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
240 hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
241 HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d",
242 mgmt->u.action.u.public_action.action);
243
244 if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET))
245 return;
246
247 if (len < IEEE80211_HDRLEN + 2 + sizeof(*bc_ie))
248 return;
249
250 bc_ie = (struct ieee80211_2040_bss_coex_ie *) data;
251 if (bc_ie->element_id != WLAN_EID_20_40_BSS_COEXISTENCE ||
252 bc_ie->length < 1) {
253 wpa_printf(MSG_DEBUG, "Unexpected IE (%u,%u) in coex report",
254 bc_ie->element_id, bc_ie->length);
255 return;
256 }
257 if (len < IEEE80211_HDRLEN + 2 + 2 + bc_ie->length)
258 return;
259 data += 2 + bc_ie->length;
260
261 wpa_printf(MSG_DEBUG, "20/40 BSS Coexistence Information field: 0x%x",
262 bc_ie->coex_param);
263 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) {
264 hostapd_logger(hapd, mgmt->sa,
265 HOSTAPD_MODULE_IEEE80211,
266 HOSTAPD_LEVEL_DEBUG,
267 "20 MHz BSS width request bit is set in BSS coexistence information field");
268 is_ht40_allowed = 0;
269 }
270
271 if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) {
272 hostapd_logger(hapd, mgmt->sa,
273 HOSTAPD_MODULE_IEEE80211,
274 HOSTAPD_LEVEL_DEBUG,
275 "40 MHz intolerant bit is set in BSS coexistence information field");
276 is_ht40_allowed = 0;
277 }
278
279 if (start + len - data >= 3 &&
280 data[0] == WLAN_EID_20_40_BSS_INTOLERANT && data[1] >= 1) {
281 u8 ielen = data[1];
282
283 if (ielen > start + len - data - 2)
284 return;
285 ic_report = (struct ieee80211_2040_intol_chan_report *) data;
286 wpa_printf(MSG_DEBUG,
287 "20/40 BSS Intolerant Channel Report: Operating Class %u",
288 ic_report->op_class);
289
290 /* Go through the channel report to find any BSS there in the
291 * affected channel range */
292 for (i = 0; i < ielen - 1; i++) {
293 u8 chan = ic_report->variable[i];
294
295 if (is_40_allowed(iface, chan))
296 continue;
297 hostapd_logger(hapd, mgmt->sa,
298 HOSTAPD_MODULE_IEEE80211,
299 HOSTAPD_LEVEL_DEBUG,
300 "20_40_INTOLERANT channel %d reported",
301 chan);
302 is_ht40_allowed = 0;
303 }
304 }
305 wpa_printf(MSG_DEBUG, "is_ht40_allowed=%d num_sta_ht40_intolerant=%d",
306 is_ht40_allowed, iface->num_sta_ht40_intolerant);
307
308 if (!is_ht40_allowed &&
309 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
310 if (iface->conf->secondary_channel) {
311 hostapd_logger(hapd, mgmt->sa,
312 HOSTAPD_MODULE_IEEE80211,
313 HOSTAPD_LEVEL_INFO,
314 "Switching to 20 MHz operation");
315 iface->conf->secondary_channel = 0;
316 ieee802_11_set_beacons(iface);
317 }
318 if (!iface->num_sta_ht40_intolerant &&
319 iface->conf->obss_interval) {
320 unsigned int delay_time;
321 delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *
322 iface->conf->obss_interval;
323 eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface,
324 NULL);
325 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,
326 hapd->iface, NULL);
327 wpa_printf(MSG_DEBUG,
328 "Reschedule HT 20/40 timeout to occur in %u seconds",
329 delay_time);
330 }
331 }
332 }
333
334
copy_sta_ht_capab(struct hostapd_data * hapd,struct sta_info * sta,const u8 * ht_capab)335 u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta,
336 const u8 *ht_capab)
337 {
338 /*
339 * Disable HT caps for STAs associated to no-HT BSSes, or for stations
340 * that did not specify a valid WMM IE in the (Re)Association Request
341 * frame.
