Re: devotee (debian vote engine): predictable RNG allows recovery of secret monikers

[Raphael Geissert <geissert@debian.org>]

Timo Juhani Lindfors wrote:
> True. We need to both fix the RNG and use a longer moniker.

M = H(CRYPT_PRNG())

for example:

use Digest::SHA qw(sha1_hex);

open(UR, '<', '/dev/urandom') or die($!);

my $rbytes;
die if (sysread(UR, $rbytes, 16) < 16);

my $m = sha1_hex($rbytes);


And while at it, stop reinventing the wheel and use a proper HMAC if that's 
what is wanted:

use Digest::SHA qw(hmac_sha1_hex);

print hmac_sha1_hex($v, $m);

Then you just publish the HMAC in the tally.

Cheers,
-- 
Raphael Geissert - Debian Developer
www.debian.org - get.debian.net