#ifndef _NTRTL_H
NTSYSAPI
NTSTATUS
NTAPI
RtlGetDaclSecurityDescriptor(
    _In_ PSECURITY_DESCRIPTOR SecurityDescriptor,
    _Out_ PBOOLEAN DaclPresent,
    _Outptr_result_maybenull_ PACL *Dacl,
    _Out_ PBOOLEAN DaclDefaulted
    );
View code on GitHubThis function is documented in Windows Driver Kit.