Add support for advertising UTF-8 SSID extended capability

This field can be used to indicate that UTF-8 encoding is used in the
SSID field.

Signed-hostap: Jouni Malinen <j@w1.fi>

hostapd/config_file.c

@@ -1780,6 +1780,8 @@ static int hostapd_config_fill(struct hostapd_config *conf,
 				bss->ssid.ssid_set = 1;
 			}
 			os_free(str);
+		} else if (os_strcmp(buf, "utf8_ssid") == 0) {
+			bss->ssid.utf8_ssid = atoi(pos) > 0;
 		} else if (os_strcmp(buf, "macaddr_acl") == 0) {
 			bss->macaddr_acl = atoi(pos);
 			if (bss->macaddr_acl != ACCEPT_UNLESS_DENIED &&

hostapd/hostapd.conf

@@ -90,6 +90,9 @@ ssid=test
 #ssid2=74657374
 #ssid2=P"hello\nthere"
 
+# UTF-8 SSID: Whether the SSID is to be interpreted using UTF-8 encoding
+#utf8_ssid=1
+
 # Country code (ISO/IEC 3166-1). Used to set regulatory domain.
 # Set as needed to indicate country in which device is operating.
 # This can limit available channels and transmit power.

src/ap/ap_config.h

@@ -51,7 +51,8 @@ typedef enum hostap_security_policy {
 struct hostapd_ssid {
 	u8 ssid[HOSTAPD_MAX_SSID_LEN];
 	size_t ssid_len;
-	int ssid_set;
+	unsigned int ssid_set:1;
+	unsigned int utf8_ssid:1;
 
 	char vlan[IFNAMSIZ + 1];
 	secpolicy security_policy;

src/ap/ieee802_11_shared.c

@@ -175,6 +175,8 @@ u8 * hostapd_eid_ext_capab(struct hostapd_data *hapd, u8 *eid)
 		len = 4;
 	if (len < 3 && hapd->conf->wnm_sleep_mode)
 		len = 3;
+	if (len < 7 && hapd->conf->ssid.utf8_ssid)
+		len = 7;
 	if (len == 0)
 		return eid;
 
@@ -206,6 +208,18 @@ u8 * hostapd_eid_ext_capab(struct hostapd_data *hapd, u8 *eid)
 		*pos |= 0x80; /* Bit 39 - TDLS Channel Switching Prohibited */
 	pos++;
 
+	if (len < 6)
+		return pos;
+	*pos = 0x00;
+	pos++;
+
+	if (len < 7)
+		return pos;
+	*pos = 0x00;
+	if (hapd->conf->ssid.utf8_ssid)
+		*pos |= 0x01; /* Bit 48 - UTF-8 SSID */
+	pos++;
+
 	return pos;
 }