--- /dev/null
+/*-
+ * Copyright (c) 2003-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#ifndef _UTF8String_H_
+#define _UTF8String_H_
+
+#include <OCTET_STRING.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef OCTET_STRING_t UTF8String_t; /* Implemented via OCTET STRING */
+
+extern asn_TYPE_descriptor_t asn_DEF_UTF8String;
+extern asn_TYPE_operation_t asn_OP_UTF8String;
+
+asn_struct_print_f UTF8String_print;
+asn_constr_check_f UTF8String_constraint;
+asn_random_fill_f UTF8String_random_fill;
+
+#define UTF8String_free OCTET_STRING_free
+#define UTF8String_compare OCTET_STRING_compare
+#define UTF8String_constraint UTF8String_constraint
+#define UTF8String_decode_ber OCTET_STRING_decode_ber
+#define UTF8String_encode_der OCTET_STRING_encode_der
+#define UTF8String_decode_xer OCTET_STRING_decode_xer_utf8
+#define UTF8String_encode_xer OCTET_STRING_encode_xer_utf8
+#define UTF8String_decode_uper OCTET_STRING_decode_uper
+#define UTF8String_encode_uper OCTET_STRING_encode_uper
+#define UTF8String_decode_aper OCTET_STRING_decode_aper
+#define UTF8String_encode_aper OCTET_STRING_encode_aper
+
+/*
+ * Returns length of the given UTF-8 string in characters,
+ * or a negative error code:
+ * -1: UTF-8 sequence truncated
+ * -2: Illegal UTF-8 sequence start
+ * -3: Continuation expectation failed
+ * -4: Not minimal length encoding
+ * -5: Invalid arguments
+ */
+ssize_t UTF8String_length(const UTF8String_t *st);
+
+/*
+ * Convert the UTF-8 string into a sequence of wide characters.
+ * Returns the number of characters necessary.
+ * Returned value might be greater than dstlen.
+ * In case of conversion error, 0 is returned.
+ *
+ * If st points to a valid UTF-8 string, calling
+ * UTF8String_to_wcs(st, 0, 0);
+ * is equivalent to
+ * UTF8String_length(const UTF8String_t *st);
+ */
+size_t UTF8String_to_wcs(const UTF8String_t *st, uint32_t *dst, size_t dstlen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _UTF8String_H_ */