 228 229 void hostapd_2040_coex_action(struct hostapd_data *hapd, 230 const struct ieee80211_mgmt *mgmt, size_t len) 231 { 232 struct hostapd_iface *iface = hapd->iface; 233 struct ieee80211_2040_bss_coex_ie *bc_ie; 234 struct ieee80211_2040_intol_chan_report *ic_report; 235 int is_ht40_allowed = 1; 236 int i; 237 const u8 *start = (const u8 *) mgmt; 238 const u8 *data = start + IEEE80211_HDRLEN + 2; 239 struct sta_info *sta; 240 241 wpa_printf(MSG_DEBUG, 242 "HT: Received 20/40 BSS Coexistence Management frame from " 243 MACSTR, MAC2STR(mgmt->sa)); 244 245 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211, 246 HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d", 247 mgmt->u.action.u.public_action.action); 248 249 if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) { 250 wpa_printf(MSG_DEBUG, 251 "Ignore 20/40 BSS Coexistence Management frame since 40 MHz capability is not enabled"); 252 return; 253 } 254 255 if (len < IEEE80211_HDRLEN + 2 + sizeof(*bc_ie)) { 256 wpa_printf(MSG_DEBUG, 257 "Ignore too short 20/40 BSS Coexistence Management frame"); 258 return; 259 } 260 261 /* 20/40 BSS Coexistence element */ 262 bc_ie = (struct ieee80211_2040_bss_coex_ie *) data; 263 if (bc_ie->element_id != WLAN_EID_20_40_BSS_COEXISTENCE || 264 bc_ie->length < 1) { 265 wpa_printf(MSG_DEBUG, "Unexpected IE (%u,%u) in coex report", 266 bc_ie->element_id, bc_ie->length); 267 return; 268 } 269 if (len < IEEE80211_HDRLEN + 2 + 2 + bc_ie->length) { 270 wpa_printf(MSG_DEBUG, 271 "Truncated 20/40 BSS Coexistence element"); 272 return; 273 } 274 data += 2 + bc_ie->length; 275 276 wpa_printf(MSG_DEBUG, 277 "20/40 BSS Coexistence Information field: 0x%x (%s%s%s%s%s%s)", 278 bc_ie->coex_param, 279 (bc_ie->coex_param & BIT(0)) ? "[InfoReq]" : "", 280 (bc_ie->coex_param & BIT(1)) ? "[40MHzIntolerant]" : "", 281 (bc_ie->coex_param & BIT(2)) ? "[20MHzBSSWidthReq]" : "", 282 (bc_ie->coex_param & BIT(3)) ? "[OBSSScanExemptionReq]" : "", 283 (bc_ie->coex_param & BIT(4)) ? 284 "[OBSSScanExemptionGrant]" : "", 285 (bc_ie->coex_param & (BIT(5) | BIT(6) | BIT(7))) ? 286 "[Reserved]" : ""); 287 288 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) { 289 /* Intra-BSS communication prohibiting 20/40 MHz BSS operation 290 */ 291 sta = ap_get_sta(hapd, mgmt->sa); 292 if (!sta || !(sta->flags & WLAN_STA_ASSOC)) { 293 wpa_printf(MSG_DEBUG, 294 "Ignore intra-BSS 20/40 BSS Coexistence Management frame from not-associated STA"); 295 return; 296 } 297 298 hostapd_logger(hapd, mgmt->sa, 299 HOSTAPD_MODULE_IEEE80211, 300 HOSTAPD_LEVEL_DEBUG, 301 "20 MHz BSS width request bit is set in BSS coexistence information field"); 302 is_ht40_allowed = 0; 303 } 304 305 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) { 306 /* Inter-BSS communication prohibiting 20/40 MHz BSS operation 307 */ 308 hostapd_logger(hapd, mgmt->sa, 309 HOSTAPD_MODULE_IEEE80211, 310 HOSTAPD_LEVEL_DEBUG, 311 "40 MHz intolerant bit is set in BSS coexistence information field"); 312 is_ht40_allowed = 0; 313 } 314 315 /* 20/40 BSS Intolerant Channel Report element (zero or more times) */ 316 while (start + len - data >= 3 && 317 data[0] == WLAN_EID_20_40_BSS_INTOLERANT && data[1] >= 1) { 318 u8 ielen = data[1]; 319 320 if (ielen > start + len - data - 2) { 321 wpa_printf(MSG_DEBUG, 322 "Truncated 20/40 BSS Intolerant Channel Report element"); 323 return; 324 } 325 ic_report = (struct ieee80211_2040_intol_chan_report *) data; 326 wpa_printf(MSG_DEBUG, 327 "20/40 BSS Intolerant Channel Report: Operating