(C++) Get the Server Certificate, Certificate Chain, and Root CA Certificate

Demonstrates how to get the HTTP server certificate, its certificate chain, and the root CA certificate.

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#include <CkHttp.h>
#include <CkCert.h>
#include <CkCertChain.h>

void ChilkatSample(void)
    {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkHttp http;

    // We're getting the SSL/TLS certificate, so make sure to connect to the SSL/TLS port (443).
    CkCert *sslCert = http.GetServerSslCert("nationalgeographic.com",443);
    if (http.get_LastMethodSuccess() == false) {
        std::cout << http.lastErrorText() << "\r\n";
        return;
    }

    // Note: Prior to v9.5.0.50, this method would fail if the certificate chain could not 
    // be completed to the root.  Starting in v9.5.0.50, the incomplete certificate chain 
    // will be returned.  The certificate chain's ReachesRoot property can be examined to 
    // see if the chain was completed to the root.
    CkCertChain *certChain = sslCert->GetCertChain();
    if (sslCert->get_LastMethodSuccess() == false) {
        std::cout << sslCert->lastErrorText() << "\r\n";
        delete sslCert;
        return;
    }

    int i = 0;
    int numCerts = certChain->get_NumCerts();
    while (i < numCerts) {
        CkCert *cert = certChain->GetCert(i);
        std::cout << "SubjectDN " << i << ": " << cert->subjectDN() << "\r\n";
        std::cout << "IssuerDN " << i << ": " << cert->issuerDN() << "\r\n";
        delete cert;
        i = i + 1;
    }

    // If the certificate chain reaches the root CA cert, then the last cert in the chain
    // is the root CA cert.
    if (certChain->get_ReachesRoot() == true) {
        CkCert *caCert = certChain->GetCert(numCerts - 1);
        std::cout << "CA Root Cert: " << caCert->subjectDN() << "\r\n";
        delete caCert;
    }

    delete sslCert;
    delete certChain;
    }