http://www.perlmonks.org?node_id=245803


in reply to A Hacktress' First Attempt

SarahM++ for a fun obfuscation! You had me going in circles for a few minutes... I felt like I was chasing my tail!

Deobfuscation follows:
First we strip out all the comments being careful to remove *only* the comments. That leaves us with: 
sub p () {
    use constant P=>' )';
    use constant Q=>'* ';
    substr(P,1,1);
}

sub q () {
    eval join '', split /./, s//rxlgcdjqfvbpsohduwyvcmbjdxopd/ & map {
      tr/[a..z]/[z..a]/ . P | Q
  } split //;
}

$, = p;
print q; #Just Another Perl Hacktress ;^P

[download]
That last line fooled you didn't it?

The q subroutine is only there to confuse you and is not used at all. So we strip it out leaving us with: 
sub p () {
    use constant P=>' )';
    use constant Q=>'* ';
    substr(P,1,1);
}
$, = p;
print q; #Just Another Perl Hacktress ;^P

[download]
"What is she up to?", you ask?
$, (output field seperator) is set to the return value of the p subroutine (a space) but the real purpose of the p subroutine is to set the value of the P constant to the string ' )'. $, is not even used so let's strip it down again. 
use constant P => ' )';
print q; #Just Another Perl Hacktress ;^P

[download]
This can be rewritten as:
 print ' #Just Another Perl Hacktress '^' )'

A space XORed with a space yields a null (\000). A number sign (#) XORed with a ) yields a newline (\n).
The output is '\000\nJust Another Perl Hacktress '.

Fixed typo. Thanks LAI!

In Section Obfuscated Code