xref: /freebsd/contrib/wpa/src/ap/hw_features.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /*
2  * hostapd / Hardware feature query and different modes
3  * Copyright 2002-2003, Instant802 Networks, Inc.
4  * Copyright 2005-2006, Devicescape Software, Inc.
5  * Copyright (c) 2008-2012, Jouni Malinen <j@w1.fi>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * Alternatively, this software may be distributed under the terms of BSD
12  * license.
13  *
14  * See README and COPYING for more details.
15  */
16 
17 #include "utils/includes.h"
18 
19 #include "utils/common.h"
20 #include "utils/eloop.h"
21 #include "common/ieee802_11_defs.h"
22 #include "common/ieee802_11_common.h"
23 #include "drivers/driver.h"
24 #include "hostapd.h"
25 #include "ap_config.h"
26 #include "ap_drv_ops.h"
27 #include "hw_features.h"
28 
29 
30 void hostapd_free_hw_features(struct hostapd_hw_modes *hw_features,
31 			      size_t num_hw_features)
32 {
33 	size_t i;
34 
35 	if (hw_features == NULL)
36 		return;
37 
38 	for (i = 0; i < num_hw_features; i++) {
39 		os_free(hw_features[i].channels);
40 		os_free(hw_features[i].rates);
41 	}
42 
43 	os_free(hw_features);
44 }
45 
46 
47 int hostapd_get_hw_features(struct hostapd_iface *iface)
48 {
49 	struct hostapd_data *hapd = iface->bss[0];
50 	int ret = 0, i, j;
51 	u16 num_modes, flags;
52 	struct hostapd_hw_modes *modes;
53 
54 	if (hostapd_drv_none(hapd))
55 		return -1;
56 	modes = hostapd_get_hw_feature_data(hapd, &num_modes, &flags);
57 	if (modes == NULL) {
58 		hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
59 			       HOSTAPD_LEVEL_DEBUG,
60 			       "Fetching hardware channel/rate support not "
61 			       "supported.");
62 		return -1;
63 	}
64 
65 	iface->hw_flags = flags;
66 
67 	hostapd_free_hw_features(iface->hw_features, iface->num_hw_features);
68 	iface->hw_features = modes;
69 	iface->num_hw_features = num_modes;
70 
71 	for (i = 0; i < num_modes; i++) {
72 		struct hostapd_hw_modes *feature = &modes[i];
73 		/* set flag for channels we can use in current regulatory
74 		 * domain */
75 		for (j = 0; j < feature->num_channels; j++) {
76 			/*
77 			 * Disable all channels that are marked not to allow
78 			 * IBSS operation or active scanning. In addition,
79 			 * disable all channels that require radar detection,
80 			 * since that (in addition to full DFS) is not yet
81 			 * supported.
82 			 */
83 			if (feature->channels[j].flag &
84 			    (HOSTAPD_CHAN_NO_IBSS |
85 			     HOSTAPD_CHAN_PASSIVE_SCAN |
86 			     HOSTAPD_CHAN_RADAR))
87 				feature->channels[j].flag |=
88 					HOSTAPD_CHAN_DISABLED;
89 			if (feature->channels[j].flag & HOSTAPD_CHAN_DISABLED)
90 				continue;
91 			wpa_printf(MSG_MSGDUMP, "Allowed channel: mode=%d "
92 				   "chan=%d freq=%d MHz max_tx_power=%d dBm",
93 				   feature->mode,
94 				   feature->channels[j].chan,
95 				   feature->channels[j].freq,
96 				   feature->channels[j].max_tx_power);
97 		}
98 	}
99 
100 	return ret;
101 }
102 
103 
104 int hostapd_prepare_rates(struct hostapd_iface *iface,
105 			  struct hostapd_hw_modes *mode)
106 {
107 	int i, num_basic_rates = 0;
108 	int basic_rates_a[] = { 60, 120, 240, -1 };
109 	int basic_rates_b[] = { 10, 20, -1 };
110 	int basic_rates_g[] = { 10, 20, 55, 110, -1 };
111 	int *basic_rates;
112 
113 	if (iface->conf->basic_rates)
114 		basic_rates = iface->conf->basic_rates;
115 	else switch (mode->mode) {
116 	case HOSTAPD_MODE_IEEE80211A:
117 		basic_rates = basic_rates_a;
118 		break;
119 	case HOSTAPD_MODE_IEEE80211B:
120 		basic_rates = basic_rates_b;
121 		break;
122 	case HOSTAPD_MODE_IEEE80211G:
123 		basic_rates = basic_rates_g;
124 		break;
125 	case HOSTAPD_MODE_IEEE80211AD:
126 		return 0; /* No basic rates for 11ad */
127 	default:
128 		return -1;
129 	}
130 
131 	i = 0;
132 	while (basic_rates[i] >= 0)
133 		i++;
134 	if (i)
135 		i++; /* -1 termination */
136 	os_free(iface->basic_rates);
137 	iface->basic_rates = os_malloc(i * sizeof(int));
138 	if (iface->basic_rates)
139 		os_memcpy(iface->basic_rates, basic_rates, i * sizeof(int));
140 
141 	os_free(iface->current_rates);
142 	iface->num_rates = 0;
143 
144 	iface->current_rates =
145 		os_calloc(mode->num_rates, sizeof(struct hostapd_rate_data));
146 	if (!iface->current_rates) {
147 		wpa_printf(MSG_ERROR, "Failed to allocate memory for rate "
148 			   "table.");
149 		return -1;
150 	}
151 
152 	for (i = 0; i < mode->num_rates; i++) {
153 		struct hostapd_rate_data *rate;
154 
155 		if (iface->conf->supported_rates &&
156 		    !hostapd_rate_found(iface->conf->supported_rates,
157 					mode->rates[i]))
158 			continue;
159 
160 		rate = &iface->current_rates[iface->num_rates];
161 		rate->rate = mode->rates[i];
162 		if (hostapd_rate_found(basic_rates, rate->rate)) {
163 			rate->flags |= HOSTAPD_RATE_BASIC;
164 			num_basic_rates++;
165 		}
166 		wpa_printf(MSG_DEBUG, "RATE[%d] rate=%d flags=0x%x",
167 			   iface->num_rates, rate->rate, rate->flags);
168 		iface->num_rates++;
169 	}
170 
171 	if ((iface->num_rates == 0 || num_basic_rates == 0) &&
172 	    (!iface->conf->ieee80211n || !iface->conf->require_ht)) {
173 		wpa_printf(MSG_ERROR, "No rates remaining in supported/basic "
174 			   "rate sets (%d,%d).",
175 			   iface->num_rates, num_basic_rates);
176 		return -1;
177 	}
178 
179 	return 0;
180 }
181 
182 
183 #ifdef CONFIG_IEEE80211N
184 static int ieee80211n_allowed_ht40_channel_pair(struct hostapd_iface *iface)
185 {
186 	int sec_chan, ok, j, first;
187 	int allowed[] = { 36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157,
188 			  184, 192 };
189 	size_t k;
190 
191 	if (!iface->conf->secondary_channel)
192 		return 1; /* HT40 not used */
193 
194 	sec_chan = iface->conf->channel + iface->conf->secondary_channel * 4;
195 	wpa_printf(MSG_DEBUG, "HT40: control channel: %d  "
196 		   "secondary channel: %d",
197 		   iface->conf->channel, sec_chan);
198 
199 	/* Verify that HT40 secondary channel is an allowed 20 MHz
200 	 * channel */
201 	ok = 0;
202 	for (j = 0; j < iface->current_mode->num_channels; j++) {
203 		struct hostapd_channel_data *chan =
204 			&iface->current_mode->channels[j];
205 		if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
206 		    chan->chan == sec_chan) {
207 			ok = 1;
208 			break;
209 		}
210 	}
211 	if (!ok) {
212 		wpa_printf(MSG_ERROR, "HT40 secondary channel %d not allowed",
213 			   sec_chan);
214 		return 0;
215 	}
216 
217 	/*
218 	 * Verify that HT40 primary,secondary channel pair is allowed per
219 	 * IEEE 802.11n Annex J. This is only needed for 5 GHz band since
220 	 * 2.4 GHz rules allow all cases where the secondary channel fits into
221 	 * the list of allowed channels (already checked above).
222 	 */
223 	if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A)
224 		return 1;
225 
226 	if (iface->conf->secondary_channel > 0)
227 		first = iface->conf->channel;
228 	else
229 		first = sec_chan;
230 
231 	ok = 0;
232 	for (k = 0; k < sizeof(allowed) / sizeof(allowed[0]); k++) {
233 		if (first == allowed[k]) {
234 			ok = 1;
235 			break;
236 		}
237 	}
238 	if (!ok) {
239 		wpa_printf(MSG_ERROR, "HT40 channel pair (%d, %d) not allowed",
240 			   iface->conf->channel,
241 			   iface->conf->secondary_channel);
242 		return 0;
243 	}
244 
245 	return 1;
246 }
247 
248 
249 static void ieee80211n_switch_pri_sec(struct hostapd_iface *iface)
250 {
251 	if (iface->conf->secondary_channel > 0) {
252 		iface->conf->channel += 4;
253 		iface->conf->secondary_channel = -1;
254 	} else {
255 		iface->conf->channel -= 4;
256 		iface->conf->secondary_channel = 1;
257 	}
258 }
259 
260 
261 static void ieee80211n_get_pri_sec_chan(struct wpa_scan_res *bss,
262 					int *pri_chan, int *sec_chan)
263 {
264 	struct ieee80211_ht_operation *oper;
265 	struct ieee802_11_elems elems;
266 
267 	*pri_chan = *sec_chan = 0;
268 
269 	ieee802_11_parse_elems((u8 *) (bss + 1), bss->ie_len, &elems, 0);
270 	if (elems.ht_operation &&
271 	    elems.ht_operation_len >= sizeof(*oper)) {
272 		oper = (struct ieee80211_ht_operation *) elems.ht_operation;
273 		*pri_chan = oper->control_chan;
274 		if (oper->ht_param & HT_INFO_HT_PARAM_REC_TRANS_CHNL_WIDTH) {
275 			int sec = oper->ht_param &
276 				HT_INFO_HT_PARAM_SECONDARY_CHNL_OFF_MASK;
277 			if (sec == HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE)
278 				*sec_chan = *pri_chan + 4;
279 			else if (sec == HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW)
280 				*sec_chan = *pri_chan - 4;
281 		}
282 	}
283 }
284 
285 
286 static int ieee80211n_check_40mhz_5g(struct hostapd_iface *iface,
287 				     struct wpa_scan_results *scan_res)
288 {
289 	int pri_chan, sec_chan, pri_freq, sec_freq, pri_bss, sec_bss;
290 	int bss_pri_chan, bss_sec_chan;
291 	size_t i;
292 	int match;
293 
294 	pri_chan = iface->conf->channel;
295 	sec_chan = iface->conf->secondary_channel * 4;
296 	pri_freq = hostapd_hw_get_freq(iface->bss[0], pri_chan);
297 	if (iface->conf->secondary_channel > 0)
298 		sec_freq = pri_freq + 20;
299 	else
300 		sec_freq = pri_freq - 20;
301 
302 	/*
303 	 * Switch PRI/SEC channels if Beacons were detected on selected SEC
304 	 * channel, but not on selected PRI channel.
305 	 */
306 	pri_bss = sec_bss = 0;
307 	for (i = 0; i < scan_res->num; i++) {
308 		struct wpa_scan_res *bss = scan_res->res[i];
309 		if (bss->freq == pri_freq)
310 			pri_bss++;
311 		else if (bss->freq == sec_freq)
312 			sec_bss++;
313 	}
314 	if (sec_bss && !pri_bss) {
315 		wpa_printf(MSG_INFO, "Switch own primary and secondary "
316 			   "channel to get secondary channel with no Beacons "
317 			   "from other BSSes");
318 		ieee80211n_switch_pri_sec(iface);
319 	}
320 
321 	/*
322 	 * Match PRI/SEC channel with any existing HT40 BSS on the same
323 	 * channels that we are about to use (if already mixed order in
324 	 * existing BSSes, use own preference).
325 	 */
326 	match = 0;
327 	for (i = 0; i < scan_res->num; i++) {
328 		struct wpa_scan_res *bss = scan_res->res[i];
329 		ieee80211n_get_pri_sec_chan(bss, &bss_pri_chan, &bss_sec_chan);
330 		if (pri_chan == bss_pri_chan &&
331 		    sec_chan == bss_sec_chan) {
332 			match = 1;
333 			break;
334 		}
335 	}
336 	if (!match) {
337 		for (i = 0; i < scan_res->num; i++) {
338 			struct wpa_scan_res *bss = scan_res->res[i];
339 			ieee80211n_get_pri_sec_chan(bss, &bss_pri_chan,
340 						    &bss_sec_chan);
341 			if (pri_chan == bss_sec_chan &&
342 			    sec_chan == bss_pri_chan) {
343 				wpa_printf(MSG_INFO, "Switch own primary and "
344 					   "secondary channel due to BSS "
345 					   "overlap with " MACSTR,
346 					   MAC2STR(bss->bssid));
347 				ieee80211n_switch_pri_sec(iface);
348 				break;
349 			}
350 		}
351 	}
352 
353 	return 1;
354 }
355 
356 
357 static int ieee80211n_check_40mhz_2g4(struct hostapd_iface *iface,
358 				      struct wpa_scan_results *scan_res)
359 {
360 	int pri_freq, sec_freq;
361 	int affected_start, affected_end;
362 	size_t i;
363 
364 	pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);
365 	if (iface->conf->secondary_channel > 0)
366 		sec_freq = pri_freq + 20;
367 	else
368 		sec_freq = pri_freq - 20;
369 	affected_start = (pri_freq + sec_freq) / 2 - 25;
370 	affected_end = (pri_freq + sec_freq) / 2 + 25;
371 	wpa_printf(MSG_DEBUG, "40 MHz affected channel range: [%d,%d] MHz",
372 		   affected_start, affected_end);
373 	for (i = 0; i < scan_res->num; i++) {
374 		struct wpa_scan_res *bss = scan_res->res[i];
375 		int pri = bss->freq;
376 		int sec = pri;
377 		int sec_chan, pri_chan;
378 
379 		ieee80211n_get_pri_sec_chan(bss, &pri_chan, &sec_chan);
380 
381 		if (sec_chan) {
382 			if (sec_chan < pri_chan)
383 				sec = pri - 20;
384 			else
385 				sec = pri + 20;
386 		}
387 
388 		if ((pri < affected_start || pri > affected_end) &&
389 		    (sec < affected_start || sec > affected_end))
390 			continue; /* not within affected channel range */
391 
392 		wpa_printf(MSG_DEBUG, "Neighboring BSS: " MACSTR
393 			   " freq=%d pri=%d sec=%d",
394 			   MAC2STR(bss->bssid), bss->freq, pri_chan, sec_chan);
395 
396 		if (sec_chan) {
397 			if (pri_freq != pri || sec_freq != sec) {
398 				wpa_printf(MSG_DEBUG, "40 MHz pri/sec "
399 					   "mismatch with BSS " MACSTR
