(Delphi ActiveX) Duplicate PHP RSA Encryption

Demonstrates how to duplicate the following PHP function.

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;
rsaMOD: WideString;
rsaEXP: WideString;
bdMod: TChilkatBinData;
bdExp: TChilkatBinData;
xml: TChilkatXml;
pubkey: TPublicKey;
rsa: TChilkatRsa;
plainText: WideString;
cipherText: WideString;

begin
success := 0;

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

// Duplicate the following PHP code:
// 
//    public function encryptRSA($plainText,$rsaMOD,$pubKEY){
//         $rsa  = new RSA();
//         $rsa->setEncryptionMode(RSA::ENCRYPTION_PKCS1);
//         $publicKey = [
//             'e' => new BigInteger($pubKEY,16),
//             'n' => new BigInteger($rsaMOD,16)
//         ];
// 		
//         $rsa->loadKey($publicKey);
//         $ciphertext = $rsa->encrypt($plainText);
//         return bin2hex($ciphertext);
//     }
// 
//     $plainText="key=abcdefghijkmnopq&iv=abcdefghijkmnopq&h=12345678&s=12345678"
//     $rsaMOD="F0946D8F05604809E24B8CFFD30349CEA9E5F4D320BFD9E9AA1B088863F02C43E7997D37A3E27B4F8F359F1744DB6B20A437067C0D325A80660D12FF56A57673"
//     $pubKEY="010001"

// We have the RSA modulus in hex
rsaMOD := 'F0946D8F05604809E24B8CFFD30349CEA9E5F4D320BFD9E9AA1B088863F02C43E7997D37A3E27B4F8F359F1744DB6B20A437067C0D325A80660D12FF56A57673';

// The RSA exponent in hex is "010001", which is 65537 in decimal.  It's typically the exponent that is always used.
rsaEXP := '010001';

// Get the RSA modulus and exponent in base64.
bdMod := TChilkatBinData.Create(Self);
bdExp := TChilkatBinData.Create(Self);
success := bdMod.AppendEncoded(rsaMOD,'hex');
success := bdExp.AppendEncoded(rsaEXP,'hex');

// Build the XML representation of the RSA public key
xml := TChilkatXml.Create(Self);
xml.Tag := 'RSAPublicKey';
xml.UpdateChildContent('Modulus',bdMod.GetEncoded('base64'));
xml.UpdateChildContent('Exponent',bdExp.GetEncoded('base64'));

// Load the RSA public key into a Chilkat public key object.
pubkey := TPublicKey.Create(Self);
success := pubkey.LoadFromString(xml.GetXml());

// Setup the RSA object for encryption and do it..
rsa := TChilkatRsa.Create(Self);
rsa.VerboseLogging := 1;
success := rsa.UsePublicKey(pubkey.ControlInterface);

// Use PKCSv1.5 padding
rsa.PkcsPadding := 0;

// Encrypt and return the string as hex.
rsa.EncodingMode := 'hex';
plainText := 'key=abcdefghijkmnopq&iv=abcdefghijkmnopq&h=12345678&s=12345678';
cipherText := rsa.EncryptStringENC(plainText,0);
if (rsa.LastMethodSuccess = 0) then
  begin
    Memo1.Lines.Add(rsa.LastErrorText);
    Exit;
  end;

// Note: The PKCSv1_5 padding incorporates random bytes.  Therefore, the RSA encryption will produce different results each time -- all of which are valid 
// and decrypt correctly to the same original text.
Memo1.Lines.Add(cipherText);
end;