(Delphi DLL) Renew a DigiCert Certificate from an EST-enabled profile

Demonstrates how to renew a certificate from an EST-enabled profile in DigiCert​​®​​ Trust Lifecycle Manager. (The certificate must be within the renewal window configured in the certificate profile. The CSR must have same Subject DN values as the original certificate.)

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, Csr, HttpResponse, BinData, PrivateKey, Cert, Prng, Http, Ecc;

...

procedure TForm1.Button1Click(Sender: TObject);
var
fortuna: HCkPrng;
entropy: PWideChar;
success: Boolean;
ec: HCkEcc;
privKey: HCkPrivateKey;
csr: HCkCsr;
bdCsr: HCkBinData;
http: HCkHttp;
tlsClientCert: HCkCert;
bdTlsClientCertPrivKey: HCkBinData;
tlsClientCertPrivKey: HCkPrivateKey;
resp: HCkHttpResponse;
myNewCert: HCkCert;

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

// The example below duplicates the following OpenSSL commands:
// 
// # Name of certificate as argument 1
// 
// # Make new key
// openssl ecparam -name prime256v1 -genkey -noout -out ${1}.key.pem
// 
// # Make csr
// openssl req -new -sha256 -key ${1}.key.pem -out ${1}.p10.csr -subj "/CN=${1}"
// 
// # Request new cert
// curl -v --cacert data/ca.pem --cert data/${1}.pem --key data/${1}.key.pem 
//     --data-binary @${1}.p10.csr -o ${1}.p7.b64 -H "Content-Type: application/pkcs10" https://clientauth.demo.one.digicert.com/.well-known/est/IOT/simplereenroll
// 
// # Convert to PEM
// openssl base64 -d -in ${1}.p7.b64 | openssl pkcs7 -inform DER -outform PEM -print_certs -out ${1}.pem

// ------------------------------------------------------------------------------------------------------------------

// Create a Fortuna PRNG and seed it with system entropy.
// This will be our source of random data for generating the ECC private key.
fortuna := CkPrng_Create();
entropy := CkPrng__getEntropy(fortuna,32,'base64');
success := CkPrng_AddEntropy(fortuna,entropy,'base64');

ec := CkEcc_Create();

// Generate a random EC private key on the prime256v1 curve.
privKey := CkEcc_GenEccKey(ec,'prime256v1',fortuna);
if (CkEcc_getLastMethodSuccess(ec) <> True) then
  begin
    Memo1.Lines.Add(CkEcc__lastErrorText(ec));
    Exit;
  end;

// Create the CSR object and set properties.
csr := CkCsr_Create();

// Specify your CN
CkCsr_putCommonName(csr,'mysubdomain.mydomain.com');

// Create the CSR using the private key.
bdCsr := CkBinData_Create();
success := CkCsr_GenCsrBd(csr,privKey,bdCsr);
if (success = False) then
  begin
    Memo1.Lines.Add(CkCsr__lastErrorText(csr));
    CkPrivateKey_Dispose(privKey);
    Exit;
  end;

// Save the private key and CSR to files.
CkPrivateKey_SavePkcs8EncryptedPemFile(privKey,'password','c:/temp/qa_output/ec_privkey.pem');
CkPrivateKey_Dispose(privKey);
CkBinData_WriteFile(bdCsr,'c:/temp/qa_output/csr.pem');

// ----------------------------------------------------------------------
// Now do the CURL request to POST the CSR and get the new certificate.

http := CkHttp_Create();

tlsClientCert := CkCert_Create();
success := CkCert_LoadFromFile(tlsClientCert,'data/myTlsClientCert.pem');
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(tlsClientCert));
    Exit;
  end;

bdTlsClientCertPrivKey := CkBinData_Create();
success := CkBinData_LoadFile(bdTlsClientCertPrivKey,'data/myTlsClientCert.key.pem');
if (success = False) then
  begin
    Memo1.Lines.Add('Failed to load data/myTlsClientCert.key.pem');
    Exit;
  end;

tlsClientCertPrivKey := CkPrivateKey_Create();
success := CkPrivateKey_LoadAnyFormat(tlsClientCertPrivKey,bdTlsClientCertPrivKey,'');
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(tlsClientCertPrivKey));
    Exit;
  end;

success := CkCert_SetPrivateKey(tlsClientCert,tlsClientCertPrivKey);
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(tlsClientCert));
    Exit;
  end;

CkHttp_SetSslClientCert(http,tlsClientCert);

CkHttp_putRequireSslCertVerify(http,True);

// The body of the HTTP request contains the binary CSR.
resp := CkHttp_PBinaryBd(http,'POST','https://clientauth.demo.one.digicert.com/.well-known/est/IOT/simplereenroll',bdCsr,'application/pkcs10',False,False);
if (CkHttp_getLastMethodSuccess(http) = False) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

if (CkHttpResponse_getStatusCode(resp) <> 200) then
  begin
    Memo1.Lines.Add('response status code = ' + IntToStr(CkHttpResponse_getStatusCode(resp)));
    Memo1.Lines.Add(CkHttpResponse__bodyStr(resp));
    Memo1.Lines.Add('Failed');
    CkHttpResponse_Dispose(resp);
    Exit;
  end;

// The response is the Base64 DER of the new certificate.
myNewCert := CkCert_Create();
success := CkCert_LoadFromBase64(myNewCert,CkHttpResponse__bodyStr(resp));
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(myNewCert));
    Memo1.Lines.Add('Cert data = ' + CkHttpResponse__bodyStr(resp));
    Memo1.Lines.Add('Failed.');
    CkHttpResponse_Dispose(resp);
    Exit;
  end;

CkHttpResponse_Dispose(resp);
success := CkCert_SaveToFile(myNewCert,'c:/temp/qa_output/myNewCert.cer');
if (success = False) then
  begin
    Memo1.Lines.Add(CkCert__lastErrorText(myNewCert));
    Memo1.Lines.Add('Failed.');
    Exit;
  end;

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

CkPrng_Dispose(fortuna);
CkEcc_Dispose(ec);
CkCsr_Dispose(csr);
CkBinData_Dispose(bdCsr);
CkHttp_Dispose(http);
CkCert_Dispose(tlsClientCert);
CkBinData_Dispose(bdTlsClientCertPrivKey);
CkPrivateKey_Dispose(tlsClientCertPrivKey);
CkCert_Dispose(myNewCert);

end;