(Delphi DLL) 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.

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

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
rsa: HCkRsa;
pfx: HCkPfx;
success: Boolean;
privKey: HCkPrivateKey;
strData: PWideChar;
base64Sig: PWideChar;

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

rsa := CkRsa_Create();

// Load the .pfx/.p12
pfx := CkPfx_Create();
success := CkPfx_LoadPfxFile(pfx,'qa_data/pfx/myKey.p12','myPassword');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkPfx__lastErrorText(pfx));
    Exit;
  end;

// Get the default private key.
privKey := CkPfx_GetPrivateKey(pfx,0);
if (CkPfx_getLastMethodSuccess(pfx) <> True) then
  begin
    Memo1.Lines.Add(CkPfx__lastErrorText(pfx));
    Exit;
  end;

// Import the private key into the RSA component:
success := CkRsa_ImportPrivateKeyObj(rsa,privKey);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkRsa__lastErrorText(rsa));
    CkPrivateKey_Dispose(privKey);
    Exit;
  end;

CkPrivateKey_Dispose(privKey);

// Get the signature in base64
CkRsa_putEncodingMode(rsa,'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 := CkRsa__signStringENC(rsa,strData,'sha256');

Memo1.Lines.Add(base64Sig);

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

CkRsa_Dispose(rsa);
CkPfx_Dispose(pfx);

end;