Шифрование файлов методом перестановки с двумя ключевыми словами

unit Uni;
interface
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls, ComCtrls, ActnList;
type
  TForm1 = class(TForm)
    Button1: TButton;
    LabeledEdit1: TLabeledEdit;
    Button2: TButton;
    RadioGroup1: TRadioGroup;
    OpenDialog1: TOpenDialog;
    ActionList1: TActionList;
    Coding: TAction;
    Decoding: TAction;
    LabeledEdit3: TLabeledEdit;
    Button3: TButton;
    procedure Button1Click(Sender: TObject);
    procedure RadioGroup1Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure CodingExecute(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure DecodingExecute(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
var
  Form1: TForm1;
  in_file,out_file:file;
  key:array[1..8] of longint;
  x1,x2,y1,y2:longint;
  fp1:string;
  i,i1:integer;
implementation
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
begin
 case RadioGroup1.ItemIndex of
   0:Coding.Execute;
   1:Decoding.Execute;
 end;
end;
procedure TForm1.RadioGroup1Click(Sender: TObject);
begin
 case RadioGroup1.ItemIndex of
   0:
    begin
     Button1.Caption:='Êîäèðîâàòü';
     Form1.Caption:='Ðåæèì êîäèðîâàíèÿ';
    end;
   1:
    begin
     Button1.Caption:='Äåêîäèðîâàòü';
     Form1.Caption:='Ðåæèì äåêîäèðîâàíèÿ';
    end;
 end;
end;
procedure TForm1.Button3Click(Sender: TObject);
begin
 OpenDialog1.Filter:='Ôàéë êëþ÷à|*.kf';
 if OpenDialog1.Execute=true
 then
  if FileExists(OpenDialog1.FileName)=false
  then
   begin
    AssignFile(in_file,OpenDialog1.FileName+'.kf');
    rewrite(in_file,1);
    randomize;
    for i:=1 to 32 do
     begin
      i1:=random(255);
      BlockWrite(in_file,i1,1);
     end;
    Closefile(in_file);
    AssignFile(in_file,OpenDialog1.FileName+'.kf');
    reset(in_file,1);
    for i:=1 to 8 do
     BlockRead(in_file,key[i],4);
    Closefile(in_file);
    LabeledEdit3.Text:=OpenDialog1.FileName+'.kf';
   end
  else
   begin
    AssignFile(in_file,OpenDialog1.FileName);
    reset(in_file,1);
    for i:=1 to 8 do
     BlockRead(in_file,key[i],4);
    CloseFile(in_file);
    LabeledEdit3.Text:=OpenDialog1.FileName;
   end;
end;
procedure TForm1.CodingExecute(Sender: TObject);
begin
 if FileExists(LabeledEdit1.Text)=false
 then
  begin
   MessageDlg('Íå âûáðàí êîäèðóåìûé ôàéë',mtError,[mbOK],1);
   Exit;
  end
 else
  if FileExists(LabeledEdit3.Text)=false
  then
   begin
    MessageDlg('Íå âûáðàí êëþ÷åâîé ôàéë',mtError,[mbOK],1);
    Exit;
   end
 else AssignFile(in_file,fp1);
 AssignFile(out_file,fp1+'cf');
 Reset(in_file,1);
 Rewrite(out_file,1);
 for i:=1 to FileSize(in_file) div 8 do
  begin
   BlockRead(in_file,x1,4);
   BlockRead(in_file,x2,4);
