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 *   https://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.io.Serializable;
022import java.nio.file.attribute.FileTime;
023import java.util.Arrays;
024import java.util.Date;
025import java.util.Objects;
026import java.util.zip.ZipException;
027
028import org.apache.commons.io.file.attribute.FileTimes;
029
030/**
031 * <p>
032 * An extra field that stores additional file and directory timestamp data for ZIP entries. Each ZIP entry can include up to three timestamps (modify, access,
033 * create*). The timestamps are stored as 32 bit signed integers representing seconds since Unix epoch (Jan 1st, 1970, UTC). This field improves on ZIP's
034 * default timestamp granularity, since it allows one to store additional timestamps, and, in addition, the timestamps are stored using per-second granularity
035 * (zip's default behavior can only store timestamps to the nearest <em>even</em> second).
036 * </p>
037 * <p>
038 * Unfortunately, 32 (signed) bits can only store dates up to the year 2037, and so this extra field will eventually be obsolete. Enjoy it while it lasts!
039 * </p>
040 * <ul>
041 * <li><strong>modifyTime:</strong> most recent time of file/directory modification (or file/dir creation if the entry has not been modified since it was
042 * created).</li>
043 * <li><strong>accessTime:</strong> most recent time file/directory was opened (for example, read from disk). Many people disable their operating systems from
044 * updating this value using the NOATIME mount option to optimize disk behavior, and thus it's not always reliable. In those cases it's always equal to
045 * modifyTime.</li>
046 * <li><strong>*createTime:</strong> modern Linux file systems (for example, ext2 and newer) do not appear to store a value like this, and so it's usually
047 * omitted altogether in the ZIP extra field. Perhaps other Unix systems track this.</li>
048 * </ul>
049 * <p>
050 * We're using the field definition given in Info-Zip's source archive: zip-3.0.tar.gz/proginfo/extrafld.txt
051 * </p>
052 *
053 * <pre>
054 * Value         Size        Description
055 * -----         ----        -----------
056 * 0x5455        Short       tag for this extra block type ("UT")
057 * TSize         Short       total data size for this block
058 * Flags         Byte        info bits
059 * (ModTime)     Long        time of last modification (UTC/GMT)
060 * (AcTime)      Long        time of last access (UTC/GMT)
061 * (CrTime)      Long        time of original creation (UTC/GMT)
062 *
063 * Central-header version:
064 *
065 * Value         Size        Description
066 * -----         ----        -----------
067 * 0x5455        Short       tag for this extra block type ("UT")
068 * TSize         Short       total data size for this block
069 * Flags         Byte        info bits (refers to local header!)
070 * (ModTime)     Long        time of last modification (UTC/GMT)
071 * </pre>
072 *
073 * @since 1.5
074 */
075public class X5455_ExtendedTimestamp implements ZipExtraField, Cloneable, Serializable {
076    private static final long serialVersionUID = 1L;
077    /**
078     * The header ID for this extra field.
079     *
080     * @since 1.23
081     */
082    public static final ZipShort HEADER_ID = new ZipShort(0x5455);
083    /**
084     * The bit set inside the flags by when the last modification time is present in this extra field.
085     */
086    public static final byte MODIFY_TIME_BIT = 1;
087    /**
088     * The bit set inside the flags by when the lasr access time is present in this extra field.
089     */
090    public static final byte ACCESS_TIME_BIT = 2;
091    /**
092     * The bit set inside the flags by when the original creation time is present in this extra field.
093     */
094    public static final byte CREATE_TIME_BIT = 4;
095
096    /**
097     * Utility method converts java.util.Date (milliseconds since epoch) into a ZipLong (seconds since epoch).
098     * <p/>
099     * Also makes sure the converted ZipLong is not too big to fit in 32 unsigned bits.
