PHP used to generate machine code, to others to calculate the number to use, how to break?

PHP used to generate machine code, to others to calculate the number to use, how to break?
The following is the decrypted source code, before the source code is encrypted;

This machine code will be generated. Machine code: BDC16D-1843D62D2956-2D2956EEF3A8-F3A8


The science of the information looks like the MD5 turn 16 into the system what, there will be cracked master did not?


<?php
$get _string = "TYCFTKHUVOJHJHPC";
function Strtomd5_pass ($STR)
{
Global $get _string;
return MD5 (MD5 ($STR. $get _string). $get _string);
}
$macmd 5str = Get_current_user (). Php_sapi_name (). Php_version.php_uname (). Default_include_path;
$macmd 5str = substr (Strtomd5_pass ($macmd 5str), 0,24);
$robotstr = substr ($macmd 5str,0,6). " -". substr ($macmd 5str,6,12)." -". substr ($macmd 5str,12,20)." -". substr ($macmd 5str,20,35);
$robotstr = Strtoupper ($ROBOTSTR);
$macmd 5towstr = substr (Strtomd5_pass ($ROBOTSTR), 0,24);
$macmd 5towstr = strtoupper ($macmd 5towstr);
$robotwostr = substr ($macmd 5towstr,5,6). " -". substr ($macmd 5towstr,6,7)." -". substr ($macmd 5towstr,3,6)." -". substr ($macmd 5towstr,2,8);
$file _name= "Key.txt";
$FP =fopen ($file _name, ' R ');
$buffer =fgets ($FP);
if ($robotwostr! = $buffer)
{
Fclose ($FP);
echo "Machine code:". $robotstr;
echo "<br>";
echo "Please contact www.heimaoxuexi.com to register as the official version!" ";
Exit
}

What I want to know at the moment is how this is encrypted. Or how to calculate the machine code: BDC16D-1843D62D2956-2D2956EEF3A8-F3A8 such a machine code. The simple judgment is under $get_string = "TYCFTKHUVOJHJHPC"; TYCFTKHUVOJHJHPC this to generate the machine code, also do not know to say right, have to get PHP Daniel help write a computer code source well?

PHP used to generate machine code, to others to calculate the number to use, how to break?