Obfuscate/Encode/Encrypt PHP System Function Names

Question

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Best solution to protect PHP code without encryption

Can anyone tell me if it is okay/acceptable to obfuscate ALL function names in PHP?

For example, this seems to work using an online tool:

Original:

if(file_exists($file)){chmod($file,0644);echo"good";}

Obfuscated:

$x0c="\143hm\x6f\144"; $x0d="\x66\x69\x6ce\x5f\x65\170\151\x73\164\x73"; 
if($x0d($x0b)){$x0c($x0b,0644);echo"go\x6fd";}?>

My questions:

1. Notice it no longer has file_exists or chmod functions, but will this work on any PHP installation setup/version?
2. Using this method, can any PHP function be done such as these: file(), eval(), base64_decode(), file_get_contents(); str_rot13(), strpos(), touch(), filemtime() ?
3. Does this work on windows, linux, etc.. servers?

Answer 1

1. Notice it no longer has file_exists or chmod functions, but will this work on any PHP installation setup/version?
2. Using this method, can any php function be done such as these: file(), eval(), base64_decode(), file_get_contents(); str_rot13(), strpos(), touch(), filemtime() ?
3. Does this work on windows, linux, etc.. servers?

Yes, yes and yes.

Can anyone tell me if it is okay/acceptable to obfuscate ALL function names in PHP?

No, no, and hell no.

So, while this code works, there are a few big problems:

1. The more you obfuscate, the slower the code gets. Simple fact of life.
2. It's trivial for advanced users to simply undo all of your work. If you're trying to obfuscate the source as an anti-piracy measure, you can straight up not bother.
3. If you're trying to obfuscate the source in an attempt to do evil things, beware that this stuff sticks out like a sore thumb as being "wrong" looking and thus is easy to simply remove.
4. Finally, even though you're hiding the names of the functions, you won't be able to bypass PHP's built-in disable_functions configuration setting.