linux-kernel - Re: [PATCH v7] lib/crypto: blake2s: include as built-in

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YdYXEBhc7vuY+GQW@gmail.com>
Date:   Wed, 5 Jan 2022 14:09:20 -0800
From:   Eric Biggers <ebiggers@...nel.org>
To:     Ard Biesheuvel <ardb@...nel.org>
Cc:     Herbert Xu <herbert@...dor.apana.org.au>,
        "Jason A. Donenfeld" <Jason@...c4.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Masahiro Yamada <masahiroy@...nel.org>,
        Linux Kbuild mailing list <linux-kbuild@...r.kernel.org>,
        Linux Crypto Mailing List <linux-crypto@...r.kernel.org>
Subject: Re: [PATCH v7] lib/crypto: blake2s: include as built-in

On Wed, Jan 05, 2022 at 11:01:04PM +0100, Ard Biesheuvel wrote:
> On Wed, 5 Jan 2022 at 22:53, Eric Biggers <ebiggers@...nel.org> wrote:
> >
> > On Tue, Jan 04, 2022 at 06:02:52PM +0100, Ard Biesheuvel wrote:
> > > The only downside here is that the ARM/x86 accelerated shashes and the
> > > generic shash now use the same core transform, right?
> >
> > I don't see how this is the case, given that crypto/blake2s_generic.c still uses
> > blake2s_compress_generic(), not blake2s_compress().
> >
> 
> Ah ok, I stand corrected then.
> 
> So what are your thoughts on this? Should we keep the shashes while
> they have no users?

I don't know.  Removing unused stuff is good per se, but I wouldn't have
expected this to be something that is being considered here.  It's not like this
is a "controversial" algorithm, blake2b is already supported, and there could be
users of it already (dm-integrity, dm-verity, AF_ALG, etc.).  If this is going
to happen, then the acceptance criteria for new algorithms need to get *much*
stricter, so that algorithms aren't constantly being added and removed.

- Eric