(Delphi DLL) RSA Encrypt and OpenSSL Decrypt

Demonstrates how to use Chilkat to RSA encrypt, and then use OpenSSL to decrypt.

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

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, BinData, PrivateKey, Rsa, PublicKey;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
rsa: HCkRsa;
privKey: HCkPrivateKey;
pubKey: HCkPublicKey;
plainText: PWideChar;
bUsePrivateKey: Boolean;
encryptedStr: PWideChar;
bd: HCkBinData;

begin
success := False;

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

rsa := CkRsa_Create();

privKey := CkPrivateKey_Create();
success := CkRsa_GenKey(rsa,2048,privKey);
success := CkPrivateKey_SavePkcs8PemFile(privKey,'qa_output/privKey.pem');

pubKey := CkPublicKey_Create();
CkPrivateKey_ToPublicKey(privKey,pubKey);

CkRsa_putEncodingMode(rsa,'base64');
plainText := 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz01234567890';
bUsePrivateKey := False;
CkRsa_UsePublicKey(rsa,pubKey);
encryptedStr := CkRsa__encryptStringENC(rsa,plainText,bUsePrivateKey);

bd := CkBinData_Create();
CkBinData_AppendEncoded(bd,encryptedStr,'base64');
success := CkBinData_WriteFile(bd,'qa_output/enc.dat');

// The OpenSSL command to decrypt is:
// openssl pkeyutl -in enc.dat -inkey privKey.pem -keyform PEM -pkeyopt rsa_padding_mode:pkcs1 -decrypt

Memo1.Lines.Add('OK');

CkRsa_Dispose(rsa);
CkPrivateKey_Dispose(privKey);
CkPublicKey_Dispose(pubKey);
CkBinData_Dispose(bd);

end;