dfs.c revision 96be6222df414a7dde5c5b1b72df22e67b1a77fc
1/*
2 * DFS - Dynamic Frequency Selection
3 * Copyright (c) 2002-2013, Jouni Malinen <j@w1.fi>
4 * Copyright (c) 2013, Qualcomm Atheros, Inc.
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 "common/ieee802_11_defs.h"
14#include "common/wpa_ctrl.h"
15#include "hostapd.h"
16#include "ap_drv_ops.h"
17#include "drivers/driver.h"
18#include "dfs.h"
19
20
21static int dfs_get_used_n_chans(struct hostapd_iface *iface)
22{
23	int n_chans = 1;
24
25	if (iface->conf->ieee80211n && iface->conf->secondary_channel)
26		n_chans = 2;
27
28	if (iface->conf->ieee80211ac) {
29		switch (iface->conf->vht_oper_chwidth) {
30		case VHT_CHANWIDTH_USE_HT:
31			break;
32		case VHT_CHANWIDTH_80MHZ:
33			n_chans = 4;
34			break;
35		case VHT_CHANWIDTH_160MHZ:
36			n_chans = 8;
37			break;
38		default:
39			break;
40		}
41	}
42
43	return n_chans;
44}
45
46
47static int dfs_channel_available(struct hostapd_channel_data *chan,
48				 int skip_radar)
49{
50	/*
51	 * When radar detection happens, CSA is performed. However, there's no
52	 * time for CAC, so radar channels must be skipped when finding a new
53	 * channel for CSA.
54	 */
55	if (skip_radar && chan->flag & HOSTAPD_CHAN_RADAR)
56		return 0;
57
58	if (chan->flag & HOSTAPD_CHAN_DISABLED)
59		return 0;
60	if ((chan->flag & HOSTAPD_CHAN_RADAR) &&
61	    ((chan->flag & HOSTAPD_CHAN_DFS_MASK) ==
62	     HOSTAPD_CHAN_DFS_UNAVAILABLE))
63		return 0;
64	return 1;
65}
66
67
68static int dfs_is_chan_allowed(struct hostapd_channel_data *chan, int n_chans)
69{
70	/*
71	 * The tables contain first valid channel number based on channel width.
72	 * We will also choose this first channel as the control one.
73	 */
74	int allowed_40[] = { 36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157,
75			     184, 192 };
76	/*
77	 * VHT80, valid channels based on center frequency:
78	 * 42, 58, 106, 122, 138, 155
79	 */
80	int allowed_80[] = { 36, 52, 100, 116, 132, 149 };
81	int *allowed = allowed_40;
82	unsigned int i, allowed_no = 0;
83
84	switch (n_chans) {
85	case 2:
86		allowed = allowed_40;
87		allowed_no = ARRAY_SIZE(allowed_40);
88		break;
89	case 4:
90		allowed = allowed_80;
91		allowed_no = ARRAY_SIZE(allowed_80);
92		break;
93	default:
94		wpa_printf(MSG_DEBUG, "Unknown width for %d channels", n_chans);
95		break;
96	}
97
98	for (i = 0; i < allowed_no; i++) {
99		if (chan->chan == allowed[i])
100			return 1;
101	}
102
103	return 0;
104}
105
106
107static int dfs_chan_range_available(struct hostapd_hw_modes *mode,
108				    int first_chan_idx, int num_chans,
109				    int skip_radar)
110{
111	struct hostapd_channel_data *first_chan, *chan;
112	int i;
113
114	if (first_chan_idx + num_chans >= mode->num_channels)
115		return 0;
116
117	first_chan = &mode->channels[first_chan_idx];
118
119	for (i = 0; i < num_chans; i++) {
120		chan = &mode->channels[first_chan_idx + i];
121
122		if (first_chan->freq + i * 20 != chan->freq)
123			return 0;
124
125		if (!dfs_channel_available(chan, skip_radar))
126			return 0;
127	}
128
129	return 1;
130}
131
132
133/*
134 * The function assumes HT40+ operation.
