wpa_supplicant: hw_features.c Source File

00001 /*
00002  * hostapd / Hardware feature query and different modes
00003  * Copyright 2002-2003, Instant802 Networks, Inc.
00004  * Copyright 2005-2006, Devicescape Software, Inc.
00005  * Copyright (c) 2008-2009, Jouni Malinen <j@w1.fi>
00006  *
00007  * This program is free software; you can redistribute it and/or modify
00008  * it under the terms of the GNU General Public License version 2 as
00009  * published by the Free Software Foundation.
00010  *
00011  * Alternatively, this software may be distributed under the terms of BSD
00012  * license.
00013  *
00014  * See README and COPYING for more details.
00015  */
00016 
00017 #include "utils/includes.h"
00018 
00019 #include "utils/common.h"
00020 #include "utils/eloop.h"
00021 #include "common/ieee802_11_defs.h"
00022 #include "common/ieee802_11_common.h"
00023 #include "drivers/driver.h"
00024 #include "hostapd.h"
00025 #include "ap_config.h"
00026 #include "ap_drv_ops.h"
00027 #include "hw_features.h"
00028 
00029 
00030 void hostapd_free_hw_features(struct hostapd_hw_modes *hw_features,
00031                               size_t num_hw_features)
00032 {
00033         size_t i;
00034 
00035         if (hw_features == NULL)
00036                 return;
00037 
00038         for (i = 0; i < num_hw_features; i++) {
00039                 os_free(hw_features[i].channels);
00040                 os_free(hw_features[i].rates);
00041         }
00042 
00043         os_free(hw_features);
00044 }
00045 
00046 
00047 int hostapd_get_hw_features(struct hostapd_iface *iface)
00048 {
00049         struct hostapd_data *hapd = iface->bss[0];
00050         int ret = 0, i, j;
00051         u16 num_modes, flags;
00052         struct hostapd_hw_modes *modes;
00053 
00054         if (hostapd_drv_none(hapd))
00055                 return -1;
00056         modes = hostapd_get_hw_feature_data(hapd, &num_modes, &flags);
00057         if (modes == NULL) {
00058                 hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
00059                                HOSTAPD_LEVEL_DEBUG,
00060                                "Fetching hardware channel/rate support not "
00061                                "supported.");
00062                 return -1;
00063         }
00064 
00065         iface->hw_flags = flags;
00066 
00067         hostapd_free_hw_features(iface->hw_features, iface->num_hw_features);
00068         iface->hw_features = modes;
00069         iface->num_hw_features = num_modes;
00070 
00071         for (i = 0; i < num_modes; i++) {
00072                 struct hostapd_hw_modes *feature = &modes[i];
00073                 /* set flag for channels we can use in current regulatory
00074                  * domain */
00075                 for (j = 0; j < feature->num_channels; j++) {
00076                         /*
00077                          * Disable all channels that are marked not to allow
00078                          * IBSS operation or active scanning. In addition,
00079                          * disable all channels that require radar detection,
00080                          * since that (in addition to full DFS) is not yet
00081                          * supported.
