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Some days ago, I started to search for a usefull code-snipet to de- and encrypt files or strings in OpenLaszlo. Everything I found were some posts about hash creation. So I started to search for JavaScript solutions to port them to OpenLaszlo. Mixing this with some hash creation algorithms and an own class to handle all those functions is compiled together to “AESCryptLz”. It can be used to de- and encrypt everything you want.
The used algorithm de-/encrypts via AES/ECB without Padding. You can de-/encrypt with a 128 bit key only. To do so, you can either use a 128 bit hex string or an ASCII string as “password”. If you use the ASCII key, then AESCryptLz will generate a MD5 hash out of it, to use it as a 128 bit hex key. All the encrypted data will be returned as a hex string. Also the data you, want to encrypt, needs to be a hex string.
Sounds a bit confusing, but it’s explained at the top of the source code.

To create this little set of classes, I ported a JavaScript library created by Eugene Styer. He allowed me to use his source code under the GPL. Thanks a lot!
I also used an OpenLaszlo class, ported by Userfriendly and former developed by Paul Johnston, released under the BSD licence. Thanks a lot, you too.

I created an own class, modified the mentioned classes and linked them all together. So you can use it under the GPL. Here you can find a little example that makes use of AESCryptLz.

The Sourcecode:

• AESCryptLz source code: aescryptlz.lzx (2009-07-06)
• AESCryptLz example source code: crypttest.lzx (2009-07-06)
• A Java backend example class: aesCrypt.java (2009-07-06)
• The Example: Here

The first one is the AESCryptLz source code. The second one is the code of the shown example. And the third one is a little, quick and dirty Java source code, that shows, how to handle AESCryptLz-encrypted data. This may be usefull for a Java backend.

I’m looking forward to your feedback.

Kind regards,
Mario

Ps.: To see if it works, try to decode the following message, using the example application with the ASCII key “synie”:

1e af f3 90 83 02 50 90 a4 9c bc bc 7e 05 d3 78 50 79 ac aa 0f 0d ad 28 98 a7 46 13 b1 49 d7 e2 b9 d1 d9 c7 7a f0 01 0e 88 0d 95 a3 7f b2 52 92 2f 9e 5b 61 e7 67 8a 93 19 d0 5c c0 0c 78 64 e3 e0 f2 4c 4f b5 64 e9 d8 43 89 9d 8e fb 07 d8 e7 b8 ea 07 49 69 fd a7 b3 8d c3 8b 04 19 92 7a be

A lot of people asked for the source code of GTBot. It’s a C++-based bot for GTChat, which I wrote some years ago. You can download it under the terms of GPL:

• gtbot.tar (2009-07-06)
• gtbot_src.tar (2009-07-06)
• gtbot_readme (2009-07-06)

Beware! The source code is years old. It’s from times when I started to learn C++. So it’s really messed up and absolutely not nice. Better use it as a compilation of some functions for the GTChat, than using the bot in productive use. Everyone is welcome to go through the code, give it a nice OOP structure and send it back to me.