Re: [PATCH] crypto: mark cts(cbc(aes)) as FIPS allowed

[Gilad Ben-Yossef]

Hi Stephan,

On Mon, Nov 5, 2018 at 10:50 AM Stephan Mueller <smueller@xxxxxxxxxx> wrote:
>
> Am Sonntag, 4. November 2018, 11:05:24 CET schrieb Gilad Ben-Yossef:
>
> Hi Gilad,
>
> > As per Sp800-38A addendum from Oct 2010[1], cts(cbc(aes)) is
> > allowed as a FIPS mode algorithm. Mark it as such.
> >
> > [1] https://csrc.nist.gov/publications/detail/sp/800-38a/addendum/final
>
> There are several types of CTS approaches. Only three of those are listed in
> the SP800-38A addendum. The source code only refers to some RFCs.
>
> Did you check whether the CTS implementation matches one or more of the types
> listed in the addendum? If yes, may I suggest to add a small statement in the
> code noting this fact?

Yes, AFAIK the software implements CBC-CS3 as described in the document.
You have a very good point about this not document anywhere. I will
send a patch.

While we're at it, does someone find it useful if I implemented the
other two modes?
They are part of the standard as well, although I am not sure that in
itself is sufficient cause.


Gilad

--
Gilad Ben-Yossef
Chief Coffee Drinker

values of Î will give rise to dom!