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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.util;

import java.io.IOException;

import java.security.*;

import java.security.spec.*;

import sun.security.rsa.RSAUtil;

import jdk.internal.access.SharedSecrets;

/**

 * Utility class for Signature related operations. Currently used by various

 * internal PKI classes such as sun.security.x509.X509CertImpl,

 * sun.security.pkcs.SignerInfo, for setting signature parameters.

 *

 * @since   11

 */

public class SignatureUtil {

    private static String checkName(String algName) throws ProviderException {

        if (algName.indexOf(".") == -1) {

            return algName;

        }

        // convert oid to String

        try {

            return Signature.getInstance(algName).getAlgorithm();

        } catch (Exception e) {

            throw new ProviderException("Error mapping algorithm name", e);

        }

    }

    // Utility method of creating an AlgorithmParameters object with

    // the specified algorithm name and encoding

    private static AlgorithmParameters createAlgorithmParameters(String algName,

            byte[] paramBytes) throws ProviderException {

        try {

            algName = checkName(algName);

            AlgorithmParameters result =

                AlgorithmParameters.getInstance(algName);

            result.init(paramBytes);

            return result;

        } catch (NoSuchAlgorithmException | IOException e) {

            throw new ProviderException(e);

        }

    }

    // Utility method for converting the specified AlgorithmParameters object

    // into an AlgorithmParameterSpec object.

    public static AlgorithmParameterSpec getParamSpec(String sigName,

            AlgorithmParameters params)

            throws ProviderException {

        AlgorithmParameterSpec paramSpec = null;

        if (params != null) {

            // AlgorithmParameters.getAlgorithm() may returns oid if it's

            // created during DER decoding. Convert to use the standard name

            // before passing it to RSAUtil

            if (params.getAlgorithm().indexOf(".") != -1) {

                try {

                    params = createAlgorithmParameters(sigName,

                        params.getEncoded());

                } catch (IOException e) {

                    throw new ProviderException(e);

                }

            }

        }

        return paramSpec;

    }

    // Utility method for converting the specified parameter bytes into an

    // AlgorithmParameterSpec object.

    public static AlgorithmParameterSpec getParamSpec(String sigName,

            byte[] paramBytes)

            throws ProviderException {

        AlgorithmParameterSpec paramSpec = null;

        if (paramBytes != null) {

                throw new ProviderException

                     ("Unrecognized algorithm for signature parameters " +

                      sigName);

            }

        }

        return paramSpec;

    }

    // Utility method for initializing the specified Signature object

    // for verification with the specified key and params (may be null)

    public static void initVerifyWithParam(Signature s, PublicKey key,

            AlgorithmParameterSpec params)

            throws ProviderException, InvalidAlgorithmParameterException,

            InvalidKeyException {

        SharedSecrets.getJavaSecuritySignatureAccess().initVerify(s, key, params);

    }

    // Utility method for initializing the specified Signature object

    // for verification with the specified Certificate and params (may be null)

    public static void initVerifyWithParam(Signature s,

            java.security.cert.Certificate cert,

            AlgorithmParameterSpec params)

            throws ProviderException, InvalidAlgorithmParameterException,

            InvalidKeyException {

        SharedSecrets.getJavaSecuritySignatureAccess().initVerify(s, cert, params);

    }

    // Utility method for initializing the specified Signature object

    // for signing with the specified key and params (may be null)

    public static void initSignWithParam(Signature s, PrivateKey key,

            AlgorithmParameterSpec params, SecureRandom sr)

            throws ProviderException, InvalidAlgorithmParameterException,

            InvalidKeyException {

        SharedSecrets.getJavaSecuritySignatureAccess().initSign(s, key, params, sr);

    }

}