135 * Make sure to adjust the following variables after calling this:
136 *  - hapd->secondary_channel
137 *  - hapd->vht_oper_centr_freq_seg0_idx
138 *  - hapd->vht_oper_centr_freq_seg1_idx
139 */
140static int dfs_find_channel(struct hostapd_iface *iface,
141			    struct hostapd_channel_data **ret_chan,
142			    int idx, int skip_radar)
143{
144	struct hostapd_hw_modes *mode;
145	struct hostapd_channel_data *chan;
146	int i, channel_idx = 0, n_chans;
147
148	mode = iface->current_mode;
149	n_chans = dfs_get_used_n_chans(iface);
150
151	wpa_printf(MSG_DEBUG, "DFS new chan checking %d channels", n_chans);
152	for (i = 0; i < mode->num_channels; i++) {
153		chan = &mode->channels[i];
154
155		/* Skip HT40/VHT incompatible channels */
156		if (iface->conf->ieee80211n &&
157		    iface->conf->secondary_channel &&
158		    !dfs_is_chan_allowed(chan, n_chans))
159			continue;
160
161		/* Skip incompatible chandefs */
162		if (!dfs_chan_range_available(mode, i, n_chans, skip_radar))
163			continue;
164
165		if (ret_chan && idx == channel_idx) {
166			wpa_printf(MSG_DEBUG, "Selected ch. #%d", chan->chan);
167			*ret_chan = chan;
168			return idx;
169		}
170		wpa_printf(MSG_DEBUG, "Adding channel: %d", chan->chan);
171		channel_idx++;
172	}
173	return channel_idx;
174}
175
176
177static void dfs_adjust_vht_center_freq(struct hostapd_iface *iface,
178				       struct hostapd_channel_data *chan,
179				       int secondary_channel,
180				       u8 *vht_oper_centr_freq_seg0_idx,
181				       u8 *vht_oper_centr_freq_seg1_idx)
182{
183	if (!iface->conf->ieee80211ac)
184		return;
185
186	if (!chan)
187		return;
188
189	*vht_oper_centr_freq_seg1_idx = 0;
190
191	switch (iface->conf->vht_oper_chwidth) {
192	case VHT_CHANWIDTH_USE_HT:
193		if (secondary_channel == 1)
194			*vht_oper_centr_freq_seg0_idx = chan->chan + 2;
195		else if (secondary_channel == -1)
196			*vht_oper_centr_freq_seg0_idx = chan->chan - 2;
197		else
198			*vht_oper_centr_freq_seg0_idx = chan->chan;
199		break;
200	case VHT_CHANWIDTH_80MHZ:
201		*vht_oper_centr_freq_seg0_idx = chan->chan + 6;
202		break;
203	case VHT_CHANWIDTH_160MHZ:
204		*vht_oper_centr_freq_seg0_idx = chan->chan + 14;
205		break;
206	default:
207		wpa_printf(MSG_INFO, "DFS only VHT20/40/80/160 is supported now");
208		break;
209	}
210
211	wpa_printf(MSG_DEBUG, "DFS adjusting VHT center frequency: %d, %d",
212		   *vht_oper_centr_freq_seg0_idx,
213		   *vht_oper_centr_freq_seg1_idx);
214}
215
216
217/* Return start channel idx we will use for mode->channels[idx] */
218static int dfs_get_start_chan_idx(struct hostapd_iface *iface)
219{
220	struct hostapd_hw_modes *mode;
221	struct hostapd_channel_data *chan;
222	int channel_no = iface->conf->channel;
223	int res = -1, i;
224
225	/* HT40- */
226	if (iface->conf->ieee80211n && iface->conf->secondary_channel == -1)
227		channel_no -= 4;
228
229	/* VHT */
230	if (iface->conf->ieee80211ac) {
231		switch (iface->conf->vht_oper_chwidth) {
232		case VHT_CHANWIDTH_USE_HT:
233			break;
234		case VHT_CHANWIDTH_80MHZ:
235			channel_no =
236				iface->conf->vht_oper_centr_freq_seg0_idx - 6;
237			break;
238		case VHT_CHANWIDTH_160MHZ:
239			channel_no =
240				iface->conf->vht_oper_centr_freq_seg0_idx - 14;
241			break;
242		default:
