DPP2: GAS comeback request processing for Configurator over TCP

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

diff --git a/src/common/dpp_tcp.c b/src/common/dpp_tcp.c
index de52d3afaf81343b4c86c4b701d6de2db960c4c7..39cb6fd3e93de4cd48d3cd68e08ca427309e8c21 100644 (file)
--- a/src/common/dpp_tcp.c
+++ b/src/common/dpp_tcp.c
@@ -38,7 +38,9 @@ struct dpp_connection {
        unsigned int on_tcp_tx_complete_gas_done:1;
        unsigned int on_tcp_tx_complete_remove:1;
        unsigned int on_tcp_tx_complete_auth_ok:1;
+       unsigned int gas_comeback_in_progress:1;
        u8 gas_dialog_token;
+       struct wpabuf *gas_resp;
 };
 
 /* Remote Controller */
@@ -88,6 +90,7 @@ static void dpp_connection_free(struct dpp_connection *conn)
        eloop_cancel_timeout(dpp_tcp_gas_query_comeback, conn, NULL);
        wpabuf_free(conn->msg);
        wpabuf_free(conn->msg_out);
+       wpabuf_free(conn->gas_resp);
        dpp_auth_deinit(conn->auth);
        os_free(conn);
 }
@@ -976,14 +979,91 @@ static int dpp_controller_rx_action(struct dpp_connection *conn, const u8 *msg,
 }
 
 
+static int dpp_tcp_send_comeback_delay(struct dpp_connection *conn, u8 action)
+{
+       struct wpabuf *buf;
+       size_t len = 18;
+
+       if (action == WLAN_PA_GAS_COMEBACK_RESP)
+               len++;
+
+       buf = wpabuf_alloc(4 + len);
+       if (!buf)
+               return -1;
+
+       wpabuf_put_be32(buf, len);
+
+       wpabuf_put_u8(buf, action);
+       wpabuf_put_u8(buf, conn->gas_dialog_token);
+       wpabuf_put_le16(buf, WLAN_STATUS_SUCCESS);
+       if (action == WLAN_PA_GAS_COMEBACK_RESP)
+               wpabuf_put_u8(buf, 0);
+       wpabuf_put_le16(buf, 500); /* GAS Comeback Delay */
+
+       dpp_write_adv_proto(buf);
+       wpabuf_put_le16(buf, 0); /* Query Response Length */
+
+       /* Send Config Response over TCP */
+       wpa_hexdump_buf(MSG_MSGDUMP, "DPP: Outgoing TCP message", buf);
+       wpabuf_free(conn->msg_out);
+       conn->msg_out_pos = 0;
+       conn->msg_out = buf;
+       dpp_tcp_send(conn);
+       return 0;
+}
+
+
+static int dpp_tcp_send_gas_resp(struct dpp_connection *conn, u8 action,
+                                struct wpabuf *resp)
+{
+       struct wpabuf *buf;
+       size_t len;
+
+       if (!resp)
+               return -1;
+
+       len = 18 + wpabuf_len(resp);
+       if (action == WLAN_PA_GAS_COMEBACK_RESP)
+               len++;
+
+       buf = wpabuf_alloc(4 + len);
+       if (!buf) {
+               wpabuf_free(resp);
+               return -1;
+       }
+
+       wpabuf_put_be32(buf, len);
+
+       wpabuf_put_u8(buf, action);
+       wpabuf_put_u8(buf, conn->gas_dialog_token);
+       wpabuf_put_le16(buf, WLAN_STATUS_SUCCESS);
+       if (action == WLAN_PA_GAS_COMEBACK_RESP)
+               wpabuf_put_u8(buf, 0);
+       wpabuf_put_le16(buf, 0); /* GAS Comeback Delay */
+
+       dpp_write_adv_proto(buf);
+       dpp_write_gas_query(buf, resp);
+       wpabuf_free(resp);
+
+       /* Send Config Response over TCP; GAS fragmentation is taken care of by
+        * the Relay */
+       wpa_hexdump_buf(MSG_MSGDUMP, "DPP: Outgoing TCP message", buf);
+       wpabuf_free(conn->msg_out);
+       conn->msg_out_pos = 0;
+       conn->msg_out = buf;
+       conn->on_tcp_tx_complete_gas_done = 1;
+       dpp_tcp_send(conn);
+       return 0;
+}
+
+
 static int dpp_controller_rx_gas_req(struct dpp_connection *conn, const u8 *msg,
                                     size_t len)
 {
        const u8 *pos, *end, *next;
-       u8 dialog_token;
        const u8 *adv_proto;
        u16 slen;
-       struct wpabuf *resp, *buf;
+       struct wpabuf *resp;
        struct dpp_authentication *auth = conn->auth;
 
        if (len < 1 + 2)
@@ -1001,7 +1081,7 @@ static int dpp_controller_rx_gas_req(struct dpp_connection *conn, const u8 *msg,
        pos = msg;
        end = msg + len;
 
