switch: fix dummy_teid handling

when using GTP-C ingress/egress split configuration, echo-request messages MUST not be forwarded and
rather handled directly by receiving peer.

Author: acassen

VERSION

@@ -1 +1 @@
-1.0.6
+1.0.7pre0

lib/config.h

@@ -25,7 +25,7 @@
 #define LOG_FACILITY_MAX        7
 #define PROG                    "gtp-guard"
 #define PROG_PID_FILE		"/var/run/gtp-guard.pid"
-#define VERSION_STRING PROG	" v1.0.6 (2024/06/23)"
+#define VERSION_STRING PROG	" v1.0.7pre0 (2024/06/23)"
 #define COPYRIGHT_STRING	"Copyright (C) 2023-2024 Alexandre Cassen, <acassen@gmail.com>"
 
 

src/gtp_switch.c

@@ -137,8 +137,8 @@ gtp_switch_ingress_process(gtp_server_worker_t *w, struct sockaddr_storage *addr
 
 	/* Set destination address */
 	gtp_switch_fwd_addr_get(teid, addr_from, &addr_to);
-	gtp_server_send(w, fd
-			 , (teid->type == 0xff) ? (struct sockaddr_in *) addr_from : &addr_to);
+	gtp_server_send(w, TEID_IS_DUMMY(teid) ? w->fd : fd
+			 , TEID_IS_DUMMY(teid) ? (struct sockaddr_in *) addr_from : &addr_to);
 	gtpc_switch_handle_post(w, teid);
 
 	return 0;

src/include/gtp_teid.h

@@ -42,6 +42,9 @@ enum gtp_teid_flags {
 	GTP_TEID_FL_XDP_SET,
 };
 
+/* Defines */
+#define TEID_IS_DUMMY(X)	((X)->type == 0xff)
+
 /* GTP Connection tracking */
 typedef struct _gtp_teid {
 	uint8_t			version;	/* GTPv1 or GTPv2 */