2 * DFS - Dynamic Frequency Selection
3 * Copyright (c) 2002-2013, Jouni Malinen <j@w1.fi>
4 * Copyright (c) 2013-2015, Qualcomm Atheros, Inc.
6 * This software may be distributed under the terms of the BSD license.
7 * See README for more details.
10 #include "utils/includes.h"
12 #include "utils/common.h"
13 #include "common/ieee802_11_defs.h"
14 #include "common/hw_features_common.h"
15 #include "common/wpa_ctrl.h"
17 #include "ap_drv_ops.h"
18 #include "drivers/driver.h"
22 static int dfs_get_used_n_chans(struct hostapd_iface *iface, int *seg1)
28 if (iface->conf->ieee80211n && iface->conf->secondary_channel)
31 if (iface->conf->ieee80211ac) {
32 switch (iface->conf->vht_oper_chwidth) {
33 case VHT_CHANWIDTH_USE_HT:
35 case VHT_CHANWIDTH_80MHZ:
38 case VHT_CHANWIDTH_160MHZ:
41 case VHT_CHANWIDTH_80P80MHZ:
54 static int dfs_channel_available(struct hostapd_channel_data *chan,
58 * When radar detection happens, CSA is performed. However, there's no
59 * time for CAC, so radar channels must be skipped when finding a new
60 * channel for CSA, unless they are available for immediate use.
62 if (skip_radar && (chan->flag & HOSTAPD_CHAN_RADAR) &&
63 ((chan->flag & HOSTAPD_CHAN_DFS_MASK) !=
64 HOSTAPD_CHAN_DFS_AVAILABLE))
67 if (chan->flag & HOSTAPD_CHAN_DISABLED)
69 if ((chan->flag & HOSTAPD_CHAN_RADAR) &&
70 ((chan->flag & HOSTAPD_CHAN_DFS_MASK) ==
71 HOSTAPD_CHAN_DFS_UNAVAILABLE))
77 static int dfs_is_chan_allowed(struct hostapd_channel_data *chan, int n_chans)
80 * The tables contain first valid channel number based on channel width.
81 * We will also choose this first channel as the control one.
83 int allowed_40[] = { 36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157,
86 * VHT80, valid channels based on center frequency:
87 * 42, 58, 106, 122, 138, 155
89 int allowed_80[] = { 36, 52, 100, 116, 132, 149 };
91 * VHT160 valid channels based on center frequency:
94 int allowed_160[] = { 36, 100 };
95 int *allowed = allowed_40;
96 unsigned int i, allowed_no = 0;
100 allowed = allowed_40;
101 allowed_no = ARRAY_SIZE(allowed_40);
104 allowed = allowed_80;
105 allowed_no = ARRAY_SIZE(allowed_80);
108 allowed = allowed_160;
109 allowed_no = ARRAY_SIZE(allowed_160);
112 wpa_printf(MSG_DEBUG, "Unknown width for %d channels", n_chans);
116 for (i = 0; i < allowed_no; i++) {
117 if (chan->chan == allowed[i])
125 static struct hostapd_channel_data *
126 dfs_get_chan_data(struct hostapd_hw_modes *mode, int freq, int first_chan_idx)
130 for (i = first_chan_idx; i < mode->num_channels; i++) {
131 if (mode->channels[i].freq == freq)
132 return &mode->channels[i];
139 static int dfs_chan_range_available(struct hostapd_hw_modes *mode,
140 int first_chan_idx, int num_chans,
143 struct hostapd_channel_data *first_chan, *chan;
146 if (first_chan_idx + num_chans > mode->num_channels)
149 first_chan = &mode->channels[first_chan_idx];
151 for (i = 0; i < num_chans; i++) {
152 chan = dfs_get_chan_data(mode, first_chan->freq + i * 20,
157 if (!dfs_channel_available(chan, skip_radar))
165 static int is_in_chanlist(struct hostapd_iface *iface,
166 struct hostapd_channel_data *chan)
168 if (!iface->conf->acs_ch_list.num)
171 return freq_range_list_includes(&iface->conf->acs_ch_list, chan->chan);
176 * The function assumes HT40+ operation.