00082                          */
00083                         if (feature->channels[j].flag &
00084                             (HOSTAPD_CHAN_NO_IBSS |
00085                              HOSTAPD_CHAN_PASSIVE_SCAN |
00086                              HOSTAPD_CHAN_RADAR))
00087                                 feature->channels[j].flag |=
00088                                         HOSTAPD_CHAN_DISABLED;
00089                         if (feature->channels[j].flag & HOSTAPD_CHAN_DISABLED)
00090                                 continue;
00091                         wpa_printf(MSG_MSGDUMP, "Allowed channel: mode=%d "
00092                                    "chan=%d freq=%d MHz max_tx_power=%d dBm",
00093                                    feature->mode,
00094                                    feature->channels[j].chan,
00095                                    feature->channels[j].freq,
00096                                    feature->channels[j].max_tx_power);
00097                 }
00098         }
00099 
00100         return ret;
00101 }
00102 
00103 
00104 static int hostapd_prepare_rates(struct hostapd_data *hapd,
00105                                  struct hostapd_hw_modes *mode)
00106 {
00107         int i, num_basic_rates = 0;
00108         int basic_rates_a[] = { 60, 120, 240, -1 };
00109         int basic_rates_b[] = { 10, 20, -1 };
00110         int basic_rates_g[] = { 10, 20, 55, 110, -1 };
00111         int *basic_rates;
00112 
00113         if (hapd->iconf->basic_rates)
00114                 basic_rates = hapd->iconf->basic_rates;
00115         else switch (mode->mode) {
00116         case HOSTAPD_MODE_IEEE80211A:
00117                 basic_rates = basic_rates_a;
00118                 break;
00119         case HOSTAPD_MODE_IEEE80211B:
00120                 basic_rates = basic_rates_b;
00121                 break;
00122         case HOSTAPD_MODE_IEEE80211G:
00123                 basic_rates = basic_rates_g;
00124                 break;
00125         default:
00126                 return -1;
00127         }
00128 
00129         if (hostapd_set_rate_sets(hapd, hapd->iconf->supported_rates,
00130                                   basic_rates, mode->mode)) {
00131                 wpa_printf(MSG_ERROR, "Failed to update rate sets in kernel "
00132                            "module");
00133         }
00134 
00135         os_free(hapd->iface->current_rates);
00136         hapd->iface->num_rates = 0;
00137 
00138         hapd->iface->current_rates =
00139                 os_zalloc(mode->num_rates * sizeof(struct hostapd_rate_data));
00140         if (!hapd->iface->current_rates) {
00141                 wpa_printf(MSG_ERROR, "Failed to allocate memory for rate "
00142                            "table.");
00143                 return -1;
00144         }
00145 
00146         for (i = 0; i < mode->num_rates; i++) {
00147                 struct hostapd_rate_data *rate;
00148 
00149                 if (hapd->iconf->supported_rates &&
00150                     !hostapd_rate_found(hapd->iconf->supported_rates,
00151                                         mode->rates[i]))
00152                         continue;
00153 
00154                 rate = &hapd->iface->current_rates[hapd->iface->num_rates];
00155                 rate->rate = mode->rates[i];
00156                 if (hostapd_rate_found(basic_rates, rate->rate)) {
00157                         rate->flags |= HOSTAPD_RATE_BASIC;
00158                         num_basic_rates++;
00159                 }
00160                 wpa_printf(MSG_DEBUG, "RATE[%d] rate=%d flags=0x%x",
00161                            hapd->iface->num_rates, rate->rate, rate->flags);
00162                 hapd->iface->num_rates++;
00163         }
00164 
00165         if (hapd->iface->num_rates == 0 || num_basic_rates == 0) {
00166                 wpa_printf(MSG_ERROR, "No rates remaining in supported/basic "
00167                            "rate sets (%d,%d).",
00168                            hapd->iface->num_rates, num_basic_rates);
00169                 return -1;
00170         }
00171 
00172         return 0;
00173 }
00174 
00175 
00176 #ifdef CONFIG_IEEE80211N
00177 static int ieee80211n_allowed_ht40_channel_pair(struct hostapd_iface *iface)
00178 {
00179         int sec_chan, ok, j, first;
00180         int allowed[] = { 36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157,
00181                           184, 192 };
00182         size_t k;
00183 
00184         if (!iface->conf->secondary_channel)
00185                 return 1; /* HT40 not used */
00186 
00187         sec_chan = iface->conf->channel + iface->conf->secondary_channel * 4;
00188         wpa_printf(MSG_DEBUG, "HT40: control channel: %d  "
00189                    "secondary channel: %d",
00190                    iface->conf->channel, sec_chan);
00191 
00192         /* Verify that HT40 secondary channel is an allowed 20 MHz
00193          * channel */
00194         ok = 0;
00195         for (j = 0; j < iface->current_mode->num_channels; j++) {
00196                 struct hostapd_channel_data *chan =
00197                         &iface->current_mode->channels[j];
00198                 if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
00199                     chan->chan == sec_chan) {
00200                         ok = 1;
00201                         break;
00202                 }
00203         }
00204         if (!ok) {
00205                 wpa_printf(MSG_ERROR, "HT40 secondary channel %d not allowed",
00206                            sec_chan);
00207                 return 0;
00208         }
00209 
00210         /*
00211          * Verify that HT40 primary,secondary channel pair is allowed per
00212          * IEEE 802.11n Annex J. This is only needed for 5 GHz band since
00213          * 2.4 GHz rules allow all cases where the secondary channel fits into
00214          * the list of allowed channels (already checked above).
