001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.commons.compress.archivers.zip;
020
021import java.util.zip.ZipException;
022
023/**
024 * X.509 Certificate ID and Signature for central directory (0x0016).
025 *
026 * <p>This field contains the information about which certificate in the PKCS#7
027 * store was used to sign the central directory structure. When the Central
028 * Directory Encryption feature is enabled for a ZIP file, this record will
029 * appear in the Archive Extra Data Record, otherwise it will appear in the
030 * first central directory record.</p>
031 *
032 * <p>Note: all fields stored in Intel low-byte/high-byte order.</p>
033 *
034 * <pre>
035 *         Value     Size     Description
036 *         -----     ----     -----------
037 * (CDID)  0x0016    2 bytes  Tag for this "extra" block type
038 *         TSize     2 bytes  Size of data that follows
039 *         RCount    4 bytes  Number of recipients. (inferred)
040 *         HashAlg   2 bytes  Hash algorithm identifier. (inferred)
041 *         TData     TSize    Data
042 * </pre>
043 *
044 * @NotThreadSafe
045 * @since 1.11
046 */
047public class X0016_CertificateIdForCentralDirectory extends PKWareExtraHeader {
048
049    public X0016_CertificateIdForCentralDirectory() {
050        super(new ZipShort(0x0016));
051    }
052
053    private int rcount;
054    private HashAlgorithm hashAlg;
055
056    /**
057     * Get record count.
058     * @return the record count
059     */
060    public int getRecordCount() {
061        return rcount;
062    }
063
064    /**
065     * Get hash algorithm.
066     * @return the hash algorithm
067     */
068    public HashAlgorithm getHashAlgorithm() {
069        return hashAlg;
070    }
071
072    @Override
073    public void parseFromCentralDirectoryData(final byte[] data, final int offset, final int length)
074        throws ZipException {
075        assertMinimalLength(4, length);
076        // TODO: double check we really do not want to call super here
077        this.rcount = ZipShort.getValue(data, offset);
078        this.hashAlg = HashAlgorithm.getAlgorithmByCode(ZipShort.getValue(data, offset + 2));
079    }
080}