243			wpa_printf(MSG_INFO,
244				   "DFS only VHT20/40/80/160 is supported now");
245			channel_no = -1;
246			break;
247		}
248	}
249
250	/* Get idx */
251	mode = iface->current_mode;
252	for (i = 0; i < mode->num_channels; i++) {
253		chan = &mode->channels[i];
254		if (chan->chan == channel_no) {
255			res = i;
256			break;
257		}
258	}
259
260	if (res == -1)
261		wpa_printf(MSG_DEBUG, "DFS chan_idx seems wrong: -1");
262
263	return res;
264}
265
266
267/* At least one channel have radar flag */
268static int dfs_check_chans_radar(struct hostapd_iface *iface,
269				 int start_chan_idx, int n_chans)
270{
271	struct hostapd_channel_data *channel;
272	struct hostapd_hw_modes *mode;
273	int i, res = 0;
274
275	mode = iface->current_mode;
276
277	for (i = 0; i < n_chans; i++) {
278		channel = &mode->channels[start_chan_idx + i];
279		if (channel->flag & HOSTAPD_CHAN_RADAR)
280			res++;
281	}
282
283	return res;
284}
285
286
287/* All channels available */
288static int dfs_check_chans_available(struct hostapd_iface *iface,
289				     int start_chan_idx, int n_chans)
290{
291	struct hostapd_channel_data *channel;
292	struct hostapd_hw_modes *mode;
293	int i;
294
295	mode = iface->current_mode;
296
297	for(i = 0; i < n_chans; i++) {
298		channel = &mode->channels[start_chan_idx + i];
299		if ((channel->flag & HOSTAPD_CHAN_DFS_MASK) !=
300		    HOSTAPD_CHAN_DFS_AVAILABLE)
301			break;
302	}
303
304	return i == n_chans;
305}
306
307
308/* At least one channel unavailable */
309static int dfs_check_chans_unavailable(struct hostapd_iface *iface,
310				       int start_chan_idx,
311				       int n_chans)
312{
313	struct hostapd_channel_data *channel;
314	struct hostapd_hw_modes *mode;
315	int i, res = 0;
316
317	mode = iface->current_mode;
318
319	for(i = 0; i < n_chans; i++) {
320		channel = &mode->channels[start_chan_idx + i];
321		if (channel->flag & HOSTAPD_CHAN_DISABLED)
322			res++;
323		if ((channel->flag & HOSTAPD_CHAN_DFS_MASK) ==
324		    HOSTAPD_CHAN_DFS_UNAVAILABLE)
325			res++;
326	}
327
328	return res;
329}
330
331
332static struct hostapd_channel_data *
333dfs_get_valid_channel(struct hostapd_iface *iface,
334		      int *secondary_channel,
335		      u8 *vht_oper_centr_freq_seg0_idx,
336		      u8 *vht_oper_centr_freq_seg1_idx,
337		      int skip_radar)
338{
339	struct hostapd_hw_modes *mode;
340	struct hostapd_channel_data *chan = NULL;
341	int num_available_chandefs;
342	int chan_idx;
343	u32 _rand;
344
345	wpa_printf(MSG_DEBUG, "DFS: Selecting random channel");
346
347	if (iface->current_mode == NULL)
348		return NULL;
349
350	mode = iface->current_mode;
351	if (mode->mode != HOSTAPD_MODE_IEEE80211A)
352		return NULL;
353
354	/* Get the count first */
355	num_available_chandefs = dfs_find_channel(iface, NULL, 0, skip_radar);
356	if (num_available_chandefs == 0)
357		return NULL;
358
359	os_get_random((u8 *) &_rand, sizeof(_rand));
360	chan_idx = _rand % num_available_chandefs;
361	dfs_find_channel(iface, &chan, chan_idx, skip_radar);
362
363	/* dfs_find_channel() calculations assume HT40+ */
364	if (iface->conf->secondary_channel)
365		*secondary_channel = 1;
366	else
367		*secondary_channel = 0;
368
369	dfs_adjust_vht_center_freq(iface, chan,
370				   *secondary_channel,
