linux-kernel - Re: [PATCH] random: add random_initialized command line param

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: <20150520150642.GJ2871@thunk.org>
Date:	Wed, 20 May 2015 11:06:42 -0400
From:	Theodore Ts'o <tytso@....edu>
To:	Stephan Mueller <smueller@...onox.de>
Cc:	Sandy Harris <sandyinchina@...il.com>,
	Herbert Xu <herbert@...dor.apana.org.au>,
	linux-crypto@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] random: add random_initialized command line param

On Wed, May 20, 2015 at 08:29:19AM +0200, Stephan Mueller wrote:
> 
> But I see that such a change may not be warranted at this
> point. Though, I see that discussion may rise again in the future
> when such new requirements for 256 bit keys (not only AES, thanks
> Sandy for mentioning :-) ) are commonly raised.

Given that you would need a 15,360-bit RSA key to have a key strength
equivalent to a 256-bit key (and a 3072-bit RSA key is equivalent to
128-bit symmetric keys, and there are plenty of people still using
2048-bit keys), permit me to be a little skeptical about the value of
256 bit keys for anything other than marketing value...

If you trust ECC, you'd "only" need a 7,680 bit ECC key.  But the ECC
curves under discussion today are (at least) an order of magnitude
smaller.

And if it's just to make gullible rubes feel safer, I don't see the
real point of non-blocking random pool threshold larger than the
safety of the whole system is constrainted by public key crypto.

> So, let us disregard the patch until hard requirements are coming up.

Sounds like a fine idea to me.

              				- Ted
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/