Ramdisk encryption

Ramdisk encryption

[Lei Yang]

Hello,

Can I set up a ramdisk and use loopback encryption to encrypt it?
As far as I understand, the OS will keep data encrypted on the hard 
disk at all times and decrypts it in RAM only as it's read. So an encrypted 
executable on physical hard disk will be decrypted page by page upon
reading to RAM. But what happens to an executable sitting in ramdisk?
Can I also encrypt it? Since the code is in RAM, it should be running in place,
how do kernel deal with encrypted code and run? 

Any comments?

Thanks in advance!
Lei

Re: Ramdisk encryption

[Andreas Jellinghaus]

you are looking for disk encryption.
take a look at dm-crypt. the kernel
will read the encrypted partition, decrypt,
run the software, and if you write data,
before writing it, the kernel will encrypt
it.

you don't need a ramdisk for that.

Andreas

RE: Ramdisk encryption

[Andreas Jellinghaus]

I never tried it, but I see no reason, why dm-crypt shouldn't work
on top of a ramdisk too. If you have any trouble with it, there
is a dm-crypt mailing list, and the author is very responsive.

Andreas

RE: Ramdisk encryption

[Lei Yang]

Thanks a lot! I'll try and let you know the result.
I also think it should work on ramdisk, just want to know how it really works internally to help better understand. Any recommended readings or materials?

Lei

-----Original Message-----
From: Andreas Jellinghaus [mailto:aj@dungeon.inka.de]
Sent: Monday, July 19, 2004 4:44 PM
To: Lei Yang
Cc: linux-kernel@vger.kernel.org
Subject: RE: Ramdisk encryption


I never tried it, but I see no reason, why dm-crypt shouldn't work
on top of a ramdisk too. If you have any trouble with it, there
is a dm-crypt mailing list, and the author is very responsive.

Andreas