Re: Question - seeding the hw pseudo random number generator

2017-03-25 Thread Stephan Müller
Am Donnerstag, 23. März 2017, 10:44:06 CEST schrieb Herbert Xu: Hi Herbert, > On Thu, Mar 23, 2017 at 09:23:07AM +0100, Corentin Labbe wrote: > > 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 ...

Re: Question - seeding the hw pseudo random number generator

2017-03-23 Thread Stephan Müller
Am Donnerstag, 23. März 2017, 10:44:06 CET schrieb Herbert Xu: Hi Herbert, > On Thu, Mar 23, 2017 at 09:23:07AM +0100, Corentin Labbe wrote: > > 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 ...

Re: Question - seeding the hw pseudo random number generator

2017-03-23 Thread Stephan Müller
Am Donnerstag, 23. März 2017, 09:03:23 CET schrieb Harald Freudenberger: Hi Harald, > I'll have a look on it. Currently the s390/crypto/prng seeds itself with > an algorithm based on the jitter of the very fine granular hardware > clock of a s390 machine. There were some thoughts and

Re: Question - seeding the hw pseudo random number generator

2017-03-23 Thread Herbert Xu
On Thu, Mar 23, 2017 at 09:23:07AM +0100, Corentin Labbe wrote: > > 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

Re: Question - seeding the hw pseudo random number generator

2017-03-23 Thread Corentin Labbe
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

Re: Question - seeding the hw pseudo random number generator

2017-03-23 Thread Harald Freudenberger
On 03/20/2017 02:39 PM, Stephan Müller wrote: > Am Montag, 20. März 2017, 14:28:58 CET schrieb Herbert Xu: > > Hi Herbert, > >> 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

Re: Question - seeding the hw pseudo random number generator

2017-03-20 Thread Krzysztof Kozlowski
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

Re: Question - seeding the hw pseudo random number generator

2017-03-20 Thread Stephan Müller
Am Montag, 20. März 2017, 14:28:58 CET schrieb Herbert Xu: Hi Herbert, > 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 >

Re: Question - seeding the hw pseudo random number generator

2017-03-20 Thread Herbert Xu
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.

Re: Question - seeding the hw pseudo random number generator

2017-03-20 Thread PrasannaKumar Muralidharan
> I looked at Exynos Pseudo Random Nubmer Generator driver > (drivers/char/hw_random/exynos-rng.c) and noticed that it always seeds > the device with jiffies. Then I looked at few other drivers and found > that they do not seed themself (or at least I couldn't find this). HW random interface is