1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:

var n2,e2:TBigNumber;inputf,outputf:String;f,f2:Tfilestream;b:TBigNumber;ok:boolean;t,b2:integer;
...


 n2:=BMD_StrToBigNum(Edit3.Text,false);
 e2:=BMD_StrToBigNum(Edit4.Text,false);
 Gauge1.Progress:=0;
 t:=0;
  f:=TFileStream.Create(inputf,fmOpenRead);
  try
    f2:=TFileStream.Create(outputf,fmCreate);
    try
     while f.Position<f.Size do
      begin
        t:=t+1;
        if(t=10) then begin
          t:=0;
          Gauge1.Progress:=trunc(f.Position/f.Size*100);
           Application.ProcessMessages
       end;
       b2:=0;
        f.read(b2,2);
        b:=BMD_StrToBigNum(inttostr(b2),false);
        b := FastExpMod(b,e2,n2);
        f2.writebuffer(b,SizeOf(b));
      end;
    finally
      f.Free;
    end
  finally
     f2.Free;
  end;
  Gauge1.Progress:=100;
  showmessage('Datei verschlüsselt!');					

1:
2:

Function BMD_StrToBigNum(Str: String; HexInput: Boolean): TBigNumber;
Function BMD_BigNumToStr(Num: TBigNumber; HexOutput: Boolean): String;					

1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:

Function BMD_BigNumToStr(Num: TBigNumber; HexOutput: Boolean): String;
Var
    B, R: TBigNumber;
    X: Integer;
Begin
    Result := '';
    If HexOutput Then
      Begin
        //Zahl auf minimale Länge bringen
      BM_Optimize(Num);
        //HexString erzeugen
      For X := 0 To High(Num) Do
        Result := IntToHex(Num[X], 2) + Result;
       {//Führende Nullen entfernen , nach Optimize maximal 2 (bei Num = 0)
        Dass darf nicht genutzt werden
        While Length(Result) <> 0 Do
            If Result[1] <> '0' Then
                Break
            Else
                Delete(Result, 1, 1);
        
        If Result = '' Then
            Result := '0';
        }
    
      End
    Else					

1:
2:
3:
4:
5:
6:

//schreiben
writeln(TextDatei,BMD_BigNumToStr(Num,True));
//lesen
readln(TextDatei,strBigNum);
Num :=BMD_StrToBigNum(strBigNum,true);
strBigNum :='';