   for i1:=1 to 8 do
    begin
     y2:=x1 xor key[i1];
     y1:=x2 xor y2;
     x1:=y1;
     x2:=y2;
    end;
   BlockWrite(out_file,y1,4);
   BlockWrite(out_file,y2,4);
  end;
 i:=filesize(in_file)-filepos(in_file);
 case i of
  1,2,3,4:
   begin
    BlockRead(in_file,x1,i);
    x2:=0;
    for i1:=1 to 8 do
     begin
      y2:=x1 xor key[i1];
      y1:=x2 xor y2;
      x1:=y1;
      x2:=y2;
     end;
    BlockWrite(out_file,y1,4);
    BlockWrite(out_file,y2,4);
   end;
  5,6,7:
   begin
    BlockRead(in_file,x1,4);
    BlockRead(in_file,x2,i-4);
    for i1:=1 to 8 do
     begin
      y2:=x1 xor key[i1];
      y1:=x2 xor y2;
      x1:=y1;
      x2:=y2;
     end;
    BlockWrite(out_file,y1,4);
    BlockWrite(out_file,y2,4);
   end;
 end;
 Closefile(in_file);
 Closefile(out_file);
 MessageDlg('Êîäèðîâàíèå çàêîí÷åííî',mtWarning,[mbok],1);
end;
procedure TForm1.Button2Click(Sender: TObject);
begin
 case RadioGroup1.ItemIndex of
   0:
    begin
     OpenDialog1.Filter:='Âñå ôàéëû |*.*';
     if OpenDialog1.Execute=true
     then fp1:=OpenDialog1.FileName
    end;
  1:
   begin
    OpenDialog1.Filter:='Âñå çàêîäèðîâàííûå ôàéëû |*.*cf';
    if OpenDialog1.Execute=true
    then fp1:=OpenDialog1.FileName
   end;
 end;
 LabeledEdit1.Text:=fp1;
end;
procedure TForm1.DecodingExecute(Sender: TObject);
begin
 if FileExists(LabeledEdit1.Text)=false
 then
  begin
   MessageDlg('Íå âûáðàí äåêîäèðóåìûé ôàéë',mtError,[mbOK],1);
   Exit;
  end
 else
  if FileExists(LabeledEdit3.Text)=false
  then
   begin
    MessageDlg('Íå âûáðàí êëþ÷åâîé ôàéë',mtError,[mbOK],1);
    Exit;
  end
 else AssignFile(in_file,fp1);
 AssignFile(out_file,copy(fp1,1,length(fp1)-2));
 Reset(in_file,1);
 Rewrite(out_file,1);
 for i:=1 to FileSize(in_file) div 8 do
  begin
   BlockRead(in_file,y1,4);
   BlockRead(in_file,y2,4);
   for i1:=8 downto 1 do
    begin
     x1:=y2 xor key[i1];
     x2:=y2 xor y1;
     y1:=x1;
     y2:=x2;
    end;
   BlockWrite(out_file,x1,4);
   BlockWrite(out_file,x2,4);
  end;
 i:=filesize(in_file)-filepos(in_file);
 case i of
  1,2,3,4:
   begin
    BlockRead(in_file,y1,i);
    y2:=0;
    for i1:=8 downto 1 do
     begin
      x1:=y2 xor key[i1];
      x2:=y2 xor y1;
      y1:=x1;
      y2:=x2;
     end;
    BlockWrite(out_file,x1,4);
    BlockWrite(out_file,x2,4);
   end;
  5,6,7:
   begin
    BlockRead(in_file,y1,4);
    BlockRead(in_file,y2,i-4);
    for i1:=8 downto 1 do
     begin
      x1:=y2 xor key[i1];
      x2:=y2 xor y1;
      y1:=x1;
      y2:=x2;
     end;
    BlockWrite(out_file,x1,4);
    BlockWrite(out_file,x2,4);
  end;
 end;
 Closefile(in_file);
 Closefile(out_file);
 MessageDlg('Äåêîäèðîâàíèå çàêîí÷åííî',mtWarning,[mbok],1);
end;
end.

