On 06.06.2018 15:11, Stephan Mueller wrote: > Am Mittwoch, 6. Juni 2018, 14:48:33 CEST schrieb Harald Freudenberger: > > Hi Harald, >> I am still searching for a way to provide our good hardware entropy >> source to the random pool in the random device driver. So I'd like to >> have a new arch interface which is called when the random pool finds >> out that it is running out of entropy. My feeling is that it should >> not be the only source but should still be mixed with other sources >> of entropy. It should not be able to dominate or occupy the random >> pool but contribute to a significant part. >> >> As nowadays true random generators provide conditioned data usually >> with some kind of hashing algorithm a granularity of 4 or 8 bytes is >> waste of random entropy. The s390 TRNG uses SHA512 and can provide >> 64 bytes entropy with each invocation. Other TRNGs may use sha1 or >> sha256 and so provide 20 or 32 bytes of random. However, the API >> could be something like: >> >> int arch_get_entropy(void *buf, int bufsize); > > Why not using the add_hwgenerator_randomness with a kernel thread that is > controlled/spawned from the noise source? > > Ciao > Stephan Had a short glimpse to the mentioned add_hwgenerator_randomness() and this looks in fact like the API I am looking for :-) Thanks Stephan, I'll write some code and check this out. regards H.Freudenberger >