342 */
343 if (!ht_capab || !(sta->flags & WLAN_STA_WMM) ||
344 !hapd->iconf->ieee80211n || hapd->conf->disable_11n) {
345 sta->flags &= ~WLAN_STA_HT;
346 os_free(sta->ht_capabilities);
347 sta->ht_capabilities = NULL;
348 return WLAN_STATUS_SUCCESS;
349 }
350
351 if (sta->ht_capabilities == NULL) {
352 sta->ht_capabilities =
353 os_zalloc(sizeof(struct ieee80211_ht_capabilities));
354 if (sta->ht_capabilities == NULL)
355 return WLAN_STATUS_UNSPECIFIED_FAILURE;
356 }
357
358 sta->flags |= WLAN_STA_HT;
359 os_memcpy(sta->ht_capabilities, ht_capab,
360 sizeof(struct ieee80211_ht_capabilities));
361
362 return WLAN_STATUS_SUCCESS;
363 }
364
365
ht40_intolerant_add(struct hostapd_iface * iface,struct sta_info * sta)366 void ht40_intolerant_add(struct hostapd_iface *iface, struct sta_info *sta)
367 {
368 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)
369 return;
370
371 wpa_printf(MSG_INFO, "HT: Forty MHz Intolerant is set by STA " MACSTR
372 " in Association Request", MAC2STR(sta->addr));
373
374 if (sta->ht40_intolerant_set)
375 return;
376
377 sta->ht40_intolerant_set = 1;
378 iface->num_sta_ht40_intolerant++;
379 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);
380
381 if (iface->conf->secondary_channel &&
382 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
383 iface->conf->secondary_channel = 0;
384 ieee802_11_set_beacons(iface);
385 }
386 }
387
388
ht40_intolerant_remove(struct hostapd_iface * iface,struct sta_info * sta)389 void ht40_intolerant_remove(struct hostapd_iface *iface, struct sta_info *sta)
390 {
391 if (!sta->ht40_intolerant_set)
392 return;
393
394 sta->ht40_intolerant_set = 0;
395 iface->num_sta_ht40_intolerant--;
396
397 if (iface->num_sta_ht40_intolerant == 0 &&
398 (iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&
399 (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
400 unsigned int delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *
401 iface->conf->obss_interval;
402 wpa_printf(MSG_DEBUG,
403 "HT: Start 20->40 MHz transition timer (%d seconds)",
404 delay_time);
405 eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);
406 eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,
407 iface, NULL);
408 }
409 }
410
411
update_sta_ht(struct hostapd_data * hapd,struct sta_info * sta)412 static void update_sta_ht(struct hostapd_data *hapd, struct sta_info *sta)
413 {
414 u16 ht_capab;
415
416 ht_capab = le_to_host16(sta->ht_capabilities->ht_capabilities_info);
417 wpa_printf(MSG_DEBUG, "HT: STA " MACSTR " HT Capabilities Info: "
418 "0x%04x", MAC2STR(sta->addr), ht_capab);
419 if ((ht_capab & HT_CAP_INFO_GREEN_FIELD) == 0) {
420 if (!sta->no_ht_gf_set) {
421 sta->no_ht_gf_set = 1;
422 hapd->iface->num_sta_ht_no_gf++;
423 }
424 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no greenfield, num "
425 "of non-gf stations %d",
426 __func__, MAC2STR(sta->addr),
427 hapd->iface->num_sta_ht_no_gf);
428 }
429 if ((ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) == 0) {
430 if (!sta->ht_20mhz_set) {
431 sta->ht_20mhz_set = 1;
432 hapd->iface->num_sta_ht_20mhz++;
433 }
434 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - 20 MHz HT, num of "
435 "20MHz HT STAs %d",
436 __func__, MAC2STR(sta->addr),
437 hapd->iface->num_sta_ht_20mhz);
438 }
439
440 if (ht_capab & HT_CAP_INFO_40MHZ_INTOLERANT)
441 ht40_intolerant_add(hapd->iface, sta);
442 }
443
444
update_sta_no_ht(struct hostapd_data * hapd,struct sta_info * sta)445 static void update_sta_no_ht(struct hostapd_data *hapd, struct sta_info *sta)
446 {
447 if (!sta->no_ht_set) {
448 sta->no_ht_set = 1;
449 hapd->iface->num_sta_no_ht++;
450 }
451 if (hapd->iconf->ieee80211n) {
452 wpa_printf(MSG_DEBUG, "%s STA " MACSTR " - no HT, num of "
453 "non-HT stations %d",
454 __func__, MAC2STR(sta->addr),
455 hapd->iface->num_sta_no_ht);
456 }
457 }
458
459
update_ht_state(struct hostapd_data * hapd,struct sta_info * sta)460 void update_ht_state(struct hostapd_data *hapd, struct sta_info *sta)
461 {
462 if ((sta->flags & WLAN_STA_HT) && sta->ht_capabilities)
463 update_sta_ht(hapd, sta);
464 else
465 update_sta_no_ht(hapd, sta);
466
467 if (hostapd_ht_operation_update(hapd->iface) > 0)
468 ieee802_11_set_beacons(hapd->iface);
469 }
470
471
hostapd_get_ht_capab(struct hostapd_data * hapd,struct ieee80211_ht_capabilities * ht_cap,struct ieee80211_ht_capabilities * neg_ht_cap)472 void hostapd_get_ht_capab(struct hostapd_data *hapd,
473 struct ieee80211_ht_capabilities *ht_cap,
474 struct ieee80211_ht_capabilities *neg_ht_cap)
475 {
476 u16 cap;
477
478 if (ht_cap == NULL)
479 return;
480 os_memcpy(neg_ht_cap, ht_cap, sizeof(*neg_ht_cap));
481 cap = le_to_host16(neg_ht_cap->ht_capabilities_info);
482
483 /*
484 * Mask out HT features we don't support, but don't overwrite
485 * non-symmetric features like STBC and SMPS. Just because
486 * we're not in dynamic SMPS mode the STA might still be.
487 */
488 cap &= (hapd->iconf->ht_capab | HT_CAP_INFO_RX_STBC_MASK |
489 HT_CAP_INFO_TX_STBC | HT_CAP_INFO_SMPS_MASK);
490
491 /*
492 * STBC needs to be handled specially
493 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps
494 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps
495 */
496 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_RX_STBC_MASK))
497 cap &= ~HT_CAP_INFO_TX_STBC;
498 if (!(hapd->iconf->ht_capab & HT_CAP_INFO_TX_STBC))
499 cap &= ~HT_CAP_INFO_RX_STBC_MASK;
500
501 neg_ht_cap->ht_capabilities_info = host_to_le16(cap);
502 }
503
504
ap_ht2040_timeout(void * eloop_data,void * user_data)505 void ap_ht2040_timeout(void *eloop_data, void *user_data)
506 {
507 struct hostapd_iface *iface = eloop_data;
508
509 wpa_printf(MSG_INFO, "Switching to 40 MHz operation");
510
511 iface->conf->secondary_channel = iface->secondary_ch;
512 ieee802_11_set_beacons(iface);
513 }
514