The ^ operator does bitwise XOR, and you're doing something called XOR encryption. Check the web for explanations on how it works.

In my experience, programs that need to "casually" encrypt some data will use this algorithm, because it is so simple to implement. For instance, I have a telnet program that stores configuration information (including the password) in a plain text file. It uses XOR encryption to encode the password in the file.

One of the biggest weaknesses of this method is that if you can get a hold of both the encrypted and the unencrypted version of a value, you can decode the key using XOR as well: 
#!/usr/bin/perl

$toBeEncrypted = "hi there";
$key = "nikos";

$encrypted = $toBeEncrypted ^ $key;

print $encrypted ^ $toBeEncrypted; # Prints "nikos"

[download]

In reply to Re: Simple Encryption question by crashtest
in thread Simple Encryption question by Nik

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.