ieee802_11_ht.c revision f86232838cf712377867cb42417c1613ab5dc425
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 program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 * Alternatively, this software may be distributed under the terms of BSD 11 * license. 12 * 13 * See README and COPYING for more details. 14 */ 15 16#include "utils/includes.h" 17 18#include "utils/common.h" 19#include "common/ieee802_11_defs.h" 20#include "drivers/driver.h" 21#include "hostapd.h" 22#include "ap_config.h" 23#include "sta_info.h" 24#include "beacon.h" 25#include "ieee802_11.h" 26 27 28u8 * hostapd_eid_ht_capabilities(struct hostapd_data *hapd, u8 *eid) 29{ 30 struct ieee80211_ht_capabilities *cap; 31 u8 *pos = eid; 32 33 if (!hapd->iconf->ieee80211n || !hapd->iface->current_mode || 34 hapd->conf->disable_11n) 35 return eid; 36 37 *pos++ = WLAN_EID_HT_CAP; 38 *pos++ = sizeof(*cap); 39 40 cap = (struct ieee80211_ht_capabilities *) pos; 41 os_memset(cap, 0, sizeof(*cap)); 42 cap->ht_capabilities_info = host_to_le16(hapd->iconf->ht_capab); 43 cap->a_mpdu_params = hapd->iface->current_mode->a_mpdu_params; 44 os_memcpy(cap->supported_mcs_set, hapd->iface->current_mode->mcs_set, 45 16); 46 47 /* TODO: ht_extended_capabilities (now fully disabled) */ 48 /* TODO: tx_bf_capability_info (now fully disabled) */ 49 /* TODO: asel_capabilities (now fully disabled) */ 50 51 pos += sizeof(*cap); 52 53 return pos; 54} 55 56 57u8 * hostapd_eid_ht_operation(struct hostapd_data *hapd, u8 *eid) 58{ 59 struct ieee80211_ht_operation *oper; 60 u8 *pos = eid; 61 62 if (!hapd->iconf->ieee80211n || hapd->conf->disable_11n) 63 return eid; 64 65 *pos++ = WLAN_EID_HT_OPERATION; 66 *pos++ = sizeof(*oper); 67 68 oper = (struct ieee80211_ht_operation *) pos; 69 os_memset(oper, 0, sizeof(*oper)); 70 71 oper->control_chan = hapd->iconf->channel; 72 oper->operation_mode = host_to_le16(hapd->iface->ht_op_mode); 73 if (hapd->iconf->secondary_channel == 1) 74 oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE | 75 HT_INFO_HT_PARAM_REC_TRANS_CHNL_WIDTH; 76 if (hapd->iconf->secondary_channel == -1) 77 oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW | 78 HT_INFO_HT_PARAM_REC_TRANS_CHNL_WIDTH; 79 80 pos += sizeof(*oper); 81 82 return pos; 83} 84 85 86/* 87op_mode 88Set to 0 (HT pure) under the followign conditions 89 - all STAs in the BSS are 20/40 MHz HT in 20/40 MHz BSS or 90 - all STAs in the BSS are 20 MHz HT in 20 MHz BSS 91Set to 1 (HT non-member protection) if there may be non-HT STAs 92 in both the primary and the secondary channel 93Set to 2 if only HT STAs are associated in BSS, 94 however and at least one 20 MHz HT STA is associated 95Set to 3 (HT mixed mode) when one or more non-HT STAs are associated 96*/ 97int hostapd_ht_operation_update(struct hostapd_iface *iface) 98{ 99 u16 cur_op_mode, new_op_mode; 100 int op_mode_changes = 0; 101 102 if (!iface->conf->ieee80211n || iface->conf->ht_op_mode_fixed) 103 return 0; 104 105 wpa_printf(MSG_DEBUG, "%s current operation mode=0x%X", 106 __func__, iface->ht_op_mode); 107 108 if (!(iface->ht_op_mode & HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT) 109 && iface->num_sta_ht_no_gf) { 110 iface->ht_op_mode |= 111 HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT; 112 op_mode_changes++; 113 } else if ((iface->ht_op_mode & 114 HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT) && 115 iface->num_sta_ht_no_gf == 0) { 116 iface->ht_op_mode &= 117 ~HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT; 118 op_mode_changes++; 119 } 120 121 if (!