/*
* 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.crypto.encryption.EncryptionType;
import org.apache.directory.server.kerberos.shared.messages.value.EncryptionTypeInfo2Entry;
import org.apache.directory.shared.asn1.der.ASN1InputStream;
import org.apache.directory.shared.asn1.der.DEREncodable;
import org.apache.directory.shared.asn1.der.DERGeneralString;
import org.apache.directory.shared.asn1.der.DERInteger;
import org.apache.directory.shared.asn1.der.DEROctetString;
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: 540371 $, $Date: 2007-05-21 17:00:43 -0700 (Mon, 21 May 2007) $
*/
public class EncryptionTypeInfo2Decoder
{
/**
* Decodes a byte array into an array of {@link EncryptionTypeInfo2Entry}.
*
* @param encodedEntries
* @return The array of {@link EncryptionTypeInfo2Entry}.
* @throws IOException
*/
public EncryptionTypeInfo2Entry[] decode( byte[] encodedEntries ) throws IOException
{
ASN1InputStream ais = new ASN1InputStream( encodedEntries );
DERSequence sequence = ( DERSequence ) ais.readObject();
return decodeSequence( sequence );
}
/**
* ETYPE-INFO2 ::= SEQUENCE SIZE (1..MAX) OF ETYPE-INFO2-ENTRY
*/
protected static EncryptionTypeInfo2Entry[] decodeSequence( DERSequence sequence )
{
EncryptionTypeInfo2Entry[] entrySequence = new EncryptionTypeInfo2Entry[sequence.size()];
int ii = 0;
for ( Enumeration<DEREncodable> e = sequence.getObjects(); e.hasMoreElements(); )
{
DERSequence object = (DERSequence)e.nextElement();
entrySequence[ii] = decode( object );
ii++;
}
return entrySequence;
}
/**
* ETYPE-INFO2-ENTRY ::= SEQUENCE {
* etype [0] Int32,
* salt [1] KerberosString OPTIONAL,
* s2kparams [2] OCTET STRING OPTIONAL
* }
*/
protected static EncryptionTypeInfo2Entry decode( DERSequence sequence )
{
EncryptionType encryptionType = EncryptionType.NULL;
String salt = new String();
byte[] s2kparams = new byte[0];
for ( Enumeration<DEREncodable> 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;
encryptionType = EncryptionType.getTypeByOrdinal( tag0.intValue() );
break;
case 1:
DERGeneralString tag1 = ( DERGeneralString ) derObject;
salt = tag1.getString();
break;
case 2:
DEROctetString tag2 = ( DEROctetString ) derObject;
s2kparams = tag2.getOctets();
break;
}
}
return new EncryptionTypeInfo2Entry( encryptionType, salt, s2kparams );
}
}