100     *
101     * @param d java.util.Date to convert to ZipLong
102     * @return ZipLong
103     */
104    private static ZipLong dateToZipLong(final Date d) {
105        if (d == null) {
106            return null;
107        }
108        return unixTimeToZipLong(d.getTime() / 1000);
109    }
110
111    /**
112     * Utility method converts {@link FileTime} into a ZipLong (seconds since epoch).
113     * <p/>
114     * Also makes sure the converted ZipLong is not too big to fit in 32 unsigned bits.
115     *
116     * @param time {@link FileTime} to convert to ZipLong
117     * @return ZipLong
118     */
119    private static ZipLong fileTimeToZipLong(final FileTime time) {
120        return time == null ? null : unixTimeToZipLong(FileTimes.toUnixTime(time));
121    }
122
123    private static FileTime unixTimeToFileTime(final ZipLong unixTime) {
124        return unixTime != null ? FileTimes.fromUnixTime(unixTime.getIntValue()) : null;
125    }
126    // The 3 boolean fields (below) come from this flag's byte. The remaining 5 bits
127    // are ignored according to the current version of the spec (December 2012).
128
129    private static ZipLong unixTimeToZipLong(final long unixTime) {
130        if (!FileTimes.isUnixTime(unixTime)) {
131            throw new IllegalArgumentException("X5455 timestamps must fit in a signed 32 bit integer: " + unixTime);
132        }
133        return new ZipLong(unixTime);
134    }
135
136    private static Date zipLongToDate(final ZipLong unixTime) {
137        return unixTime != null ? new Date(unixTime.getIntValue() * 1000L) : null;
138    }
139
140    private byte flags;
141    // Note: even if bit1 and bit2 are set, the Central data will still not contain
142    // access/create fields: only local data ever holds those! This causes
143    // some of our implementation to look a little odd, with seemingly spurious
144    // != null and length checks.
145    private boolean bit0_modifyTimePresent;
146    private boolean bit1_accessTimePresent;
147    private boolean bit2_createTimePresent;
148    private ZipLong modifyTime;
149    private ZipLong accessTime;
150    private ZipLong createTime;
151
152    /**
153     * Constructor for X5455_ExtendedTimestamp.
154     */
155    public X5455_ExtendedTimestamp() {
156    }
157
158    @Override
159    public Object clone() throws CloneNotSupportedException {
160        return super.clone();
161    }
162
163    @Override
164    public boolean equals(final Object o) {
165        if (o instanceof X5455_ExtendedTimestamp) {
166            final X5455_ExtendedTimestamp xf = (X5455_ExtendedTimestamp) o;
167            // The ZipLong==ZipLong clauses handle the cases where both are null.
168            // and only last 3 bits of flags matter.
169            return (flags & 0x07) == (xf.flags & 0x07) && Objects.equals(modifyTime, xf.modifyTime) && Objects.equals(accessTime, xf.accessTime)
170                    && Objects.equals(createTime, xf.createTime);
171        }
172        return false;
173    }
174
175    /**
176     * Gets the access time as a {@link FileTime} of this ZIP entry, or null if no such timestamp exists in the ZIP entry. The milliseconds are always zeroed
177     * out, since the underlying data offers only per-second precision.
178     *
179     * @return modify time as {@link FileTime} or null.
180     * @since 1.23
181     */
182    public FileTime getAccessFileTime() {
183        return unixTimeToFileTime(accessTime);
184    }
185
186    /**
187     * Gets the access time as a java.util.Date of this ZIP entry, or null if no such timestamp exists in the ZIP entry. The milliseconds are always zeroed out,
188     * since the underlying data offers only per-second precision.
189     *
190     * @return access time as java.util.Date or null.
191     */
192    public Date getAccessJavaTime() {
193        return zipLongToDate(accessTime);
194    }
195
196    /**
197     * Gets the access time (seconds since epoch) of this ZIP entry as a ZipLong object, or null if no such timestamp exists in the ZIP entry.
198     *
199     * @return access time (seconds since epoch) or null.
