linux-kernel - Re: [PATCH v2 8/9] random: use hash function for crng_slow

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: <YhMJoYykeNTVpz7w@sol.localdomain>
Date:   Sun, 20 Feb 2022 19:40:17 -0800
From:   Eric Biggers <ebiggers@...nel.org>
To:     "Jason A. Donenfeld" <Jason@...c4.com>
Cc:     linux-crypto@...r.kernel.org, linux-kernel@...r.kernel.org,
        tytso@....edu, linux@...inikbrodowski.net
Subject: Re: [PATCH v2 8/9] random: use hash function for crng_slow_load()

On Wed, Feb 09, 2022 at 02:19:18AM +0100, Jason A. Donenfeld wrote:
> Since we have a hash function that's really fast, and the goal of
> crng_slow_load() is reportedly to "touch all of the crng's state", we
> can just hash the old state together with the new state and call it a
> day. This way we dont need to reason about another LFSR or worry about
> various attacks there. This code is only ever used at early boot and
> then never again.
> 
> Cc: Theodore Ts'o <tytso@....edu>
> Cc: Dominik Brodowski <linux@...inikbrodowski.net>
> Signed-off-by: Jason A. Donenfeld <Jason@...c4.com>
> ---
>  drivers/char/random.c | 42 +++++++++++++++---------------------------
>  1 file changed, 15 insertions(+), 27 deletions(-)

Reviewed-by: Eric Biggers <ebiggers@...gle.com>

- Eric