Utility of NEUG or Gomti with new LRNG code

[Frédéric SUEL]

Hi!

*Ref 1* : https://www.chronox.de/lrng/doc/lrng.pdf

*Ref 2* : 
https://www.bsi.bund.de/SharedDocs/Downloads/EN/BSI/Publications/Studies/LinuxRNG/LinuxRNG_EN_V5_4.html

Until yet, we can use NEUG with user space utility call rng-tools. But 
since kernel 5.18 and the refondation of the Linux Random Number 
Generator (Ref 1) by stephan Muller ( smueller at chronox.de), it seems 
that : /dev/urandom and /dev/random are the same after initial RNG 
initialization (https://wiki.archlinux.org/title/Rng-tools) and (Ref 2 
page 15 : "/When accessing /dev/random, random numbers are only 
generated if the entropy pool or the ChaCha20 DRNG received at least 256 
bits of initial entropy. After reaching that threshold of 256 bits of 
entropy once, /dev/random will operate non-blocking for the lifetime of 
the system and thus operate identically //to /dev/urandom../")

The BSI (Deutschland Digital Sicher / Budesamt für Sicherheit in der 
Informationstecnik) make regular analysis of the Linux Random Number 
Generator (Ref 2) and it's conclusions are that :

-- the new RNG is not as efficient as it's older implémentation

-- few sources of entropy are correct for entropy boot process (Ref 2 §6.1)

--  When injecting new seed data from user space by either the IOCTL or 
by writing into either /dev/random or /dev/urandom, the seed data is 
added to the input pool. It remains unused there until the base ChaCha20 
DRNG decides it is time to reseed (Ref 2 page 58).

So, it would be interesting to use NEUG and in the futur Gomti as 
hardware generator (Ref 2 pages 39 & 51). It would be interesting for 
early boot process (Ref 2 page 85) and normal process.  It seems to 
replace user space rngd daemon : "/Ref 2 page 39 : The Linux kernel 
contains an additional entropy collection mechanism for in-kernel 
hardware-RNG device drivers. Before the advent of the 
add_hwgenerator_randomness function, the user space rngd daemon was 
required to transport random bits from /dev/hwrng – the interface to the 
hardware-RNG framework – to /dev/random. With the functionality 
described in the following, this detour via user space is //no longer 
needed./"

It is possible, right now, to use it (NEUG, Gomti) as hardware generator 
and how, or will it be possible in the futur ?

Best regards


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.gnupg.org/pipermail/gnuk-users/attachments/20230630/0f64b2e2/attachment.html>