automake build system
[mech_eap.orig] / src / ap / hw_features.c
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) 2008-2009, 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 static int hostapd_prepare_rates(struct hostapd_data *hapd,
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 (hapd->iconf->basic_rates)
114                 basic_rates = hapd->iconf->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         default:
126                 return -1;
127         }
128
129         if (hostapd_set_rate_sets(hapd, hapd->iconf->supported_rates,
130                                   basic_rates, mode->mode)) {
131                 wpa_printf(MSG_ERROR, "Failed to update rate sets in kernel "
132                            "module");
133         }
134
135         os_free(hapd->iface->current_rates);
136         hapd->iface->num_rates = 0;
137
138         hapd->iface->current_rates =
139                 os_zalloc(mode->num_rates * sizeof(struct hostapd_rate_data));
140         if (!hapd->iface->current_rates) {
141                 wpa_printf(MSG_ERROR, "Failed to allocate memory for rate "
142                            "table.");
143                 return -1;
144         }
145
146         for (i = 0; i < mode->num_rates; i++) {
147                 struct hostapd_rate_data *rate;
148
149                 if (hapd->iconf->supported_rates &&
150                     !hostapd_rate_found(hapd->iconf->supported_rates,
151                                         mode->rates[i]))
152                         continue;
153
154                 rate = &hapd->iface->current_rates[hapd->iface->num_rates];
155                 rate->rate = mode->rates[i];
156                 if (hostapd_rate_found(basic_rates, rate->rate)) {
157                         rate->flags |= HOSTAPD_RATE_BASIC;
158                         num_basic_rates++;
159                 }
160                 wpa_printf(MSG_DEBUG, "RATE[%d] rate=%d flags=0x%x",
161                            hapd->iface->num_rates, rate->rate, rate->flags);
162                 hapd->iface->num_rates++;
163         }
164
165         if (hapd->iface->num_rates == 0 || num_basic_rates == 0) {
166                 wpa_printf(MSG_ERROR, "No rates remaining in supported/basic "
167                            "rate sets (%d,%d).",
168                            hapd->iface->num_rates, num_basic_rates);
169                 return -1;
170         }
171
172         return 0;
173 }
174
175
176 #ifdef CONFIG_IEEE80211N
177 static int ieee80211n_allowed_ht40_channel_pair(struct hostapd_iface *iface)
178 {
179         int sec_chan, ok, j, first;
180         int allowed[] = { 36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157,
181                           184, 192 };
182         size_t k;
183
184         if (!iface->conf->secondary_channel)
185                 return 1; /* HT40 not used */
186
187         sec_chan = iface->conf->channel + iface->conf->secondary_channel * 4;
188         wpa_printf(MSG_DEBUG, "HT40: control channel: %d  "
189                    "secondary channel: %d",
190                    iface->conf->channel, sec_chan);
191
192         /* Verify that HT40 secondary channel is an allowed 20 MHz
193          * channel */
194         ok = 0;
195         for (j = 0; j < iface->current_mode->num_channels; j++) {
196                 struct hostapd_channel_data *chan =
197                         &iface->current_mode->channels[j];
198                 if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
199                     chan->chan == sec_chan) {
200                         ok = 1;
201                         break;
202                 }
203         }
204         if (!ok) {
205                 wpa_printf(MSG_ERROR, "HT40 secondary channel %d not allowed",
206                            sec_chan);
207                 return 0;
208         }
209
210         /*
211          * Verify that HT40 primary,secondary channel pair is allowed per
212          * IEEE 802.11n Annex J. This is only needed for 5 GHz band since
213          * 2.4 GHz rules allow all cases where the secondary channel fits into
214          * the list of allowed channels (already checked above).