00215          */
00216         if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A)
00217                 return 1;
00218 
00219         if (iface->conf->secondary_channel > 0)
00220                 first = iface->conf->channel;
00221         else
00222                 first = sec_chan;
00223 
00224         ok = 0;
00225         for (k = 0; k < sizeof(allowed) / sizeof(allowed[0]); k++) {
00226                 if (first == allowed[k]) {
00227                         ok = 1;
00228                         break;
00229                 }
00230         }
00231         if (!ok) {
00232                 wpa_printf(MSG_ERROR, "HT40 channel pair (%d, %d) not allowed",
00233                            iface->conf->channel,
00234                            iface->conf->secondary_channel);
00235                 return 0;
00236         }
00237 
00238         return 1;
00239 }
00240 
00241 
00242 static void ieee80211n_switch_pri_sec(struct hostapd_iface *iface)
00243 {
00244         if (iface->conf->secondary_channel > 0) {
00245                 iface->conf->channel += 4;
00246                 iface->conf->secondary_channel = -1;
00247         } else {
00248                 iface->conf->channel -= 4;
00249                 iface->conf->secondary_channel = 1;
00250         }
00251 }
00252 
00253 
00254 static void ieee80211n_get_pri_sec_chan(struct wpa_scan_res *bss,
00255                                         int *pri_chan, int *sec_chan)
00256 {
00257         struct ieee80211_ht_operation *oper;
00258         struct ieee802_11_elems elems;
00259 
00260         *pri_chan = *sec_chan = 0;
00261 
00262         ieee802_11_parse_elems((u8 *) (bss + 1), bss->ie_len, &elems, 0);
00263         if (elems.ht_operation &&
00264             elems.ht_operation_len >= sizeof(*oper)) {
00265                 oper = (struct ieee80211_ht_operation *) elems.ht_operation;
00266                 *pri_chan = oper->control_chan;
00267                 if (oper->ht_param & HT_INFO_HT_PARAM_REC_TRANS_CHNL_WIDTH) {
00268                         if (oper->ht_param &
00269                             HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE)
00270                                 *sec_chan = *pri_chan + 4;
00271                         else if (oper->ht_param &
00272                                  HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW)
00273                                 *sec_chan = *pri_chan - 4;
00274                 }
00275         }
00276 }
00277 
00278 
00279 static int ieee80211n_check_40mhz_5g(struct hostapd_iface *iface,
00280                                      struct wpa_scan_results *scan_res)
00281 {
00282         int pri_chan, sec_chan, pri_freq, sec_freq, pri_bss, sec_bss;
00283         int bss_pri_chan, bss_sec_chan;
00284         size_t i;
00285         int match;
00286 
00287         pri_chan = iface->conf->channel;
00288         sec_chan = iface->conf->secondary_channel * 4;
00289         pri_freq = hostapd_hw_get_freq(iface->bss[0], pri_chan);
00290         if (iface->conf->secondary_channel > 0)
00291                 sec_freq = pri_freq + 20;
00292         else
00293                 sec_freq = pri_freq - 20;
00294 
00295         /*
00296          * Switch PRI/SEC channels if Beacons were detected on selected SEC
00297          * channel, but not on selected PRI channel.
