1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.commons.compress.archivers.zip;
20
21 import java.io.Serializable;
22 import java.nio.file.attribute.FileTime;
23 import java.util.Arrays;
24 import java.util.Date;
25 import java.util.Objects;
26 import java.util.zip.ZipException;
27
28 import org.apache.commons.compress.utils.TimeUtils;
29 import org.apache.commons.io.file.attribute.FileTimes;
30
31 /**
32 * <p>
33 * 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,
34 * 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
35 * default timestamp granularity, since it allows one to store additional timestamps, and, in addition, the timestamps are stored using per-second granularity
36 * (zip's default behavior can only store timestamps to the nearest <em>even</em> second).
37 * </p>
38 * <p>
39 * 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!
40 * </p>
41 * <ul>
42 * <li><b>modifyTime:</b> most recent time of file/directory modification (or file/dir creation if the entry has not been modified since it was created).</li>
43 * <li><b>accessTime:</b> most recent time file/directory was opened (e.g., read from disk). Many people disable their operating systems from updating this
44 * 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 modifyTime.</li>
45 * <li><b>*createTime:</b> modern Linux file systems (e.g., ext2 and newer) do not appear to store a value like this, and so it's usually omitted altogether in
46 * the ZIP extra field. Perhaps other UNIX systems track this.</li>
47 * </ul>
48 * <p>
49 * We're using the field definition given in Info-Zip's source archive: zip-3.0.tar.gz/proginfo/extrafld.txt
50 * </p>
51 *
52 * <pre>
53 * Value Size Description
54 * ----- ---- -----------
55 * 0x5455 Short tag for this extra block type ("UT")
56 * TSize Short total data size for this block
57 * Flags Byte info bits
58 * (ModTime) Long time of last modification (UTC/GMT)
59 * (AcTime) Long time of last access (UTC/GMT)
60 * (CrTime) Long time of original creation (UTC/GMT)
61 *
62 * Central-header version:
63 *
64 * Value Size Description
65 * ----- ---- -----------
66 * 0x5455 Short tag for this extra block type ("UT")
67 * TSize Short total data size for this block
68 * Flags Byte info bits (refers to local header!)
69 * (ModTime) Long time of last modification (UTC/GMT)
70 * </pre>
71 *
72 * @since 1.5
73 */
74 public class X5455_ExtendedTimestamp implements ZipExtraField, Cloneable, Serializable {
75 private static final long serialVersionUID = 1L;
76
77 /**
78 * The header ID for this extra field.
79 *
80 * @since 1.23
81 */
82 public static final ZipShort HEADER_ID = new ZipShort(0x5455);
83
84 /**
85 * The bit set inside the flags by when the last modification time is present in this extra field.
86 */
87 public static final byte MODIFY_TIME_BIT = 1;
88 /**
89 * The bit set inside the flags by when the lasr access time is present in this extra field.
90 */
91 public static final byte ACCESS_TIME_BIT = 2;
92 /**
93 * The bit set inside the flags by when the original creation time is present in this extra field.
94 */
95 public static final byte CREATE_TIME_BIT = 4;
96
97 /**
98 * Utility method converts java.util.Date (milliseconds since epoch) into a ZipLong (seconds since epoch).
99 * <p/>
100 * Also makes sure the converted ZipLong is not too big to fit in 32 unsigned bits.
101 *
102 * @param d java.util.Date to convert to ZipLong
103 * @return ZipLong
104 */
105 private static ZipLong dateToZipLong(final Date d) {
106 if (d == null) {
107 return null;
108 }
109 return unixTimeToZipLong(d.getTime() / 1000);
110 }
111
112 /**
113 * Utility method converts {@link FileTime} into a ZipLong (seconds since epoch).
114 * <p/>
115 * Also makes sure the converted ZipLong is not too big to fit in 32 unsigned bits.
116 *
117 * @param time {@link FileTime} to convert to ZipLong
118 * @return ZipLong
119 */
120 private static ZipLong fileTimeToZipLong(final FileTime time) {
121 return time == null ? null : unixTimeToZipLong(TimeUtils.toUnixTime(time));
122 }
123
124 private static FileTime unixTimeToFileTime(final ZipLong unixTime) {
125 return unixTime != null ? FileTimes.fromUnixTime(unixTime.getIntValue()) : null;
126 }
127 // The 3 boolean fields (below) come from this flag's byte. The remaining 5 bits
128 // are ignored according to the current version of the spec (December 2012).
