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

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 * 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.

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 * 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,

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 *

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

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package sun.security.rsa;

import java.io.IOException;

import java.math.BigInteger;

import java.security.*;

import java.security.spec.AlgorithmParameterSpec;

import java.security.interfaces.*;

import java.util.Arrays;

import sun.security.util.*;

import sun.security.pkcs.PKCS8Key;

import sun.security.rsa.RSAUtil.KeyType;

/**

 * RSA private key implementation for "RSA", "RSASSA-PSS" algorithms in non-CRT

 * form (modulus, private exponent only). For CRT private keys, see

 * RSAPrivateCrtKeyImpl. We need separate classes to ensure correct behavior

 * in instanceof checks, etc.

 *

 * Note: RSA keys must be at least 512 bits long

 *

 * @see RSAPrivateCrtKeyImpl

 * @see RSAKeyFactory

 *

 * @since   1.5

 * @author  Andreas Sterbenz

 */

public final class RSAPrivateKeyImpl extends PKCS8Key implements RSAPrivateKey {

    @java.io.Serial

    private static final long serialVersionUID = -33106691987952810L;

    private final BigInteger n;         // modulus

    private final BigInteger d;         // private exponent

    private transient final KeyType type;

    // optional parameters associated with this RSA key

    // specified in the encoding of its AlgorithmId.

    // must be null for "RSA" keys.

    private transient final AlgorithmParameterSpec keyParams;

    /**

     * Construct a key from its components. Used by the

     * RSAKeyFactory and the RSAKeyPairGenerator.

     */

    RSAPrivateKeyImpl(KeyType type, AlgorithmParameterSpec keyParams,

            BigInteger n, BigInteger d) throws InvalidKeyException {

        RSAKeyFactory.checkRSAProviderKeyLengths(n.bitLength(), null);

        this.n = n;

        this.d = d;

        try {

            // validate and generate the algid encoding

            algid = RSAUtil.createAlgorithmId(type, keyParams);

        } catch (ProviderException pe) {

            throw new InvalidKeyException(pe);

        }

        this.type = type;

        this.keyParams = keyParams;

        try {

            // generate the key encoding

            byte[] nbytes = n.toByteArray();

            byte[] dbytes = d.toByteArray();

            DerOutputStream out = new DerOutputStream(

                    nbytes.length + dbytes.length + 50);

                    // Enough for 7 zeroes (21) and 2 tag+length(4)

            out.putInteger(0); // version must be 0

            out.putInteger(nbytes);

            Arrays.fill(nbytes, (byte)0);

            out.putInteger(0);

            out.putInteger(dbytes);

            Arrays.fill(dbytes, (byte)0);

            out.putInteger(0);

            out.putInteger(0);

            out.putInteger(0);

            out.putInteger(0);

            out.putInteger(0);

            DerValue val = DerValue.wrap(DerValue.tag_Sequence, out);

            key = val.toByteArray();

            val.clear();

        } catch (IOException exc) {

            // should never occur

            throw new InvalidKeyException(exc);

        }

    }

    // see JCA doc

    @Override

    public String getAlgorithm() {

        return type.keyAlgo;

    }

    // see JCA doc

    @Override

    public BigInteger getModulus() {

        return n;

    }

    // see JCA doc

    @Override

    public BigInteger getPrivateExponent() {

        return d;

    }

    // see JCA doc

    @Override

    public AlgorithmParameterSpec getParams() {

        return keyParams;

    }

    // return a string representation of this key for debugging

    @Override

    public String toString() {

        return "Sun " + type.keyAlgo + " private key, " + n.bitLength()

               + " bits" + "\n  params: " + keyParams + "\n  modulus: " + n

               + "\n  private exponent: " + d;

    }

}