Hey, I am writing some code for a machine that I cannot guarantee the security of, some of the stuff in it I'd rather keep away from prying eyes, beyond the usual obfuscation methods and such. I remember (...or I might of made this up) reading about a module that would have almost all of the code encrypted under some algorithm and would be decrypted and executed at runtime. Since then I have been completely unable to find any more about this so I decided I would try and have a go myself, my first thought was simply to encrypt a file then write a second script which would prompt for the key then decrypt the file then I would pipe the resulting code printed to the perl interpreter. Apparently this is a baaaaaad idea as it freezes up the interpreter, I can't exit without killing the process. My second thought was to use a perl filter that would encrypt the code with blowfish then request the key so it could decrypt the code but from what I have read about perlfilters this isn't really what it is designed to do...

I was just wondering if anyone could offer any tips or ideas on how this could be accomplished?

In reply to Decrypt source before interpreter by Anonymous Monk

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