129
130 private static ZipLong unixTimeToZipLong(final long unixTime) {
131 if (!FileTimes.isUnixTime(unixTime)) {
132 throw new IllegalArgumentException("X5455 timestamps must fit in a signed 32 bit integer: " + unixTime);
133 }
134 return new ZipLong(unixTime);
135 }
136
137 private static Date zipLongToDate(final ZipLong unixTime) {
138 return unixTime != null ? new Date(unixTime.getIntValue() * 1000L) : null;
139 }
140
141 private byte flags;
142 // Note: even if bit1 and bit2 are set, the Central data will still not contain
143 // access/create fields: only local data ever holds those! This causes
144 // some of our implementation to look a little odd, with seemingly spurious
145 // != null and length checks.
146 private boolean bit0_modifyTimePresent;
147 private boolean bit1_accessTimePresent;
148
149 private boolean bit2_createTimePresent;
150
151 private ZipLong modifyTime;
152
153 private ZipLong accessTime;
154
155 private ZipLong createTime;
156
157 /**
158 * Constructor for X5455_ExtendedTimestamp.
159 */
160 public X5455_ExtendedTimestamp() {
161 }
162
163 @Override
164 public Object clone() throws CloneNotSupportedException {
165 return super.clone();
166 }
167
168 @Override
169 public boolean equals(final Object o) {
170 if (o instanceof X5455_ExtendedTimestamp) {
171 final X5455_ExtendedTimestamp xf = (X5455_ExtendedTimestamp) o;
172
173 // The ZipLong==ZipLong clauses handle the cases where both are null.
174 // and only last 3 bits of flags matter.
175 return (flags & 0x07) == (xf.flags & 0x07) && Objects.equals(modifyTime, xf.modifyTime) && Objects.equals(accessTime, xf.accessTime)
176 && Objects.equals(createTime, xf.createTime);
177 }
178 return false;
179 }
180
181 /**
182 * 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
183 * out, since the underlying data offers only per-second precision.
184 *
185 * @return modify time as {@link FileTime} or null.
186 * @since 1.23
187 */
188 public FileTime getAccessFileTime() {
189 return unixTimeToFileTime(accessTime);
190 }
191
192 /**
193 * 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,
194 * since the underlying data offers only per-second precision.
195 *
196 * @return access time as java.util.Date or null.
197 */
198 public Date getAccessJavaTime() {
199 return zipLongToDate(accessTime);
200 }
201
202 /**
203 * 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.
204 *
205 * @return access time (seconds since epoch) or null.
206 */
207 public ZipLong getAccessTime() {
208 return accessTime;
209 }
210
211 /**
212 * Gets the actual data to put into central directory data - without Header-ID or length specifier.
213 *
214 * @return the central directory data
215 */
216 @Override
217 public byte[] getCentralDirectoryData() {
218 // Truncate out create & access time (last 8 bytes) from
219 // the copy of the local data we obtained:
220 return Arrays.copyOf(getLocalFileDataData(), getCentralDirectoryLength().getValue());
221 }
222
223 /**
224 * Gets the length of the extra field in the local file data - without Header-ID or length specifier.
225 *
226 * <p>
227 * For X5455 the central length is often smaller than the local length, because central cannot contain access or create timestamps.
228 * </p>
229 *
230 * @return a {@code ZipShort} for the length of the data of this extra field
231 */
232 @Override
233 public ZipShort getCentralDirectoryLength() {
234 return new ZipShort(1 + (bit0_modifyTimePresent ? 4 : 0));
235 }
236
237 /**
238 * 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
239 * out, since the underlying data offers only per-second precision.
240 *
241 * @return modify time as {@link FileTime} or null.
242 * @since 1.23
243 */
244 public FileTime getCreateFileTime() {
245 return unixTimeToFileTime(createTime);
246 }
247
248 /**
249 * <p>
250 * 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,
251 * since the underlying data offers only per-second precision.
252 * </p>
253 * <p>
254 * Note: modern Linux file systems (e.g., ext2) do not appear to store a "create time" value, and so it's usually omitted altogether in the ZIP extra field.
