EAP-TNC: Add Flags field into fragment acknowledgement

TNC IF-T is somewhat unclear on this are, but
draft-hanna-nea-pt-eap-00.txt, which is supposed to define the same
protocol, is clearer on the Flags field being included.

This change breaks interoperability with the old implementation if
EAP-TNC fragmentation is used. The old version would not accept
the acknowledgement message with the added Flags octet while the
new version accepts messagss with with both options.

src/eap_peer/eap_tnc.c

@@ -73,12 +73,13 @@ static struct wpabuf * eap_tnc_build_frag_ack(u8 id, u8 code)
 {
 	struct wpabuf *msg;
 
-	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TNC, 0, code, id);
+	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TNC, 1, code, id);
 	if (msg == NULL) {
 		wpa_printf(MSG_ERROR, "EAP-TNC: Failed to allocate memory "
 			   "for fragment ack");
 		return NULL;
 	}
+	wpabuf_put_u8(msg, EAP_TNC_VERSION); /* Flags */
 
 	wpa_printf(MSG_DEBUG, "EAP-TNC: Send fragment ack");
 

src/eap_server/eap_tnc.c

@@ -173,12 +173,13 @@ static struct wpabuf * eap_tnc_build_frag_ack(u8 id, u8 code)
 {
 	struct wpabuf *msg;
 
-	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TNC, 0, code, id);
+	msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TNC, 1, code, id);
 	if (msg == NULL) {
 		wpa_printf(MSG_ERROR, "EAP-TNC: Failed to allocate memory "
 			   "for fragment ack");
 		return NULL;
 	}
+	wpabuf_put_u8(msg, EAP_TNC_VERSION); /* Flags */
 
 	wpa_printf(MSG_DEBUG, "EAP-TNC: Send fragment ack");