400 					   " <%d,%d> (chan=%d%c) vs. <%d,%d>",
401 					   MAC2STR(bss->bssid),
402 					   pri, sec, pri_chan,
403 					   sec > pri ? '+' : '-',
404 					   pri_freq, sec_freq);
405 				return 0;
406 			}
407 		}
408 
409 		/* TODO: 40 MHz intolerant */
410 	}
411 
412 	return 1;
413 }
414 
415 
416 static void ieee80211n_check_scan(struct hostapd_iface *iface)
417 {
418 	struct wpa_scan_results *scan_res;
419 	int oper40;
420 	int res;
421 
422 	/* Check list of neighboring BSSes (from scan) to see whether 40 MHz is
423 	 * allowed per IEEE Std 802.11-2012, 10.15.3.2 */
424 
425 	iface->scan_cb = NULL;
426 
427 	scan_res = hostapd_driver_get_scan_results(iface->bss[0]);
428 	if (scan_res == NULL) {
429 		hostapd_setup_interface_complete(iface, 1);
430 		return;
431 	}
432 
433 	if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211A)
434 		oper40 = ieee80211n_check_40mhz_5g(iface, scan_res);
435 	else
436 		oper40 = ieee80211n_check_40mhz_2g4(iface, scan_res);
437 	wpa_scan_results_free(scan_res);
438 
439 	if (!oper40) {
440 		wpa_printf(MSG_INFO, "20/40 MHz operation not permitted on "
441 			   "channel pri=%d sec=%d based on overlapping BSSes",
442 			   iface->conf->channel,
443 			   iface->conf->channel +
444 			   iface->conf->secondary_channel * 4);
445 		iface->conf->secondary_channel = 0;
446 		iface->conf->ht_capab &= ~HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET;
447 	}
448 
449 	res = ieee80211n_allowed_ht40_channel_pair(iface);
450 	hostapd_setup_interface_complete(iface, !res);
451 }
452 
453 
454 static void ieee80211n_scan_channels_2g4(struct hostapd_iface *iface,
455 					 struct wpa_driver_scan_params *params)
456 {
457 	/* Scan only the affected frequency range */
458 	int pri_freq, sec_freq;
459 	int affected_start, affected_end;
460 	int i, pos;
461 	struct hostapd_hw_modes *mode;
462 
463 	if (iface->current_mode == NULL)
464 		return;
465 
466 	pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);
467 	if (iface->conf->secondary_channel > 0)
468 		sec_freq = pri_freq + 20;
469 	else
470 		sec_freq = pri_freq - 20;
471 	affected_start = (pri_freq + sec_freq) / 2 - 25;
472 	affected_end = (pri_freq + sec_freq) / 2 + 25;
473 	wpa_printf(MSG_DEBUG, "40 MHz affected channel range: [%d,%d] MHz",
474 		   affected_start, affected_end);
475 
476 	mode = iface->current_mode;
477 	params->freqs = os_calloc(mode->num_channels + 1, sizeof(int));
478 	if (params->freqs == NULL)
479 		return;
480 	pos = 0;
481 
482 	for (i = 0; i < mode->num_channels; i++) {
483 		struct hostapd_channel_data *chan = &mode->channels[i];
484 		if (chan->flag & HOSTAPD_CHAN_DISABLED)
485 			continue;
486 		if (chan->freq < affected_start ||
487 		    chan->freq > affected_end)
488 			continue;
489 		params->freqs[pos++] = chan->freq;
490 	}
491 }
492 
493 
494 static int ieee80211n_check_40mhz(struct hostapd_iface *iface)
495 {
496 	struct wpa_driver_scan_params params;
497 
498 	if (!iface->conf->secondary_channel)
499 		return 0; /* HT40 not used */