255 * Perhaps other UNIX systems track this.
256 * </p>
257 *
258 * @return create time as java.util.Date or null.
259 */
260 public Date getCreateJavaTime() {
261 return zipLongToDate(createTime);
262 }
263
264 /**
265 * <p>
266 * 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.
267 * </p>
268 * <p>
269 * Note: modern Linux file systems (e.g., ext2) do not appear to store a "create time" value, and so it's usually omitted altogether in the ZIP extra field.
270 * Perhaps other UNIX systems track this.
271 * </p>
272 *
273 * @return create time (seconds since epoch) or null.
274 */
275 public ZipLong getCreateTime() {
276 return createTime;
277 }
278
279 /**
280 * Gets flags byte. The flags byte tells us which of the three datestamp fields are present in the data:
281 *
282 * <pre>
283 * bit0 - modify time
284 * bit1 - access time
285 * bit2 - create time
286 * </pre>
287 *
288 * Only first 3 bits of flags are used according to the latest version of the spec (December 2012).
289 *
290 * @return flags byte indicating which of the three datestamp fields are present.
291 */
292 public byte getFlags() {
293 return flags;
294 }
295
296 /**
297 * Gets the Header-ID.
298 *
299 * @return the value for the header id for this extrafield
300 */
301 @Override
302 public ZipShort getHeaderId() {
303 return HEADER_ID;
304 }
305
306 /**
307 * Gets the actual data to put into local file data - without Header-ID or length specifier.
308 *
309 * @return get the data
310 */
311 @Override
312 public byte[] getLocalFileDataData() {
313 final byte[] data = new byte[getLocalFileDataLength().getValue()];
314 int pos = 0;
315 data[pos++] = 0;
316 if (bit0_modifyTimePresent) {
317 data[0] |= MODIFY_TIME_BIT;
318 System.arraycopy(modifyTime.getBytes(), 0, data, pos, 4);
319 pos += 4;
320 }
321 if (bit1_accessTimePresent && accessTime != null) {
322 data[0] |= ACCESS_TIME_BIT;
323 System.arraycopy(accessTime.getBytes(), 0, data, pos, 4);
324 pos += 4;
325 }
326 if (bit2_createTimePresent && createTime != null) {
327 data[0] |= CREATE_TIME_BIT;
328 System.arraycopy(createTime.getBytes(), 0, data, pos, 4);
329 pos += 4; // NOSONAR - assignment as documentation
330 }
331 return data;
332 }
333
334 /**
335 * Gets the length of the extra field in the local file data - without Header-ID or length specifier.
336 *
337 * @return a {@code ZipShort} for the length of the data of this extra field
338 */
339 @Override
340 public ZipShort getLocalFileDataLength() {
341 return new ZipShort(1 + (bit0_modifyTimePresent ? 4 : 0) + (bit1_accessTimePresent && accessTime != null ? 4 : 0)
342 + (bit2_createTimePresent && createTime != null ? 4 : 0));
343 }
344
345 /**
346 * 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
347 * out, since the underlying data offers only per-second precision.
348 *
349 * @return modify time as {@link FileTime} or null.
350 * @since 1.23
351 */
352 public FileTime getModifyFileTime() {
353 return unixTimeToFileTime(modifyTime);
354 }
355
356 /**
357 * 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,
358 * since the underlying data offers only per-second precision.
359 *
360 * @return modify time as java.util.Date or null.
361 */
362 public Date getModifyJavaTime() {
363 return zipLongToDate(modifyTime);
364 }
365
366 /**
367 * 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.
368 *
369 * @return modify time (seconds since epoch) or null.
370 */
371 public ZipLong getModifyTime() {
372 return modifyTime;
373 }
374
375 @Override
376 public int hashCode() {
377 int hc = -123 * (flags & 0x07); // only last 3 bits of flags matter
378 if (modifyTime != null) {
379 hc ^= modifyTime.hashCode();
380 }
381 if (accessTime != null) {
382 // Since accessTime is often same as modifyTime,
383 // this prevents them from XOR negating each other.
384 hc ^= Integer.rotateLeft(accessTime.hashCode(), 11);
385 }
386 if (createTime != null) {
387 hc ^= Integer.rotateLeft(createTime.hashCode(), 22);
388 }
389 return hc;
390 }
391
392 /**
393 * 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
394 * entry.
