C# Stream text/data to zip/gpg instead of passing app a filename?

Question

I currently have an app written in C# that can take a file and encrypt it using gpg.exe

What I'm trying to do is, instead of 1. Creating a file (from database queries usually) 2. encrypting the file 3. deleting the non-encrypted file

I want to

1. Gather info into memory (into a dictionary or a list or whatever)
2. stream the text/data into gpg.exe to end up with the encrypted file outputted

I've looked into pipestream, redirecting standard input to the gpg process, etc, but I haven't figured out a way to trick gpg.exe into accepting streamed text/data instead of a file on the hard drive.

Initially figured if I could do it for gpg, I could also do it for Zip as well, but I'm wondering if it's even possible. Found some refs to popen which seems to be php related, but nothing for c#.

Essentially, I'm looking to do the below programatically with text.txt being stuff in memory streamed to the app instead of an actual file on the hard drive.

C:\Program Files\GNU\GnuPG>type C:\test.txt | zip > plubber.zip C:\Program Files\GNU\GnuPG>type C:\test.txt | gpg -er "mycomp_operations [email protected]" > Test.pgp

Thanks for any help you may be able to give :)

Tony!

Answer 1

Well, named-pipes does most of what you are discussing, but to be honest it isn't worth it... in most cases, a temp file is a reasonable approach.

Answer 2

You can use DotNetZip to create a zip file in-memory, but I don't know how that would interface with the gpg stuff. DotNetZip can do AES encryption, but that is obviously a different model from PGP or GPG.

Just a quick googly search turned up
this hint on GPG.

Looks like they run the gpg.exe in a separate process, sitting there waiting for input.

Answer 3

Please review the BouncyCastle C# implementation at:

http://www.bouncycastle.org/csharp/

This will allow GPG inprocess encryption and decryption without external files. I am currently using it to do the same thing for a BizTalk pipeline component.

Answer 4

Using our SecureBlackbox components you can avoid calling external program for ZIP or PGP operations. The components operate with streams and don't need temporary files.