177 * Make sure to adjust the following variables after calling this:
178 * - hapd->secondary_channel
179 * - hapd->vht_oper_centr_freq_seg0_idx
180 * - hapd->vht_oper_centr_freq_seg1_idx
182 static int dfs_find_channel(struct hostapd_iface *iface,
183 struct hostapd_channel_data **ret_chan,
184 int idx, int skip_radar)
186 struct hostapd_hw_modes *mode;
187 struct hostapd_channel_data *chan;
188 int i, channel_idx = 0, n_chans, n_chans1;
190 mode = iface->current_mode;
191 n_chans = dfs_get_used_n_chans(iface, &n_chans1);
193 wpa_printf(MSG_DEBUG, "DFS new chan checking %d channels", n_chans);
194 for (i = 0; i < mode->num_channels; i++) {
195 chan = &mode->channels[i];
197 /* Skip HT40/VHT incompatible channels */
198 if (iface->conf->ieee80211n &&
199 iface->conf->secondary_channel &&
200 !dfs_is_chan_allowed(chan, n_chans))
203 /* Skip incompatible chandefs */
204 if (!dfs_chan_range_available(mode, i, n_chans, skip_radar))
207 if (!is_in_chanlist(iface, chan))
210 if (ret_chan && idx == channel_idx) {
211 wpa_printf(MSG_DEBUG, "Selected ch. #%d", chan->chan);
215 wpa_printf(MSG_DEBUG, "Adding channel: %d", chan->chan);
222 static void dfs_adjust_vht_center_freq(struct hostapd_iface *iface,
223 struct hostapd_channel_data *chan,
224 int secondary_channel,
225 u8 *vht_oper_centr_freq_seg0_idx,
226 u8 *vht_oper_centr_freq_seg1_idx)
228 if (!iface->conf->ieee80211ac)
234 *vht_oper_centr_freq_seg1_idx = 0;
236 switch (iface->conf->vht_oper_chwidth) {
237 case VHT_CHANWIDTH_USE_HT:
238 if (secondary_channel == 1)
239 *vht_oper_centr_freq_seg0_idx = chan->chan + 2;
240 else if (secondary_channel == -1)
241 *vht_oper_centr_freq_seg0_idx = chan->chan - 2;
243 *vht_oper_centr_freq_seg0_idx = chan->chan;
245 case VHT_CHANWIDTH_80MHZ:
246 *vht_oper_centr_freq_seg0_idx = chan->chan + 6;
248 case VHT_CHANWIDTH_160MHZ:
249 *vht_oper_centr_freq_seg0_idx = chan->chan + 14;
252 wpa_printf(MSG_INFO, "DFS only VHT20/40/80/160 is supported now");
253 *vht_oper_centr_freq_seg0_idx = 0;
257 wpa_printf(MSG_DEBUG, "DFS adjusting VHT center frequency: %d, %d",
258 *vht_oper_centr_freq_seg0_idx,
259 *vht_oper_centr_freq_seg1_idx);
263 /* Return start channel idx we will use for mode->channels[idx] */
264 static int dfs_get_start_chan_idx(struct hostapd_iface *iface, int *seg1_start)
266 struct hostapd_hw_modes *mode;
267 struct hostapd_channel_data *chan;
268 int channel_no = iface->conf->channel;
275 if (iface->conf->ieee80211n && iface->conf->secondary_channel == -1)
279 if (iface->conf->ieee80211ac) {
280 switch (iface->conf->vht_oper_chwidth) {
281 case VHT_CHANWIDTH_USE_HT:
283 case VHT_CHANWIDTH_80MHZ:
285 iface->conf->vht_oper_centr_freq_seg0_idx - 6;
287 case VHT_CHANWIDTH_160MHZ:
289 iface->conf->vht_oper_centr_freq_seg0_idx - 14;
291 case VHT_CHANWIDTH_80P80MHZ:
293 iface->conf->vht_oper_centr_freq_seg0_idx - 6;
295 iface->conf->vht_oper_centr_freq_seg1_idx - 6;
299 "DFS only VHT20/40/80/160/80+80 is supported now");
306 mode = iface->current_mode;
307 for (i = 0; i < mode->num_channels; i++) {
308 chan = &mode->channels[i];
309 if (chan->chan == channel_no) {
315 if (res != -1 && chan_seg1 > -1) {
318 /* Get idx for seg1 */
319 mode = iface->current_mode;
320 for (i = 0; i < mode->num_channels; i++) {
