\includes\bootstrap.inc line 784

##</code><code>##


784 ......... session_name ($prefix.substr(hash('sha256', $session_name), 0, 32));


##</code><code>##

....

$data = $drupal_host; #drupal domane name

$dig=&digest_sha($data); #hash of domane name 

$sesionname='SESS'.substr($dig, 0, 32);
$ssesionname='SSESS'.substr($dig, 0, 32);

$valuecook = cookie($sesionname);
$valuecook_s = cookie($ssesionname);

#
#!!! do not forget to check $valuecook_s to safe from $sql injection 
#

&dbopen_d; #my sub to open db

# $d_u_t - drupal user table
# $d_ur_t - drupal user roles table
# $d_r_t - roles table

$sql=qq~SELECT $d_u_t.name, $d_ur_t.rid
              FROM  $d_s_t, $d_u_t, $d_ur_t, $d_r_t
                   WHERE ($d_s_t.sid="$valuecook" OR $d_s_t.ssid="$valuecook_s")
                         AND $d_ur_t.uid=$d_u_t.uid
                         AND $d_s_t.uid=$d_u_t.uid
                         AND $d_u_t.login<UNIX_TIMESTAMP()
                         AND ( UNIX_TIMESTAMP() - $d_s_t.timestamp )<86400~;

my $sth = $dbh->prepare($sql); 
my $rv=$sth->execute or die "xxx"


......

##</code><code>##

sub digest_sha{

use Digest::SHA qw(sha256_hex);
my ($data)=@_;

        $digest1 = sha256_hex($data);
        return $digest1;

}