[Cryptography] Speeding up Linux disk encryption

[Theodore Ts'o]

On Mon, Apr 12, 2021 at 04:22:18PM -0400, Jerry Leichter wrote:
> The big cloud storage providers put a lot of work into this.  I've
> seen specific discussions of this concerning Google, for example.
> Each individual drive is tracked from "birth" to death.  No drive,
> once it's been actually accessed on a live system, ever leaves the
> building without being physically destroyed.  There are all kinds of
> procedures for drive handling to make sure this can never happen.
> 
> All of this even though most of the user data written to drives is
> encrypted anyway.
> 
> A "lost" drive would be a major, major crisis.
> 
> Physical security and proper handling of valuable physical objects
> is something we've been doing for a long, long time.
> 
> Of course any process can fail or be deliberately *made* to fail -
> even bank vaults get broken into - but I would rank that risk pretty
> low for users of any major vendor.

In *addition* to full disk encryption, product-level and user-level
encryption, additional layers of security include metal detectors to
make sure hard drives and servers can't get removed without being
noticed, and "man traps" to prevent tail gating (only one person can
enter or exit per badge scan).

      https://www.youtube.com/watch?v=kd33UVZhnAA
      https://services.google.com/fh/files/misc/google_security_wp.pdf

Why so many layers?  Because goal is to prevent not just accidental
data exfiltration, but exfiltration by malicious actors who are
*trying* to bypass all of the security layers.  In addition, cloud
providers need to keep customers (and their auditors / compliance
certifiers) comfortable that their data is secure --- which is why the
video and the security white paper exists.

	    	       	      - Ted