500 
501 	wpa_printf(MSG_DEBUG, "Scan for neighboring BSSes prior to enabling "
502 		   "40 MHz channel");
503 	os_memset(&params, 0, sizeof(params));
504 	if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211G)
505 		ieee80211n_scan_channels_2g4(iface, &params);
506 	if (hostapd_driver_scan(iface->bss[0], &params) < 0) {
507 		wpa_printf(MSG_ERROR, "Failed to request a scan of "
508 			   "neighboring BSSes");
509 		os_free(params.freqs);
510 		return -1;
511 	}
512 	os_free(params.freqs);
513 
514 	iface->scan_cb = ieee80211n_check_scan;
515 	return 1;
516 }
517 
518 
519 static int ieee80211n_supported_ht_capab(struct hostapd_iface *iface)
520 {
521 	u16 hw = iface->current_mode->ht_capab;
522 	u16 conf = iface->conf->ht_capab;
523 
524 	if ((conf & HT_CAP_INFO_LDPC_CODING_CAP) &&
525 	    !(hw & HT_CAP_INFO_LDPC_CODING_CAP)) {
526 		wpa_printf(MSG_ERROR, "Driver does not support configured "
527 			   "HT capability [LDPC]");
528 		return 0;
529 	}
530 
531 	if ((conf & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&
532 	    !(hw & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) {
533 		wpa_printf(MSG_ERROR, "Driver does not support configured "
534 			   "HT capability [HT40*]");
535 		return 0;
536 	}
537 
538 	if ((conf & HT_CAP_INFO_SMPS_MASK) != (hw & HT_CAP_INFO_SMPS_MASK) &&
539 	    (conf & HT_CAP_INFO_SMPS_MASK) != HT_CAP_INFO_SMPS_DISABLED) {
540 		wpa_printf(MSG_ERROR, "Driver does not support configured "
541 			   "HT capability [SMPS-*]");
542 		return 0;
543 	}
544 
545 	if ((conf & HT_CAP_INFO_GREEN_FIELD) &&
546 	    !(hw & HT_CAP_INFO_GREEN_FIELD)) {
547 		wpa_printf(MSG_ERROR, "Driver does not support configured "
548 			   "HT capability [GF]");
549 		return 0;
550 	}
551 
552 	if ((conf & HT_CAP_INFO_SHORT_GI20MHZ) &&
553 	    !(hw & HT_CAP_INFO_SHORT_GI20MHZ)) {
554 		wpa_printf(MSG_ERROR, "Driver does not support configured "
555 			   "HT capability [SHORT-GI-20]");
556 		return 0;
557 	}
558 
559 	if ((conf & HT_CAP_INFO_SHORT_GI40MHZ) &&
560 	    !(hw & HT_CAP_INFO_SHORT_GI40MHZ)) {
561 		wpa_printf(MSG_ERROR, "Driver does not support configured "
562 			   "HT capability [SHORT-GI-40]");
563 		return 0;
564 	}
565 
566 	if ((conf & HT_CAP_INFO_TX_STBC) && !(hw & HT_CAP_INFO_TX_STBC)) {
567 		wpa_printf(MSG_ERROR, "Driver does not support configured "
568 			   "HT capability [TX-STBC]");
569 		return 0;
570 	}
571 
572 	if ((conf & HT_CAP_INFO_RX_STBC_MASK) >
573 	    (hw & HT_CAP_INFO_RX_STBC_MASK)) {
574 		wpa_printf(MSG_ERROR, "Driver does not support configured "
575 			   "HT capability [RX-STBC*]");
576 		return 0;
577 	}
578 
579 	if ((conf & HT_CAP_INFO_DELAYED_BA) &&
580 	    !(hw & HT_CAP_INFO_DELAYED_BA)) {
581 		wpa_printf(MSG_ERROR, "Driver does not support configured "
582 			   "HT capability [DELAYED-BA]");
583 		return 0;
584 	}
585 
586 	if ((conf & HT_CAP_INFO_MAX_AMSDU_SIZE) &&
587 	    !(hw & HT_CAP_INFO_MAX_AMSDU_SIZE)) {
588 		wpa_printf(MSG_ERROR, "Driver does not support configured "
