/*

 * Copyright (c) 2002, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package sun.security.validator;

import java.util.Set;

import java.util.HashSet;

import java.util.Collections;

import java.util.Enumeration;

import java.security.KeyStore;

import java.security.KeyStoreException;

import java.security.cert.X509Certificate;

import java.security.cert.Certificate;

/**

 * Collection of static utility methods related to trust anchor KeyStores.

 *

 * @author Andreas Sterbenz

 */

public final class TrustStoreUtil {

    private TrustStoreUtil() {

        // empty

    }

    /**

     * Return an unmodifiable Set with all trusted X509Certificates contained

     * in the specified KeyStore.

     */

    public static Set<X509Certificate> getTrustedCerts(KeyStore ks) {

        Set<X509Certificate> set = new HashSet<>();

        try {

            for (Enumeration<String> e = ks.aliases(); e.hasMoreElements(); ) {

                String alias = e.nextElement();

                if (ks.isCertificateEntry(alias)) {

                    Certificate cert = ks.getCertificate(alias);

                    if (cert instanceof X509Certificate) {

                        set.add((X509Certificate)cert);

                    }

                } else if (ks.isKeyEntry(alias)) {

                    Certificate[] certs = ks.getCertificateChain(alias);

                    if ((certs != null) && (certs.length > 0) &&

                            (certs[0] instanceof X509Certificate)) {

                        set.add((X509Certificate)certs[0]);

                    }

                }

            }

        } catch (KeyStoreException e) {

            // ignore

            //

            // This should be rare, but better to log this in the future.

        }

        return Collections.unmodifiableSet(set);

    }

}