00298          */
00299         pri_bss = sec_bss = 0;
00300         for (i = 0; i < scan_res->num; i++) {
00301                 struct wpa_scan_res *bss = scan_res->res[i];
00302                 if (bss->freq == pri_freq)
00303                         pri_bss++;
00304                 else if (bss->freq == sec_freq)
00305                         sec_bss++;
00306         }
00307         if (sec_bss && !pri_bss) {
00308                 wpa_printf(MSG_INFO, "Switch own primary and secondary "
00309                            "channel to get secondary channel with no Beacons "
00310                            "from other BSSes");
00311                 ieee80211n_switch_pri_sec(iface);
00312         }
00313 
00314         /*
00315          * Match PRI/SEC channel with any existing HT40 BSS on the same
00316          * channels that we are about to use (if already mixed order in
00317          * existing BSSes, use own preference).
00318          */
00319         match = 0;
00320         for (i = 0; i < scan_res->num; i++) {
00321                 struct wpa_scan_res *bss = scan_res->res[i];
00322                 ieee80211n_get_pri_sec_chan(bss, &bss_pri_chan, &bss_sec_chan);
00323                 if (pri_chan == bss_pri_chan &&
00324                     sec_chan == bss_sec_chan) {
00325                         match = 1;
00326                         break;
00327                 }
00328         }
00329         if (!match) {
00330                 for (i = 0; i < scan_res->num; i++) {
00331                         struct wpa_scan_res *bss = scan_res->res[i];
00332                         ieee80211n_get_pri_sec_chan(bss, &bss_pri_chan,
00333                                                     &bss_sec_chan);
00334                         if (pri_chan == bss_sec_chan &&
00335                             sec_chan == bss_pri_chan) {
00336                                 wpa_printf(MSG_INFO, "Switch own primary and "
00337                                            "secondary channel due to BSS "
00338                                            "overlap with " MACSTR,
00339                                            MAC2STR(bss->bssid));
00340                                 ieee80211n_switch_pri_sec(iface);
00341                                 break;
00342                         }
00343                 }
00344         }
00345 
00346         return 1;
00347 }
00348 
00349 
00350 static int ieee80211n_check_40mhz_2g4(struct hostapd_iface *iface,
00351                                       struct wpa_scan_results *scan_res)
00352 {
00353         int pri_freq, sec_freq;
00354         int affected_start, affected_end;
00355         size_t i;
00356 
00357         pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);
00358         if (iface->conf->secondary_channel > 0)
00359                 sec_freq = pri_freq + 20;
00360         else
00361                 sec_freq = pri_freq - 20;
00362         affected_start = (pri_freq + sec_freq) / 2 - 25;
00363         affected_end = (pri_freq + sec_freq) / 2 + 25;
00364         wpa_printf(MSG_DEBUG, "40 MHz affected channel range: [%d,%d] MHz",
00365                    affected_start, affected_end);
00366         for (i = 0; i < scan_res->num; i++) {
00367                 struct wpa_scan_res *bss = scan_res->res[i];
00368                 int pri = bss->freq;
00369                 int sec = pri;
00370                 int sec_chan, pri_chan;
00371 
00372                 ieee80211n_get_pri_sec_chan(bss, &pri_chan, &sec_chan);
00373 
00374                 if (sec_chan) {
00375                         if (sec_chan < pri_chan)
00376                                 sec = pri - 20;
00377                         else
00378                                 sec = pri + 20;
00379                 }
00380 
00381                 if ((pri < affected_start || pri > affected_end) &&
00382                     (sec < affected_start || sec > affected_end))
00383                         continue; /* not within affected channel range */
00384 
00385                 wpa_printf(MSG_DEBUG, "Neighboring BSS: " MACSTR
00386                            " freq=%d pri=%d sec=%d",
00387                            MAC2STR(bss->bssid), bss->freq, pri_chan, sec_chan);
00388 
00389                 if (sec_chan) {
00390                         if (pri_freq != pri || sec_freq != sec) {
00391                                 wpa_printf(MSG_DEBUG, "40 MHz pri/sec "