Class %u", 328 ic_report->op_class); 329 330 /* Go through the channel report to find any BSS there in the 331 * affected channel range */ 332 for (i = 0; i < ielen - 1; i++) { 333 u8 chan = ic_report->variable[i]; 334 335 if (chan == iface->conf->channel) 336 continue; /* matching own primary channel */ 337 if (is_40_allowed(iface, chan)) 338 continue; /* not within affected channels */ 339 hostapd_logger(hapd, mgmt->sa, 340 HOSTAPD_MODULE_IEEE80211, 341 HOSTAPD_LEVEL_DEBUG, 342 "20_40_INTOLERANT channel %d reported", 343 chan); 344 is_ht40_allowed = 0; 345 } 346 347 data += 2 + ielen; 348 } 349 wpa_printf(MSG_DEBUG, "is_ht40_allowed=%d num_sta_ht40_intolerant=%d", 350 is_ht40_allowed, iface->num_sta_ht40_intolerant); 351 352 if (!is_ht40_allowed && 353 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 354 if (iface->conf->secondary_channel) { 355 hostapd_logger(hapd, mgmt->sa, 356 HOSTAPD_MODULE_IEEE80211, 357 HOSTAPD_LEVEL_INFO, 358 "Switching to 20 MHz operation"); 359 iface->conf->secondary_channel = 0; 360 ieee802_11_set_beacons(iface); 361 } 362 if (!iface->num_sta_ht40_intolerant && 363 iface->conf->obss_interval) { 364 unsigned int delay_time; 365 delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR * 366 iface->conf->obss_interval; 367 eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface, 368 NULL); 369 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout, 370 hapd->iface, NULL); 371 wpa_printf(MSG_DEBUG, 372 "Reschedule HT 20/40 timeout to occur in %u seconds", 373 delay_time); 374 } 375 } 376 } 377 378 379 u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta, 380 const u8 *ht_capab) 381 { 382 /* 383 * Disable HT caps for STAs associated to no-HT BSSes, or for stations 384 * that did not specify a valid WMM IE in the (Re)Association Request 385 * frame. 386 */ 387 if (!ht_capab || !(sta->flags & WLAN_STA_WMM) || 388 !hapd->iconf->ieee80211n || hapd->conf->disable_11n) { 389 sta->flags &= ~WLAN_STA_HT; 390 os_free(sta->ht_capabilities); 391 sta->ht_capabilities = NULL; 392 return WLAN_STATUS_SUCCESS; 393 } 394 395 if (sta->ht_capabilities == NULL) { 396 sta->ht_capabilities = 397 os_zalloc(sizeof(struct ieee80211_ht_capabilities)); 398 if (sta->ht_capabilities == NULL) 399 return WLAN_STATUS_UNSPECIFIED_FAILURE; 400 } 401 402 sta->flags |= WLAN_STA_HT; 403 os_memcpy(sta->ht_capabilities, ht_capab, 404 sizeof(struct ieee80211_ht_capabilities)); 405 406 return WLAN_STATUS_SUCCESS; 407 } 408 409 410 void ht40_intolerant_add(struct hostapd_iface *iface, struct sta_info *sta) 411 { 412 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G) 413 return; 414 415 wpa_printf(MSG_INFO, "HT: Forty MHz Intolerant is set by STA " MACSTR 416 " in Association Request", MAC2STR(sta->addr)); 417 418 if (sta->ht40_intolerant_set) 419 return; 420 421 sta->ht40_intolerant_set = 1; 422 iface->num_sta_ht40_intolerant++; 423 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL); 424 425 if (iface->conf->secondary_channel && 426 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 427 iface->conf->secondary_channel = 0; 428 ieee802_11_set_beacons(iface); 429 } 430 } 431 432 433 void ht40_intolerant_remove(struct hostapd_iface *iface, struct sta_info *sta) 434 { 435 if (!sta->ht40_intolerant_set) 436 return; 437 438 sta->ht40_intolerant_set = 0; 439 iface->num_sta_ht40_intolerant--; 440 441 if (iface->num_sta_ht40_intolerant == 0 && 442 (iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) && 443 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) { 