diff --git a/src/s1ap/asn1c/asnGenFiles/BIT_STRING.h b/src/s1ap/asn1c/asnGenFiles/BIT_STRING.h
new file mode 100644
index 0000000..c1bdbbc
--- /dev/null
+++ b/src/s1ap/asn1c/asnGenFiles/BIT_STRING.h
@@ -0,0 +1,48 @@
+/*-
+ * Copyright (c) 2003-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#ifndef	_BIT_STRING_H_
+#define	_BIT_STRING_H_
+
+#include <OCTET_STRING.h>	/* Some help from OCTET STRING */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct BIT_STRING_s {
+	uint8_t *buf;	/* BIT STRING body */
+	size_t size;	/* Size of the above buffer */
+
+	int bits_unused;/* Unused trailing bits in the last octet (0..7) */
+
+	asn_struct_ctx_t _asn_ctx;	/* Parsing across buffer boundaries */
+} BIT_STRING_t;
+
+extern asn_TYPE_descriptor_t asn_DEF_BIT_STRING;
+extern asn_TYPE_operation_t asn_OP_BIT_STRING;
+extern asn_OCTET_STRING_specifics_t asn_SPC_BIT_STRING_specs;
+
+asn_struct_print_f BIT_STRING_print;	/* Human-readable output */
+asn_struct_compare_f BIT_STRING_compare;
+asn_constr_check_f BIT_STRING_constraint;
+xer_type_encoder_f BIT_STRING_encode_xer;
+oer_type_decoder_f BIT_STRING_decode_oer;
+oer_type_encoder_f BIT_STRING_encode_oer;
+per_type_decoder_f BIT_STRING_decode_uper;
+per_type_encoder_f BIT_STRING_encode_uper;
+asn_random_fill_f  BIT_STRING_random_fill;
+
+#define BIT_STRING_free              OCTET_STRING_free
+#define BIT_STRING_decode_ber        OCTET_STRING_decode_ber
+#define BIT_STRING_encode_der        OCTET_STRING_encode_der
+#define BIT_STRING_decode_xer        OCTET_STRING_decode_xer_binary
+#define BIT_STRING_decode_aper       OCTET_STRING_decode_aper
+#define BIT_STRING_encode_aper       OCTET_STRING_encode_aper
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* _BIT_STRING_H_ */