/*

 * Copyright (c) 1999, 2007, 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.pkcs12;

import java.io.*;

import java.security.*;

import sun.security.util.DerInputStream;

import sun.security.util.DerOutputStream;

import sun.security.util.DerValue;

import sun.security.x509.AlgorithmId;

import sun.security.pkcs.ParsingException;

/**

 * A MacData type, as defined in PKCS#12.

 *

 * @author Sharon Liu

 */

class MacData {

    private String digestAlgorithmName;

    private AlgorithmParameters digestAlgorithmParams;

    private byte[] digest;

    private byte[] macSalt;

    private int iterations;

    // the ASN.1 encoded contents of this class

    private byte[] encoded = null;

    /**

     * Parses a PKCS#12 MAC data.

     */

    MacData(DerInputStream derin)

        throws IOException, ParsingException

    {

        DerValue[] macData = derin.getSequence(2);

        // Parse the digest info

        DerInputStream digestIn = new DerInputStream(macData[0].toByteArray());

        DerValue[] digestInfo = digestIn.getSequence(2);

        // Parse the DigestAlgorithmIdentifier.

        AlgorithmId digestAlgorithmId = AlgorithmId.parse(digestInfo[0]);

        this.digestAlgorithmName = digestAlgorithmId.getName();

        this.digestAlgorithmParams = digestAlgorithmId.getParameters();

        // Get the digest.

        this.digest = digestInfo[1].getOctetString();

        // Get the salt.

        this.macSalt = macData[1].getOctetString();

        // Iterations is optional. The default value is 1.

        if (macData.length > 2) {

            this.iterations = macData[2].getInteger();

        } else {

            this.iterations = 1;

        }

    }

    MacData(String algName, byte[] digest, byte[] salt, int iterations)

        throws NoSuchAlgorithmException

    {

        if (algName == null)

           throw new NullPointerException("the algName parameter " +

                                               "must be non-null");

        AlgorithmId algid = AlgorithmId.get(algName);

        this.digestAlgorithmName = algid.getName();

        this.digestAlgorithmParams = algid.getParameters();

        if (digest == null) {

            throw new NullPointerException("the digest " +

                                           "parameter must be non-null");

        } else if (digest.length == 0) {

            throw new IllegalArgumentException("the digest " +

                                                "parameter must not be empty");

        } else {

            this.digest = digest.clone();

        }

        this.macSalt = salt;

        this.iterations = iterations;

        // delay the generation of ASN.1 encoding until

        // getEncoded() is called

        this.encoded = null;

    }

    MacData(AlgorithmParameters algParams, byte[] digest,

        byte[] salt, int iterations) throws NoSuchAlgorithmException

    {

        if (algParams == null)

           throw new NullPointerException("the algParams parameter " +

                                               "must be non-null");

        AlgorithmId algid = AlgorithmId.get(algParams);

        this.digestAlgorithmName = algid.getName();

        this.digestAlgorithmParams = algid.getParameters();

        if (digest == null) {

            throw new NullPointerException("the digest " +

                                           "parameter must be non-null");

        } else if (digest.length == 0) {

            throw new IllegalArgumentException("the digest " +

                                                "parameter must not be empty");

        } else {

            this.digest = digest.clone();

        }

        this.macSalt = salt;

        this.iterations = iterations;

        // delay the generation of ASN.1 encoding until

        // getEncoded() is called

        this.encoded = null;

    }

    String getDigestAlgName() {

        return digestAlgorithmName;

    }

    byte[] getSalt() {

        return macSalt;

    }

    int getIterations() {

        return iterations;

    }

    byte[] getDigest() {

        return digest;

    }

    /**

     * Returns the ASN.1 encoding of this object.

     * @return the ASN.1 encoding.

     * @exception IOException if error occurs when constructing its

     * ASN.1 encoding.

     */

    public byte[] getEncoded() throws NoSuchAlgorithmException, IOException

    {

        if (this.encoded != null)

            return this.encoded.clone();

        DerOutputStream out = new DerOutputStream();

        DerOutputStream tmp = new DerOutputStream();

        DerOutputStream tmp2 = new DerOutputStream();

        // encode encryption algorithm

        AlgorithmId algid = AlgorithmId.get(digestAlgorithmName);

        algid.encode(tmp2);

        // encode digest data

        tmp2.putOctetString(digest);

        tmp.write(DerValue.tag_Sequence, tmp2);

        // encode salt

        tmp.putOctetString(macSalt);

        // encode iterations

        tmp.putInteger(iterations);

        // wrap everything into a SEQUENCE

        out.write(DerValue.tag_Sequence, tmp);

        this.encoded = out.toByteArray();

        return this.encoded.clone();

    }

}