Re: [PATCH] security/keys: make BIG_KEYS dependent on stdrng.

[Artem Savkov]

On Tue, Sep 06, 2016 at 02:11:56PM +0100, David Howells wrote:
> Artem Savkov <asavkov@xxxxxxxxxx> wrote:
> 
> > > > -	select CRYPTO
> > > > +	depends on (CRYPTO_ANSI_CPRNG = y || CRYPTO_DRBG = y)
> > > 
> > > Should those be "==" not "="?
> > 
> > Accodring to Documentation/kbuild/kconfig-language.txt (line 173) it is
> > "=" and I can only see "=" being used in existing Kconfigs.
> 
> Okay.  The other thing is that I have been given a conflicting patch (see
> below).  Is your fix preferable?
> 
> David
> ---
> commit 69ed34b303f87a1a53470dd37149ac1573d79da2
> Author: Kirill Marinushkin <k.marinushkin@xxxxxxxxx>
> Date: Mon, 8 Aug 2016 23:19:32 +0200
> 
> KEYS: fix big_key dependency
> 
> Signed-off-by: Kirill Marinushkin <k.marinushkin@xxxxxxxxx>
> cc: David Howells <dhowells@xxxxxxxxxx>
> cc: Peter Hlavaty <zer0mem@xxxxxxxxx>
> cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
> cc: stable@xxxxxxxxxxxxxxx
> ---
>  security/keys/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/security/keys/Kconfig b/security/keys/Kconfig
> index f826e87..8213221 100644
> --- a/security/keys/Kconfig
> +++ b/security/keys/Kconfig
> @@ -44,7 +44,7 @@ config BIG_KEYS
>  	select CRYPTO
>  	select CRYPTO_AES
>  	select CRYPTO_ECB
> -	select CRYPTO_RNG
> +	select CRYPTO_ANSI_CPRNG
>  	help
>  	  This option provides support for holding large keys within the kernel
>  	  (for example Kerberos ticket caches).  The data may be stored out to

I would argue that locking a user into a specific stdrng implementation
is not something that should be done when there are options available.

-- 
Regards,
  Artem