Re: Seeding /dev/random not working

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, May 29, 2007 at 05:44:37PM +0100, M Macnair wrote:
> On 29 May 2007 18:58:59 +0200, Andi Kleen <[email protected]> wrote:
> >"M Macnair" <[email protected]> writes:
> >>
> >> Many distros ship with an init script that saves and restores the
> >> entropy pool on startup and shutdown.  The bit that interests me that
> >> is called on startup is (my comments):
> >>       if [ -f $random_seed ]; then
> >>               cat $random_seed >/dev/urandom  # should seed the pool
> >OA
> >Writing doesn't actually work; to get real accounted entropy for 
> >/dev/random
> >you need to use a special ioctl. I ran into this problem some years ago
> >and ended up writing http://www.muc.de/~ak/rndfeed.c
> >
> >-Andi
> 
> If this doesn't work, then it seems to me as though all the
> debian-esque distros that use equivalents of the above script are
> wasting their time, and the man page recommending that technique (man
> 4 random) is also wrong.  Is that interpretation correct?

Andi is incorrect. Writing does work and everything you write is mixed
into the pool. It's just not counted as entropy credit. This is as
intended.

-- 
Mathematics is the supreme nostalgia of our time.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux