(C#) Download and Trust the DigiCert Global Root CA

Demonstrates how to download a root certificate and trust it.

For more information, see https://www.digicert.com/digicert-root-certificates.htm

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

// In this example, the URLs for the DigiCert root CA certs are available at this web page:
// https://www.digicert.com/digicert-root-certificates.htm

// This example downloads the "DigiCert Global Root G3"
// Valid until: 15/Jan/2038
// Serial #: 05:55:56:BC:F2:5E:A4:35:35:C3:A4:0F:D5:AB:45:72
// Thumbprint: 7E04DE896A3E666D00E687D33FFAD93BE83D349E

string certUrl = "https://dl.cacerts.digicert.com/DigiCertGlobalRootG3.crt";

Chilkat.Http http = new Chilkat.Http();
Chilkat.BinData bdCert = new Chilkat.BinData();
bool success = http.DownloadBd(certUrl,bdCert);
if (success == false) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

// Load it into a Chilkat cert object.
Chilkat.Cert cert = new Chilkat.Cert();
success = cert.LoadFromBd(bdCert);
if (success == false) {
    Debug.WriteLine(cert.LastErrorText);
    return;
}

// Examine the common name,serial, and thumbprint:
Debug.WriteLine("CN: " + cert.SubjectCN);
Debug.WriteLine("Serial: " + cert.SerialNumber);
Debug.WriteLine("Thumbprint: " + cert.Sha1Thumbprint);

// Output from the above:
// CN: DigiCert Global Root G3
// Serial: 055556BCF25EA43535C3A40FD5AB4572
// Thumbprint: 7E04DE896A3E666D00E687D33FFAD93BE83D349E

// If desired, the certificate can be saved to a local file so it does not need
// to be downloaded from the website every time.  
string certPath = "qa_data/certs/DigiCertGlobalRootG3.crt";
success = bdCert.WriteFile(certPath);

// To load the cert from a file...
success = cert.LoadFromFile(certPath);

// Do the following to add the cert to the collection of trusted roots
// for this application.  (Note:  The trust is not persisted.  Each time the
// application runs, it should load the cert (from whatever source, whether it is
// a file, a database,etc.) and do the following:
Chilkat.TrustedRoots troots = new Chilkat.TrustedRoots();

troots.AddCert(cert);
troots.Activate();

Debug.WriteLine(cert.SubjectCN + " is now trusted for this run of this application.");