00392                                            "mismatch with BSS " MACSTR
00393                                            " <%d,%d> (chan=%d%c) vs. <%d,%d>",
00394                                            MAC2STR(bss->bssid),
00395                                            pri, sec, pri_chan,
00396                                            sec > pri ? '+' : '-',
00397                                            pri_freq, sec_freq);
00398                                 return 0;
00399                         }
00400                 }
00401 
00402                 /* TODO: 40 MHz intolerant */
00403         }
00404 
00405         return 1;
00406 }
00407 
00408 
00409 static void wpa_scan_results_free(struct wpa_scan_results *res)
00410 {
00411         size_t i;
00412 
00413         if (res == NULL)
00414                 return;
00415 
00416         for (i = 0; i < res->num; i++)
00417                 os_free(res->res[i]);
00418         os_free(res->res);
00419         os_free(res);
00420 }
00421 
00422 
00423 static void ieee80211n_check_scan(struct hostapd_iface *iface)
00424 {
00425         struct wpa_scan_results *scan_res;
00426         int oper40;
00427 
00428         /* Check list of neighboring BSSes (from scan) to see whether 40 MHz is
00429          * allowed per IEEE 802.11n/D7.0, 11.14.3.2 */
00430 
00431         iface->scan_cb = NULL;
00432 
00433         scan_res = hostapd_driver_get_scan_results(iface->bss[0]);
00434         if (scan_res == NULL) {
00435                 hostapd_setup_interface_complete(iface, 1);
00436                 return;
00437         }
00438 
00439         if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211A)
00440                 oper40 = ieee80211n_check_40mhz_5g(iface, scan_res);
00441         else
00442                 oper40 = ieee80211n_check_40mhz_2g4(iface, scan_res);
00443         wpa_scan_results_free(scan_res);
00444 
00445         if (!oper40) {
00446                 wpa_printf(MSG_INFO, "20/40 MHz operation not permitted on "
00447                            "channel pri=%d sec=%d based on overlapping BSSes",
00448                            iface->conf->channel,
00449                            iface->conf->channel +
00450                            iface->conf->secondary_channel * 4);
00451                 iface->conf->secondary_channel = 0;
00452                 iface->conf->ht_capab &= ~HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET;
00453         }
00454 
00455         hostapd_setup_interface_complete(iface, 0);
00456 }
00457 
00458 
00459 static int ieee80211n_check_40mhz(struct hostapd_iface *iface)
00460 {
00461         struct wpa_driver_scan_params params;
00462 
00463         if (!iface->conf->secondary_channel)
00464                 return 0; /* HT40 not used */
00465 
00466         wpa_printf(MSG_DEBUG, "Scan for neighboring BSSes prior to enabling "
00467                    "40 MHz channel");
00468         os_memset(&params, 0, sizeof(params));
00469         /* TODO: scan only the needed frequency */
00470         if (hostapd_driver_scan(iface->bss[0], &params) < 0) {
00471                 wpa_printf(MSG_ERROR, "Failed to request a scan of "
00472                            "neighboring BSSes");
00473                 return -1;
00474         }
00475 
00476         iface->scan_cb = ieee80211n_check_scan;
00477         return 1;
00478 }
00479 
00480 
00481 static int ieee80211n_supported_ht_capab(struct hostapd_iface *iface)
00482 {
00483         u16 hw = iface->current_mode->ht_capab;
00484         u16 conf = iface->conf->ht_capab;
00485 
00486         if (!iface->conf->ieee80211n)
00487                 return 1;
00488 
00489         if ((conf & HT_CAP_INFO_LDPC_CODING_CAP) &&
00490             !(hw & HT_CAP_INFO_LDPC_CODING_CAP)) {
00491                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00492                            "HT capability [LDPC]");
00493                 return 0;
00494         }
00495 
00496         if ((conf & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET) &&
00497             !(hw & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) {
00498                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00499                            "HT capability [HT40*]");
00500                 return 0;
00501         }
00502 
00503         if ((conf & HT_CAP_INFO_SMPS_MASK) != (hw & HT_CAP_INFO_SMPS_MASK) &&
