Pascal (Lazarus/Delphi)

RSASSA-PSS Algorithm with SHA256 Hashing

See more RSA Examples

RSA encrypt a SHA256 hash with OAEP padding. 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.PrivateKey,
  Chilkat.Rsa;

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

procedure RunDemo;
var
  success: Boolean;
  privkey: TPrivateKey;
  rsa: TRsa;
  sigStr: string;

begin
  success := False;

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

  privkey := TPrivateKey.Create;

  //  Load the private key object from a PEM file.
  //  (To load from a PEM string, call LoadPem instead.)
  success := privkey.LoadPemFile('somePath/myPrivateKey.pem');
  if (success = False) then
    begin
      WriteLn(privkey.LastErrorText);
      Exit;
    end;

  rsa := TRsa.Create;
  //  Use RSA-PSS by setting PkcsPadding = False
  rsa.PkcsPadding := False;
  //  Use SHA256
  rsa.OaepHash := 'SHA-256';

  rsa.UsePrivateKey(privkey);

  //  Generate a base64 signature.
  rsa.EncodingMode := 'base64';

  sigStr := rsa.SignStringENC('String to be signed','SHA-256');
  if (rsa.LastMethodSuccess = False) then
    begin
      WriteLn(rsa.LastErrorText);
      Exit;
    end;

  WriteLn('Signature: ' + sigStr);


  privkey.Free;
  rsa.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.