#!/usr/bin/perl
use strict;
use warnings;
use Digest::MD5 qw (md5_base64);

print "enter a password to store: ";
my $password = <STDIN>;
my $salt = time;
my $digest = md5_base64($password.$salt);

print "salt: $salt hash: $digest\n";

my $enter = 0;
until ($enter) {
    print "Speak friend and enter: ";
    my $try = <STDIN>;
    my $tryhash = md5_base64($try.$salt);
    $enter++ if $tryhash eq $digest;
}
print "Welcome friend\n";
__END__
# output ...
enter a password to store: friend
salt: 1235062413 hash: 2eJWH+Yjy1Fw8J9wW6vmAg
Speak friend and enter: enemy
Speak friend and enter: friend
Welcome friend