From: Florian Weimer <fw@deneb.enyo.de>
To: Daniel Borkmann <dborkman@redhat.com>
Cc: gregkh@linuxfoundation.org, akpm@linux-foundation.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] lib: memcmp_nta: add timing-attack secure memcmp
Date: Mon, 11 Feb 2013 20:00:54 +0100 [thread overview]
Message-ID: <87zjzallp5.fsf@mid.deneb.enyo.de> (raw)
In-Reply-To: <e73de7873eadcd7a1922535359c46caf25cbf0a2.1360528614.git.dborkman@redhat.com> (Daniel Borkmann's message of "Sun, 10 Feb 2013 23:00:07 +0100")
* Daniel Borkmann:
> + * memcmp_nta - memcmp that is secure against timing attacks
It's not providing an ordering, so it should not have "cmp" in the
name.
> + for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
> + res |= (*su1 ^ *su2);
The compiler could still short-circuit this loop. Unlikely at
present, but this looks like a maintenance hazard.
next prev parent reply other threads:[~2013-02-11 19:18 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1360528614.git.dborkman@redhat.com>
2013-02-10 22:00 ` [PATCH] lib: memcmp_nta: add timing-attack secure memcmp Daniel Borkmann
2013-02-10 23:24 ` Joe Perches
2013-02-10 23:30 ` Daniel Borkmann
2013-02-10 23:50 ` Greg KH
2013-02-11 8:19 ` Daniel Borkmann
2013-02-11 18:37 ` Andy Lutomirski
2013-02-11 19:39 ` Daniel Borkmann
2013-02-11 19:00 ` Florian Weimer [this message]
2013-02-11 22:58 ` Daniel Borkmann
2013-02-12 10:23 ` Florian Weimer
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