444 unsigned int delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR * 445 iface->conf->obss_interval; 446 wpa_printf(MSG_DEBUG, 447 "HT: Start 20->40 MHz transition timer (%d seconds)", 448 delay_time); 449 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL); 450 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout, 451 iface, NULL); 452 } 453 } 454 455 456 static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta) 457 { 458 u16 ht_capab; 459 460 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info); 461 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: " 462 "0x%04x", MAC2STR(sta->addr), ht_capab); 463 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) { 464 if (!sta->no_ht_gf_set) { 465 sta->no_ht_gf_set = 1; 466 hapd->iface->num_sta_ht_no_gf++; 467 } 468 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num " 469 "of non-gf stations %d", 470 __func__, MAC2STR(sta->addr), 471 hapd->iface->num_sta_ht_no_gf); 472 } 473 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) { 474 if (!sta->ht_20mhz_set) { 475 sta->ht_20mhz_set = 1; 476 hapd->iface->num_sta_ht_20mhz++; 477 } 478 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of " 479 "20MHz HT STAs %d", 480 __func__, MAC2STR(sta->addr), 481 hapd->iface->num_sta_ht_20mhz); 482 } 483 484 if (ht_capab & HT_CAP_INFO_40MHZ_INTOLERANT) 485 ht40_intolerant_add(hapd->iface, sta); 486 } 487 488 489 static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta) 490 { 491 if (!sta->no_ht_set) { 492 sta->no_ht_set = 1; 493 hapd->iface->num_sta_no_ht++; 494 } 495 if (hapd->iconf->ieee80211n) { 496 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of " 497 "non-HT stations %d", 498 __func__, MAC2STR(sta->addr), 499 hapd->iface->num_sta_no_ht); 500 } 501 } 502 503 504 void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta) 505 { 506 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities) 507 update_sta_ht(hapd, sta); 508 else 509 update_sta_no_ht(hapd, sta); 510 511 if (hostapd_ht_operation_update(hapd->iface) > 0) 512 ieee802_11_set_beacons(hapd->iface); 513 } 514 515 516 void hostapd_get_ht_capab(struct hostapd_data *hapd, 517 struct ieee80211_ht_capabilities *ht_cap, 518 struct ieee80211_ht_capabilities *neg_ht_cap) 519 { 520 u16 cap; 521 522 if (ht_cap == NULL) 523 return; 524 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap)); 525 cap = le_to_host16(neg_ht_cap->ht_capabilities_info); 526 527 /* 528 * Mask out HT features we don't support, but don't overwrite 529 * non-symmetric features like STBC and SMPS. Just because 530 * we're not in dynamic SMPS mode the STA might still be. 531 */ 532 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK | 533 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK); 534 535 /* 536 * STBC needs to be handled specially 537 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps 538 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps 539 */ 540 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK)) 541 cap &= ~HT_CAP_INFO_TX_STBC; 542 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC)) 543 cap &= ~HT_CAP_INFO_RX_STBC_MASK; 544 545 neg_ht_cap->ht_capabilities_info = host_to_le16(cap); 546 } 547 548 549 void ap_ht2040_timeout(void *eloop_data, void *user_data) 550 { 551 struct hostapd_iface *iface = eloop_data; 552 553 wpa_printf(MSG_INFO, "Switching to 40 MHz operation"); 554 555 iface->conf->secondary_channel = iface->secondary_ch; 556 ieee802_11_set_beacons(iface); 557 } 558