tech-kern: Re: /dev/random without random sources blocking forever?

Subject: Re: /dev/random without random sources blocking forever?
To: =?ISO-8859-1?Q?Jorge_Acereda_Maci=E1?= <jacereda@users.sourceforge.net>
From: Garrett D'Amore <garrett_damore@tadpole.com>
List: tech-kern
Date: 08/21/2006 13:20:59

Jorge Acereda Maciá wrote:
> Hi,
>
> I've noticed that reading from /dev/random without attaching a random
> source (or specifying only a source of type RND_TYPE_NET) blocks
> forever. Is this the intended behaviour?
>
> I'm running -current for ofppc which ATM doesn't attach any random
> sources.

Yes, without random sources, you can't get any entropy bits.  Solution
is to add sources for entropy.  Alternatively, use /dev/urandom which
gives back data without blocking, but might not be cryptographically robust.

    -- Garrett
>
> TIA,
>   Jorge Acereda


-- 
Garrett D'Amore, Principal Software Engineer
Tadpole Computer / Computing Technologies Division,
General Dynamics C4 Systems
http://www.tadpolecomputer.com/
Phone: 951 325-2134  Fax: 951 325-2191