371				   vht_oper_centr_freq_seg0_idx,
372				   vht_oper_centr_freq_seg1_idx);
373
374	return chan;
375}
376
377
378static int set_dfs_state_freq(struct hostapd_iface *iface, int freq, u32 state)
379{
380	struct hostapd_hw_modes *mode;
381	struct hostapd_channel_data *chan = NULL;
382	int i;
383
384	mode = iface->current_mode;
385	if (mode == NULL)
386		return 0;
387
388	wpa_printf(MSG_DEBUG, "set_dfs_state 0x%X for %d MHz", state, freq);
389	for (i = 0; i < iface->current_mode->num_channels; i++) {
390		chan = &iface->current_mode->channels[i];
391		if (chan->freq == freq) {
392			if (chan->flag & HOSTAPD_CHAN_RADAR) {
393				chan->flag &= ~HOSTAPD_CHAN_DFS_MASK;
394				chan->flag |= state;
395				return 1; /* Channel found */
396			}
397		}
398	}
399	wpa_printf(MSG_WARNING, "Can't set DFS state for freq %d MHz", freq);
400	return 0;
401}
402
403
404static int set_dfs_state(struct hostapd_iface *iface, int freq, int ht_enabled,
405			 int chan_offset, int chan_width, int cf1,
406			 int cf2, u32 state)
407{
408	int n_chans = 1, i;
409	struct hostapd_hw_modes *mode;
410	int frequency = freq;
411	int ret = 0;
412
413	mode = iface->current_mode;
414	if (mode == NULL)
415		return 0;
416
417	if (mode->mode != HOSTAPD_MODE_IEEE80211A) {
418		wpa_printf(MSG_WARNING, "current_mode != IEEE80211A");
419		return 0;
420	}
421
422	/* Seems cf1 and chan_width is enough here */
423	switch (chan_width) {
424	case CHAN_WIDTH_20_NOHT:
425	case CHAN_WIDTH_20:
426		n_chans = 1;
427		if (frequency == 0)
428			frequency = cf1;
429		break;
430	case CHAN_WIDTH_40:
431		n_chans = 2;
432		frequency = cf1 - 10;
433		break;
434	case CHAN_WIDTH_80:
435		n_chans = 4;
436		frequency = cf1 - 30;
437		break;
438	case CHAN_WIDTH_160:
439		n_chans = 8;
440		frequency = cf1 - 70;
441		break;
442	default:
443		wpa_printf(MSG_INFO, "DFS chan_width %d not supported",
444			   chan_width);
445		break;
446	}
447
448	wpa_printf(MSG_DEBUG, "DFS freq: %dMHz, n_chans: %d", frequency,
449		   n_chans);
450	for (i = 0; i < n_chans; i++) {
451		ret += set_dfs_state_freq(iface, frequency, state);
452		frequency = frequency + 20;
453	}
454
455	return ret;
456}
457
458
459static int dfs_are_channels_overlapped(struct hostapd_iface *iface, int freq,
460				       int chan_width, int cf1, int cf2)
461{
462	int start_chan_idx;
463	struct hostapd_hw_modes *mode;
464	struct hostapd_channel_data *chan;
465	int n_chans, i, j, frequency = freq, radar_n_chans = 1;
466	u8 radar_chan;
467	int res = 0;
468
469	/* Our configuration */
470	mode = iface->current_mode;
471	start_chan_idx = dfs_get_start_chan_idx(iface);
472	n_chans = dfs_get_used_n_chans(iface);
473
474	/* Check we are on DFS channel(s) */
475	if (!dfs_check_chans_radar(iface, start_chan_idx, n_chans))
476		return 0;
477
478	/* Reported via radar event */
479	switch (chan_width) {
480	case CHAN_WIDTH_20_NOHT:
481	case CHAN_WIDTH_20:
482		radar_n_chans = 1;
483		if (frequency == 0)
484			frequency = cf1;
485		break;
486	case CHAN_WIDTH_40:
487		radar_n_chans = 2;
488		frequency = cf1 - 10;
489		break;
490	case CHAN_WIDTH_80:
491		radar_n_chans = 4;
492		frequency = cf1 - 30;
493		break;
494	case CHAN_WIDTH_160:
495		radar_n_chans = 8;
496		frequency = cf1 - 70;
497		break;
498	default:
