(PHP Extension) 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.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

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

$http = new CkHttp();

// We're getting the SSL/TLS certificate, so make sure to connect to the SSL/TLS port (443).
// sslCert is a CkCert
$sslCert = $http->GetServerSslCert('nationalgeographic.com',443);
if ($http->get_LastMethodSuccess() == false) {
    print $http->lastErrorText() . "\n";
    exit;
}

// 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.
// certChain is a CkCertChain
$certChain = $sslCert->GetCertChain();
if ($sslCert->get_LastMethodSuccess() == false) {
    print $sslCert->lastErrorText() . "\n";

    exit;
}

$i = 0;
$numCerts = $certChain->get_NumCerts();
while ($i < $numCerts) {
    // cert is a CkCert
    $cert = $certChain->GetCert($i);
    print 'SubjectDN ' . $i . ': ' . $cert->subjectDN() . "\n";
    print 'IssuerDN ' . $i . ': ' . $cert->issuerDN() . "\n";

    $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) {
    // caCert is a CkCert
    $caCert = $certChain->GetCert($numCerts - 1);
    print 'CA Root Cert: ' . $caCert->subjectDN() . "\n";

}


?>