From mboxrd@z Thu Jan 1 00:00:00 1970 From: clabbe.montjoie@gmail.com (Corentin Labbe) Date: Thu, 23 Mar 2017 09:23:07 +0100 Subject: Question - seeding the hw pseudo random number generator In-Reply-To: <20170320132858.GA27044@gondor.apana.org.au> References: <20170318092554.lggkhfg5eko23o3k@kozik-lap> <20170320132858.GA27044@gondor.apana.org.au> Message-ID: <20170323082307.GB16625@Red> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Mar 20, 2017 at 09:28:58PM +0800, Herbert Xu wrote: > On Mon, Mar 20, 2017 at 12:19:32PM +0530, PrasannaKumar Muralidharan wrote: > > > > AF_ALG interface for rng does have seeding support. I think hw_random > > does not provide seeding support intentionally as I understand that > > True RNG need not require seeding (please correct me if I am wrong). > > Yes. We should be converting PRNGs in hwrng over to algif_rng. > Problem with this conversion, a huge regression for user space. Using hwrng is simple as cat /dev/hwrng. Using algif_rng via AF_ALG is ... unusable for the moment. Perhaps creating an user space tool (prng-tool which provide a cat /dev/hwrng replacement) is mandatory before any convertion. Regards