/*

 * Copyright (c) 2003, 2013, 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

 * or visit www.oracle.com if you need additional information or have any

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 */

package sun.security.timestamp;

import java.io.IOException;

import java.math.BigInteger;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

import java.security.cert.X509Extension;

import sun.security.util.DerValue;

import sun.security.util.DerOutputStream;

import sun.security.util.ObjectIdentifier;

import sun.security.x509.AlgorithmId;

/**

 * This class provides a timestamp request, as defined in

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

 *

 * The TimeStampReq ASN.1 type has the following definition:

 * <pre>

 *

 *     TimeStampReq ::= SEQUENCE {

 *         version           INTEGER { v1(1) },

 *         messageImprint    MessageImprint

 *           -- a hash algorithm OID and the hash value of the data to be

 *           -- time-stamped.

 *         reqPolicy         TSAPolicyId    OPTIONAL,

 *         nonce             INTEGER        OPTIONAL,

 *         certReq           BOOLEAN        DEFAULT FALSE,

 *         extensions        [0] IMPLICIT Extensions OPTIONAL }

 *

 *     MessageImprint ::= SEQUENCE {

 *         hashAlgorithm     AlgorithmIdentifier,

 *         hashedMessage     OCTET STRING }

 *

 *     TSAPolicyId ::= OBJECT IDENTIFIER

 *

 * </pre>

 *

 * @since 1.5

 * @author Vincent Ryan

 * @see Timestamper

 */

public class TSRequest {

    private int version = 1;

    private AlgorithmId hashAlgorithmId = null;

    private byte[] hashValue;

    private String policyId = null;

    private BigInteger nonce = null;

    private boolean returnCertificate = false;

    private X509Extension[] extensions = null;

    /**

     * Constructs a timestamp request for the supplied data.

     *

     * @param toBeTimeStamped  The data to be timestamped.

     * @param messageDigest The MessageDigest of the hash algorithm to use.

     * @throws NoSuchAlgorithmException if the hash algorithm is not supported

     */

    public TSRequest(String tSAPolicyID, byte[] toBeTimeStamped, MessageDigest messageDigest)

        throws NoSuchAlgorithmException {

        this.policyId = tSAPolicyID;

        this.hashAlgorithmId = AlgorithmId.get(messageDigest.getAlgorithm());

        this.hashValue = messageDigest.digest(toBeTimeStamped);

    }

    public byte[] getHashedMessage() {

        return hashValue.clone();

    }

    /**

     * Sets the Time-Stamp Protocol version.

     *

     * @param version The TSP version.

     */

    public void setVersion(int version) {

        this.version = version;

    }

    /**

     * Sets an object identifier for the Time-Stamp Protocol policy.

     *

     * @param version The policy object identifier.

     */

    public void setPolicyId(String policyId) {

        this.policyId = policyId;

    }

    /**

     * Sets a nonce.

     * A nonce is a single-use random number.

     *

     * @param nonce The nonce value.

     */

    public void setNonce(BigInteger nonce) {

        this.nonce = nonce;

    }

    /**

     * Request that the TSA include its signing certificate in the response.

     *

     * @param returnCertificate True if the TSA should return its signing

     *                          certificate. By default it is not returned.

     */

    public void requestCertificate(boolean returnCertificate) {

        this.returnCertificate = returnCertificate;

    }

    /**

     * Sets the Time-Stamp Protocol extensions.

     *

     * @param extensions The protocol extensions.

     */

    public void setExtensions(X509Extension[] extensions) {

        this.extensions = extensions;

    }

    public byte[] encode() throws IOException {

        DerOutputStream request = new DerOutputStream();

        // encode version

        request.putInteger(version);

        // encode messageImprint

        DerOutputStream messageImprint = new DerOutputStream();

        hashAlgorithmId.encode(messageImprint);

        messageImprint.putOctetString(hashValue);

        request.write(DerValue.tag_Sequence, messageImprint);

        // encode optional elements

        if (policyId != null) {

            request.putOID(new ObjectIdentifier(policyId));

        }

        if (nonce != null) {

            request.putInteger(nonce);

        }

        if (returnCertificate) {

            request.putBoolean(true);

        }

        DerOutputStream out = new DerOutputStream();

        out.write(DerValue.tag_Sequence, request);

        return out.toByteArray();

    }

}