xref: /dragonfly/contrib/wpa_supplicant/src/ap/ieee802_11_ht.c (revision 3a84a4273475ed07d0ab1c2dfeffdfedef35d9cd)
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 
hostapd_eid_ht_capabilities(struct hostapd_data * hapd,u8 * eid)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 
hostapd_eid_ht_operation(struct hostapd_data * hapd,u8 * eid)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 
hostapd_eid_secondary_channel(struct hostapd_data * hapd,u8 * eid)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 */
hostapd_ht_operation_update(struct hostapd_iface * iface)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 
is_40_allowed(struct hostapd_iface * iface,int channel)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 
hostapd_2040_coex_action(struct hostapd_data * hapd,const struct ieee80211_mgmt * mgmt,size_t len)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 
copy_sta_ht_capab(struct hostapd_data * hapd,struct sta_info * sta,const u8 * ht_capab)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 
ht40_intolerant_add(struct hostapd_iface * iface,struct sta_info * sta)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 
ht40_intolerant_remove(struct hostapd_iface * iface,struct sta_info * sta)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 
update_sta_ht(struct hostapd_data * hapd,struct sta_info * sta)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 
update_sta_no_ht(struct hostapd_data * hapd,struct sta_info * sta)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 
update_ht_state(struct hostapd_data * hapd,struct sta_info * sta)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 
hostapd_get_ht_capab(struct hostapd_data * hapd,struct ieee80211_ht_capabilities * ht_cap,struct ieee80211_ht_capabilities * neg_ht_cap)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 
ap_ht2040_timeout(void * eloop_data,void * user_data)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