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
111 /*
112 op_mode
113 Set to 0 (HT pure) under the followign conditions
114 - all STAs in the BSS are 20/40 MHz HT in 20/40 MHz BSS or
115 - all STAs in the BSS are 20 MHz HT in 20 MHz BSS
116 Set to 1 (HT non-member protection) if there may be non-HT STAs
117 in both the primary and the secondary channel
118 Set to 2 if only HT STAs are associated in BSS,
119 however and at least one 20 MHz HT STA is associated
120 Set to 3 (HT mixed mode) when one or more non-HT STAs are associated
121 */
hostapd_ht_operation_update(struct hostapd_iface * iface)122 int hostapd_ht_operation_update(struct hostapd_iface *iface)
123 {
124 u16 cur_op_mode, new_op_mode;
125 int op_mode_changes = 0;
126
127 if (!iface->conf->ieee80211n || iface->conf->ht_op_mode_fixed)
128 return 0;
129
130 wpa_printf(MSG_DEBUG, "%s current operation mode=0x%X",
131 __func__, iface->ht_op_mode);
132
133 if (!(iface->ht_op_mode & HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT)
134 && iface->num_sta_ht_no_gf) {
135 iface->ht_op_mode |= HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT;
136 op_mode_changes++;
137 } else if ((iface->ht_op_mode &
138 HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT) &&
139 iface->num_sta_ht_no_gf == 0) {
140 iface->ht_op_mode &= ~HT_OPER_OP_MODE_NON_GF_HT_STAS_PRESENT;
141 op_mode_changes++;
142 }
143
144 if (!(iface->ht_op_mode & HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) &&
145 (iface->num_sta_no_ht || iface->olbc_ht)) {
146 iface->ht_op_mode |= HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT;
147 op_mode_changes++;
148 } else if ((iface->ht_op_mode &
149 HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT) &&
150 (iface->num_sta_no_ht == 0 && !iface->olbc_ht)) {
151 iface->ht_op_mode &= ~HT_OPER_OP_MODE_OBSS_NON_HT_STAS_PRESENT;
152 op_mode_changes++;
153 }
154
155 if (iface->num_sta_no_ht)
156 new_op_mode = HT_PROT_NON_HT_MIXED;
157 else if (iface->conf->secondary_channel && iface->num_sta_ht_20mhz)
158 new_op_mode = HT_PROT_20MHZ_PROTECTION;
159 else if (iface->olbc_ht)
160 new_op_mode = HT_PROT_NONMEMBER_PROTECTION;
161 else
162 new_op_mode = HT_PROT_NO_PROTECTION;
163
164 cur_op_mode = iface->ht_op_mode & HT_OPER_OP_MODE_HT_PROT_MASK;
165 if (cur_op_mode != new_op_mode) {
166 iface->ht_op_mode &= ~HT_OPER_OP_MODE_HT_PROT_MASK;
167 iface->ht_op_mode |= new_op_mode;
168 op_mode_changes++;
169 }
170
171 wpa_printf(MSG_DEBUG, "%s new operation mode=0x%X changes=%d",
172 __func__, iface->ht_op_mode, op_mode_changes);
173
174 return op_mode_changes;
175 }
176
177
is_40_allowed(struct hostapd_iface * iface,int channel)178 static int is_40_allowed(struct hostapd_iface *iface, int channel)
179 {
180 int pri_freq, sec_freq;
181 int affected_start, affected_end;
182 int pri = 2407 + 5 * channel;
183
184 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)
185 return 1;
186
187 pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);
188
189 if (iface->conf->secondary_channel > 0)
190 sec_freq = pri_freq + 20;
191 else
192 sec_freq = pri_freq - 20;
193
194 affected_start = (pri_freq + sec_freq) / 2 - 25;
195 affected_end = (pri_freq + sec_freq) / 2 + 25;
196 if ((pri < affected_start || pri > affected_end))
197 return 1; /* not within affected channel range */
198
199 wpa_printf(MSG_ERROR, "40 MHz affected channel range: [%d,%d] MHz",
200 affected_start, affected_end);
201 wpa_printf(MSG_ERROR, "Neighboring BSS: freq=%d", pri);
202 return 0;
203 }
204
205
hostapd_2040_coex_action(struct hostapd_data * hapd,const struct ieee80211_mgmt * mgmt,size_t len)206 void hostapd_2040_coex_action(struct hostapd_data *hapd,
207 const struct ieee80211_mgmt *mgmt, size_t len)
208 {
209 struct hostapd_iface *iface = hapd->iface;
210 struct ieee80211_2040_bss_coex_ie *bc_ie;
211 struct ieee80211_2040_intol_chan_report *ic_report;
212 int is_ht_allowed = 1;
213 int i;
214 const u8 *data = ((const u8 *) mgmt) + 1;
215
216 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
217 HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d",
218 mgmt->u.action.u.public_action.action);
219
220 if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET))
221 return;
222
223 if (len < IEEE80211_HDRLEN + 1)
224 return;
225 data++;
226
227 bc_ie = (struct ieee80211_2040_bss_coex_ie *) &data[0];
228 ic_report = (struct ieee80211_2040_intol_chan_report *)
229 (&data[0] + sizeof(*bc_ie));
230
231 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) {
232 hostapd_logger(hapd, mgmt->sa,
233 HOSTAPD_MODULE_IEEE80211,
234 HOSTAPD_LEVEL_DEBUG,
235 "20 MHz BSS width request bit is set in BSS coexistence information field");
236 is_ht_allowed = 0;
237 }
238
239 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) {
240 hostapd_logger(hapd, mgmt->sa,
241 HOSTAPD_MODULE_IEEE80211,
242 HOSTAPD_LEVEL_DEBUG,
243 "40 MHz intolerant bit is set in BSS coexistence information field");
244 is_ht_allowed = 0;
245 }
246
247 if (ic_report &&
248 (ic_report->element_id == WLAN_EID_20_40_BSS_INTOLERANT)) {
249 /* Go through the channel report to find any BSS there in the
250 * affected channel range */
251 for (i = 0; i < ic_report->length - 1; i++) {
252 if (is_40_allowed(iface, ic_report->variable[i]))
253 continue;
254 hostapd_logger(hapd, mgmt->sa,
255 HOSTAPD_MODULE_IEEE80211,
256 HOSTAPD_LEVEL_DEBUG,
257 "20_40_INTOLERANT channel %d reported",
258 ic_report->variable[i]);
259 is_ht_allowed = 0;
260 break;
261 }
262 }
263
264 if (!is_ht_allowed &&
265 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
266 if (iface->conf->secondary_channel) {
267 hostapd_logger(hapd, mgmt->sa,
268 HOSTAPD_MODULE_IEEE80211,
269 HOSTAPD_LEVEL_INFO,
270 "Switching to 20 MHz operation");
271 iface->conf->secondary_channel = 0;
272 ieee802_11_set_beacons(iface);
273 }
274 if (!iface->num_sta_ht40_intolerant) {
275 unsigned int delay_time;
276 delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *
277 iface->conf->obss_interval;
278 eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface,
279 NULL);
280 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,
281 hapd->iface, NULL);
282 }
283 }
284 }
285
286
copy_sta_ht_capab(struct hostapd_data * hapd,struct sta_info * sta,const u8 * ht_capab,size_t ht_capab_len)287 u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta,
288 const u8 *ht_capab, size_t ht_capab_len)
289 {
290 /* Disable HT caps for STAs associated to no-HT BSSes. */
291 if (!ht_capab ||
292 ht_capab_len < sizeof(struct ieee80211_ht_capabilities) ||
293 hapd->conf->disable_11n) {
294 sta->flags &= ~WLAN_STA_HT;
295 os_free(sta->ht_capabilities);
296 sta->ht_capabilities = NULL;
297 return WLAN_STATUS_SUCCESS;
298 }
299
300 if (sta->ht_capabilities == NULL) {
301 sta->ht_capabilities =
302 os_zalloc(sizeof(struct ieee80211_ht_capabilities));
303 if (sta->ht_capabilities == NULL)
304 return WLAN_STATUS_UNSPECIFIED_FAILURE;
305 }
306
307 sta->flags |= WLAN_STA_HT;
308 os_memcpy(sta->ht_capabilities, ht_capab,
309 sizeof(struct ieee80211_ht_capabilities));
310
311 return WLAN_STATUS_SUCCESS;
312 }
313
314
ht40_intolerant_add(struct hostapd_iface * iface,struct sta_info * sta)315 void ht40_intolerant_add(struct hostapd_iface *iface, struct sta_info *sta)
316 {
317 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)
318 return;
319
320 wpa_printf(MSG_INFO, "HT: Forty MHz Intolerant is set by STA " MACSTR
321 " in Association Request", MAC2STR(sta->addr));
322
323 if (sta->ht40_intolerant_set)
324 return;
325
326 sta->ht40_intolerant_set = 1;
327 iface->num_sta_ht40_intolerant++;
328 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);
329
330 if (iface->conf->secondary_channel &&
331 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
332 iface->conf->secondary_channel = 0;
333 ieee802_11_set_beacons(iface);
334 }
335 }
336
337
ht40_intolerant_remove(struct hostapd_iface * iface,struct sta_info * sta)338 void ht40_intolerant_remove(struct hostapd_iface *iface, struct sta_info *sta)
339 {
340 if (!sta->ht40_intolerant_set)
341 return;
342
343 sta->ht40_intolerant_set = 0;
344 iface->num_sta_ht40_intolerant--;
