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
023import static org.apache.commons.compress.archivers.zip.ZipConstants.DWORD;
024import static org.apache.commons.compress.archivers.zip.ZipConstants.WORD;
025
026/**
027 * Holds size and other extended information for entries that use Zip64
028 * features.
029 *
030 * <p>Currently Commons Compress doesn't support encrypting the
031 * central directory so the note in APPNOTE.TXT about masking doesn't
032 * apply.</p>
033 *
034 * <p>The implementation relies on data being read from the local file
035 * header and assumes that both size values are always present.</p>
036 *
037 * @see <a href="http://www.pkware.com/documents/casestudies/APPNOTE.TXT">PKWARE
038 * APPNOTE.TXT, section 4.5.3</a>
039 *
040 * @since 1.2
041 * @NotThreadSafe
042 */
043public class Zip64ExtendedInformationExtraField implements ZipExtraField {
044
045    static final ZipShort HEADER_ID = new ZipShort(0x0001);
046
047    private static final String LFH_MUST_HAVE_BOTH_SIZES_MSG =
048        "Zip64 extended information must contain"
049        + " both size values in the local file header.";
050    private static final byte[] EMPTY = new byte[0];
051
052    private ZipEightByteInteger size, compressedSize, relativeHeaderOffset;
053    private ZipLong diskStart;
054
055    /**
056     * Stored in {@link #parseFromCentralDirectoryData
057     * parseFromCentralDirectoryData} so it can be reused when ZipFile
058     * calls {@link #reparseCentralDirectoryData
059     * reparseCentralDirectoryData}.
060     *
061     * <p>Not used for anything else</p>
062     *
063     * @since 1.3
064     */
065    private byte[] rawCentralDirectoryData;
066
067    /**
068     * This constructor should only be used by the code that reads
069     * archives inside of Commons Compress.
070     */
071    public Zip64ExtendedInformationExtraField() { }
072
073    /**
074     * Creates an extra field based on the original and compressed size.
075     *
076     * @param size the entry's original size
077     * @param compressedSize the entry's compressed size
078     *
079     * @throws IllegalArgumentException if size or compressedSize is null
080     */
081    public Zip64ExtendedInformationExtraField(ZipEightByteInteger size,
082                                              ZipEightByteInteger compressedSize) {
083        this(size, compressedSize, null, null);
084    }
085
086    /**
087     * Creates an extra field based on all four possible values.
088     *
089     * @param size the entry's original size
090     * @param compressedSize the entry's compressed size
091     * @param relativeHeaderOffset the entry's offset
092     * @param diskStart the disk start
093     *
094     * @throws IllegalArgumentException if size or compressedSize is null
095     */
096    public Zip64ExtendedInformationExtraField(ZipEightByteInteger size,
097                                              ZipEightByteInteger compressedSize,
098                                              ZipEightByteInteger relativeHeaderOffset,
099                                              ZipLong diskStart) {
100        this.size = size;
101        this.compressedSize = compressedSize;
102        this.relativeHeaderOffset = relativeHeaderOffset;
103        this.diskStart = diskStart;
104    }
105
106    public ZipShort getHeaderId() {
107        return HEADER_ID;
108    }
109
110    public ZipShort getLocalFileDataLength() {
111        return new ZipShort(size != null ? 2 * DWORD : 0);
112    }
113
114    public ZipShort getCentralDirectoryLength() {
115        return new ZipShort((size != null ? DWORD : 0)
116                            + (compressedSize != null ? DWORD : 0)
117                            + (relativeHeaderOffset != null ? DWORD : 0)
118                            + (diskStart != null ? WORD : 0));
119    }
120
121    public byte[] getLocalFileDataData() {
122        if (size != null || compressedSize != null) {
123            if (size == null || compressedSize == null) {
124                throw new IllegalArgumentException(LFH_MUST_HAVE_BOTH_SIZES_MSG);
125            }
126            byte[] data = new byte[2 * DWORD];
127            addSizes(data);
128            return data;
129        }
130        return EMPTY;
131    }
132
133    public byte[] getCentralDirectoryData() {
134        byte[] data = new byte[getCentralDirectoryLength().getValue()];
135        int off = addSizes(data);
136        if (relativeHeaderOffset != null) {
137            System.arraycopy(relativeHeaderOffset.getBytes(), 0, data, off, DWORD);
138            off += DWORD;
139        }
140        if (diskStart != null) {
141            System.arraycopy(diskStart.getBytes(), 0, data, off, WORD);
142            off += WORD;
143        }
144        return data;
145    }
146
147    public void parseFromLocalFileData(byte[] buffer, int offset, int length)
148        throws ZipException {
149        if (length == 0) {
150            // no local file data at all, may happen if an archive
151            // only holds a ZIP64 extended information extra field
152            // inside the central directory but not inside the local
153            // file header
154            return;
155        }
156        if (length < 2 * DWORD) {
157            throw new ZipException(LFH_MUST_HAVE_BOTH_SIZES_MSG);
158        }
159        size = new ZipEightByteInteger(buffer, offset);
160        offset += DWORD;
161        compressedSize = new ZipEightByteInteger(buffer, offset);
162        offset += DWORD;
163        int remaining = length - 2 * DWORD;
164        if (remaining >= DWORD) {
165            relativeHeaderOffset = new ZipEightByteInteger(buffer, offset);
166            offset += DWORD;
167            remaining -= DWORD;
168        }
169        if (remaining >= WORD) {
170            diskStart = new ZipLong(buffer, offset);
171            offset += WORD;
172            remaining -= WORD;
173        }
174    }
175
176    public void parseFromCentralDirectoryData(byte[] buffer, int offset,
177                                              int length)
178        throws ZipException {
179        // store for processing in reparseCentralDirectoryData
180        rawCentralDirectoryData = new byte[length];
181        System.arraycopy(buffer, offset, rawCentralDirectoryData, 0, length);
182
183        // if there is no size information in here, we are screwed and
184        // can only hope things will get resolved by LFH data later
185        // But there are some cases that can be detected
186        // * all data is there
187        // * length == 24 -> both sizes and offset
188        // * length % 8 == 4 -> at least we can identify the diskStart field
189        if (length >= 3 * DWORD + WORD) {
190            parseFromLocalFileData(buffer, offset, length);
191        } else if (length == 3 * DWORD) {
192            size = new ZipEightByteInteger(buffer, offset);
193            offset += DWORD;
194            compressedSize = new ZipEightByteInteger(buffer, offset);
195            offset += DWORD;
196            relativeHeaderOffset = new ZipEightByteInteger(buffer, offset);
197        } else if (length % DWORD == WORD) {
198            diskStart = new ZipLong(buffer, offset + length - WORD);
199        }
200    }
201
202    /**
203     * Parses the raw bytes read from the central directory extra
204     * field with knowledge which fields are expected to be there.
