| /* |
| * 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.shared.kerberos.components; |
| |
| |
| import java.nio.BufferOverflowException; |
| import java.nio.ByteBuffer; |
| import java.util.Arrays; |
| |
| import org.apache.directory.api.asn1.Asn1Object; |
| import org.apache.directory.api.asn1.EncoderException; |
| import org.apache.directory.api.asn1.ber.tlv.BerValue; |
| import org.apache.directory.api.asn1.ber.tlv.TLV; |
| import org.apache.directory.api.asn1.ber.tlv.UniversalTag; |
| import org.apache.directory.api.util.Strings; |
| import org.apache.directory.server.i18n.I18n; |
| import org.apache.directory.shared.kerberos.KerberosConstants; |
| import org.apache.directory.shared.kerberos.crypto.checksum.ChecksumType; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| |
| /** |
| * The Checksum structure is used to store a checksum associated to a type. |
| * |
| * The ASN.1 grammar is : |
| * <pre> |
| * Checksum ::= SEQUENCE { |
| * cksumtype [0] Int32, |
| * checksum [1] OCTET STRING |
| * } |
| * </pre> |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class Checksum implements Asn1Object |
| { |
| /** The logger */ |
| private static final Logger log = LoggerFactory.getLogger( Checksum.class ); |
| |
| /** Speedup for logs */ |
| private static final boolean IS_DEBUG = log.isDebugEnabled(); |
| |
| /** The checksum type used */ |
| private ChecksumType cksumtype; |
| |
| /** The byte array containing the checksum */ |
| private byte[] checksum; |
| |
| // Storage for computed lengths |
| private int checksumTypeLength; |
| private int checksumBytesLength; |
| private int checksumLength; |
| |
| |
| /** |
| * Creates a new instance of Checksum. |
| */ |
| public Checksum() |
| { |
| } |
| |
| |
| /** |
| * Creates a new instance of Checksum. |
| * |
| * @param cksumtype The checksum type used |
| * @param checksum The checksum value |
| */ |
| public Checksum( ChecksumType cksumtype, byte[] checksum ) |
| { |
| this.cksumtype = cksumtype; |
| this.checksum = checksum; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public int hashCode() |
| { |
| int hash = 37; |
| hash = hash * 17 + cksumtype.hashCode(); |
| hash = hash * 17 + Arrays.hashCode( checksum ); |
| |
| return hash; |
| } |
| |
| |
| /** |
| * @see Object#equals(Object) |
| */ |
| @Override |
| public boolean equals( Object o ) |
| { |
| if ( this == o ) |
| { |
| return true; |
| } |
| |
| if ( !( o instanceof Checksum ) ) |
| { |
| return false; |
| } |
| |
| Checksum that = ( Checksum ) o; |
| |
| return ( cksumtype == that.cksumtype ) && ( Arrays.equals( checksum, that.checksum ) ); |
| } |
| |
| |
| /** |
| * Returns the checksum value. |
| * |
| * @return The checksum value. |
| */ |
| public byte[] getChecksumValue() |
| { |
| return checksum; |
| } |
| |
| |
| /** |
| * Set the checksum Value. |
| * |
| * @param checksum The checksum value |
| */ |
| public void setChecksumValue( byte[] checksum ) |
| { |
| this.checksum = checksum; |
| } |
| |
| |
| /** |
| * Returns the {@link ChecksumType}. |
| * |
| * @return The {@link ChecksumType}. |
| */ |
| public ChecksumType getChecksumType() |
| { |
| return cksumtype; |
| } |
| |
| |
| /** |
| * Set the {@link ChecksumType}. |
| * |
| * @param cksumType The checksum algorithm used |
| */ |
| public void setChecksumType( ChecksumType cksumType ) |
| { |
| this.cksumtype = cksumType; |
| } |
| |
| |
