linux-kernel - Re: [PATCH 5/7] random: replace non-blocking pool with a Chacha20-based CRNG

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]

Date:	Mon, 20 Jun 2016 09:25:28 +0800
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	Theodore Ts'o <tytso@....edu>,
	Linux Kernel Developers List <linux-kernel@...r.kernel.org>,
	linux-crypto@...r.kernel.org, smueller@...onox.de,
	andi@...stfloor.org, sandyinchina@...il.com, jsd@...n.com,
	hpa@...or.com
Subject: Re: [PATCH 5/7] random: replace non-blocking pool with a
 Chacha20-based CRNG

On Sun, Jun 19, 2016 at 07:18:28PM -0400, Theodore Ts'o wrote:
>
> C) Simply compiling in the Crypto layer and the ChaCha20 generic
> handling (all of which is doing extra work which we would then be
> undoing in the random layer --- and I haven't included the extra code
> in the random driver needed interface with the crypto layer) costs an
> extra 20k.  That's roughly the amount of extra kernel bloat that the
> Linux kernel grew in its allnoconfig from version to version from 3.0
> to 3.16.  I don't have the numbers from the more recent kernels, but
> roughly speaking, we would be responsible for **all** of the extra
> kernel bloat (and if there was any extra kernel bloat, we would
> helping to double it) in the kernel release where this code would go
> in.  I suspect the folks involved with the kernel tinificaiton efforts
> wouldn't exactly be pleased with this.
> 
> Yes, I understand the argument that the networking stack is now
> requiring the crypto layer --- but not all IOT devices may necessarily
> require the IP stack (they might be using some alternate wireless
> communications stack) and I'd much rather not make things worse.

Sure, but 99% of the kernels out there will have a crypto API.
So why not use it if it's there and use the standalone chacha
code otherwise?

Cheers,
-- 
Email: Herbert Xu <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt