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 * Copyright (c) 1998, 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.x509;

import java.io.IOException;

import java.io.OutputStream;

import java.util.*;

import sun.security.util.*;

/**

 * Represents Netscape Certificate Type Extension.

 * The details are defined

 * <a href=http://www.netscape.com/eng/security/comm4-cert-exts.html>

 * here </a>.

 *

 * <p>This extension, if present, defines both the purpose

 * (e.g., encipherment, signature, certificate signing) and the application

 * (e.g., SSL, S/Mime or Object Signing of the key contained in the

 * certificate. This extension has been superseded by IETF PKIX extensions

 * but is provided here for compatibility reasons.

 *

 * @author Hemma Prafullchandra

 * @see Extension

 * @see CertAttrSet

 */

public class NetscapeCertTypeExtension extends Extension

implements CertAttrSet<String> {

    /**

     * Identifier for this attribute, to be used with the

     * get, set, delete methods of Certificate, x509 type.

     */

    public static final String IDENT = "x509.info.extensions.NetscapeCertType";

    /**

     * Attribute names.

     */

    public static final String NAME = "NetscapeCertType";

    public static final String SSL_CLIENT = "ssl_client";

    public static final String SSL_SERVER = "ssl_server";

    public static final String S_MIME = "s_mime";

    public static final String OBJECT_SIGNING = "object_signing";

    public static final String SSL_CA = "ssl_ca";

    public static final String S_MIME_CA = "s_mime_ca";

    public static final String OBJECT_SIGNING_CA = "object_signing_ca";

    private static final int[] CertType_data = { 2, 16, 840, 1, 113730, 1, 1 };

    /**

     * Object identifier for the Netscape-Cert-Type extension.

     */

    public static ObjectIdentifier NetscapeCertType_Id;

    static {

        try {

            NetscapeCertType_Id = new ObjectIdentifier(CertType_data);

        } catch (IOException ioe) {

            // should not happen

        }

    }

    private boolean[] bitString;

    private static class MapEntry {

        String mName;

        int mPosition;

        MapEntry(String name, int position) {

            mName = name;

            mPosition = position;

        }

    }

    private static MapEntry[] mMapData = {

        new MapEntry(SSL_CLIENT, 0),

        new MapEntry(SSL_SERVER, 1),

        new MapEntry(S_MIME, 2),

        new MapEntry(OBJECT_SIGNING, 3),

        // note that bit 4 is reserved

        new MapEntry(SSL_CA, 5),

        new MapEntry(S_MIME_CA, 6),

        new MapEntry(OBJECT_SIGNING_CA, 7),

    };

    private static final Vector<String> mAttributeNames = new Vector<String>();

    static {

        for (MapEntry entry : mMapData) {

            mAttributeNames.add(entry.mName);

        }

    }

    private static int getPosition(String name) throws IOException {

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

            if (name.equalsIgnoreCase(mMapData[i].mName))

                return mMapData[i].mPosition;

        }

        throw new IOException("Attribute name [" + name

                             + "] not recognized by CertAttrSet:NetscapeCertType.");

    }

    // Encode this extension value

    private void encodeThis() throws IOException {

        DerOutputStream os = new DerOutputStream();

        os.putTruncatedUnalignedBitString(new BitArray(this.bitString));

        this.extensionValue = os.toByteArray();

    }

    /**

     * Check if bit is set.

     *

     * @param position the position in the bit string to check.

     */

    private boolean isSet(int position) {

        return (position < bitString.length) &&

                bitString[position];

    }

    /**

     * Set the bit at the specified position.

     */

    private void set(int position, boolean val) {

        // enlarge bitString if necessary

        if (position >= bitString.length) {

            boolean[] tmp = new boolean[position+1];

            System.arraycopy(bitString, 0, tmp, 0, bitString.length);

            bitString = tmp;

        }

        bitString[position] = val;

    }

    /**

     * Create a NetscapeCertTypeExtension with the passed bit settings.

     * The criticality is set to true.

     *

     * @param bitString the bits to be set for the extension.

     */

    public NetscapeCertTypeExtension(byte[] bitString) throws IOException {

        this.bitString =

            new BitArray(bitString.length*8, bitString).toBooleanArray();

        this.extensionId = NetscapeCertType_Id;

        this.critical = true;

        encodeThis();

    }

    /**

     * Create a NetscapeCertTypeExtension with the passed bit settings.

     * The criticality is set to true.

     *

     * @param bitString the bits to be set for the extension.

