& (Delphi) Umschreiben einer Funktion

[Andy A.]

Hi,

ich habe diese delphi-Funktion:

// --------------------------------------------------------
Function Encryp(Const S: String; Key: Word; rueckw: Boolean): String;
Var
  I: byte;
  oben, unten: byte;
Begin

Setlength(Result, length(S));
  If Rueckw Then Begin
    For I := Length(S) Downto 1 Do Begin
      Result[I] := char(byte(S[I]) Xor (Key Shr 8));
      Key := (byte(Result[I]) + Key) * C1 + C2;
    End;
  End
  Else Begin
    For I := 1 To Length(S) Do Begin
      Result[I] := char(byte(S[I]) Xor (Key Shr 8));
      Key := (byte(Result[I]) + Key) * C1 + C2;
    End;
  End;

Encryp := result;
End;
// ---------------------------------------------------------

Nun will ich die aus PHP umschreiben. Hier mal ein Versuch:

<!-- ----------------------------- -->
<textarea rows="27" name="S1" cols="70"><?php
$c1=41088;
$c2=88104;

Function encryp($s,$key,$rueckw){
    global $c1,$c2;
  if ($rueckw) {
    For ($i=0;$i<=strlen($s)-1; $i++){

$result.=chr(substr($s,$i,1) ^ ($key >> 8) & 0xff);
      $key = ((ord(substr($result,-1))+$key)*$c1 + $c2) & 0xffff;
       echo  "$key ".($key >> 8)."\n";
    }
  } else {
      For ($i=strlen($s)-1;$i>=0; $i--){
      $result.=chr(ord(substr($s,$i,1) ^ ($key >> 8)));
      $key = (ord(substr($result,-1))+$key)*$c1 + $c2;
    }
}
  return $result;}

$s="testte";
$s1=encryp($s,815,1);
$result=bin2hex($s1);

echo "$s1
$result\n";
$s1= pack("H" . strlen($result),$result);
$result=encryp($s1,815,1);
echo "\n$result";

?></textarea>
<!-- -------------------------------------- -->

Was ist bei der PHP-Funktion falsch?

Andy