Add option to ignore Probe Request frames when RSSI is too low

Add a new hostapd configuration parameters rssi_ignore_probe_request to
ignore Probe Request frames received with too low RSSI.

Signed-off-by: John Crispin <john@phrozen.org>

hostapd/config_file.c

@@ -4450,6 +4450,8 @@ static int hostapd_config_fill(struct hostapd_config *conf,
 		conf->rssi_reject_assoc_rssi = atoi(pos);
 	} else if (os_strcmp(buf, "rssi_reject_assoc_timeout") == 0) {
 		conf->rssi_reject_assoc_timeout = atoi(pos);
+	} else if (os_strcmp(buf, "rssi_ignore_probe_request") == 0) {
+		conf->rssi_ignore_probe_request = atoi(pos);
 	} else if (os_strcmp(buf, "pbss") == 0) {
 		bss->pbss = atoi(pos);
 	} else if (os_strcmp(buf, "transition_disable") == 0) {

hostapd/hostapd.conf

@@ -2735,6 +2735,10 @@ own_ip_addr=127.0.0.1
 # threshold (range: 0..255, default=30).
 #rssi_reject_assoc_timeout=30
 
+# Ignore Probe Request frames if RSSI is below given threshold (in dBm)
+# Allowed range: -60 to -90 dBm; default = 0 (rejection disabled)
+#rssi_ignore_probe_request=-75
+
 ##### Fast Session Transfer (FST) support #####################################
 #
 # The options in this section are only available when the build configuration

src/ap/ap_config.h

@@ -1039,6 +1039,7 @@ struct hostapd_config {
 
 	int rssi_reject_assoc_rssi;
 	int rssi_reject_assoc_timeout;
+	int rssi_ignore_probe_request;
 
 #ifdef CONFIG_AIRTIME_POLICY
 	enum {

src/ap/beacon.c

@@ -818,6 +818,10 @@ void handle_probe_req(struct hostapd_data *hapd,
 	size_t csa_offs_len;
 	struct radius_sta rad_info;
 
+	if (hapd->iconf->rssi_ignore_probe_request && ssi_signal &&
+	    ssi_signal < hapd->iconf->rssi_ignore_probe_request)
+		return;
+
 	if (len < IEEE80211_HDRLEN)
 		return;
 	ie = ((const u8 *) mgmt) + IEEE80211_HDRLEN;