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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.

 *

 * 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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 *

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package sun.security.rsa;

import java.io.IOException;

import java.math.BigInteger;

import java.security.*;

import java.security.spec.*;

import java.security.interfaces.*;

import sun.security.util.*;

import sun.security.x509.AlgorithmId;

import sun.security.pkcs.PKCS8Key;

import static sun.security.rsa.RSAUtil.KeyType;

/**

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

 * For non-CRT private keys, see RSAPrivateKeyImpl. We need separate classes

 * to ensure correct behavior in instanceof checks, etc.

 *

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

 *

 * @see RSAPrivateKeyImpl

 * @see RSAKeyFactory

 *

 * @since   1.5

 * @author  Andreas Sterbenz

 */

public final class RSAPrivateCrtKeyImpl

        extends PKCS8Key implements RSAPrivateCrtKey {

    @java.io.Serial

    private static final long serialVersionUID = -1326088454257084918L;

    private BigInteger n;       // modulus

    private BigInteger e;       // public exponent

    private BigInteger d;       // private exponent

    private BigInteger p;       // prime p

    private BigInteger q;       // prime q

    private BigInteger pe;      // prime exponent p

    private BigInteger qe;      // prime exponent q

    private BigInteger coeff;   // CRT coeffcient

    // Optional parameters associated with this RSA key

    // specified in the encoding of its AlgorithmId.

    // Must be null for "RSA" keys.

    @SuppressWarnings("serial") // Not statically typed as Serializable

    private AlgorithmParameterSpec keyParams;

    /**

     * Generate a new key from its encoding. Returns a CRT key if possible

     * and a non-CRT key otherwise. Used by RSAKeyFactory.

     */

    public static RSAPrivateKey newKey(byte[] encoded)

            throws InvalidKeyException {

        RSAPrivateCrtKeyImpl key = new RSAPrivateCrtKeyImpl(encoded);

        // check all CRT-specific components are available, if any one

        // missing, return a non-CRT key instead

        if ((key.getPublicExponent().signum() == 0) ||

            (key.getPrimeExponentP().signum() == 0) ||

            (key.getPrimeExponentQ().signum() == 0) ||

            (key.getPrimeP().signum() == 0) ||

            (key.getPrimeQ().signum() == 0) ||

            (key.getCrtCoefficient().signum() == 0)) {

            return new RSAPrivateKeyImpl(

                key.algid,

                key.getModulus(),

                key.getPrivateExponent()

            );

        } else {

            return key;

        }

    }

    /**

     * Generate a new key from the specified type and components.

     * Returns a CRT key if possible and a non-CRT key otherwise.

     * Used by SunPKCS11 provider.

     */

    public static RSAPrivateKey newKey(KeyType type,

            AlgorithmParameterSpec params,

            BigInteger n, BigInteger e, BigInteger d,

            BigInteger p, BigInteger q, BigInteger pe, BigInteger qe,

            BigInteger coeff) throws InvalidKeyException {

        RSAPrivateKey key;

        AlgorithmId rsaId = RSAUtil.createAlgorithmId(type, params);

        if ((e.signum() == 0) || (p.signum() == 0) ||

            (q.signum() == 0) || (pe.signum() == 0) ||

            (qe.signum() == 0) || (coeff.signum() == 0)) {

            // if any component is missing, return a non-CRT key

            return new RSAPrivateKeyImpl(rsaId, n, d);

        } else {

            return new RSAPrivateCrtKeyImpl(rsaId, n, e, d,

                p, q, pe, qe, coeff);

        }

    }

    /**

     * Construct a key from its encoding. Called from newKey above.

     */

    RSAPrivateCrtKeyImpl(byte[] encoded) throws InvalidKeyException {

        if (encoded == null || encoded.length == 0) {

            throw new InvalidKeyException("Missing key encoding");

        }

        decode(encoded);

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

        try {

            // this will check the validity of params

            this.keyParams = RSAUtil.getParamSpec(algid);

        } catch (ProviderException e) {

            throw new InvalidKeyException(e);

        }

    }

    /**

     * Construct a RSA key from its components. Used by the

     * RSAKeyFactory and the RSAKeyPairGenerator.

