PHP

Get Certificate Authority Information Access

See more Certificates Examples

Demonstrates how to get a certificate's Authority Information Access extension data (if it exists).

Note: This example requires Chilkat v9.5.0.76 or greater.

Chilkat2 PHP

<?php

use Chilkat2\Cert;
use Chilkat2\StringBuilder;
use Chilkat2\Xml;

$success = false;

$cert = new Cert();

try {
    $cert->LoadFromFile('qa_data/certs/test_haswdt.cer');
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

// Get the Authority Information Access extension, which is at OID 1.3.6.1.5.5.7.1.1
try {
    $extensionXmlStr = $cert->GetExtensionAsXml('1.3.6.1.5.5.7.1.1');
} catch (\Chilkat2\Exception $e) {
    echo "Certificate does not have the AuthInfoAccess extension.\n";
    exit;
}

$xml = new Xml();
$xml->LoadXml($extensionXmlStr);

// See what we have..
echo $xml->GetXml(), "\n";

// We should get XML like this:

/*
 * <?xml version="1.0" encoding="utf-8" ?>
 * <sequence>
 *     <sequence>
 *         <oid>1.3.6.1.5.5.7.48.2</oid>
 *         <contextSpecific tag="6" constructed="0">aHR0cDovL2NydC5jb21vZG9jYS5jb20vQ09NT0RPUlNBQ2xpZW50QXV0aGVudGljYXRpb25hbmRTZWN1
 * cmVFbWFpbENBLmNydA==</contextSpecific>
 *     </sequence>
 *     <sequence>
 *         <oid>1.3.6.1.5.5.7.48.1</oid>
 *         <contextSpecific tag="6" constructed="0">aHR0cDovL29jc3AuY29tb2RvY2EuY29t</contextSpecific>
 *     </sequence>
 * </sequence>
 */

// Typically, a certificate AIA(Authority Information access) contains 2 parts:
//
//     On-line Certificate Status Protocol (1.3.6.1.5.5.7.48.1)
//     Certification Authority Issuer (1.3.6.1.5.5.7.48.2)
//
// The base64 content for each OID (in this case) is just a string.
// The data can be accessed and decoded like this:

$sbOcsp = new StringBuilder();
try {
    $xml->GetChildContentSb('/C/oid,1.3.6.1.5.5.7.48.1|++', $sbOcsp);
    $success = true;
} catch (\Chilkat2\Exception $e) {
    $success = false;
}
if ($success) {
    $sbOcsp->Decode('base64', 'utf-8');
    echo '1.3.6.1.5.5.7.48.1:  ', $sbOcsp->GetAsString(), "\n";
}

$sbIssuer = new StringBuilder();
try {
    $xml->GetChildContentSb('/C/oid,1.3.6.1.5.5.7.48.2|++', $sbIssuer);
    $success = true;
} catch (\Chilkat2\Exception $e) {
    $success = false;
}
if ($success) {
    $sbIssuer->Decode('base64', 'utf-8');
    echo '1.3.6.1.5.5.7.48.2:  ', $sbIssuer->GetAsString(), "\n";
}

// The output looks like this:

// 1.3.6.1.5.5.7.48.1:  http://ocsp.comodoca.com
// 1.3.6.1.5.5.7.48.2:  http://crt.comodoca.com/COMODORSAClientAuthenticationandSecureEmailCA.crt

// -------------------------------------------------------------------------------
// Note: The Chilkat path passed to GetChildContentSb is composed of two commands:
// The first command is "/C/oid,1.3.6.1.5.5.7.48.1".   It says "traverse the XML tree from the caller
// node and stop at the 1st node having tag = "oid" and content = "1.3.6.1.5.5.7.48.1".
// The "|" char separates the 1st command from the 2nd.
// The 2nd command is "++" and says "move to the next sibling".