(Delphi DLL) Export a Certificate's Private Key to Various Formats

Loads a digital certificate and private key from a PFX file (also known as PKCS#12) and exports the private key to various formats: (1) PKCS8 Encrypted, (2) PKCS8 Encrypted PEM, (3) PKCS8 unencrypted, (4) PKCS8 PEM unencrypted, (5) RSA DER unencrypted, (6) RSA PEM unencrypted, (7) XML.

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, Cert, PrivateKey;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
cert: HCkCert;
pfxFilename: PWideChar;
pfxPassword: PWideChar;
privKey: HCkPrivateKey;
password: PWideChar;
path: PWideChar;

begin
success := False;

cert := CkCert_Create();

// Load from the PFX file
pfxFilename := '/Users/chilkat/testData/pfx/chilkat_ssl_pwd_is_test.pfx';
pfxPassword := 'test';

// A PFX typically contains certificates in the chain of authentication.
// The Chilkat cert object will choose the certificate w/
// private key farthest from the root authority cert.
// To access all the certificates in a PFX, use the 
// Chilkat certificate store object instead.
success := CkCert_LoadPfxFile(cert,pfxFilename,pfxPassword);
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

// Get the private key...
privKey := CkPrivateKey_Create();
success := CkCert_GetPrivateKey(cert,privKey);
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(cert));
    Exit;
  end;

// Export to various formats:

password := 'secret';

// PKCS8 Encrypted DER
path := '/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.der';
success := CkPrivateKey_SavePkcs8EncryptedFile(privKey,password,path);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

// PKCS8 Encrypted PEM
path := '/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.pem';
success := CkPrivateKey_SavePkcs8EncryptedPemFile(privKey,password,path);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

// PKCS8 Unencrypted DER
path := '/Users/chilkat/testData/privkeys/chilkat_pkcs8.der';
success := CkPrivateKey_SavePkcs8File(privKey,path);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

// PKCS8 Unencrypted PEM
path := '/Users/chilkat/testData/privkeys/chilkat_pkcs8.pem';
success := CkPrivateKey_SavePkcs8PemFile(privKey,path);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

//  RSA DER (unencrypted)
path := '/Users/chilkat/testData/privkeys/chilkat_rsa.der';
success := CkPrivateKey_SavePkcs1File(privKey,path);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

// RSA PEM (unencrypted)
path := '/Users/chilkat/testData/privkeys/chilkat_rsa.pem';
success := CkPrivateKey_SavePemFile(privKey,path);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

// XML (unencrypted)
path := '/Users/chilkat/testData/privkeys/chilkat.xml';
success := CkPrivateKey_SaveXmlFile(privKey,path);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

Memo1.Lines.Add('Private key exported to various formats.');

CkCert_Dispose(cert);
CkPrivateKey_Dispose(privKey);

end;