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, Jouni Malinen <j@w1.fi>
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.
11 * Alternatively, this software may be distributed under the terms of BSD
14 * See README and COPYING for more details.
20 #include "ieee802_11_defs.h"
21 #include "ieee802_11_common.h"
23 #include "hw_features.h"
28 void hostapd_free_hw_features(struct hostapd_hw_modes *hw_features,
29 size_t num_hw_features)
33 if (hw_features == NULL)
36 for (i = 0; i < num_hw_features; i++) {
37 os_free(hw_features[i].channels);
38 os_free(hw_features[i].rates);
45 int hostapd_get_hw_features(struct hostapd_iface *iface)
47 struct hostapd_data *hapd = iface->bss[0];
50 struct hostapd_hw_modes *modes;
52 if (hostapd_drv_none(hapd))
54 modes = hostapd_get_hw_feature_data(hapd, &num_modes, &flags);
56 hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
58 "Fetching hardware channel/rate support not "
63 iface->hw_flags = flags;
65 hostapd_free_hw_features(iface->hw_features, iface->num_hw_features);
66 iface->hw_features = modes;
67 iface->num_hw_features = num_modes;
69 for (i = 0; i < num_modes; i++) {
70 struct hostapd_hw_modes *feature = &modes[i];
71 /* set flag for channels we can use in current regulatory
73 for (j = 0; j < feature->num_channels; j++) {
75 * Disable all channels that are marked not to allow
76 * IBSS operation or active scanning. In addition,
77 * disable all channels that require radar detection,
78 * since that (in addition to full DFS) is not yet
81 if (feature->channels[j].flag &
82 (HOSTAPD_CHAN_NO_IBSS |
83 HOSTAPD_CHAN_PASSIVE_SCAN |
85 feature->channels[j].flag |=
86 HOSTAPD_CHAN_DISABLED;
87 if (feature->channels[j].flag & HOSTAPD_CHAN_DISABLED)
89 wpa_printf(MSG_MSGDUMP, "Allowed channel: mode=%d "
90 "chan=%d freq=%d MHz max_tx_power=%d dBm",
92 feature->channels[j].chan,
93 feature->channels[j].freq,
94 feature->channels[j].max_tx_power);
102 static int hostapd_prepare_rates(struct hostapd_data *hapd,
103 struct hostapd_hw_modes *mode)
105 int i, num_basic_rates = 0;
106 int basic_rates_a[] = { 60, 120, 240, -1 };
107 int basic_rates_b[] = { 10, 20, -1 };
108 int basic_rates_g[] = { 10, 20, 55, 110, -1 };
111 if (hapd->iconf->basic_rates)
112 basic_rates = hapd->iconf->basic_rates;
113 else switch (mode->mode) {
114 case HOSTAPD_MODE_IEEE80211A:
115 basic_rates = basic_rates_a;
117 case HOSTAPD_MODE_IEEE80211B:
118 basic_rates = basic_rates_b;
120 case HOSTAPD_MODE_IEEE80211G:
121 basic_rates = basic_rates_g;
127 if (hostapd_set_rate_sets(hapd, hapd->iconf->supported_rates,
128 basic_rates, mode->mode)) {
129 wpa_printf(MSG_ERROR, "Failed to update rate sets in kernel "
133 os_free(hapd->iface->current_rates);
134 hapd->iface->num_rates = 0;
136 hapd->iface->current_rates =
137 os_malloc(mode->num_rates * sizeof(struct hostapd_rate_data));
138 if (!hapd->iface->current_rates) {
139 wpa_printf(MSG_ERROR, "Failed to allocate memory for rate "
144 for (i = 0; i < mode->num_rates; i++) {
145 struct hostapd_rate_data *rate;
147 if (hapd->iconf->supported_rates &&
148 !hostapd_rate_found(hapd->iconf->supported_rates,
149 mode->rates[i].rate))
152 rate = &hapd->iface->current_rates[hapd->iface->num_rates];
153 os_memcpy(rate, &mode->rates[i],
154 sizeof(struct hostapd_rate_data));
155 if (hostapd_rate_found(basic_rates, rate->rate)) {
156 rate->flags |= HOSTAPD_RATE_BASIC;
159 rate->flags &= ~HOSTAPD_RATE_BASIC;
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++;
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);
176 #ifdef CONFIG_IEEE80211N
177 static int ieee80211n_allowed_ht40_channel_pair(struct hostapd_iface *iface)
179 int sec_chan, ok, j, first;
180 int allowed[] = { 36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157,
184 if (!iface->conf->secondary_channel)
185 return 1; /* HT40 not used */
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);
192 /* Verify that HT40 secondary channel is an allowed 20 MHz
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) {
205 wpa_printf(MSG_ERROR, "HT40 secondary channel %d not allowed",
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).