215          */
216         if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A)
217                 return 1;
218
219         if (iface->conf->secondary_channel > 0)
220                 first = iface->conf->channel;
221         else
222                 first = sec_chan;
223
224         ok = 0;
225         for (k = 0; k < sizeof(allowed) / sizeof(allowed[0]); k++) {
226                 if (first == allowed[k]) {
227                         ok = 1;
228                         break;
229                 }
230         }
231         if (!ok) {
232                 wpa_printf(MSG_ERROR, "HT40 channel pair (%d, %d) not allowed",
233                            iface->conf->channel,
234                            iface->conf->secondary_channel);
235                 return 0;
236         }
237
238         return 1;
239 }
240
241
242 static void ieee80211n_switch_pri_sec(struct hostapd_iface *iface)
243 {
244         if (iface->conf->secondary_channel > 0) {
245                 iface->conf->channel += 4;
246                 iface->conf->secondary_channel = -1;
247         } else {
248                 iface->conf->channel -= 4;
249                 iface->conf->secondary_channel = 1;
250         }
251 }
252
253
254 static void ieee80211n_get_pri_sec_chan(struct wpa_scan_res *bss,
255                                         int *pri_chan, int *sec_chan)
256 {
257         struct ieee80211_ht_operation *oper;
258         struct ieee802_11_elems elems;
259
260         *pri_chan = *sec_chan = 0;
261
262         ieee802_11_parse_elems((u8 *) (bss + 1), bss->ie_len, &elems, 0);
263         if (elems.ht_operation &&
264             elems.ht_operation_len >= sizeof(*oper)) {
265                 oper = (struct ieee80211_ht_operation *) elems.ht_operation;
266                 *pri_chan = oper->control_chan;
267                 if (oper->ht_param & HT_INFO_HT_PARAM_REC_TRANS_CHNL_WIDTH) {
268                         int sec = oper->ht_param &
269                                 HT_INFO_HT_PARAM_SECONDARY_CHNL_OFF_MASK;
270                         if (sec == HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE)
271                                 *sec_chan = *pri_chan + 4;
272                         else if (sec == HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW)
273                                 *sec_chan = *pri_chan - 4;
274                 }
275         }
276 }
277
278
279 static int ieee80211n_check_40mhz_5g(struct hostapd_iface *iface,
280                                      struct wpa_scan_results *scan_res)
281 {
282         int pri_chan, sec_chan, pri_freq, sec_freq, pri_bss, sec_bss;
283         int bss_pri_chan, bss_sec_chan;
284         size_t i;
285         int match;
286
287         pri_chan = iface->conf->channel;
288         sec_chan = iface->conf->secondary_channel * 4;
289         pri_freq = hostapd_hw_get_freq(iface->bss[0], pri_chan);
290         if (iface->conf->secondary_channel > 0)
291                 sec_freq = pri_freq + 20;
292         else
293                 sec_freq = pri_freq - 20;
294
295         /*
296          * Switch PRI/SEC channels if Beacons were detected on selected SEC
297          * channel, but not on selected PRI channel.
298          */
299         pri_bss = sec_bss = 0;
300         for (i = 0; i < scan_res->num; i++) {
301                 struct wpa_scan_res *bss = scan_res->res[i];
302                 if (bss->freq == pri_freq)
303                         pri_bss++;
304                 else if (bss->freq == sec_freq)
305                         sec_bss++;
306         }
307         if (sec_bss && !pri_bss) {
308                 wpa_printf(MSG_INFO, "Switch own primary and secondary "
309                            "channel to get secondary channel with no Beacons "
310                            "from other BSSes");
311                 ieee80211n_switch_pri_sec(iface);
312         }
313
314         /*
315          * Match PRI/SEC channel with any existing HT40 BSS on the same
316          * channels that we are about to use (if already mixed order in
317          * existing BSSes, use own preference).
318          */
319         match = 0;
320         for (i = 0; i < scan_res->num; i++) {
321                 struct wpa_scan_res *bss = scan_res->res[i];
322                 ieee80211n_get_pri_sec_chan(bss, &bss_pri_chan, &bss_sec_chan);
323                 if (pri_chan == bss_pri_chan &&
324                     sec_chan == bss_sec_chan) {
325                         match = 1;
326                         break;
327                 }
328         }
329         if (!match) {
330                 for (i = 0; i < scan_res->num; i++) {
331                         struct wpa_scan_res *bss = scan_res->res[i];
332                         ieee80211n_get_pri_sec_chan(bss, &bss_pri_chan,
333                                                     &bss_sec_chan);
334                         if (pri_chan == bss_sec_chan &&
335                             sec_chan == bss_pri_chan) {
336                                 wpa_printf(MSG_INFO, "Switch own primary and "
337                                            "secondary channel due to BSS "
338                                            "overlap with " MACSTR,
339                                            MAC2STR(bss->bssid));
340                                 ieee80211n_switch_pri_sec(iface);
341                                 break;
342                         }
343                 }
344         }
345
346         return 1;
347 }
348
349
350 static int ieee80211n_check_40mhz_2g4(struct hostapd_iface *iface,
351                                       struct wpa_scan_results *scan_res)
352 {
353         int pri_freq, sec_freq;
354         int affected_start, affected_end;
355         size_t i;
356
357         pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);
358         if (iface->conf->secondary_channel > 0)
359                 sec_freq = pri_freq + 20;
360         else
361                 sec_freq = pri_freq - 20;
362         affected_start = (pri_freq + sec_freq) / 2 - 25;
363         affected_end = (pri_freq + sec_freq) / 2 + 25;
364         wpa_printf(MSG_DEBUG, "40 MHz affected channel range: [%d,%d] MHz",
365                    affected_start, affected_end);
366         for (i = 0; i < scan_res->num; i++) {
367                 struct wpa_scan_res *bss = scan_res->res[i];
368                 int pri = bss->freq;
369                 int sec = pri;
370                 int sec_chan, pri_chan;
371
372                 ieee80211n_get_pri_sec_chan(bss, &pri_chan, &sec_chan);
373
374                 if (sec_chan) {
375                         if (sec_chan < pri_chan)
376                                 sec = pri - 20;
377                         else
378                                 sec = pri + 20;
379                 }
380
381                 if ((pri < affected_start || pri > affected_end) &&
382                     (sec < affected_start || sec > affected_end))
383                         continue; /* not within affected channel range */
384
385                 wpa_printf(MSG_DEBUG, "Neighboring BSS: " MACSTR
386                            " freq=%d pri=%d sec=%d",
387                            MAC2STR(bss->bssid), bss->freq, pri_chan, sec_chan);
388
389                 if (sec_chan) {
390                         if (pri_freq != pri || sec_freq != sec) {
391                                 wpa_printf(MSG_DEBUG, "40 MHz pri/sec "
392                                            "mismatch with BSS " MACSTR
393                                            " <%d,%d> (chan=%d%c) vs. <%d,%d>",
394                                            MAC2STR(bss->bssid),
395                                            pri, sec, pri_chan,
396                                            sec > pri ? '+' : '-',
397                                            pri_freq, sec_freq);
398                                 return 0;
399                         }
400                 }
401
402                 /* TODO: 40 MHz intolerant */
403         }
404
405         return 1;
406 }
407
408
409 static void wpa_scan_results_free(struct wpa_scan_results *res)
410 {
411         size_t i;
412
413         if (res == NULL)
414                 return;
415
416         for (i = 0; i < res->num; i++)
417                 os_free(res->res[i]);
418         os_free(res->res);
419         os_free(res);
420 }
421
422
423 static void ieee80211n_check_scan(struct hostapd_iface *iface)
424 {
425         struct wpa_scan_results *scan_res;
426         int oper40;
427
428         /* Check list of neighboring BSSes (from scan) to see whether 40 MHz is
429          * allowed per IEEE 802.11n/D7.0, 11.14.3.2 */
430
431         iface->scan_cb = NULL;
432
433         scan_res = hostapd_driver_get_scan_results(iface->bss[0]);
434         if (scan_res == NULL) {
435                 hostapd_setup_interface_complete(iface, 1);
436                 return;
437         }
438
439         if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211A)
440                 oper40 = ieee80211n_check_40mhz_5g(iface, scan_res);
441         else
442                 oper40 = ieee80211n_check_40mhz_2g4(iface, scan_res);
443         wpa_scan_results_free(scan_res);
444
445         if (!oper40) {
446                 wpa_printf(MSG_INFO, "20/40 MHz operation not permitted on "
447                            "channel pri=%d sec=%d based on overlapping BSSes",
448                            iface->conf->channel,
449                            iface->conf->channel +
450                            iface->conf->secondary_channel * 4);
451                 iface->conf->secondary_channel = 0;
452                 iface->conf->ht_capab &= ~HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET;
453         }
454
455         hostapd_setup_interface_complete(iface, 0);
456 }
457
458
459 static int ieee80211n_check_40mhz(struct hostapd_iface *iface)
460 {
461         struct wpa_driver_scan_params params;
462
463         if (!iface->conf->secondary_channel)
464                 return 0; /* HT40 not used */
465
466         wpa_printf(MSG_DEBUG, "Scan for neighboring BSSes prior to enabling "
467                    "40 MHz channel");
468         os_memset(&params, 0, sizeof(params));
469         /* TODO: scan only the needed frequency */