200     */
201    public ZipLong getAccessTime() {
202        return accessTime;
203    }
204
205    /**
206     * Gets the actual data to put into central directory data - without Header-ID or length specifier.
207     *
208     * @return the central directory data
209     */
210    @Override
211    public byte[] getCentralDirectoryData() {
212        // Truncate out create & access time (last 8 bytes) from
213        // the copy of the local data we obtained:
214        return Arrays.copyOf(getLocalFileDataData(), getCentralDirectoryLength().getValue());
215    }
216
217    /**
218     * Gets the length of the extra field in the local file data - without Header-ID or length specifier.
219     *
220     * <p>
221     * For X5455 the central length is often smaller than the local length, because central cannot contain access or create timestamps.
222     * </p>
223     *
224     * @return a {@code ZipShort} for the length of the data of this extra field
225     */
226    @Override
227    public ZipShort getCentralDirectoryLength() {
228        return new ZipShort(1 + (bit0_modifyTimePresent ? 4 : 0));
229    }
230
231    /**
232     * Gets the create time as a {@link FileTime} of this ZIP entry, or null if no such timestamp exists in the ZIP entry. The milliseconds are always zeroed
233     * out, since the underlying data offers only per-second precision.
234     *
235     * @return modify time as {@link FileTime} or null.
236     * @since 1.23
237     */
238    public FileTime getCreateFileTime() {
239        return unixTimeToFileTime(createTime);
240    }
241
242    /**
243     * <p>
244     * Gets the create time as a java.util.Date of this ZIP entry, or null if no such timestamp exists in the ZIP entry. The milliseconds are always zeroed out,
245     * since the underlying data offers only per-second precision.
246     * </p>
247     * <p>
248     * Note: modern Linux file systems (for example, ext2) do not appear to store a "create time" value, and so it's usually omitted altogether in the ZIP extra
249     * field. Perhaps other Unix systems track this.
250     * </p>
251     *
252     * @return create time as java.util.Date or null.
253     */
254    public Date getCreateJavaTime() {
255        return zipLongToDate(createTime);
256    }
257
258    /**
259     * <p>
260     * Gets the create time (seconds since epoch) of this ZIP entry as a ZipLong object, or null if no such timestamp exists in the ZIP entry.
261     * </p>
262     * <p>
263     * Note: modern Linux file systems (for example, ext2) do not appear to store a "create time" value, and so it's usually omitted altogether in the ZIP extra
264     * field. Perhaps other Unix systems track this.
265     * </p>
266     *
267     * @return create time (seconds since epoch) or null.
268     */
269    public ZipLong getCreateTime() {
270        return createTime;
271    }
272
273    /**
274     * Gets flags byte. The flags byte tells us which of the three datestamp fields are present in the data:
275     *
276     * <pre>
277     * bit0 - modify time
278     * bit1 - access time
279     * bit2 - create time
280     * </pre>
281     *
282     * Only first 3 bits of flags are used according to the latest version of the spec (December 2012).
283     *
284     * @return flags byte indicating which of the three datestamp fields are present.
285     */
286    public byte getFlags() {
287        return flags;
288    }
289
290    /**
291     * Gets the Header-ID.
292     *
293     * @return the value for the header id for this extrafield
294     */
295    @Override
296    public ZipShort getHeaderId() {
297        return HEADER_ID;
298    }
299
300    /**
301     * Gets the actual data to put into local file data - without Header-ID or length specifier.