216 if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A)
219 if (iface->conf->secondary_channel > 0)
220 first = iface->conf->channel;
225 for (k = 0; k < sizeof(allowed) / sizeof(allowed[0]); k++) {
226 if (first == allowed[k]) {
232 wpa_printf(MSG_ERROR, "HT40 channel pair (%d, %d) not allowed",
233 iface->conf->channel,
234 iface->conf->secondary_channel);
242 static void ieee80211n_switch_pri_sec(struct hostapd_iface *iface)
244 if (iface->conf->secondary_channel > 0) {
245 iface->conf->channel += 4;
246 iface->conf->secondary_channel = -1;
248 iface->conf->channel -= 4;
249 iface->conf->secondary_channel = 1;
254 static void ieee80211n_get_pri_sec_chan(struct wpa_scan_res *bss,
255 int *pri_chan, int *sec_chan)
257 struct ieee80211_ht_operation *oper;
258 struct ieee802_11_elems elems;
260 *pri_chan = *sec_chan = 0;
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) {
269 HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE)
270 *sec_chan = *pri_chan + 4;
271 else if (oper->ht_param &
272 HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW)
273 *sec_chan = *pri_chan - 4;
279 static int ieee80211n_check_40mhz_5g(struct hostapd_iface *iface,
280 struct wpa_scan_results *scan_res)
282 int pri_chan, sec_chan, pri_freq, sec_freq, pri_bss, sec_bss;
283 int bss_pri_chan, bss_sec_chan;
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;
293 sec_freq = pri_freq - 20;
296 * Switch PRI/SEC channels if Beacons were detected on selected SEC
297 * channel, but not on selected PRI channel.
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)
304 else if (bss->freq == sec_freq)
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 "
311 ieee80211n_switch_pri_sec(iface);
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).
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) {
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, &pri_chan, &sec_chan);
333 if (pri_chan == bss_sec_chan &&
334 sec_chan == bss_pri_chan) {
335 wpa_printf(MSG_INFO, "Switch own primary and "
336 "secondary channel due to BSS "
337 "overlap with " MACSTR,
338 MAC2STR(bss->bssid));
339 ieee80211n_switch_pri_sec(iface);
349 static int ieee80211n_check_40mhz_2g4(struct hostapd_iface *iface,
350 struct wpa_scan_results *scan_res)
352 int pri_freq, sec_freq;
353 int affected_start, affected_end;
356 pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);
357 if (iface->conf->secondary_channel > 0)
358 sec_freq = pri_freq + 20;
360 sec_freq = pri_freq - 20;
361 affected_start = (pri_freq + sec_freq) / 2 - 25;
362 affected_end = (pri_freq + sec_freq) / 2 + 25;
363 wpa_printf(MSG_DEBUG, "40 MHz affected channel range: [%d,%d] MHz",
364 affected_start, affected_end);
365 for (i = 0; i < scan_res->num; i++) {
366 struct wpa_scan_res *bss = scan_res->res[i];
369 int sec_chan, pri_chan;
371 ieee80211n_get_pri_sec_chan(bss, &pri_chan, &sec_chan);
374 if (sec_chan < pri_chan)
380 if ((pri < affected_start || pri > affected_end) &&
381 (sec < affected_start || sec > affected_end))
382 continue; /* not within affected channel range */
384 wpa_printf(MSG_DEBUG, "Neighboring BSS: " MACSTR
385 " freq=%d pri=%d sec=%d",
386 MAC2STR(bss->bssid), bss->freq, pri_chan, sec_chan);
389 if (pri_freq != pri || sec_freq != sec) {
390 wpa_printf(MSG_DEBUG, "40 MHz pri/sec "
391 "mismatch with BSS " MACSTR
392 " <%d,%d> (chan=%d%c) vs. <%d,%d>",
395 sec > pri ? '+' : '-',
401 /* TODO: 40 MHz intolerant */
408 static void ieee80211n_check_scan(struct hostapd_iface *iface)
410 struct wpa_scan_results *scan_res;
413 /* Check list of neighboring BSSes (from scan) to see whether 40 MHz is