499		wpa_printf(MSG_INFO, "DFS chan_width %d not supported",
500			   chan_width);
501		break;
502	}
503
504	ieee80211_freq_to_chan(frequency, &radar_chan);
505
506	for (i = 0; i < n_chans; i++) {
507		chan = &mode->channels[start_chan_idx + i];
508		if (!(chan->flag & HOSTAPD_CHAN_RADAR))
509			continue;
510		for (j = 0; j < radar_n_chans; j++) {
511			wpa_printf(MSG_DEBUG, "checking our: %d, radar: %d",
512				   chan->chan, radar_chan + j * 4);
513			if (chan->chan == radar_chan + j * 4)
514				res++;
515		}
516	}
517
518	wpa_printf(MSG_DEBUG, "overlapped: %d", res);
519
520	return res;
521}
522
523
524/*
525 * Main DFS handler
526 * 1 - continue channel/ap setup
527 * 0 - channel/ap setup will be continued after CAC
528 * -1 - hit critical error
529 */
530int hostapd_handle_dfs(struct hostapd_iface *iface)
531{
532	struct hostapd_channel_data *channel;
533	int res, n_chans, start_chan_idx;
534	int skip_radar = 0;
535
536	iface->cac_started = 0;
537
538	do {
539		/* Get start (first) channel for current configuration */
540		start_chan_idx = dfs_get_start_chan_idx(iface);
541		if (start_chan_idx == -1)
542			return -1;
543
544		/* Get number of used channels, depend on width */
545		n_chans = dfs_get_used_n_chans(iface);
546
547		/* Check if any of configured channels require DFS */
548		res = dfs_check_chans_radar(iface, start_chan_idx, n_chans);
549		wpa_printf(MSG_DEBUG,
550			   "DFS %d channels required radar detection",
551			   res);
552		if (!res)
553			return 1;
554
555		/* Check if all channels are DFS available */
556		res = dfs_check_chans_available(iface, start_chan_idx, n_chans);
557		wpa_printf(MSG_DEBUG,
558			   "DFS all channels available, (SKIP CAC): %s",
559			   res ? "yes" : "no");
560		if (res)
561			return 1;
562
563		/* Check if any of configured channels is unavailable */
564		res = dfs_check_chans_unavailable(iface, start_chan_idx,
565						  n_chans);
566		wpa_printf(MSG_DEBUG, "DFS %d chans unavailable - choose other channel: %s",
567			   res, res ? "yes": "no");
568		if (res) {
569			int sec = 0;
570			u8 cf1 = 0, cf2 = 0;
571
572			channel = dfs_get_valid_channel(iface, &sec, &cf1, &cf2,
573							skip_radar);
574			if (!channel) {
575				wpa_printf(MSG_ERROR, "could not get valid channel");
576				return -1;
577			}
578
579			iface->freq = channel->freq;
580			iface->conf->channel = channel->chan;
581			iface->conf->secondary_channel = sec;
582			iface->conf->vht_oper_centr_freq_seg0_idx = cf1;
583			iface->conf->vht_oper_centr_freq_seg1_idx = cf2;
584		}
585	} while (res);
586
587	/* Finally start CAC */
588	hostapd_set_state(iface, HAPD_IFACE_DFS);
589	wpa_printf(MSG_DEBUG, "DFS start CAC on %d MHz", iface->freq);
590	wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_CAC_START
591		"freq=%d chan=%d sec_chan=%d",
592		iface->freq,
593		iface->conf->channel, iface->conf->secondary_channel);
594	if (hostapd_start_dfs_cac(iface, iface->conf->hw_mode,
595				  iface->freq,
596				  iface->conf->channel,
597				  iface->conf->ieee80211n,
598				  iface->conf->ieee80211ac,
599				  iface->conf->secondary_channel,
600				  iface->conf->vht_oper_chwidth,
601				  iface->conf->vht_oper_centr_freq_seg0_idx,
602				  iface->conf->vht_oper_centr_freq_seg1_idx)) {