205     *
206     * <p>All four fields inside the zip64 extended information extra
207     * field are optional and must only be present if their corresponding
208     * entry inside the central directory contains the correct magic
209     * value.</p>
210     *
211     * @param hasUncompressedSize flag to read from central directory
212     * @param hasCompressedSize flag to read from central directory
213     * @param hasRelativeHeaderOffset flag to read from central directory
214     * @param hasDiskStart flag to read from central directory
215     * @throws ZipException on error
216     */
217    public void reparseCentralDirectoryData(boolean hasUncompressedSize,
218                                            boolean hasCompressedSize,
219                                            boolean hasRelativeHeaderOffset,
220                                            boolean hasDiskStart)
221        throws ZipException {
222        if (rawCentralDirectoryData != null) {
223            int expectedLength = (hasUncompressedSize ? DWORD : 0)
224                + (hasCompressedSize ? DWORD : 0)
225                + (hasRelativeHeaderOffset ? DWORD : 0)
226                + (hasDiskStart ? WORD : 0);
227            if (rawCentralDirectoryData.length < expectedLength) {
228                throw new ZipException("central directory zip64 extended"
229                                       + " information extra field's length"
230                                       + " doesn't match central directory"
231                                       + " data.  Expected length "
232                                       + expectedLength + " but is "
233                                       + rawCentralDirectoryData.length);
234            }
235            int offset = 0;
236            if (hasUncompressedSize) {
237                size = new ZipEightByteInteger(rawCentralDirectoryData, offset);
238                offset += DWORD;
239            }
240            if (hasCompressedSize) {
241                compressedSize = new ZipEightByteInteger(rawCentralDirectoryData,
242                                                         offset);
243                offset += DWORD;
244            }
245            if (hasRelativeHeaderOffset) {
246                relativeHeaderOffset =
247                    new ZipEightByteInteger(rawCentralDirectoryData, offset);
248                offset += DWORD;
249            }
250            if (hasDiskStart) {
251                diskStart = new ZipLong(rawCentralDirectoryData, offset);
252                offset += WORD;
253            }
254        }
255    }
256
257    /**
258     * The uncompressed size stored in this extra field.
259     * @return The uncompressed size stored in this extra field.
260     */
261    public ZipEightByteInteger getSize() {
262        return size;
263    }
264
265    /**
266     * The uncompressed size stored in this extra field.
267     * @param size The uncompressed size stored in this extra field.
268     */
269    public void setSize(ZipEightByteInteger size) {
270        this.size = size;
271    }
272
273    /**
274     * The compressed size stored in this extra field.
275     * @return The compressed size stored in this extra field.
276     */
277    public ZipEightByteInteger getCompressedSize() {
278        return compressedSize;
279    }
280
281    /**
282     * The uncompressed size stored in this extra field.
283     * @param compressedSize The uncompressed size stored in this extra field.
284     */
285    public void setCompressedSize(ZipEightByteInteger compressedSize) {
286        this.compressedSize = compressedSize;
287    }
288
289    /**
290     * The relative header offset stored in this extra field.
291     * @return The relative header offset stored in this extra field.
292     */
293    public ZipEightByteInteger getRelativeHeaderOffset() {
294        return relativeHeaderOffset;
295    }
296
297    /**
298     * The relative header offset stored in this extra field.
299     * @param rho The relative header offset stored in this extra field.
300     */
301    public void setRelativeHeaderOffset(ZipEightByteInteger rho) {
302        relativeHeaderOffset = rho;
303    }
304
305    /**
306     * The disk start number stored in this extra field.
307     * @return The disk start number stored in this extra field.
308     */
309    public ZipLong getDiskStartNumber() {
310        return diskStart;
311    }
312
313    /**
314     * The disk start number stored in this extra field.
315     * @param ds The disk start number stored in this extra field.
316     */
317    public void setDiskStartNumber(ZipLong ds) {
318        diskStart = ds;
319    }
320
321    private int addSizes(byte[] data) {
322        int off = 0;
323        if (size != null) {
324            System.arraycopy(size.getBytes(), 0, data, 0, DWORD);
325            off += DWORD;
326        }
327        if (compressedSize != null) {
328            System.arraycopy(compressedSize.getBytes(), 0, data, off, DWORD);
329            off += DWORD;
330        }
331        return off;
332    }
333}