     */

    public NetscapeCertTypeExtension(boolean[] bitString) throws IOException {

        this.bitString = bitString;

        this.extensionId = NetscapeCertType_Id;

        this.critical = true;

        encodeThis();

    }

    /**

     * Create the extension from the passed DER encoded value of the same.

     *

     * @param critical true if the extension is to be treated as critical.

     * @param value an array of DER encoded bytes of the actual value.

     * @exception ClassCastException if value is not an array of bytes

     * @exception IOException on error.

     */

    public NetscapeCertTypeExtension(Boolean critical, Object value)

    throws IOException {

        this.extensionId = NetscapeCertType_Id;

        this.critical = critical.booleanValue();

        this.extensionValue = (byte[]) value;

        DerValue val = new DerValue(this.extensionValue);

        this.bitString = val.getUnalignedBitString().toBooleanArray();

    }

    /**

     * Create a default key usage.

     */

    public NetscapeCertTypeExtension() {

        extensionId = NetscapeCertType_Id;

        critical = true;

        bitString = new boolean[0];

    }

    /**

     * Set the attribute value.

     */

    public void set(String name, Object obj) throws IOException {

        if (!(obj instanceof Boolean))

            throw new IOException("Attribute must be of type Boolean.");

        boolean val = ((Boolean)obj).booleanValue();

        set(getPosition(name), val);

        encodeThis();

    }

    /**

     * Get the attribute value.

     */

    public Boolean get(String name) throws IOException {

        return Boolean.valueOf(isSet(getPosition(name)));

    }

    /**

     * Delete the attribute value.

     */

    public void delete(String name) throws IOException {

        set(getPosition(name), false);

        encodeThis();

    }

    /**

     * Returns a printable representation of the NetscapeCertType.

     */

    public String toString() {

        StringBuilder sb = new StringBuilder();

        sb.append(super.toString());

        sb.append("NetscapeCertType [\n");

        if (isSet(0)) {

            sb.append("   SSL client\n");

        }

        if (isSet(1)) {

            sb.append("   SSL server\n");

        }

        if (isSet(2)) {

            sb.append("   S/MIME\n");

        }

        if (isSet(3)) {

            sb.append("   Object Signing\n");

        }

        if (isSet(5)) {

            sb.append("   SSL CA\n");

        }

        if (isSet(6)) {

            sb.append("   S/MIME CA\n");

        }

        if (isSet(7)) {

            sb.append("   Object Signing CA");

        }

        sb.append("]\n");

        return sb.toString();

    }

    /**

     * Write the extension to the DerOutputStream.

     *

     * @param out the DerOutputStream to write the extension to.

     * @exception IOException on encoding errors.

     */

    public void encode(OutputStream out) throws IOException {

        DerOutputStream  tmp = new DerOutputStream();

        if (this.extensionValue == null) {

            this.extensionId = NetscapeCertType_Id;

            this.critical = true;

            encodeThis();

        }

        super.encode(tmp);

        out.write(tmp.toByteArray());

    }

    /**

     * Return an enumeration of names of attributes existing within this

     * attribute.

     */

    public Enumeration<String> getElements() {

        return mAttributeNames.elements();

    }

    /**

     * Return the name of this attribute.

     */

    public String getName() {

        return (NAME);

    }

    /**

     * Get a boolean array representing the bits of this extension,

     * as it maps to the KeyUsage extension.

     * @return the bit values of this extension mapped to the bit values

     * of the KeyUsage extension as an array of booleans.

     */

    public boolean[] getKeyUsageMappedBits() {

        KeyUsageExtension keyUsage = new KeyUsageExtension();

        Boolean val = Boolean.TRUE;

        try {

            if (isSet(getPosition(SSL_CLIENT)) ||

                isSet(getPosition(S_MIME)) ||

                isSet(getPosition(OBJECT_SIGNING)))

                keyUsage.set(KeyUsageExtension.DIGITAL_SIGNATURE, val);

            if (isSet(getPosition(SSL_SERVER)))

                keyUsage.set(KeyUsageExtension.KEY_ENCIPHERMENT, val);

            if (isSet(getPosition(SSL_CA)) ||

                isSet(getPosition(S_MIME_CA)) ||

                isSet(getPosition(OBJECT_SIGNING_CA)))

                keyUsage.set(KeyUsageExtension.KEY_CERTSIGN, val);

        } catch (IOException e) { }

        return keyUsage.getBits();

    }

}