(iface->ht_op_mode & HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT) && 122 (iface->num_sta_no_ht || iface->olbc_ht)) { 123 iface->ht_op_mode |= HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT; 124 op_mode_changes++; 125 } else if ((iface->ht_op_mode & 126 HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT) && 127 (iface->num_sta_no_ht == 0 && !iface->olbc_ht)) { 128 iface->ht_op_mode &= 129 ~HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT; 130 op_mode_changes++; 131 } 132 133 new_op_mode = 0; 134 if (iface->num_sta_no_ht) 135 new_op_mode = OP_MODE_MIXED; 136 else if (iface->conf->secondary_channel && iface->num_sta_ht_20mhz) 137 new_op_mode = OP_MODE_20MHZ_HT_STA_ASSOCED; 138 else if (iface->olbc_ht) 139 new_op_mode = OP_MODE_MAY_BE_LEGACY_STAS; 140 else 141 new_op_mode = OP_MODE_PURE; 142 143 cur_op_mode = iface->ht_op_mode & HT_INFO_OPERATION_MODE_OP_MODE_MASK; 144 if (cur_op_mode != new_op_mode) { 145 iface->ht_op_mode &= ~HT_INFO_OPERATION_MODE_OP_MODE_MASK; 146 iface->ht_op_mode |= new_op_mode; 147 op_mode_changes++; 148 } 149 150 wpa_printf(MSG_DEBUG, "%s new operation mode=0x%X changes=%d", 151 __func__, iface->ht_op_mode, op_mode_changes); 152 153 return op_mode_changes; 154} 155 156 157u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta, 158 const u8 *ht_capab, size_t ht_capab_len) 159{ 160 /* Disable HT caps for STAs associated to no-HT BSSes. */ 161 if (!ht_capab || 162 ht_capab_len < sizeof(struct ieee80211_ht_capabilities) || 163 hapd->conf->disable_11n) { 164 sta->flags &= ~WLAN_STA_HT; 165 os_free(sta->ht_capabilities); 166 sta->ht_capabilities = NULL; 167 return WLAN_STATUS_SUCCESS; 168 } 169 170 if (sta->ht_capabilities == NULL) { 171 sta->ht_capabilities = 172 os_zalloc(sizeof(struct ieee80211_ht_capabilities)); 173 if (sta->ht_capabilities == NULL) 174 return WLAN_STATUS_UNSPECIFIED_FAILURE; 175 } 176 177 sta->flags |= WLAN_STA_HT; 178 os_memcpy(sta->ht_capabilities, ht_capab, 179 sizeof(struct ieee80211_ht_capabilities)); 180 181 return WLAN_STATUS_SUCCESS; 182} 183 184 185static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta) 186{ 187 u16 ht_capab; 188 189 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info); 190 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: " 191 "0x%04x", MAC2STR(sta->addr), ht_capab); 192 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) { 193 if (!sta->no_ht_gf_set) { 194 sta->no_ht_gf_set = 1; 195 hapd->iface->num_sta_ht_no_gf++; 196 } 197 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num " 198 "of non-gf stations %d", 199 __func__, MAC2STR(sta->addr), 200 hapd->iface->num_sta_ht_no_gf); 201 } 202 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) { 203 if (!sta->ht_20mhz_set) { 204 sta->ht_20mhz_set = 1; 205 hapd->iface->num_sta_ht_20mhz++; 206 } 207 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of " 208 "20MHz HT STAs %d", 209 __func__, MAC2STR(sta->addr), 210 hapd->iface->num_sta_ht_20mhz); 211 } 212} 213 214 215static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta) 216{ 217 if (!sta->no_ht_set) { 218 sta->no_ht_set = 1; 219 hapd->iface->num_sta_no_ht++; 220 } 221 if (hapd->iconf->ieee80211n) { 222 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of " 223 "non-HT stations %d", 224 __func__, MAC2STR(sta->addr), 225 hapd->iface->num_sta_no_ht); 226 } 227} 228 229 230void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta) 231{ 232 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities) 233 update_sta_ht(hapd, sta); 234 else 235 update_sta_no_ht(hapd, sta); 236 237 if (hostapd_ht_operation_update(hapd->iface) > 0) 238 ieee802_11_set_beacons(hapd->iface); 239} 240 241 242void hostapd_get_ht_capab(struct hostapd_data *hapd, 243 struct ieee80211_ht_capabilities *ht_cap, 244 struct ieee80211_ht_capabilities *neg_ht_cap) 245{ 246 u16 cap; 247 248 if (ht_cap == NULL) 249 return; 250 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap)); 251 cap = le_to_host16(neg_ht_cap->ht_capabilities_info); 252 253 /* 254 * Mask out HT features we don't support, but don't overwrite 255 * non-symmetric features like STBC and SMPS. Just because 256 * we're not in dynamic SMPS mode the STA might still be. 257 */ 258 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK | 259 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK); 260 261 /* 262 * STBC needs to be handled specially 263 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps 264 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps 265 */ 266 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK)) 267 cap &= ~HT_CAP_INFO_TX_STBC; 268 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC)) 269 cap &= ~HT_CAP_INFO_RX_STBC_MASK; 270 271 neg_ht_cap->ht_capabilities_info = host_to_le16(cap); 272} 273