DPP: Move GAS encapsulation into dpp_build_conf_req()

Avoid duplicated code in each user of dpp_build_conf_req() by moving the
common encapsulation case into this helper function.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>

src/ap/dpp_hostapd.c

@@ -755,7 +755,7 @@ fail2:
 static void hostapd_dpp_start_gas_client(struct hostapd_data *hapd)
 {
 	struct dpp_authentication *auth = hapd->dpp_auth;
-	struct wpabuf *buf, *conf_req;
+	struct wpabuf *buf;
 	char json[100];
 	int res;
 	int netrole_ap = 1;
@@ -767,34 +767,13 @@ static void hostapd_dpp_start_gas_client(struct hostapd_data *hapd)
 		    netrole_ap ? "ap" : "sta");
 	wpa_printf(MSG_DEBUG, "DPP: GAS Config Attributes: %s", json);
 
-	conf_req = dpp_build_conf_req(auth, json);
+	buf = dpp_build_conf_req(auth, json);
-	if (!conf_req) {
+	if (!buf) {
 		wpa_printf(MSG_DEBUG,
 			   "DPP: No configuration request data available");
 		return;
 	}
 
-	buf = gas_build_initial_req(0, 10 + 2 + wpabuf_len(conf_req));
-	if (!buf) {
-		wpabuf_free(conf_req);
-		return;
-	}
-
-	/* Advertisement Protocol IE */
-	wpabuf_put_u8(buf, WLAN_EID_ADV_PROTO);
-	wpabuf_put_u8(buf, 8); /* Length */
-	wpabuf_put_u8(buf, 0x7f);
-	wpabuf_put_u8(buf, WLAN_EID_VENDOR_SPECIFIC);
-	wpabuf_put_u8(buf, 5);
-	wpabuf_put_be24(buf, OUI_WFA);
-	wpabuf_put_u8(buf, DPP_OUI_TYPE);
-	wpabuf_put_u8(buf, 0x01);
-
-	/* GAS Query */
-	wpabuf_put_le16(buf, wpabuf_len(conf_req));
-	wpabuf_put_buf(buf, conf_req);
-	wpabuf_free(conf_req);
-
 	wpa_printf(MSG_DEBUG, "DPP: GAS request to " MACSTR " (freq %u MHz)",
 		   MAC2STR(auth->peer_mac_addr), auth->curr_freq);
 

src/common/dpp.c

@@ -19,6 +19,7 @@
 #include "common/ieee802_11_common.h"
 #include "common/ieee802_11_defs.h"
 #include "common/wpa_ctrl.h"
+#include "common/gas.h"
 #include "crypto/crypto.h"
 #include "crypto/random.h"
 #include "crypto/aes.h"
@@ -2228,7 +2229,7 @@ fail:
 }
 
 
-struct wpabuf * dpp_build_conf_req(struct dpp_authentication *auth,
+static struct wpabuf * dpp_build_conf_req_attr(struct dpp_authentication *auth,
 					       const char *json)
 {
 	size_t nonce_len;
@@ -2333,6 +2334,55 @@ fail:
 }
 
 
+static void dpp_write_adv_proto(struct wpabuf *buf)
+{
+	/* Advertisement Protocol IE */
+	wpabuf_put_u8(buf, WLAN_EID_ADV_PROTO);
+	wpabuf_put_u8(buf, 8); /* Length */
+	wpabuf_put_u8(buf, 0x7f);
+	wpabuf_put_u8(buf, WLAN_EID_VENDOR_SPECIFIC);
+	wpabuf_put_u8(buf, 5);
+	wpabuf_put_be24(buf, OUI_WFA);
+	wpabuf_put_u8(buf, DPP_OUI_TYPE);
+	wpabuf_put_u8(buf, 0x01);
+}
+
+
+static void dpp_write_gas_query(struct wpabuf *buf, struct wpabuf *query)
+{
+	/* GAS Query */
+	wpabuf_put_le16(buf, wpabuf_len(query));
+	wpabuf_put_buf(buf, query);
+}
+
+
+struct wpabuf * dpp_build_conf_req(struct dpp_authentication *auth,
+				   const char *json)
+{
+	struct wpabuf *buf, *conf_req;
+
+	conf_req = dpp_build_conf_req_attr(auth, json);
+	if (!conf_req) {
+		wpa_printf(MSG_DEBUG,
+			   "DPP: No configuration request data available");
+		return NULL;
+	}
+
+	buf = gas_build_initial_req(0, 10 + 2 + wpabuf_len(conf_req));
+	if (!buf) {
+		wpabuf_free(conf_req);
+		return NULL;
+	}
+
+	dpp_write_adv_proto(buf);
+	dpp_write_gas_query(buf, conf_req);
+	wpabuf_free(conf_req);
+	wpa_hexdump_buf(MSG_MSGDUMP, "DPP: GAS Config Request", buf);
+
+	return buf;
+}
+
+
 static void dpp_auth_success(struct dpp_authentication *auth)
 {
 	wpa_printf(MSG_DEBUG,

wpa_supplicant/dpp_supplicant.c

@@ -1066,7 +1066,7 @@ fail2:
 static void wpas_dpp_start_gas_client(struct wpa_supplicant *wpa_s)
 {
 	struct dpp_authentication *auth = wpa_s->dpp_auth;
-	struct wpabuf *buf, *conf_req;
+	struct wpabuf *buf;
 	char json[100];
 	int res;
 
@@ -1087,34 +1087,13 @@ static void wpas_dpp_start_gas_client(struct wpa_supplicant *wpa_s)
 	offchannel_send_action_done(wpa_s);
 	wpas_dpp_listen_stop(wpa_s);
 
-	conf_req = dpp_build_conf_req(auth, json);
+	buf = dpp_build_conf_req(auth, json);
-	if (!conf_req) {
+	if (!buf) {
 		wpa_printf(MSG_DEBUG,
 			   "DPP: No configuration request data available");
 		return;
 	}
 
-	buf = gas_build_initial_req(0, 10 + 2 + wpabuf_len(conf_req));
-	if (!buf) {
-		wpabuf_free(conf_req);
-		return;
-	}
-
-	/* Advertisement Protocol IE */
-	wpabuf_put_u8(buf, WLAN_EID_ADV_PROTO);
-	wpabuf_put_u8(buf, 8); /* Length */
-	wpabuf_put_u8(buf, 0x7f);
-	wpabuf_put_u8(buf, WLAN_EID_VENDOR_SPECIFIC);
-	wpabuf_put_u8(buf, 5);
-	wpabuf_put_be24(buf, OUI_WFA);
-	wpabuf_put_u8(buf, DPP_OUI_TYPE);
-	wpabuf_put_u8(buf, 0x01);
-
-	/* GAS Query */
-	wpabuf_put_le16(buf, wpabuf_len(conf_req));
-	wpabuf_put_buf(buf, conf_req);
-	wpabuf_free(conf_req);
-
 	wpa_printf(MSG_DEBUG, "DPP: GAS request to " MACSTR " (freq %u MHz)",
 		   MAC2STR(auth->peer_mac_addr), auth->curr_freq);