321 chan = &mode->channels[i];
322 if (chan->chan == chan_seg1) {
333 wpa_printf(MSG_DEBUG,
334 "DFS chan_idx seems wrong; num-ch: %d ch-no: %d conf-ch-no: %d 11n: %d sec-ch: %d vht-oper-width: %d",
335 mode->num_channels, channel_no, iface->conf->channel,
336 iface->conf->ieee80211n,
337 iface->conf->secondary_channel,
338 iface->conf->vht_oper_chwidth);
340 for (i = 0; i < mode->num_channels; i++) {
341 wpa_printf(MSG_DEBUG, "Available channel: %d",
342 mode->channels[i].chan);
350 /* At least one channel have radar flag */
351 static int dfs_check_chans_radar(struct hostapd_iface *iface,
352 int start_chan_idx, int n_chans)
354 struct hostapd_channel_data *channel;
355 struct hostapd_hw_modes *mode;
358 mode = iface->current_mode;
360 for (i = 0; i < n_chans; i++) {
361 channel = &mode->channels[start_chan_idx + i];
362 if (channel->flag & HOSTAPD_CHAN_RADAR)
370 /* All channels available */
371 static int dfs_check_chans_available(struct hostapd_iface *iface,
372 int start_chan_idx, int n_chans)
374 struct hostapd_channel_data *channel;
375 struct hostapd_hw_modes *mode;
378 mode = iface->current_mode;
380 for (i = 0; i < n_chans; i++) {
381 channel = &mode->channels[start_chan_idx + i];
383 if (channel->flag & HOSTAPD_CHAN_DISABLED)
386 if (!(channel->flag & HOSTAPD_CHAN_RADAR))
389 if ((channel->flag & HOSTAPD_CHAN_DFS_MASK) !=
390 HOSTAPD_CHAN_DFS_AVAILABLE)
398 /* At least one channel unavailable */
399 static int dfs_check_chans_unavailable(struct hostapd_iface *iface,
403 struct hostapd_channel_data *channel;
404 struct hostapd_hw_modes *mode;
407 mode = iface->current_mode;
409 for (i = 0; i < n_chans; i++) {
410 channel = &mode->channels[start_chan_idx + i];
411 if (channel->flag & HOSTAPD_CHAN_DISABLED)
413 if ((channel->flag & HOSTAPD_CHAN_DFS_MASK) ==
414 HOSTAPD_CHAN_DFS_UNAVAILABLE)
422 static struct hostapd_channel_data *
423 dfs_get_valid_channel(struct hostapd_iface *iface,
424 int *secondary_channel,
425 u8 *vht_oper_centr_freq_seg0_idx,
426 u8 *vht_oper_centr_freq_seg1_idx,
429 struct hostapd_hw_modes *mode;
430 struct hostapd_channel_data *chan = NULL;
431 int num_available_chandefs;
435 wpa_printf(MSG_DEBUG, "DFS: Selecting random channel");
436 *secondary_channel = 0;
437 *vht_oper_centr_freq_seg0_idx = 0;
438 *vht_oper_centr_freq_seg1_idx = 0;
440 if (iface->current_mode == NULL)
443 mode = iface->current_mode;
444 if (mode->mode != HOSTAPD_MODE_IEEE80211A)
447 /* Get the count first */
448 num_available_chandefs = dfs_find_channel(iface, NULL, 0, skip_radar);
449 if (num_available_chandefs == 0)
452 if (os_get_random((u8 *) &_rand, sizeof(_rand)) < 0)
454 chan_idx = _rand % num_available_chandefs;
455 dfs_find_channel(iface, &chan, chan_idx, skip_radar);
457 /* dfs_find_channel() calculations assume HT40+ */
458 if (iface->conf->secondary_channel)
459 *secondary_channel = 1;
461 *secondary_channel = 0;
463 dfs_adjust_vht_center_freq(iface, chan,
465 vht_oper_centr_freq_seg0_idx,
466 vht_oper_centr_freq_seg1_idx);
472 static int set_dfs_state_freq(struct hostapd_iface *iface, int freq, u32 state)
474 struct hostapd_hw_modes *mode;
475 struct hostapd_channel_data *chan = NULL;
478 mode = iface->current_mode;
482 wpa_printf(MSG_DEBUG, "set_dfs_state 0x%X for %d MHz", state, freq);
