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Re: ssh, /dev/urandom



Werner a écrit : 

 > On Tue, 17 Dec 2002 13:36:21 +0100, Gaël Le Mignot said:
 >> And /dev/urandom is not really done for "cryptographic secure" randomness,
 >> it's the goal of /dev/random, not /dev/urandom (and AFAIK ssh only uses

 > That is not really true.  The common implementations of /dev/[u]random
 > for *BSD and Linux use only one entropy pool and the only difference
 > between random and urandom ist that urandom never blocks on low
 > entropy but continues to yield random bytes using a pesudo random
 > number generater (i.e. hashing the pool again).  So, as long as enough
 > entropy is available both devices can be considered equal.

This is the current implementation, yes, but /dev/urandom doesn't guarantee
anything about the "quality" of the random bits. It can be secure, but it
can be pseudo-random too, and any program that use /dev/urandom as a secure
source of random bits is flawed, so there is absolutely no problem, IMHO,
to use the current random translator for /dev/urandom.

-- 
Gael Le Mignot "Kilobug" - kilobug@nerim.net - http://kilobug.free.fr
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