     */

    RSAPrivateCrtKeyImpl(AlgorithmId rsaId,

            BigInteger n, BigInteger e, BigInteger d,

            BigInteger p, BigInteger q, BigInteger pe, BigInteger qe,

            BigInteger coeff) throws InvalidKeyException {

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

        this.n = n;

        this.e = e;

        this.d = d;

        this.p = p;

        this.q = q;

        this.pe = pe;

        this.qe = qe;

        this.coeff = coeff;

        this.keyParams = RSAUtil.getParamSpec(rsaId);

        // generate the encoding

        algid = rsaId;

        try {

            DerOutputStream out = new DerOutputStream();

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

            out.putInteger(n);

            out.putInteger(e);

            out.putInteger(d);

            out.putInteger(p);

            out.putInteger(q);

            out.putInteger(pe);

            out.putInteger(qe);

            out.putInteger(coeff);

            DerValue val =

                new DerValue(DerValue.tag_Sequence, out.toByteArray());

            key = val.toByteArray();

        } catch (IOException exc) {

            // should never occur

            throw new InvalidKeyException(exc);

        }

    }

    // see JCA doc

    @Override

    public String getAlgorithm() {

        return algid.getName();

    }

    // see JCA doc

    @Override

    public BigInteger getModulus() {

        return n;

    }

    // see JCA doc

    @Override

    public BigInteger getPublicExponent() {

        return e;

    }

    // see JCA doc

    @Override

    public BigInteger getPrivateExponent() {

        return d;

    }

    // see JCA doc

    @Override

    public BigInteger getPrimeP() {

        return p;

    }

    // see JCA doc

    @Override

    public BigInteger getPrimeQ() {

        return q;

    }

    // see JCA doc

    @Override

    public BigInteger getPrimeExponentP() {

        return pe;

    }

    // see JCA doc

    @Override

    public BigInteger getPrimeExponentQ() {

        return qe;

    }

    // see JCA doc

    @Override

    public BigInteger getCrtCoefficient() {

        return coeff;

    }

    // see JCA doc

    @Override

    public AlgorithmParameterSpec getParams() {

        return keyParams;

    }

    // return a string representation of this key for debugging

    @Override

    public String toString() {

        return "SunRsaSign " + getAlgorithm() + " private CRT key, " + n.bitLength()

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

               + "\n  private exponent: " + d;

    }

    /**

     * Parse the key. Called by PKCS8Key.

     */

    protected void parseKeyBits() throws InvalidKeyException {

        try {

            DerInputStream in = new DerInputStream(key);

            DerValue derValue = in.getDerValue();

            if (derValue.tag != DerValue.tag_Sequence) {

                throw new IOException("Not a SEQUENCE");

            }

            DerInputStream data = derValue.data;

            int version = data.getInteger();

            if (version != 0) {

                throw new IOException("Version must be 0");

            }

            /*

             * Some implementations do not correctly encode ASN.1 INTEGER values

             * in 2's complement format, resulting in a negative integer when

             * decoded. Correct the error by converting it to a positive integer.

             *

             * See CR 6255949

             */

            n = data.getPositiveBigInteger();

            e = data.getPositiveBigInteger();

            d = data.getPositiveBigInteger();

            p = data.getPositiveBigInteger();

            q = data.getPositiveBigInteger();

            pe = data.getPositiveBigInteger();

            qe = data.getPositiveBigInteger();

            coeff = data.getPositiveBigInteger();

            if (derValue.data.available() != 0) {

                throw new IOException("Extra data available");

            }

        } catch (IOException e) {

            throw new InvalidKeyException("Invalid RSA private key", e);

        }

    }

}