ieee802_11_ht.c revision 7d5c8f257a74ac0d12828962a492e8b84ef83923
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 "common/ieee802_11_defs.h" 14#include "hostapd.h" 15#include "ap_config.h" 16#include "sta_info.h" 17#include "beacon.h" 18#include "ieee802_11.h" 19 20 21u8 * hostapd_eid_ht_capabilities(struct hostapd_data *hapd, u8 *eid) 22{ 23 struct ieee80211_ht_capabilities *cap; 24 u8 *pos = eid; 25 26 if (!hapd->iconf->ieee80211n || !hapd->iface->current_mode || 27 hapd->conf->disable_11n) 28 return eid; 29 30 *pos++ = WLAN_EID_HT_CAP; 31 *pos++ = sizeof(*cap); 32 33 cap = (struct ieee80211_ht_capabilities *) pos; 34 os_memset(cap, 0, sizeof(*cap)); 35 cap->ht_capabilities_info = host_to_le16(hapd->iconf->ht_capab); 36 cap->a_mpdu_params = hapd->iface->current_mode->a_mpdu_params; 37 os_memcpy(cap->supported_mcs_set, hapd->iface->current_mode->mcs_set, 38 16); 39 40 /* TODO: ht_extended_capabilities (now fully disabled) */ 41 /* TODO: tx_bf_capability_info (now fully disabled) */ 42 /* TODO: asel_capabilities (now fully disabled) */ 43 44 pos += sizeof(*cap); 45 46 if (hapd->iconf->obss_interval) { 47 struct ieee80211_obss_scan_parameters *scan_params; 48 49 *pos++ = WLAN_EID_OVERLAPPING_BSS_SCAN_PARAMS; 50 *pos++ = sizeof(*scan_params); 51 52 scan_params = (struct ieee80211_obss_scan_parameters *) pos; 53 os_memset(scan_params, 0, sizeof(*scan_params)); 54 scan_params->width_trigger_scan_interval = 55 host_to_le16(hapd->iconf->obss_interval); 56 57 /* TODO: Fill in more parameters (supplicant ignores them) */ 58 59 pos += sizeof(*scan_params); 60 } 61 62 return pos; 63} 64 65 66u8 * hostapd_eid_ht_operation(struct hostapd_data *hapd, u8 *eid) 67{ 68 struct ieee80211_ht_operation *oper; 69 u8 *pos = eid; 70 71 if (!hapd->iconf->ieee80211n || hapd->conf->disable_11n) 72 return eid; 73 74 *pos++ = WLAN_EID_HT_OPERATION; 75 *pos++ = sizeof(*oper); 76 77 oper = (struct ieee80211_ht_operation *) pos; 78 os_memset(oper, 0, sizeof(*oper)); 79 80 oper->control_chan = hapd->iconf->channel; 81 oper->operation_mode = host_to_le16(hapd->iface->ht_op_mode); 82 if (hapd->iconf->secondary_channel == 1) 83 oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE | 84 HT_INFO_HT_PARAM_REC_TRANS_CHNL_WIDTH; 85 if (hapd->iconf->secondary_channel == -1) 86 oper->ht_param |= HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW | 87 HT_INFO_HT_PARAM_REC_TRANS_CHNL_WIDTH; 88 89 pos += sizeof(*oper); 90 91 return pos; 92} 93 94 95/* 96op_mode 97Set to 0 (HT pure) under the followign conditions 98 - all STAs in the BSS are 20/40 MHz HT in 20/40 MHz BSS or 99 - all STAs in the BSS are 20 MHz HT in 20 MHz BSS 100Set to 1 (HT non-member protection) if there may be non-HT STAs 101 in both the primary and the secondary channel 102Set to 2 if only HT STAs are associated in BSS, 103 however and at least one 20 MHz HT STA is associated 104Set to 3 (HT mixed mode) when one or more non-HT STAs are associated 105*/ 106int hostapd_ht_operation_update(struct hostapd_iface *iface) 107{ 108 u16 cur_op_mode, new_op_mode; 109 int op_mode_changes = 0; 110 111 if (!iface->conf->ieee80211n || iface->conf->ht_op_mode_fixed) 112 return 0; 113 114 wpa_printf(MSG_DEBUG, "%s current operation mode=0x%X", 115 __func__, iface->ht_op_mode); 116 117 if (!(iface->ht_op_mode & HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT) 118 && iface->num_sta_ht_no_gf) { 119 iface->ht_op_mode |= 120 HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT; 121 op_mode_changes++; 122 } else if ((iface->ht_op_mode & 123 HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT) && 124 iface->num_sta_ht_no_gf == 0) { 125 iface->ht_op_mode &= 126 ~HT_INFO_OPERATION_MODE_NON_GF_DEVS_PRESENT; 127 op_mode_changes++; 128 } 129 130 if (!