Re: [PATCH] crypto: don't raise alarm for no ctr(aes*) tests in fips mode

From: Jarod Wilson
Date: Mon May 04 2009 - 14:57:58 EST


On Monday 04 May 2009 07:10:10 Herbert Xu wrote:
> On Tue, Apr 28, 2009 at 09:18:22PM -0400, Jarod Wilson wrote:
> > Per the NIST AESAVS document, Appendix A[1], it isn't possible to
> > have automated self-tests for counter-mode AES, but people are
> > misled to believe something is wrong by the message that says there
> > is no test for ctr(aes). Simply suppress all 'no test for ctr(aes*'
> > messages if fips_enabled is set to avoid confusion.
>
> This is not true at all. In our implementation the counter is
> set through the IV so it definitely is possible to test counter
> mode algorithms in Linux.

Ah... Now I think I see... We can provide an initial counter w/o a
problem, but counter incrementation is implementation-specific, so
we can't have automated tests that cover multiple enc/dec ops, but
if we limit ourselves to just one op, self-tests should be perfectly
doable, and NIST SP 800-38A, Appendix F.5 has vectors we could make
use of (using just the block #1 values). At least, spot-checking
the vectors, I'm getting the expected results for the 1st block.

Okay, I'll whip something up in a sec.

--
Jarod Wilson
jarod@xxxxxxxxxx
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