Re: Back to the future.

Pavel Machek
2007-05-05T09:16:57Z

Hi!

> But the same functionality can be achieved by doing:
>
> 1) Define a user password (e.g. /etc/shadow thing). (Once)
>
> 2) When a user logs in: get random data and encrypt it with the password,
> this becomes the AES key. Store both the data and key in a secure way in
> memory, e.g. using the existing kernel key infrastructure.

> Advantage of this scheme is that it only need AES and can be done (mostly)
> in kernel space. It's also faster and simpler than the current RSA scheme.
> Disadvantage is that it wastes at least 32 bytes of memory when the system
> is running, to store the data and key.

Another disadvantage is that you need to hack into PAM infrastructure,
that your suspend password needs to be same as someone's login
password, and that it will really only work with single-user machine.

Pavel
--
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