> 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 meant for true RNG, not pseudo RNG. Actually PRNGs should use AF_ALG interface. I think exynos-rng.c should follow the same. > I think the hw_random API does not provide generic infrastructure for > seeding. > > What is the preferred approach for seeding a PRNG device? Use jiffies or > a fixed value? > > Or maybe the interface should be abandoned in favor of crypto API? 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). Regards, PrasannaKumar