302     *
303     * @return get the data
304     */
305    @Override
306    public byte[] getLocalFileDataData() {
307        final byte[] data = new byte[getLocalFileDataLength().getValue()];
308        int pos = 0;
309        data[pos++] = 0;
310        if (bit0_modifyTimePresent) {
311            data[0] |= MODIFY_TIME_BIT;
312            System.arraycopy(modifyTime.getBytes(), 0, data, pos, 4);
313            pos += 4;
314        }
315        if (bit1_accessTimePresent && accessTime != null) {
316            data[0] |= ACCESS_TIME_BIT;
317            System.arraycopy(accessTime.getBytes(), 0, data, pos, 4);
318            pos += 4;
319        }
320        if (bit2_createTimePresent && createTime != null) {
321            data[0] |= CREATE_TIME_BIT;
322            System.arraycopy(createTime.getBytes(), 0, data, pos, 4);
323            pos += 4; // NOSONAR - assignment as documentation
324        }
325        return data;
326    }
327
328    /**
329     * Gets the length of the extra field in the local file data - without Header-ID or length specifier.
330     *
331     * @return a {@code ZipShort} for the length of the data of this extra field
332     */
333    @Override
334    public ZipShort getLocalFileDataLength() {
335        return new ZipShort(1 + (bit0_modifyTimePresent ? 4 : 0) + (bit1_accessTimePresent && accessTime != null ? 4 : 0)
336                + (bit2_createTimePresent && createTime != null ? 4 : 0));
337    }
338
339    /**
340     * Gets the modify time as a {@link FileTime} of this ZIP entry, or null if no such timestamp exists in the ZIP entry. The milliseconds are always zeroed
341     * out, since the underlying data offers only per-second precision.
342     *
343     * @return modify time as {@link FileTime} or null.
344     * @since 1.23
345     */
346    public FileTime getModifyFileTime() {
347        return unixTimeToFileTime(modifyTime);
348    }
349
350    /**
351     * Gets the modify time as a java.util.Date of this ZIP entry, or null if no such timestamp exists in the ZIP entry. The milliseconds are always zeroed out,
352     * since the underlying data offers only per-second precision.
353     *
354     * @return modify time as java.util.Date or null.
355     */
356    public Date getModifyJavaTime() {
357        return zipLongToDate(modifyTime);
358    }
359
360    /**
361     * Gets the modify time (seconds since epoch) of this ZIP entry as a ZipLong object, or null if no such timestamp exists in the ZIP entry.
362     *
363     * @return modify time (seconds since epoch) or null.
364     */
365    public ZipLong getModifyTime() {
366        return modifyTime;
367    }
368
369    @Override
370    public int hashCode() {
371        int hc = -123 * (flags & 0x07); // only last 3 bits of flags matter
372        if (modifyTime != null) {
373            hc ^= modifyTime.hashCode();
374        }
375        if (accessTime != null) {
376            // Since accessTime is often same as modifyTime,
377            // this prevents them from XOR negating each other.
378            hc ^= Integer.rotateLeft(accessTime.hashCode(), 11);
379        }
380        if (createTime != null) {
381            hc ^= Integer.rotateLeft(createTime.hashCode(), 22);
382        }
383        return hc;
384    }
385
386    /**
387     * Tests whether bit0 of the flags byte is set or not, which should correspond to the presence or absence of a modify timestamp in this particular ZIP
388     * entry.
389     *
390     * @return true if bit0 of the flags byte is set.
391     */
392    public boolean isBit0_modifyTimePresent() {
393        return bit0_modifyTimePresent;
394    }
395
396    /**
397     * Tests whether bit1 of the flags byte is set or not, which should correspond to the presence or absence of a "last access" timestamp in this particular
398     * ZIP entry.
399     *
400     * @return true if bit1 of the flags byte is set.
401     */
402    public boolean isBit1_accessTimePresent() {
403        return bit1_accessTimePresent;
404    }
405
406    /**
407     * Tests whether bit2 of the flags byte is set or not, which should correspond to the presence or absence of a create timestamp in this particular ZIP
408     * entry.
409     *
410     * @return true if bit2 of the flags byte is set.
411     */
412    public boolean isBit2_createTimePresent() {
413        return bit2_createTimePresent;
414    }
415
416    /**
417     * Doesn't do anything special since this class always uses the same parsing logic for both central directory and local file data.
418     */
419    @Override
420    public void parseFromCentralDirectoryData(final byte[] buffer, final int offset, final int length) throws ZipException {
421        reset();
422        parseFromLocalFileData(buffer, offset, length);
423    }
424
425    /**
426     * Populate data from this array as if it was in local file data.
427     *
428     * @param data   an array of bytes
429     * @param offset the start offset
430     * @param length the number of bytes in the array from offset
431     * @throws java.util.zip.ZipException on error
432     */
433    @Override
434    public void parseFromLocalFileData(final byte[] data, int offset, final int length) throws ZipException {
435        reset();
436        if (length < 1) {
437            throw new ZipException("X5455_ExtendedTimestamp too short, only " + length + " bytes");
438        }
439        final int len = offset + length;
440        setFlags(data[offset++]);
441        if (bit0_modifyTimePresent && offset + 4 <= len) {
442            modifyTime = new ZipLong(data, offset);
443            offset += 4;
444        } else {
445            bit0_modifyTimePresent = false;
446        }
447        if (bit1_accessTimePresent && offset + 4 <= len) {
448            accessTime = new ZipLong(data, offset);
449            offset += 4;
450        } else {
451            bit1_accessTimePresent = false;
452        }
453        if (bit2_createTimePresent && offset + 4 <= len) {
454            createTime = new ZipLong(data, offset);
455            offset += 4; // NOSONAR - assignment as documentation
456        } else {
457            bit2_createTimePresent = false;
458        }
459    }
460
461    /**
462     * Reset state back to newly constructed state. Helps us make sure parse() calls always generate clean results.
463     */
464    private void reset() {
465        setFlags((byte) 0);
466        this.modifyTime = null;
467        this.accessTime = null;
468        this.createTime = null;
469    }
470
471    /**
472     * <p>
473     * Sets the acccess time as a {@link FileTime} of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
474     * </p>
475     * <p>
476     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
477     * flags is also set.
478     * </p>
479     *
480     * @param time access time as {@link FileTime}
481     * @since 1.23
482     */
483    public void setAccessFileTime(final FileTime time) {
484        setAccessTime(fileTimeToZipLong(time));
485    }
486
487    /**
488     * <p>
489     * Sets the access time as a java.util.Date of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
490     * </p>
491     * <p>
492     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
493     * flags is also set.
494     * </p>
495     *
496     * @param d access time as java.util.Date
497     */
498    public void setAccessJavaTime(final Date d) {
499        setAccessTime(dateToZipLong(d));
500    }
501
502    /**
503     * <p>
504     * Sets the access time (seconds since epoch) of this ZIP entry using a ZipLong object
505     * </p>
506     * <p>
507     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
508     * flags is also set.
509     * </p>
510     *
511     * @param l ZipLong of the access time (seconds per epoch)
512     */
513    public void setAccessTime(final ZipLong l) {
514        bit1_accessTimePresent = l != null;
515        flags = (byte) (l != null ? flags | ACCESS_TIME_BIT : flags & ~ACCESS_TIME_BIT);
516        this.accessTime = l;
517    }
518
519    /**
520     * <p>
521     * Sets the create time as a {@link FileTime} of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
522     * </p>
523     * <p>
524     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
525     * flags is also set.
526     * </p>
527     *
528     * @param time create time as {@link FileTime}
529     * @since 1.23
530     */
531    public void setCreateFileTime(final FileTime time) {
532        setCreateTime(fileTimeToZipLong(time));
533    }
534
535    /**
536     * <p>
537     * Sets the create time as a java.util.Date of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
538     * </p>
539     * <p>
540     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
541     * flags is also set.
542     * </p>
543     *
544     * @param d create time as java.util.Date
545     */
546    public void setCreateJavaTime(final Date d) {
547        setCreateTime(dateToZipLong(d));
548    }
549
550    /**
551     * <p>
552     * Sets the create time (seconds since epoch) of this ZIP entry using a ZipLong object
553     * </p>
554     * <p>
555     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
556     * flags is also set.
