Pascal (Lazarus/Delphi)

Generate a Random 256-bit AES Key and RSA Encrypt

See more RSA Examples

Generates a random 256-bit AES key and encrypts using an RSA public key. Only the owner of the RSA private key will be able to decrypt the AES key. 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.BinData,
  Chilkat.Rsa,
  Chilkat.PublicKey,
  Chilkat.Prng;

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

procedure RunDemo;
var
  success: Boolean;
  pubKey: TPublicKey;
  rsa: TRsa;
  bdAesKey: TBinData;
  prng: TPrng;

begin
  success := False;

  //  The RSA public key is used for encryption, and the private key for decryption.

  //  The public key's role is to make encryption accessible to anyone while ensuring that
  //  only the private key holder can decrypt the messages.
  //  The public key is designed to be widely distributed so anyone can use it to encrypt messages
  //  intended for the owner of the private key.

  //  Load our 2048-bit RSA public key.
  pubKey := TPublicKey.Create;
  //  In all Chilkat methods expecting a path, you pass either absolute or relative paths.
  success := pubKey.LoadFromFile('rsaKeys/Test2048Rsa.pem');
  if (success = False) then
    begin
      WriteLn(pubKey.LastErrorText);
      Exit;
    end;

  rsa := TRsa.Create;

  //  Tell RSA to use the public key.
  rsa.UsePublicKey(pubKey);

  //  Generate a random 256-bit AES key (32 bytes)
  bdAesKey := TBinData.Create;
  prng := TPrng.Create;
  prng.GenRandomBd(32,bdAesKey);

  //  RSA encrypt.
  rsa.EncryptBd(bdAesKey,False);

  //  Save the RSA encrypted AES key to a file.
  success := bdAesKey.WriteFile('rsaEncrypted/myAes.key');


  pubKey.Free;
  rsa.Free;
  bdAesKey.Free;
  prng.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.