483 for (i = 0; i < iface->current_mode->num_channels; i++) {
484 chan = &iface->current_mode->channels[i];
485 if (chan->freq == freq) {
486 if (chan->flag & HOSTAPD_CHAN_RADAR) {
487 chan->flag &= ~HOSTAPD_CHAN_DFS_MASK;
489 return 1; /* Channel found */
493 wpa_printf(MSG_WARNING, "Can't set DFS state for freq %d MHz", freq);
498 static int set_dfs_state(struct hostapd_iface *iface, int freq, int ht_enabled,
499 int chan_offset, int chan_width, int cf1,
503 struct hostapd_hw_modes *mode;
504 int frequency = freq;
507 mode = iface->current_mode;
511 if (mode->mode != HOSTAPD_MODE_IEEE80211A) {
512 wpa_printf(MSG_WARNING, "current_mode != IEEE80211A");
516 /* Seems cf1 and chan_width is enough here */
517 switch (chan_width) {
518 case CHAN_WIDTH_20_NOHT:
526 frequency = cf1 - 10;
530 frequency = cf1 - 30;
534 frequency = cf1 - 70;
537 wpa_printf(MSG_INFO, "DFS chan_width %d not supported",
542 wpa_printf(MSG_DEBUG, "DFS freq: %dMHz, n_chans: %d", frequency,
544 for (i = 0; i < n_chans; i++) {
545 ret += set_dfs_state_freq(iface, frequency, state);
546 frequency = frequency + 20;
553 static int dfs_are_channels_overlapped(struct hostapd_iface *iface, int freq,
554 int chan_width, int cf1, int cf2)
556 int start_chan_idx, start_chan_idx1;
557 struct hostapd_hw_modes *mode;
558 struct hostapd_channel_data *chan;
559 int n_chans, n_chans1, i, j, frequency = freq, radar_n_chans = 1;
563 /* Our configuration */
564 mode = iface->current_mode;
565 start_chan_idx = dfs_get_start_chan_idx(iface, &start_chan_idx1);
566 n_chans = dfs_get_used_n_chans(iface, &n_chans1);
568 /* Check we are on DFS channel(s) */
569 if (!dfs_check_chans_radar(iface, start_chan_idx, n_chans))
572 /* Reported via radar event */
573 switch (chan_width) {
574 case CHAN_WIDTH_20_NOHT:
582 frequency = cf1 - 10;
586 frequency = cf1 - 30;
590 frequency = cf1 - 70;
593 wpa_printf(MSG_INFO, "DFS chan_width %d not supported",
598 ieee80211_freq_to_chan(frequency, &radar_chan);
600 for (i = 0; i < n_chans; i++) {
601 chan = &mode->channels[start_chan_idx + i];
602 if (!(chan->flag & HOSTAPD_CHAN_RADAR))
604 for (j = 0; j < radar_n_chans; j++) {
605 wpa_printf(MSG_DEBUG, "checking our: %d, radar: %d",
606 chan->chan, radar_chan + j * 4);
607 if (chan->chan == radar_chan + j * 4)
612 wpa_printf(MSG_DEBUG, "overlapped: %d", res);
618 static unsigned int dfs_get_cac_time(struct hostapd_iface *iface,
619 int start_chan_idx, int n_chans)
621 struct hostapd_channel_data *channel;
622 struct hostapd_hw_modes *mode;
624 unsigned int cac_time_ms = 0;
626 mode = iface->current_mode;
628 for (i = 0; i < n_chans; i++) {
629 channel = &mode->channels[start_chan_idx + i];
630 if (!(channel->flag & HOSTAPD_CHAN_RADAR))
632 if (channel->dfs_cac_ms > cac_time_ms)
633 cac_time_ms = channel->dfs_cac_ms;
642 * 1 - continue channel/ap setup
643 * 0 - channel/ap setup will be continued after CAC
644 * -1 - hit critical error
646 int hostapd_handle_dfs(struct hostapd_iface *iface)
648 struct hostapd_channel_data *channel;
649 int res, n_chans, n_chans1, start_chan_idx, start_chan_idx1;
652 if (!iface->current_mode) {
654 * This can happen with drivers that do not provide mode
655 * information and as such, cannot really use hostapd for DFS.
