[openwrt/openwrt] urngd: update to the latest master

[Rafał Miłecki]

On 2023-07-25 10:10, Etienne Champetier wrote:
>> commit c74b5e09e692839b39c8325b5f8dc5f2a3b3896c
>> Author: Rafał Miłecki <rafal at milecki.pl>
>> AuthorDate: Tue Jul 25 09:51:35 2023 +0200
>> 
>>     urngd: update to the latest master
> 
> Is urngd still needed/relevant given the 'recent" improvements in
> linux random generator ?

Good question. To be honest I hit urng failing to initialize issue while
resolving multiple years-old BCM53753 regressions over last 2-3 weeks.


So before kernel 5.19 I really needed urng for BCM53753. Without urng it
took over 1,5 hour to initialize crng and start dropbear:
[ 6095.816238] crng init done
or:
[ 6158.675813] crng init done

That was related to the 29e170dbaac0 ("dropbear: bump to 2020.79") as
dropbear started using getrandom().


In kernel 5.19 we've received following random subsystem changes:
ac2ab99072cc ("Merge tag 'random-5.19-rc1-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random"):
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ac2ab99072cce553c78f326ea22d72856f570d88

For BCM53753 the critical change was commit ff8a8f59c99f ("arm: use
fallback for random_get_entropy() instead of zero"):
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ff8a8f59c99f6a7c656387addc4d9f2247d75077


Those random subsystem changes were later backported to stable kernel
releases (e.g. Linux 5.4.200). So for BCM53573 that may make urng
obsolete but I'm not sure about all other cases.