/*

 * Copyright (c) 2000, 2011, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 *

 *  (C) Copyright IBM Corp. 1999 All Rights Reserved.

 *  Copyright 1997 The Open Group Research Institute.  All rights reserved.

 */

package sun.security.krb5.internal;

import sun.security.krb5.Config;

import sun.security.krb5.PrincipalName;

import sun.security.krb5.KrbException;

import sun.security.krb5.Asn1Exception;

import sun.security.util.*;

import java.net.*;

import java.util.*;

import java.io.IOException;

import sun.security.krb5.internal.ccache.CCacheOutputStream;

/**

 * Implements the ASN.1 HostAddresses type.

 *

 * <pre>{@code

 * HostAddresses   -- NOTE: subtly different from rfc1510,

 *                 -- but has a value mapping and encodes the same

 *         ::= SEQUENCE OF HostAddress

 *

 * HostAddress     ::= SEQUENCE  {

 *         addr-type       [0] Int32,

 *         address         [1] OCTET STRING

 * }

 * }</pre>

 *

 * <p>

 * This definition reflects the Network Working Group RFC 4120

 * specification available at

 * <a href="http://www.ietf.org/rfc/rfc4120.txt">

 * http://www.ietf.org/rfc/rfc4120.txt</a>.

 */

public class HostAddresses implements Cloneable {

    private static boolean DEBUG = sun.security.krb5.internal.Krb5.DEBUG;

    private HostAddress[] addresses = null;

    private volatile int hashCode = 0;

    public HostAddresses(HostAddress[] new_addresses) throws IOException {

        if (new_addresses != null) {

           addresses = new HostAddress[new_addresses.length];

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

                if (new_addresses[i] == null) {

                   throw new IOException("Cannot create a HostAddress");

                } else {

                   addresses[i] = (HostAddress)new_addresses[i].clone();

                }

           }

        }

    }

    public HostAddresses() throws UnknownHostException {

        addresses = new HostAddress[1];

        addresses[0] = new HostAddress();

    }

    private HostAddresses(int dummy) {}

    public HostAddresses(PrincipalName serverPrincipal)

        throws UnknownHostException, KrbException {

        String[] components = serverPrincipal.getNameStrings();

        if (serverPrincipal.getNameType() != PrincipalName.KRB_NT_SRV_HST ||

            components.length < 2)

            throw new KrbException(Krb5.KRB_ERR_GENERIC, "Bad name");

        String host = components[1];

        InetAddress[] addr = InetAddress.getAllByName(host);

        HostAddress[] hAddrs = new HostAddress[addr.length];

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

            hAddrs[i] = new HostAddress(addr[i]);

        }

        addresses = hAddrs;

    }

    public Object clone() {

        HostAddresses new_hostAddresses = new HostAddresses(0);

        if (addresses != null) {

            new_hostAddresses.addresses = new HostAddress[addresses.length];

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

                new_hostAddresses.addresses[i] =

                        (HostAddress)addresses[i].clone();

            }

        }

        return new_hostAddresses;

    }

    public boolean inList(HostAddress addr) {

        if (addresses != null) {

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

                if (addresses[i].equals(addr))

                    return true;

        }

        return false;

    }

    public int hashCode() {

        if (hashCode == 0) {

            int result = 17;

            if (addresses != null) {

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

                    result = 37*result + addresses[i].hashCode();

                }

            }

            hashCode = result;

        }

        return hashCode;

    }

    public boolean equals(Object obj) {

        if (this == obj) {

            return true;

        }

        if (!(obj instanceof HostAddresses)) {

            return false;

        }

        HostAddresses addrs = (HostAddresses)obj;

        if ((addresses == null && addrs.addresses != null) ||

            (addresses != null && addrs.addresses == null))

            return false;

        if (addresses != null && addrs.addresses != null) {

            if (addresses.length != addrs.addresses.length)

                return false;

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

                if (!addresses[i].equals(addrs.addresses[i]))

                    return false;

        }

        return true;

    }

   /**

    * Constructs a new <code>HostAddresses</code> object.

    * @param encoding a single DER-encoded value.

    * @exception Asn1Exception if an error occurs while decoding an

    * ASN1 encoded data.

    * @exception IOException if an I/O error occurs while reading

    * encoded data.

    */

    public HostAddresses(DerValue encoding)

        throws  Asn1Exception, IOException {

        Vector<HostAddress> tempAddresses = new Vector<>();

        DerValue der = null;

        while (encoding.getData().available() > 0) {

            der = encoding.getData().getDerValue();

            tempAddresses.addElement(new HostAddress(der));

        }

        if (tempAddresses.size() > 0) {

            addresses = new HostAddress[tempAddresses.size()];

            tempAddresses.copyInto(addresses);

        }

    }

   /**

    * Encodes a <code>HostAddresses</code> object.

