/*

 * Copyright (c) 2015, 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.pkcs11;

import java.io.IOException;

import java.math.BigInteger;

import java.security.*;

import java.security.interfaces.*;

import java.security.spec.*;

import sun.security.ec.ECPublicKeyImpl;

import sun.security.ec.ECPrivateKeyImpl;

import sun.security.x509.X509Key;

final class P11ECUtil {

    static ECPublicKey decodeX509ECPublicKey(byte[] encoded)

            throws InvalidKeySpecException {

        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(encoded);

        return (ECPublicKey)ECGeneratePublic(keySpec);

    }

    static byte[] x509EncodeECPublicKey(ECPoint w,

            ECParameterSpec params) throws InvalidKeySpecException {

        ECPublicKeySpec keySpec = new ECPublicKeySpec(w, params);

        X509Key key = (X509Key)ECGeneratePublic(keySpec);

        return key.getEncoded();

    }

    static ECPrivateKey decodePKCS8ECPrivateKey(byte[] encoded)

            throws InvalidKeySpecException {

        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(encoded);

        return (ECPrivateKey)ECGeneratePrivate(keySpec);

    }

    static ECPrivateKey generateECPrivateKey(BigInteger s,

            ECParameterSpec params) throws InvalidKeySpecException {

        ECPrivateKeySpec keySpec = new ECPrivateKeySpec(s, params);

        return (ECPrivateKey)ECGeneratePrivate(keySpec);

    }

    private static PublicKey ECGeneratePublic(KeySpec keySpec)

            throws InvalidKeySpecException {

        try {

            if (keySpec instanceof X509EncodedKeySpec) {

               X509EncodedKeySpec x509Spec = (X509EncodedKeySpec)keySpec;

                return new ECPublicKeyImpl(x509Spec.getEncoded());

            } else if (keySpec instanceof ECPublicKeySpec) {

                ECPublicKeySpec ecSpec = (ECPublicKeySpec)keySpec;

                return new ECPublicKeyImpl(

                    ecSpec.getW(),

                    ecSpec.getParams()

                );

            } else {

                throw new InvalidKeySpecException("Only ECPublicKeySpec "

                    + "and X509EncodedKeySpec supported for EC public keys");

            }

        } catch (InvalidKeySpecException e) {

            throw e;

        } catch (GeneralSecurityException e) {

            throw new InvalidKeySpecException(e);

        }

    }

    private static PrivateKey ECGeneratePrivate(KeySpec keySpec)

            throws InvalidKeySpecException {

        try {

            if (keySpec instanceof PKCS8EncodedKeySpec) {

                PKCS8EncodedKeySpec pkcsSpec = (PKCS8EncodedKeySpec)keySpec;

                return new ECPrivateKeyImpl(pkcsSpec.getEncoded());

            } else if (keySpec instanceof ECPrivateKeySpec) {

                ECPrivateKeySpec ecSpec = (ECPrivateKeySpec)keySpec;

                return new ECPrivateKeyImpl(ecSpec.getS(), ecSpec.getParams());

            } else {

                throw new InvalidKeySpecException("Only ECPrivateKeySpec "

                    + "and PKCS8EncodedKeySpec supported for EC private keys");

            }

        } catch (InvalidKeySpecException e) {

            throw e;

        } catch (GeneralSecurityException e) {

            throw new InvalidKeySpecException(e);

        }

    }

    private P11ECUtil() {}

}