One-time pads can be implemented much more easily than that. Just create a string of random characters the same length as your message (we'll call it $key), then do this:

my $encrypted = $message ^ $key;
my $decrypted = $encrypted ^ $key;

[download]

This will result in a ciphertext which is full of non-printable characters, but you can base64 encode it (MIME::Base64 has been in core since before Perl 5.8).

The problem with one-time pads is that the keys are very long (same length as the message) and need to have a decent amount of randomness, so cannot be committed to memory. They need to be stored somewhere.

toby döt ink

In reply to Re^2: crypto with core modules only by tobyink
in thread crypto with core modules only by morgon

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