Re: [PATCH] crypto: lib/arc4 - expose library interface

[Christian Marangi]

On Fri, Jul 15, 2022 at 07:39:48AM +0000, David Laight wrote:
> From: Eric Biggers
> > Sent: 15 July 2022 03:05
> > 
> > On Thu, Jul 14, 2022 at 07:12:21AM +0200, Christian Marangi wrote:
> > > Permit to compile the arc4 crypto lib without any user. This is required
> > > by the backports project [1] that require this lib for any wireless
> > > driver.
> > >
> > > [1] https://backports.wiki.kernel.org/index.php/Main_Page
> > >
> > > Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
> > > ---
> > >  lib/crypto/Kconfig | 6 +++++-
> > >  1 file changed, 5 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig
> > > index 2082af43d51f..2dfc785a7817 100644
> > > --- a/lib/crypto/Kconfig
> > > +++ b/lib/crypto/Kconfig
> > > @@ -6,7 +6,11 @@ config CRYPTO_LIB_AES
> > >  	tristate
> > >
> > >  config CRYPTO_LIB_ARC4
> > > -	tristate
> > > +	tristate "ARC4 library interface"
> > > +	help
> > > +	  Enable the ARC4 library interface. This interface is mainly
> > > +	  used by wireless drivers and is required by the backports
> > > +	  project.
> > >
> > >  config CRYPTO_ARCH_HAVE_LIB_BLAKE2S
> > >  	bool
> > 
> > I don't think this is appropriate for upstream, as the upstream kernel doesn't
> > support out-of-tree code.  This is also an internal API that can change from one
> > kernel version to the next.
> 
> Out-of-tree code always has to allow for arbitrary changes to
> kernel interfaces between kernel versions.
> So the fact that the API might change isn't relevant.
> The continual API changes keep some of us in a job :-)
> 
> (It has to be said that if I needed RC4 I'd probably add a local copy.)
>

Wonder if I can ask you some advice about the topic... I understand that
this cannot be merged upstream.

So the correct solution would be having a copy of the arc4 lib in
backports?

-- 
	Ansuel