Understanding what a EVAL and base_decoder is doing

[blmg2009]

Hi, 

 

I have the following code on one of my stores and I have been supplied a code which is below with base 64 code; However before running the code I would like to understand what is it doing. 

 

What changes will it make. 

 

Is there any way of outputting the actual PHP it is eval() -ing 

$GBAY = ' $tXkE = ' $wQMZ = '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';$rM = '$WJZ = base64_decode($wQMZ); eval($WJZ);';eval($rM);';$vO = '$aEC = base64_decode($tXkE); eval($aEC);';eval($vO);';$xm = '$BPk = base64_decode($GBAY); eval($BPk);'; eval($xm);

I'm also wishing to learn more about this type of code and how I could use it myself, I believe it's like inception or something it has amazed me.  

 

 

[blmg2009]

After decoding it I finally found what it was, however what type of practice is there anywhere that I could learn more about it. It has really interested me.  

[benanamen]

When someone has gone to that much trouble to hide code it is pretty much always a backdoor hacker script.

[requinix]

When someone has gone to that much trouble to hide code it is pretty much always a backdoor hacker script.

Either an exploit, or legitimate code that a seller wants to "protect" from prying eyes.

 

blmg2009, there's good news and bad news. The bad news is that we can't help you decode something that's under license, which the stuff you posted is. (Normally I would remove licensed code, but what you posted isn't... well, it's harmless to have exposed.) The good news is that you want to understand how it works, not to break it apart. A fine line indeed.

 

It's a horrible practice and wastes system resources doing a lot of stupid work, but some people think it's what they have to do to protect their code. Maybe they don't know much about licensing, or maybe they think it's truly effective, or what else I don't know. But the basic idea is to be able to give someone some code that works without being readable by a human.

With PHP that's typically some combination of base64_decode() and gzinflate() that ultimately produces some code which can be eval()ed. Do that over and over again and eventually you get actual code that does actual stuff. It's like layers of an onion, except peeling onions isn't as painful.