PHP ActiveX Requires Chilkat v11.0.0+

Validate Certificate using OCSP Protocol

See more Certificates Examples

Demonstrates how to validate a certificate (check the revoked status) using the OCSP protocol. PHP ActiveX

<?php

$success = 0;

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

//  This example will check the revoked status of a certificate loaded from a file.
$cert = new COM("Chilkat.Cert");
$success = $cert->LoadFromFile('qa_data/certs/google.crt');
if ($success == 0) {
    print $cert->LastErrorText . "\n";
    exit;
}

//  Get the cert's OCSP URL.
$ocspUrl = $cert->OcspUrl;

//  Build the JSON that will be the OCSP request.

//  Possible hash algorithms are sha1, sha256, sha384, sha512.  
$hashAlg = 'sha256';
$prng = new COM("Chilkat.Prng");
$json = new COM("Chilkat.JsonObject");
$json->EmitCompact = 0;
//  Read more about OCSP nonce lengths
$json->UpdateString('extensions.ocspNonce',$prng->genRandom(16,'base64'));
$json->I = 0;
$json->UpdateString('request[i].cert.hashAlg',$hashAlg);
$json->UpdateString('request[i].cert.issuerNameHash',$cert->hashOf('IssuerDN',$hashAlg,'base64'));
$json->UpdateString('request[i].cert.issuerKeyHash',$cert->hashOf('IssuerPublicKey',$hashAlg,'base64'));
$json->UpdateString('request[i].cert.serialNumber',$cert->SerialNumber);

print $json->emit() . "\n";

//  Our OCSP request looks something like this:
//  {
//    "extensions": {
//      "ocspNonce": "qZDfbpO+nUxRzz6c/SPjE5QCAsPfpkQlRDxTnGl0gnxt7iXO"
//    },
//    "request": [
//      {
//        "cert": {
//          "hashAlg": "sha1",
//          "issuerNameHash": "9u2wY2IygZo19o11oJ0CShGqbK0=",
//          "issuerKeyHash": "d8K4UJpndnaxLcKG0IOgfqZ+uks=",
//          "serialNumber": "6175535D87BF94B6"
//        }
//      }
//    ]
//  }

$ocspRequest = new COM("Chilkat.BinData");
$http = new COM("Chilkat.Http");

//  Convert our JSON to a binary (ASN.1) OCSP request
$success = $http->CreateOcspRequest($json,$ocspRequest);
if ($success == 0) {
    print $http->LastErrorText . "\n";
    exit;
}

//  Send the OCSP request to the OCSP server
$resp = new COM("Chilkat.HttpResponse");
$success = $http->HttpBd('POST',$ocspUrl,$ocspRequest,'application/ocsp-request',$resp);
if ($success == 0) {
    print $http->LastErrorText . "\n";
    exit;
}

//  Get the binary (ASN.1) OCSP reply
$ocspReply = new COM("Chilkat.BinData");
$resp->GetBodyBd($ocspReply);

//  Convert the binary reply to JSON.
//  Also returns the overall OCSP response status.
$jsonReply = new COM("Chilkat.JsonObject");
$ocspStatus = $http->ParseOcspReply($ocspReply,$jsonReply);

//  The ocspStatus can have one of these values:
//  -1:  The ARG1 does not contain a valid OCSP reply.
//  0:  Successful - Response has valid confirmations..
//  1: Malformed request - Illegal confirmation request.
//  2: Internal error - Internal error in issuer.
//  3: Try later -  Try again later.
//  4: Not used - This value is never returned.
//  5: Sig required - Must sign the request.
//  6: Unauthorized - Request unauthorized.

if ($ocspStatus < 0) {
    print 'Invalid OCSP reply.' . "\n";
    exit;
}

print 'Overall OCSP Response Status: ' . $ocspStatus . "\n";

//  Let's examine the OCSP response (in JSON).
$jsonReply->EmitCompact = 0;
print $jsonReply->emit() . "\n";

//  The JSON reply looks like this:
//  (Use the online tool at https://tools.chilkat.io/jsonParse.cshtml
//  to generate JSON parsing code.)

//  {
//    "responseStatus": 0,
//    "responseTypeOid": "1.3.6.1.5.5.7.48.1.1",
//    "responseTypeName": "ocspBasic",
//    "response": {
//      "responderIdChoice": "KeyHash",
//      "responderKeyHash": "d8K4UJpndnaxLcKG0IOgfqZ+uks=",
//      "dateTime": "20180803193937Z",
//      "cert": [
//        {
//          "hashOid": "1.3.14.3.2.26",
//          "hashAlg": "SHA-1",
//          "issuerNameHash": "9u2wY2IygZo19o11oJ0CShGqbK0=",
//          "issuerKeyHash": "d8K4UJpndnaxLcKG0IOgfqZ+uks=",
//          "serialNumber": "6175535D87BF94B6",
//          "status": 0,
//          "thisUpdate": "20180803193937Z",
//          "nextUpdate": "20180810193937Z"
//        }
//      ]
//    }
//  }
//  

//  The certificate status:
$certStatus = -1;
if ($jsonReply->HasMember('response.cert[0].status') == 1) {
    $certStatus = $jsonReply->IntOf('response.cert[0].status');
}

//  Possible certStatus values are:
//  -1: No status returned.
//  0: Good
//  1: Revoked
//  2: Unknown.
print 'Certificate Status: ' . $certStatus . "\n";

?>