470         if (hostapd_driver_scan(iface->bss[0], &params) < 0) {
471                 wpa_printf(MSG_ERROR, "Failed to request a scan of "
472                            "neighboring BSSes");
473                 return -1;
474         }
475
476         iface->scan_cb = ieee80211n_check_scan;
477         return 1;
478 }
479
480
481 static int ieee80211n_supported_ht_capab(struct hostapd_iface *iface)
482 {
483         u16 hw = iface->current_mode->ht_capab;
484         u16 conf = iface->conf->ht_capab;
485
486         if (!iface->conf->ieee80211n)
487                 return 1;
488
489         if ((conf & HT_CAP_INFO_LDPC_CODING_CAP) &&
490             !(hw & HT_CAP_INFO_LDPC_CODING_CAP)) {
491                 wpa_printf(MSG_ERROR, "Driver does not support configured "
492                            "HT capability [LDPC]");
493                 return 0;
494         }
495
496         if ((conf & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&
497             !(hw & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) {
498                 wpa_printf(MSG_ERROR, "Driver does not support configured "
499                            "HT capability [HT40*]");
500                 return 0;
501         }
502
503         if ((conf & HT_CAP_INFO_SMPS_MASK) != (hw & HT_CAP_INFO_SMPS_MASK) &&
504             (conf & HT_CAP_INFO_SMPS_MASK) != HT_CAP_INFO_SMPS_DISABLED) {
505                 wpa_printf(MSG_ERROR, "Driver does not support configured "
506                            "HT capability [SMPS-*]");
507                 return 0;
508         }
509
510         if ((conf & HT_CAP_INFO_GREEN_FIELD) &&
511             !(hw & HT_CAP_INFO_GREEN_FIELD)) {
512                 wpa_printf(MSG_ERROR, "Driver does not support configured "
513                            "HT capability [GF]");
514                 return 0;
515         }
516
517         if ((conf & HT_CAP_INFO_SHORT_GI20MHZ) &&
518             !(hw & HT_CAP_INFO_SHORT_GI20MHZ)) {
519                 wpa_printf(MSG_ERROR, "Driver does not support configured "
520                            "HT capability [SHORT-GI-20]");
521                 return 0;
522         }
523
524         if ((conf & HT_CAP_INFO_SHORT_GI40MHZ) &&
525             !(hw & HT_CAP_INFO_SHORT_GI40MHZ)) {
526                 wpa_printf(MSG_ERROR, "Driver does not support configured "
527                            "HT capability [SHORT-GI-40]");
528                 return 0;
529         }
530
531         if ((conf & HT_CAP_INFO_TX_STBC) && !(hw & HT_CAP_INFO_TX_STBC)) {
532                 wpa_printf(MSG_ERROR, "Driver does not support configured "
533                            "HT capability [TX-STBC]");
534                 return 0;
535         }
536
537         if ((conf & HT_CAP_INFO_RX_STBC_MASK) >
538             (hw & HT_CAP_INFO_RX_STBC_MASK)) {
539                 wpa_printf(MSG_ERROR, "Driver does not support configured "
540                            "HT capability [RX-STBC*]");
541                 return 0;
542         }
543
544         if ((conf & HT_CAP_INFO_DELAYED_BA) &&
545             !(hw & HT_CAP_INFO_DELAYED_BA)) {
546                 wpa_printf(MSG_ERROR, "Driver does not support configured "
547                            "HT capability [DELAYED-BA]");
548                 return 0;
549         }
550
551         if ((conf & HT_CAP_INFO_MAX_AMSDU_SIZE) &&
552             !(hw & HT_CAP_INFO_MAX_AMSDU_SIZE)) {
553                 wpa_printf(MSG_ERROR, "Driver does not support configured "
554                            "HT capability [MAX-AMSDU-7935]");
555                 return 0;
556         }
557
558         if ((conf & HT_CAP_INFO_DSSS_CCK40MHZ) &&
559             !(hw & HT_CAP_INFO_DSSS_CCK40MHZ)) {
560                 wpa_printf(MSG_ERROR, "Driver does not support configured "
561                            "HT capability [DSSS_CCK-40]");
562                 return 0;
563         }
564
565         if ((conf & HT_CAP_INFO_PSMP_SUPP) && !(hw & HT_CAP_INFO_PSMP_SUPP)) {
566                 wpa_printf(MSG_ERROR, "Driver does not support configured "
567                            "HT capability [PSMP]");
568                 return 0;
569         }
570
571         if ((conf & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT) &&
572             !(hw & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT)) {
573                 wpa_printf(MSG_ERROR, "Driver does not support configured "
574                            "HT capability [LSIG-TXOP-PROT]");
575                 return 0;
576         }
577
578         return 1;
579 }
580
581 #endif /* CONFIG_IEEE80211N */
582
583
584 int hostapd_check_ht_capab(struct hostapd_iface *iface)
585 {
586 #ifdef CONFIG_IEEE80211N
587         int ret;
588         ret = ieee80211n_check_40mhz(iface);
589         if (ret)
590                 return ret;
591         if (!ieee80211n_allowed_ht40_channel_pair(iface))
592                 return -1;
593         if (!ieee80211n_supported_ht_capab(iface))
594                 return -1;
595 #endif /* CONFIG_IEEE80211N */
596
597         return 0;
598 }
599
600
601 /**
602  * hostapd_select_hw_mode - Select the hardware mode
603  * @iface: Pointer to interface data.
