OCSP Revocation on client certificate

Question

How do I manually check for certificate revocation status in java using OCSP, given just a client's java.security.cert.X509Certificate? I can't see a clear way to do it.

Alternatively, can I make tomcat do it for me automatically, and how do you know your solution to be true?

Phail

Answer 1

I found a most excellent solution:

http://www.docjar.com/html/api/sun/security/provider/certpath/OCSP.java.html

        /**
   54    * This is a class that checks the revocation status of a certificate(s) using
   55    * OCSP. It is not a PKIXCertPathChecker and therefore can be used outside of
   56    * the CertPathValidator framework. It is useful when you want to
   57    * just check the revocation status of a certificate, and you don't want to
   58    * incur the overhead of validating all of the certificates in the
   59    * associated certificate chain.
   60    *
   61    * @author Sean Mullan
   62    */

It has a method check(X509Certificate clientCert, X509Certificate issuerCert) that does the trick!

Phail

what is the issuerCert? – Retro

@Phail : I am using the class that you have mentioned. The problem is that it is using a POST to do OCSP check. How can we make a GET call for OCSP check since the above class can not be extended ? – Dmitri

Answer 2

It appears there is a patch for Tomcat here to enable ocsp validation.

If you choose to do it manually:

Security.setProperty("ocsp.enable", "true")

Or set it via a command-line argument. See here:

This property's value is either true or false. If true, OCSP checking is enabled when doing certificate revocation checking; if false or not set, OCSP checking is disabled.

And here's some code that I think works:

interface ValidationStrategy {
    boolean validate(X509Certificate certificate, CertPath certPath,
            PKIXParameters parameters) throws GeneralSecurityException;
}


class SunOCSPValidationStrategy implements ValidationStrategy {
    @Override
    public boolean validate(X509Certificate certificate, CertPath certPath,
            PKIXParameters parameters) throws GeneralSecurityException {
        try {
            CertPathValidator cpv = CertPathValidator.getInstance("PKIX");
            PKIXCertPathValidatorResult result = (PKIXCertPathValidatorResult) cpv
                    .validate(certPath, parameters);
            Signature.LOG.debug("Validation result is: " + result);
            return true; // if no exception is thrown
        } catch (CertPathValidatorException cpve) {

            // if the exception is (or is caused by)
            // CertificateRevokedException, return false;
            // otherwise re-throw, because this indicates a failure to perform
            // the validation
            Throwable cause = ExceptionUtils.getRootCause(cpve);
            Class<? extends Throwable> exceptionClass = cause != null ? cause.getClass()
                    : cpve.getClass();
            if (exceptionClass.getSimpleName().equals("CertificateRevokedException")) {
                return false;
            }
            throw cpve;
        }
    }

}

Glyptodont

and this works for tomcat? I've googled around, and saw this solution, I just don't see that it will definitely work written anywhere. – Phail

@Phail - you'd have to check manually for revoked certificates. – Glyptodont

can I do that without using a CRL? – Phail

nope, I've been playing around with bouncy castle, trying to find the simplest way to do it or an example. – Phail

@Bozho, appreciate your help, but I'm still having some problems. #5238470 – Phail

@Bozho, I ran into some problems creating the certpath, but I found a simpler solution above. – Phail

Answer 3

Here's the relevant code from Jetty 7 that takes an array of certificates pulled from the servletRequest request and validates them via the certpath API with OCSP.

http://grepcode.com/file/repo1.maven.org/maven2/org.eclipse.jetty/jetty-util/7.4.0.v20110414/org/eclipse/jetty/util/security/CertificateValidator.java#189

Phail

Answer 4

import org.bouncycastle.util.io.pem.PemReader;
import sun.security.provider.certpath.OCSP;
import sun.security.x509.X509CertImpl;
import java.io.IOException;
import java.io.StringReader;
import java.net.URI;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.security.cert.CertPathValidatorException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.Date;

public void test() throws IOException, CertPathValidatorException, java.security.cert.CertificateException {
        X509Certificate userCert = getX509Cert("path_to_user_cert");
        X509Certificate caCert = getX509Cert("path_to_CA_cert");
        OCSP.RevocationStatus ocsp = OCSP.check(userCert, caCert, URI.create("URL to OCSP, but this can be read from USER Cert(AuthorityInfoAccess) As well"), caCert, new Date());
        System.out.println(ocsp);
    }

    private X509CertImpl getX509Cert(final String path) throws CertificateException, IOException {
        return new X509CertImpl(
                new PemReader(
                        new StringReader(
                                new String(
                                        Files.readAllBytes(
                                                Paths.get(path)))))
                        .readPemObject()
                        .getContent());
    }

Palmy