On Wed, 10 Feb 2021 at 23:49, Rebecca Cran <rebe...@nuviainc.com> wrote: > > On 1/15/21 7:51 PM, Sami Mujawar wrote: > > > I have shared some initial thoughts on the RNG implementation updates at > > https://edk2.groups.io/g/devel/files/Designs/2021/0116/EDKII%20-%20Proposed%20update%20to%20RNG%20implementation.pdf > > > > Kindly let me know your feedback or if you have any queries. > The ARMv8.5 RNDRRS instruction appears to be missing from the diagram on > page 11 - it has RngLib|RNDR, which is listed under PRNG, but RNDRRS > returns a true random number. From the Arm ARM: > > "Returns a 64-bit random number which is reseeded from the True > Random Number source immediately before the read of the random number." >
This is an unfortunate oversight in the architecture, but RNDRRS most certainly does not return a true random number. RNDR and RNDRRS both return the output of a DRBG (pseudo RNG), and the only difference is the reseed rate: RNDRRS triggers a reseed on every invocation, whereas RNDR triggers a reseed at an IMPDEF rate. -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#71619): https://edk2.groups.io/g/devel/message/71619 Mute This Topic: https://groups.io/mt/78823009/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