345
346 if (iface->num_sta_ht40_intolerant == 0 &&
347 (iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&
348 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
349 unsigned int delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *
350 iface->conf->obss_interval;
351 wpa_printf(MSG_DEBUG,
352 "HT: Start 20->40 MHz transition timer (%d seconds)",
353 delay_time);
354 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);
355 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,
356 iface, NULL);
357 }
358 }
359
360
update_sta_ht(struct hostapd_data * hapd,struct sta_info * sta)361 static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta)
362 {
363 u16 ht_capab;
364
365 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info);
366 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: "
367 "0x%04x", MAC2STR(sta->addr), ht_capab);
368 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) {
369 if (!sta->no_ht_gf_set) {
370 sta->no_ht_gf_set = 1;
371 hapd->iface->num_sta_ht_no_gf++;
372 }
373 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num "
374 "of non-gf stations %d",
375 __func__, MAC2STR(sta->addr),
376 hapd->iface->num_sta_ht_no_gf);
377 }
378 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) {
379 if (!sta->ht_20mhz_set) {
380 sta->ht_20mhz_set = 1;
381 hapd->iface->num_sta_ht_20mhz++;
382 }
383 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of "
384 "20MHz HT STAs %d",
385 __func__, MAC2STR(sta->addr),
386 hapd->iface->num_sta_ht_20mhz);
387 }
388
389 if (ht_capab & HT_CAP_INFO_40MHZ_INTOLERANT)
390 ht40_intolerant_add(hapd->iface, sta);
391 }
392
393
update_sta_no_ht(struct hostapd_data * hapd,struct sta_info * sta)394 static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta)
395 {
396 if (!sta->no_ht_set) {
397 sta->no_ht_set = 1;
398 hapd->iface->num_sta_no_ht++;
399 }
400 if (hapd->iconf->ieee80211n) {
401 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of "
402 "non-HT stations %d",
403 __func__, MAC2STR(sta->addr),
404 hapd->iface->num_sta_no_ht);
405 }
406 }
407
408
update_ht_state(struct hostapd_data * hapd,struct sta_info * sta)409 void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta)
410 {
411 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities)
412 update_sta_ht(hapd, sta);
413 else
414 update_sta_no_ht(hapd, sta);
415
416 if (hostapd_ht_operation_update(hapd->iface) > 0)
417 ieee802_11_set_beacons(hapd->iface);
418 }
419
420
hostapd_get_ht_capab(struct hostapd_data * hapd,struct ieee80211_ht_capabilities * ht_cap,struct ieee80211_ht_capabilities * neg_ht_cap)421 void hostapd_get_ht_capab(struct hostapd_data *hapd,
422 struct ieee80211_ht_capabilities *ht_cap,
423 struct ieee80211_ht_capabilities *neg_ht_cap)
424 {
425 u16 cap;
426
427 if (ht_cap == NULL)
428 return;
429 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap));
430 cap = le_to_host16(neg_ht_cap->ht_capabilities_info);
431
432 /*
433 * Mask out HT features we don't support, but don't overwrite
434 * non-symmetric features like STBC and SMPS. Just because
435 * we're not in dynamic SMPS mode the STA might still be.
436 */
437 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK |
438 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK);
439
440 /*
441 * STBC needs to be handled specially
442 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps
443 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps
444 */
445 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK))
446 cap &= ~HT_CAP_INFO_TX_STBC;
447 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC))
448 cap &= ~HT_CAP_INFO_RX_STBC_MASK;
449
450 neg_ht_cap->ht_capabilities_info = host_to_le16(cap);
451 }
452
453
ap_ht2040_timeout(void * eloop_data,void * user_data)454 void ap_ht2040_timeout(void *eloop_data, void *user_data)
455 {
456 struct hostapd_iface *iface = eloop_data;
457
458 wpa_printf(MSG_INFO, "Switching to 40 MHz operation");
459
460 iface->conf->secondary_channel = iface->secondary_ch;
461 ieee802_11_set_beacons(iface);
462 }
463