Re: [PATCH] erase variable data on user unset

[Robert Millan]

On Sun, Feb 10, 2008 at 04:38:37PM -0500, Isaac Dupree wrote:
> on second thought, if grub is going to be able to boot kernels that are 
> on encrypted partitions, the password might go more places in grub 
> and/or have to be retained until boot time, depending how it works...

Not until boot time, just up to the load command.  I guess you mean
something like:

echo -n "Password: "
read password
lvm_somecommand $password
linux (lvm-device)/boot/linux.img
unset password
boot

Here, the lvm module would be responsible for its own copy of the password.  It
does already know that sensitive information is being handled, so when
grub_lvm_fini() is called, it'll erase it.

The other copy is in the environment, so user clears it after loading linux,
because our env handler doesn't know that some variables might contain
sensitive info.

-- 
Robert Millan

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