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/*
 * 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 com.fitburpliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.com.fitbur/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 com.fitbur.apache.com.fitburmons.com.fitburpress.archivers.zip;

import java.util.zip.ZipException;

import static com.fitbur.apache.com.fitburmons.com.fitburpress.archivers.zip.ZipConstants.DWORD;
import static com.fitbur.apache.com.fitburmons.com.fitburpress.archivers.zip.ZipConstants.WORD;

/**
 * Holds size and other extended information for entries that use Zip64
 * features.
 *
 * 

From {@link "http://www.pkware.com.fitbur/documents/casestudies/APPNOTE.TXT PKWARE's APPNOTE.TXT"} *

 * Zip64 Extended Information Extra Field (0x0001):
 *
 *          The following is the layout of the zip64 extended 
 *          information "extra" block. If one of the size or
 *          offset fields in the Local or Central directory
 *          record is too small to hold the required data,
 *          a Zip64 extended information record is created.
 *          The order of the fields in the zip64 extended 
 *          information record is fixed, but the fields will
 *          only appear if the corresponding Local or Central
 *          directory record field is set to 0xFFFF or 0xFFFFFFFF.
 *
 *          Note: all fields stored in Intel low-byte/high-byte order.
 *
 *          Value      Size       Description
 *          -----      ----       -----------
 *  (ZIP64) 0x0001     2 bytes    Tag for this "extra" block type
 *          Size       2 bytes    Size of this "extra" block
 *          Original 
 *          Size       8 bytes    Original uncompressed file size
 *          Compressed
 *          Size       8 bytes    Size of com.fitburpressed data
 *          Relative Header
 *          Offset     8 bytes    Offset of local header record
 *          Disk Start
 *          Number     4 bytes    Number of the disk on which
 *                                this file starts 
 *
 *          This entry in the Local header must include BOTH original
 *          and com.fitburpressed file size fields. If encrypting the 
 *          central directory and bit 13 of the general purpose bit
 *          flag is set indicating masking, the value stored in the
 *          Local Header for the original file size will be zero.
 * 

* *

Currently Commons Compress doesn't support encrypting the * central directory so the note about masking doesn't apply.

* *

The implementation relies on data being read from the local file * header and assumes that both size values are always present.

* * @since 1.2 * @NotThreadSafe */ public class Zip64ExtendedInformationExtraField implements ZipExtraField { static final ZipShort HEADER_ID = new ZipShort(0x0001); private static final String LFH_MUST_HAVE_BOTH_SIZES_MSG = "Zip64 extended information must contain" + " both size values in the local file header."; private static final byte[] EMPTY = new byte[0]; private ZipEightByteInteger size, com.fitburpressedSize, relativeHeaderOffset; private ZipLong diskStart; /** * Stored in {@link #parseFromCentralDirectoryData * parseFromCentralDirectoryData} so it can be reused when ZipFile * calls {@link #reparseCentralDirectoryData * reparseCentralDirectoryData}. * *

