Bug#961729: education-networked-common: Please remove Recommends: haveged

[Petter Reinholdtsen <pere@hungry.com>]

[Wolfgang Schweer]
> 5.6.0-2-amd64 #1 SMP Debian 5.6.14-1 (2020-05-23) GNU/Linux (unstable):
> enabled as a module (jitterentropy_rng).
>
> Unchanged at least since Buster (4.19.x).

Right.  The module do not seem to do a great job in Buster, at least.  I
tried with and without haveged active, and with and without the
jitterentropy_rng kernel module, running

  while time dd bs=1 count=32 if=/dev/random of=/dev/null 2>/dev/null ; do
    cat /proc/sys/kernel/random/entropy_avail
    sleep 1
  done

This pull out 32 bytes of random bits every second while reporting how
long it took to get the bytes.  With haveged active, the entropy_avail
count never go below 1000, without it, entropy quickly drains out.  With
the jitterentropy_rng kernel module, entropy still drain out.  This was
without typing on the keyboard and not moving the mouse.

Note, my laptop have decided to load the tpm module on its own, which
might affect the result.  Not quite sure what it does, but it depend on
rng_core which make me suspect it can be a randomness source.

-- 
Vennlig hilsen
Petter Reinholdtsen