diff --git a/include/osmocom/rspro/OCTET_STRING.h b/include/osmocom/rspro/OCTET_STRING.h
new file mode 100644
index 0000000..bc25666
--- /dev/null
+++ b/include/osmocom/rspro/OCTET_STRING.h
@@ -0,0 +1,88 @@
+/*-
+ * Copyright (c) 2003 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#ifndef	_OCTET_STRING_H_
+#define	_OCTET_STRING_H_
+
+#include <asn_application.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct OCTET_STRING {
+	uint8_t *buf;	/* Buffer with consecutive OCTET_STRING bits */
+	int size;	/* Size of the buffer */
+
+	asn_struct_ctx_t _asn_ctx;	/* Parsing across buffer boundaries */
+} OCTET_STRING_t;
+
+extern asn_TYPE_descriptor_t asn_DEF_OCTET_STRING;
+
+asn_struct_free_f OCTET_STRING_free;
+asn_struct_print_f OCTET_STRING_print;
+asn_struct_print_f OCTET_STRING_print_utf8;
+ber_type_decoder_f OCTET_STRING_decode_ber;
+der_type_encoder_f OCTET_STRING_encode_der;
+xer_type_decoder_f OCTET_STRING_decode_xer_hex;		/* Hexadecimal */
+xer_type_decoder_f OCTET_STRING_decode_xer_binary;	/* 01010111010 */
+xer_type_decoder_f OCTET_STRING_decode_xer_utf8;	/* ASCII/UTF-8 */
+xer_type_encoder_f OCTET_STRING_encode_xer;
+xer_type_encoder_f OCTET_STRING_encode_xer_utf8;
+per_type_decoder_f OCTET_STRING_decode_uper;
+per_type_encoder_f OCTET_STRING_encode_uper;
+per_type_decoder_f OCTET_STRING_decode_aper;
+per_type_encoder_f OCTET_STRING_encode_aper;
+
+/******************************
+ * Handy conversion routines. *
+ ******************************/
+
+/*
+ * This function clears the previous value of the OCTET STRING (if any)
+ * and then allocates a new memory with the specified content (str/size).
+ * If size = -1, the size of the original string will be determined
+ * using strlen(str).
+ * If str equals to NULL, the function will silently clear the
+ * current contents of the OCTET STRING.
+ * Returns 0 if it was possible to perform operation, -1 otherwise.
+ */
+int OCTET_STRING_fromBuf(OCTET_STRING_t *s, const char *str, int size);
+
+/* Handy conversion from the C string into the OCTET STRING. */
+#define	OCTET_STRING_fromString(s, str)	OCTET_STRING_fromBuf(s, str, -1)
+
+/*
+ * Allocate and fill the new OCTET STRING and return a pointer to the newly
+ * allocated object. NULL is permitted in str: the function will just allocate
+ * empty OCTET STRING.
+ */
+OCTET_STRING_t *OCTET_STRING_new_fromBuf(asn_TYPE_descriptor_t *td,
+	const char *str, int size);
+
+/****************************
+ * Internally useful stuff. *
+ ****************************/
+
+typedef const struct asn_OCTET_STRING_specifics_s {
+	/*
+	 * Target structure description.
+	 */
+	int struct_size;	/* Size of the structure */
+	int ctx_offset;		/* Offset of the asn_struct_ctx_t member */
+
+	enum asn_OS_Subvariant {
+		ASN_OSUBV_ANY,	/* The open type (ANY) */
+		ASN_OSUBV_BIT,	/* BIT STRING */
+		ASN_OSUBV_STR,	/* String types, not {BMP,Universal}String  */
+		ASN_OSUBV_U16,	/* 16-bit character (BMPString) */
+		ASN_OSUBV_U32	/* 32-bit character (UniversalString) */
+	} subvariant;
+} asn_OCTET_STRING_specifics_t;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* _OCTET_STRING_H_ */