upxscrambler.pas

来自「UPXShell 压缩解压缩Windows下的exe和dll文件, 其原理基于加」· PAS 代码 · 共 109 行

unit UPXScrambler;

interface

uses
  Classes, SysUtils;

{Functions/Procedures}
function fScrambleUPX(const FileName: string): boolean;

implementation

(* uses
  Dialogs; *)

function fScrambleUPX(const FileName: string): boolean;
var
  fsSource:    TFileStream;
  GlobalChain: array[1..$2BE0] of char;
  PosString:   integer;
begin
  Result := False;
  try
    fsSource := TFileStream.Create(FileName, fmOpenReadWrite);
    //Scramble UPX0 -> code | UPX0 located in upx v0.6 until present
    fsSource.Position := 0;
    fsSource.ReadBuffer(GlobalChain, $2BDF);
    if pos('UPX0', GlobalChain) <> 0 then
    begin
      PosString := pos('UPX0', GlobalChain);
      fsSource.Position := PosString - 1;
      fsSource.Write('CODE', 4);
      Result := True;
    end;
    //Scramble UPX1 -> text | UPX1 located in upx v0.6 until present
    fsSource.Position := 0;
    fsSource.ReadBuffer(GlobalChain, $2BDF);
    if pos('UPX1', GlobalChain) <> 0 then
    begin
      PosString := pos('UPX1', GlobalChain);
      fsSource.Position := PosString - 1;
      fsSource.Write('DATA', 4);
      Result := True;
    end;
    //Scramble UPX2 -> data | UPX2 located in upx v0.6 until v1.0x
    fsSource.Position := 0;
    fsSource.ReadBuffer(GlobalChain, $2BDF);
    if pos('UPX2', GlobalChain) <> 0 then
    begin
      PosString := pos('UPX2', GlobalChain);
      fsSource.Position := PosString - 1;
      fsSource.Write('BSS'#$00, 4);
      Result := True;
    end;
    //Scramble UPX3 -> data | UPX3 located in upx v0.7x i think.
    fsSource.Position := 0;
    fsSource.ReadBuffer(GlobalChain, $2BDF);
    if pos('UPX3', GlobalChain) <> 0 then
    begin
      PosString := pos('UPX3', GlobalChain);
      fsSource.Position := PosString - 1;
      fsSource.Write('IDATA', 5);
      Result := True;
    end;
    //Scramble OLD '$Id: UPXScrambler.pas,v 1.4 2004/11/21 20:40:27 iont Exp $Id: UPX' located in upx v0.06 until v1.07x
    fsSource.Position := 0;
    fsSource.ReadBuffer(GlobalChain, $2BDF);
    if pos('$Id: UPX', GlobalChain) <> 0 then
    begin
      //Start '$Id: UPX'
      PosString := pos('$Id: UPX', GlobalChain);
      fsSource.Position := PosString - 1;
      //Write 13 times 0 becouse of the version string removal.
      fsSource.Write(#0#0#0#0#0#0#0#0#0#0#0#0#0, 13);
      //Start 'UPX!'
      PosString := pos('UPX!', GlobalChain);
      fsSource.Position := PosString - 1;
      fsSource.Write(#0#0#0#0#0#0, 6);
      Result := True;
    end
    else begin
      //Scramble NEW UPX! -> nil | UPX! located in upx v1.08 until present
      if pos('UPX!', GlobalChain) <> 0 then
      begin
        //-6 Becouse of the version string removal.
        PosString := pos('UPX!', GlobalChain);
        fsSource.Position := PosString - 6;
        fsSource.Write(#0#0#0#0#0#0#0#0#0#0#0, 11);
        Result := True;
      end;
    end;
    //Scramble anything that is left of something called UPX within the header
    fsSource.Position := 0;
    fsSource.ReadBuffer(GlobalChain, $2BDF);
    if pos('UPX', GlobalChain) <> 0 then
    begin
      PosString := pos('UPX', GlobalChain);
      fsSource.Position := PosString - 1;
      fsSource.Write(#0#0#0, 3);
      Result := True;
    end;
  finally
    FreeAndNil(fsSource);
  end;
end;

end.