414 * allowed per IEEE 802.11n/D7.0, 11.14.3.2 */
416 iface->scan_cb = NULL;
418 scan_res = hostapd_driver_get_scan_results(iface->bss[0]);
419 if (scan_res == NULL) {
420 hostapd_setup_interface_complete(iface, 1);
424 if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211A)
425 oper40 = ieee80211n_check_40mhz_5g(iface, scan_res);
427 oper40 = ieee80211n_check_40mhz_2g4(iface, scan_res);
428 wpa_scan_results_free(scan_res);
431 wpa_printf(MSG_INFO, "20/40 MHz operation not permitted on "
432 "channel pri=%d sec=%d based on overlapping BSSes",
433 iface->conf->channel,
434 iface->conf->channel +
435 iface->conf->secondary_channel * 4);
436 iface->conf->secondary_channel = 0;
437 iface->conf->ht_capab &= ~HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET;
440 hostapd_setup_interface_complete(iface, 0);
444 static int ieee80211n_check_40mhz(struct hostapd_iface *iface)
446 struct wpa_driver_scan_params params;
448 if (!iface->conf->secondary_channel)
449 return 0; /* HT40 not used */
451 wpa_printf(MSG_DEBUG, "Scan for neighboring BSSes prior to enabling "
453 os_memset(¶ms, 0, sizeof(params));
454 /* TODO: scan only the needed frequency */
455 if (hostapd_driver_scan(iface->bss[0], ¶ms) < 0) {
456 wpa_printf(MSG_ERROR, "Failed to request a scan of "
457 "neighboring BSSes");
461 iface->scan_cb = ieee80211n_check_scan;
466 static int ieee80211n_supported_ht_capab(struct hostapd_iface *iface)
468 u16 hw = iface->current_mode->ht_capab;
469 u16 conf = iface->conf->ht_capab;
471 if (!iface->conf->ieee80211n)
474 if ((conf & HT_CAP_INFO_LDPC_CODING_CAP) &&
475 !(hw & HT_CAP_INFO_LDPC_CODING_CAP)) {
476 wpa_printf(MSG_ERROR, "Driver does not support configured "
477 "HT capability [LDPC]");
481 if ((conf & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&
482 !(hw & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) {
483 wpa_printf(MSG_ERROR, "Driver does not support configured "
484 "HT capability [HT40*]");
488 if ((conf & HT_CAP_INFO_SMPS_MASK) != (hw & HT_CAP_INFO_SMPS_MASK) &&
489 (conf & HT_CAP_INFO_SMPS_MASK) != HT_CAP_INFO_SMPS_DISABLED) {
490 wpa_printf(MSG_ERROR, "Driver does not support configured "
491 "HT capability [SMPS-*]");
495 if ((conf & HT_CAP_INFO_GREEN_FIELD) &&
496 !(hw & HT_CAP_INFO_GREEN_FIELD)) {
497 wpa_printf(MSG_ERROR, "Driver does not support configured "
498 "HT capability [GF]");
502 if ((conf & HT_CAP_INFO_SHORT_GI20MHZ) &&
503 !(hw & HT_CAP_INFO_SHORT_GI20MHZ)) {
504 wpa_printf(MSG_ERROR, "Driver does not support configured "
505 "HT capability [SHORT-GI-20]");
509 if ((conf & HT_CAP_INFO_SHORT_GI40MHZ) &&
510 !(hw & HT_CAP_INFO_SHORT_GI40MHZ)) {
511 wpa_printf(MSG_ERROR, "Driver does not support configured "
512 "HT capability [SHORT-GI-40]");
516 if ((conf & HT_CAP_INFO_TX_STBC) && !(hw & HT_CAP_INFO_TX_STBC)) {
517 wpa_printf(MSG_ERROR, "Driver does not support configured "
518 "HT capability [TX-STBC]");
522 if ((conf & HT_CAP_INFO_RX_STBC_MASK) >
523 (hw & HT_CAP_INFO_RX_STBC_MASK)) {
524 wpa_printf(MSG_ERROR, "Driver does not support configured "
525 "HT capability [RX-STBC*]");
529 if ((conf & HT_CAP_INFO_DELAYED_BA) &&
530 !(hw & HT_CAP_INFO_DELAYED_BA)) {
531 wpa_printf(MSG_ERROR, "Driver does not support configured "
532 "HT capability [DELAYED-BA]");
536 if ((conf & HT_CAP_INFO_MAX_AMSDU_SIZE) &&
537 !(hw & HT_CAP_INFO_MAX_AMSDU_SIZE)) {
538 wpa_printf(MSG_ERROR, "Driver does not support configured "
539 "HT capability [MAX-AMSDU-7935]");
543 if ((conf & HT_CAP_INFO_DSSS_CCK40MHZ) &&
544 !(hw & HT_CAP_INFO_DSSS_CCK40MHZ)) {
545 wpa_printf(MSG_ERROR, "Driver does not support configured "
546 "HT capability [DSSS_CCK-40]");
