Prevent other programmers from using my dll component?

[kjon]

Hi, I've developed a couple of DLL assemblies component to be used with my
main exe application.

Since I need to distribute all the exe and dlls to the user PC, how can I
prevent the user, who might happen to have programming knowledge, from using
the dlls in their own application?

I know this may sound a bit paranoid, but I believe there must be some way
to prevent this. May be I should compile the dlls into the single exe or tie
the dlls to the main exe or something....??

Please advice. Thanks.

[Jon Skeet [C# MVP]]

Re: Prevent other programmers from using my dll component?

kjon <2@22.co> wrote:[color=blue]
> Hi, I've developed a couple of DLL assemblies component to be used with my
> main exe application.
>
> Since I need to distribute all the exe and dlls to the user PC, how can I
> prevent the user, who might happen to have programming knowledge, from using
> the dlls in their own application?
>
> I know this may sound a bit paranoid, but I believe there must be some way
> to prevent this. May be I should compile the dlls into the single exe or tie
> the dlls to the main exe or something....??[/color]

I don't know exactly how .NET obfuscators work, never having used one,
but you may be able to obfuscate your exe and dll at the same time, so
that name changes in the dll are reflected in the exe. That doesn't
stop anyone from using the dll, but it makes it almost impossible to
understand what's used for what.

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[Leon Lambert]

Re: Prevent other programmers from using my dll component?

Welcome to the complex world of CAS (Code access Security). You can key
the libraries so they can only be used by your applications. Use this
link in your Visual studio help to start diving into the topic
ms-help://MS.VSCC.2003/MS.MSDNQTR.2004 APR.1033/cpguide/html/cpconCodeAccess Security.htm

This is an extreemly complicated subject with many options. We are in
the process of trying to get Microsoft to give us better documentation
on these issues ourself. .Net does have a lot of support but how and
where to use it are not well documented.

Hope this helps to get you started.
Leon Lambert

kjon wrote:[color=blue]
> Hi, I've developed a couple of DLL assemblies component to be used with my
> main exe application.
>
> Since I need to distribute all the exe and dlls to the user PC, how can I
> prevent the user, who might happen to have programming knowledge, from using
> the dlls in their own application?
>
> I know this may sound a bit paranoid, but I believe there must be some way
> to prevent this. May be I should compile the dlls into the single exe or tie
> the dlls to the main exe or something....??
>
> Please advice. Thanks.
>
>[/color]

[Sijin Joseph]

Re: Prevent other programmers from using my dll component?

You need to give a StrongName to your main exe and in your DLL's ensure
that all callers have a StrongNameIdent ityPermission of the main exe's
strong name.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemsecuritypermissionsstrongnameidentitypermissionclasstopic.asp

Sijin Joseph

http://www.indiangeek.net

http://weblogs.asp.net/sjoseph

kjon wrote:[color=blue]
> Hi, I've developed a couple of DLL assemblies component to be used with my
> main exe application.
>
> Since I need to distribute all the exe and dlls to the user PC, how can I
> prevent the user, who might happen to have programming knowledge, from using
> the dlls in their own application?
>
> I know this may sound a bit paranoid, but I believe there must be some way
> to prevent this. May be I should compile the dlls into the single exe or tie
> the dlls to the main exe or something....??
>
> Please advice. Thanks.
>
>[/color]