657 wpa_printf(MSG_DEBUG,
658 "DFS: No current_mode information - assume no need to perform DFS operations by hostapd");
662 iface->cac_started = 0;
665 /* Get start (first) channel for current configuration */
666 start_chan_idx = dfs_get_start_chan_idx(iface,
668 if (start_chan_idx == -1)
671 /* Get number of used channels, depend on width */
672 n_chans = dfs_get_used_n_chans(iface, &n_chans1);
675 iface->dfs_cac_ms = dfs_get_cac_time(iface, start_chan_idx,
678 /* Check if any of configured channels require DFS */
679 res = dfs_check_chans_radar(iface, start_chan_idx, n_chans);
680 wpa_printf(MSG_DEBUG,
681 "DFS %d channels required radar detection",
686 /* Check if all channels are DFS available */
687 res = dfs_check_chans_available(iface, start_chan_idx, n_chans);
688 wpa_printf(MSG_DEBUG,
689 "DFS all channels available, (SKIP CAC): %s",
694 /* Check if any of configured channels is unavailable */
695 res = dfs_check_chans_unavailable(iface, start_chan_idx,
697 wpa_printf(MSG_DEBUG, "DFS %d chans unavailable - choose other channel: %s",
698 res, res ? "yes": "no");
703 channel = dfs_get_valid_channel(iface, &sec, &cf1, &cf2,
706 wpa_printf(MSG_ERROR, "could not get valid channel");
710 iface->freq = channel->freq;
711 iface->conf->channel = channel->chan;
712 iface->conf->secondary_channel = sec;
713 iface->conf->vht_oper_centr_freq_seg0_idx = cf1;
714 iface->conf->vht_oper_centr_freq_seg1_idx = cf2;
718 /* Finally start CAC */
719 hostapd_set_state(iface, HAPD_IFACE_DFS);
720 wpa_printf(MSG_DEBUG, "DFS start CAC on %d MHz", iface->freq);
721 wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_CAC_START
722 "freq=%d chan=%d sec_chan=%d, width=%d, seg0=%d, seg1=%d, cac_time=%ds",
724 iface->conf->channel, iface->conf->secondary_channel,
725 iface->conf->vht_oper_chwidth,
726 iface->conf->vht_oper_centr_freq_seg0_idx,
727 iface->conf->vht_oper_centr_freq_seg1_idx,
728 iface->dfs_cac_ms / 1000);
730 res = hostapd_start_dfs_cac(iface, iface->conf->hw_mode,
732 iface->conf->channel,
733 iface->conf->ieee80211n,
734 iface->conf->ieee80211ac,
735 iface->conf->secondary_channel,
736 iface->conf->vht_oper_chwidth,
737 iface->conf->vht_oper_centr_freq_seg0_idx,
738 iface->conf->vht_oper_centr_freq_seg1_idx);
741 wpa_printf(MSG_ERROR, "DFS start_dfs_cac() failed, %d", res);
749 int hostapd_dfs_complete_cac(struct hostapd_iface *iface, int success, int freq,
750 int ht_enabled, int chan_offset, int chan_width,
753 wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_CAC_COMPLETED
754 "success=%d freq=%d ht_enabled=%d chan_offset=%d chan_width=%d cf1=%d cf2=%d",
755 success, freq, ht_enabled, chan_offset, chan_width, cf1, cf2);
758 /* Complete iface/ap configuration */
759 if (iface->drv_flags & WPA_DRIVER_FLAGS_DFS_OFFLOAD) {
760 /* Complete AP configuration for the first bring up. */
761 if (iface->state != HAPD_IFACE_ENABLED)
762 hostapd_setup_interface_complete(iface, 0);
764 iface->cac_started = 0;
766 set_dfs_state(iface, freq, ht_enabled, chan_offset,
767 chan_width, cf1, cf2,
768 HOSTAPD_CHAN_DFS_AVAILABLE);
769 iface->cac_started = 0;
770 hostapd_setup_interface_complete(iface, 0);
778 static int hostapd_dfs_start_channel_switch_cac(struct hostapd_iface *iface)
780 struct hostapd_channel_data *channel;
781 int secondary_channel;
782 u8 vht_oper_centr_freq_seg0_idx = 0;
783 u8 vht_oper_centr_freq_seg1_idx = 0;
787 /* Radar detected during active CAC */
788 iface->cac_started = 0;
789 channel = dfs_get_valid_channel(iface, &secondary_channel,
790 &vht_oper_centr_freq_seg0_idx,
791 &vht_oper_centr_freq_seg1_idx,
795 wpa_printf(MSG_ERROR, "No valid channel available");
796 hostapd_setup_interface_complete(iface, err);
