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Re: Noob dumb question (extending emacs)

From: Jean Louis
Subject: Re: Noob dumb question (extending emacs)
Date: Sun, 24 Oct 2021 09:45:43 +0300
User-agent: Mutt/2.0.7+183 (3d24855) (2021-05-28)

* Yuri Khan <> [2021-10-23 13:47]:
> On Sat, 23 Oct 2021 at 04:35, Jean Louis <> wrote:
> > - I have noticed that file "/proc/pressure/io" is constantly
> >   changing, could not find temperature stuff now, thus:
> “Constantly changing” does not mean it is a reliable source of
> randomness (entropy).
> Also, the word “pressure” there does not refer to any physical
> processes. In context, it is a metaphor, referring to the concurrent
> processes in your computer competing for a resource, in this case, the
> input/output system.
> Anyway:
>     $ cat /proc/pressure/io
>     some avg10=0.00 avg60=0.00 avg300=0.05 total=313213969
>     full avg10=0.00 avg60=0.00 avg300=0.04 total=238002455
>     $ cat /proc/pressure/io
>     some avg10=0.13 avg60=1.09 avg300=1.08 total=318142202
>     full avg10=0.13 avg60=0.98 avg300=0.97 total=242407828
> What we have here is some constant text that does not contribute to
> randomness in any way, and a few decimal numbers. A single sampling
> gives you 36 digits. 3 decimal digits ≈ 10 bits, so you could estimate
> 120 bits which would be considered a fair amount of entropy.

Congratulation for the analysis, although myself I cannot follow it.

> (Of course you could just replicate what pwgen does, and read from
> /dev/urandom or /dev/random, and directly convert that into characters
> usable in passwords.)

I agree, though I don't need it personally, as no analyst so far has
cracked any of my Emacs Lisp generated passwords.

I will give US $1,000 if you crack any of my passwords in any of
websites I am subscribed within next 2 years. OK?


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