(Delphi ActiveX) RSA Sign using Base64 Private Key

Signs a string using a non-encrypted RSA private key in base64 encoding. Returns the RSA signature as a base64 string.

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
privKey: TPrivateKey;
success: Integer;
sbPem: TChilkatStringBuilder;
rsa: TChilkatRsa;
strSigned: WideString;
strOriginal: WideString;

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

privKey := TPrivateKey.Create(Self);

sbPem := TChilkatStringBuilder.Create(Self);
sbPem.AppendLine('-----BEGIN RSA PRIVATE KEY-----',1);
sbPem.AppendLine('MIIC .... j5A==',1);
sbPem.AppendLine('-----END RSA PRIVATE KEY-----',1);

success := privKey.LoadPem(sbPem.GetAsString());
if (success <> 1) then
  begin
    Memo1.Lines.Add(privKey.LastErrorText);
    Exit;
  end;

rsa := TChilkatRsa.Create(Self);

success := rsa.ImportPrivateKeyObj(privKey.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rsa.LastErrorText);
    Exit;
  end;

rsa.EncodingMode := 'base64';
strSigned := rsa.OpenSslSignStringENC('12345678');
Memo1.Lines.Add(strSigned);

strOriginal := rsa.OpenSslVerifyStringENC(strSigned);
Memo1.Lines.Add(strOriginal);
end;