#!/usr/bin/env perl
use strict;
use warnings;
use Digest;

my $algo = 'SHA-512';

sub hash {
    my $string = shift;
    my $salt;

    # bless whoever wrote this
    $salt .= join '',('.','/',(0..9),"a".."z","A".."Z")[rand 64] for (1..8);

    my $hasher = Digest->new($algo);

    $hasher->add($salt);
    $hasher->add($string);
    return $salt . $hasher->b64digest();
}

sub checkHash {
    # First 8 characters are salt
    my $hash = shift;
    my $string = shift;
    my $salt = substr($hash,0,8);
    my $hasher = Digest->new($algo);
    $hasher->add($salt);
    $hasher->add($string);
    return $hash eq $salt . $hasher->b64digest();
}

my $hash = hash('blahblah');
print "match" if checkHash($hash,'blahblah');