603		wpa_printf(MSG_DEBUG, "DFS start_dfs_cac() failed");
604		return -1;
605	}
606
607	return 0;
608}
609
610
611int hostapd_dfs_complete_cac(struct hostapd_iface *iface, int success, int freq,
612			     int ht_enabled, int chan_offset, int chan_width,
613			     int cf1, int cf2)
614{
615	wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_CAC_COMPLETED
616		"success=%d freq=%d ht_enabled=%d chan_offset=%d chan_width=%d cf1=%d cf2=%d",
617		success, freq, ht_enabled, chan_offset, chan_width, cf1, cf2);
618
619	if (success) {
620		/* Complete iface/ap configuration */
621		set_dfs_state(iface, freq, ht_enabled, chan_offset,
622			      chan_width, cf1, cf2,
623			      HOSTAPD_CHAN_DFS_AVAILABLE);
624		iface->cac_started = 0;
625		hostapd_setup_interface_complete(iface, 0);
626	}
627
628	return 0;
629}
630
631
632static int hostapd_dfs_start_channel_switch_cac(struct hostapd_iface *iface)
633{
634	struct hostapd_channel_data *channel;
635	int secondary_channel;
636	u8 vht_oper_centr_freq_seg0_idx = 0;
637	u8 vht_oper_centr_freq_seg1_idx = 0;
638	int skip_radar = 0;
639	int err = 1;
640
641	/* Radar detected during active CAC */
642	iface->cac_started = 0;
643	channel = dfs_get_valid_channel(iface, &secondary_channel,
644					&vht_oper_centr_freq_seg0_idx,
645					&vht_oper_centr_freq_seg1_idx,
646					skip_radar);
647
648	if (!channel) {
649		wpa_printf(MSG_ERROR, "No valid channel available");
650		hostapd_setup_interface_complete(iface, err);
651		return err;
652	}
653
654	wpa_printf(MSG_DEBUG, "DFS will switch to a new channel %d",
655		   channel->chan);
656	wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_NEW_CHANNEL
657		"freq=%d chan=%d sec_chan=%d", channel->freq,
658		channel->chan, secondary_channel);
659
660	iface->freq = channel->freq;
661	iface->conf->channel = channel->chan;
662	iface->conf->secondary_channel = secondary_channel;
663	iface->conf->vht_oper_centr_freq_seg0_idx =
664		vht_oper_centr_freq_seg0_idx;
665	iface->conf->vht_oper_centr_freq_seg1_idx =
666		vht_oper_centr_freq_seg1_idx;
667	err = 0;
668
669	hostapd_setup_interface_complete(iface, err);
670	return err;
671}
672
673
674static int hostapd_dfs_start_channel_switch(struct hostapd_iface *iface)
675{
676	struct hostapd_channel_data *channel;
677	int secondary_channel;
678	u8 vht_oper_centr_freq_seg0_idx;
679	u8 vht_oper_centr_freq_seg1_idx;
680	int skip_radar = 1;
681	struct csa_settings csa_settings;
682	struct hostapd_data *hapd = iface->bss[0];
683	int err = 1;
684
685	wpa_printf(MSG_DEBUG, "%s called (CAC active: %s, CSA active: %s)",
686		   __func__, iface->cac_started ? "yes" : "no",
687		   iface->csa_in_progress ? "yes" : "no");
688
689	/* Check if CSA in progress */
690	if (iface->csa_in_progress)
691		return 0;
692
693	/* Check if active CAC */
694	if (iface->cac_started)
695		return hostapd_dfs_start_channel_switch_cac(iface);
696
697	/* Perform channel switch/CSA */
698	channel = dfs_get_valid_channel(iface, &secondary_channel,
699					&vht_oper_centr_freq_seg0_idx,
700					&vht_oper_centr_freq_seg1_idx,
701					skip_radar);
702
703	if (!channel) {
704		/* FIXME: Wait for channel(s) to become available */
705		hostapd_disable_iface(iface);
706		return err;
707	}
708
