Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752069AbdHCDRN (ORCPT ); Wed, 2 Aug 2017 23:17:13 -0400 Received: from orcrist.hmeau.com ([104.223.48.154]:57918 "EHLO deadmen.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751188AbdHCDRL (ORCPT ); Wed, 2 Aug 2017 23:17:11 -0400 Date: Thu, 3 Aug 2017 11:16:52 +0800 From: Herbert Xu To: Horia =?utf-8?Q?Geant=C4=83?= Cc: Harald Freudenberger , Oleksij Rempel , "linux-kernel@vger.kernel.org" , Oleksij Rempel , Dan Douglass , "linux-crypto@vger.kernel.org" , "kernel@pengutronix.de" , Martin Schwidefsky , "David S. Miller" Subject: Re: [PATCH v1] crypto: caam - set hwrng quality level Message-ID: <20170803031652.GA10515@gondor.apana.org.au> References: <20170719074458.9247-1-o.rempel@pengutronix.de> <20170719163248.sn7mvnq2s3fm2hvh@pengutronix.de> <20170719181303.rj4fyjj7qplatrzk@pengutronix.de> <4e42d639-9f83-dcbb-9a2a-91686656c7dd@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 575 Lines: 15 On Wed, Aug 02, 2017 at 02:03:14PM +0000, Horia Geantă wrote: > > Take CAAM's engine HWRNG: it can work both as a TRNG and as a > TRNG-seeded DRBG (that's how it's currently configured). > IIUC, both setups are fit as source for the entropy pool. So which is it? If it's a DRBG then it should not be exposed through the hwrng interface. Only TRNG should go through hwrng. DRBGs can use the crypto rng API. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt