/*
 *
 * Copyright (c) 2013 - 2017 Lijun Liao
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 *
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * THE AUTHOR LIJUN LIAO. LIJUN LIAO DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
 * OF THIRD PARTY RIGHTS.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the XiPKI software without
 * disclosing the source code of your own applications.
 *
 * For more information, please contact Lijun Liao at this
 * address: lijun.liao@gmail.com
 */

package org.xipki.pki.scep.client;

import java.security.cert.CertificateEncodingException;
import java.security.cert.X509Certificate;

import org.eclipse.jdt.annotation.NonNull;
import org.xipki.pki.scep.crypto.ScepHashAlgoType;

/**
 * @author Lijun Liao
 * @since 2.0.0
 */

public abstract class FingerprintCertificateValidator implements CaCertValidator {

    private static final ScepHashAlgoType DEFAULT_HASHALGO = ScepHashAlgoType.SHA256;

    private ScepHashAlgoType hashAlgo;

    public ScepHashAlgoType getHashAlgo() {
        return hashAlgo;
    }

    public void setHashAlgo(final ScepHashAlgoType hashAlgo) {
        this.hashAlgo = hashAlgo;
    }

    @Override
    public boolean isTrusted(final X509Certificate cert) {
        ScepHashAlgoType algo = (hashAlgo == null) ? DEFAULT_HASHALGO : hashAlgo;
        byte[] actual;
        try {
            actual = algo.digest(cert.getEncoded());
        } catch (CertificateEncodingException ex) {
            return false;
        }

        return isCertTrusted(algo, actual);
    }

    protected abstract boolean isCertTrusted(@NonNull ScepHashAlgoType hashAlgo,
            @NonNull byte[] hashValue);

}