Re: [PATCH v7 0/6] SP800-90A Deterministic Random Bit Generator

Am Freitag, 30. Mai 2014, 17:05:48 schrieb Herbert Xu:

Hi Herbert,

On Mon, May 26, 2014 at 07:42:57AM +0200, Stephan Mueller wrote:

quoted

A second aspect is the implementation of the stdrng. Currently, the
offered
patch does not include the stdrng selection. I am currently working on the
completion of the addition of the stdrng selection to the offered patch.
My
idea is the following: currently, all DRBG types are registered with their
own cra_name. However, there shall be one particular DRBG registered
twice. When registering the instance again, the cra_name shall be
"stdrng". In addition, if the kernel command line contains fips=1, the
cra_priority of that stdrng should be set to 300. That implies that when
the kernel resolves the stdrng, it resolves to get_random_bytes in normal
mode, but to the stdrng DRBG in FIPS mode.

Just have all of them register as stdrng with differing priorities.

Will do. Just to clarify: I would use priorities below 200 if (!fips_enabled) 
and above 200 for fips_enabled. This would mean that per default, the 
get_random_bytes/krng has the highest priority in non-fips mode. In FIPS mode, 
the DRBGs would have the higher priority per default.

We already have a user-space interface to change priorities.

Great -- if I may ask, which interface is that?

Cheers,

Ciao
Stephan
-- 
| Cui bono? |