Browse Prior Art Database

Transparent Dynamic Link Library Interface

IP.com Disclosure Number: IPCOM000104855D
Original Publication Date: 1993-Jun-01
Included in the Prior Art Database: 2005-Mar-19
Document File: 2 page(s) / 49K

Publishing Venue

IBM

Related People

Lennon, CJ: AUTHOR [+4]

Abstract

Disclosed is a methodology by which a proprietary program interface can be hidden from a user so that analysis of a program's logic flow can be prevented.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 67% of the total text.

Transparent Dynamic Link Library Interface

      Disclosed is a methodology by which a proprietary program
interface can be hidden from a user so that analysis of a program's
logic flow can be prevented.

      Currently, programs written for OS/2* are compiled and then
link edited into Dynamic Link Libraries (DLLs).  These DLLs are
called by other programs to provide services such as database
input/output operations and network communications.  Availability of
these interfaces to a user for the purpose of determining logic flow
of these DLLs is quite easy.  The Transparent Dynamic Link Library
Interface (TDLLI) is a methodology by which an application can access
system services through a common router component which loads the DLL
that is to process the request and forwards the request through OS/2
Presentation Manager* (PM), thus providing a mask to the actual DLL
interface.

      When an application requires a service of a DLL that is to be
protected, the application calls the TDLLI router which loads the DLL
that is to process the request and then uses OS/2 Presentation
Manager to forward the request.  The TDLLI router packages the
request and utilizes the WinSendMessage facility of Presentation
Manager to transport the request to the target DLL.

      When the TDLLI receives a request, it selects the proper DLL to
process the request through a directory which contains the supported
request types which are mapped to DLL names for loading.  Each DL...