Re: Support three application types for my encryptionminifilter.

Hi,

I’m thinking to implement such mechanism with minifilter (encrypted file , only single process can see the decrypted contents the file) ,
But you says that if the file is accessed using memory-mapped file , there’s no way to implement such mechanism (except writing FSD and not filter/minifilter) ,
My question is - can Minifilter change the SectionObjectPointer (create it’s own for the permitted application) ? How about creating an “associated mapping” (another file-object) to achieve this task … ?

tnx

On Tue 27 Feb 17:20 2007 Dejan Maksimovic wrote:

Mm, right :wink: That should’ve read no way in a filter.

Ladislav Zezula wrote:

> > To answer OP’s question: There is no way (at least not any the public here is
> > aware of and can share) to provide encrypted contents to an application using memory
> > mapped I/O if you provide cleartext to any other application that uses memory mapped
> > I/O.
>
> … unless you create a layered file system, which manages two system caches for each
> encrypted file. One containing encrypted text and one containing plaintext. On
> IRP_MJ_CREATE request, you just choose the proper SectionObjectPointer
> and put it to the file object.


Kind regards, Dejan
http://www.alfasp.com
File system audit, security and encryption kits.


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