-       dialog_token = *pos++;
+       conn->gas_dialog_token = *pos++;
        adv_proto = pos++;
        slen = *pos++;
        if (*adv_proto != WLAN_EID_ADV_PROTO ||
@@ -1028,57 +1108,53 @@ static int dpp_controller_rx_gas_req(struct dpp_connection *conn, const u8 *msg,
        resp = dpp_conf_req_rx(auth, pos, slen);
        if (!resp && auth->waiting_cert) {
                wpa_printf(MSG_DEBUG, "DPP: Certificate not yet ready");
-               buf = wpabuf_alloc(4 + 18);
-               if (!buf)
-                       return -1;
+               conn->gas_comeback_in_progress = 1;
+               return dpp_tcp_send_comeback_delay(conn,
+                                                  WLAN_PA_GAS_INITIAL_RESP);
+       }
 
-               wpabuf_put_be32(buf, 18);
+       return dpp_tcp_send_gas_resp(conn, WLAN_PA_GAS_INITIAL_RESP, resp);
+}
 
-               wpabuf_put_u8(buf, WLAN_PA_GAS_INITIAL_RESP);
-               wpabuf_put_u8(buf, dialog_token);
-               wpabuf_put_le16(buf, WLAN_STATUS_SUCCESS);
-               wpabuf_put_le16(buf, 500); /* GAS Comeback Delay */
 
-               dpp_write_adv_proto(buf);
-               wpabuf_put_le16(buf, 0); /* Query Response Length */
+static int dpp_controller_rx_gas_comeback_req(struct dpp_connection *conn,
+                                             const u8 *msg, size_t len)
+{
+       u8 dialog_token;
+       struct dpp_authentication *auth = conn->auth;
+       struct wpabuf *resp;
 
-               /* Send Config Response over TCP */
-               wpa_hexdump_buf(MSG_MSGDUMP, "DPP: Outgoing TCP message", buf);
-               wpabuf_free(conn->msg_out);
-               conn->msg_out_pos = 0;
-               conn->msg_out = buf;
-               dpp_tcp_send(conn);
-               return 0;
-       }
-       if (!resp)
+       if (len < 1)
                return -1;
 
-       buf = wpabuf_alloc(4 + 18 + wpabuf_len(resp));
-       if (!buf) {
-               wpabuf_free(resp);
+       wpa_printf(MSG_DEBUG,
+                  "DPP: Received DPP Configuration Request over TCP (comeback)");
+
+       if (!auth || (!conn->ctrl && !auth->configurator) ||
+           (!auth->auth_success && !auth->reconfig_success) ||
+           !conn->gas_comeback_in_progress) {
+               wpa_printf(MSG_DEBUG, "DPP: No matching exchange in progress");
                return -1;
        }
 
-       wpabuf_put_be32(buf, 18 + wpabuf_len(resp));
-
-       wpabuf_put_u8(buf, WLAN_PA_GAS_INITIAL_RESP);
-       wpabuf_put_u8(buf, dialog_token);
-       wpabuf_put_le16(buf, WLAN_STATUS_SUCCESS);
-       wpabuf_put_le16(buf, 0); /* GAS Comeback Delay */
+       dialog_token = msg[0];
+       if (dialog_token != conn->gas_dialog_token) {
+               wpa_printf(MSG_DEBUG, "DPP: Dialog token mismatch (%u != %u)",
+                          dialog_token, conn->gas_dialog_token);
+               return -1;
+       }
 
-       dpp_write_adv_proto(buf);
-       dpp_write_gas_query(buf, resp);
-       wpabuf_free(resp);
+       if (!conn->gas_resp) {
+               wpa_printf(MSG_DEBUG, "DPP: Certificate not yet ready");
+               return dpp_tcp_send_comeback_delay(conn,
+                                                  WLAN_PA_GAS_COMEBACK_RESP);
+       }
 
-       /* Send Config Response over TCP; GAS fragmentation is taken care of by
-        * the Relay */
-       wpa_hexdump_buf(MSG_MSGDUMP, "DPP: Outgoing TCP message", buf);
-       wpabuf_free(conn->msg_out);
-       conn->msg_out_pos = 0;
-       conn->msg_out = buf;
-       conn->on_tcp_tx_complete_gas_done = 1;
-       dpp_tcp_send(conn);
-       return 0;
+       wpa_printf(MSG_DEBUG,
+                  "DPP: Configuration response is ready to be sent out");
+       resp = conn->gas_resp;
+       conn->gas_resp = NULL;
+       return dpp_tcp_send_gas_resp(conn, WLAN_PA_GAS_COMEBACK_RESP, resp);
 }
 
 
@@ -1369,6 +1445,11 @@ static void dpp_controller_rx(int sd, void *eloop_ctx, void *sock_ctx)
                                    wpabuf_len(conn->msg) - 1) < 0)
                        dpp_connection_remove(conn);
                break;
+       case WLAN_PA_GAS_COMEBACK_REQ:
+               if (dpp_controller_rx_gas_comeback_req(
+                           conn, pos + 1, wpabuf_len(conn->msg) - 1) < 0)
+                       dpp_connection_remove(conn);
+               break;
        default:
                wpa_printf(MSG_DEBUG, "DPP: Ignore unsupported message type %u",
                           *pos);