589 			   "HT capability [MAX-AMSDU-7935]");
590 		return 0;
591 	}
592 
593 	if ((conf & HT_CAP_INFO_DSSS_CCK40MHZ) &&
594 	    !(hw & HT_CAP_INFO_DSSS_CCK40MHZ)) {
595 		wpa_printf(MSG_ERROR, "Driver does not support configured "
596 			   "HT capability [DSSS_CCK-40]");
597 		return 0;
598 	}
599 
600 	if ((conf & HT_CAP_INFO_PSMP_SUPP) && !(hw & HT_CAP_INFO_PSMP_SUPP)) {
601 		wpa_printf(MSG_ERROR, "Driver does not support configured "
602 			   "HT capability [PSMP]");
603 		return 0;
604 	}
605 
606 	if ((conf & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT) &&
607 	    !(hw & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT)) {
608 		wpa_printf(MSG_ERROR, "Driver does not support configured "
609 			   "HT capability [LSIG-TXOP-PROT]");
610 		return 0;
611 	}
612 
613 	return 1;
614 }
615 
616 #endif /* CONFIG_IEEE80211N */
617 
618 
619 int hostapd_check_ht_capab(struct hostapd_iface *iface)
620 {
621 #ifdef CONFIG_IEEE80211N
622 	int ret;
623 	if (!iface->conf->ieee80211n)
624 		return 0;
625 	if (!ieee80211n_supported_ht_capab(iface))
626 		return -1;
627 	ret = ieee80211n_check_40mhz(iface);
628 	if (ret)
629 		return ret;
630 	if (!ieee80211n_allowed_ht40_channel_pair(iface))
631 		return -1;
632 #endif /* CONFIG_IEEE80211N */
633 
634 	return 0;
635 }
636 
637 
638 /**
639  * hostapd_select_hw_mode - Select the hardware mode
640  * @iface: Pointer to interface data.
641  * Returns: 0 on success, < 0 on failure
642  *
643  * Sets up the hardware mode, channel, rates, and passive scanning
644  * based on the configuration.
645  */
646 int hostapd_select_hw_mode(struct hostapd_iface *iface)
647 {
648 	int i, j, ok;
649 
650 	if (iface->num_hw_features < 1)
651 		return -1;
652 
653 	iface->current_mode = NULL;
654 	for (i = 0; i < iface->num_hw_features; i++) {
655 		struct hostapd_hw_modes *mode = &iface->hw_features[i];
656 		if (mode->mode == iface->conf->hw_mode) {
657 			iface->current_mode = mode;
658 			break;
659 		}
660 	}
661 
662 	if (iface->current_mode == NULL) {
663 		wpa_printf(MSG_ERROR, "Hardware does not support configured "
664 			   "mode");
665 		hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
666 			       HOSTAPD_LEVEL_WARNING,
667 			       "Hardware does not support configured mode "
668 			       "(%d) (hw_mode in hostapd.conf)",
669 			       (int) iface->conf->hw_mode);
670 		return -2;
671 	}
672 
673 	ok = 0;
674 	for (j = 0; j < iface->current_mode->num_channels; j++) {
675 		struct hostapd_channel_data *chan =
676 			&iface->current_mode->channels[j];
677 		if (chan->chan == iface->conf->channel) {
678 			if (chan->flag & HOSTAPD_CHAN_DISABLED) {
679 				wpa_printf(MSG_ERROR,
680 					   "channel [%i] (%i) is disabled for "
681 					   "use in AP mode, flags: 0x%x%s%s%s",
682 					   j, chan->chan, chan->flag,
683 					   chan->flag & HOSTAPD_CHAN_NO_IBSS ?
684 					   " NO-IBSS" : "",
685 					   chan->flag &
686 					   HOSTAPD_CHAN_PASSIVE_SCAN ?
687 					   " PASSIVE-SCAN" : "",
688 					   chan->flag & HOSTAPD_CHAN_RADAR ?
