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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 com.sun.crypto.provider;

import java.io.IOException;

import java.security.AlgorithmParametersSpi;

import java.security.spec.AlgorithmParameterSpec;

import java.security.spec.InvalidParameterSpecException;

import javax.crypto.spec.RC2ParameterSpec;

import sun.misc.HexDumpEncoder;

import sun.security.util.*;

/**

 * This class implements the parameter set used with RC2

 * encryption, which is defined in RFC2268 as follows:

 *

 * <pre>

 * RC2-CBCParameter ::= CHOICE {

 *   iv IV,

 *   params SEQUENCE {

 *     version RC2Version,

 *     iv IV

 *   }

 * }

 *

 * where

 *

 * IV ::= OCTET STRING -- 8 octets

 * RC2Version ::= INTEGER -- 1-1024

 * </pre>

 *

 * @author Sean Mullan

 * @since 1.5

 */

public final class RC2Parameters extends AlgorithmParametersSpi {

    // TABLE[EKB] from section 6 of RFC 2268, used to convert effective key

    // size to/from encoded version number

        0xbd, 0x56, 0xea, 0xf2, 0xa2, 0xf1, 0xac, 0x2a,

        0xb0, 0x93, 0xd1, 0x9c, 0x1b, 0x33, 0xfd, 0xd0,

        0x30, 0x04, 0xb6, 0xdc, 0x7d, 0xdf, 0x32, 0x4b,

        0xf7, 0xcb, 0x45, 0x9b, 0x31, 0xbb, 0x21, 0x5a,

        0x41, 0x9f, 0xe1, 0xd9, 0x4a, 0x4d, 0x9e, 0xda,

        0xa0, 0x68, 0x2c, 0xc3, 0x27, 0x5f, 0x80, 0x36,

        0x3e, 0xee, 0xfb, 0x95, 0x1a, 0xfe, 0xce, 0xa8,

        0x34, 0xa9, 0x13, 0xf0, 0xa6, 0x3f, 0xd8, 0x0c,

        0x78, 0x24, 0xaf, 0x23, 0x52, 0xc1, 0x67, 0x17,

        0xf5, 0x66, 0x90, 0xe7, 0xe8, 0x07, 0xb8, 0x60,

        0x48, 0xe6, 0x1e, 0x53, 0xf3, 0x92, 0xa4, 0x72,

        0x8c, 0x08, 0x15, 0x6e, 0x86, 0x00, 0x84, 0xfa,

        0xf4, 0x7f, 0x8a, 0x42, 0x19, 0xf6, 0xdb, 0xcd,

        0x14, 0x8d, 0x50, 0x12, 0xba, 0x3c, 0x06, 0x4e,

        0xec, 0xb3, 0x35, 0x11, 0xa1, 0x88, 0x8e, 0x2b,

        0x94, 0x99, 0xb7, 0x71, 0x74, 0xd3, 0xe4, 0xbf,

        0x3a, 0xde, 0x96, 0x0e, 0xbc, 0x0a, 0xed, 0x77,

        0xfc, 0x37, 0x6b, 0x03, 0x79, 0x89, 0x62, 0xc6,

        0xd7, 0xc0, 0xd2, 0x7c, 0x6a, 0x8b, 0x22, 0xa3,

        0x5b, 0x05, 0x5d, 0x02, 0x75, 0xd5, 0x61, 0xe3,

        0x18, 0x8f, 0x55, 0x51, 0xad, 0x1f, 0x0b, 0x5e,

        0x85, 0xe5, 0xc2, 0x57, 0x63, 0xca, 0x3d, 0x6c,

        0xb4, 0xc5, 0xcc, 0x70, 0xb2, 0x91, 0x59, 0x0d,

        0x47, 0x20, 0xc8, 0x4f, 0x58, 0xe0, 0x01, 0xe2,

        0x16, 0x38, 0xc4, 0x6f, 0x3b, 0x0f, 0x65, 0x46,

        0xbe, 0x7e, 0x2d, 0x7b, 0x82, 0xf9, 0x40, 0xb5,

        0x1d, 0x73, 0xf8, 0xeb, 0x26, 0xc7, 0x87, 0x97,

        0x25, 0x54, 0xb1, 0x28, 0xaa, 0x98, 0x9d, 0xa5,

        0x64, 0x6d, 0x7a, 0xd4, 0x10, 0x81, 0x44, 0xef,

        0x49, 0xd6, 0xae, 0x2e, 0xdd, 0x76, 0x5c, 0x2f,

        0xa7, 0x1c, 0xc9, 0x09, 0x69, 0x9a, 0x83, 0xcf,

        0x29, 0x39, 0xb9, 0xe9, 0x4c, 0xff, 0x43, 0xab

    };

