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Re: getrandom and getentropy (Taylor R Campbell) writes:

>> Date: Mon, 11 May 2020 16:16:12 -0000 (UTC)
>> From: (Michael van Elst)
>> Previously we could trust in random processes, whether the entropy
>> estimation was scientific or not. We could also chose what source
>> to trust.

>Still can.  NetBSD just doesn't do bogus pseudoscientific
>prestidigitation any more.

It doesn't do any entropy estimation anymore.

HWRNG - we trust the driver
constant file - we trust the file
any random process we used before - we ignore it (as far as it is
related to the topic).

>> Now we put all trust in loading a constant file.

>This is still false, just like it was the last time you made this

We only trust a HWRNG and the seed file because only these enter
a non-zero value for entropy. I cannot configure any other source to
do that.

>> >This hardware can reasonably block forever on first boot, due to
>> >the large number of sources of entropy that are no longer measured.
>> Not "can". It does, definitely, always.
>> And it never blocks on second boot.

>This is false.

After initial boot, reading from /dev/random blocks forever.

Rebooting without providing a seed:  /dev/random still blocks forever.

Rebooting after writing a seed once: never blocks again, even when
the file wouldn't change. Technically of course you are right that
before loading the seed in the rc sequence we would still block forever.

>Please do your homework first,

Like checking the code and verifying how it operates ?

>and then take this to a thread where it
>is on topic, not the thread about a choice of C API to adopt.

The discussion seems to be on topic here, even if you don't want it.
After all I responded to an article that exactly put this on topic
but which didn't cause indignation.

                                Michael van Elst
                                "A potential Snark may lurk in every tree."

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