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 * 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.tools.jarsigner;

import java.io.IOException;

import java.net.URI;

import java.security.NoSuchAlgorithmException;

import java.security.cert.CertificateException;

import java.security.cert.X509Certificate;

import com.sun.jarsigner.*;

import sun.security.pkcs.PKCS7;

import sun.security.util.*;

import sun.security.x509.*;

/**

 * This class implements a content signing service.

 * It generates a timestamped signature for a given content according to

 * <a href="http://www.ietf.org/rfc/rfc3161.txt">RFC 3161</a>.

 * The signature along with a trusted timestamp and the signer's certificate

 * are all packaged into a standard PKCS #7 Signed Data message.

 *

 * @author Vincent Ryan

 */

public final class TimestampedSigner extends ContentSigner {

    /*

     * Object identifier for the subject information access X.509 certificate

     * extension.

     */

    private static final String SUBJECT_INFO_ACCESS_OID = "1.3.6.1.5.5.7.1.11";

    /*

     * Object identifier for the timestamping access descriptors.

     */

    private static final ObjectIdentifier AD_TIMESTAMPING_Id;

    static {

        ObjectIdentifier tmp = null;

        try {

            tmp = new ObjectIdentifier("1.3.6.1.5.5.7.48.3");

        } catch (IOException e) {

            // ignore

        }

        AD_TIMESTAMPING_Id = tmp;

    }

    /**

     * Instantiates a content signer that supports timestamped signatures.

     */

    public TimestampedSigner() {

    }

    /**

     * Generates a PKCS #7 signed data message that includes a signature

     * timestamp.

     * This method is used when a signature has already been generated.

     * The signature, a signature timestamp, the signer's certificate chain,

     * and optionally the content that was signed, are packaged into a PKCS #7

     * signed data message.

     *

     * @param params The non-null input parameters.

     * @param omitContent true if the content should be omitted from the

     *        signed data message. Otherwise the content is included.

     * @param applyTimestamp true if the signature should be timestamped.

     *        Otherwise timestamping is not performed.

     * @return A PKCS #7 signed data message including a signature timestamp.

     * @throws NoSuchAlgorithmException The exception is thrown if the signature

     *         algorithm is unrecognised.

     * @throws CertificateException The exception is thrown if an error occurs

     *         while processing the signer's certificate or the TSA's

     *         certificate.

     * @throws IOException The exception is thrown if an error occurs while

     *         generating the signature timestamp or while generating the signed

     *         data message.

     * @throws NullPointerException The exception is thrown if parameters is

     *         null.

     */

    public byte[] generateSignedData(ContentSignerParameters params,

        boolean omitContent, boolean applyTimestamp)

            throws NoSuchAlgorithmException, CertificateException, IOException {

        if (params == null) {

            throw new NullPointerException();

        }

        // Parse the signature algorithm to extract the digest

        // algorithm. The expected format is:

        //     "<digest>with<encryption>"

        // or  "<digest>with<encryption>and<mgf>"

        String signatureAlgorithm = params.getSignatureAlgorithm();

        X509Certificate[] signerChain = params.getSignerCertificateChain();

        byte[] signature = params.getSignature();

        // Include or exclude content

        byte[] content = (omitContent == true) ? null : params.getContent();

        URI tsaURI = null;

        if (applyTimestamp) {

            tsaURI = params.getTimestampingAuthority();

            if (tsaURI == null) {

                // Examine TSA cert

                tsaURI = getTimestampingURI(

                    params.getTimestampingAuthorityCertificate());

                if (tsaURI == null) {

                    throw new CertificateException(

                        "Subject Information Access extension not found");

                }

            }

        }

        String tSADigestAlg = "SHA-256";

        if (params instanceof JarSignerParameters) {

            tSADigestAlg = ((JarSignerParameters)params).getTSADigestAlg();

        }

        return PKCS7.generateSignedData(signature, signerChain, content,

                                        params.getSignatureAlgorithm(), tsaURI,

                                        params.getTSAPolicyID(),

                                        tSADigestAlg);

    }

    /**

     * Examine the certificate for a Subject Information Access extension

     * (<a href="http://tools.ietf.org/html/rfc5280">RFC 5280</a>).

     * The extension's {@code accessMethod} field should contain the object

     * identifier defined for timestamping: 1.3.6.1.5.5.7.48.3 and its

     * {@code accessLocation} field should contain an HTTP or HTTPS URL.

     *

     * @param tsaCertificate An X.509 certificate for the TSA.

     * @return An HTTP or HTTPS URI or null if none was found.

     */

    public static URI getTimestampingURI(X509Certificate tsaCertificate) {

        if (tsaCertificate == null) {

            return null;

        }

        // Parse the extensions

        try {

            byte[] extensionValue =

                tsaCertificate.getExtensionValue(SUBJECT_INFO_ACCESS_OID);

            if (extensionValue == null) {

                return null;

            }

            DerInputStream der = new DerInputStream(extensionValue);

            der = new DerInputStream(der.getOctetString());

            DerValue[] derValue = der.getSequence(5);

            AccessDescription description;

            GeneralName location;

            URIName uri;

            for (int i = 0; i < derValue.length; i++) {

                description = new AccessDescription(derValue[i]);

                if (description.getAccessMethod()

                        .equals((Object)AD_TIMESTAMPING_Id)) {

                    location = description.getAccessLocation();

                    if (location.getType() == GeneralNameInterface.NAME_URI) {

                        uri = (URIName) location.getName();

                        if (uri.getScheme().equalsIgnoreCase("http") ||

                                uri.getScheme().equalsIgnoreCase("https")) {

                            return uri.getURI();

                        }

                    }

                }

            }

        } catch (IOException ioe) {

            // ignore

        }

        return null;

    }

}