Due to a Stackoverflow Post I got to know the fact the BCM2708 / BCM2835 contains a Hardware Random Number Generator (RNG). Two blogposts described how to setup this little module, however, they were outdated, as the needed kernel module is directly baked into the latest 4.x kernel, which ends with the fact that /dev/hwrng already exists :).
The only thing left to do is the installation of the rng-tools, which is easy as pie:
sudo apt-get update sudo apt-get install -y rng-tools
After that, we also need to point rng-tools to the right source, by adding
HRNGDEVICE=/dev/hwrng
to /etc/default/rng-tools (need root rights for that :))
After that, the service can be restarted and used:
sudo service rng-tools restart
PS: This RNG seems to be available on all other RPis as well, not only RPi 1 🙂
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