/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
package org.apache.directory.server.kerberos.shared.io.decoder;
import java.io.IOException;
import java.util.Enumeration;
import org.apache.directory.server.kerberos.shared.messages.Encodable;
import org.apache.directory.server.kerberos.shared.messages.components.Authenticator;
import org.apache.directory.server.kerberos.shared.messages.components.AuthenticatorModifier;
import org.apache.directory.shared.asn1.der.ASN1InputStream;
import org.apache.directory.shared.asn1.der.DERApplicationSpecific;
import org.apache.directory.shared.asn1.der.DEREncodable;
import org.apache.directory.shared.asn1.der.DERGeneralString;
import org.apache.directory.shared.asn1.der.DERGeneralizedTime;
import org.apache.directory.shared.asn1.der.DERInteger;
import org.apache.directory.shared.asn1.der.DERSequence;
import org.apache.directory.shared.asn1.der.DERTaggedObject;
/**
* @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
* @version $Rev: 502338 $, $Date: 2007-02-01 20:59:43 +0100 (Jeu, 01 fév 2007) $
*/
public class AuthenticatorDecoder implements Decoder, DecoderFactory
{
public Decoder getDecoder()
{
return new AuthenticatorDecoder();
}
public Encodable decode( byte[] encodedAuthenticator ) throws IOException
{
ASN1InputStream ais = new ASN1InputStream( encodedAuthenticator );
DERApplicationSpecific app = ( DERApplicationSpecific ) ais.readObject();
DERSequence sequence = ( DERSequence ) app.getObject();
return decode( sequence );
}
/**
* -- Unencrypted authenticator
* Authenticator ::= [APPLICATION 2] SEQUENCE
* {
* authenticator-vno[0] INTEGER,
* crealm[1] Realm,
* cname[2] PrincipalName,
* cksum[3] Checksum OPTIONAL,
* cusec[4] INTEGER,
* ctime[5] KerberosTime,
* subkey[6] EncryptionKey OPTIONAL,
* seq-number[7] INTEGER OPTIONAL,
*
* authorization-data[8] AuthorizationData OPTIONAL
* }
*/
protected static Authenticator decode( DERSequence sequence )
{
AuthenticatorModifier modifier = new AuthenticatorModifier();
for ( Enumeration e = sequence.getObjects(); e.hasMoreElements(); )
{
DERTaggedObject object = ( DERTaggedObject ) e.nextElement();
int tag = object.getTagNo();
DEREncodable derObject = object.getObject();
switch ( tag )
{
case 0:
DERInteger tag0 = ( DERInteger ) derObject;
modifier.setVersionNumber( tag0.intValue() );
break;
case 1:
DERGeneralString tag1 = ( DERGeneralString ) derObject;
modifier.setClientRealm( tag1.getString() );
break;
case 2:
DERSequence tag2 = ( DERSequence ) derObject;
modifier.setClientName( PrincipalNameDecoder.decode( tag2 ) );
break;
case 3:
DERSequence tag3 = ( DERSequence ) derObject;
modifier.setChecksum( ChecksumDecoder.decode( tag3 ) );
break;
case 4:
DERInteger tag4 = ( DERInteger ) derObject;
modifier.setClientMicroSecond( tag4.intValue() );
break;
case 5:
DERGeneralizedTime tag5 = ( DERGeneralizedTime ) derObject;
modifier.setClientTime( KerberosTimeDecoder.decode( tag5 ) );
break;
case 6:
DERSequence tag6 = ( DERSequence ) derObject;
modifier.setSubSessionKey( EncryptionKeyDecoder.decode( tag6 ) );
break;
case 7:
DERInteger tag7 = ( DERInteger ) derObject;
modifier.setSequenceNumber( tag7.intValue() );
break;
case 8:
DERSequence tag8 = ( DERSequence ) derObject;
modifier.setAuthorizationData( AuthorizationDataDecoder.decodeSequence( tag8 ) );
break;
}
}
return modifier.getAuthenticator();
}
}