I was not asked to keep this off list but removing attribution just in
case.

>
> On Thu, May 30, 2013 at 8:49 PM, shawn wilson <[email protected]> wrote:
> > Thanks for all of the input. In the end I think I'm going to go with
> > the simplest solution (along the way, I found ima-linux and signelf).
> >
> > Let me know if what issues there are with this:
> > Encrypt the LUKS passkey in a text file.
> > Encrypt a user defined message and file checksums in another file with
> > a different password. Decrypt this file first and display the message
> > (letting the user know that if it doesn't look right, they should
> > stop). Get the hashes of all of the files and compare them with the
> > data in the text file and report if anything didn't match. If all is
> > good, prompt for the password of the second file.
> If the evil maid installs herself in the BIOS or a periphery's ROM,
> then there's not a lot you can do. The user's password will always be
> exposed. You could even boot to a thumb drive, perform the integrity
> check, and things would still look fine from the outside.
>

If the hardware is altered in an undetectable manner, you're right. But is
the boot image is altered (ROM or otherwise) the checksum process would
fail. I could even have a simple pass/fail test case to show the user that
diff or comm were not altered.

Also, I think there is kernel support for reading most BIOS models. So
maybe next, I should look into that. Though, I think at the point of
altering hardware is where I need to call it quits - someone could modify
any PCI card and as long as it was loaded at that point, there will be at
least some leakage and I can't verify everything. Either way, I'll see how
far I can get with dumping hardware data and hashing it as well.
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