Pascal (Lazarus/Delphi)

RSA Sign utf-8 Bytes of String to get Base64 RSA Signature

See more Apple Keychain Examples

Demonstrates how RSA sign the utf-8 byte representation of a string to get the signature in base64 format. 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.StringBuilder,
  Chilkat.Rsa,
  Chilkat.Cert;

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

procedure RunDemo;
var
  success: Boolean;
  cert: TCert;
  sb: TStringBuilder;
  crlfLineEnding: Boolean;
  i: Integer;
  rsa: TRsa;
  stringToSign: string;
  sigBase64: string;

begin
  success := False;

  //  Assuming the smartcard/USB token is installed with the correct drivers from the manufacturer,
  //  this code can work on multiple platforms including Windows, MacOS, Linux, and iOS.

  //  Chilkat automatically detects and determines the way in which the HSM is used,
  //  which can be by PKCS11, Apple Keychain, Microsoft CNG / Crypto API, or ScMinidriver.

  cert := TCert.Create;

  //  Set the token/smartcard PIN prior to loading.
  cert.SmartCardPin := '123456';

  //  Specify the certificate by its common name.
  success := cert.LoadFromSmartcard('cn=chilkat-rsa-2048');
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  WriteLn('Signing with cert: ' + cert.SubjectCN);

  //  Create a string to be hashed and signed.
  sb := TStringBuilder.Create;
  crlfLineEnding := True;

  for i := 0 to 10 do
    begin
      sb.AppendLine('This is a test.',crlfLineEnding);
    end;

  rsa := TRsa.Create;

  //  Use the certificate's private key for signing.
  success := rsa.SetX509Cert(cert,True);
  if (success = False) then
    begin
      WriteLn(rsa.LastErrorText);
      Exit;
    end;

  //  Sign the SHA-256 hash of the utf-8 byte representation of the contents of sb
  //  Return the signature in base64 format.
  rsa.EncodingMode := 'base64';
  rsa.Charset := 'utf-8';
  stringToSign := sb.GetAsString();
  sigBase64 := rsa.SignStringENC(stringToSign,'sha256');
  if (rsa.LastMethodSuccess = False) then
    begin
      WriteLn(rsa.LastErrorText);
      Exit;
    end;

  WriteLn('RSA signature as base64: ' + sigBase64);


  cert.Free;
  sb.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.