unsigned hex_to_base64(const char* hex_buff, char*& base64_buff, unsigned hex_buff_len );
void convert_string_to_hex(const char* const iArray, const unsigned iArrayLen, unsigned char*& oHexArray);
void convert_hex_to_string(const unsigned char* const iHexArray, unsigned iHexArrayLen, char*& oStringBuf );
void xor_strings(const char* const iLeftString, const char* const iRightString, unsigned char*& oXorArray);