    * @return byte array of encoded <code>HostAddresses</code> object.

    * @exception Asn1Exception if an error occurs while decoding an

    * ASN1 encoded data.

    * @exception IOException if an I/O error occurs while reading

    * encoded data.

    */

    public byte[] asn1Encode() throws Asn1Exception, IOException {

        DerOutputStream bytes = new DerOutputStream();

        DerOutputStream temp = new DerOutputStream();

        if (addresses != null && addresses.length > 0) {

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

                bytes.write(addresses[i].asn1Encode());

        }

        temp.write(DerValue.tag_Sequence, bytes);

        return temp.toByteArray();

    }

    /**

     * Parse (unmarshal) a <code>HostAddresses</code> from a DER input stream.

     * This form

     * parsing might be used when expanding a value which is part of

     * a constructed sequence and uses explicitly tagged type.

     *

     * @exception Asn1Exception if an Asn1Exception occurs.

     * @param data the Der input stream value, which contains one or more

     * marshaled value.

     * @param explicitTag tag number.

     * @param optional indicates if this data field is optional.

     * @return an instance of <code>HostAddresses</code>.

     */

    public static HostAddresses parse(DerInputStream data,

                                      byte explicitTag, boolean optional)

        throws Asn1Exception, IOException {

        if ((optional) &&

            (((byte)data.peekByte() & (byte)0x1F) != explicitTag))

            return null;

        DerValue der = data.getDerValue();

        if (explicitTag != (der.getTag() & (byte)0x1F))  {

            throw new Asn1Exception(Krb5.ASN1_BAD_ID);

        } else {

            DerValue subDer = der.getData().getDerValue();

            return new HostAddresses(subDer);

        }

    }

    /**

         * Writes data field values in <code>HostAddresses</code> in FCC

         * format to a <code>CCacheOutputStream</code>.

         *

         * @param cos a <code>CCacheOutputStream</code> to be written to.

         * @exception IOException if an I/O exception occurs.

         * @see sun.security.krb5.internal.ccache.CCacheOutputStream

         */

    public void writeAddrs(CCacheOutputStream cos) throws IOException {

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

            cos.write32(0);

            return;

        }

        cos.write32(addresses.length);

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

            cos.write16(addresses[i].addrType);

            cos.write32(addresses[i].address.length);

            cos.write(addresses[i].address, 0,

                      addresses[i].address.length);

        }

    }

    public InetAddress[] getInetAddresses() {

        if (addresses == null || addresses.length == 0)

            return null;

        ArrayList<InetAddress> ipAddrs = new ArrayList<>(addresses.length);

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

            try {

                if ((addresses[i].addrType == Krb5.ADDRTYPE_INET) ||

                    (addresses[i].addrType == Krb5.ADDRTYPE_INET6)) {

                    ipAddrs.add(addresses[i].getInetAddress());

                }

            } catch (java.net.UnknownHostException e) {

                // Should not happen since IP address given

                return null;

            }

        }

        InetAddress[] retVal = new InetAddress[ipAddrs.size()];

        return ipAddrs.toArray(retVal);

    }

    /**

     * Returns all the IP addresses of the local host.

     */

    public static HostAddresses getLocalAddresses() throws IOException

    {

        Set<InetAddress> all = new LinkedHashSet<>();

        try {

            if (DEBUG) {

                System.out.println(">>> KrbKdcReq local addresses are:");

            }

            String extra = Config.getInstance().getAll(

                    "libdefaults", "extra_addresses");

            if (extra != null) {

                for (String s: extra.split("\\s+")) {

                    all.add(InetAddress.getByName(s));

                    if (DEBUG) {

                        System.out.println("   extra_addresses: "

                                + InetAddress.getByName(s));

                    }

                }

            }

            for (NetworkInterface ni:

                    Collections.list(NetworkInterface.getNetworkInterfaces())) {

                if (DEBUG) {

                    System.out.println("   NetworkInterface " + ni + ":");

                    System.out.println("      "

                            + Collections.list(ni.getInetAddresses()));

                }

                all.addAll(Collections.list(ni.getInetAddresses()));

            }

            return new HostAddresses(all.toArray(new InetAddress[all.size()]));

        } catch (Exception exc) {

            throw new IOException(exc.toString());

        }

    }

    /**

     * Creates a new HostAddresses instance from the supplied list

     * of InetAddresses.

     */

    public HostAddresses(InetAddress[] inetAddresses)

    {

        if (inetAddresses == null)

            {

                addresses = null;

                return;

            }

        addresses = new HostAddress[inetAddresses.length];

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

            addresses[i] = new HostAddress(inetAddresses[i]);

    }

    @Override

    public String toString() {

        return Arrays.toString(addresses);

    }

}