What's wrong with XOR encryption?

Posted by Colin on Stack Overflow See other posts from Stack Overflow or by Colin
Published on 2009-07-16T02:52:03Z Indexed on 2010/06/07 23:12 UTC
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security

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encryption

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xor

I wrote a short C++ program to do XOR encryption on a file, which I may use for some personal files (if it gets cracked it's no big deal - I'm just protecting against casual viewers). Basically, I take an ASCII password and repeatedly XOR the password with the data in the file.

Now I'm curious, though: if someone wanted to crack this, how would they go about it? Would it take a long time? Does it depend on the length of the password (i.e., what's the big-O)?

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