| /** |
| * Compute the checksum length |
| * <pre> |
| * Checksum : |
| * |
| * 0x30 L1 checksum sequence |
| * | |
| * +--> 0xA0 L2 cksumtype tag |
| * | | |
| * | +--> 0x02 L2-1 cksumtype (int) |
| * | |
| * +--> 0xA1 L3 checksum tag |
| * | |
| * +--> 0x04 L3-1 checksum (OCTET STRING) |
| * |
| * where L1 = L2 + lenght(0xA0) + length(L2) + |
| * L3 + lenght(0xA1) + length(L3) |
| * and |
| * L2 = L2-1 + length(0x02) + length( L2-1) |
| * L3 = L3-1 + length(0x04) + length( L3-1) |
| * </pre> |
| */ |
| public int computeLength() |
| { |
| // Compute the checksulType. The Length will always be contained in 1 byte |
| checksumTypeLength = 1 + 1 + BerValue.getNbBytes( cksumtype.getValue() ); |
| checksumLength = 1 + TLV.getNbBytes( checksumTypeLength ) + checksumTypeLength; |
| |
| // Compute the checksum Value |
| if ( checksum == null ) |
| { |
| checksumBytesLength = 1 + 1; |
| } |
| else |
| { |
| checksumBytesLength = 1 + TLV.getNbBytes( checksum.length ) + checksum.length; |
| } |
| |
| checksumLength += 1 + TLV.getNbBytes( checksumBytesLength ) + checksumBytesLength; |
| |
| // Compute the whole sequence length |
| int checksumSeqLength = 1 + TLV.getNbBytes( checksumLength ) + checksumLength; |
| |
| return checksumSeqLength; |
| |
| } |
| |
| |
| /** |
| * Encode the Checksum message to a PDU. |
| * |
| * <pre> |
| * Checksum : |
| * |
| * 0x30 LL |
| * 0xA0 LL |
| * 0x02 0x01 cksumtype |
| * 0xA1 LL |
| * 0x04 LL Checksum |
| * </pre> |
| * @param buffer The buffer where to put the PDU. It should have been allocated |
| * before, with the right size. |
| * @return The constructed PDU. |
| */ |
| public ByteBuffer encode( ByteBuffer buffer ) throws EncoderException |
| { |
| if ( buffer == null ) |
| { |
| throw new EncoderException( I18n.err( I18n.ERR_148 ) ); |
| } |
| |
| try |
| { |
| // The Checksum SEQ Tag |
| buffer.put( UniversalTag.SEQUENCE.getValue() ); |
| buffer.put( TLV.getBytes( checksumLength ) ); |
| |
| // The cksumtype, first the tag, then the value |
| buffer.put( ( byte ) KerberosConstants.CHECKSUM_TYPE_TAG ); |
| buffer.put( TLV.getBytes( checksumTypeLength ) ); |
| BerValue.encode( buffer, cksumtype.getValue() ); |
| |
| // The checksum, first the tag, then the value |
| buffer.put( ( byte ) KerberosConstants.CHECKSUM_CHECKSUM_TAG ); |
| buffer.put( TLV.getBytes( checksumBytesLength ) ); |
| BerValue.encode( buffer, checksum ); |
| } |
| catch ( BufferOverflowException boe ) |
| { |
| log.error( I18n.err( I18n.ERR_140, 1 + TLV.getNbBytes( checksumLength ) + checksumLength, |
| buffer.capacity() ) ); |
| throw new EncoderException( I18n.err( I18n.ERR_138 ) ); |
| } |
| |
| if ( IS_DEBUG ) |
| { |
| log.debug( "Checksum encoding : {}", Strings.dumpBytes( buffer.array() ) ); |
| log.debug( "Checksum initial value : {}", toString() ); |
| } |
| |
| return buffer; |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString() |
| { |
| return toString( "" ); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString( String tabs ) |
| { |
| StringBuilder sb = new StringBuilder(); |
| |
| sb.append( tabs ).append( "Checksum : {\n" ); |
| sb.append( tabs ).append( " cksumtype: " ).append( cksumtype ).append( '\n' ); |
| |
| if ( checksum != null ) |
| { |
| sb.append( tabs + " checksum:" ).append( Strings.dumpBytes( checksum ) ).append( '\n' ); |
| } |
| |
| sb.append( tabs + "}\n" ); |
| |
| return sb.toString(); |
| } |
| } |