604  * Returns: 0 on success, -1 on failure
605  *
606  * Sets up the hardware mode, channel, rates, and passive scanning
607  * based on the configuration.
608  */
609 int hostapd_select_hw_mode(struct hostapd_iface *iface)
610 {
611         int i, j, ok;
612
613         if (iface->num_hw_features < 1)
614                 return -1;
615
616         iface->current_mode = NULL;
617         for (i = 0; i < iface->num_hw_features; i++) {
618                 struct hostapd_hw_modes *mode = &iface->hw_features[i];
619                 if (mode->mode == iface->conf->hw_mode) {
620                         iface->current_mode = mode;
621                         break;
622                 }
623         }
624
625         if (iface->current_mode == NULL) {
626                 wpa_printf(MSG_ERROR, "Hardware does not support configured "
627                            "mode");
628                 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
629                                HOSTAPD_LEVEL_WARNING,
630                                "Hardware does not support configured mode "
631                                "(%d)", (int) iface->conf->hw_mode);
632                 return -1;
633         }
634
635         ok = 0;
636         for (j = 0; j < iface->current_mode->num_channels; j++) {
637                 struct hostapd_channel_data *chan =
638                         &iface->current_mode->channels[j];
639                 if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
640                     (chan->chan == iface->conf->channel)) {
641                         ok = 1;
642                         break;
643                 }
644         }
645         if (iface->conf->channel == 0) {
646                 /* TODO: could request a scan of neighboring BSSes and select
647                  * the channel automatically */
648                 wpa_printf(MSG_ERROR, "Channel not configured "
649                            "(hw_mode/channel in hostapd.conf)");
650                 return -1;
651         }
652         if (ok == 0 && iface->conf->channel != 0) {
653                 hostapd_logger(iface->bss[0], NULL,
654                                HOSTAPD_MODULE_IEEE80211,
655                                HOSTAPD_LEVEL_WARNING,
656                                "Configured channel (%d) not found from the "
657                                "channel list of current mode (%d) %s",
658                                iface->conf->channel,
659                                iface->current_mode->mode,
660                                hostapd_hw_mode_txt(iface->current_mode->mode));
661                 iface->current_mode = NULL;
662         }
663
664         if (iface->current_mode == NULL) {
665                 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
666                                HOSTAPD_LEVEL_WARNING,
667                                "Hardware does not support configured channel");
668                 return -1;
669         }
670
671         if (hostapd_prepare_rates(iface->bss[0], iface->current_mode)) {
672                 wpa_printf(MSG_ERROR, "Failed to prepare rates table.");
673                 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
674                                            HOSTAPD_LEVEL_WARNING,
675                                            "Failed to prepare rates table.");
676                 return -1;
677         }
678
679         return 0;
680 }
681
682
683 const char * hostapd_hw_mode_txt(int mode)
684 {
685         switch (mode) {
686         case HOSTAPD_MODE_IEEE80211A:
687                 return "IEEE 802.11a";
688         case HOSTAPD_MODE_IEEE80211B:
689                 return "IEEE 802.11b";
690         case HOSTAPD_MODE_IEEE80211G:
691                 return "IEEE 802.11g";
692         default:
693                 return "UNKNOWN";
694         }
695 }
696
697
698 int hostapd_hw_get_freq(struct hostapd_data *hapd, int chan)
699 {
700         int i;
701
702         if (!hapd->iface->current_mode)
703                 return 0;
704
705         for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
706                 struct hostapd_channel_data *ch =
707                         &hapd->iface->current_mode->channels[i];
708                 if (ch->chan == chan)
709                         return ch->freq;
710         }
711
712         return 0;
713 }
714
715
716 int hostapd_hw_get_channel(struct hostapd_data *hapd, int freq)
717 {
718         int i;
719
720         if (!hapd->iface->current_mode)
721                 return 0;
722
723         for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
724                 struct hostapd_channel_data *ch =
725                         &hapd->iface->current_mode->channels[i];
726                 if (ch->freq == freq)
727                         return ch->chan;
728         }
729
730         return 0;
731 }