[Fwd: Re: FreeBSD Security Advisory FreeBSD-SA-03:12.openssh]

[David G. Andersen]

Devon H. O'Dell just mooed:
>
> If I'm not mistaken, /dev/random is a pseudo-random generator, which 
> means it has a certain period before it begins to repeat numbers (along 
> with that it just isn't truly random). So, please correct me if I'm 
> wrong, but doesn't this mean that when reading from /dev/random, you're 
> 'losing' randomness/entropy/whatever you're calling it?

   You're mistaken.  /dev/random stops feeding you random bits
when it doesn't have enough.  /dev/urandom depletes the entropy
pool, but when it starts to run out, it falls back to hashing
to generate pseudo-random sequences from the random bits that
it can obtain.

  -Dave

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