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SubjectRe: no entropy and no output at /dev/random (quick question)
From (David Wagner) said:
> Javier Villavicencio wrote:
> >it's encouraged to use /dev/urandom instead of /dev/random?

> Yes, for almost all purposes, applications should use /dev/urandom,
> not /dev/random. (The names for these devices are unfortunate.)

To seed a random number generator, never directly.

> Sadly, many applications fail to follow these rules, and consequently
> /dev/random's entropy pool often ends up getting depleted much faster
> than it has to be.

Reading /dev/urandom depletes exactly the same pool, it just doesn't block
when the pool is empty. As said pool has other uses, indiscriminate reading
of either can DoS other parts of the system.
Dr. Horst H. von Brand User #22616
Departamento de Informatica Fono: +56 32 654431
Universidad Tecnica Federico Santa Maria +56 32 654239
Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513
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