(Delphi ActiveX) RSA Encrypt with Modulus and Exponent

Demonstrates how to RSA encrypt with a given modulus and exponent.

Note: This example requires Chilkat v11.0.0 or greater.

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
success: Integer;
rsa: TChilkatRsa;
modulus: WideString;
exponent: WideString;
xml: TChilkatXml;
pubKey: TPublicKey;
usePrivateKey: Integer;
plainText: WideString;
encryptedStrBase64: 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);

// Assuming you already have a base64 modulus and exponent,
// wrap it in XML like this:
modulus := 'qMBRpdYrAy5aMmo31NErUizh5sbweguSmh4wlK6uJEIDl+kwTlROnE34KOFExeTbJSX0WygPi+vWl0yNq7buIMUKpytossAAWut5khO3CQJxTk7G2gnEPNUUXHiExGgNrLzcSLv8YIlfVALhoRWyC67KOL+a+3taNq3h+BHeWhM=';
exponent := 'AQAB';

xml := TChilkatXml.Create(Self);
xml.Tag := 'RSAPublicKey';
xml.NewChild2('Modulus',modulus);
xml.NewChild2('Exponent',exponent);

pubKey := TPublicKey.Create(Self);
success := pubKey.LoadFromString(xml.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pubKey.LastErrorText);
    Exit;
  end;

success := rsa.UsePublicKey(pubKey.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(rsa.LastErrorText);
    Exit;
  end;

usePrivateKey := 0;
plainText := 'message in a bottle';

rsa.EncodingMode := 'base64';
encryptedStrBase64 := rsa.EncryptStringENC(plainText,usePrivateKey);
Memo1.Lines.Add(encryptedStrBase64);
end;