00504             (conf & HT_CAP_INFO_SMPS_MASK) != HT_CAP_INFO_SMPS_DISABLED) {
00505                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00506                            "HT capability [SMPS-*]");
00507                 return 0;
00508         }
00509 
00510         if ((conf & HT_CAP_INFO_GREEN_FIELD) &&
00511             !(hw & HT_CAP_INFO_GREEN_FIELD)) {
00512                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00513                            "HT capability [GF]");
00514                 return 0;
00515         }
00516 
00517         if ((conf & HT_CAP_INFO_SHORT_GI20MHZ) &&
00518             !(hw & HT_CAP_INFO_SHORT_GI20MHZ)) {
00519                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00520                            "HT capability [SHORT-GI-20]");
00521                 return 0;
00522         }
00523 
00524         if ((conf & HT_CAP_INFO_SHORT_GI40MHZ) &&
00525             !(hw & HT_CAP_INFO_SHORT_GI40MHZ)) {
00526                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00527                            "HT capability [SHORT-GI-40]");
00528                 return 0;
00529         }
00530 
00531         if ((conf & HT_CAP_INFO_TX_STBC) && !(hw & HT_CAP_INFO_TX_STBC)) {
00532                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00533                            "HT capability [TX-STBC]");
00534                 return 0;
00535         }
00536 
00537         if ((conf & HT_CAP_INFO_RX_STBC_MASK) >
00538             (hw & HT_CAP_INFO_RX_STBC_MASK)) {
00539                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00540                            "HT capability [RX-STBC*]");
00541                 return 0;
00542         }
00543 
00544         if ((conf & HT_CAP_INFO_DELAYED_BA) &&
00545             !(hw & HT_CAP_INFO_DELAYED_BA)) {
00546                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00547                            "HT capability [DELAYED-BA]");
00548                 return 0;
00549         }
00550 
00551         if ((conf & HT_CAP_INFO_MAX_AMSDU_SIZE) &&
00552             !(hw & HT_CAP_INFO_MAX_AMSDU_SIZE)) {
00553                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00554                            "HT capability [MAX-AMSDU-7935]");
00555                 return 0;
00556         }
00557 
00558         if ((conf & HT_CAP_INFO_DSSS_CCK40MHZ) &&
00559             !(hw & HT_CAP_INFO_DSSS_CCK40MHZ)) {
00560                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00561                            "HT capability [DSSS_CCK-40]");
00562                 return 0;
00563         }
00564 
00565         if ((conf & HT_CAP_INFO_PSMP_SUPP) && !(hw & HT_CAP_INFO_PSMP_SUPP)) {
00566                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00567                            "HT capability [PSMP]");
00568                 return 0;
00569         }
00570 
00571         if ((conf & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT) &&
00572             !(hw & HT_CAP_INFO_LSIG_TXOP_PROTECT_SUPPORT)) {
00573                 wpa_printf(MSG_ERROR, "Driver does not support configured "
00574                            "HT capability [LSIG-TXOP-PROT]");
00575                 return 0;
00576         }
00577 
00578         return 1;
00579 }
00580 
00581 #endif /* CONFIG_IEEE80211N */
00582 
00583 
00584 int hostapd_check_ht_capab(struct hostapd_iface *iface)
00585 {
00586 #ifdef CONFIG_IEEE80211N
00587         int ret;
00588         ret = ieee80211n_check_40mhz(iface);
00589         if (ret)
00590                 return ret;
00591         if (!ieee80211n_allowed_ht40_channel_pair(iface))
00592                 return -1;
00593         if (!ieee80211n_supported_ht_capab(iface))
00594                 return -1;
00595 #endif /* CONFIG_IEEE80211N */
00596 
00597         return 0;
00598 }
00599 
00600 
00609 int hostapd_select_hw_mode(struct hostapd_iface *iface)
00610 {
00611         int i, j, ok;
00612 
00613         if (iface->num_hw_features < 1)
00614                 return -1;
00615 
00616         iface->current_mode = NULL;
00617         for (i = 0; i < iface->num_hw_features; i++) {
00618                 struct hostapd_hw_modes *mode = &iface->hw_features[i];
00619                 if (mode->mode == iface->conf->hw_mode) {
00620                         iface->current_mode = mode;
00621                         break;
00622                 }
