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Pascal (Lazarus/Delphi)

AES Encryption ECB Mode with PKCS7 Padding

See more Encryption Examples

Duplicates the following C# code:
public static byte[] DecryptBySymmetricKey(string encryptedText, byte[] key)
  {
     string keyAsBase64 = Convert.ToBase64String(key);

     byte[] dataToDecrypt = Convert.FromBase64String(encryptedText);
     var keyBytes = key;
     AesManaged tdes = new AesManaged();
     tdes.KeySize = 256;
     tdes.BlockSize = 128;
     tdes.Key = keyBytes;
     tdes.Mode = CipherMode.ECB;
     tdes.Padding = PaddingMode.PKCS7;
     ICryptoTransform decrypt__1 = tdes.CreateDecryptor();
     byte[] deCipher = decrypt__1.TransformFinalBlock(dataToDecrypt, 0, dataToDecrypt.Length);
     tdes.Clear();
     string EK_result = Convert.ToBase64String(deCipher);
     return EK_result;
}

Chilkat Pascal (Lazarus/Delphi) Downloads

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;
  keyAsBase64: string;
  encryptedBytesAsBase64: string;
  EK_result: string;

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

  crypt := TCrypt2.Create;

  //  In the C# code above that is to be duplicated here, use the base64 encoded key.
  keyAsBase64 := '...';
  encryptedBytesAsBase64 := '....';

  crypt.KeyLength := 256;
  crypt.CryptAlgorithm := 'AES';
  crypt.CipherMode := 'ecb';
  crypt.PaddingScheme := 0;
  crypt.SetEncodedKey(keyAsBase64,'base64');

  crypt.EncodingMode := 'base64';

  //  Pass the base64 representation of the encrypted data.
  //  (The EncodingMode indicates you are passing base64.)
  EK_result := crypt.DecryptStringENC(encryptedBytesAsBase64);

  WriteLn(EK_result);


  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.