From mboxrd@z Thu Jan  1 00:00:00 1970
From: Theodore Ts'o <tytso-3s7WtUTddSA@public.gmane.org>
Subject: Re: [PATCH, RFC] random: introduce getrandom(2) system call
Date: Thu, 17 Jul 2014 18:27:41 -0400
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To: Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>
Cc: Zach Brown <zab-ugsP4Wv/S6ZeoWH0uzbU5w@public.gmane.org>, Bob Beck <beck-7YlrpqBBQ3VAfugRpC6u6w@public.gmane.org>, Christoph Hellwig <hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, linux-api <linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
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On Thu, Jul 17, 2014 at 03:00:45PM -0700, Andy Lutomirski wrote:
> 
> And we'll be in a sad state in which we have a getrandom(2) syscall
> but there's no decent way to use srand without either opening
> /dev/urandom or mucking with AT_RANDOM.  And the latter barely works
> because I think that most (all?) glibc versions clear it after using
> it to initialize their stack canaries.

Sorry, I really don't think that supporting srand() is a good use of
getrandom(2).  If it's for non-crypto purposes, using getpid() and
time() is *just* *fine*.

If we add such a flag, my big fear is that it gets misused.  Sometimes
it does make sense to create interfaces that a strong point of view.
The primary use of getrandom(2) should be for cryptographic purposes,
and trying to avoid misuse should be the primary objective.

						- Ted