hw_features.c

Go to the documentation of this file.

#include "includes.h"

#include "hostapd.h"
#include "hw_features.h"
#include "driver.h"
#include "config.h"
#include "ieee802_11.h"
#include "eloop.h"


void hostapd_free_hw_features(struct hostapd_hw_modes *hw_features,
                              size_t num_hw_features)
{
        size_t i;

        if (hw_features == NULL)
                return;

        for (i = 0; i < num_hw_features; i++) {
                free(hw_features[i].channels);
                free(hw_features[i].rates);
        }

        free(hw_features);
}


int hostapd_get_hw_features(struct hostapd_iface *iface)
{
        struct hostapd_data *hapd = iface->bss[0];
        int ret = 0, i, j;
        u16 num_modes, flags;
        struct hostapd_hw_modes *modes;

        modes = hostapd_get_hw_feature_data(hapd, &num_modes, &flags);
        if (modes == NULL) {
                hostapd_logger(hapd, NULL, HOSTAPD_MODULE_IEEE80211,
                               HOSTAPD_LEVEL_DEBUG,
                               "Fetching hardware channel/rate support not "
                               "supported.");
                return -1;
        }

        iface->hw_flags = flags;

        hostapd_free_hw_features(iface->hw_features, iface->num_hw_features);
        iface->hw_features = modes;
        iface->num_hw_features = num_modes;

        for (i = 0; i < num_modes; i++) {
                struct hostapd_hw_modes *feature = &modes[i];
                /* set flag for channels we can use in current regulatory
                 * domain */
                for (j = 0; j < feature->num_channels; j++) {
                        /* TODO: add regulatory domain lookup */
                        unsigned char power_level = 0;
                        unsigned char antenna_max = 0;

                        if ((feature->mode == HOSTAPD_MODE_IEEE80211G ||
                             feature->mode == HOSTAPD_MODE_IEEE80211B) &&
                            feature->channels[j].chan >= 1 &&
                            feature->channels[j].chan <= 11) {
                                power_level = 20;
                                feature->channels[j].flag |=
                                        HOSTAPD_CHAN_W_SCAN;
                        } else
                                feature->channels[j].flag &=
                                        ~HOSTAPD_CHAN_W_SCAN;

                        hostapd_set_channel_flag(hapd, feature->mode,
                                                 feature->channels[j].chan,
                                                 feature->channels[j].flag,
                                                 power_level,
                                                 antenna_max);
                }
        }

        return ret;
}


static int hostapd_prepare_rates(struct hostapd_data *hapd,
                                 struct hostapd_hw_modes *mode)
{
        int i, num_basic_rates = 0;
        int basic_rates_a[] = { 60, 120, 240, -1 };
        int basic_rates_b[] = { 10, 20, -1 };
        int basic_rates_g[] = { 10, 20, 55, 110, -1 };
        int *basic_rates;

        if (hapd->iconf->basic_rates)
                basic_rates = hapd->iconf->basic_rates;
        else switch (mode->mode) {
        case HOSTAPD_MODE_IEEE80211A:
                basic_rates = basic_rates_a;
                break;
        case HOSTAPD_MODE_IEEE80211B:
                basic_rates = basic_rates_b;
                break;
        case HOSTAPD_MODE_IEEE80211G:
                basic_rates = basic_rates_g;
                break;
        default:
                return -1;
        }

        if (hostapd_set_rate_sets(hapd, hapd->iconf->supported_rates,
                                  basic_rates, mode->mode)) {
                printf("Failed to update rate sets in kernel module\n");
        }

        free(hapd->iface->current_rates);
        hapd->iface->num_rates = 0;

        hapd->iface->current_rates =
                malloc(mode->num_rates * sizeof(struct hostapd_rate_data));
        if (!hapd->iface->current_rates) {
                printf("Failed to allocate memory for rate table.\n");
                return -1;
        }

        for (i = 0; i < mode->num_rates; i++) {
                struct hostapd_rate_data *rate;

                if (hapd->iconf->supported_rates &&
                    !hostapd_rate_found(hapd->iconf->supported_rates,
                                        mode->rates[i].rate))
                        continue;

                rate = &hapd->iface->current_rates[hapd->iface->num_rates];
                memcpy(rate, &mode->rates[i],
                       sizeof(struct hostapd_rate_data));
                if (hostapd_rate_found(basic_rates, rate->rate)) {
                        rate->flags |= HOSTAPD_RATE_BASIC;
                        num_basic_rates++;
                } else
                        rate->flags &= ~HOSTAPD_RATE_BASIC;
                HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
                              "RATE[%d] rate=%d flags=0x%x\n",
                              hapd->iface->num_rates, rate->rate, rate->flags);
                hapd->iface->num_rates++;
        }

        if (hapd->iface->num_rates == 0 || num_basic_rates == 0) {
                printf("No rates remaining in supported/basic rate sets "
                       "(%d,%d).\n", hapd->iface->num_rates, num_basic_rates);
                return -1;
        }

        return 0;
}


static void select_hw_mode_start(void *eloop_data, void *user_ctx);
static void select_hw_mode2_handler(void *eloop_data, void *user_ctx);

static int select_hw_mode_finalize(struct hostapd_iface *iface, int status)
{
        hostapd_iface_cb cb;

        if (!iface->hw_mode_sel_cb)
                return -1;

