Delphi ActiveX

RSA Sign Using Private Key from .pfx/.p12 to Base64 Signature

See more RSA Examples

Demonstrates how to RSA sign something using a private key loaded from a .pfx/.p12. The RSA signature is returned in Base64 encoded format. Delphi ActiveX

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
success: Integer;
rsa: TChilkatRsa;
pfx: TChilkatPfx;
privKey: TPrivateKey;
strData: WideString;
base64Sig: WideString;

begin
success := 0;

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

rsa := TChilkatRsa.Create(Self);

// Load the .pfx/.p12
pfx := TChilkatPfx.Create(Self);
success := pfx.LoadPfxFile('qa_data/pfx/myKey.p12','myPassword');
if (success = 0) then
  begin
    Memo1.Lines.Add(pfx.LastErrorText);
    Exit;
  end;

// Get the default private key.

privKey := TPrivateKey.Create(Self);
success := pfx.PrivateKeyAt(0,privKey.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pfx.LastErrorText);
    Exit;
  end;

// Import the private key into the RSA component:
success := rsa.UsePrivateKey(privKey.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(rsa.LastErrorText);
    Exit;
  end;

// Get the signature in base64
rsa.EncodingMode := 'base64';

strData := 'This is the string to be signed.';

// Sign the string using the sha256 hash algorithm.
// Other valid choices are "sha384", "sha512", "sha-1", "md2" and "md5".
base64Sig := rsa.SignStringENC(strData,'sha256');

Memo1.Lines.Add(base64Sig);

Memo1.Lines.Add('Success!');
end;