689 					   " RADAR" : "");
690 			} else {
691 				ok = 1;
692 				break;
693 			}
694 		}
695 	}
696 	if (ok && iface->conf->secondary_channel) {
697 		int sec_ok = 0;
698 		int sec_chan = iface->conf->channel +
699 			iface->conf->secondary_channel * 4;
700 		for (j = 0; j < iface->current_mode->num_channels; j++) {
701 			struct hostapd_channel_data *chan =
702 				&iface->current_mode->channels[j];
703 			if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
704 			    (chan->chan == sec_chan)) {
705 				sec_ok = 1;
706 				break;
707 			}
708 		}
709 		if (!sec_ok) {
710 			hostapd_logger(iface->bss[0], NULL,
711 				       HOSTAPD_MODULE_IEEE80211,
712 				       HOSTAPD_LEVEL_WARNING,
713 				       "Configured HT40 secondary channel "
714 				       "(%d) not found from the channel list "
715 				       "of current mode (%d) %s",
716 				       sec_chan, iface->current_mode->mode,
717 				       hostapd_hw_mode_txt(
718 					       iface->current_mode->mode));
719 			ok = 0;
720 		}
721 	}
722 	if (iface->conf->channel == 0) {
723 		/* TODO: could request a scan of neighboring BSSes and select
724 		 * the channel automatically */
725 		wpa_printf(MSG_ERROR, "Channel not configured "
726 			   "(hw_mode/channel in hostapd.conf)");
727 		return -3;
728 	}
729 	if (ok == 0 && iface->conf->channel != 0) {
730 		hostapd_logger(iface->bss[0], NULL,
731 			       HOSTAPD_MODULE_IEEE80211,
732 			       HOSTAPD_LEVEL_WARNING,
733 			       "Configured channel (%d) not found from the "
734 			       "channel list of current mode (%d) %s",
735 			       iface->conf->channel,
736 			       iface->current_mode->mode,
737 			       hostapd_hw_mode_txt(iface->current_mode->mode));
738 		iface->current_mode = NULL;
739 	}
740 
741 	if (iface->current_mode == NULL) {
742 		hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
743 			       HOSTAPD_LEVEL_WARNING,
744 			       "Hardware does not support configured channel");
745 		return -4;
746 	}
747 
748 	return 0;
749 }
750 
751 
752 const char * hostapd_hw_mode_txt(int mode)
753 {
754 	switch (mode) {
755 	case HOSTAPD_MODE_IEEE80211A:
756 		return "IEEE 802.11a";
757 	case HOSTAPD_MODE_IEEE80211B:
758 		return "IEEE 802.11b";
759 	case HOSTAPD_MODE_IEEE80211G:
760 		return "IEEE 802.11g";
761 	case HOSTAPD_MODE_IEEE80211AD:
762 		return "IEEE 802.11ad";
763 	default:
764 		return "UNKNOWN";
765 	}
766 }
767 
768 
769 int hostapd_hw_get_freq(struct hostapd_data *hapd, int chan)
770 {
771 	int i;
772 
773 	if (!hapd->iface->current_mode)
774 		return 0;
775 
776 	for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
777 		struct hostapd_channel_data *ch =
778 			&hapd->iface->current_mode->channels[i];
779 		if (ch->chan == chan)
780 			return ch->freq;
781 	}
782 
783 	return 0;
784 }
785 
786 
787 int hostapd_hw_get_channel(struct hostapd_data *hapd, int freq)
788 {
789 	int i;
790 
791 	if (!hapd->iface->current_mode)
792 		return 0;
793 
794 	for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
795 		struct hostapd_channel_data *ch =
796 			&hapd->iface->current_mode->channels[i];
797 		if (ch->freq == freq)
798 			return ch->chan;
799 	}
800 
801 	return 0;
802 }
803