diff --git a/hostapd/hw_features.c b/hostapd/hw_features.c index 6cf043765..7d4180376 100644 --- a/hostapd/hw_features.c +++ b/hostapd/hw_features.c @@ -170,6 +170,73 @@ static int hostapd_prepare_rates(struct hostapd_data *hapd, } +#ifdef CONFIG_IEEE80211N +static int ieee80211n_allowed_ht40_channel_pair(struct hostapd_iface *iface) +{ + int sec_chan, ok, j, first; + int allowed[] = { 36, 44, 52, 60, 100, 108, 116, 124, 132, 149, 157, + 184, 192 }; + size_t k; + + if (!iface->conf->secondary_channel) + return 1; /* HT40 not used */ + + sec_chan = iface->conf->channel + iface->conf->secondary_channel * 4; + wpa_printf(MSG_DEBUG, "HT40: control channel: %d " + "secondary channel: %d", + iface->conf->channel, sec_chan); + + /* Verify that HT40 secondary channel is an allowed 20 MHz + * channel */ + 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_DISABLED) && + chan->chan == sec_chan) { + ok = 1; + break; + } + } + if (!ok) { + wpa_printf(MSG_ERROR, "HT40 secondary channel %d not allowed", + sec_chan); + return 0; + } + + /* + * Verify that HT40 primary,secondary channel pair is allowed per + * IEEE 802.11n Annex J. This is only needed for 5 GHz band since + * 2.4 GHz rules allow all cases where the secondary channel fits into + * the list of allowed channels (already checked above). + */ + if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A) + return 1; + + if (iface->conf->secondary_channel > 0) + first = iface->conf->channel; + else + first = sec_chan; + + ok = 0; + for (k = 0; k < sizeof(allowed) / sizeof(allowed[0]); k++) { + if (first == allowed[k]) { + ok = 1; + break; + } + } + if (!ok) { + wpa_printf(MSG_ERROR, "HT40 channel pair (%d, %d) not allowed", + iface->conf->channel, + iface->conf->secondary_channel); + return 0; + } + + return 1; +} +#endif /* CONFIG_IEEE80211N */ + + /** * hostapd_select_hw_mode - Select the hardware mode * @iface: Pointer to interface data. @@ -233,6 +300,11 @@ int hostapd_select_hw_mode(struct hostapd_iface *iface) return -1; } +#ifdef CONFIG_IEEE80211N + if (!ieee80211n_allowed_ht40_channel_pair(iface)) + return -1; +#endif /* CONFIG_IEEE80211N */ + if (hostapd_prepare_rates(iface->bss[0], iface->current_mode)) { wpa_printf(MSG_ERROR, "Failed to prepare rates table."); hostapd_logger(iface->bss[0], NULL, HOSTAPD_MODULE_IEEE80211,