        eloop_cancel_timeout(select_hw_mode_start, iface, NULL);
        eloop_cancel_timeout(select_hw_mode2_handler, iface, NULL);

        cb = iface->hw_mode_sel_cb;

        iface->hw_mode_sel_cb = NULL;

        cb(iface, status);

        return 0;
}


static void select_hw_mode2(struct hostapd_iface *iface, int status)
{
        int ret = status;
        if (ret)
                goto fail;

        if (iface->current_mode == NULL) {
                hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
                               HOSTAPD_LEVEL_WARNING,
                               "Hardware does not support configured channel");
                ret = -1;
                goto fail;
        }

        if (hostapd_prepare_rates(iface->bss[0], iface->current_mode)) {
                printf("Failed to prepare rates table.\n");
                hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
                                           HOSTAPD_LEVEL_WARNING,
                                           "Failed to prepare rates table.");
                ret = -1;
                goto fail;
        }

        ret = hostapd_passive_scan(iface->bss[0], 0,
                                   iface->conf->passive_scan_mode,
                                   iface->conf->passive_scan_interval,
                                   iface->conf->passive_scan_listen,
                                   NULL, NULL);
        if (ret) {
                printf("Could not set passive scanning: %s\n", strerror(ret));
                ret = 0;
        }

fail:
        select_hw_mode_finalize(iface, ret);
}


static void select_hw_mode2_handler(void *eloop_data, void *user_ctx)
{
        struct hostapd_iface *iface = eloop_data;

        select_hw_mode2(iface, 0);
}


static int select_hw_mode1(struct hostapd_iface *iface)
{
        int i, j, ok;

        if (iface->num_hw_features < 1)
                return -1;

        iface->current_mode = NULL;
        for (i = 0; i < iface->num_hw_features; i++) {
                struct hostapd_hw_modes *mode = &iface->hw_features[i];
                if (mode->mode == (int) iface->conf->hw_mode) {
                        iface->current_mode = mode;
                        break;
                }
        }

        if (iface->current_mode == NULL) {
                printf("Hardware does not support configured mode\n");
                hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,
                               HOSTAPD_LEVEL_WARNING,
                               "Hardware does not support configured mode "
                               "(%d)", (int) iface->conf->hw_mode);
                return -1;
        }

        ok = 0;
        for (j = 0; j < iface->current_mode->num_channels; j++) {
                struct hostapd_channel_data *chan =
                        &iface->current_mode->channels[j];
                if ((chan->flag & HOSTAPD_CHAN_W_SCAN) &&
                    (chan->chan == iface->conf->channel)) {
                        ok = 1;
                        break;
                }
        }
        if (ok == 0 && iface->conf->channel != 0) {
                hostapd_logger(iface->bss[0], NULL,
                               HOSTAPD_MODULE_IEEE80211,
                               HOSTAPD_LEVEL_WARNING,
                               "Configured channel (%d) not found from the "
                               "channel list of current mode (%d) %s",
                               iface->conf->channel,
                               iface->current_mode->mode,
                               hostapd_hw_mode_txt(iface->current_mode->mode));
                iface->current_mode = NULL;
        }

        /*
         * Calls select_hw_mode2() via a handler, so that the function is
         * always executed from eloop.
         */
        eloop_register_timeout(0, 0, select_hw_mode2_handler, iface, NULL);
        return 0;
}


static void select_hw_mode_start(void *eloop_data, void *user_ctx)
{
        struct hostapd_iface *iface = (struct hostapd_iface *)eloop_data;

        int ret;

        ret = select_hw_mode1(iface);
        if (ret)
                select_hw_mode_finalize(iface, ret);
}


int hostapd_select_hw_mode_start(struct hostapd_iface *iface,
                                 hostapd_iface_cb cb)
{
        if (iface->hw_mode_sel_cb) {
                wpa_printf(MSG_DEBUG,
                           "%s: Hardware mode select already in progress.",
                           iface->bss[0]->conf->iface);
                return -1;
        }

        iface->hw_mode_sel_cb = cb;

        eloop_register_timeout(0, 0, select_hw_mode_start, iface, NULL);

        return 0;
}


int hostapd_select_hw_mode_stop(struct hostapd_iface *iface)
{
        return select_hw_mode_finalize(iface, -1);
}


const char * hostapd_hw_mode_txt(int mode)
{
        switch (mode) {
        case HOSTAPD_MODE_IEEE80211A:
                return "IEEE 802.11a";
        case HOSTAPD_MODE_IEEE80211B:
                return "IEEE 802.11b";
        case HOSTAPD_MODE_IEEE80211G:
                return "IEEE 802.11g";
        default:
                return "UNKNOWN";
        }
}


int hostapd_hw_get_freq(struct hostapd_data *hapd, int chan)
{
        int i;

        if (!hapd->iface->current_mode)
                return 0;

        for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
                struct hostapd_channel_data *ch =
                        &hapd->iface->current_mode->channels[i];
                if (ch->chan == chan)
                        return ch->freq;
        }

        return 0;
}


int hostapd_hw_get_channel(struct hostapd_data *hapd, int freq)
{
        int i;

        if (!hapd->iface->current_mode)
                return 0;

        for (i = 0; i < hapd->iface->current_mode->num_channels; i++) {
                struct hostapd_channel_data *ch =
                        &hapd->iface->current_mode->channels[i];
                if (ch->freq == freq)
                        return ch->chan;
        }

        return 0;
}

---