genode/repos/pc
Martin Stein ab0bce77ec lx_emul & wireguard & wifi: centralized random.cc
Both the Wifi driver and the WireGuard port used local implementations for
their source of randomness. Wifi used a Xoroshiro128+ PRNG for rapid generation
of random values but initialized this PRNG always with the same static seed
value. WireGuard, in contrast, requested each random byte directly from the
jitterentropy lib, which is considered to be very time intensive.

This commit removes the local variants of random.cc and introduces a new
centralized lx_emul/random.cc . The new variant combines the former approaches,
so, that jitterentropy is accessed only in order to generate a random seed for
a Xoroshiro128+ PRNG. Front-end requests for random values are then fulfilled
efficiently via the PRNG.

:Warning:

The output of the Xoroshiro128+ PRNG that is used in the new implementation of
the lx_emul randomness functions has known statistical problems (see
https://en.wikipedia.org/wiki/Xoroshiro128%2B#Statistical_Quality).
Furthermore, the integration of Xoroshir128+ with the lx_emul code was not
reviewed/audited for its security-related properties, so far, and has the
known deficiency of seeding the PRNG only once during initialization. Thus,
we strongly advise against the use of the lx_emul randomness functions for
security-critical purposes.

Ref #4397
2022-05-25 12:23:03 +02:00
..
lib lx_emul & wireguard & wifi: centralized random.cc 2022-05-25 12:23:03 +02:00
recipes lx_emul & wireguard & wifi: centralized random.cc 2022-05-25 12:23:03 +02:00
run Remove legacy intel display driver 2022-05-25 12:23:02 +02:00
src lx_emul & wireguard & wifi: centralized random.cc 2022-05-25 12:23:03 +02:00
README Introduce pc repository for PC board support 2022-02-15 10:23:16 +01:00

               ================================
               Genode support for x86-based PCs
               ================================


This repository complements the Genode OS framework (https://genode.org) with
the board support needed to use Genode on devices based on x86 PCs.

License
-------

Genode-specific code is provided under Genode's regular open-source license,
which is AGPLv3 + open-source linking exception. This code is also available
under a commercial license offered by Genode Labs.

For code ported from other projects - e.g., device drivers ported from the
Linux kernel - the license of the originating upstream project applies.

Please refer to the individual file headers for detailed information.