unit Unit1;
interface
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Buttons, Grids, XPMan;
type
  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    Knopka1: TBitBtn;
    Edit1: TEdit;
    XPManifest1: TXPManifest;
    Shifr: TButton;
    MainMemo: TMemo;
    Save: TButton;
    Label1: TLabel;
    procedure FormActivate(Sender: TObject);
    procedure Knopka1Click(Sender: TObject);
    procedure ShifrClick(Sender: TObject);
    procedure SaveClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
var
  Form1: TForm1;
  i,x,y,z,r,o,a,a2,a3,m,mx,m0: byte;
  Text0,Text1: String;
  ShifrStolb: array [1..7] of byte = (1,2,3,7,6,5,4); //êëþ÷ ê ñòîëáöàì 7 öèôð
  ShifrStrok: array [1..6] of byte = (1,2,6,3,5,4); //êëþ÷ ê ñòðîêàì 6 öèôð
  Hash: array [1..42] of string;
//---Save-----------------------------------------------------------------------
  F:TextFile;
  u,g:integer;
  so:string;
implementation
{$R *.dfm}
//-----------------------Íóìåðàöèÿ StringGrid-----------------------------------
procedure TForm1.FormActivate(Sender: TObject);
begin
  for x := 1 to StringGrid1.RowCount-1 do
    StringGrid1.Cells[0,x]:= inttostr(StringGrid1.Row+x-1);
  for y := 1 to StringGrid1.ColCount-1 do
    StringGrid1.Cells[y,0]:= inttostr(StringGrid1.Col+y-1);
  Shifr.Enabled:= False;//âûêë.êí. øèôð
  Save.Enabled := False;
end;
// -Ïðîâåðêà ñèìâîëîâ íà êîëè÷åñâî è èçìåíåíèå ïðîáåëîâ íà äðóãèå ñèìâîëû-------
procedure TForm1.Knopka1Click(Sender: TObject);
begin
  m :=(StringGrid1.RowCount-1)*(StringGrid1.ColCount-1); m0 :=m-1;
  Shifr.Enabled:= True;
  Text0 := edit1.Text;
  i := length(Text0);
  if i > m then ShowMessage ('Âû ââåëè áîëüøå '+inttostr(m)+' ñèìâîëîâ.Ëèøíèå îáðåçàíû!');
  if i < m then ShowMessage ('Âû ââåëè ìåíüøå '+inttostr(m)+' ñèìâîëîâ. Äàííûå ñîõðàíåíû.');
    SetLength (Text0,m);
  for mx := 0 to m0 do
  begin
  if Text0[mx] = ' ' then Text0[mx] := #63;//çàïîëíåíèå ? ìåæäó ñëîâàìè
  end ;
  for mx := i to m0 do Text0[mx+1] := #63; //çàïîëíåíèå ? ëèøíåãî ïðîñòðàíñòâà
end;
//------------------ Ñîðòèðîâêà ïî ñòîëáöàì ------------------------------------
procedure TForm1.ShifrClick(Sender: TObject);
begin
 y:=1; x:=1; o:=1; a:=1; a2:=1; a3:=1;
for y := 1 to StringGrid1.RowCount-1 do
  begin
    for x := 1 to StringGrid1.ColCount-1 do
     begin
     StringGrid1.Cells[ShifrStolb[x],y]:= Text0[o];
     o:=o+1;
    end
   end;
//---------------------êîïèðîâàíèå ñòðîêè â êåø---------------------------------
  begin
    for y := 1 to StringGrid1.RowCount-1 do
  begin
    for x := 1 to StringGrid1.ColCount-1 do
     begin
     Hash[a]:=StringGrid1.Cells[x,y];
     a:=a+1;
   end ;
  end;
//------------------ Ñîðòèðîâêà ïî ñòðîêàì -------------------------------------
  begin
  for x := 1 to  StringGrid1.ColCount-1 do
  begin
    for y := 1 to StringGrid1.RowCount-1 do
     begin
     StringGrid1.Cells[x,ShifrStrok[y]]:= Hash[a2];
     a2:=a2+1;
    end;
   end;
//-----------------------Âûâîä øèôðà--------------------------------------------
 begin
    for y := 1 to StringGrid1.RowCount-1 do
    begin
      for x := 1 to StringGrid1.ColCount-1 do
      begin
      Text1:= Text1+(StringGrid1.Cells[x,y]);
      a3:=a3+1 ;
     end;
     end;
     MainMemo.Lines.Add(text1);
     SetLength(Text1,0);
     Shifr.Enabled:= False;
     Save.Enabled := True;
    end;
   end;
 end;
end;
//---------------Çàïèñü â Ôàéë--------------------------------------------------
procedure TForm1.SaveClick(Sender: TObject);
begin
  AssignFile(f,'Result.txt');
  Rewrite(f);
  for u:=0 to StringGrid1.RowCount-1 do begin
    so:='';
    For g:=0 to StringGrid1.ColCount-1 do
      so:=so+StringGrid1.Cells[g,u]+' ';
    writeln(f,so);
    writeln(f,'');
  end;
  CloseFile(f);
  Save.Enabled := False;
  end;
end.