### Thread: Beginner's encryption

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#### Beginner's encryption

I would like to encrypt the password for my program so that users cant easily open it up and change it. Also, I want to learn how to write it myself instead of using some library file, can someone be kind enough to do a simple demonstration on how to encrypt and decrypt?
2. Well there are literally dozens of encryption methods, from the very simple Caesar cypher (A = B, B = C, C = D, etc.) to RSA.

You could use the md5 or sha modules ; just look at Python's library reference under section 15: cryptographic services.

If you really want to code your own, though, you should look for the Handbook of Applied Cryptography which is completely free. Not a beginner's book, though, but a precious resource nonetheless.
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Interesting, I'd read the doc and md5 looks like a nice choice, I think I'll use that first b4 I write myself one, but how do you decrypt/undigest the encrypted/digested passwords?
4. MD5 is nice, definatly one of the most well used encryptions.. the bad (or good depending on how you look at it) thing about this being there is no decryption, MD5 purly one way!

So if your working with passwords you're actually gonna need to compare rather than decrypt

Mark.
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I've used this before, it works pretty well: http://home.pacific.net.au/~twhitema/des.html

This implementation is written in pure python, there is another written in C floating around somewhere, but I found the one I listed above to be a little easier to use. I think the C one implements other algorithms than DES and 3DES.
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Or maybe I'll use rotor, is that a bad choice?
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yes rotor is bad choice

Use md5 if it is for securing passwords.
It's one of most secure things. And that is due to the fact that you can't unencrypt it (unless you for a very long time anyway). Only compare the md5'ed inputted password to the stored md5-ed password
8. Add that to the fact that rotor was found to be insecure and was depreciated in Python 2.3 and i'm with Yogi on this one . Stick with md5...

Mark.