395 *
396 * @return true if bit0 of the flags byte is set.
397 */
398 public boolean isBit0_modifyTimePresent() {
399 return bit0_modifyTimePresent;
400 }
401
402 /**
403 * 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
404 * ZIP entry.
405 *
406 * @return true if bit1 of the flags byte is set.
407 */
408 public boolean isBit1_accessTimePresent() {
409 return bit1_accessTimePresent;
410 }
411
412 /**
413 * 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
414 * entry.
415 *
416 * @return true if bit2 of the flags byte is set.
417 */
418 public boolean isBit2_createTimePresent() {
419 return bit2_createTimePresent;
420 }
421
422 /**
423 * Doesn't do anything special since this class always uses the same parsing logic for both central directory and local file data.
424 */
425 @Override
426 public void parseFromCentralDirectoryData(final byte[] buffer, final int offset, final int length) throws ZipException {
427 reset();
428 parseFromLocalFileData(buffer, offset, length);
429 }
430
431 /**
432 * Populate data from this array as if it was in local file data.
433 *
434 * @param data an array of bytes
435 * @param offset the start offset
436 * @param length the number of bytes in the array from offset
437 * @throws java.util.zip.ZipException on error
438 */
439 @Override
440 public void parseFromLocalFileData(final byte[] data, int offset, final int length) throws ZipException {
441 reset();
442 if (length < 1) {
443 throw new ZipException("X5455_ExtendedTimestamp too short, only " + length + " bytes");
444 }
445 final int len = offset + length;
446 setFlags(data[offset++]);
447 if (bit0_modifyTimePresent && offset + 4 <= len) {
448 modifyTime = new ZipLong(data, offset);
449 offset += 4;
450 } else {
451 bit0_modifyTimePresent = false;
452 }
453 if (bit1_accessTimePresent && offset + 4 <= len) {
454 accessTime = new ZipLong(data, offset);
455 offset += 4;
456 } else {
457 bit1_accessTimePresent = false;
458 }
459 if (bit2_createTimePresent && offset + 4 <= len) {
460 createTime = new ZipLong(data, offset);
461 offset += 4; // NOSONAR - assignment as documentation
462 } else {
463 bit2_createTimePresent = false;
464 }
465 }
466
467 /**
468 * Reset state back to newly constructed state. Helps us make sure parse() calls always generate clean results.
469 */
470 private void reset() {
471 setFlags((byte) 0);
472 this.modifyTime = null;
473 this.accessTime = null;
474 this.createTime = null;
475 }
476
477 /**
478 * <p>
479 * Sets the acccess time as a {@link FileTime} of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
480 * </p>
481 * <p>
482 * 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
483 * flags is also set.
484 * </p>
485 *
486 * @param time access time as {@link FileTime}
487 * @since 1.23
488 */
489 public void setAccessFileTime(final FileTime time) {
490 setAccessTime(fileTimeToZipLong(time));
491 }
492
493 /**
494 * <p>
495 * Sets the access time as a java.util.Date of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
496 * </p>
497 * <p>
498 * 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
499 * flags is also set.
500 * </p>
501 *
502 * @param d access time as java.util.Date
503 */
504 public void setAccessJavaTime(final Date d) {
505 setAccessTime(dateToZipLong(d));
506 }
507
508 /**
509 * <p>
510 * Sets the access time (seconds since epoch) of this ZIP entry using a ZipLong object
511 * </p>
512 * <p>
513 * 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
514 * flags is also set.
515 * </p>
516 *
517 * @param l ZipLong of the access time (seconds per epoch)
518 */
519 public void setAccessTime(final ZipLong l) {
520 bit1_accessTimePresent = l != null;
521 flags = (byte) (l != null ? flags | ACCESS_TIME_BIT : flags & ~ACCESS_TIME_BIT);
522 this.accessTime = l;
523 }
524
525 /**
526 * <p>
527 * Sets the create time as a {@link FileTime} of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
528 * </p>
529 * <p>
530 * 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
531 * flags is also set.
532 * </p>
533 *
534 * @param time create time as {@link FileTime}
535 * @since 1.23
536 */
537 public void setCreateFileTime(final FileTime time) {
538 setCreateTime(fileTimeToZipLong(time));
539 }
540
541 /**
542 * <p>
543 * Sets the create time as a java.util.Date of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
544 * </p>
545 * <p>
546 * 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
547 * flags is also set.
