diff --git a/daemon/gtp.h b/daemon/gtp.h
new file mode 100644
index 0000000..f2acd36
--- /dev/null
+++ b/daemon/gtp.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#pragma once
+#include <stdint.h>
+
+/* General GTP protocol related definitions. */
+
+#define GTP0_PORT	3386
+#define GTP1U_PORT	2152
+
+#define GTP_TPDU	255
+
+struct gtp0_header {	/* According to GSM TS 09.60. */
+	uint8_t	flags;
+	uint8_t	type;
+	uint16_t length;
+	uint16_t seq;
+	uint16_t flow;
+	uint8_t	number;
+	uint8_t	spare[3];
+	uint64_t tid;
+} __attribute__ ((packed));
+
+struct gtp1_header {	/* According to 3GPP TS 29.060. */
+	uint8_t	flags;
+	uint8_t	type;
+	uint16_t length;
+	uint32_t tid;
+} __attribute__ ((packed));
+
+#define GTP1_F_NPDU	0x01
+#define GTP1_F_SEQ	0x02
+#define GTP1_F_EXTHDR	0x04
+#define GTP1_F_MASK	0x07