    // the iv

    private byte[] iv;

    // the version number

    private int version = 0;

    // the effective key size

    private int effectiveKeySize = 0;

    public RC2Parameters() {}

    protected void engineInit(AlgorithmParameterSpec paramSpec)

        throws InvalidParameterSpecException {

        if (!(paramSpec instanceof RC2ParameterSpec)) {

            throw new InvalidParameterSpecException

                ("Inappropriate parameter specification");

        }

        RC2ParameterSpec rps = (RC2ParameterSpec) paramSpec;

        // check effective key size (a value of 0 means it is unspecified)

        effectiveKeySize = rps.getEffectiveKeyBits();

        if (effectiveKeySize != 0) {

            if (effectiveKeySize < 1 || effectiveKeySize > 1024) {

                throw new InvalidParameterSpecException("RC2 effective key " +

                    "size must be between 1 and 1024 bits");

            }

            if (effectiveKeySize < 256) {

                version = EKB_TABLE[effectiveKeySize];

            } else {

                version = effectiveKeySize;

            }

        }

        this.iv = rps.getIV();

    }

    protected void engineInit(byte[] encoded) throws IOException {

        DerValue val = new DerValue(encoded);

        // check if IV or params

        if (val.tag == DerValue.tag_Sequence) {

            val.data.reset();

            version = val.data.getInteger();

            if (version < 0 || version > 1024) {

                throw new IOException("RC2 parameter parsing error: " +

                    "version number out of legal range (0-1024): " + version);

            }

            if (version > 255) {

                effectiveKeySize = version;

            } else {

                // search table for index containing version

                for (int i = 0; i < EKB_TABLE.length; i++) {

                    if (version == EKB_TABLE[i]) {

                        effectiveKeySize = i;

                        break;

                    }

                }

            }

            iv = val.data.getOctetString();

        } else {

            val.data.reset();

            iv = val.getOctetString();

            version = 0;

            effectiveKeySize = 0;

        }

        if (iv.length != 8) {

            throw new IOException("RC2 parameter parsing error: iv length " +

                "must be 8 bits, actual: " + iv.length);

        }

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

            throw new IOException("RC2 parameter parsing error: extra data");

        }

    }

    protected void engineInit(byte[] encoded, String decodingMethod)

        throws IOException {

        engineInit(encoded);

    }

    protected <T extends AlgorithmParameterSpec>

            T engineGetParameterSpec(Class<T> paramSpec)

        throws InvalidParameterSpecException {

        if (RC2ParameterSpec.class.isAssignableFrom(paramSpec)) {

            return paramSpec.cast((iv == null ?

                                   new RC2ParameterSpec(effectiveKeySize) :

                                   new RC2ParameterSpec(effectiveKeySize, iv)));

        } else {

            throw new InvalidParameterSpecException

                ("Inappropriate parameter specification");

        }

    }

    protected byte[] engineGetEncoded() throws IOException {

        DerOutputStream out = new DerOutputStream();

        DerOutputStream bytes = new DerOutputStream();

        if (this.effectiveKeySize != 0) {

            bytes.putInteger(version);

            bytes.putOctetString(iv);

            out.write(DerValue.tag_Sequence, bytes);

        } else {

            out.putOctetString(iv);

        }

        return out.toByteArray();

    }

    protected byte[] engineGetEncoded(String encodingMethod)

        throws IOException {

        return engineGetEncoded();

    }

    /*

     * Returns a formatted string describing the parameters.

     */

    protected String engineToString() {

        String LINE_SEP = System.getProperty("line.separator");

        HexDumpEncoder encoder = new HexDumpEncoder();

        StringBuilder sb

            = new StringBuilder(LINE_SEP + "    iv:" + LINE_SEP + "["

                + encoder.encodeBuffer(iv) + "]");

        if (version != 0) {

            sb.append(LINE_SEP + "version:" + LINE_SEP

                + version + LINE_SEP);

        }

        return sb.toString();

    }

}