Add AP mode support for HT 20/40 co-ex Action frame

[mech_eap.git] / src / ap / ieee802_11_ht.c

diff --git a/src/ap/ieee802_11_ht.c b/src/ap/ieee802_11_ht.c
index 38caaed..c0a7cd4 100644 (file)
--- a/src/ap/ieee802_11_ht.c
+++ b/src/ap/ieee802_11_ht.c
@@ -175,6 +175,117 @@ int hostapd_ht_operation_update(struct hostapd_iface *iface)
 }
 
 
+static int is_40_allowed(struct hostapd_iface *iface, int channel)
+{
+       int pri_freq, sec_freq;
+       int affected_start, affected_end;
+       int pri = 2407 + 5 * channel;
+
+       if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G)
+               return 1;
+
+       pri_freq = hostapd_hw_get_freq(iface->bss[0], iface->conf->channel);
+
+       if (iface->conf->secondary_channel > 0)
+               sec_freq = pri_freq + 20;
+       else
+               sec_freq = pri_freq - 20;
+
+       affected_start = (pri_freq + sec_freq) / 2 - 25;
+       affected_end = (pri_freq + sec_freq) / 2 + 25;
+       if ((pri < affected_start || pri > affected_end))
+               return 1; /* not within affected channel range */
+
+       wpa_printf(MSG_ERROR, "40 MHz affected channel range: [%d,%d] MHz",
+                  affected_start, affected_end);
+       wpa_printf(MSG_ERROR, "Neighboring BSS: freq=%d", pri);
+       return 0;
+}
+
+
+void hostapd_2040_coex_action(struct hostapd_data *hapd,
+                             const struct ieee80211_mgmt *mgmt, size_t len)
+{
+       struct hostapd_iface *iface = hapd->iface;
+       struct ieee80211_2040_bss_coex_ie *bc_ie;
+       struct ieee80211_2040_intol_chan_report *ic_report;
+       int is_ht_allowed = 1;
+       int i;
+       const u8 *data = (const u8 *) &mgmt->u.action.u.public_action.action;
+       size_t hdr_len;
+
+       hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
+                      HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d",
+                      mgmt->u.action.u.public_action.action);
+
+       if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET))
+               return;
+
+       hdr_len = data - (u8 *) mgmt;
+       if (hdr_len > len)
+               return;
+       data++;
+
+       bc_ie = (struct ieee80211_2040_bss_coex_ie *) &data[0];
+       ic_report = (struct ieee80211_2040_intol_chan_report *)
+               (&data[0] + sizeof(*bc_ie));
+
+       if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) {
+               hostapd_logger(hapd, mgmt->sa,
+                              HOSTAPD_MODULE_IEEE80211,
+                              HOSTAPD_LEVEL_DEBUG,
+                              "20 MHz BSS width request bit is set in BSS coexistence information field");
+               is_ht_allowed = 0;
+       }
+
+       if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) {
+               hostapd_logger(hapd, mgmt->sa,
+                              HOSTAPD_MODULE_IEEE80211,
+                              HOSTAPD_LEVEL_DEBUG,
+                              "40 MHz intolerant bit is set in BSS coexistence information field");
+               is_ht_allowed = 0;
+       }
+
+       if (ic_report &&
+           (ic_report->element_id == WLAN_EID_20_40_BSS_INTOLERANT)) {
+               /* Go through the channel report to find any BSS there in the
+                * affected channel range */
+               for (i = 0; i < ic_report->length - 1; i++) {
+                       if (is_40_allowed(iface, ic_report->variable[i]))
+                               continue;
+                       hostapd_logger(hapd, mgmt->sa,
+                                      HOSTAPD_MODULE_IEEE80211,
+                                      HOSTAPD_LEVEL_DEBUG,
+                                      "20_40_INTOLERANT channel %d reported",
+                                      ic_report->variable[i]);
+                       is_ht_allowed = 0;
+                       break;
+               }
+       }
+
+       if (!is_ht_allowed &&
+           (iface->drv_flags & WPA_DRIVER_FLAGS_HT_2040_COEX)) {
+               if (iface->conf->secondary_channel) {
+                       hostapd_logger(hapd, mgmt->sa,
+                                      HOSTAPD_MODULE_IEEE80211,
+                                      HOSTAPD_LEVEL_INFO,
+                                      "Switching to 20 MHz operation");
+                       iface->conf->secondary_channel = 0;
+                       ieee802_11_set_beacons(iface);
+               }
+               if (!iface->num_sta_ht40_intolerant) {
+                       unsigned int delay_time;
+                       delay_time = OVERLAPPING_BSS_TRANS_DELAY_FACTOR *
+                               iface->conf->obss_interval;
+                       eloop_cancel_timeout(ap_ht2040_timeout, hapd->iface,
+                                            NULL);
+                       eloop_register_timeout(delay_time, 0, ap_ht2040_timeout,
+                                              hapd->iface, NULL);
+               }
+       }
+}
+
+
 u16 copy_sta_ht_capab(struct hostapd_data *hapd, struct sta_info *sta,
                      const u8 *ht_capab, size_t ht_capab_len)
 {