Pascal (Lazarus/Delphi)

56-bit DES Encryption, ECB, CBC modes

See more Encryption Examples

Demonstrates the older 56-bit DES encryption in ECB and CBC modes. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Crypt2;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  crypt: TCrypt2;
  ivHex: string;
  keyHex: string;
  encStr: string;
  decStr: string;

begin
  //  This example assumes the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  crypt := TCrypt2.Create;

  //  Specify DES for the encryption algorithm:
  crypt.CryptAlgorithm := 'des';

  //  CipherMode may be "ecb" or "cbc"
  crypt.CipherMode := 'cbc';

  //  Keylength is 64 bits (56 bits + 8 parity bits)
  crypt.KeyLength := 64;

  //  The padding scheme determines the contents of the bytes
  //  that are added to pad the result to a multiple of the
  //  encryption algorithm's block size.  DES has a block
  //  size of 8 bytes, so encrypted output is always
  //  a multiple of 8.
  crypt.PaddingScheme := 0;

  //  EncodingMode specifies the encoding of the output for
  //  encryption, and the input for decryption.
  //  It may be "hex", "url", "base64", or "quoted-printable".
  crypt.EncodingMode := 'hex';

  //  An initialization vector is required if using CBC or CFB modes.
  //  ECB mode does not use an IV.
  //  The length of the IV is equal to the algorithm's block size.
  //  It is NOT equal to the length of the key.
  ivHex := '0001020304050607';
  crypt.SetEncodedIV(ivHex,'hex');

  //  The secret key must equal the size of the key.  For 
  //  DES, the key must be 8 bytes (i.e. 64-bits).
  keyHex := '0001020304050607';
  crypt.SetEncodedKey(keyHex,'hex');

  //  Encrypt a string...
  //  The input string is 44 ANSI characters (i.e. 44 bytes), so
  //  the output should be 48 bytes (a multiple of 8).
  //  Because the output is a hex string, it should
  //  be 96 characters long (2 chars per byte).
  encStr := crypt.EncryptStringENC('The quick brown fox jumps over the lazy dog.');
  WriteLn(encStr);

  //  Now decrypt:
  decStr := crypt.DecryptStringENC(encStr);
  WriteLn(decStr);


  crypt.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.