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
hostapd_eid_ht_capabilities(struct hostapd_data * hapd,u8 * eid)28 u8 * 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
hostapd_eid_ht_operation(struct hostapd_data * hapd,u8 * eid)57 u8 * 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 /*
87 op_mode
88 Set 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
91 Set to 1 (HT non-member protection) if there may be non-HT STAs
92 in both the primary and the secondary channel
93 Set to 2 if only HT STAs are associated in BSS,
94 however and at least one 20 MHz HT STA is associated
95 Set to 3 (HT mixed mode) when one or more non-HT STAs are associated
96 */
hostapd_ht_operation_update(struct hostapd_iface * iface)97 int 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
copy_sta_ht_capab(struct hostapd_data * hapd,struct sta_info * sta,const u8 * ht_capab,size_t ht_capab_len)157 u16 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
update_sta_ht(struct hostapd_data * hapd,struct sta_info * sta)185 static 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
update_sta_no_ht(struct hostapd_data * hapd,struct sta_info * sta)215 static 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
update_ht_state(struct hostapd_data * hapd,struct sta_info * sta)230 void 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
hostapd_get_ht_capab(struct hostapd_data * hapd,struct ieee80211_ht_capabilities * ht_cap,struct ieee80211_ht_capabilities * neg_ht_cap)242 void 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