800 wpa_printf(MSG_DEBUG, "DFS will switch to a new channel %d",
802 wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_NEW_CHANNEL
803 "freq=%d chan=%d sec_chan=%d", channel->freq,
804 channel->chan, secondary_channel);
806 iface->freq = channel->freq;
807 iface->conf->channel = channel->chan;
808 iface->conf->secondary_channel = secondary_channel;
809 iface->conf->vht_oper_centr_freq_seg0_idx =
810 vht_oper_centr_freq_seg0_idx;
811 iface->conf->vht_oper_centr_freq_seg1_idx =
812 vht_oper_centr_freq_seg1_idx;
815 hostapd_setup_interface_complete(iface, err);
820 static int hostapd_csa_in_progress(struct hostapd_iface *iface)
823 for (i = 0; i < iface->num_bss; i++)
824 if (iface->bss[i]->csa_in_progress)
830 static int hostapd_dfs_start_channel_switch(struct hostapd_iface *iface)
832 struct hostapd_channel_data *channel;
833 int secondary_channel;
834 u8 vht_oper_centr_freq_seg0_idx;
835 u8 vht_oper_centr_freq_seg1_idx;
837 struct csa_settings csa_settings;
841 wpa_printf(MSG_DEBUG, "%s called (CAC active: %s, CSA active: %s)",
842 __func__, iface->cac_started ? "yes" : "no",
843 hostapd_csa_in_progress(iface) ? "yes" : "no");
845 /* Check if CSA in progress */
846 if (hostapd_csa_in_progress(iface))
849 /* Check if active CAC */
850 if (iface->cac_started)
851 return hostapd_dfs_start_channel_switch_cac(iface);
853 /* Perform channel switch/CSA */
854 channel = dfs_get_valid_channel(iface, &secondary_channel,
855 &vht_oper_centr_freq_seg0_idx,
856 &vht_oper_centr_freq_seg1_idx,
861 * If there is no channel to switch immediately to, check if
862 * there is another channel where we can switch even if it
863 * requires to perform a CAC first.
866 channel = dfs_get_valid_channel(iface, &secondary_channel,
867 &vht_oper_centr_freq_seg0_idx,
868 &vht_oper_centr_freq_seg1_idx,
871 /* FIXME: Wait for channel(s) to become available */
872 hostapd_disable_iface(iface);
876 iface->freq = channel->freq;
877 iface->conf->channel = channel->chan;
878 iface->conf->secondary_channel = secondary_channel;
879 iface->conf->vht_oper_centr_freq_seg0_idx =
880 vht_oper_centr_freq_seg0_idx;
881 iface->conf->vht_oper_centr_freq_seg1_idx =
882 vht_oper_centr_freq_seg1_idx;
884 hostapd_disable_iface(iface);
885 hostapd_enable_iface(iface);
889 wpa_printf(MSG_DEBUG, "DFS will switch to a new channel %d",
891 wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_NEW_CHANNEL
892 "freq=%d chan=%d sec_chan=%d", channel->freq,
893 channel->chan, secondary_channel);
895 /* Setup CSA request */
896 os_memset(&csa_settings, 0, sizeof(csa_settings));
897 csa_settings.cs_count = 5;
898 csa_settings.block_tx = 1;
899 err = hostapd_set_freq_params(&csa_settings.freq_params,
900 iface->conf->hw_mode,
903 iface->conf->ieee80211n,
904 iface->conf->ieee80211ac,
906 iface->conf->vht_oper_chwidth,
907 vht_oper_centr_freq_seg0_idx,
908 vht_oper_centr_freq_seg1_idx,
909 iface->current_mode->vht_capab);
912 wpa_printf(MSG_ERROR, "DFS failed to calculate CSA freq params");
913 hostapd_disable_iface(iface);
917 for (i = 0; i < iface->num_bss; i++) {
918 err = hostapd_switch_channel(iface->bss[i], &csa_settings);
924 wpa_printf(MSG_WARNING, "DFS failed to schedule CSA (%d) - trying fallback",
926 iface->freq = channel->freq;
927 iface->conf->channel = channel->chan;
928 iface->conf->secondary_channel = secondary_channel;
929 iface->conf->vht_oper_centr_freq_seg0_idx =
930 vht_oper_centr_freq_seg0_idx;
931 iface->conf->vht_oper_centr_freq_seg1_idx =
932 vht_oper_centr_freq_seg1_idx;
934 hostapd_disable_iface(iface);
935 hostapd_enable_iface(iface);
939 /* Channel configuration will be updated once CSA completes and
940 * ch_switch_notify event is received */
