Greetings monks

I am transmitting data over a plain text connection and I need a way of encrypting and decrypting the data using only core perl functions since the receiving end is an embedded platform using a basic installation of perl with no modules. On top of that, crypt isn't implemented in perl :) I've tried using pack('C*', unpack('C*', $string)), but it's returning control characters for some non aZ-zZ0-9 characters on decoding (new‡7\cU\cM\cK\cK?3\cM\cKQ\cK\cW).

I saw a two line implementation of the rsa algorithm in perl but I'm looking for something more lightweight because the client only has 8 megs of ram and a small processor. I've looked at rot13 implementations in perl but to quote, 'it is not much stronger than a one meter cardboard fence'. Any thoughts? Remember, I can't use any modules.

update - a shared secret approach here would be fine, my main concern is putting some level of security in so that the data is not there for the taking.

update - thanks to perrin for the spot, Crypt::Blowfish_PP is a module with no dependencies and uses perl core functions only, I'm going to try it out on my broadcom embedded platform.

update - embedded Blowfish_PP successfully, it takes 12 seconds to construct the blowfish object but hey it works!

In reply to Encryption using perl core functions only by redhotpenguin

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