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Digital signature on VBA projects

Hi,

I was wondering if there is some news on the Digital signature issue for VBA projects.

Regards,

Richard Bergmans
Ingenieursbureau van der Linden
The Netherlands

Sorry no progress on this one yet. We cannot figure out things for certain ourselves and still waiting for documentation from MS.

Hi Roman,

Also wondering if there is any progress on this issue ?

With regards,

Richard Bergmans

Hi Richard,

We are still waiting (optimisitic) for the doc.

Hi Roman,

Still waiting for the doc ?


With regards,

Richard Bergmans
Ingenieursbureau van der Linden
The Netherlands

Hi Richard,

Sorry, not good news on this one. It seems we cannot get the format documentaiton the way we want it, so I think ability to preserve digital signatures is postponed indefinitely (until we find a hacker willing to work on them).

I don't think it's easy. Just think what a digital signature is for - to prevent unathorized modifications to the document. So in theory, it should not be possible to attach the same digital signature to the modified document unless you have the private key. The only hope I have here is that the digital signature does not apply to the whole document, but only to the VBA code that we do not change.

By the way, do you think you would be interested in implementing this feature yourself?

Hi Roman,

I was afraid there would be a problem with the documentation because it involves a security issue. But that same security issue is what we would like to preserve so our customers know that the documents generated within our application has a digital signature from us. And therefore can trust the documents with its vba code from our application.

I sure am interested in implementing this feature, but my knowledge about the MS Word document format in technical isn’t much. But I’m willing to try if possible.

With regards,

Richard Bergmans
Ingenieursbureau van der Linden
The Netherlands.

Please talk to me about this more using one of the live support options http://www.aspose.com/Corporate/Teams/Product/Auckland/Contactus.html

Hi Roman,

This will be another time I am afraid. Can you tell me what timezone you are in, country ?

I will contact you next week I think using one of the live support options.
For now I am going to sleep, I have to get up early tomorrow.

With regards,

Richard Bergmans

My timezone is New Zealand, GMT+12.

You don’t need to deal a lot with Word file format because VBA and digital signatures are not documented in it anyway.

DOC files are compound files in structured storage format. DFVIEW.EXE from Visual Studio 6.0 can read and display storages and streams (folders and files) inside such files.

I can provide portions of Aspose.Word source code that allow to read and write structured storage files and give you basic info that I know about how VBA is stored inside the file.

All you need to do is apply some creativity in actually finding where and how the digital signature is stored. Then a little experiment to modify just a character inside the text and see if the digital signature for the VBA code still holds (maybe this should be done beforhand).

Hi Roman,

I didn’t know if I had given my email to you. I also searched in the MSDN subscriptions for the DFView utility but couldn’t find it. So if you could mail me the utility also it would be great. I can’t find it in my Visual Studio .NET 2003 installation.

You send it all to richard.bergmans@iblinden.nl

Regards,

Richard Bergmans

Digital signature on VBA projects is fully preserved in Aspose.Word 2.1.1, for more info see http://aspose.com/blogs/Roman.Korchagin/archive/2005/01/05/379.aspx