(iface->ht_op_mode & HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT) && 131 (iface->num_sta_no_ht || iface->olbc_ht)) { 132 iface->ht_op_mode |= HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT; 133 op_mode_changes++; 134 } else if ((iface->ht_op_mode & 135 HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT) && 136 (iface->num_sta_no_ht == 0 && !iface->olbc_ht)) { 137 iface->ht_op_mode &= 138 ~HT_INFO_OPERATION_MODE_NON_HT_STA_PRESENT; 139 op_mode_changes++; 140 } 141 142 if (iface->num_sta_no_ht) 143 new_op_mode = OP_MODE_MIXED; 144 else if (iface->conf->secondary_channel && iface->num_sta_ht_20mhz) 145 new_op_mode = OP_MODE_20MHZ_HT_STA_ASSOCED; 146 else if (iface->olbc_ht) 147 new_op_mode = OP_MODE_MAY_BE_LEGACY_STAS; 148 else 149 new_op_mode = OP_MODE_PURE; 150 151 cur_op_mode = iface->ht_op_mode & HT_INFO_OPERATION_MODE_OP_MODE_MASK; 152 if (cur_op_mode != new_op_mode) { 153 iface->ht_op_mode &= ~HT_INFO_OPERATION_MODE_OP_MODE_MASK; 154 iface->ht_op_mode |= new_op_mode; 155 op_mode_changes++; 156 } 157 158 wpa_printf(MSG_DEBUG, "%s new operation mode=0x%X changes=%d", 159 __func__, iface->ht_op_mode, op_mode_changes); 160 161 return op_mode_changes; 162} 163 164 165u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta, 166 const u8 *ht_capab, size_t ht_capab_len) 167{ 168 /* Disable HT caps for STAs associated to no-HT BSSes. */ 169 if (!ht_capab || 170 ht_capab_len < sizeof(struct ieee80211_ht_capabilities) || 171 hapd->conf->disable_11n) { 172 sta->flags &= ~WLAN_STA_HT; 173 os_free(sta->ht_capabilities); 174 sta->ht_capabilities = NULL; 175 return WLAN_STATUS_SUCCESS; 176 } 177 178 if (sta->ht_capabilities == NULL) { 179 sta->ht_capabilities = 180 os_zalloc(sizeof(struct ieee80211_ht_capabilities)); 181 if (sta->ht_capabilities == NULL) 182 return WLAN_STATUS_UNSPECIFIED_FAILURE; 183 } 184 185 sta->flags |= WLAN_STA_HT; 186 os_memcpy(sta->ht_capabilities, ht_capab, 187 sizeof(struct ieee80211_ht_capabilities)); 188 189 return WLAN_STATUS_SUCCESS; 190} 191 192 193static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta) 194{ 195 u16 ht_capab; 196 197 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info); 198 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: " 199 "0x%04x", MAC2STR(sta->addr), ht_capab); 200 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) { 201 if (!sta->no_ht_gf_set) { 202 sta->no_ht_gf_set = 1; 203 hapd->iface->num_sta_ht_no_gf++; 204 } 205 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num " 206 "of non-gf stations %d", 207 __func__, MAC2STR(sta->addr), 208 hapd->iface->num_sta_ht_no_gf); 209 } 210 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) { 211 if (!sta->ht_20mhz_set) { 212 sta->ht_20mhz_set = 1; 213 hapd->iface->num_sta_ht_20mhz++; 214 } 215 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of " 216 "20MHz HT STAs %d", 217 __func__, MAC2STR(sta->addr), 218 hapd->iface->num_sta_ht_20mhz); 219 } 220} 221 222 223static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta) 224{ 225 if (!sta->no_ht_set) { 226 sta->no_ht_set = 1; 227 hapd->iface->num_sta_no_ht++; 228 } 229 if (hapd->iconf->ieee80211n) { 230 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of " 231 "non-HT stations %d", 232 __func__, MAC2STR(sta->addr), 233 hapd->iface->num_sta_no_ht); 234 } 235} 236 237 238void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta) 239{ 240 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities) 241 update_sta_ht(hapd, sta); 242 else 243 update_sta_no_ht(hapd, sta); 244 245 if (hostapd_ht_operation_update(hapd->iface) > 0) 246 ieee802_11_set_beacons(hapd->iface); 247} 248 249 250void hostapd_get_ht_capab(struct hostapd_data *hapd, 251 struct ieee80211_ht_capabilities *ht_cap, 252 struct ieee80211_ht_capabilities *neg_ht_cap) 253{ 254 u16 cap; 255 256 if (ht_cap == NULL) 257 return; 258 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap)); 259 cap = le_to_host16(neg_ht_cap->ht_capabilities_info); 260 261 /* 262 * Mask out HT features we don't support, but don't overwrite 263 * non-symmetric features like STBC and SMPS. Just because 264 * we're not in dynamic SMPS mode the STA might still be. 265 */ 266 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK | 267 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK); 268 269 /* 270 * STBC needs to be handled specially 271 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps 272 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps 273 */ 274 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK)) 275 cap &= ~HT_CAP_INFO_TX_STBC; 276 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC)) 277 cap &= ~HT_CAP_INFO_RX_STBC_MASK; 278 279 neg_ht_cap->ht_capabilities_info = host_to_le16(cap); 280} 281