00623         }
00624 
00625         if (iface->current_mode == NULL) {
00626                 wpa_printf(MSG_ERROR, "Hardware does not support configured "
00627                            "mode");
00628                 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
00629                                HOSTAPD_LEVEL_WARNING,
00630                                "Hardware does not support configured mode "
00631                                "(%d)", (int) iface->conf->hw_mode);
00632                 return -1;
00633         }
00634 
00635         ok = 0;
00636         for (j = 0; j < iface->current_mode->num_channels; j++) {
00637                 struct hostapd_channel_data *chan =
00638                         &iface->current_mode->channels[j];
00639                 if (!(chan->flag & HOSTAPD_CHAN_DISABLED) &&
00640                     (chan->chan == iface->conf->channel)) {
00641                         ok = 1;
00642                         break;
00643                 }
00644         }
00645         if (iface->conf->channel == 0) {
00646                 /* TODO: could request a scan of neighboring BSSes and select
00647                  * the channel automatically */
00648                 wpa_printf(MSG_ERROR, "Channel not configured "
00649                            "(hw_mode/channel in hostapd.conf)");
00650                 return -1;
00651         }
00652         if (ok == 0 && iface->conf->channel != 0) {
00653                 hostapd_logger(iface->bss[0], NULL,
00654                                HOSTAPD_MODULE_IEEE80211,
00655                                HOSTAPD_LEVEL_WARNING,
00656                                "Configured channel (%d) not found from the "
00657                                "channel list of current mode (%d) %s",
00658                                iface->conf->channel,
00659                                iface->current_mode->mode,
00660                                hostapd_hw_mode_txt(iface->current_mode->mode));
00661                 iface->current_mode = NULL;
00662         }
00663 
00664         if (iface->current_mode == NULL) {
00665                 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
00666                                HOSTAPD_LEVEL_WARNING,
00667                                "Hardware does not support configured channel");
00668                 return -1;
00669         }
00670 
00671         if (hostapd_prepare_rates(iface->bss[0], iface->current_mode)) {
00672                 wpa_printf(MSG_ERROR, "Failed to prepare rates table.");
00673                 hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
00674                                            HOSTAPD_LEVEL_WARNING,
00675                                            "Failed to prepare rates table.");
00676                 return -1;
00677         }
00678 
00679         return 0;
00680 }
00681 
00682 
00683 const char * hostapd_hw_mode_txt(int mode)
00684 {
00685         switch (mode) {
00686         case HOSTAPD_MODE_IEEE80211A:
00687                 return "IEEE 802.11a";
00688         case HOSTAPD_MODE_IEEE80211B:
00689                 return "IEEE 802.11b";
00690         case HOSTAPD_MODE_IEEE80211G:
00691                 return "IEEE 802.11g";
00692         default:
00693                 return "UNKNOWN";
00694         }
00695 }
00696 
00697 
00698 int hostapd_hw_get_freq(struct hostapd_data *hapd, int chan)
00699 {
00700         int i;
00701 
00702         if (!hapd->iface->current_mode)
00703                 return 0;
00704 
00705         for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
00706                 struct hostapd_channel_data *ch =
00707                         &hapd->iface->current_mode->channels[i];
00708                 if (ch->chan == chan)
00709                         return ch->freq;
00710         }
00711 
00712         return 0;
00713 }
00714 
00715 
00716 int hostapd_hw_get_channel(struct hostapd_data *hapd, int freq)
00717 {
00718         int i;
00719 
00720         if (!hapd->iface->current_mode)
00721                 return 0;
00722 
00723         for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
00724                 struct hostapd_channel_data *ch =
00725                         &hapd->iface->current_mode->channels[i];
00726                 if (ch->freq == freq)
00727                         return ch->chan;
00728         }
00729 
00730         return 0;
00731 }