548 * </p>
549 *
550 * @param d create time as java.util.Date
551 */
552 public void setCreateJavaTime(final Date d) {
553 setCreateTime(dateToZipLong(d));
554 }
555
556 /**
557 * <p>
558 * Sets the create time (seconds since epoch) of this ZIP entry using a ZipLong object
559 * </p>
560 * <p>
561 * 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
562 * flags is also set.
563 * </p>
564 *
565 * @param l ZipLong of the create time (seconds per epoch)
566 */
567 public void setCreateTime(final ZipLong l) {
568 bit2_createTimePresent = l != null;
569 flags = (byte) (l != null ? flags | CREATE_TIME_BIT : flags & ~CREATE_TIME_BIT);
570 this.createTime = l;
571 }
572
573 /**
574 * Sets flags byte. The flags byte tells us which of the three datestamp fields are present in the data:
575 *
576 * <pre>
577 * bit0 - modify time
578 * bit1 - access time
579 * bit2 - create time
580 * </pre>
581 *
582 * Only first 3 bits of flags are used according to the latest version of the spec (December 2012).
583 *
584 * @param flags flags byte indicating which of the three datestamp fields are present.
585 */
586 public void setFlags(final byte flags) {
587 this.flags = flags;
588 this.bit0_modifyTimePresent = (flags & MODIFY_TIME_BIT) == MODIFY_TIME_BIT;
589 this.bit1_accessTimePresent = (flags & ACCESS_TIME_BIT) == ACCESS_TIME_BIT;
590 this.bit2_createTimePresent = (flags & CREATE_TIME_BIT) == CREATE_TIME_BIT;
591 }
592
593 /**
594 * <p>
595 * Sets the modify time as a {@link FileTime} of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
596 * </p>
597 * <p>
598 * 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
599 * flags is also set.
600 * </p>
601 *
602 * @param time modify time as {@link FileTime}
603 * @since 1.23
604 */
605 public void setModifyFileTime(final FileTime time) {
606 setModifyTime(fileTimeToZipLong(time));
607 }
608
609 /**
610 * <p>
611 * Sets the modify time as a java.util.Date of this ZIP entry. Supplied value is truncated to per-second precision (milliseconds zeroed-out).
612 * </p>
613 * <p>
614 * 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
615 * flags is also set.
616 * </p>
617 *
618 * @param d modify time as java.util.Date
619 */
620 public void setModifyJavaTime(final Date d) {
621 setModifyTime(dateToZipLong(d));
622 }
623
624 /**
625 * <p>
626 * Sets the modify time (seconds since epoch) of this ZIP entry using a ZipLong object.
627 * </p>
628 * <p>
629 * 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
630 * flags is also set.
631 * </p>
632 *
633 * @param l ZipLong of the modify time (seconds per epoch)
634 */
635 public void setModifyTime(final ZipLong l) {
636 bit0_modifyTimePresent = l != null;
637 flags = (byte) (l != null ? flags | MODIFY_TIME_BIT : flags & ~MODIFY_TIME_BIT);
638 this.modifyTime = l;
639 }
640
641 /**
642 * Returns a String representation of this class useful for debugging purposes.
643 *
644 * @return A String representation of this class useful for debugging purposes.
645 */
646 @Override
647 public String toString() {
648 final StringBuilder buf = new StringBuilder();
649 buf.append("0x5455 Zip Extra Field: Flags=");
650 buf.append(Integer.toBinaryString(ZipUtil.unsignedIntToSignedByte(flags))).append(" ");
651 if (bit0_modifyTimePresent && modifyTime != null) {
652 final Date m = getModifyJavaTime();
653 buf.append(" Modify:[").append(m).append("] ");
654 }
655 if (bit1_accessTimePresent && accessTime != null) {
656 final Date a = getAccessJavaTime();
657 buf.append(" Access:[").append(a).append("] ");
658 }
659 if (bit2_createTimePresent && createTime != null) {
660 final Date c = getCreateJavaTime();
661 buf.append(" Create:[").append(c).append("] ");
662 }
663 return buf.toString();
664 }
665
666 }