typedef struct _KALPC_SECURITY_DATA
{
    ALPC_HANDLE_TABLE *HandleTable;
    void *ContextHandle;
    EPROCESS *OwningProcess;
    ALPC_PORT *OwnerPort;
    SECURITY_CLIENT_CONTEXT DynamicSecurity;
    union
    {
        struct
        {
            unsigned long Revoked : 1;
            unsigned long Impersonated : 1;
        } s1;
    } u1;
} KALPC_SECURITY_DATA, *PKALPC_SECURITY_DATA;