I suggest you read my rather comprehensive answer to your coding problems with this script posted at Re: To register or not (2)!!! which shows you how to do this as well as fixing a number of other issues with your script.

You have to be joking about using ROT13 encryption right? - that cipher was broken when Ceasar was king. If you want to store passwords you don't need a crappy weak pointless cipher like that. Just do this: 

my $password = password(5);
my $salt = 'Na';   # any two char string will do
my $encrypted = crypt( $password, $salt );
print "The encrypted version of $password is $encrypted\n";

print 'Gimmee the password: ';
chomp( my $answer = <> );
print check_password($answer) ? "OK" : "Wrong";

sub check_password {
    my $to_check = shift;
    # I would normally use return COND ? TRUE : FALSE;
    # like this
    # return (crypt( $to_check, $salt ) eq $encrypted) ? 1 : 0;
    # but here it is in baby perl
    if ( crypt( $to_check, $salt ) eq $encrypted ) {
      return 1
    } else {
      return 0
    }
}

sub password{
    my $s = shift;
    srand( $s ^ time ^ $$ );
    @c = split //, "bcdfghjklmnpqrstvwxyz";
    @v = split //, "aeiou";
    my $password = '';
    $password .= $c[int(rand(21))] .$v[int(rand(5))] for 1..4;
  return $password;
}

[download]

crypt is a one way hashing algorithm so to check a password you encrypt it and see it it matches the encrypted password. You only store the encrypted password. You can't decrypt one way hashes - thus they are generally more secure than ciphers as the only real way to attack them is a brute force dicttionary attack where you encrypt words and see if they match the hashed value.

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: ??Mnemonic Passwords?? by tachyon
in thread ??Mnemonic Passwords?? by eoin

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