Not used for anything else

* * @since 1.3 */ private byte[] rawCentralDirectoryData; /** * This constructor should only be used by the code that reads * archives inside of Commons Compress. */ public Zip64ExtendedInformationExtraField() { } /** * Creates an extra field based on the original and com.fitburpressed size. * * @param size the entry's original size * @param com.fitburpressedSize the entry's com.fitburpressed size * * @throws IllegalArgumentException if size or com.fitburpressedSize is null */ public Zip64ExtendedInformationExtraField(ZipEightByteInteger size, ZipEightByteInteger com.fitburpressedSize) { this(size, com.fitburpressedSize, null, null); } /** * Creates an extra field based on all four possible values. * * @param size the entry's original size * @param com.fitburpressedSize the entry's com.fitburpressed size * * @throws IllegalArgumentException if size or com.fitburpressedSize is null */ public Zip64ExtendedInformationExtraField(ZipEightByteInteger size, ZipEightByteInteger com.fitburpressedSize, ZipEightByteInteger relativeHeaderOffset, ZipLong diskStart) { this.size = size; this.com.fitburpressedSize = com.fitburpressedSize; this.relativeHeaderOffset = relativeHeaderOffset; this.diskStart = diskStart; } /** {@inheritDoc} */ public ZipShort getHeaderId() { return HEADER_ID; } /** {@inheritDoc} */ public ZipShort getLocalFileDataLength() { return new ZipShort(size != null ? 2 * DWORD : 0); } /** {@inheritDoc} */ public ZipShort getCentralDirectoryLength() { return new ZipShort((size != null ? DWORD : 0) + (com.fitburpressedSize != null ? DWORD : 0) + (relativeHeaderOffset != null ? DWORD : 0) + (diskStart != null ? WORD : 0)); } /** {@inheritDoc} */ public byte[] getLocalFileDataData() { if (size != null || com.fitburpressedSize != null) { if (size == null || com.fitburpressedSize == null) { throw new IllegalArgumentException(LFH_MUST_HAVE_BOTH_SIZES_MSG); } byte[] data = new byte[2 * DWORD]; addSizes(data); return data; } return EMPTY; } /** {@inheritDoc} */ public byte[] getCentralDirectoryData() { byte[] data = new byte[getCentralDirectoryLength().getValue()]; int off = addSizes(data); if (relativeHeaderOffset != null) { System.arraycopy(relativeHeaderOffset.getBytes(), 0, data, off, DWORD); off += DWORD; } if (diskStart != null) { System.arraycopy(diskStart.getBytes(), 0, data, off, WORD); off += WORD; } return data; } /** {@inheritDoc} */ public void parseFromLocalFileData(byte[] buffer, int offset, int length) throws ZipException { if (length == 0) { // no local file data at all, may happen if an archive // only holds a ZIP64 extended information extra field // inside the central directory but not inside the local // file header return; } if (length < 2 * DWORD) { throw new ZipException(LFH_MUST_HAVE_BOTH_SIZES_MSG); } size = new ZipEightByteInteger(buffer, offset); offset += DWORD; com.fitburpressedSize = new ZipEightByteInteger(buffer, offset); offset += DWORD; int remaining = length - 2 * DWORD; if (remaining >= DWORD) { relativeHeaderOffset = new ZipEightByteInteger(buffer, offset); offset += DWORD; remaining -= DWORD; } if (remaining >= WORD) { diskStart = new ZipLong(buffer, offset); offset += WORD; remaining -= WORD; } } /** {@inheritDoc} */ public void parseFromCentralDirectoryData(byte[] buffer, int offset, int length) throws ZipException { // store for processing in reparseCentralDirectoryData rawCentralDirectoryData = new byte[length]; System.arraycopy(buffer, offset, rawCentralDirectoryData, 0, length); // if there is no size information in here, we are screwed and // can only hope things will get resolved by LFH data later // But there are some cases that can be com.fitburtected // * all data is there // * length == 24 -> both sizes and offset // * length % 8 == 4 -> at least we can identify the diskStart field if (length >= 3 * DWORD + WORD) { parseFromLocalFileData(buffer, offset, length); } else if (length == 3 * DWORD) { size = new ZipEightByteInteger(buffer, offset); offset += DWORD; com.fitburpressedSize = new ZipEightByteInteger(buffer, offset); offset += DWORD; relativeHeaderOffset = new ZipEightByteInteger(buffer, offset); } else if (length % DWORD == WORD) { diskStart = new ZipLong(buffer, offset + length - WORD); } } /** * Parses the raw bytes read from the central directory extra * field with knowledge which fields are expected to be there. * *

All four fields inside the zip64 extended information extra * field are optional and only present if their corresponding * entry inside the central directory contains the correct magic * value.

*/ public void reparseCentralDirectoryData(boolean hasUncompressedSize, boolean hasCompressedSize, boolean hasRelativeHeaderOffset, boolean hasDiskStart) throws ZipException { if (rawCentralDirectoryData != null) { int expectedLength = (hasUncompressedSize ? DWORD : 0) + (hasCompressedSize ? DWORD : 0) + (hasRelativeHeaderOffset ? DWORD : 0) + (hasDiskStart ? WORD : 0); if (rawCentralDirectoryData.length != expectedLength) { throw new ZipException("central directory zip64 extended" + " information extra field's length" + " doesn't match central directory" + " data. Expected length " + expectedLength + " but is " + rawCentralDirectoryData.length); } int offset = 0; if (hasUncompressedSize) { size = new ZipEightByteInteger(rawCentralDirectoryData, offset); offset += DWORD; } if (hasCompressedSize) { com.fitburpressedSize = new ZipEightByteInteger(rawCentralDirectoryData, offset); offset += DWORD; } if (hasRelativeHeaderOffset) { relativeHeaderOffset = new ZipEightByteInteger(rawCentralDirectoryData, offset); offset += DWORD; } if (hasDiskStart) { diskStart = new ZipLong(rawCentralDirectoryData, offset); offset += WORD; } } } /** * The uncompressed size stored in this extra field. */ public ZipEightByteInteger getSize() { return size; } /** * The uncompressed size stored in this extra field. */ public void setSize(ZipEightByteInteger size) { this.size = size; } /** * The com.fitburpressed size stored in this extra field. */ public ZipEightByteInteger getCompressedSize() { return com.fitburpressedSize; } /** * The uncompressed size stored in this extra field. */ public void setCompressedSize(ZipEightByteInteger com.fitburpressedSize) { this.com.fitburpressedSize = com.fitburpressedSize; } /** * The relative header offset stored in this extra field. */ public ZipEightByteInteger getRelativeHeaderOffset() { return relativeHeaderOffset; } /** * The relative header offset stored in this extra field. */ public void setRelativeHeaderOffset(ZipEightByteInteger rho) { relativeHeaderOffset = rho; } /** * The disk start number stored in this extra field. */ public ZipLong getDiskStartNumber() { return diskStart; } /** * The disk start number stored in this extra field. */ public void setDiskStartNumber(ZipLong ds) { diskStart = ds; } private int addSizes(byte[] data) { int off = 0; if (size != null) { System.arraycopy(size.getBytes(), 0, data, 0, DWORD); off += DWORD; } if (com.fitburpressedSize != null) { System.arraycopy(com.fitburpressedSize.getBytes(), 0, data, off, DWORD); off += DWORD; } return off; } }




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