709	wpa_printf(MSG_DEBUG, "DFS will switch to a new channel %d",
710		   channel->chan);
711	wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_NEW_CHANNEL
712		"freq=%d chan=%d sec_chan=%d", channel->freq,
713		channel->chan, secondary_channel);
714
715	/* Setup CSA request */
716	os_memset(&csa_settings, 0, sizeof(csa_settings));
717	csa_settings.cs_count = 5;
718	csa_settings.block_tx = 1;
719	err = hostapd_set_freq_params(&csa_settings.freq_params,
720				      iface->conf->hw_mode,
721				      channel->freq,
722				      channel->chan,
723				      iface->conf->ieee80211n,
724				      iface->conf->ieee80211ac,
725				      secondary_channel,
726				      iface->conf->vht_oper_chwidth,
727				      vht_oper_centr_freq_seg0_idx,
728				      vht_oper_centr_freq_seg1_idx,
729				      iface->current_mode->vht_capab);
730
731	if (err) {
732		wpa_printf(MSG_ERROR, "DFS failed to calculate CSA freq params");
733		hostapd_disable_iface(iface);
734		return err;
735	}
736
737	err = hostapd_switch_channel(hapd, &csa_settings);
738	if (err) {
739		wpa_printf(MSG_WARNING, "DFS failed to schedule CSA (%d) - trying fallback",
740			   err);
741		iface->freq = channel->freq;
742		iface->conf->channel = channel->chan;
743		iface->conf->secondary_channel = secondary_channel;
744		iface->conf->vht_oper_centr_freq_seg0_idx =
745			vht_oper_centr_freq_seg0_idx;
746		iface->conf->vht_oper_centr_freq_seg1_idx =
747			vht_oper_centr_freq_seg1_idx;
748
749		hostapd_disable_iface(iface);
750		hostapd_enable_iface(iface);
751		return 0;
752	}
753
754	/* Channel configuration will be updated once CSA completes and
755	 * ch_switch_notify event is received */
756
757	wpa_printf(MSG_DEBUG, "DFS waiting channel switch event");
758	return 0;
759}
760
761
762int hostapd_dfs_radar_detected(struct hostapd_iface *iface, int freq,
763			       int ht_enabled, int chan_offset, int chan_width,
764			       int cf1, int cf2)
765{
766	int res;
767
768	if (!iface->conf->ieee80211h)
769		return 0;
770
771	wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_RADAR_DETECTED
772		"freq=%d ht_enabled=%d chan_offset=%d chan_width=%d cf1=%d cf2=%d",
773		freq, ht_enabled, chan_offset, chan_width, cf1, cf2);
774
775	/* mark radar frequency as invalid */
776	res = set_dfs_state(iface, freq, ht_enabled, chan_offset,
777			    chan_width, cf1, cf2,
778			    HOSTAPD_CHAN_DFS_UNAVAILABLE);
779
780	/* Skip if reported radar event not overlapped our channels */
781	res = dfs_are_channels_overlapped(iface, freq, chan_width, cf1, cf2);
782	if (!res)
783		return 0;
784
785	/* radar detected while operating, switch the channel. */
786	res = hostapd_dfs_start_channel_switch(iface);
787
788	return res;
789}
790
791
792int hostapd_dfs_nop_finished(struct hostapd_iface *iface, int freq,
793			     int ht_enabled, int chan_offset, int chan_width,
794			     int cf1, int cf2)
795{
796	wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_NOP_FINISHED
797		"freq=%d ht_enabled=%d chan_offset=%d chan_width=%d cf1=%d cf2=%d",
798		freq, ht_enabled, chan_offset, chan_width, cf1, cf2);
799	/* TODO add correct implementation here */
800	set_dfs_state(iface, freq, ht_enabled, chan_offset, chan_width,
801		      cf1, cf2, HOSTAPD_CHAN_DFS_USABLE);
802	return 0;
803}
804