942 wpa_printf(MSG_DEBUG, "DFS waiting channel switch event");
947 int hostapd_dfs_radar_detected(struct hostapd_iface *iface, int freq,
948 int ht_enabled, int chan_offset, int chan_width,
953 wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_RADAR_DETECTED
954 "freq=%d ht_enabled=%d chan_offset=%d chan_width=%d cf1=%d cf2=%d",
955 freq, ht_enabled, chan_offset, chan_width, cf1, cf2);
957 /* Proceed only if DFS is not offloaded to the driver */
958 if (iface->drv_flags & WPA_DRIVER_FLAGS_DFS_OFFLOAD)
961 if (!iface->conf->ieee80211h)
964 /* mark radar frequency as invalid */
965 set_dfs_state(iface, freq, ht_enabled, chan_offset, chan_width,
966 cf1, cf2, HOSTAPD_CHAN_DFS_UNAVAILABLE);
968 /* Skip if reported radar event not overlapped our channels */
969 res = dfs_are_channels_overlapped(iface, freq, chan_width, cf1, cf2);
973 /* radar detected while operating, switch the channel. */
974 res = hostapd_dfs_start_channel_switch(iface);
980 int hostapd_dfs_nop_finished(struct hostapd_iface *iface, int freq,
981 int ht_enabled, int chan_offset, int chan_width,
984 wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_NOP_FINISHED
985 "freq=%d ht_enabled=%d chan_offset=%d chan_width=%d cf1=%d cf2=%d",
986 freq, ht_enabled, chan_offset, chan_width, cf1, cf2);
988 /* Proceed only if DFS is not offloaded to the driver */
989 if (iface->drv_flags & WPA_DRIVER_FLAGS_DFS_OFFLOAD)
992 /* TODO add correct implementation here */
993 set_dfs_state(iface, freq, ht_enabled, chan_offset, chan_width,
994 cf1, cf2, HOSTAPD_CHAN_DFS_USABLE);
999 int hostapd_is_dfs_required(struct hostapd_iface *iface)
1001 int n_chans, n_chans1, start_chan_idx, start_chan_idx1, res;
1003 if (!iface->conf->ieee80211h || !iface->current_mode ||
1004 iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A)
1007 /* Get start (first) channel for current configuration */
1008 start_chan_idx = dfs_get_start_chan_idx(iface, &start_chan_idx1);
1009 if (start_chan_idx == -1)
1012 /* Get number of used channels, depend on width */
1013 n_chans = dfs_get_used_n_chans(iface, &n_chans1);
1015 /* Check if any of configured channels require DFS */
1016 res = dfs_check_chans_radar(iface, start_chan_idx, n_chans);
1019 if (start_chan_idx1 >= 0 && n_chans1 > 0)
1020 res = dfs_check_chans_radar(iface, start_chan_idx1, n_chans1);
1025 int hostapd_dfs_start_cac(struct hostapd_iface *iface, int freq,
1026 int ht_enabled, int chan_offset, int chan_width,
1029 wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_CAC_START
1030 "freq=%d chan=%d chan_offset=%d width=%d seg0=%d "
1031 "seg1=%d cac_time=%ds",
1032 freq, (freq - 5000) / 5, chan_offset, chan_width, cf1, cf2, 60);
1033 iface->cac_started = 1;
1039 * Main DFS handler for offloaded case.
1040 * 2 - continue channel/AP setup for non-DFS channel
1041 * 1 - continue channel/AP setup for DFS channel
1042 * 0 - channel/AP setup will be continued after CAC
1043 * -1 - hit critical error
1045 int hostapd_handle_dfs_offload(struct hostapd_iface *iface)
1047 wpa_printf(MSG_DEBUG, "%s: iface->cac_started: %d",
1048 __func__, iface->cac_started);
1051 * If DFS has already been started, then we are being called from a
1052 * callback to continue AP/channel setup. Reset the CAC start flag and
1055 if (iface->cac_started) {
1056 wpa_printf(MSG_DEBUG, "%s: iface->cac_started: %d",
1057 __func__, iface->cac_started);
1058 iface->cac_started = 0;
1062 if (ieee80211_is_dfs(iface->freq)) {
1063 wpa_printf(MSG_DEBUG, "%s: freq %d MHz requires DFS",
1064 __func__, iface->freq);
1068 wpa_printf(MSG_DEBUG,
1069 "%s: freq %d MHz does not require DFS. Continue channel/AP setup",
1070 __func__, iface->freq);