linux-kernel - Re: [PATCH v2 04/10] crypto/compress: add asynchronous compression support

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:	Wed, 27 Jan 2016 15:41:40 +0800
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	Joonsoo Kim <js1304@...il.com>
Cc:	"David S. Miller" <davem@...emloft.net>,
	Weigang Li <weigang.li@...el.com>,
	Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>,
	Minchan Kim <minchan@...nel.org>,
	Dan Streetman <ddstreet@...e.org>,
	linux-crypto@...r.kernel.org, linux-kernel@...r.kernel.org,
	Joonsoo Kim <iamjoonsoo.kim@....com>
Subject: Re: [PATCH v2 04/10] crypto/compress: add asynchronous compression
 support

On Tue, Jan 26, 2016 at 05:15:06PM +0900, Joonsoo Kim wrote:
> From: Weigang Li <weigang.li@...el.com>
> 
> Now, asynchronous compression APIs are supported. There is no asynchronous
> compression driver now but this APIs can be used as front-end to
> synchronous compression algorithm. In this case, scatterlist would be
> linearlized when needed so it would cause some overhead.
> 
> Signed-off-by: Weigang Li <weigang.li@...el.com>
> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@....com>

I think we should be able to use this for the synchronous case
too, like we do with skcipher and ahash.

The main difference that I can see right now is that acomp always
allocates a context through the request object while scomp does not.

This difference is entirely artificial as we could also make the
context conditional for acomp.

The reason we had the shash/ahash division is because the shash
interface offers a direct pointer interface while ahash is SG-based.
Otherwise ahash is just as able as shash to handle synchronous
requests.

At this point in time I don't see such a fundamental distinction
between acomp and scomp.

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