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_ht40_allowed = 1;
213 int i;
214 const u8 *start = (const u8 *) mgmt;
215 const u8 *data = start + IEEE80211_HDRLEN + 2;
216
217 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
218 HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d",
219 mgmt->u.action.u.public_action.action);
220
221 if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET))
222 return;
223
224 if (len < IEEE80211_HDRLEN + 2 + sizeof(*bc_ie))
225 return;
226
227 bc_ie = (struct ieee80211_2040_bss_coex_ie *) data;
228 if (bc_ie->element_id != WLAN_EID_20_40_BSS_COEXISTENCE ||
229 bc_ie->length < 1) {
230 wpa_printf(MSG_DEBUG, "Unexpected IE (%u,%u) in coex report",
231 bc_ie->element_id, bc_ie->length);
232 return;
233 }
234 if (len < IEEE80211_HDRLEN + 2 + 2 + bc_ie->length)
235 return;
236 data += 2 + bc_ie->length;
237
238 wpa_printf(MSG_DEBUG, "20/40 BSS Coexistence Information field: 0x%x",
239 bc_ie->coex_param);
240 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) {
241 hostapd_logger(hapd, mgmt->sa,
242 HOSTAPD_MODULE_IEEE80211,
243 HOSTAPD_LEVEL_DEBUG,
244 "20 MHz BSS width request bit is set in BSS coexistence information field");
245 is_ht40_allowed = 0;
246 }
247
248 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) {
249 hostapd_logger(hapd, mgmt->sa,
250 HOSTAPD_MODULE_IEEE80211,
251 HOSTAPD_LEVEL_DEBUG,
252 "40 MHz intolerant bit is set in BSS coexistence information field");
253 is_ht40_allowed = 0;
254 }
255
256 if (start + len - data >= 3 &&
257 data[0] == WLAN_EID_20_40_BSS_INTOLERANT && data[1] >= 1) {
258 u8 ielen = data[1];
259
260 if (ielen > start + len - data - 2)
261 return;
262 ic_report = (struct ieee80211_2040_intol_chan_report *) data;
263 wpa_printf(MSG_DEBUG,
264 "20/40 BSS Intolerant Channel Report: Operating Class %u",
265 ic_report->op_class);
266
267 /* Go through the channel report to find any BSS there in the
268 * affected channel range */
269 for (i = 0; i < ielen - 1; i++) {
270 u8 chan = ic_report->variable[i];
271
272 if (is_40_allowed(iface, chan))
273 continue;
274 hostapd_logger(hapd, mgmt->sa,
275 HOSTAPD_MODULE_IEEE80211,
276 HOSTAPD_LEVEL_DEBUG,
277 "20_40_INTOLERANT channel %d reported",
278 chan);
279 is_ht40_allowed = 0;
280 }
281 }
282 wpa_printf(MSG_DEBUG, "is_ht40_allowed=%d num_sta_ht40_intolerant=%d",
283 is_ht40_allowed, iface->num_sta_ht40_intolerant);
284
285 if (!is_ht40_allowed &&
286 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
287 if (iface->conf->secondary_channel) {
288 hostapd_logger(hapd, mgmt->sa,
289 HOSTAPD_MODULE_IEEE80211,
290 HOSTAPD_LEVEL_INFO,
291 "Switching to 20 MHz operation");
292 iface->conf->secondary_channel = 0;
293 ieee802_11_set_beacons(iface);
294 }
295 if (!iface->num_sta_ht40_intolerant &&
296 iface->conf->obss_interval) {
297 unsigned int delay_time;
298 delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *
299 iface->conf->obss_interval;
300 eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface,
301 NULL);
302 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,
303 hapd->iface, NULL);
304 wpa_printf(MSG_DEBUG,
305 "Reschedule HT 20/40 timeout to occur in %u seconds",
306 delay_time);
307 }
308 }
309 }
310
311
copy_sta_ht_capab(struct hostapd_data * hapd,struct sta_info * sta,const u8 * ht_capab)312 u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta,
313 const u8 *ht_capab)
314 {
315 /*
316 * Disable HT caps for STAs associated to no-HT BSSes, or for stations
317 * that did not specify a valid WMM IE in the (Re)Association Request
318 * frame.
319 */
320 if (!ht_capab ||
321 !(sta->flags & WLAN_STA_WMM) || hapd->conf->disable_11n) {
322 sta->flags &= ~WLAN_STA_HT;
323 os_free(sta->ht_capabilities);
324 sta->ht_capabilities = NULL;
325 return WLAN_STATUS_SUCCESS;
326 }
327
328 if (sta->ht_capabilities == NULL) {
329 sta->ht_capabilities =
330 os_zalloc(sizeof(struct ieee80211_ht_capabilities));
331 if (sta->ht_capabilities == NULL)
332 return WLAN_STATUS_UNSPECIFIED_FAILURE;
333 }
334
335 sta->flags |= WLAN_STA_HT;
336 os_memcpy(sta->ht_capabilities, ht_capab,
337 sizeof(struct ieee80211_ht_capabilities));
338
339 return WLAN_STATUS_SUCCESS;
340 }
341
342
ht40_intolerant_add(struct hostapd_iface * iface,struct sta_info * sta)343 void ht40_intolerant_add(struct hostapd_iface *iface, struct sta_info *sta)
344 {
345 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)
346 return;
347
348 wpa_printf(MSG_INFO, "HT: Forty MHz Intolerant is set by STA " MACSTR
349 " in Association Request", MAC2STR(sta->addr));
350
351 if (sta->ht40_intolerant_set)
352 return;
353
354 sta->ht40_intolerant_set = 1;
355 iface->num_sta_ht40_intolerant++;
356 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);
357
358 if (iface->conf->secondary_channel &&
359 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
360 iface->conf->secondary_channel = 0;
361 ieee802_11_set_beacons(iface);
362 }
363 }
364
365
ht40_intolerant_remove(struct hostapd_iface * iface,struct sta_info * sta)366 void ht40_intolerant_remove(struct hostapd_iface *iface, struct sta_info *sta)
367 {
368 if (!sta->ht40_intolerant_set)
369 return;
370
371 sta->ht40_intolerant_set = 0;
372 iface->num_sta_ht40_intolerant--;
373
374 if (iface->num_sta_ht40_intolerant == 0 &&
375 (iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&
376 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
377 unsigned int delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *
378 iface->conf->obss_interval;
379 wpa_printf(MSG_DEBUG,
380 "HT: Start 20->40 MHz transition timer (%d seconds)",
381 delay_time);
382 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);
383 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,
384 iface, NULL);
385 }
386 }
387
388
update_sta_ht(struct hostapd_data * hapd,struct sta_info * sta)389 static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta)
390 {
391 u16 ht_capab;
392
393 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info);
394 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: "
395 "0x%04x", MAC2STR(sta->addr), ht_capab);
396 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) {
397 if (!sta->no_ht_gf_set) {
398 sta->no_ht_gf_set = 1;
399 hapd->iface->num_sta_ht_no_gf++;
400 }
401 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num "
402 "of non-gf stations %d",
403 __func__, MAC2STR(sta->addr),
404 hapd->iface->num_sta_ht_no_gf);
405 }
406 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) {
407 if (!sta->ht_20mhz_set) {
408 sta->ht_20mhz_set = 1;
409 hapd->iface->num_sta_ht_20mhz++;
410 }
411 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of "
412 "20MHz HT STAs %d",
413 __func__, MAC2STR(sta->addr),
414 hapd->iface->num_sta_ht_20mhz);
415 }
416
417 if (ht_capab & HT_CAP_INFO_40MHZ_INTOLERANT)
418 ht40_intolerant_add(hapd->iface, sta);
419 }
420
421
update_sta_no_ht(struct hostapd_data * hapd,struct sta_info * sta)422 static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta)
423 {
424 if (!sta->no_ht_set) {
425 sta->no_ht_set = 1;
426 hapd->iface->num_sta_no_ht++;
427 }
428 if (hapd->iconf->ieee80211n) {
429 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of "
430 "non-HT stations %d",
431 __func__, MAC2STR(sta->addr),
432 hapd->iface->num_sta_no_ht);
433 }
434 }
435
436
update_ht_state(struct hostapd_data * hapd,struct sta_info * sta)437 void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta)
438 {
439 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities)
440 update_sta_ht(hapd, sta);
441 else
442 update_sta_no_ht(hapd, sta);
443
444 if (hostapd_ht_operation_update(hapd->iface) > 0)
445 ieee802_11_set_beacons(hapd->iface);
446 }
447
448
hostapd_get_ht_capab(struct hostapd_data * hapd,struct ieee80211_ht_capabilities * ht_cap,struct ieee80211_ht_capabilities * neg_ht_cap)449 void hostapd_get_ht_capab(struct hostapd_data *hapd,
450 struct ieee80211_ht_capabilities *ht_cap,
451 struct ieee80211_ht_capabilities *neg_ht_cap)
452 {
453 u16 cap;
454
455 if (ht_cap == NULL)
456 return;
457 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap));
458 cap = le_to_host16(neg_ht_cap->ht_capabilities_info);
459
460 /*
461 * Mask out HT features we don't support, but don't overwrite
462 * non-symmetric features like STBC and SMPS. Just because
463 * we're not in dynamic SMPS mode the STA might still be.
464 */
465 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK |
466 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK);
467
468 /*
469 * STBC needs to be handled specially
470 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps
471 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps
472 */
473 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK))
474 cap &= ~HT_CAP_INFO_TX_STBC;
475 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC))
476 cap &= ~HT_CAP_INFO_RX_STBC_MASK;
477
478 neg_ht_cap->ht_capabilities_info = host_to_le16(cap);
479 }
480
481
ap_ht2040_timeout(void * eloop_data,void * user_data)482 void ap_ht2040_timeout(void *eloop_data, void *user_data)
483 {
484 struct hostapd_iface *iface = eloop_data;
485
486 wpa_printf(MSG_INFO, "Switching to 40 MHz operation");
487
488 iface->conf->secondary_channel = iface->secondary_ch;
489 ieee802_11_set_beacons(iface);
490 }
491