(Perl) Get Certificate Authority Information Access

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.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

$cert = chilkat::CkCert->new();

$success = $cert->LoadFromFile("qa_data/certs/test_haswdt.cer");
if ($success != 1) {
    print $cert->lastErrorText() . "\r\n";
    exit;
}

#  Get the Authority Information Access extension, which is at OID 1.3.6.1.5.5.7.1.1
$extensionXmlStr = $cert->getExtensionAsXml("1.3.6.1.5.5.7.1.1");
if ($cert->get_LastMethodSuccess() == 0) {
    print "Certificate does not have the AuthInfoAccess extension." . "\r\n";
    exit;
}

$xml = chilkat::CkXml->new();
$xml->LoadXml($extensionXmlStr);

#  See what we have..
print $xml->getXml() . "\r\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 = chilkat::CkStringBuilder->new();
$success = $xml->GetChildContentSb("/C/oid,1.3.6.1.5.5.7.48.1|++",$sbOcsp);
if ($success == 1) {
    $sbOcsp->Decode("base64","utf-8");
    print "1.3.6.1.5.5.7.48.1:  " . $sbOcsp->getAsString() . "\r\n";
}

$sbIssuer = chilkat::CkStringBuilder->new();
$success = $xml->GetChildContentSb("/C/oid,1.3.6.1.5.5.7.48.2|++",$sbIssuer);
if ($success == 1) {
    $sbIssuer->Decode("base64","utf-8");
    print "1.3.6.1.5.5.7.48.2:  " . $sbIssuer->getAsString() . "\r\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".