557     * </p>
558     *
559     * @param l ZipLong of the create time (seconds per epoch)
560     */
561    public void setCreateTime(final ZipLong l) {
562        bit2_createTimePresent = l != null;
563        flags = (byte) (l != null ? flags | CREATE_TIME_BIT : flags & ~CREATE_TIME_BIT);
564        this.createTime = l;
565    }
566
567    /**
568     * Sets flags byte. The flags byte tells us which of the three datestamp fields are present in the data:
569     *
570     * <pre>
571     * bit0 - modify time
572     * bit1 - access time
573     * bit2 - create time
574     * </pre>
575     *
576     * Only first 3 bits of flags are used according to the latest version of the spec (December 2012).
577     *
578     * @param flags flags byte indicating which of the three datestamp fields are present.
579     */
580    public void setFlags(final byte flags) {
581        this.flags = flags;
582        this.bit0_modifyTimePresent = (flags & MODIFY_TIME_BIT) == MODIFY_TIME_BIT;
583        this.bit1_accessTimePresent = (flags & ACCESS_TIME_BIT) == ACCESS_TIME_BIT;
584        this.bit2_createTimePresent = (flags & CREATE_TIME_BIT) == CREATE_TIME_BIT;
585    }
586
587    /**
588     * <p>
589     * Sets the modify time as a {@link FileTime} of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
590     * </p>
591     * <p>
592     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
593     * flags is also set.
594     * </p>
595     *
596     * @param time modify time as {@link FileTime}
597     * @since 1.23
598     */
599    public void setModifyFileTime(final FileTime time) {
600        setModifyTime(fileTimeToZipLong(time));
601    }
602
603    /**
604     * <p>
605     * Sets the modify time as a java.util.Date of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
606     * </p>
607     * <p>
608     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
609     * flags is also set.
610     * </p>
611     *
612     * @param d modify time as java.util.Date
613     */
614    public void setModifyJavaTime(final Date d) {
615        setModifyTime(dateToZipLong(d));
616    }
617
618    /**
619     * <p>
620     * Sets the modify time (seconds since epoch) of this ZIP entry using a ZipLong object.
621     * </p>
622     * <p>
623     * Note: the setters for flags and timestamps are decoupled. Even if the timestamp is not-null, it will only be written out if the corresponding bit in the
624     * flags is also set.
625     * </p>
626     *
627     * @param l ZipLong of the modify time (seconds per epoch)
628     */
629    public void setModifyTime(final ZipLong l) {
630        bit0_modifyTimePresent = l != null;
631        flags = (byte) (l != null ? flags | MODIFY_TIME_BIT : flags & ~MODIFY_TIME_BIT);
632        this.modifyTime = l;
633    }
634
635    /**
636     * Returns a String representation of this class useful for debugging purposes.
637     *
638     * @return A String representation of this class useful for debugging purposes.
639     */
640    @Override
641    public String toString() {
642        final StringBuilder buf = new StringBuilder();
643        buf.append("0x5455 Zip Extra Field: Flags=");
644        buf.append(Integer.toBinaryString(ZipUtil.unsignedIntToSignedByte(flags))).append(" ");
645        if (bit0_modifyTimePresent && modifyTime != null) {
646            final Date m = getModifyJavaTime();
647            buf.append(" Modify:[").append(m).append("] ");
648        }
649        if (bit1_accessTimePresent && accessTime != null) {
650            final Date a = getAccessJavaTime();
651            buf.append(" Access:[").append(a).append("] ");
652        }
653        if (bit2_createTimePresent && createTime != null) {
654            final Date c = getCreateJavaTime();
655            buf.append(" Create:[").append(c).append("] ");
656        }
657        return buf.toString();
658    }
659}