add reversal of sufficiently long PPPs

If you generate a PPP that's sufficiently long by the ppp.exe from GRC (probably at least 20 chars, but if you get exclamation marks at the end [remainder 0] you're good to go) you can reverse the initial quotient, i.e. the encrypted secret.

Author: My1

ppp-rev.php

@@ -0,0 +1,29 @@
+<?php
+require('bigint.php');
+header("Content-Type: text/plain");
+$ppp="L:k66XiKLeiPMYxf8H!5%%!";
+$set="!#%+23456789:=?@ABCDEFGHJKLMNPRSTUVWXYZabcdefghijkmnopqrstuvwxyz"; //character set
+//make set and ppp into array
+$seta=str_split($set);
+$pppa=str_split($ppp);
+//get number array
+$char=array_pop($pppa);
+while($char!==null) {
+  $charna[]=array_search($char,$seta);
+  $char=array_pop($pppa);
+}
+//var_dump($charna); //throw the array
+
+$num=new Math_BigInteger(array_shift($charna));
+$charn=array_shift($charna);
+while($charn!==null) {
+  //bla=bla*set
+  //bla+next
+  //bla+(setxnext)
+  echo "prev: ".$num->toString()." Setcount: ".count($seta)." Remainder (from PPP): ".$charn."\n";
+  $num=$num->multiply(new Math_BigInteger(count($seta)));
+  $num=$num->add(new Math_BigInteger($charn));
+  $charn=array_shift($charna);
+}
+echo "\n\n"."Final Number: ".$num->toString().' Hex: '.$num->toHex();
+?>