Delphi ActiveX

Create PKCS1 RSA Signature with PEM Private Key

See more RSA Examples

Demonstrates how to load a private key from a PEM file and create a PKCS1 RSA digital signature. 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;
pkey: TPrivateKey;
rsa: TChilkatRsa;
strData: WideString;
hexSig: WideString;

begin
success := 0;

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

pkey := TPrivateKey.Create(Self);

// Load the private key from an RSA PEM file:
success := pkey.LoadPemFile('pvkey2_rsa.pem');
if (success = 0) then
  begin
    Memo1.Lines.Add(pkey.LastErrorText);
    Exit;
  end;

rsa := TChilkatRsa.Create(Self);

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

// Get the signature as hex.
rsa.EncodingMode := 'hex';

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

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

Memo1.Lines.Add(hexSig);

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