550 if ((conf & HT_CAP_INFO_PSMP_SUPP) && !(hw & HT_CAP_INFO_PSMP_SUPP)) {
551 wpa_printf(MSG_ERROR, "Driver does not support configured "
552 "HT capability [PSMP]");
556 if ((conf & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT) &&
557 !(hw & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT)) {
558 wpa_printf(MSG_ERROR, "Driver does not support configured "
559 "HT capability [LSIG-TXOP-PROT]");
566 #endif /* CONFIG_IEEE80211N */
569 int hostapd_check_ht_capab(struct hostapd_iface *iface)
571 #ifdef CONFIG_IEEE80211N
573 ret = ieee80211n_check_40mhz(iface);
576 if (!ieee80211n_allowed_ht40_channel_pair(iface))
578 if (!ieee80211n_supported_ht_capab(iface))
580 #endif /* CONFIG_IEEE80211N */
587 * hostapd_select_hw_mode - Select the hardware mode
588 * @iface: Pointer to interface data.
589 * Returns: 0 on success, -1 on failure
591 * Sets up the hardware mode, channel, rates, and passive scanning
592 * based on the configuration.
594 int hostapd_select_hw_mode(struct hostapd_iface *iface)
598 if (iface->num_hw_features < 1)
601 iface->current_mode = NULL;
602 for (i = 0; i < iface->num_hw_features; i++) {
603 struct hostapd_hw_modes *mode = &iface->hw_features[i];
604 if (mode->mode == iface->conf->hw_mode) {
605 iface->current_mode = mode;
610 if (iface->current_mode == NULL) {
611 wpa_printf(MSG_ERROR, "Hardware does not support configured "
613 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
614 HOSTAPD_LEVEL_WARNING,
615 "Hardware does not support configured mode "
616 "(%d)", (int) iface->conf->hw_mode);
621 for (j = 0; j < iface->current_mode->num_channels; j++) {
622 struct hostapd_channel_data *chan =
623 &iface->current_mode->channels[j];
624 if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
625 (chan->chan == iface->conf->channel)) {
630 if (iface->conf->channel == 0) {
631 /* TODO: could request a scan of neighboring BSSes and select
632 * the channel automatically */
633 wpa_printf(MSG_ERROR, "Channel not configured "
634 "(hw_mode/channel in hostapd.conf)");
637 if (ok == 0 && iface->conf->channel != 0) {
638 hostapd_logger(iface->bss[0], NULL,
639 HOSTAPD_MODULE_IEEE80211,
640 HOSTAPD_LEVEL_WARNING,
641 "Configured channel (%d) not found from the "
642 "channel list of current mode (%d) %s",
643 iface->conf->channel,
644 iface->current_mode->mode,
645 hostapd_hw_mode_txt(iface->current_mode->mode));
646 iface->current_mode = NULL;
649 if (iface->current_mode == NULL) {
650 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
651 HOSTAPD_LEVEL_WARNING,
652 "Hardware does not support configured channel");
656 if (hostapd_prepare_rates(iface->bss[0], iface->current_mode)) {
657 wpa_printf(MSG_ERROR, "Failed to prepare rates table.");
658 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
659 HOSTAPD_LEVEL_WARNING,
660 "Failed to prepare rates table.");
668 const char * hostapd_hw_mode_txt(int mode)
671 case HOSTAPD_MODE_IEEE80211A:
672 return "IEEE 802.11a";
673 case HOSTAPD_MODE_IEEE80211B:
674 return "IEEE 802.11b";
675 case HOSTAPD_MODE_IEEE80211G:
676 return "IEEE 802.11g";
683 int hostapd_hw_get_freq(struct hostapd_data *hapd, int chan)
687 if (!hapd->iface->current_mode)
690 for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
691 struct hostapd_channel_data *ch =
692 &hapd->iface->current_mode->channels[i];
693 if (ch->chan == chan)
701 int hostapd_hw_get_channel(struct hostapd_data *hapd, int freq)
705 if (!hapd->iface->current_mode)
708 for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
709 struct hostapd_channel_data *ch =
710 &hapd->iface->current_mode->channels[i];
711 if (ch->freq == freq)