Bugtraq: Re: Flaw in commonly used bash random seed method

[Dave English <dave.english () thus net>]

In message 
<a260a2190604031256g23cf3645s348f829530982b38 () mail gmail com>, Matthijs 
<thotter () gmail com> writes
> By the way, if the random function can only generate numbers between 0
> and 32767, won't 2 bytes be enough then? The algorithm will perform a
> modulo calculation anyway, so 4 bytes won't really add anything. Of
> course, it is much better then only one byte.
That will depend on whether the state stored between calls to the PRNG 
is only 15-bits, or something larger.
If more state is stored than is enumerated in the result, then the 
generator should have more points on its sequence than 32768 .  In that 
case then, seeding with more than 15 bits would be worthwhile.
I have not looked at Bash myself, to see what it actually does
--
Dave English                      Senior Software & Systems Engineer
                             Internet Platform Development, Thus plc

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